Cisco 5505 - ASA Firewall Edition Bundle, 5520 - ASA IPS Edition Bundle, ASA 5540, ASA 5550 Series, ASA 5580, ASA 5510 Configuration Manual

Cisco ASA 5500 Series Configuration

Guide using ASDM

Software Version 6.3, for use with Cisco ASA 5500 Version 8.3

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Text Part Number: OL-20339-01

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Cisco ASA 5500 Series Configuration Guide using ASDM

Copyright © 2010 Cisco Systems, Inc. All rights reserved.

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C O N T E N T S

About This Guide lix

Document Objectives

lix

Audience

lix

Related Documentation

lx

Document Conventions

lx

Obtaining Documentation, Obtaining Support, and Security Guidelines

lx

Getting Started and General Information

Introduction to the Cisco ASA 5500 Series Adaptive Security Appliance

1-1

ASDM Client Operating System and Browser Requirements

1-1

ASA 5500 Model Support

1-2

Module Support

1-2

VPN Specifications

1-3

New Features

1-3

New Features in Version 6.3(2)/8.3(2)

1-3

New Features in Version 6.3(1)/8.3(1)

1-6

Unsupported Commands

1-13

Ignored and View-Only Commands

1-13

Effects of Unsupported Commands

1-14

Discontinuous Subnet Masks Not Supported

1-14

Interactive User Commands Not Supported by the ASDM CLI Tool

1-14

Firewall Functional Overview

1-15

Security Policy Overview

1-15

Permitting or Denying Traffic with Access Rules

1-16

Applying NAT

1-16

Protecting from IP Fragments

1-16

Using AAA for Through Traffic

1-16

Applying HTTP, HTTPS, or FTP Filtering

1-16

Applying Application Inspection

1-16

Sending Traffic to the Advanced Inspection and Prevention Security Services Module

1-16

Sending Traffic to the Content Security and Control Security Services Module

1-17

Applying QoS Policies

1-17

Applying Connection Limits and TCP Normalization

1-17

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C H A P T E R

2

C H A P T E R

3

Enabling Threat Detection

1-17

Enabling the Botnet Traffic Filter

1-17

Configuring Cisco Unified Communications

1-18

Firewall Mode Overview

1-18

Stateful Inspection Overview

1-18

VPN Functional Overview

1-19

Security Context Overview

1-20

Getting Started

2-1

Configuring the Security Appliance for ASDM Access

2-1

Starting ASDM

2-1

Downloading the ASDM Launcher

2-2

Starting ASDM from the ASDM Launcher

2-2

Using ASDM in Demo Mode

2-3

Starting ASDM from a Web Browser

2-4

Multiple ASDM Session Support

2-5

Factory Default Configurations

2-5

Restoring the Factory Default Configuration

2-5

ASA 5505 Default Configuration

2-6

ASA 5510 and Higher Default Configuration

2-7

Getting Started With the Configuration

2-8

Using the Command Line Interface

2-8

Using the Command Line Interface Tool

2-9

Handling Command Errors

2-9

Using Interactive Commands

2-9

Avoiding Conflicts with Other Administrators

2-10

Showing Commands Ignored by ASDM on the Device

2-10

Using the ASDM User Interface

3-1

Information About the ASDM User Interface

3-1

Navigating in the ASDM User Interface

3-3

Menus

3-4

File

Menu

3-4

View Menu

3-5

Tools Menu

3-6

Wizards Menu

3-8

Window Menu

3-9

Help Menu

3-9

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Toolbar

3-10

ASDM Assistant

3-10

Status Bar

3-11

Connection to Device

3-11

Device List

3-11

Common Buttons

3-12

Keyboard Shortcuts

3-13

Enabling Extended Screen Reader Support

3-14

Organizational Folder

3-15

About the Help Window

3-15

Header Buttons

3-15

Browser Window

3-15

Home Pane (Single Mode and Context)

3-16

Device Dashboard Tab

3-16

Device Information Pane

3-17

Interface Status Pane

3-17

VPN Sessions Pane

3-17

Failover Status Pane

3-18

System Resources Status Pane

3-18

Traffic Status Pane

3-18

Latest ASDM Syslog Messages Pane

3-18

Firewall Dashboard Tab

3-19

Traffic Overview Pane

3-20

Top 10 Access Rules Pane

3-20

Top Usage Status Pane

3-20

Top Ten Protected Servers Under SYN Attack Pane

3-21

Top 200 Hosts Pane

3-21

Top Botnet Traffic Filter Hits Pane

3-21

Content Security Tab

3-21

Intrusion Prevention Tab

3-22

Home Pane (System)

3-24

Managing Feature Licenses

4-1

Supported Feature Licenses Per Model

4-1

Licenses Per Model

4-2

License Notes

4-9

VPN License and Feature Compatibility

4-11

Information About Feature Licenses

4-11

Cisco ASA 5500 Series Configuration Guide using ASDM

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Contents

Preinstalled License

4-12

Permanent License

4-12

Time-Based Licenses

4-12

Time-Based License Activation Guidelines

4-12

How the Time-Based License Timer Works

4-12

How Permanent and Time-Based Licenses Combine

4-13

Stacking Time-Based Licenses

4-14

Time-Based License Expiration

4-14

Shared SSL VPN Licenses

4-14

Information About the Shared Licensing Server and Participants

4-15

Communication Issues Between Participant and Server

4-16

Information About the Shared Licensing Backup Server

4-16

Failover and Shared Licenses

4-17

Maximum Number of Participants

4-18

Failover Licenses

4-19

Failover License Requirements

4-19

How Failover Licenses Combine

4-19

Loss of Communication Between Failover Units

4-20

Upgrading Failover Pairs

4-20

Licenses FAQ

4-20

Guidelines and Limitations

4-21

Viewing Your Current License

4-23

Obtaining an Activation Key

4-23

Activating or Deactivating Keys

4-24

Configuring a Shared License

4-25

Configuring the Shared Licensing Server

4-25

Configuring the Shared Licensing Participant and the Optional Backup Server

4-26

Monitoring the Shared License

4-27

Feature History for Licensing

4-27

C H A P T E R

5

Configuring the Transparent or Routed Firewall

5-1

Configuring the Firewall Mode

5-1

Information About the Firewall Mode

5-1

Information About Routed Firewall Mode

5-2

Information About Transparent Firewall Mode

5-2

Licensing Requirements for the Firewall Mode

5-4

Default Settings

5-4


5-5

Setting the Firewall Mode

5-7

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Configuring ARP Inspection for the Transparent Firewall

5-8

Information About ARP Inspection

5-8

Licensing Requirements for ARP Inspection

5-8

Default Settings

5-9


5-9

Configuring ARP Inspection

5-9

Task Flow for Configuring ARP Inspection

5-9

Adding a Static ARP Entry

5-9

Enabling ARP Inspection

5-10

Feature History for ARP Inspection

5-11

Customizing the MAC Address Table for the Transparent Firewall

5-11

Information About the MAC Address Table

5-11

Licensing Requirements for the MAC Address Table

5-12

Default Settings

5-12


5-12

Configuring the MAC Address Table

5-13

Adding a Static MAC Address

5-13

Disabling MAC Address Learning

5-13

Feature History for the MAC Address Table

5-14

Firewall Mode Examples

5-14

How Data Moves Through the Security Appliance in Routed Firewall Mode

5-14

An Inside User Visits a Web Server

5-15

An Outside User Visits a Web Server on the DMZ

5-16

An Inside User Visits a Web Server on the DMZ

5-17

An Outside User Attempts to Access an Inside Host

5-18

A DMZ User Attempts to Access an Inside Host

5-19

How Data Moves Through the Transparent Firewall

5-20

An Inside User Visits a Web Server

5-21

An Inside User Visits a Web Server Using NAT

5-22

An Outside User Visits a Web Server on the Inside Network

5-23

An Outside User Attempts to Access an Inside Host

5-24

Setting up the Adaptive Security Appliance

Configuring Multiple Context Mode

6-1

Information About Security Contexts

6-1

Common Uses for Security Contexts

6-2

Context Configuration Files

6-2

Context Configurations

6-2


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Contents

System Configuration

6-2

Admin Context Configuration

6-2

How the Security Appliance Classifies Packets

6-3

Valid Classifier Criteria

6-3

Classification Examples

6-4

Cascading Security Contexts

6-6

Management Access to Security Contexts

6-7

System Administrator Access

6-7

Context Administrator Access

6-8

Information About Resource Management

6-8

Resource Limits

6-8

Default Class

6-9

Class Members

6-10

Information About MAC Addresses

6-11

Default MAC Address

6-11

Interaction with Manual MAC Addresses

6-11

Failover MAC Addresses

6-11

MAC Address Format

6-11

Licensing Requirements for Multiple Context Mode

6-12


6-12

Default Settings

6-13

Configuring Multiple Contexts

6-13

Task Flow for Configuring Multiple Context Mode

6-13

Enabling or Disabling Multiple Context Mode

6-14

Enabling Multiple Context Mode

6-14

Restoring Single Context Mode

6-14

Configuring a Class for Resource Management

6-15

Configuring a Security Context

6-17

Automatically Assigning MAC Addresses to Context Interfaces

6-19

Monitoring Security Contexts

6-20

Monitoring Context Resource Usage

6-20

Viewing Assigned MAC Addresses

6-21

Viewing MAC Addresses in the System Configuration

6-21

Viewing MAC Addresses Within a Context

6-22

Feature History for Multiple Context Mode

6-23

C H A P T E R

7

Using the Startup Wizard

7-1

Information About the Startup Wizard

7-1

Licensing Requirements for the Startup Wizard

7-1

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Prerequisites for the Startup Wizard

7-2


7-2

Startup Wizard Screens for ASA 5500 Series Adaptive Security Appliances

7-3

Startup Wizard Screens for the ASA 5505 Adaptive Security Appliance

7-3

Step 1 - Starting Point or Welcome

7-4

Step 2 - Basic Configuration

7-5

Step 3 - Time Zone and Clock Configuration

7-5

Step 4 - Auto Update Server

7-6

Step 5 - Management IP Address Configuration

7-6

Step 6 - Interface Selection

7-6

Step 7 - Switch Port Allocation

7-7

Step 8 - Interface IP Address Configuration

7-8

Step 9 - Internet Interface Configuration - PPPoE

7-8

Step 10 - Business Interface Configuration - PPPoE

7-9

Step 11 - Home Interface Configuration - PPPoE

7-10

Step 12 - General Interface Configuration

7-10

Step 13 - Static Routes

7-11

Adding or Editing Static Routes

7-11

Step 14 - DHCP Server

7-11

Step 15 - Address Translation (NAT/PAT)

7-12

Step 16 - Administrative Access

7-13

Adding or Editing Administrative Access Entry

7-13

Step 17 - Easy VPN Remote Configuration

7-14

Step 18 - Startup Wizard Summary

7-16

Other Interfaces Configuration

7-16

Editing Interfaces

7-16

Configuring IPv6 Neighbor Discovery

7-18

Configuring Neighbor Solicitation Messages

7-18

Configuring the Neighbor Solicitation Message Interval

7-19

Configuring the Neighbor Reachable Time

7-19

Configuring DAD Settings

7-20

Configuring IPv6 Addresses on an Interface

7-21

Configuring IPv6 Prefixes on an Interface

7-21

Configuring Router Advertisement Messages

7-22

Configuring the Router Advertisement Transmission Interval

7-23

Configuring the Router Lifetime Value

7-24

Suppressing Router Advertisement Messages

7-25

Configuring IPv6 Static Neighbors

7-25

Adding an IPv6 Static Neighbor

7-25


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Contents

Editing Static Neighbors

7-26

Deleting Static Neighbors

7-26

Viewing and Clearing Dynamic Neighbors

7-27

Interface Configuration

7-27

Outside Interface Configuration - PPPoE

7-27

Outside Interface Configuration

7-28

Feature History for the Startup Wizard

7-29

C H A P T E R

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x

Configuring Interfaces

8-1

Information About Interfaces

8-1

ASA 5505 Interfaces

8-2

Understanding ASA 5505 Ports and Interfaces

8-2

Maximum Active VLAN Interfaces for Your License

8-2

VLAN MAC Addresses

8-4

Power over Ethernet

8-4

Monitoring Traffic Using SPAN

8-4

ASA 5580 Interfaces

8-5

Auto-MDI/MDIX Feature

8-5

Security Levels

8-5

Dual IP Stack

8-6

Management Interface (ASA 5510 and Higher)

8-6

Licensing Requirements for Interfaces

8-6


8-7

Default Settings

8-8

Starting Interface Configuration (ASA 5510 and Higher)

8-9

Task Flow for Starting Interface Configuration

8-9

Enabling the Physical Interface and Configuring Ethernet Parameters

8-10

Configuring a Redundant Interface

8-12

Configuring a Redundant Interface

8-12

Changing the Active Interface

8-14

Configuring VLAN Subinterfaces and 802.1Q Trunking

8-14

Assigning Interfaces to Contexts and Automatically Assigning MAC Addresses (Multiple Context

Mode)

8-16

Starting Interface Configuration (ASA 5505)

8-16

Task Flow for Starting Interface Configuration

8-16

Configuring VLAN Interfaces

8-17

Configuring and Enabling Switch Ports as Access Ports

8-18

Configuring and Enabling Switch Ports as Trunk Ports

8-19

Completing Interface Configuration (All Models)

8-21


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Task Flow for Completing Interface Configuration

8-21

Configuring General Interface Parameters

8-22

PPPoE IP Address and Route Settings

8-25

Configuring Advanced Interface Parameters

8-26

Configuring IPv6 Addressing

8-27

Configuring the Link-Local Address on an Interface (Transparent Firewall Mode)

8-30

Allowing Same Security Level Communication

8-31

Enabling Jumbo Frame Support (ASA 5580, Multiple Mode)

8-32

Monitoring Interfaces

8-32

ARP Table

8-33

DHCP

8-33

DHCP Server Table

8-33

DHCP Client Lease Information

8-33

DHCP Statistics

8-35

MAC Address Table

8-35

Dynamic ACLs

8-36

Interface Graphs

8-36

Graph/Table

8-38

PPPoE Client

8-39

Interface

Connection

8-39

Track Status for

8-39

Monitoring Statistics for

8-39

Feature History for Interfaces

8-40

Configuring Basic Settings

9-1

Configuring the Hostname, Domain Name, and Passwords

9-1

Setting the Date and Time

9-2

Setting the Date and Time Using an NTP Server

9-3

Add/Edit NTP Server Configuration

9-3

Setting the Date and Time Manually

9-5

Configuring HTTP Redirect

9-5

Edit HTTP/HTTPS Settings

9-6

Configuring the Master Passphrase

9-6

Information About the Master Passphrase

9-6

Licensing Requirements for the Master Passphrase

9-7


9-7

Adding or Changing the Master Passphrase

9-7

Disabling the Master Passphrase

9-8

Recovering the Master Passphrase

9-9

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C H A P T E R

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Feature History for the Master Passphrase

9-9

Configuring the DNS Server

9-10

Defining ASDM Preferences

9-11

Using the ASDM Assistant

9-13

Enabling History Metrics

9-13

Setting the Management IP Address for a Transparent Firewall

9-14

Information About the Management IP Address

9-14

Licensing Requirements for the Management IP Address for a Transparent Firewall

9-14


9-14

Configuring the IPv4 Address

9-15

Configuring the IPv6 Address

9-16

Configuring the Global Address

9-16

Configuring the Link-Local Addresses Automatically

9-17


9-17

Feature History for the Management IP Address for a Transparent Firewall

9-18

Configuring DHCP

10-1

Information About DHCP

10-1

Licensing Requirements for DHCP

10-1


10-2

Configuring DHCP Relay Services

10-2

Editing DHCP Relay Agent Settings

10-4

Adding or Editing Global DHCP Relay Server Settings

10-4

Configuring a DHCP Server

10-5

Editing DHCP Servers

10-6

Configuring Advanced DHCP Options

10-7

DHCP Monitoring

10-8

Feature History for DHCP

10-9

Configuring Dynamic DNS

11-1

Information about DDNS

11-1

Licensing Requirements for DDNS

11-1


11-2

Configuring Dynamic DNS

11-2

DDNS Monitoring

11-4

Feature History for DDNS

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Configuring Web Cache Services Using WCCP

12-1

Information About WCCP

12-1


12-1

Licensing Requirements for WCCP

12-2

Configuring WCCP Service Groups

12-3

Adding or Editing WCCP Service Groups

12-3

Configuring Packet Redirection

12-4

Adding or Editing Packet Redirection

12-4

WCCP Monitoring

12-4

Feature History for WCCP

12-5

Configuring Objects

13-1

Configuring Network Objects and Groups

13-1

Network Object Overview

13-2

Configuring a Network Object

13-2

Configuring a Network Object Group

13-3

Using Network Objects and Groups in a Rule

13-4

Viewing the Usage of a Network Object or Group

13-4

Configuring Service Objects and Service Groups

13-5

Information about Service Objects and Service Groups

13-5

Adding and Editing a Service Object

13-6

Adding a Service Object

13-6

Editing a Service Object

13-6

Adding and Editing a Service Group

13-7

Adding a Service Group

13-7

Editing a Service Group

13-8

Browse Service Groups

13-9

Licensing Requirements for Objects and Groups

13-9

Guidelines and Limitations for Objects and Groups

13-10

Configuring Regular Expressions

13-10

Creating a Regular Expression

13-10

Building a Regular Expression

13-13

Testing a Regular Expression

13-14

Creating a Regular Expression Class Map

13-15

Configuring Time Ranges

13-15

Add/Edit Time Range

13-16

Adding a Time Range to an Access Rule

13-16

Add/Edit Recurring Time Range

13-18


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Contents

C H A P T E R

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C H A P T E R

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C H A P T E R

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C H A P T E R

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Configuring Public Servers

14-1

Public Server Overview

14-1

Adding a Public Server

14-2

Adding a Public Server that Enables Static NAT

14-2

Adding a Public Server that Enables Static NAT with Port Address Translation

14-2

Editing a Public Server

14-3

Configuring ACLs

Using the ACL Manager

15-1

Standard ACL

15-1

Extended ACL

15-2

Add/Edit/Paste ACE

15-3

Adding a WebtypeACL

16-1

Licensing Requirements for Webtype ACLs

16-1


16-1

Default Settings

16-2

Using Webtype ACLs

16-2

Task Flow for Configuring Webtype ACLs

16-2

Adding a Webtype ACL and ACE

16-2

Editing Webtype ACLs and ACEs

16-4

Deleting Webtype ACLs and ACEs

16-5

Feature History for Webtype Access Lists

16-5

Adding a StandardACL

17-1

Information About Standard ACLs

17-1

Licensing Requirements for Standard ACLs

17-1


17-1

Default Settings

17-2

Adding Standard ACLs

17-2

Using Standard ACLs

17-3

Adding a Standard ACL

17-3

Adding an ACE to a Standard ACL

17-3

Editing an ACE in a Standard ACL

17-4

Feature History for Standard ACLs

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Configuring IP Routing

Information About Routing

18-1

Information About Routing

18-1

Switching

18-1

Path Determination

18-2

Supported Route Types

18-2

Static Versus Dynamic

18-2

Single-Path Versus Multipath

18-3

Flat Versus Hierarchical

18-3

Link-State Versus Distance Vector

18-3

How Routing Behaves Within the Adaptive Security Appliance

18-4

Egress Interface Selection Process

18-4

Next Hop Selection Process

18-4

Supported Internet Protocols for Routing

18-5

Information About the Routing Table

18-5

Displaying the Routing Table

18-5

How the Routing Table Is Populated

18-6

Backup Routes

18-7

How Forwarding Decisions are Made

18-7

Dynamic Routing and Failover

18-8

Information About IPv6 Support

18-8

Features that Support IPv6

18-9

IPv6-Enabled Commands

18-9

IPv6 Command Guidelines in Transparent Firewall Mode

18-10

Entering IPv6 Addresses in Commands

18-10

Disabling Proxy ARPs

18-11

Configuring Static and Default Routes

19-1

Information About Static and Default Routes

19-1

Licensing Requirements for Static and Default Routes

19-2


19-2

Configuring Static and Default Routes

19-2

Configuring a Static Route

19-3

Add/Edit a Static Route

19-3

Configuring Static Route Tracking

19-6

Deleting Static Routes

19-6

Configuring a Default Static Route

19-7


Contents xv

Contents

Limitations on Configuring a Default Static Route

19-7

Configuring IPv6 Default and Static Routes

19-8

Monitoring a Static or Default Route

19-8

Configuration Examples for Static or Default Routes

19-9

Feature History for Static and Default Routes

19-9

C H A P T E R

20

Defining Route Maps

20-1

Route Maps Overview

20-1

Permit and Deny Clauses

20-2

Match and Set Clause Values

20-2

Licensing Requirements for Route Maps

20-3


20-3

Defining a Route Map

20-4

Add/Edit a Route Map

20-4

Customizing a Route Map

20-5

Defining a Route to Match a Specific Destination Address

20-5

Configuring the Metric Values for a Route Action

20-6

Configuration Example for Route Maps

20-7

Feature History for Route Maps

20-7

C H A P T E R

21

Configuring OSPF

21-1

Information About OSPF

21-1

Licensing Requirements for OSPF

21-3


21-3

Configuring OSPF

21-3

Customizing OSPF

21-4

Redistributing Routes Into OSPF

21-5

Configuring Route Summarization When Redistributing Routes into OSPF

21-7

Add a Route Summary Address

21-7

Add/Edit OSPF Summary Address

21-8

Configuring Route Summarization Between OSPF Areas

21-8

Configuring OSPF Interface Parameters

21-9

Configuring OSPF Area Parameters

21-12

Configuring OSPF NSSA

21-13

Defining Static OSPF Neighbors

21-14

Configuring Route Calculation Timers

21-15

Logging Neighbors Going Up or Down

21-16

Configuring Filtering in OSPF

21-16

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Configuring a Virtual Link in OSPF

21-17

Restarting the OSPF Process

21-19

Configuration Example for OSPF

21-19

Monitoring OSPF

21-20

Feature History for OSPF

21-21

Configuring RIP

22-1

Overview

22-1

Routing Update Process

22-2

RIP Routing Metric

22-2

RIP Stability Features

22-2

RIP Timers

22-2

Licensing Requirements for RIP

22-2


22-3

Configuring RIP

22-3

Enabling RIP

22-4

Customizing RIP

22-5

Configure the RIP Version

22-5

Configuring Interfaces for RIP

22-6

Editing a RIP Interface

22-6

Configuring the RIP Send and Receive Version on an Interface

22-7

Configuring Route Summarization

22-8

Filtering Networks in RIP

22-9

Adding or Editing a Filter Rule

22-10

Redistributing Routes into the RIP Routing Process

22-10

Enabling RIP Authentication

22-11

Restarting the RIP Process

22-12

Monitoring RIP

22-12

Configuration Example for RIP

22-13

Feature History for RIP

22-13

Configuring EIGRP

23-1

Overview

23-1

Licensing Requirements for EIGRP

23-2


23-2

Task List to Configure an EIGRP Process

23-3

Configuring EIGRP

23-3


Contents xvii

Contents

Enabling EIGRP

23-4

Enabling EIGRP Stub Routing

23-5

Customizing EIGRP

23-6

Defining a Network for an EIGRP Routing Process

23-7

Configuring Interfaces for EIGRP

23-7

Configuring Passive Interfaces

23-8

Configuring the Summary Aggregate Addresses on Interfaces

23-9

Changing the Interface Delay Value

23-10

Enabling EIGRP Authentication on an Interface

23-10

Defining an EIGRP Neighbor

23-11

Redistributing Routes Into EIGRP

23-12

Filtering Networks in EIGRP

23-13

Customizing the EIGRP Hello Interval and Hold Time

23-15

Disabling Automatic Route Summarization

23-15

Configuring Default Information in EIGRP

23-16

Disabling EIGRP Split Horizon

23-17

Restarting the EIGRP Process

23-18

Monitoring EIGRP

23-18

Configuration Example for EIGRP

23-18

Feature History for EIGRP

23-20

C H A P T E R

24

Configuring Multicast Routing

24-1

Information About Multicast Routing

24-1

Stub Multicast Routing

24-2

PIM Multicast Routing

24-2

Multicast Group Concept

24-2

Multicast Addresses

24-2

Licensing Requirements for Multicast Routing

24-2


24-3

Enabling Multicast Routing

24-3

Customizing Multicast Routing

24-4

Configuring Stub Multicast Routing

24-4

Configuring a Static Multicast Route

24-4

Configuring IGMP Features

24-5

Disabling IGMP on an Interface

24-6

Configuring IGMP Group Membership

24-6

Configuring a Statically Joined IGMP Group

24-7

Controlling Access to Multicast Groups

24-8

Limiting the Number of IGMP States on an Interface

24-8

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Modifying the Query Messages to Multicast Groups

24-9

Changing the IGMP Version

24-9

Configuring PIM Features

24-10

Enabling and Disabling PIM on an Interface

24-10

Configuring a Static Rendezvous Point Address

24-11

Configuring the Designated Router Priority

24-12

Configuring and Filtering PIM Register Messages

24-12

Configuring PIM Message Intervals

24-13

Configuring a Route Tree

24-13

Configuring a Multicast Group

24-14

Filtering PIM Neighbors

24-14

Configuring a Bidirectional Neighbor Filter

24-15

Configuring a Multicast Boundary

24-16

Configuration Example for Multicast Routing

24-17

Additional References

24-18

Related Documents

24-19

RFCs

24-19

Feature History for Multicast Routing

24-19

Configuring IPv6 Neighbor Discovery

25-1

Configuring Neighbor Solicitation Messages

25-1


25-1

Information About Neighbor Solicitation Messages

25-2

Licensing Requirements for Neighbor Solicitation Messages

25-2

Guidelines and Limitations for the Neighbor Solicitation Message Interval

25-3

Default Settings for the Neighbor Solicitation Message Interval

25-3


25-3

Feature History for the Neighbor Solicitation Message Interval

25-4

Configuring the Neighbor Reachable Time

25-4

Information About Neighbor Reachable Time

25-4

Licensing Requirements for Neighbor Reachable Time

25-4

Guidelines and Limitations for Neighbor Reachable Time

25-4

Default Settings for the Neighbor Reachable Time

25-5

Configuring Neighbor Reachable Time

25-5


25-5

Configuring IPv6 Addresses on an Interface

25-6

Configuring IPv6 Prefixes on an Interface

25-7

Feature History for Neighbor Reachable Time

25-8

Configuring Router Advertisement Messages

25-8


Contents xix

Contents

P A R T

5

C H A P T E R

26

Information About Router Advertisement Messages

25-8

Configuring the Router Advertisement Transmission Interval

25-10

Licensing Requirements for Router Advertisement Transmission Interval

25-10

Guidelines and Limitations for the Router Advertisement Transmission Interval

25-10

Default Settings for Router Advertisement Transmission Interval

25-10

Configuring Router Advertisement Transmission Interval

25-11

Feature History for the Router Advertisement Transmission Interval

25-11


25-12

Licensing Requirements for the Router Lifetime Value

25-12

Guidelines and Limitations for the Router Lifetime Value

25-12

Default Settings for the Router Lifetime Value

25-12


25-13

Feature History for the Router Lifetime Value

25-13

Configuring the IPv6 Prefix

25-14

Licensing Requirements for IPv6 Prefixes

25-14

Guidelines and Limitations for IPv6 Prefixes

25-14

Default Settings for IPv6 Prefixes

25-15

Configuring IPv6 Prefixes

25-15


25-16

Licensing Requirements for Suppressing Router Advertisement Messages

25-16

Guidelines and Limitations for Suppressing Router Advertisement Messages

25-16

Default Settings for Suppressing Router Advertisement Messages

25-17


25-17

Feature History for Suppressing Router Advertisement Messages

25-17

Configuring a Static IPv6 Neighbor

25-18

Information About a Static IPv6 Neighbor

25-18

Licensing Requirements for Static IPv6 Neighbor

25-18


25-18

Default Settings

25-18

Configuring a Static IPv6 Neighbor

25-19

Editing Static Neighbors

25-19

Deleting Static Neighbors

25-19

Feature History for Configuring a Static IPv6 Neighbor

25-20

Configuring Network Address Translation

Information About NAT

26-1

Why Use NAT?

26-1

NAT Terminology

26-2

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NAT Types

26-2

Static NAT

26-3

Information About Static NAT

26-3

Information About Static NAT with Port Translation

26-3

Information About One-to-Many Static NAT

26-6

Information About Other Mapping Scenarios (Not Recommended)

26-7

Dynamic NAT

26-8

Information About Dynamic NAT

26-9

Dynamic NAT Disadvantages and Advantages

26-10

Dynamic PAT

26-10

Information About Dynamic PAT

26-10

Dynamic PAT Disadvantages and Advantages

26-11

Identity NAT

26-11

NAT in Routed and Transparent Mode

26-12

NAT in Routed Mode

26-13

NAT in Transparent Mode

26-13

How NAT is Implemented

26-15

Main Differences Between Network Object NAT and Twice NAT

26-15

Information About Network Object NAT

26-16

Information About Twice NAT

26-16

NAT Rule Order

26-19

NAT Interfaces

26-20

Mapped Address Guidelines

26-20

DNS and NAT

26-21

Where to Go Next

26-23

Configuring Network Object NAT

27-1

Information About Network Object NAT

27-1

Licensing Requirements for Network Object NAT

27-2

Prerequisites for Network Object NAT

27-2


27-2

Configuring Network Object NAT

27-3

Configuring Dynamic NAT

27-3

Configuring Dynamic PAT (Hide)

27-7

Configuring Static NAT or Static NAT with Port Translation

27-11

Configuring Identity NAT

27-14

Configuration Examples for Network Object NAT

27-17

Providing Access to an Inside Web Server (Static NAT)

27-18


Contents xxi

Contents

C H A P T E R

28

P A R T

6

C H A P T E R

29

NAT for Inside Hosts (Dynamic NAT) and NAT for an Outside Web Server (Static NAT)

27-20

Inside Load Balancer with Multiple Mapped Addresses (Static NAT, One-to-Many)

27-25

Single Address for FTP, HTTP, and SMTP (Static NAT with Port Translation)

27-29

DNS Server on Mapped Interface, Web Server on Real Interface (Static NAT with DNS

Modification)

27-32

DNS Server and Web Server on Mapped Interface, Web Server is Translated (Static NAT with DNS

Modification)

27-35

Feature History for Network Object NAT

27-37

Configuring Twice NAT

28-1

Information About Twice NAT

28-1

Licensing Requirements for Twice NAT

28-1

Prerequisites for Twice NAT

28-2


28-2

Configuring Twice NAT

28-3

Configuring Dynamic NAT

28-3

Configuring Dynamic PAT (Hide)

28-7

Configuring Static NAT or Static NAT with Port Translation

28-11

Configuring Identity NAT

28-15

Configuration Examples for Twice NAT

28-18

Different Translation Depending on the Destination (Dynamic PAT)

28-19

Different Translation Depending on the Destination Address and Port (Dynamic PAT)

28-28

Feature History for Twice NAT

28-37

Configuring Service Policies

Configuring a Service Policy

29-1

Information About Service Policies

29-1

Supported Features for Through Traffic

29-1

Supported Features for Management Traffic

29-2

Feature Directionality

29-2

Feature Matching Within a Service Policy

29-3

Order in Which Multiple Feature Actions are Applied

29-4

Incompatibility of Certain Feature Actions

29-5

Feature Matching for Multiple Service Policies

29-5

Licensing Requirements for Service Policies

29-6


29-6

Default Settings

29-7

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Default Configuration

29-7

Default Traffic Classes

29-8

Task Flows for Configuring Service Policies

29-8

Task Flow for Configuring a Service Policy Rule

29-8

Adding a Service Policy Rule for Through Traffic

29-8

Adding a Service Policy Rule for Management Traffic

29-12

Configuring a Service Policy Rule for Management Traffic

29-12

Managing the Order of Service Policy Rules

29-15

Feature History for Service Policies

29-16

Configuring Access Control

Configuring Access Rules

30-1

Information About Access Rules

30-1

General Information About Rules

30-2

Implicit Permits

30-2

Using Access Rules and EtherType Rules on the Same Interface

30-2

Rule Order

30-2

Implicit Deny

30-3

Inbound and Outbound Rules

30-3

Using Global Access Rules

30-4

Information About Access Rules

30-4

Access Rules for Returning Traffic

30-5

Allowing Broadcast and Multicast Traffic through the Transparent Firewall Using Access

Rules

30-5

Management Access Rules

30-5

Information About EtherType Rules

30-5

Supported EtherTypes

30-6

Access Rules for Returning Traffic

30-6

Allowing MPLS

30-6

Licensing Requirements for Access Rules

30-6


30-7

Default Settings

30-7

Configuring Access Rules

30-7

Adding an Access Rule

30-7

Adding an EtherType Rule (Transparent Mode Only)

30-8

Add/Edit EtherType Rule

30-10

Configuring Management Access Rules

30-10

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31

Advanced Access Rule Configuration

30-11

Access Rule Explosion

30-12

Feature History for Access Rules

30-13

Configuring AAA Servers and the Local Database

31-1

AAA Overview

31-1

About Authentication

31-2

About Authorization

31-2

About Accounting

31-3

AAA Server and Local Database Support

31-3

Summary of Support

31-3

RADIUS Server Support

31-4

Authentication Methods

31-4

Attribute Support

31-5

RADIUS Authorization Functions

31-5

TACACS+ Server Support

31-5

RSA/SDI Server Support

31-5

RSA/SDI Version Support

31-6

Two-step Authentication Process

31-6

RSA/SDI Primary and Replica Servers

31-6

NT Server Support

31-6

Kerberos Server Support

31-6

LDAP Server Support

31-7

HTTP Forms Authentication for Clientless SSL VPN

31-7

Local Database Support

31-7

User Profiles

31-7

Fallback Support

31-7

Configuring AAA Server Groups

31-8

How Fallback Works with Multiple Servers in a Group

31-8

Adding a Server Group

31-8

Adding a Server to a Group

31-10

AAA Server Parameters

31-10

RADIUS Server Fields

31-11

TACACS+ Server Fields

31-12

SDI Server Fields

31-13

Windows NT Domain Server Fields

31-13

Kerberos Server Fields

31-13

LDAP Server Fields

31-15

HTTP Form Server Fields

31-17

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Testing Server Authentication and Authorization

31-18

Adding a User Account

31-18

Configuring VPN Policy Attributes for a User

31-20

Configuring LDAP Attribute Maps

31-22

Adding an Authentication Prompt

31-23

AAA Servers Monitoring

31-24


31-25

Related Documents

31-26

RFCs

31-26

Feature History for AAA Servers

31-26

Configuring Management Access

32-1

Configuring Device Access for ASDM, Telnet, or SSH

32-1

Configuring Management Access

32-1

Using an SSH Client

32-3

Configuring CLI Parameters

32-3

Configuring a Login Banner

32-3

Customizing a CLI Prompt

32-4

Changing the Console Timeout Period

32-5

Configuring File Access

32-5

Configuring the FTP Client Mode

32-6

Configuring the Adaptive Security Appliance as a Secure Copy Server

32-6

Configuring the Adaptive Security Appliance as a TFTP Client

32-6

Adding Mount Points

32-7

Adding a CIFS Mount Point

32-7

Adding an FTP Mount Point

32-8

Configuring ICMP Access

32-9

Configuring a Management Interface for Management on a Different Interface from the VPN Tunnel

Termination Interface

32-10

Configuring AAA for System Administrators

32-10

Configuring Authentication for CLI, ASDM, and enable command Access

32-11

Limiting User CLI and ASDM Access with Management Authorization

32-12

Configuring Command Authorization

32-13

Command Authorization Overview

32-13

Configuring Local Command Authorization

32-15

Configuring TACACS+ Command Authorization

32-18

Configuring Management Access Accounting

32-22

Viewing the Current Logged-In User

32-23

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Recovering from a Lockout

32-24

C H A P T E R

33

Configuring AAA Rules for Network Access

33-1

AAA Performance

33-1

Configuring Authentication for Network Access

33-1

Information About Authentication

33-2

One-Time Authentication

33-2

Applications Required to Receive an Authentication Challenge

33-2

Adaptive Security Appliance Authentication Prompts

33-2

Static PAT and HTTP

33-3

Configuring Network Access Authentication

33-4

Enabling the Redirection Method of Authentication for HTTP and HTTPS

33-5

Enabling Secure Authentication of Web Clients

33-5

Authenticating Directly with the Adaptive Security Appliance

33-6

Authenticating Telnet Connections with a Virtual Server

33-7

Authenticating HTTP(S) Connections with a Virtual Server

33-7

Configuring the Authentication Proxy Limit

33-9

Configuring Authorization for Network Access

33-9

Configuring TACACS+ Authorization

33-9

Configuring RADIUS Authorization

33-10

Configuring a RADIUS Server to Send Downloadable Access Control Lists

33-11

Configuring a RADIUS Server to Download Per-User Access Control List Names

33-15

Configuring Accounting for Network Access

33-15

Using MAC Addresses to Exempt Traffic from Authentication and Authorization

33-16

C H A P T E R

34

Configuring Filtering Services

34-1

Information About Web Traffic Filtering

34-1

Filtering URLs and FTP Requests with an External Server

34-2

Information About URL Filtering

34-2

Licensing Requirements for URL Filtering

34-3

Guidelines and Limitations for URL Filtering

34-3

Identifying the Filtering Server

34-3

Configuring Additional URL Filtering Settings

34-4

Buffering the Content Server Response

34-5

Caching Server Addresses

34-5

Filtering HTTP URLs

34-6

Configuring Filtering Rules

34-6

Filtering the Rule Table

34-11

Defining Queries

34-12

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Feature History for URL Filtering

34-12

Configuring Digital Certificates

35-1

Information About Digital Certificates

35-1

Public Key Cryptography

35-2

Certificate Scalability

35-3

Key Pairs

35-3

Trustpoints

35-4

Revocation Checking

35-4

CRLs

35-4

OCSP

35-5

The Local CA Server

35-6

Supported CA Servers

35-7

Certificate Enrollment

35-7

Storage for Local CA Files

35-8

Licensing Requirements for Digital Certificates

35-8


35-8

Configuring CA Certificate Authentication

35-9

Adding or Installing a CA Certificate

35-9

Editing or Removing a CA Certificate Configuration

35-10

Showing CA Certificate Details

35-11

Requesting a CRL

35-11

Configuring CA Certificates for Revocation

35-11

Configuring CRL Retrieval Policy

35-11

Configuring CRL Retrieval Methods

35-12

Configuring OCSP Rules

35-13

Configuring Advanced CRL and OCSP Settings

35-13

Configuring Identity Certificates Authentication

35-14

Adding or Importing an Identity Certificate

35-15

Showing Identity Certificate Details

35-17

Deleting an Identity Certificate

35-17

Exporting an Identity Certificate

35-17

Generating a Certificate Signing Request

35-18

Installing Identity Certificates

35-19

Configuring Code Signer Certificates

35-20

Showing Code Signer Certificate Details

35-20

Deleting a Code Signer Certificate

35-21

Importing a Code Signer Certificate

35-21

Exporting a Code Signer Certificate

35-21


Contents xxvii

Contents

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8

C H A P T E R

36

C H A P T E R

37

Authenticating Using the Local CA

35-22

Configuring the Local CA Server

35-22

Deleting the Local CA Server

35-25

Managing the User Database

35-25

Adding a Local CA User

35-26

Sending an Initial OTP or Replacing OTPs

35-26

Editing a Local CA User

35-26

Deleting a Local CA User

35-27

Allowing User Enrollment

35-27

Viewing or Regenerating an OTP

35-27

Managing User Certificates

35-28

Monitoring CRLs

35-28

Feature History for Certificate Management

35-29

Configuring Application Inspection

Getting Started With Application Layer Protocol Inspection

36-1

Information about Application Layer Protocol Inspection

36-1

How Inspection Engines Work

36-1

When to Use Application Protocol Inspection

36-2


36-3

Default Settings

36-3

Configuring Application Layer Protocol Inspection

36-5

Configuring Inspection of Basic Internet Protocols

37-1

DNS Inspection

37-1

How DNS Application Inspection Works

37-2

How DNS Rewrite Works

37-3

Configuring DNS Rewrite

37-3

Select DNS Inspect Map

37-5

DNS Class Map

37-6

Add/Edit DNS Traffic Class Map

37-6

Add/Edit DNS Match Criterion

37-7

DNS Inspect Map

37-8

Add/Edit DNS Policy Map (Security Level)

37-10

Add/Edit DNS Policy Map (Details)

37-11

FTP Inspection

37-13

FTP Inspection Overview

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Using Strict FTP

37-14

Select FTP Map

37-15

FTP Class Map

37-15

Add/Edit FTP Traffic Class Map

37-16

Add/Edit FTP Match Criterion

37-16

FTP Inspect Map

37-18

File Type Filtering

37-19

Add/Edit FTP Policy Map (Security Level)

37-20

Add/Edit FTP Policy Map (Details)

37-20

Add/Edit FTP Map

37-21

HTTP Inspection

37-23

HTTP Inspection Overview

37-24

Select HTTP Map

37-24

HTTP Class Map

37-25

Add/Edit HTTP Traffic Class Map

37-26

Add/Edit HTTP Match Criterion

37-26

HTTP Inspect Map

37-30

URI Filtering

37-31

Add/Edit HTTP Policy Map (Security Level)

37-32

Add/Edit HTTP Policy Map (Details)

37-33

Add/Edit HTTP Map

37-34

ICMP Inspection

37-38

ICMP Error Inspection

37-39

Instant Messaging Inspection

37-39

IM Inspection Overview

37-39

Select IM Map

37-39

IP Options Inspection

37-40

IP Options Inspection Overview

37-40

Configuring IP Options Inspection

37-41

Select IP Options Inspect Map

37-42

IP Options Inspect Map

37-43

Add/Edit IP Options Inspect Map

37-43

IPSec Pass Through Inspection

37-44

IPSec Pass Through Inspection Overview

37-44

Select IPSec-Pass-Thru Map

37-45

IPSec Pass Through Inspect Map

37-45

Add/Edit IPSec Pass Thru Policy Map (Security Level)

37-46

Add/Edit IPSec Pass Thru Policy Map (Details)

37-47

NetBIOS Inspection

37-48


Contents xxix

Contents

NetBIOS Inspection Overview

37-48

Select NETBIOS Map

37-48

NetBIOS Inspect Map

37-49

Add/Edit NetBIOS Policy Map

37-49

PPTP Inspection

37-50

SMTP and Extended SMTP Inspection

37-50

SMTP and ESMTP Inspection Overview

37-51

Select ESMTP Map

37-52

ESMTP Inspect Map

37-52

MIME File Type Filtering

37-54

Add/Edit ESMTP Policy Map (Security Level)

37-54

Add/Edit ESMTP Policy Map (Details)

37-56

Add/Edit ESMTP Inspect

37-57

TFTP Inspection

37-60

C H A P T E R

38

Configuring Inspection for Voice and Video Protocols

38-1

CTIQBE Inspection

38-1

CTIQBE Inspection Overview

38-1

Limitations and Restrictions

38-2

H.323 Inspection

38-2

H.323 Inspection Overview

38-3

How H.323 Works

38-3

H.239 Support in H.245 Messages

38-4

Limitations and Restrictions

38-4

Select H.323 Map

38-5

H.323 Class Map

38-5

Add/Edit H.323 Traffic Class Map

38-6

Add/Edit H.323 Match Criterion

38-6

H.323 Inspect Map

38-7

Phone Number Filtering

38-9

Add/Edit H.323 Policy Map (Security Level)

38-9

Add/Edit H.323 Policy Map (Details)

38-10

Add/Edit HSI Group

38-12

Add/Edit H.323 Map

38-12

MGCP Inspection

38-13

MGCP Inspection Overview

38-14

Select MGCP Map

38-16

MGCP Inspect Map

38-16

Gateways and Call Agents

38-17

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Add/Edit MGCP Policy Map

38-17

Add/Edit MGCP Group

38-18

RTSP Inspection

38-19

RTSP Inspection Overview

38-19

Using RealPlayer

38-20

Restrictions and Limitations

38-20

Select RTSP Map

38-21

RTSP Inspect Map

38-21

Add/Edit RTSP Policy Map

38-22

Add/Edit RTSP Inspect

38-22

SIP Inspection

38-23

SIP Inspection Overview

38-24

SIP Instant Messaging

38-24

Select SIP Map

38-25

SIP Class Map

38-26

Add/Edit SIP Traffic Class Map

38-27

Add/Edit SIP Match Criterion

38-27

SIP Inspect Map

38-29

Add/Edit SIP Policy Map (Security Level)

38-31

Add/Edit SIP Policy Map (Details)

38-32

Add/Edit SIP Inspect

38-34

Skinny (SCCP) Inspection

38-36

SCCP Inspection Overview

38-36

Supporting Cisco IP Phones

38-37

Restrictions and Limitations

38-37

Select SCCP (Skinny) Map

38-38

SCCP (Skinny) Inspect Map

38-38

Message ID Filtering

38-40

Add/Edit SCCP (Skinny) Policy Map (Security Level)

38-40

Add/Edit SCCP (Skinny) Policy Map (Details)

38-41

Add/Edit Message ID Filter

38-42

Configuring Inspection of Database and Directory Protocols

39-1

ILS Inspection

39-1

SQL*Net Inspection

39-2

Sun RPC Inspection

39-3

Sun RPC Inspection Overview

39-3

SUNRPC Server

39-3

Add/Edit SUNRPC Service

39-4


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C H A P T E R

41

C H A P T E R

42

Configuring Inspection for Management Application Protocols

40-1

DCERPC Inspection

40-1

DCERPC Overview

40-1

Select DCERPC Map

40-2

DCERPC Inspect Map

40-2

Add/Edit DCERPC Policy Map

40-4

GTP Inspection

40-5

GTP Inspection Overview

40-5

Select GTP Map

40-6

GTP Inspect Map

40-7

IMSI Prefix Filtering

40-8

Add/Edit GTP Policy Map (Security Level)

40-8

Add/Edit GTP Policy Map (Details)

40-9

Add/Edit GTP Map

40-11

RADIUS Accounting Inspection

40-12

RADIUS Accounting Inspection Overview

40-13

Select RADIUS Accounting Map

40-13

Add RADIUS Accounting Policy Map

40-14

RADIUS Inspect Map

40-14

RADIUS Inspect Map Host

40-15

RADIUS Inspect Map Other

40-15

RSH Inspection

40-16

SNMP Inspection

40-16

SNMP Inspection Overview

40-17

Select SNMP Map

40-17

SNMP Inspect Map

40-17

Add/Edit SNMP Map

40-18

XDMCP Inspection

40-18

Configuring Unified Communications

Information About Cisco Unified Communications Proxy Features

41-1

Information About the Adaptive Security Appliance in Cisco Unified Communications

41-1

TLS Proxy Applications in Cisco Unified Communications

41-3

Licensing for Cisco Unified Communications Proxy Features

41-4

Using the Cisco Unified Communication Wizard

42-1

Information the Cisco Unified Communication Wizard

42-1

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Licensing Requirements for the Unified Communication Wizard

42-3


42-3

Configuring the Mobility Advantage by using the Unified Communication Wizard

42-4

Configuring the Topology for the Cisco Mobility Advantage Proxy

42-5

Configuring the Server-Side Certificates for the Cisco Mobility Advantage Proxy

42-5

Configuring the Client-Side Certificates for the Cisco Mobility Advantage Proxy

42-6

Configuring the Presence Federation Proxy by using the Unified Communication Wizard

42-7

Configuring the Topology for the Cisco Presence Federation Proxy

42-8

Configuring the Local-Side Certificates for the Cisco Presence Federation Proxy

42-8

Configuring the Remote-Side Certificates for the Cisco Presence Federation Proxy

42-9

Configuring the UC-IME by using the Unified Communication Wizard

42-10

Configuring the Topology for the Cisco Intercompany Media Engine Proxy

42-11

Configuring the Private Network Settings for the Cisco Intercompany Media Engine Proxy

42-12

Adding a Cisco Unified Communications Manager Server for the UC-IME Proxy

42-13

Configuring the Public Network Settings for the Cisco Intercompany Media Engine Proxy

42-13

Configuring the Media Termination Address for the Cisco Intercompany Media Engine Proxy

42-14

Configuring the Local-Side Certificates for the Cisco Intercompany Media Engine Proxy

42-15

Configuring the Remote-Side Certificates for the Cisco Intercompany Media Engine Proxy

42-16

Working with Certificates in the Unified Communication Wizard

42-17

Exporting an Identity Certificate

42-17

Installing a Certificate

42-18

Generating a Certificate Signing Request (CSR) for a Unified Communications Proxy

42-18

Saving the Identity Certificate Request

42-19

Installing the ASA Identity Certificate on the Mobility Advantage Server

42-20

Installing the ASA Identity Certificate on the Presence Federation and Cisco Intercompany Media

Engine Servers

42-21

Configuring the Cisco Phone Proxy

43-1

Information About the Cisco Phone Proxy

43-1

Phone Proxy Functionality

43-1

Supported Cisco UCM and IP Phones for the Phone Proxy

43-3

Licensing Requirements for the Phone Proxy

43-4

Prerequisites for the Phone Proxy

43-5

Media Termination Instance Prerequisites

43-5

Certificates from the Cisco UCM

43-6

DNS Lookup Prerequisites

43-7

Cisco Unified Communications Manager Prerequisites

43-7

Access List Rules

43-7

NAT and PAT Prerequisites

43-8

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Prerequisites for IP Phones on Multiple Interfaces

43-8

7960 and 7940 IP Phones Support

43-9

Cisco IP Communicator Prerequisites

43-9

Prerequisites for Rate Limiting TFTP Requests

43-10

Rate Limiting Configuration Example

43-10

End-User Phone Provisioning

43-10

Ways to Deploy IP Phones to End Users

43-11

Phone Proxy Guidelines and Limitations

43-11

General Guidelines and Limitations

43-11

Media Termination Address Guidelines and Limitations

43-13

Configuring the Phone Proxy

43-13

Task Flow for Configuring the Phone Proxy

43-14

Creating the CTL File

43-14

Adding or Editing a Record Entry in a CTL File

43-15

Creating the Media Termination Instance

43-16

Creating the Phone Proxy Instance

43-17

Adding or Editing the TFTP Server for a Phone Proxy

43-19

Configuring Linksys Routers with UDP Port Forwarding for the Phone Proxy

43-20

Configuring Your Router

43-20

Feature History for the Phone Proxy

43-21

Configuring the TLS Proxy for Encrypted Voice Inspection

44-1

Information about the TLS Proxy for Encrypted Voice Inspection

44-1

Decryption and Inspection of Unified Communications Encrypted Signaling

44-2

Licensing for the TLS Proxy

44-3

Prerequisites for the TLS Proxy for Encrypted Voice Inspection

44-4

Configuring the TLS Proxy for Encrypted Voice Inspection

44-5

CTL Provider

44-5

Add/Edit CTL Provider

44-6

Configure TLS Proxy Pane

44-7

Adding a TLS Proxy Instance

44-8

Add TLS Proxy Instance Wizard – Server Configuration

44-9

Add TLS Proxy Instance Wizard – Client Configuration

44-10

Add TLS Proxy Instance Wizard – Other Steps

44-12

Edit TLS Proxy Instance – Server Configuration

44-12

Edit TLS Proxy Instance – Client Configuration

44-13

TLS Proxy

44-15

Add/Edit TLS Proxy

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45

C H A P T E R

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Feature History for the TLS Proxy for Encrypted Voice Inspection

44-17

Configuring Cisco Mobility Advantage

45-1

Information about the Cisco Mobility Advantage Proxy Feature

45-1

Cisco Mobility Advantage Proxy Functionality

45-1

Mobility Advantage Proxy Deployment Scenarios

45-2

Mobility Advantage Proxy Using NAT/PAT

45-4

Trust Relationships for Cisco UMA Deployments

45-5

Licensing for the Cisco Mobility Advantage Proxy Feature

45-6

Configuring Cisco Mobility Advantage

45-6

Task Flow for Configuring Cisco Mobility Advantage

45-7

Feature History for Cisco Mobility Advantage

45-7

Configuring Cisco Unified Presence

46-1

Information About Cisco Unified Presence

46-1

Architecture for Cisco Unified Presence for SIP Federation Deployments

46-1

Trust Relationship in the Presence Federation

46-3

Security Certificate Exchange Between Cisco UP and the Security Appliance

46-4

XMPP Federation Deployments

46-5

Configuration Requirements for XMPP Federation

46-5

Licensing for Cisco Unified Presence

46-7

Configuring Cisco Unified Presence Proxy for SIP Federation

46-7

Task Flow for Configuring Cisco Unified Presence Federation Proxy for SIP Federation

46-8

Feature History for Cisco Unified Presence

46-8

Configuring Cisco Intercompany Media Engine Proxy

47-1

Information About Cisco Intercompany Media Engine Proxy

47-1

Features of Cisco Intercompany Media Engine Proxy

47-1

How the UC-IME Works with the PSTN and the Internet

47-2

Tickets and Passwords

47-3

Call Fallback to the PSTN

47-5

Architecture and Deployment Scenarios for Cisco Intercompany Media Engine

47-5

Architecture

47-5

Basic Deployment

47-6

Off Path Deployment

47-7

Licensing for Cisco Intercompany Media Engine

47-8


47-9

Configuring Cisco Intercompany Media Engine Proxy

47-11

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C H A P T E R

49

Task Flow for Configuring Cisco Intercompany Media Engine

47-11

Configuring NAT for Cisco Intercompany Media Engine Proxy

47-12

Configuring PAT for the Cisco UCM Server

47-14

Creating Access Lists for Cisco Intercompany Media Engine Proxy

47-16

Creating the Media Termination Instance

47-17

Creating the Cisco Intercompany Media Engine Proxy

47-18

Creating Trustpoints and Generating Certificates

47-22

Creating the TLS Proxy

47-25

Enabling SIP Inspection for the Cisco Intercompany Media Engine Proxy

47-26

(Optional) Configuring TLS within the Local Enterprise

47-28

(Optional) Configuring Off Path Signaling

47-31

Configuring the Cisco UC-IMC Proxy by using the UC-IME Proxy Pane

47-32

Configuring the Cisco UC-IMC Proxy by using the Unified Communications Wizard

47-34

Feature History for Cisco Intercompany Media Engine Proxy

47-38

Configuring Connection Settings and QoS

Configuring Connection Settings

48-1

Information About Connection Settings

48-1

TCP Intercept and Limiting Embryonic Connections

48-2

Disabling TCP Intercept for Management Packets for Clientless SSL Compatibility

48-2

Dead Connection Detection (DCD)

48-2

TCP Sequence Randomization

48-2

TCP Normalization

48-3

TCP State Bypass

48-3

Licensing Requirements for Connection Settings

48-4


48-4

TCP State Bypass Guidelines and Limitations

48-5

Default Settings

48-5

Configuring Connection Settings

48-5

Task Flow For Configuring Configuration Settings (Except Global Timeouts)

48-6

Customizing the TCP Normalizer with a TCP Map

48-6

Configuring Connection Settings

48-8

Configuring Global Timeouts

48-9

Feature History for Connection Settings

48-11

Configuring QoS

49-1

Information About QoS

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Supported QoS Features

49-2

What is a Token Bucket?

49-2

Information About Policing

49-3

Information About Priority Queueing

49-3

Information About Traffic Shaping

49-4

How QoS Features Interact

49-4

DSCP and DiffServ Preservation

49-5

Configuring QoS

49-5

Creating the Standard Priority Queue for an Interface

49-5

Determining the Queue and TX Ring Limits

49-6

Configuring the Priority Queue

49-7

Creating a Policy for Standard Priority Queueing and/or Policing

49-7

Creating a Policy for Traffic Shaping and Hierarchical Priority Queueing

49-8

Configuring Advanced Network Protection

Configuring the Botnet Traffic Filter

50-1

Information About the Botnet Traffic Filter

50-1

Botnet Traffic Filter Address Categories

50-2

Botnet Traffic Filter Actions for Known Addresses

50-2

Botnet Traffic Filter Databases

50-2

Information About the Dynamic Database

50-2

Information About the Static Database

50-3

Information About the DNS Reverse Lookup Cache and DNS Host Cache

50-3

How the Botnet Traffic Filter Works

50-4

Licensing Requirements for the Botnet Traffic Filter

50-5


50-5

Default Settings

50-6

Configuring the Botnet Traffic Filter

50-6

Task Flow for Configuring the Botnet Traffic Filter

50-6

Configuring the Dynamic Database

50-7

Adding Entries to the Static Database

50-8

Enabling DNS Snooping

50-9

Enabling Traffic Classification and Actions for the Botnet Traffic Filter

50-10

Blocking Botnet Traffic Manually

50-12

Searching the Dynamic Database

50-13

Monitoring the Botnet Traffic Filter

50-13

Botnet Traffic Filter Syslog Messaging

50-13

Botnet Traffic Filter Monitor Panes

50-14


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Contents

C H A P T E R

51

C H A P T E R

52

Where to Go Next

50-15

Feature History for the Botnet Traffic Filter

50-15

Configuring Threat Detection

51-1

Information About Threat Detection

51-1

Configuring Basic Threat Detection Statistics

51-1

Information About Basic Threat Detection Statistics

51-2


51-2

Default Settings

51-3

Configuring Basic Threat Detection Statistics

51-4

Monitoring Basic Threat Detection Statistics

51-4

Feature History for Basic Threat Detection Statistics

51-4

Configuring Advanced Threat Detection Statistics

51-5

Information About Advanced Threat Detection Statistics

51-5


51-5

Default Settings

51-5

Configuring Advanced Threat Detection Statistics

51-5

Monitoring Advanced Threat Detection Statistics

51-7

Feature History for Advanced Threat Detection Statistics

51-8

Configuring Scanning Threat Detection

51-8

Information About Scanning Threat Detection

51-9


51-9

Default Settings

51-10

Configuring Scanning Threat Detection

51-10

Feature History for Scanning Threat Detection

51-11

Using Protection Tools

52-1

Preventing IP Spoofing

52-1

Configuring the Fragment Size

52-2

Show Fragment

52-2

Configuring TCP Options

52-3

TCP Reset Settings

52-4

Configuring IP Audit for Basic IPS Support

52-5

IP Audit Policy

52-5

Add/Edit IP Audit Policy Configuration

52-6

IP Audit Signatures

52-6

IP Audit Signature List

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Configuring Applications on SSMs and SSCs

Managing SSMs and SSCs

53-1

Information About SSMs and SSCs

53-1

Supported Applications

53-1

Information About Management Access

53-2

Sessioning to the Module

53-2

Using ASDM

53-2

Using SSH or Telnet

53-3

Other Uses for the Module Management Interface

53-3

Routing Considerations for Accessing the Management Interface

53-3


53-3

Default Settings

53-4

Configuring the SSC Management Interface

53-4

Password Troubleshooting

53-6

Where to Go Next

53-7

Feature History for the SSM and SSC

53-7

Configuring the IPS Application on the AIP SSM and SSC

54-1

Information About the AIP SSM and SSC

54-1

How the AIP SSM/SSC Works with the Adaptive Security Appliance

54-2

Operating Modes

54-2

Using Virtual Sensors (AIP SSM Only)

54-3

Differences Between the AIP SSM and the AIP SSC

54-4

Licensing Requirements for the AIP SSM/SSC

54-4


54-5

Configuring the AIP SSM/SSC

54-5

AIP SSM/SSC Task Overview

54-5

Configuring the Security Policy on the AIP SSM/SSC

54-6

Assigning Virtual Sensors to a Security Context (AIP SSM Only)

54-7

Diverting Traffic to the AIP SSM/SSC

54-8

Feature History for the AIP SSM/SSC

54-9

Configuring the Content Security and Control Application on the CSC SSM

55-1

Information About the CSC SSM

55-1

Determining What Traffic to Scan

55-3

Licensing Requirements for the CSC SSM

55-5

Prerequisites for the CSC SSM

55-5


Contents xxxix

Contents

C H A P T E R

56


55-6

Default Settings

55-6

Configuring the CSC SSM

55-7

Before Configuring the CSC SSM

55-7

Connecting to the CSC SSM

55-8

Determining Service Policy Rule Actions for CSC Scanning

55-9

Monitoring the CSC SSM

55-10

Threats

55-11

Live Security Events

55-11

Live Security Events Log

55-12

Software Updates

55-13

Resource Graphs

55-13

CSC CPU

55-13

CSC Memory

55-14

Where to Go Next

55-14


55-14

Feature History for the CSC SSM

55-15

Configuring Trend Micro Content Security

56-1

Information About the CSC SSM

56-2

Licensing Requirements for the CSC SSM

56-2

Prerequisites for the CSC SSM

56-2


56-3

Default Settings

56-3

CSC SSM Setup

56-4

Activation/License

56-4

IP Configuration

56-5

Host/Notification Settings

56-5

Management Access Host/Networks

56-6

Password

56-7

Restoring the Default Password

56-8

Wizard Setup

56-8

CSC Setup Wizard Activation Codes Configuration

56-9

CSC Setup Wizard IP Configuration

56-9

CSC Setup Wizard Host Configuration

56-9

CSC Setup Wizard Management Access Configuration

56-10

CSC Setup Wizard Password Configuration

56-10

CSC Setup Wizard Traffic Selection for CSC Scan

56-11

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CSC Setup Wizard Summary

56-12

Using the CSC SSM GUI

56-13

Web

56-13

Mail

56-14

SMTP Tab

56-14

POP3 Tab

56-15

File Transfer

56-15

Updates

56-16

Where to Go Next

56-16


56-17

Feature History for the CSC SSM

56-17

Configuring High Availability

Information About High Availability

57-1

Information About Failover and High Availability

57-1

Failover System Requirements

57-2

Hardware Requirements

57-2

Software Requirements

57-2

License Requirements

57-2

Failover and Stateful Failover Links

57-2

Failover Link

57-3

Stateful Failover Link

57-3

Failover Interface Speed for Stateful Links

57-4

Active/Active and Active/Standby Failover

57-5

Determining Which Type of Failover to Use

57-5

Stateless (Regular) and Stateful Failover

57-6

Stateless (Regular) Failover

57-6

Stateful Failover

57-6

Auto Update Server Support in Failover Configurations

57-8

Auto Update Process Overview

57-8

Monitoring the Auto Update Process

57-9

Failover Health Monitoring

57-10

Unit Health Monitoring

57-11

Interface Monitoring

57-11

Failover Feature/Platform Matrix

57-12

Failover Times by Platform

57-12


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58

C H A P T E R

59

Failover Messages

57-13

Failover System Messages

57-13

Debug Messages

57-13

SNMP

57-13

Using the High Availability and Scalability Wizard

58-1

Information About the High Availability and Scalability Wizard

58-1

Licensing Requirements for the High Availability and Scalability Wizard

58-1

Prerequisites for the High Availability and Scalability Wizard

58-2


58-2

Configuring Failover with the High Availability and Scalability Wizard

58-2

Accessing the High Availability and Scalability Wizard

58-3

Configuring Active/Active Failover with the High Availability and Scalability Wizard

58-3

Configuring Active/Standby Failover with the High Availability and Scalability Wizard

58-4

High Availability and Scalability Wizard Screens

58-5

Configuration Type

58-5

Failover Peer Connectivity and Compatibility Check

58-6

Change a Device to Multiple Mode

58-6

Security Context Configuration

58-7

Failover Link Configuration

58-7

State Link Configuration

58-7

Standby Address Configuration

58-8

Summary

58-9

Configuring VPN Cluster Load Balancing with the High Availability and Scalability Wizard

58-9

VPN Cluster Load Balancing Configuration

58-9

Feature History for the High Availability and Scalability Wizard

58-11

Configuring Active/Standby Failover

59-1

Information About Active/Standby Failover

59-1

Active/Standby Failover Overview

59-1

Primary/Secondary Status and Active/Standby Status

59-2

Device Initialization and Configuration Synchronization

59-2

Command Replication

59-3

Failover Triggers

59-3

Failover Actions

59-4

Optional Active/Standby Failover Settings

59-5

Licensing Requirements for Active/Standby Failover

59-5

Prerequisites for Active/Standby Failover

59-5

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59-5

Configuring Active/Standby Failover

59-6

Configuring Failover

59-6

Configuring Interface Standby Addresses

59-8

Configuring Interface Standby Addresses in Routed Firewall Mode

59-8

Configuring the Management Interface Standby Address in Transparent Firewall Mode

59-9

Configuring Optional Active/Standby Failover Settings

59-9

Disabling and Enabling Interface Monitoring

59-9

Configuring Failover Criteria

59-10

Configuring the Unit and Interface Health Poll Times

59-11

Configuring Virtual MAC Addresses

59-11

Controlling Failover

59-12

Forcing Failover

59-12

Disabling Failover

59-12

Restoring a Failed Unit

59-13

Monitoring Active/Standby Failover

59-14

Feature History for Active/Standby Failover

59-17

Configuring Active/Active Failover

60-1

Information About Active/Active Failover

60-1

Active/Active Failover Overview

60-1

Primary/Secondary Status and Active/Standby Status

60-2

Device Initialization and Configuration Synchronization

60-3

Command Replication

60-3

Replicated commands are not saved to the flash memory when replicated to the peer unit. They are added to the running configuration. Failover Triggers

60-4

Failover Actions

60-5

Optional Active/Active Failover Settings

60-6

Licensing Requirements for Active/Active Failover

60-6

Prerequisites for Active/Active Failover

60-6


60-7

Configuring Active/Active Failover

60-8

Failover-Multiple Mode, Security Context

60-8

Failover - Routed

60-8

Failover - Transparent

60-9

Failover-Multiple Mode, System

60-9

Failover > Setup Tab

60-10

Failover > Criteria Tab

60-12

Failover > Active/Active Tab

60-12

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Failover > MAC Addresses Tab

60-15

Controlling Failover

60-16

Forcing Failover

60-17

Disabling Failover

60-17

Restoring a Failed Unit or Failover Group

60-17

Monitoring Active/Active Failover

60-18

System

60-18

Failover Group 1 and Failover Group 2

60-19

Feature History for Active/Active Failover

60-19

Configuring VPN

SSL VPN Wizard

61-1

SSL VPN Connection Type

61-1

SSL VPN Interface

61-2

User Authentication

61-2

Group Policy

61-3

Bookmark List

61-3

IP Address Pools and Client Image

61-4

Summary

61-4

VPN

62-1

VPN Wizard

62-2

VPN Overview

62-2

VPN Tunnel Type

62-3

Remote Site Peer

62-4

IKE Policy

62-5

IPsec Rule

62-6

Hosts and Networks

62-7

Remote Access Client

62-8

VPN Client Authentication Method and Name

62-9

Client Authentication

62-10

New Authentication Server Group

62-11

User Accounts

62-11

Address Pool

62-12

Attributes Pushed to Client

62-13

IPsec Settings (Optional)

62-13

Summary

62-14

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Configuring IKE, Load Balancing, and NAC

63-1

Setting IKE Parameters

63-1

Creating IKE Policies

63-4

Add/Edit IKE Policy

63-5

Assignment Policy

63-7

Address Pools

63-8

Add/Edit IP Pool

63-8

Configuring IPsec

63-9

Adding Crypto Maps

63-10

Creating an IPsec Rule/Tunnel Policy (Crypto Map) - Basic Tab

63-11

Creating IPsec Rule/Tunnel Policy (Crypto Map) - Advanced Tab

63-13

Creating IPsec Rule/Traffic Selection Tab

63-14

Pre-Fragmentation

63-16

Edit IPsec Pre-Fragmentation Policy

63-17

IPsec Transform Sets

63-18

Add/Edit Transform Set

63-18

Configuring Load Balancing

63-19

Eligible Clients

63-20

Enabling Load Balancing

63-20

Creating Virtual Clusters

63-20

Mixed Cluster Scenarios

63-21

Comparing Load Balancing to Failover

63-22

Load Balancing Prerequisites

63-23

Setting Global NAC Parameters

63-25

Configuring Network Admission Control Policies

63-26

Add/Edit Posture Validation Exception

63-29

General VPN Setup

64-1

Client Software

64-1

Edit Client Update Entry

64-3

Default Tunnel Gateway

64-4

Group Policies

64-5

Add/Edit External Group Policy

64-6

Add AAA Server Group

64-6

Adding or Editing a Remote Access Internal Group Policy, General Attributes

64-7

Configuring the Portal for a Group Policy

64-10

Configuring Customization for a Group Policy

64-11

Adding or Editing a Site-to-Site Internal Group Policy

64-12

Contents

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Browse Time Range

64-13

Add/Edit Time Range

64-14

Add/Edit Recurring Time Range

64-14

ACL Manager

64-15

Standard ACL

64-15

Extended ACL

64-16

Add/Edit/Paste ACE

64-17

Browse Source/Destination Address

64-19

Browse Source/Destination Port

64-19

Add TCP Service Group

64-20

Browse ICMP

64-21

Add ICMP Group

64-21

Browse Other

64-22

Add Protocol Group

64-22

Add/Edit Internal Group Policy > Servers

64-23

Add/Edit Internal Group Policy > IPsec Client

64-27

Client Access Rules

64-28

Add/Edit Client Access Rule

64-28

Add/Edit Internal Group Policy > Client Configuration Dialog Box

64-29

Add/Edit Internal Group Policy > Client Configuration > General Client Parameters

64-29

View/Config Banner

64-31

Add/Edit Internal Group Policy > Client Configuration > Cisco Client Parameters

64-31

Add or Edit Internal Group Policy > Advanced > IE Browser Proxy

64-32

Add/Edit Standard Access List Rule

64-33

Add/Edit Internal Group Policy > Client Firewall

64-34

Add/Edit Internal Group Policy > Hardware Client

64-36

Add/Edit Server and URL List

64-39

Add/Edit Server or URL

64-39

Configuring AnyConnect (SSL) VPN Client Connections

64-39

Using AnyConnect Client Profiles

64-41

Importing an AnyConnect Client Profile

64-42

Exporting an AnyConnect Client Profile

64-43

Exempting AnyConnect Traffic from Network Address Translation

64-43

Configuring SSL VPN Connections

64-48

Setting the Basic Attributes for an SSL VPN Connection

64-49

Setting Advanced Attributes for a Connection Profile

64-50

Setting General Attributes for an AnyConnect SSL VPN Connection

64-51

Setting Client Addressing Attributes for an AnyConnect SSL VPN Connection

64-52

Configuring Authentication Attributes for an SSL VPN Connection Profile

64-52


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Configuring Secondary Authentication Attributes for an SSL VPN Connection Profile

64-54

Configuring Authorization Attributes for an SSL VPN Connection Profile

64-56

Adding or Editing Content to a Script for Certificate Pre-Fill-Username

64-57

Configuring AnyConnect Secure Mobility

64-60

Add or Edit MUS Access Control

64-61

Configuring Clientless SSL VPN Connections

64-61

Add or Edit Clientless SSL VPN Connections

64-62

Add or Edit Clientless SSL VPN Connections > Basic

64-62

Add or Edit Clientless SSL VPN Connections > Advanced

64-63

Add or Edit Clientless SSL VPN Connections > Advanced > General

64-63

Add or Edit Clientless or SSL VPN Client Connection Profile or IPsec Connection Profiles> Advanced

> Authentication

64-64

Assign Authentication Server Group to Interface

64-64

Add or Edit SSL VPN Connections > Advanced > Authorization

64-65

Assign Authorization Server Group to Interface

64-66

Add or Edit SSL VPN Connections > Advanced > SSL VPN

64-66

Add or Edit Clientless SSL VPN Connections > Advanced > Clientless SSL VPN

64-67

Add or Edit Clientless SSL VPN Connections > Advanced > NetBIOS Servers

64-68

Configure DNS Server Groups

64-69

Add or Edit Clientless SSL VPN Connections > Advanced > Clientless SSL VPN

64-70

IPsec Remote Access Connection Profiles

64-70

Add or Edit an IPsec Remote Access Connection Profile

64-71

Add or Edit IPsec Remote Access Connection Profile Basic

64-71

Mapping Certificates to IPsec or SSL VPN Connection Profiles

64-72

Site-to-Site Connection Profiles

64-77

Add/Edit Site-to-Site Connection

64-77

Adding or Editing a Site-to-Site Tunnel Group

64-78

Crypto Map Entry

64-80

Crypto Map Entry for Static Peer Address

64-80

Managing CA Certificates

64-81

Install Certificate

64-82

Configure Options for CA Certificate

64-82

Revocation Check Dialog Box

64-82

Add/Edit Remote Access Connections > Advanced > General

64-83

Configuring Client Addressing

64-84

Add/Edit SSL VPN Connections > Advanced > Accounting

64-88

Add/Edit Tunnel Group > General > Client Address Assignment

64-88

Add/Edit Tunnel Group > General > Advanced

64-89

Add/Edit Tunnel Group > IPsec for Remote Access > IPsec

64-90

Cisco ASA 5500 Series Configuration Guide using ASDM xlvii

Contents

Add/Edit Tunnel Group for Site-to-Site VPN

64-91

Add/Edit Tunnel Group > PPP

64-92

Add/Edit Tunnel Group > IPsec for LAN to LAN Access > General > Basic

64-93

Add/Edit Tunnel Group > IPsec for LAN to LAN Access > IPsec

64-94

Clientless SSL VPN Access > Connection Profiles > Add/Edit > General > Basic

64-96

Configuring Internal Group Policy IPsec Client Attributes

64-97

Configuring Client Addressing for SSL VPN Connections

64-99

Assign Address Pools to Interface

64-99

Select Address Pools

64-100

Add or Edit an IP Address Pool

64-100

Authenticating SSL VPN Connections

64-101

System Options

64-101

Configuring SSL VPN Connections, Advanced

64-102

Configuring Split Tunneling

64-102

Zone Labs Integrity Server

64-102

Easy VPN Remote

64-104

Advanced Easy VPN Properties

64-106

AnyConnect Essentials

64-108

DTLS Settings

64-109

SSL VPN Client Settings

64-109

Add/Replace SSL VPN Client Image

64-111

Upload Image

64-111

Add/Edit SSL VPN Client Profiles

64-112

Upload Package

64-113

Bypass Interface Access List

64-113

C H A P T E R

65

Configuring Dynamic Access Policies

65-1

Understanding VPN Access Policies

65-1

DAP Support for Remote Access Connection Types

65-4

DAP and AAA

65-4

DAP and Endpoint Security

65-5

DAP Connection Sequence

65-7

Test Dynamic Access Policies

65-8

Add/Edit Dynamic Access Policies

65-10

Add/Edit AAA Attributes

65-15

Retrieving Active Directory Groups

65-18

Add/Edit Endpoint Attributes

65-19

Guide

65-22

Syntax for Creating Lua EVAL Expressions

65-22

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66

C H A P T E R

67

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The DAP CheckAndMsg Function

65-24

Additional Lua Functions

65-26

CheckAndMsg with Custom Function Example

65-28

Further Information on Lua

65-28

Operator for Endpoint Category

65-28

DAP Examples

65-28

Clientless SSL VPN End User Set-up

66-1

Requiring Usernames and Passwords

66-1

Communicating Security Tips

66-2

Configuring Remote Systems to Use Clientless SSL VPN Features

66-2

Capturing Clientless SSL VPN Data

66-7

Creating a Capture File

66-8

Using a Browser to Display Capture Data

66-8

Clientless SSL VPN

67-1

Security Precautions

67-1

Understanding Clientless SSL VPN System Requirements

67-3

Clientless SSL VPN Access

67-3

ACLs

67-5

Add ACL

67-6

Add/Edit ACE

67-6

Configuring the Setup for Cisco Secure Desktop

67-7

Configuring Application Helper

67-10

Clock Accuracy for SharePoint Access

67-12

Auto Signon

67-12

Configuring Session Settings

67-14

Java Code Signer

67-15

Content Cache

67-15

Content Rewrite

67-16

Java Code Signer

67-18

Encoding

67-18

Web ACLs

67-21

Configuring Port Forwarding

67-22

Why Port Forwarding?

67-22

Port Forwarding Requirements and Restrictions

67-23

Configuring DNS for Port Forwarding

67-24


Contents xlix

Contents

Add/Edit Port Forwarding List

67-26

Add/Edit Port Forwarding Entry

67-26

Configuring the Use of External Proxy Servers

67-27

Configuring Proxy Bypass

67-28

SSO Servers

67-30

Configuring SiteMinder and SAML Browser Post Profile

67-31

SAML POST SSO Server Configuration

67-31

Adding the Cisco Authentication Scheme to SiteMinder

67-32

Add/Edit SSO Servers

67-33

Configuring Smart Tunnel Access

67-33

About Smart Tunnels

67-34

Why Smart Tunnels?

67-35

Smart Tunnel Requirements and Limitations

67-35

General Requirements and Limitations

67-35

Windows Requirements and Limitations

67-36

Mac OS Requirements and Limitations

67-36

Configuring a Smart Tunnel (Lotus example)

67-36

Simplifying Configuration of Which Applications to Tunnel

67-37

Add or Edit Smart Tunnel List

67-38

Add or Edit Smart Tunnel Entry

67-39

Add or Edit Smart Tunnel Auto Sign-on Server List

67-41

Add or Edit Smart Tunnel Auto Sign-on Server Entry

67-41

Logging Off Smart Tunnel

67-42

Without Using Notification Icon

67-43

Using the Notification Icon

67-43

Customizing the Clientless SSL VPN User Experience

67-44

Customizing the Logon Page

67-44

Customizing the Logon Page with the Customization Editor

67-45

Replacing the Logon Page with your own Fully Customized Page

67-46

Customizing the Portal Page

67-49

Customizing the Logout Page

67-50

Add Customization Object

67-51

Import/Export Customization Object

67-51

Creating XML-Based Portal Customization Objects and URL Lists

67-52

Understanding the XML Customization File Structure

67-52

Customization Example

67-58

Using the Customization Template

67-60

The Customization Template

67-60

Help Customization

67-73

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68

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Import/Export Application Help Content

67-75

Configuring Browser Access to Client-Server Plug-ins

67-76

About Installing Browser Plug-ins

67-77

RDP Plug-in ActiveX Debug Quick Reference

67-78

Plug-in Requirements and Restrictions

67-78

Preparing the Security Appliance for a Plug-in

67-78

Installing Plug-ins Redistributed by Cisco

67-79

Assembling and Installing Third-Party Plug-ins—Example: Citrix

67-81

POST Plug-ins for Homepage SSO and Application-only Portals

67-83

Configuring POST Plug-ins

67-83

Configuring and Applying the POST URL

67-84

Language Localization

67-84

Customizing the AnyConnect Client

67-88

Customizing AnyConnect by Importing Resource Files

67-88

Customizing AnyConnect with you own GUI and Scripts

67-89

Importing your own GUI as a Binary Executable

67-90

Importing Scripts

67-91

Customizing AnyConnect GUI Text and Messages

67-93

Customizing the Installer Program using Installer Transforms

67-94

Sample Transform

67-94

Localizing the Install Program using Installer Transforms

67-95

Import/Export Language Localization

67-96

Configuring Bookmarks

67-98

Add/Edit Bookmark List

67-98

Add Bookmark Entry

67-99

Import/Export Bookmark List

67-100

Configure GUI Customization Objects (Web Contents)

67-101

Import/Export Web Content

67-101

Add/Edit Post Parameter

67-102

E-Mail Proxy

68-1

Configuring E-Mail Proxy

68-1

AAA

68-2

POP3S Tab

68-2

IMAP4S Tab

68-4

SMTPS Tab

68-6

Access

68-7

Edit E-Mail Proxy Access

68-9

Authentication

68-9


Contents li

Contents

C H A P T E R

69

C H A P T E R

70

Default Servers

68-11

Delimiters

68-13

Configuring SSL Settings

69-1

SSL

69-1

Edit SSL Certificate

69-2

SSL Certificates

69-3

Monitoring VPN

70-1

VPN Connection Graphs

70-1

IPSec Tunnels

70-1

Sessions

70-2

VPN Statistics

70-3

Sessions

70-3

Sessions Details

70-6

Cluster Loads

70-8

Crypto Statistics

70-9

Compression Statistics

70-9

Encryption Statistics

70-10

Global IKE/IPSec Statistics

70-11

NAC Session Summary

70-11

Protocol Statistics

70-12

VLAN Mapping Sessions

70-13

SSO Statistics for Clientless SSL VPN Session

70-13

VPN Connection Status for the Easy VPN Client

70-15

Monitoring

P A R T

15

C H A P T E R

71

Configuring Logging

71-1

Information About Logging

71-1

Logging in Multiple Context Mode

71-2

Analyzing Syslog Messages

71-2

Syslog Message Format

71-3

Severity Levels

71-3

Message Classes and Range of Syslog IDs

71-4

Filtering Syslog Messages

71-4

Sorting in the Log Viewers

71-4

Using Custom Message Lists

71-5

Licensing Requirements for Logging

71-5

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OL-20339-01

Contents

Prerequisites for Logging

71-5


71-6

Configuring Logging

71-6

Enabling Logging

71-6

Configuring an Output Destination

71-7

Sending Syslog Messages to an External Syslog Server

71-7

Configuring FTP Settings

71-8

Configuring Logging Flash Usage

71-9

Configuring Syslog Messaging

71-9

Editing Syslog ID Settings

71-10

Including a Device ID in Non-EMBLEM Formatted Syslog Messages

71-10

Sending Syslog Messages to the Internal Log Buffer

71-11

Sending Syslog Messages to an E-mail Address

71-12

Adding or Editing E-Mail Recipients

71-12

Configuring the Remote SMTP Server

71-12

Applying Message Filters to a Logging Destination

71-12

Applying Logging Filters

71-13

Adding or Editing a Message Class and Severity Filter

71-14

Adding or Editing a Syslog Message ID Filter

71-15

Sending Syslog Messages to the Console Port

71-15

Sending Syslog Messages to a Telnet or SSH Session

71-15

Creating a Custom Event List

71-15

Generating Syslog Messages in EMBLEM Format to a Syslog Server

71-16

Adding or Editing Syslog Server Settings

71-17

Generating Syslog Messages in EMBLEM Format to Other Output Destinations

71-17

Changing the Amount of Internal Flash Memory Available for Logs

71-18

Configuring the Logging Queue

71-18

Sending All Syslog Messages in a Class to a Specified Output Destination

71-19

Enabling Secure Logging

71-19

Including the Device ID in Non-EMBLEM Format Syslog Messages

71-19

Including the Date and Time in Syslog Messages

71-20

Disabling a Syslog Message

71-20

Changing the Severity Level of a Syslog Message

71-20

Limiting the Rate of Syslog Message Generation

71-20

Assigning or Changing Rate Limits for Individual Syslog Messages

71-21

Adding or Editing the Rate Limit for a Syslog Message

71-21

Editing the Rate Limit for a Syslog Severity Level

71-21

Log Monitoring

71-22

Filtering Syslog Messages Through the Log Viewers

71-22

Cisco ASA 5500 Series Configuration Guide using ASDM liii

Contents

Editing Filtering Settings

71-24

Feature History for Logging

71-25

C H A P T E R

72

Configuring NetFlow Secure Event Logging (NSEL)

72-1

Information About NSEL

72-1

Using NSEL and Syslog Messages

72-2

Licensing Requirements for NSEL

72-3

Prerequisites for NSEL

72-3


72-3

Configuring NSEL

72-4

Using NetFlow

72-4

Matching NetFlow Events to Configured Collectors

72-5

Monitoring NSEL

72-6

Where to Go Next

72-6


72-6

Related Documents

72-8

RFCs

72-8

Feature History for NSEL

72-8

C H A P T E R

73

Configuring SNMP

73-1

Information about SNMP

73-1

Information About SNMP Terminology

73-2

Information About MIBs and Traps

73-2

SNMP Version 3

73-3

SNMP Version 3 Overview

73-3

Security Models

73-3

SNMP Groups

73-4

SNMP Users

73-4

SNMP Hosts

73-4

Implementation Differences Between Adaptive Security Appliances and the Cisco IOS

73-4

Licensing Requirements for SNMP

73-4

Prerequisites for SNMP

73-5


73-5

Configuring SNMP

73-6

Enabling SNMP

73-6

Configuring an SNMP Management Station

73-6

Configuring SNMP Traps

73-7

Compiling Cisco Syslog MIB Files

73-8

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C H A P T E R

74

P A R T

16

C H A P T E R

75

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Using SNMP Version 1 or 2c

73-9

Using SNMP Version 3

73-9

Monitoring SNMP

73-10

SNMP Syslog Messaging

73-11

SNMP Monitoring

73-11

Where to Go Next

73-12


73-12

RFCs for SNMP Version 3

73-12

MIBs

73-12

Application Services and Third-Party Tools

73-14

Feature History for SNMP

73-14

Configuring Smart Call Home

74-1

Information About Smart Call Home

74-1


74-2

Licensing Requirements for Smart Call Home

74-2

Detailed Steps

74-2

Smart Call Home Monitoring

74-5

Feature History for Smart Call Home

74-6

System Administration

Managing Software and Configurations

75-1

Managing Files

75-1

Accessing the File Management Tool

75-1

Managing Mount Points

75-2

Adding or Editing a CIFS/FTP Mount Point

75-3

Accessing a CIFS Mount Point

75-4

Transferring Files

75-5

Saving the Running Configuration to a TFTP Server

75-6

Configuring Auto Update

75-7

Setting the Polling Schedule

75-8

Adding or Editing an Auto Update Server

75-9

Configuring the Boot Image/Configuration Settings

75-9

Adding a Boot Image

75-10

Upgrading Software from Your Local Computer

75-10

Upgrading Software from the Cisco.com Wizard

75-11

Scheduling a System Restart

75-12


Contents lv

Contents

Backing Up and Restoring Configurations, Images, and Profiles

75-13

Backing Up Configurations

75-13

Restoring Configurations

75-17

Downgrading Your Software

75-19

Information About Activation Key Compatibility

75-19

Performing the Downgrade

75-20

C H A P T E R

76

Troubleshooting

76-1

Testing Your Configuration

76-1

Pinging Adaptive Security Appliance Interfaces

76-1

Passing Traffic Through the Adaptive Security Appliance

76-3

Verifying ASA Configuration and Operation, and Testing Interfaces Using Ping

76-3

Pinging From an Adaptive Security Appliance Interface

76-4

Pinging to an Adaptive Security Appliance Interface

76-5

Pinging Through the Adaptive Security Appliance Interface

76-5

Troubleshooting the Ping Tool

76-5

Using the Ping Tool

76-5

Determining Packet Routing with Traceroute

76-6

Tracing Packets with Packet Tracer

76-7

Other Troubleshooting Tools

76-8

Configuring and Running Captures with the Packet Capture Wizard

76-8

Ingress Traffic Selector

76-10

Egress Traffic Selector

76-10

Buffers

76-10

Summary

76-11

Run Captures

76-11

Save Captures

76-11

Sending an Administrator’s Alert to Clientless SSL VPN Users

76-12

Saving an Internal Log Buffer to Flash

76-12

Viewing and Copying Logged Entries with the ASDM Java Console

76-12

Common Problems

76-13

Reference

P A R T

17

A P P E N D I X

A

Addresses, Protocols, and Ports

A-1

IPv4 Addresses and Subnet Masks

A-1

Classes

A-1

Private Networks

A-2

Subnet Masks

A-2

Cisco ASA 5500 Series Configuration Guide using ASDM lvi OL-20339-01

Contents

A P P E N D I X

B

Determining the Subnet Mask

A-3

Determining the Address to Use with the Subnet Mask

A-3

IPv6 Addresses

A-5

IPv6 Address Format

A-5

IPv6 Address Types

A-6

Unicast Addresses

A-6

Multicast Address

A-8

Anycast Address

A-9

Required Addresses

A-10

IPv6 Address Prefixes

A-10

Protocols and Applications

A-11

TCP and UDP Ports

A-11

Local Ports and Protocols

A-14

ICMP Types

A-15

Configuring an External Server for Authorization and Authentication

B-1

Understanding Policy Enforcement of Permissions and Attributes

B-2

Configuring an External LDAP Server

B-3

Organizing the Security Appliance for LDAP Operations

B-3

Searching the Hierarchy

B-4

Binding the Security Appliance to the LDAP Server

B-5

Login DN Example for Active Directory

B-5

Defining the Security Appliance LDAP Configuration

B-6

Supported Cisco Attributes for LDAP Authorization

B-6

Cisco AV Pair Attribute Syntax

B-13

Cisco AV Pairs ACL Examples

B-15

Active Directory/LDAP VPN Remote Access Authorization Use Cases

B-16

User-Based Attributes Policy Enforcement

B-18

Placing LDAP users in a specific Group-Policy

B-20

Enforcing Static IP Address Assignment for AnyConnect Tunnels

B-22

Enforcing Dial-in Allow or Deny Access

B-25

Enforcing Logon Hours and Time-of-Day Rules

B-28

Configuring an External RADIUS Server

B-30

Reviewing the RADIUS Configuration Procedure

B-30

Security Appliance RADIUS Authorization Attributes

B-30

Security Appliance IETF RADIUS Authorization Attributes

B-38

Configuring an External TACACS+ Server

B-39

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Cisco ASA 5500 Series Configuration Guide using ASDM lvii

Contents

G

L O S S A R Y

I

N D E X

lviii


OL-20339-01

About This Guide

This preface introduces


and includes the following sections:

•

Document Objectives, page lix

•

•

•

•

Audience, page lix

Related Documentation, page lx

Document Conventions, page lx

Obtaining Documentation, Obtaining Support, and Security Guidelines, page lx

Document Objectives

The purpose of this guide is to help you configure the adaptive security appliance using ASDM. This guide does not cover every feature, but describes only the most common configuration scenarios.

This guide applies to the Cisco ASA 5500 series adaptive security appliances. Throughout this guide, the term “adaptive security appliance” applies generically to all supported models, unless specified otherwise. The PIX 500 security appliances are not supported.

Note

Although ASDM 6.3 supports many ASA versions, the ASDM 6.3 documentation and online help only include features for ASA versions for which support was introduced in ASDM 6.3. For older ASA versions, you might find that using the ASDM 6.3 documentation is inaccurate for your older feature set.

Instead, refer to the ASDM guide in which support for your platform version was added (see the

Cisco

ASA 5500 Series and PIX 500 Series Security Appliance Hardware and Software Compatibility

for the minimum supported version of ASDM for each ASA version). Although the specific information about the ASDM GUI might be inaccurate in that guide, the platform feature set is documented correctly.

Audience

This guide is for network managers who perform any of the following tasks:

•

Manage network security

•

•

Install and configure firewalls/adaptive security appliances

Configure VPNs

OL-20339-01

Cisco ASA 5500 Series Configuration Guide using ASDM lix

•

Configure intrusion detection software

Related Documentation

For more information, see

Navigating the Cisco ASA 5500 Series Documentation

at http://www.cisco.com/en/US/docs/security/asa/roadmap/asaroadmap.html

.

About This Guide

Document Conventions

Command descriptions use these conventions:

•

•

•

•

Braces ({ }) indicate a required choice.

Square brackets ([ ]) indicate optional elements.

Vertical bars ( | ) separate alternative, mutually exclusive elements.

Boldface

indicates commands and keywords that are entered literally as shown.

•

Italics

indicate arguments for which you supply values.

Examples use these conventions:

•

•

•

Examples depict screen displays and the command line in

Information you need to enter in examples is shown in

boldface screen

font.

Variables for which you must supply a value are shown in screen

font.

italic screen

font.

Note

Means

reader take note

. Notes contain helpful suggestions or references to material not covered in the manual.

Obtaining Documentation, Obtaining Support, and Security

Guidelines

For information on obtaining documentation, obtaining support, providing documentation feedback, security guidelines, and also recommended aliases and general Cisco documents, see the monthly

What’s New in Cisco Product Documentation

, which also lists all new and revised Cisco technical documentation, at: http://www.cisco.com/en/US/docs/general/whatsnew/whatsnew.html

lx


OL-20339-01

P

A R T

1

Getting Started and General Information

C H A P T E R

1

Introduction to the Cisco ASA 5500 Series

Adaptive Security Appliance

The adaptive security appliance combines advanced stateful firewall and VPN concentrator functionality in one device, and for some models, an integrated intrusion prevention module called the AIP SSM/SSC or an integrated content security and control module called the CSC SSM. The adaptive security appliance includes many advanced features, such as multiple security contexts (similar to virtualized firewalls), transparent (Layer 2) firewall or routed (Layer 3) firewall operation, advanced inspection engines, IPSec VPN, SSL VPN, and clientless SSL VPN support, and many more features.

Note

Although ASDM 6.3 supports many ASA versions, the ASDM 6.3 documentation and online help only include features for ASA 8.3. For older ASA versions, you might find that using the ASDM 6.3 documentation is inaccurate for your older feature set. Instead, refer to the ASDM guide in which support for your platform version was added (see

Cisco ASA 5500 Series and PIX 500 Series Security

Appliance Hardware and Software Compatibility

for the minimum supported version of ASDM for each

ASA version). Although the specific information about the ASDM GUI might be inaccurate in that guide, the platform feature set is documented correctly.

This chapter includes the following sections:

•

•

ASDM Client Operating System and Browser Requirements, page 1-1

ASA 5500 Model Support, page 1-2

•

•

•

•

Module Support, page 1-2

VPN Specifications, page 1-3

New Features, page 1-3

Unsupported Commands, page 1-13

•

•

•

Firewall Functional Overview, page 1-15

VPN Functional Overview, page 1-19

Security Context Overview, page 1-20

ASDM Client Operating System and Browser Requirements


1-1 OL-20339-01

Chapter 1 Introduction to the Cisco ASA 5500 Series Adaptive Security Appliance

ASA 5500 Model Support

Table 1-1 lists the supported and recommended client operating systems and Java for ASDM.

Operating System and Browser Requirements Table 1-1

Operating System

Microsoft Windows (English and Japanese):

•

•

7

Vista

•

•

2003 Server

XP

Apple Macintosh OS X:

•

10.6

•

•

10.5

10.4

Red Hat Enterprise Linux 5 (GNOME or

KDE):

•

Desktop

•

Desktop with Workstation

1.

Obtain Sun Java from java.sun.com

.

Browser

Internet Explorer Firefox

6.0 or above 1.5 or above

No support

N/A

1.5 or above

1.5 or above

Safari

No support

2.0 or above

N/A

Sun Java SE

Plug-in

1

•

5.0 (1.5.0)

•

6.0

•

•

5.0 (1.5.0)

6.0

•

•

5.0 (1.5.0)

6.0

ASA 5500 Model Support

For a complete list of supported ASA models and ASA software versions for this release, see

Cisco ASA

5500 Series and PIX 500 Series Security Appliance Hardware and Software Compatibility

: http://www.cisco.com/en/US/docs/security/asa/compatibility/asamatrx.html

Module Support

The adaptive security appliance supports the following module types:

•

•

Security Services Cards (SSCs)

Security Services Modules (SSMs)

1-2


OL-20339-01


VPN Specifications

Table 1-2 shows the modules supported by each model:

Table 1-2 Module Support

Model

ASA 5505

ASA 5510

ASA 5520

ASA 5540

ASA 5550

ASA 5580

Modules Supported

Advanced Inspection and Prevention (AIP) SSC-5

AIP SSM-10 and -20

CSC SSM-10 and -20

4GE SSM

AIP SSM-10, -20, and -40

CSC SSM-10 and -20

4GE SSM

AIP SSM-10, -20, and -40

CSC SSM-10 and -20

1

4GE SSM

No support (the 4GE SSM is built-in and not user-removable)

No support

1.

The CSC SSM licenses support up to 1000 users while the Cisco ASA 5540 Series appliance can support significantly more users. If you deploy CSC SSM with an ASA 5540 adaptive security appliance, be sure to configure the security appliance to send the CSC SSM only the traffic that should be scanned.

VPN Specifications

See the

Supported VPN Platforms, Cisco ASA 5500 Series

at http://www.cisco.com/en/US/docs/security/asa/compatibility/vpn-platforms-83.html

.

New Features

This section includes the following topics:

•

New Features in Version 6.3(2)/8.3(2), page 1-3

•

New Features in Version 6.3(1)/8.3(1), page 1-6

Note

New, changed, and deprecated syslog messages are listed in

Cisco ASA 5500 Series System Log

Messages

.

New Features in Version 6.3(2)/8.3(2)

OL-20339-01


1-3


New Features

Table 1-3 lists the new features for ASDM Version 6.3(2). All features apply only to ASA Version 8.3(2), unless otherwise noted.

New Features for ASDM Version 6.3(2)/ASA Version 8.3(2) (Unless Otherwise Noted) Table 1-3

Feature

Monitoring Features

Enhanced logging and connection blocking

Description

When you configure a syslog server to use TCP, and the syslog server is unavailable, the adaptive security appliance blocks new connections that generate syslog messages until the server becomes available again (for example, VPN, firewall, and cut-through-proxy connections). This feature has been enhanced to also block new connections when the logging queue on the adaptive security appliance is full; connections resume when the logging queue is cleared.

This feature was added for compliance with Common Criteria EAL4+. Unless required, we recommend allowing new connections when syslog messages cannot be sent. To allow new connections, configure the syslog server to use UDP or check the

Allow user traffic to pass when TCP syslog server is down

check box on the Configuration > Device Management >

Logging > Syslog Servers pane.

Syslog message filtering and sorting

The following syslog messages were introduced: 414005, 414006, 414007, and 414008

No ASDM screens were modified.

Support has been added for the following:

•

Syslog message filtering based on multiple text strings that correspond to various columns

•

•

Creation of custom filters

Column sorting of messages. For detailed information, see the

Cisco ASA 5500 Series

Configuration Guide using ASDM

.

The following screens were modified:

Monitoring > Logging > Real-Time Log Viewer > View

Monitoring > Logging > Log Buffer Viewer > View

Clearing syslog messages for the CSC SSM

This feature interoperates with all ASA versions.

Support for clearing syslog messages has been added in the Latest CSC Security Events pane.

The following screen was modified: Home > Content Security.


Remote Access Features

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New Features

Table 1-3 New Features for ASDM Version 6.3(2)/ASA Version 8.3(2) (Unless Otherwise Noted) (continued)

Feature

Hardware processing for large modulus operations

(2048-bit RSA certificate and DH5)

Description

This feature lets you switch large modulus operations from software to hardware. It applies only to the ASA models 5510, 5520, 5540, and 5550.

The switch to hardware accelerates the following:

•

2048-bit RSA public key certificate processing.

•

Diffie Hellman Group 5 key generation.

We recommend that you enable this feature if it is necessary to improve the connections per second. Depending on the load, it might have a limited performance impact on SSL throughput. We recommend that you use this feature during a low-use or maintenance period to minimize a temporary packet loss that can occur during the transition of processing from software to hardware.

The following commands were introduced or modified:

crypto engine large-mod-accel

,

clear configure crypto engine

,

show running-config crypto engine

, and

show running-config crypto

.

In ASDM, use the Command Line Interface tool to enter the

crypto engine large-mod-accel

command.

Microsoft Internet Explorer proxy lockdown control

Also available in Version 8.2(3).

Enabling this feature hides the Connections tab in Microsoft Internet Explorer for the duration of an AnyConnect VPN session. Disabling the feature leaves the display of the Connections tab unchanged; the default setting for the tab can be shown or hidden, depending on the user registry settings.

The following command was introduced:

msie-proxy lockdown

.

Secondary password enhancement

In ASDM, use the Command Line Interface tool to enter this command.

Also available in Version 8.2(3).

You can now configure SSL VPN support for a common secondary password for all authentications or use the primary password as the secondary password.

The following screen was modified: Configuration > Remote Access VPN > Clientless SSL

Access > Connection Profiles > Add/Edit Clientless SSL VPN Connection Profile > Advanced

> Secondary Authentication.

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New Features


Description Feature

General Features

No Payload Encryption image for export

For export to some countries, payload encryption cannot be enabled on the Cisco ASA 5500 series. For version 8.3(2), you can now install a No Payload Encryption image

(asa832-npe-k8.bin) on the following models:

•

ASA 5505

•

•

•

•

ASA 5510

ASA 5520

ASA 5540

ASA 5550

•

Features that are disabled in the No Payload Encryption image include:

•

Unified Communications.

•

Strong encryption for VPN (DES encryption is still available for VPN).

VPN load balancing (note that the GUI is still present; the feature will not function, however).

•

•

Downloading of the dynamic database for the Botnet Traffic Filer (Static black and whitelists are still supported. Note that the GUI is still present; the feature will not function, however.).

Management protocols requiring strong encryption, including SSL, SSHv2, and SNMPv3.

You can, however, use SSL or SNMPv3 using base encryption (DES). Also, SSHv1 and

SNMPv1 and v2 are still available.

If you attempt to install a Strong Encryption (3DES/AES) license, you see the following warning:

WARNING: Strong encryption types have been disabled in this image; the

VPN-3DES-AES license option has been ignored.

New Features in Version 6.3(1)/8.3(1)

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New Features

Table 1-4 lists the new features for ASDM Version 6.3(1). All features apply only to ASA Version 8.3(1), unless otherwise noted.

New Features for ASDM Version 6.3(1)/ASA Version 8.3(1) (Unless Otherwise Noted) Table 1-4

Feature

Remote Access Features

Description

Smart Tunnel Enhancements Logoff enhancement—Smart tunnel can now be logged off when all browser windows have been closed (parent affinity), or you can right click the notification icon in the system tray and confirm log out.

Tunnel Policy—An administrator can dictate which connections go through the VPN gateway and which do not. An end user can browse the Internet directly while accessing company internal resources with smart tunnel if the administrator chooses.

Simplified configuration of which applications to tunnel—When a smart tunnel is required, a user no longer needs to configure a list of processes that can access smart tunnel and in turn access certain web pages. An “enable smart tunnel” check box for either a bookmark or standalone application allows for an easier configuration process.

Group policy home page—Using a check box in ASDM, administrators can now specify their home page in group policy in order to connect via smart tunnel.

Newly Supported Platforms for Browser-based VPN

The following screen was modified: Configuration > Remote Access VPN > AAA/Local Users

> Local Users > Edit > VPN Policy > Clientless SSL VPN.

Release 8.3(1) provides browser-based (clientless) VPN access from the following newly supported platforms:

•

•

•

•

Windows 7 x86 (32-bit) and x64 (64-bit) via Internet Explorer 8.x and Firefox 3.x

Windows Vista x64 via Internet Explorer 7.x/8.x, or Firefox 3.x.

Windows XP x64 via Internet Explorer 6.x/7.x/8.x and Firefox 3.x

Mac OS 10.6.x 32- and 64-bit via Safari 4.x and Firefox 3.x.

Firefox 2.x is likely to work, although we no longer test it.

Release 8.3(1) introduces browser-based support for 64-bit applications on Mac OS 10.5.

Release 8.3(1) now supports smart tunnel access on all 32-bit and 64-bit Windows OSs supported for browser-based VPN access, Mac OS 10.5 running on an Intel processor only, and

Mac OS 10.6.x. The adaptive security appliance does not support port forwarding on 64-bit

OSs.

Browser-based VPN access does not support Windows Shares (CIFS) Web Folders on

Windows 7, Vista, and Internet Explorer 8. An ActiveX version of the RDP plug-in is unavailable for 64-bit browsers.

Note

Windows 2000 and Mac OS X 10.4 are no longer supported for browser-based access.

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New Features


Feature

IPv6 support for IKEv1

LAN-to-LAN VPN connections

Description

For LAN-to-LAN connections using mixed IPv4 and IPv6 addressing, or all IPv6 addressing, the adaptive security appliance supports VPN tunnels if both peers are Cisco ASA 5500 series adaptive security appliances, and if both inside networks have matching addressing schemes

(both IPv4 or both IPv6).

Specifically, the following topologies are supported when both peers are Cisco ASA 5500 series adaptive security appliances:

•

The adaptive security appliances have IPv4 inside networks and the outside network is

IPv6 (IPv4 addresses on the inside interfaces and IPv6 addresses on the outside interfaces).

•

•


IPv4 (IPv6 addresses on the inside interface and IPv4 addresses on the outside interfaces).


IPv6 (IPv6 addresses on the inside and outside interfaces).

Plug-in for AnyConnect

Profile Editor

SSL VPN Portal

Customization Editor

Note

The defect CSCtd38078 currently prevents the Cisco ASA 5500 series from connecting to a Cisco IOS device as the peer device of a LAN-to-LAN connection.

The following screens were modified or introduced:

Wizards > IPsec VPN Wizard, Configuration > Site-to-Site VPN > Connection Profiles

Configuration > Site-to-Site VPN > Connection Profiles > Basic > Add IPsec Site-to-Site

Connection Profile

Configuration > Site-to-Site VPN > Group Policies

Configuration > Site-to-Site VPN > Group Policies > Edit Internal Group Policy

Configuration > Site-to-Site VPN > Advanced > Crypto Maps

Configuration > Site-to-Site VPN > Advanced > Crypto Maps > Add > Create IPsec Rule

Configuration > Site-to-Site VPN > Advanced > ACL Manager

The AnyConnect Profile Editor is a convenient GUI-based configuration tool you can use to configure the AnyConnect 2.5 or later client profile, an XML file containing settings that control client features. Previously, you could only change profile settings manually by editing the XML tags in the profile file. The AnyConnect Profile Editor is a plug-in binary file named anyconnectprof.sgz packaged with the ASDM image and installed in the root directory of disk0:/ in the flash memory on the adaptive security appliance. This design allows you to update the editor to be compatible with new AnyConnect features available in new client releases.

You can rebrand and customize the screens presented to clientless SSL VPN users using the new Edit Customization Object window in ASDM. You can customize the logon, portal and logout screens, including corporate logos, text messages, and the general layout. Previously, the customization feature was embedded in the adaptive security appliance software image.

Moving it to ASDM provides greater usability for this feature and future enhancements.

The following screen was modified: Configuration > Remote Access VPN > Clientless SSL

VPN Access > Portal > Customization.

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New Features


Feature

Usability Improvements for

Remote Access VPN

Description

ASDM provides a step-by-step guide to configuring Clientless SSL VPN, AnyConnect SSL

VPN Remote Access, or IPsec Remote Access using the ASDM Assistant. The ASDM

Assistant is more comprehensive than the VPN wizards, which are designed only to get you up and running.

The following screen was modified: Configuration > Remote Access VPN > Introduction >

ASDM Assistant.

Firewall Features

Interface-Independent

Access Policies

Network and Service

Objects

You can now configure access rules that are applied globally, as well as access rules that are applied to an interface. If the configuration specifies both a global access policy and interface-specific access policies, the interface-specific policies are evaluated before the global policy.

The following screen was modified: Configuration > Firewall > Access Rules.

You can now create named network objects that you can use in place of a host, a subnet, or a range of IP addresses in your configuration and named service objects that you can use in place of a protocol and port in your configuration. You can then change the object definition in one place, without having to change any other part of your configuration. This release introduces support for network and service objects in the following features:

•

•

NAT

Access rules

•

Note

Network object groups

ASDM used network objects internally in previous releases; this feature introduces platform support for network objects.

Object-group Expansion

Rule Reduction

NAT Simplification


Configuration > Firewall > Objects > Network Objects/Groups, Configuration > Firewall >

Objects > Service Objects/Groups

Configuration > Firewall > NAT Rules, Configuration > Firewall > Access Rules

Significantly reduces the network object-group expansion while maintaining a satisfactory level of packet classification performance.

The following screen was modified: Configuration > Firewall > Access Rules > Advanced.

The NAT configuration was completely redesigned to allow greater flexibility and ease of use.

You can now configure NAT using auto NAT, where you configure NAT as part of the attributes of a network object, and manual NAT, where you can configure more advanced NAT options.


Configuration > Firewall > Objects > Network Objects/Group

Configuration > Firewall > NAT Rules

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New Features


Feature

Use of Real IP addresses in access lists instead of translated addresses

Description

When using NAT, mapped addresses are no longer required in an access list for many features.

You should always use the real, untranslated addresses when configuring these features. Using the real address means that if the NAT configuration changes, you do not need to change the access lists.

The following features that use access lists now use real IP addresses. These features are automatically migrated to use real IP addresses when you upgrade to 8.3, unless otherwise noted.

•

Access rules

•

•

•

•

Service policy rules

Botnet Traffic Filter

AAA rules

WCCP redirect.

Threat Detection

Enhancements

Note

WCCP is not automatically migrated when you upgrade to 8.3.

You can now customize the number of rate intervals for which advanced statistics are collected.

The default number of rates was changed from 3 to 1. For basic statistics, advanced statistics, and scanning threat detection, the memory usage was improved.

The following screen was modified: Configuration > Firewall > Threat Detection.

Unified Communication Features

SCCP v19 support The IP phone support in the Cisco Phone Proxy feature was enhanced to include support for version 19 of the SCCP protocol on the list of supported IP phones.

Cisco Intercompany Media

Engine Proxy

Cisco Intercompany Media Engine (UC-IME) enables companies to interconnect on-demand, over the Internet with advanced features made available by VoIP technologies. Cisco

Intercompany Media Engine allows for business-to-business federation between Cisco Unified

Communications Manager clusters in different enterprises by utilizing peer-to-peer, security, and SIP protocols to create dynamic SIP trunks between businesses. A collection of enterprises work together to end up looking like one large business with inter-cluster trunks between them.


SIP Inspection Support for

IME

Wizards > Unified Communications Wizard > Cisco Intercompany Media Engine Proxy

Configuration > Firewall > Unified Communications, and then click UC-IME Proxy

Configuration > Firewall > Service Policy Rules > Add/Edit Service Policy Rule > Rule

Actions > Select SIP Inspection Map

SIP inspection has been enhance to support the new Cisco Intercompany Media Engine

(UC-IME) Proxy.

The following screen was modified: Configuration > Firewall > Service Policy Rules >

Add/Edit Service Policy Rule > Rule Actions > Select SIP Inspection Map.

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New Features


Feature

Unified Communication

Wizard

Enhanced Navigation for

Unified Communication

Features

Description

The Unified Communications wizard guides you through the complete configuration and automatically configures required aspects for the following proxies: Cisco Mobility Advantage

Proxy, Cisco Presence Federation Proxy, Cisco Intercompany Media Engine proxy.

Additionally, the Unified Communications wizard automatically configures other required aspects of the proxies.


Wizards > Unified Communications Wizard

Configuration > Firewall > Unified Communications

The Unified Communications proxy features, such as the Phone Proxy, TLS Proxy, CTL File, and CTL Provider pages, are moved from under the Objects category in the left Navigation panel. to the new Unified Communications category. In addition, this new category contains pages for the new Unified Communications wizard and the UC-IME Proxy page.


Routing Features

Route map support ASDM has added enhanced support for static and dynamic routes.

The following screen was modified: Configuration > Device Setup > Routing > Route Maps.


Monitoring Features

Time Stamps for Access List

Hit Counts

Displays the timestamp, along with the hash value and hit count, for a specified access list.

The following screen was modified: Configuration > Firewall > Access Rules. (The timestamp appears when you hover the mouse over a cell in the Hits column.)

High Performance

Monitoring for ASDM

You can now enable high performance monitoring for ASDM to show the top 200 hosts connected through the adaptive security appliance. Each entry of a host contains the IP address of the host and the number of connections initiated by the host, and is updated every 120 seconds.

The following screen was introduced: Home > Firewall Dashboard > Top 200 Hosts.

Licensing Features

Non-identical failover licenses

Failover licenses no longer need to be identical on each unit. The license used for both units is the combined license from the primary and secondary units.

Note

For the ASA 5505 and 5510 adaptive security appliances, both units require the

Security Plus license; the Base license does not support failover, so you cannot enable failover on a standby unit that only has the Base license.

The following screen was modified: Configuration > Device Management > Licensing >

Activation Key.

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New Features


Feature

Stackable time-based licenses

Intercompany Media Engine

License

The IME license was introduced.

Multiple time-based licenses active at the same time

You can now install multiple time-based licenses, and have one license per feature active at a time.

Discrete activation and deactivation of time-based licenses.

Description

Time-based licenses are now stackable. In many cases, you might need to renew your time-based license and have a seamless transition from the old license to the new one. For features that are only available with a time-based license, it is especially important that the license not expire before you can apply the new license. The adaptive security appliance allows you to

stack

time-based licenses so you do not have to worry about the license expiring or about losing time on your licenses because you installed the new one early. For licenses with numerical tiers, stacking is only supported for licenses with the same capacity, for example, two 1000-session SSL VPN licenses. You can view the state of the licenses at Configuration >

Device Management > Licensing > Activation Key.


Activation Key.

You can now activate or deactivate time-based licenses using a command.

The following command was modified:

activation-key

[

activate

|

deactivate

].


Activation Key.

General Features

Master Passphrase The master passphrase feature allows you to securely store plain text passwords in encrypted format. It provides a master key that is used to universally encrypt or mask all passwords, without changing any functionality. The Backup/Restore feature supports the master passphrase.

The following screens were introduced:

Configuration > Device Management > Advanced > Master Passphrase

Configuration > Device Management > Device Administration > Master Passphrase

ASDM Features

Upgrade Software from

Cisco.com Wizard

Backup/Restore

Enhancements

The Upgrade Software from Cisco.com wizard has changed to allow you to automatically upgrade ASDM and the adaptive security appliance to more current versions. Note that this feature is only available in single mode and, in multiple context mode, in the System execution space. It is not available in a context.

The following screen was modified: Tools > Check for ASA/ASDM Updates.


The Backup Configurations pane was re-ordered and re-grouped so you can choose the files you want to backup more easily. A Backup Progress pane was added allowing you to visually measure the progress of the backup. And you will see significant performance improvement when using backup or restore.

The following screen was modified: Tools > Backup Configurations or Tools > Restore

Configurations.


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Unsupported Commands


ASDM supports almost all commands available for the adaptive adaptive security appliance, but ASDM ignores some commands in an existing configuration. Most of these commands can remain in your configuration; see Tools > Show Commands Ignored by ASDM on Device for more information.


•

•

•

•

Ignored and View-Only Commands, page 1-13

Effects of Unsupported Commands, page 1-14

Discontinuous Subnet Masks Not Supported, page 1-14

Interactive User Commands Not Supported by the ASDM CLI Tool, page 1-14

Ignored and View-Only Commands

Table 1-5 lists commands that ASDM supports in the configuration when added through the CLI, but that cannot be added or edited in ASDM. If ASDM ignores the command, it does not appear in the ASDM

GUI at all. If the command is view-only, then it appears in the GUI, but you cannot edit it.

Table 1-5 List of Unsupported Commands

Unsupported Commands capture coredump dhcp-server

(tunnel-group name general-attributes)

eject established failover timeout ipv6 nd prefix pager pim accept-register route-map prefix-list service-policy global set metric sysopt nodnsalias

ASDM Behavior

Ignored.

Ignored. This can be configured only using the

CLI.

ASDM only allows one setting for all DHCP servers.

Unsupported.

Ignored.

Ignored.

Unsupported.

Ignored.

Ignored. You can configure only the

list

option using ASDM.

Ignored if not used in an OSPF area.

Ignored if it uses a

match access-list

class. For example: access-list myacl line 1 extended permit ip any any class-map mycm match access-list mycl policy-map mypm class mycm inspect ftp service-policy mypm global

Ignored.

Ignored.

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1-13



Table 1-5 List of Unsupported Commands

(continued)

Unsupported Commands sysopt uauth allow-http-cache terminal

ASDM Behavior

Ignored.

Ignored.

Effects of Unsupported Commands

If ASDM loads an existing running configuration and finds other unsupported commands, ASDM operation is unaffected. To view the unsupported commands, choose Tools > Show Commands Ignored by ASDM on Device.

Discontinuous Subnet Masks Not Supported

ASDM does not support discontinuous subnet masks such as 255.255.0.255. For example, you cannot use the following: ip address inside 192.168.2.1 255.255.0.255

Interactive User Commands Not Supported by the ASDM CLI Tool

The ASDM CLI tool does not support interactive user commands. If you enter a CLI command that requires interactive confirmation, ASDM prompts you to enter “[yes/no]” but does not recognize your input. ASDM then times out waiting for your response.

For example:

1.

2.

3.

From the ASDM Tools menu, click

Command Line Interface

.

Enter the

crypto key generate rsa

command.

ASDM generates the default 1024-bit RSA key.

Enter the

crypto key generate rsa

command again.

Instead of regenerating the RSA keys by overwriting the previous one, ASDM displays the following error:

Do you really want to replace them? [yes/no]:WARNING: You already have RSA ke0000000000000$A key

Input line must be less than 16 characters in length.

%Please answer 'yes' or 'no'.

Do you really want to replace them [yes/no]:

%ERROR: Timed out waiting for a response.

ERROR: Failed to create new RSA keys names <Default-RSA-key>

Workaround

:

•

•

You can configure most commands that require user interaction by means of the ASDM panes.

For CLI commands that have a

noconfirm

option, use this option when entering the CLI command.

For example:

crypto key generate rsa noconfirm

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Firewall Functional Overview


Firewalls protect inside networks from unauthorized access by users on an outside network. A firewall can also protect inside networks from each other, for example, by keeping a human resources network separate from a user network. If you have network resources that need to be available to an outside user, such as a web or FTP server, you can place these resources on a separate network behind the firewall, called a

demilitarized zone

(DMZ). The firewall allows limited access to the DMZ, but because the DMZ only includes the public servers, an attack there only affects the servers and does not affect the other inside networks. You can also control when inside users access outside networks (for example, access to the Internet), by allowing only certain addresses out, by requiring authentication or authorization, or by coordinating with an external URL filtering server.

When discussing networks connected to a firewall, the

outside

network is in front of the firewall, the

inside

network is protected and behind the firewall, and a

DMZ

, while behind the firewall, allows limited access to outside users. Because the adaptive security appliance lets you configure many interfaces with varied security policies, including many inside interfaces, many DMZs, and even many outside interfaces if desired, these terms are used in a general sense only.


•

•

•

Security Policy Overview, page 1-15

Firewall Mode Overview, page 1-18

Stateful Inspection Overview, page 1-18

Security Policy Overview

A security policy determines which traffic is allowed to pass through the firewall to access another network. By default, the adaptive security appliance allows traffic to flow freely from an inside network

(higher security level) to an outside network (lower security level). You can apply actions to traffic to customize the security policy. This section includes the following topics:

•

•

•

•

•

•

•

•

•

•

•

•

•

Permitting or Denying Traffic with Access Rules, page 1-16

Applying NAT, page 1-16

Protecting from IP Fragments, page 1-16

Using AAA for Through Traffic, page 1-16

Applying HTTP, HTTPS, or FTP Filtering, page 1-16

Applying Application Inspection, page 1-16

Sending Traffic to the Advanced Inspection and Prevention Security Services Module, page 1-16

Sending Traffic to the Content Security and Control Security Services Module, page 1-17

Applying QoS Policies, page 1-17

Applying Connection Limits and TCP Normalization, page 1-17

Enabling Threat Detection, page 1-17

Enabling the Botnet Traffic Filter, page 1-17

Configuring Cisco Unified Communications, page 1-18

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Permitting or Denying Traffic with Access Rules

You can apply an access rule to limit traffic from inside to outside, or allow traffic from outside to inside.

For transparent firewall mode, you can also apply an EtherType access list to allow non-IP traffic.

Applying NAT

Some of the benefits of NAT include the following:

•

You can use private addresses on your inside networks. Private addresses are not routable on the

Internet.

•

•

NAT hides the local addresses from other networks, so attackers cannot learn the real address of a host.

NAT can resolve IP routing problems by supporting overlapping IP addresses.

Protecting from IP Fragments

The adaptive security appliance provides IP fragment protection. This feature performs full reassembly of all ICMP error messages and virtual reassembly of the remaining IP fragments that are routed through the adaptive security appliance. Fragments that fail the security check are dropped and logged. Virtual reassembly cannot be disabled.

Using AAA for Through Traffic

You can require authentication and/or authorization for certain types of traffic, for example, for HTTP.

The adaptive security appliance also sends accounting information to a RADIUS or TACACS+ server.

Applying HTTP, HTTPS, or FTP Filtering

Although you can use access lists to prevent outbound access to specific websites or FTP servers, configuring and managing web usage this way is not practical because of the size and dynamic nature of the Internet. We recommend that you use the adaptive security appliance in conjunction with a separate server running one of the following Internet filtering products:

•

•

Websense Enterprise

Secure Computing SmartFilter

Applying Application Inspection

Inspection engines are required for services that embed IP addressing information in the user data packet or that open secondary channels on dynamically assigned ports. These protocols require the adaptive security appliance to do a deep packet inspection.

Sending Traffic to the Advanced Inspection and Prevention Security Services Module

If your model supports the AIP SSM for intrusion prevention, then you can send traffic to the AIP SSM for inspection. The AIP SSM is an intrusion prevention services module that monitors and performs real-time analysis of network traffic by looking for anomalies and misuse based on an extensive, embedded signature library. When the system detects unauthorized activity, it can terminate the specific connection, permanently block the attacking host, log the incident, and send an alert to the device


1-16 OL-20339-01



manager. Other legitimate connections continue to operate independently without interruption. For more information, see

Configuring the Cisco Intrusion Prevention System Sensor Using the Command Line

Interface

.

Sending Traffic to the Content Security and Control Security Services Module

If your model supports it, the CSC SSM provides protection against viruses, spyware, spam, and other unwanted traffic. It accomplishes this by scanning the FTP, HTTP, POP3, and SMTP traffic that you configure the adaptive adaptive security appliance to send to it.

Applying QoS Policies

Some network traffic, such as voice and streaming video, cannot tolerate long latency times. QoS is a network feature that lets you give priority to these types of traffic. QoS refers to the capability of a network to provide better service to selected network traffic.

Applying Connection Limits and TCP Normalization

You can limit TCP and UDP connections and embryonic connections. Limiting the number of connections and embryonic connections protects you from a DoS attack. The adaptive security appliance uses the embryonic limit to trigger TCP Intercept, which protects inside systems from a DoS attack perpetrated by flooding an interface with TCP SYN packets. An embryonic connection is a connection request that has not finished the necessary handshake between source and destination.

TCP normalization is a feature consisting of advanced TCP connection settings designed to drop packets that do not appear normal.

Enabling Threat Detection

You can configure scanning threat detection and basic threat detection, and also how to use statistics to analyze threats.

Basic threat detection detects activity that might be related to an attack, such as a DoS attack, and automatically sends a system log message.

A typical scanning attack consists of a host that tests the accessibility of every IP address in a subnet (by scanning through many hosts in the subnet or sweeping through many ports in a host or subnet). The scanning threat detection feature determines when a host is performing a scan. Unlike IPS scan detection that is based on traffic signatures, the adaptive security appliance scanning threat detection feature maintains an extensive database that contains host statistics that can be analyzed for scanning activity.

The host database tracks suspicious activity such as connections with no return activity, access of closed service ports, vulnerable TCP behaviors such as non-random IPID, and many more behaviors.

You can configure the adaptive security appliance to send system log messages about an attacker or you can automatically shun the host.

Enabling the Botnet Traffic Filter

Malware is malicious software that is installed on an unknowing host. Malware that attempts network activity such as sending private data (passwords, credit card numbers, key strokes, or proprietary data) can be detected by the Botnet Traffic Filter when the malware starts a connection to a known bad IP

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1-17



address. The Botnet Traffic Filter checks incoming and outgoing connections against a dynamic database of known bad domain names and IP addresses (the blacklist), and then logs any suspicious activity. When you see syslog messages about the malware activity, you can take steps to isolate and disinfect the host.

Configuring Cisco Unified Communications

The Cisco ASA 5500 Series appliances are a strategic platform to provide proxy functions for unified communications deployments. The purpose of a proxy is to terminate and reoriginate connections between a client and server. The proxy delivers a range of security functions such as traffic inspection, protocol conformance, and policy control to ensure security for the internal network. An increasingly popular function of a proxy is to terminate encrypted connections in order to apply security policies while maintaining confidentiality of connections.

Firewall Mode Overview

The adaptive security appliance runs in two different firewall modes:

•

•

Routed

Transparent

In routed mode, the adaptive security appliance is considered to be a router hop in the network.

In transparent mode, the adaptive security appliance acts like a “bump in the wire,” or a “stealth firewall,” and is not considered a router hop. The adaptive security appliance connects to the same network on its inside and outside interfaces.

You might use a transparent firewall to simplify your network configuration. Transparent mode is also useful if you want the firewall to be invisible to attackers. You can also use a transparent firewall for traffic that would otherwise be blocked in routed mode. For example, a transparent firewall can allow multicast streams using an EtherType access list.

Stateful Inspection Overview

All traffic that goes through the adaptive security appliance is inspected using the Adaptive Security

Algorithm and either allowed through or dropped. A simple packet filter can check for the correct source address, destination address, and ports, but it does not check that the packet sequence or flags are correct.

A filter also checks every packet against the filter, which can be a slow process.

Note

The TCP state bypass feature allows you to customize the packet flow. See the

“TCP State Bypass” section on page 48-3 .

A stateful firewall like the adaptive security appliance, however, takes into consideration the state of a packet:

•

Is this a new connection?

If it is a new connection, the adaptive security appliance has to check the packet against access lists and perform other tasks to determine if the packet is allowed or denied. To perform this check, the first packet of the session goes through the “session management path,” and depending on the type of traffic, it might also pass through the “control plane path.”

The session management path is responsible for the following tasks:

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VPN Functional Overview

•

–

–

–

Performing the access list checks

Performing route lookups

Allocating NAT translations (xlates)

–

Establishing sessions in the “fast path”

Some packets that require Layer 7 inspection (the packet payload must be inspected or altered) are passed on to the control plane path. Layer 7 inspection engines are required for protocols that have two or more channels: a data channel, which uses well-known port numbers, and a control channel, which uses different port numbers for each session. These protocols include FTP, H.323, and SNMP.

Is this an established connection?

If the connection is already established, the adaptive security appliance does not need to re-check packets; most matching packets can go through the “fast” path in both directions. The fast path is responsible for the following tasks:

–

–

–

–

IP checksum verification

Session lookup

TCP sequence number check

NAT translations based on existing sessions

–

Layer 3 and Layer 4 header adjustments

For UDP or other connectionless protocols, the adaptive security appliance creates connection state information so that it can also use the fast path.

Data packets for protocols that require Layer 7 inspection can also go through the fast path.

Some established session packets must continue to go through the session management path or the control plane path. Packets that go through the session management path include HTTP packets that require inspection or content filtering. Packets that go through the control plane path include the control packets for protocols that require Layer 7 inspection.

VPN Functional Overview

A VPN is a secure connection across a TCP/IP network (such as the Internet) that appears as a private connection. This secure connection is called a tunnel. The adaptive security appliance uses tunneling protocols to negotiate security parameters, create and manage tunnels, encapsulate packets, transmit or receive them through the tunnel, and unencapsulate them. The adaptive security appliance functions as a bidirectional tunnel endpoint: it can receive plain packets, encapsulate them, and send them to the other end of the tunnel where they are unencapsulated and sent to their final destination. It can also receive encapsulated packets, unencapsulate them, and send them to their final destination. The adaptive security appliance invokes various standard protocols to accomplish these functions.

The adaptive security appliance performs the following functions:

•

Establishes tunnels

•

•

•

•

•

Negotiates tunnel parameters

Authenticates users

Assigns user addresses

Encrypts and decrypts data

Manages security keys

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1-19


Security Context Overview

•

Manages data transfer across the tunnel

•

Manages data transfer inbound and outbound as a tunnel endpoint or route r

The adaptive security appliance invokes various standard protocols to accomplish these functions.

Security Context Overview

You can partition a single adaptive security appliance into multiple virtual devices, known as security contexts. Each context is an independent device, with its own security policy, interfaces, and administrators. Multiple contexts are similar to having multiple standalone devices. Many features are supported in multiple context mode, including routing tables, firewall features, IPS, and management.

Some features are not supported, including VPN and dynamic routing protocols.

In multiple context mode, the adaptive security appliance includes a configuration for each context that identifies the security policy, interfaces, and almost all the options you can configure on a standalone device. The system administrator adds and manages contexts by configuring them in the system configuration, which, like a single mode configuration, is the startup configuration. The system configuration identifies basic settings for the adaptive security appliance. The system configuration does not include any network interfaces or network settings for itself; rather, when the system needs to access network resources (such as downloading the contexts from the server), it uses one of the contexts that is designated as the admin context.

The admin context is just like any other context, except that when a user logs into the admin context, then that user has system administrator rights and can access the system and all other contexts.

Note

You can run all your contexts in routed mode or transparent mode; you cannot run some contexts in one mode and others in another.

Multiple context mode supports static routing only.

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C H A P T E R

2

Getting Started

This chapter describes how to get started with your adaptive security appliance. This chapter includes the following sections:

•

Configuring the Security Appliance for ASDM Access, page 2-1

•

•

•

•

Starting ASDM, page 2-1

Factory Default Configurations, page 2-5

Getting Started With the Configuration, page 2-8

Using the Command Line Interface, page 2-8

Configuring the Security Appliance for ASDM Access

If you want to use ASDM to configure the adaptive security appliance and you have a factory default configuration, you can connect to the default management address by pointing your browser or the

ASDM launcher to the IP address in the following URL: https://192.168.1.1/admin

With the factory default configuration, clients on the 192.168.1.0/24 inside network can access ASDM.

To allow other clients to access ASDM, see the

“Configuring Device Access for ASDM, Telnet, or SSH” section on page 32-1 .

See the following Ethernet connection guidelines when using the factory default configurations:

•

ASA 5505—The switch port to which you connect to ASDM can be any port, except for Ethernet

0/0.

•

ASA 5510 and higher —The interface to which you connect to ASDM is Management 0/0.

For more information, see the

“Factory Default Configurations” section on page 2-5 . If you do not have

a factory default configuration, see the

Cisco ASA 5500 Series Configuration Guide using the CLI

for instructions to access the CLI and the

setup

command to perform minimum initial configuration.

Starting ASDM

This section describes how to start ASDM according to one of the following methods:

•

•

Downloading the ASDM Launcher, page 2-2

Starting ASDM from the ASDM Launcher, page 2-2

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2-1

Chapter 2 Getting Started

Starting ASDM

•

•

Using ASDM in Demo Mode, page 2-3

Starting ASDM from a Web Browser, page 2-4

Downloading the ASDM Launcher

The ASDM Launcher is for Windows only. The ASDM Launcher avoids double authentication and certificate dialog boxes, launches more quickly, and caches previously entered IP addresses and usernames.

To download the ASDM launcher, perform the following steps:

Step 1

Step 2

On the ASDM Welcome screen, click the applicable button to download the ASDM Launcher installation file.

Double-click the

asdm-launcher.exe

file.

Note

In transparent firewall mode, enter the management IP address. Be sure to enter

https

, not

http

.

Step 3

Step 4

Click

OK

or

Yes

to all prompts, including the name and password prompt. Leave the name and password blank.

The installer downloads to your computer.

Run the installer to install the ASDM Launcher.

Starting ASDM from the ASDM Launcher

To start ASDM from the ASDM Launcher, perform the following steps:

Step 1

Step 2

Step 3

Double-click the Cisco ASDM Launcher shortcut on your desktop, or open it from the

Start

menu.

Alternatively, from the ASDM Welcome screen, you can click

Run Startup Wizard

to configure

ASDM.

Enter or choose the adaptive adaptive security appliance IP address or hostname to which you want to connect. To clear the list of IP addresses, click the trash can icon next to the Device/IP Address/Name field.

Enter your username and your password, and then click

OK

.

If there is a new version of ASDM on the adaptive adaptive security appliance, the ASDM Launcher automatically downloads the new version and requests that you update the current version before starting

ASDM.

Note

If you are using the factory default configuration, you do not need to have a username or password. Leave these fields blank to login to ASDM.

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Starting ASDM

Using ASDM in Demo Mode

The ASDM Demo Mode, a separately installed application, lets you run ASDM without having a live device available. In this mode, you can do the following:

•

Perform configuration and selected monitoring tasks via ASDM as though you were interacting with a real device.

•

•

Demonstrate ASDM or adaptive security appliance features using the ASDM interface.

Perform configuration and monitoring tasks with the CSC SSM.

•

Obtain simulated monitoring and logging data, including real-time syslog messages. The data shown is randomly generated; however, the experience is identical to what you would see when you are connected to a real device.

This mode has been updated to support the following features:

•

•

•

•

•

•

For global policies, an adaptive security appliance in single, routed mode and intrusion prevention

For object NAT, an adaptive security appliance in single, routed mode and a firewall DMZ.

This mode does not support the following:

•

Saving changes made to the configuration that appear in the GUI.

•

•

•

•

For the Botnet Traffic Filter, an adaptive security appliance in single, routed mode and security contexts.

Site-to-Site VPN with IPv6 (Clientless SSL VPN and IPsec VPN)

Promiscuous IDS (intrusion prevention)

Unified Communication Wizard

File or disk operations.

Historical monitoring data.

Non-administrative users.

These features:

–

File menu:

Save Running Configuration to Flash

Save Running Configuration to TFTP Server

Save Running Configuration to Standby Unit

–

Save Internal Log Buffer to Flash

Clear Internal Log Buffer

Tools menu:

Command Line Interface

Ping

File Management

Update Software

File Transfer

Upload Image from Local PC

System Reload

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2-3


Starting ASDM

•

–

Toolbar/Status bar > Save

–

–

Configuration > Interface > Edit Interface > Renew DHCP Lease

Configuring a standby device after failover

Operations that cause a rereading of the configuration, in which the GUI reverts to the original configuration:

–

Switching contexts

–

–

Making changes in the Interface pane

NAT pane changes

–

Clock pane changes

To run ASDM in Demo Mode, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Download the ASDM Demo Mode installer, asdm-demo-

version

.msi, from the following location: http://www.cisco.com/cisco/web/download/index.html.

Double-click the installer to install the software.

Double-click the Cisco ASDM Launcher shortcut on your desktop, or open it from the

Start

menu.

Check the

Run in Demo Mode

check box.

The Demo Mode window appears.

Starting ASDM from a Web Browser

To start ASDM from a web browser, perform the following steps:

Step 1

From a supported web browser on the adaptive security appliance network, enter the following URL:

https://

interface_ip_address

Where

interface_ip_address

is the IP address of ASDM on the adaptive security appliance network.

Note

In transparent firewall mode, enter the management IP address. Be sure to enter

https

, not

http

.

Step 2

Step 3

Step 4

Click

OK

or

Yes

to all browser prompts, including the username and password, which you should leave blank.

The Cisco ASDM 6.3(1) Welcome page displays with the following buttons:

•

Install ASDM Launcher and Run ASDM

•

•

Run ASDM

Run Startup Wizard

Click

Run ASDM

.

Click

OK

or

Yes

to all the browser prompts.

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Multiple ASDM Session Support

Multiple ASDM Session Support

ASDM allows multiple PCs or workstations to each have one browser session open with the same adaptive security appliance software. A single adaptive security appliance can support up to five concurrent ASDM sessions in single, routed mode. Only one session per browser per PC or workstation is supported for a specified adaptive security appliance. In multiple context mode, five concurrent

ASDM sessions are supported per context, up to a maximum of 32 total connections for each adaptive security appliance.

Factory Default Configurations

The factory default configuration is the configuration applied by Cisco to new adaptive security appliances.

For the ASA 5510 and higher adaptive security appliances, the factory default configuration configures an interface for management so you can connect to it using ASDM, with which you can then complete your configuration.

For the ASA 5505 adaptive security appliance, the factory default configuration configures interfaces and NAT so that the adaptive security appliance is ready to use in your network immediately.

The factory default configuration is available only for routed firewall mode and single context mode. See

Chapter 6, “Configuring Multiple Context Mode,”

for more information about multiple context mode.

See Chapter 5, “Configuring the Transparent or Routed Firewall,”

for more information about routed and transparent firewall mode.

Note

In addition to the image files and the (hidden) default configuration, the following folders and files are standard in flash memory: log/, crypto_archive/, and coredumpinfo/coredump.cfg. The date on these files may not match the date of the image files in flash memory. These files aid in potential troubleshooting; they do not indicate that a failure has occurred.


•

•

•

Restoring the Factory Default Configuration, page 2-5

ASA 5505 Default Configuration, page 2-6

ASA 5510 and Higher Default Configuration, page 2-7

Restoring the Factory Default Configuration

This section describes how to restore the factory default configuration.

Limitations

This feature is available only in routed firewall mode; transparent mode does not support IP addresses for interfaces. In addition, this feature is available only in single context mode; an adaptive security appliance with a cleared configuration does not have any defined contexts to configure automatically using this feature.

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2-5



Detailed Steps

Step 1

Step 2

Step 3

Step 4

In the main ASDM application window, choose

File > Reset Device to the Factory Default

Configuration

.

The Reset Device to the Default Configuration dialog box appears.

(Optional) Enter the Management IP address of the management interface, instead of using the default address, 192.168.1.1. For an adaptive security appliance with a dedicated management interface, the interface is called “Management0/0.” For other adaptive security appliance, the configured interface is

Ethernet 1 and called “inside.”

Choose the Management (or Inside) Subnet Mask from the drop-down list.

To save this configuration to internal flash memory, choose

File > Save Running Configuration to

Flash

.

Choosing this option saves the running configuration to the default location for the startup configuration, even if you have previously configured a different location. When the configuration was cleared, this path was also cleared. The next time you reload the adaptive security appliance after restoring the factory configuration, the device boots from the first image in internal flash memory. If an image in internal flash memory does not exist, the adaptive security appliance does not boot.

What to Do Next

See the

“Getting Started With the Configuration” section on page 2-8

to start configuring the adaptive security appliance.

ASA 5505 Default Configuration

The default factory configuration for the ASA 5505 adaptive security appliance configures the following:

•

•

An inside VLAN 1 interface that includes the Ethernet 0/1 through 0/7 switch ports. If you did not set the IP address, then the VLAN 1 IP address and mask are 192.168.1.1 and 255.255.255.0.

An outside VLAN 2 interface that includes the Ethernet 0/0 switch port. VLAN 2 derives its IP address using DHCP.

•

•

•

•

The default route is also derived from DHCP.

All inside IP addresses are translated when accessing the outside using interface PAT.

By default, inside users can access the outside, and outside users are prevented from accessing the inside.

The DHCP server is enabled on the adaptive security appliance, so a PC connecting to the VLAN 1 interface receives an address between 192.168.1.2 and 192.168.1.254.

•

The HTTP server is enabled for ASDM and is accessible to users on the 192.168.1.0 network.

The configuration consists of the following commands: interface Ethernet 0/0 switchport access vlan 2 no shutdown interface Ethernet 0/1


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switchport access vlan 1 no shutdown interface Ethernet 0/2 switchport access vlan 1 no shutdown interface Ethernet 0/3 switchport access vlan 1 no shutdown interface Ethernet 0/4 switchport access vlan 1 no shutdown interface Ethernet 0/5 switchport access vlan 1 no shutdown interface Ethernet 0/6 switchport access vlan 1 no shutdown interface Ethernet 0/7 switchport access vlan 1 no shutdown interface vlan2 nameif outside no shutdown ip address dhcp setroute interface vlan1 nameif inside ip address 192.168.1.1 255.255.255.0

security-level 100 no shutdown object network obj_any subnet 0 0 nat (inside,outside) dynamic interface http server enable http 192.168.1.0 255.255.255.0 inside dhcpd address 192.168.1.2-192.168.1.254 inside dhcpd auto_config outside dhcpd enable inside logging asdm informational


ASA 5510 and Higher Default Configuration

The default factory configuration for the ASA 5510 and higher adaptive security appliance configures the following:

•

The management interface, Management 0/0. If you did not set the IP address, then the IP address and mask are 192.168.1.1 and 255.255.255.0.

•

•

The DHCP server is enabled on the adaptive security appliance, so a PC connecting to the interface receives an address between 192.168.1.2 and 192.168.1.254.

The HTTP server is enabled for ASDM and is accessible to users on the 192.168.1.0 network.

The configuration consists of the following commands: interface management 0/0

ip address 192.168.1.1 255.255.255.0

nameif management

security-level 100 no shutdown asdm logging informational 100 asdm history enable

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2-7


Getting Started With the Configuration

http server enable http 192.168.1.0 255.255.255.0 management dhcpd address 192.168.1.2-192.168.1.254 management dhcpd lease 3600 dhcpd ping_timeout 750 dhcpd enable management

Getting Started With the Configuration

To configure and monitor the adaptive adaptive security appliance, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

For initial configuration using the Startup Wizard, choose

Wizards

>

Startup Wizard

.

To use the IPSec VPN Wizard to configure IPSec VPN connections, choose

Wizards

>

IPSec VPN

Wizard

and complete each screen that appears.

To use the SSL VPN Wizard to configure SSL VPN connections, choose

Wizards

>

SSL VPN Wizard

and complete each screen that appears.

To configure high availability and scalability settings, choose

Wizards

>

High Availability and

Scalability Wizard

. See the

“Configuring Failover with the High Availability and Scalability Wizard” section on page 58-2 for more information.

To use the Packet Capture Wizard to configure packet capture, choose

Wizards

>

Packet Capture

Wizard

.

To display different colors and styles available in the ASDM GUI, choose

View > Office Look and Feel

.

To configure features, click the

Configuration

button on the toolbar and then click one of the feature buttons to display the associated configuration pane.

Note

If the Configuration screen is blank, click

Refresh

on the toolbar to display the screen content.

Step 8

To monitor the adaptive adaptive security appliance, click the

Monitoring

button on the toolbar and then click a feature button to display the associated monitoring pane.

Note

ASDM supports up to a maximum of a 512 KB configuration. If you exceed this amount, you may experience performance issues.

Using the Command Line Interface

This section tells how to enter commands using ASDM, and how to work with the command line interface. This section includes the following topics:

•

•

Using the Command Line Interface Tool, page 2-9

•

•

Handling Command Errors, page 2-9

Using Interactive Commands, page 2-9

Avoiding Conflicts with Other Administrators, page 2-10


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•

Showing Commands Ignored by ASDM on the Device, page 2-10


Using the Command Line Interface Tool

This feature provides a text-based tool for sending commands to the adaptive security appliance and viewing the results.

The commands you can enter with the CLI tool depend on your user privileges. See the “About

Authorization” section on page 31-2

for more information . Review your privilege level in the status bar at the bottom of the main ASDM application window to ensure that you have the required privileges to execute privileged-level CLI commands.

Note

Commands entered via the ASDM CLI tool might function differently from those entered through a terminal connection to the adaptive security appliance.

To use the CLI tool, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6


Tools > Command Line Interface

.

The Command Line Interface dialog box appears.

Choose the type of command (single line or multiple line) that you want, and then choose the command from the drop-down list, or type it in the field provided.

Click

Send

to execute the command.

To enter a new command, click

Clear Response

, and then choose (or type) another command to execute.

Check the

Enable context-sensitive help (?)

check box to provide context-sensitive help for this feature.

Uncheck this check box to disable the context-sensitive help.

After you have closed the Command Line Interface dialog box, if you changed the configuration, click

Refresh

to view the changes in ASDM.

Handling Command Errors

If an error occurs because you entered an incorrect command, the incorrect command is skipped and the remaining commands are processed. A message appears in the Response area to inform you whether or not any error occurred, as well as other related information.

Note

ASDM supports almost all CLI commands. See the

Cisco ASA 5500 Series Command Reference

for a list of commands.

Using Interactive Commands

Interactive commands are not supported in the CLI tool. To use these commands in ASDM, use the

noconfirm

keyword if available, as shown in the following command:

crypto key generate rsa modulus 1024 noconfirm

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2-9



Avoiding Conflicts with Other Administrators

Multiple administrative users can update the running configuration of the adaptive security appliance.

Before using the ASDM CLI tool to make configuration changes, check for other active administrative sessions. If more than one user is configuring the adaptive security appliance at the same time, the most recent changes take effect.

To view other administrative sessions that are currently active on the same adaptive security appliance, choose

Monitoring > Properties > Device Access

.

Showing Commands Ignored by ASDM on the Device

This feature lets you show the list of commands that ASDM does not support. Typically, ASDM ignores them. ASDM does not change or remove these commands from your running configuration. See the

“Unsupported Commands” section on page 1-13

for more information.

To display the list of unsupported commands for ASDM, perform the following steps:

Step 1

Step 2


Tools > Show Commands Ignored by ASDM on

Device

.

Click

OK

when you are done.

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C H A P T E R

3

Using the ASDM User Interface

This chapter describes how to use the ASDM user interface, and includes the following sections:

•

Information About the ASDM User Interface, page 3-1

•

•

•

•

•

•

•

•

•

•

•

•

•

Navigating in the ASDM User Interface, page 3-3

Menus, page 3-4

Toolbar, page 3-10

ASDM Assistant, page 3-10

Status Bar, page 3-11

Device List, page 3-11

Common Buttons, page 3-12

Keyboard Shortcuts, page 3-13

Enabling Extended Screen Reader Support, page 3-14

Organizational Folder, page 3-15

About the Help Window, page 3-15

Home Pane (Single Mode and Context), page 3-16

Home Pane (System), page 3-24

Information About the ASDM User Interface

The ASDM user interface is designed to provide easy access to the many features that the adaptive security appliance supports. The ASDM user interface includes the following elements:

•

A menu bar that provides quick access to files, tools, wizards, and help. Many menu items also have keyboard shortcuts.

•

•

A toolbar that enables you to navigate ASDM. From the toolbar you can access the home, configuration, and monitoring panes. You can also get help and navigate between panes.

A dockable left Navigation pane to move through the Configuration and Monitoring panes. You can click one of the three buttons in the header to maximize or restore this pane, make it a floating pane that you can move, hide it, or close it. To access the Configuration and Monitoring panes, you can do one of the following:


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Chapter 3 Using the ASDM User Interface

Information About the ASDM User Interface

•

•

•

–

Click links on the left side of the application window in the left Navigation pane. The Content pane then displays the path (for example, Configuration > Device Setup > Startup Wizard) in the title bar of the selected pane.

–

If you know the exact path, you can type it directly into the title bar of the Content pane on the right side of the application window, without clicking any links in the left Navigation pane.

A maximize and restore button in the right corner of the Content pane that lets you hide and show the left Navigation pane.

A dockable device list pane with a list of devices that you can access through ASDM. You can click one of the three buttons in the header to maximize or restore this pane, make it a floating pane that

you can move, hide it, or close it. For more information, see the “Device List” section on page 3-11

.

A status bar that shows the time, connection status, user, memory status, running configuration status, privilege level, and SSL status at the bottom of the application window.

•

A left Navigation pane that shows various objects that you can use in the rules tables when you create access rules, NAT rules, AAA rules, filter rules, and service rules. The tab titles within the pane change according to the feature that you are viewing. In addition, the ASDM Assistant appears in this pane.

Figure 3-1 on page 3-2

shows the elements of the ASDM user interface.

Figure 3-1 ASDM User Interface

1 4 3 2

5 6 7 9

3-2


8

OL-20339-01


Navigating in the ASDM User Interface

Legend

7

8

9

2

3

4

5

6

GUI Element Description

1 Menu Bar

Search Field

Toolbar

Navigation Path

Device List Pane

Left Navigation Pane

Content Pane

Right Navigation Pane

Status Bar

Note

Tool tips have been added for various parts of the GUI, including Wizards, the Configuration and

Monitoring panes, and the Status Bar. To view tool tips, hover your mouse over a specific user interface element, such as an icon in the status bar.

Navigating in the ASDM User Interface

To move efficiently throughout the ASDM user interface, you may use a combination of menus, the toolbar, dockable panes, and the left and right Navigation panes, which are described in the previous section. The available functions appear in a list of buttons below the Device List pane. An example list could include the following function buttons:

•

•

•

•

•

•

Device Setup

Firewall

Trend Micro Content Security


Remote Access VPN

Site to Site VPN

•

Device Management

The list of function buttons that appears is based on the licensed features that you have purchased. Click each button to access the first pane in the selected function for either the Configuration view or the

Monitoring view. The function buttons are not available in the Home view.

To change the display of function buttons, perform the following steps:

Step 1

Step 2

Choose the drop-down list below the last function button to display a context menu.

Choose one of the following options:

•

•

To show more buttons, click

Show More Buttons

.

To show fewer buttons, click

Show Fewer Buttons

.

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3-3


Menus

Step 3

•

•

To add or remove buttons, click

Add or Remove Buttons

, then click the button to add or remove from the list that appears.

To change the sequence of the buttons, choose

Option

to display the Option dialog box, which displays a list of the buttons in their current order. Then choose one of the following:

–

To move up a button in the list, click

Move Up

.

–

–

To move down a button in the list, click

Move Down

.

To return the order of the items in the list to the default setting, click

Reset

.

To save your settings and close this dialog box, click

OK

.

Menus

You can access ASDM menus using the mouse or keyboard. For information about accessing the menu

bar from the keyboard, see the “Keyboard Shortcuts” section on page 3-13

.

ASDM has the following menus:

•

•

•

•

•

•

File Menu, page 3-4

View Menu, page 3-5

Tools Menu, page 3-6

Wizards Menu, page 3-8

Window Menu, page 3-9

Help Menu

File Menu

The File menu lets you manage adaptive security appliance configurations. The following table lists the tasks that you can perform using the File menu.

File Menu Item

Refresh ASDM with the Running

Configuration on the Device

Refresh

Description

Loads a copy of the running configuration into ASDM.

Reset Device to the Factory Default

Configuration

Ensures that ASDM has a current copy of the running configuration.

Restores the configuration to the factory default. See the

“Restoring the Factory Default Configuration” section on page 2-5


Displays the current running configuration in a new window.

Show Running Configuration in

New Window

Save Running Configuration to

Flash

Writes a copy of the running configuration to flash memory.

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Menus

File Menu Item


TFTP Server


Standby Unit

Sends a copy of the running configuration file on the primary unit to the running configuration of a failover standby unit.

Save Internal Log Buffer to Flash Saves the internal log buffer to flash memory.

Print

Clear ASDM Cache

Prints the current page. We recommend landscape page orientation when you print rules. When you use Internet Explorer, permission to print was already granted when you originally accepted the signed applet.

Removes local ASDM images. ASDM downloads images locally when you connect to ASDM.

Clear ASDM Password Cache

Description

Stores a copy of the current running configuration file on a TFTP server. See the

“Saving the Running Configuration to a TFTP

Server” section on page 75-6 for more information.


Exit

Removes the password cache if you have defined a new password and still have a existing password that is different than the new password.

Empties the syslog message buffer.

Closes ASDM.

View Menu

The View menu lets you display various parts of the ASDM user interface. Certain items are dependent on the current view. You cannot select items that cannot be displayed in the current view. The following table lists the tasks that you can perform using the View menu.

View Menu Item

Home

Configuration

Monitoring

Device List

Navigation

ASDM Assistant

SIP Details

Latest ASDM Syslog Messages

Description

Displays the Home view.

Displays the Configuration view.

Displays the Monitoring view.

Display a list of devices in a dockable pane. See the

“Device List” section on page 3-11 for more information.

Shows and hides the display of the Navigation pane in the

Configuration and Monitoring views.

Searches and finds useful ASDM procedural help about certain tasks. See the

“ASDM Assistant” section on page 3-10


Shows and hides voice network information.

Shows and hides the display of the Latest ASDM Syslog

Messages pane in the Home view. This pane is only available in the Home view. If you do not have sufficient memory to upgrade to the most current release, syslog message %ASA-1-211004 is generated, indicating what the installed memory is and what the required memory is. This message reappears every 24 hours until the memory is upgraded.

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Menus

View Menu Item

Addresses

Services

Time Ranges

Global Pools

Find in ASDM

Back

Forward

Reset Layout

Office Look and Feel

Description

Shows and hides the display of the Addresses pane. The

Addresses pane is only available for the Access Rules, NAT

Rules, Service Policy Rules, AAA Rules, and Filter Rules panes in the Configuration view.

Shows and hides the display of the Services pane. The Services pane is only available for the Access Rules, NAT Rules, Service

Policy Rules, AAA Rules, and Filter Rules panes in the

Configuration view.

Shows and hides the display of the Time Ranges pane. The Time

Ranges pane is only available for the Access Rules, Service

Policy Rules, AAA Rules, and Filter Rules panes in the

Configuration view.

Shows and hides the display of the Global Pools pane. The Global

Pools pane is only available for the NAT Rules pane in the

Configuration view.

Locates an item for which you are searching, such as a feature or the ASDM Assistant.

Returns to the previous pane. See the

“Common Buttons” section on page 3-12 for more information.

Goes to the next pane previously visited. See the

“Common

Buttons” section on page 3-12 for more information.

Returns the layout to the default configuration.

Changes the screen fonts and colors to the Microsoft Office settings.

Tools Menu

The Tools menu provides you with the following series of tools to use in ASDM.

Tools Menu Item

Command Line Interface

Show Commands Ignored by

ASDM on Device

Packet Tracer

Description

Sends commands to the adaptive security appliance and view the results. See the

“Getting Started With the Configuration” section on page 2-8 for more information.

Displays unsupported commands that have been ignored by

ASDM. See the

“Showing Commands Ignored by ASDM on the

Device” section on page 2-10


Traces a packet from a specified source address and interface to a destination. You can specify the protocol and port of any type of data and view the lifespan of a packet, with detailed information about actions taken on it. See the

“Tracing Packets with Packet Tracer” section on page 76-7 for more information.

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Menus

Tools Menu Item

Ping

Traceroute

File Management

Upgrade Software from Local

Computer

Check for ASA/ASDM Updates

Description

Verifies the configuration and operation of the adaptive security appliance and surrounding communications links, as well as performs basic testing of other network devices. See the

“Verifying ASA Configuration and Operation, and Testing

Interfaces Using Ping” section on page 76-3 for more

information.

Determines the route that packets will take to their destination.

See the

“Determining Packet Routing with Traceroute” section on page 76-6 for more information.

Views, moves, copies, and deletes files stored in flash memory.

You can also create a directory in flash memory. See the

“Managing Files” section on page 75-1 for more information.

You can also transfer files between various file systems, including

TFTP, flash memory, and your local PC. See the “Transferring

Files” section on page 75-5


Uploads a adaptive security appliance image, ASDM image, or another image on your PC to flash memory. See the

“Upgrading

Software from Your Local Computer” section on page 75-10

dialog box for more information.

Upgrades adaptive security appliance software and ASDM software through a wizard. See the

“Upgrading Software from the

Cisco.com Wizard” section on page 75-11


Backup Configurations

Restore Configurations

System Reload

Backs up the adaptive security appliance configuration, a Cisco

Secure Desktop image, and SSL VPN Client images and profiles.

See the

“Backing Up Configurations” section on page 75-13


Restores the adaptive security appliance configuration, a Cisco

Secure Desktop image, and SSL VPN Client images and profiles.

See the

“Restoring Configurations” section on page 75-17


Restarts the ASDM and reload the saved configuration into memory. See the

“Scheduling a System Restart” section on page 75-12


Administrator’s Alerts to Clientless

SSL VPN Users

Enable an administrator to send an alert message to clientless

SSL VPN users. See the

“Sending an Administrator’s Alert to

Clientless SSL VPN Users” section on page 76-12


Preferences

ASDM Java Console

Changes the behavior of specified ASDM functions between sessions. See the

“Defining ASDM Preferences” section on page 9-11


Shows the Java console. See the

“Viewing and Copying Logged

Entries with the ASDM Java Console” section on page 76-12


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Menus

Wizards Menu

The Wizards menu lets you run a wizard to configure multiple features. The following table lists the available Wizards and their features.

Wizards Menu Item

Startup Wizard

IPSec VPN Wizard

SSL VPN Wizard

High Availability and Scalability

Wizard

Unified Communication Wizard

Packet Capture Wizard

Description

Guides you, step-by-step, through the initial configuration of the adaptive security appliance. For more information, see

Using the

Startup Wizard

.

Enables you to configure an IPSec VPN policy on the adaptive

security appliance. For more information, see the IPSec VPN

Wizard .

Enables you to configure an SSL VPN policy on the adaptive security appliance. For more information, see the SSL

VPN

Wizard .

Allows you to configure failover and VPN cluster load balancing on the adaptive security appliance. For more information, see

Accessing the High Availability and Scalability Wizard .

Enables you to configure unified communication features, such as an IP phone, on the adaptive security appliance. For more information, see the

Using the Cisco Unified Communication

Wizard .

Allows you to configure packet capture on the adaptive security appliance. The wizard runs one packet capture on each ingress and egress interface. After you run the capture, you can save it on your computer, and then examine and analyze the capture with a packet analyzer. For more information, see the

“Configuring and

Running Captures with the Packet Capture Wizard” section on page 76-8 .

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Menus

Window Menu

The Window menu enables you to move between ASDM windows. The active window appears as the selected window.

Help Menu

The Help menu provides links to online Help, as well as information about ASDM and the adaptive security appliance. The following table lists the tasks that you can perform using the Help menu.

Help Menu Items

Help Topics

Help for Current Screen

Release Notes

ASDM Assistant

About Cisco Adaptive

Security Appliance (ASA)

About Cisco ASDM 6.3

Description

Opens a new browser window with help organized by contents, window name, and indexed in the left frame. Use these methods to find help for any topic, or search using the Search tab.

Opens context-sensitive help about that screen. The wizard runs the screen, pane, or dialog box that is currently open. Alternatively, you can also click the question mark (

?

) help icon.

Opens the most current version of the

Release Notes for Cisco ASDM

on Cisco.com. The release notes contain the most current information about ASDM software and hardware requirements, and the most current information about changes in the software.

Opens the ASDM Assistant, which lets you search downloadable content from Cisco.com, with details about performing certain tasks.

Displays information about the adaptive security appliance, including the software version, hardware set, configuration file loaded at startup, and software image loaded at startup. This information is helpful in troubleshooting.

Displays information about ASDM such as the software version, hostname, privilege level, operating system, device type, and Java version.

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Toolbar

Toolbar

The Toolbar below the menus provides access to the Home view, Configuration view, and Monitoring view. It also lets you choose between the system and security contexts in multiple context mode, and provides navigation and other commonly used features. The following table lists the tasks that you can perform using the Toolbar.

Toolbar Button

System/Contexts

Home

Configuration

Monitoring

Back

Forward

Search

Refresh

Save

Help

Description

Shows which context you are in. To open the context list in the left-hand pane, click the down arrow, then click the up arrow to restore the context drop-down list. After you have expanded this list, click the left arrow to collapse the pane, then the right arrow to restore the pane. To manage the system, choose

System

from the drop-down list. To manage the context, choose one from the drop-down list.

Displays the Home pane, which lets you view important information about your adaptive security appliance such as the status of your interfaces, the version you are running, licensing information, and performance. See the

“Home Pane (Single Mode and Context)” section on page 3-16 for more

information. In multiple mode, the system does not have a Home pane.

Configures the adaptive security appliance. Click a function button in the left

Navigation pane to configure that function.

Monitors the adaptive security appliance. Click a function button in the left

Navigation pane to configure that function.

Returns to the last pane of ASDM that you visited.

Goes forward to the last pane of ASDM that you visited.

Searches for a feature in ASDM. The Search function looks through the titles of each pane and presents you with a list of matches, and gives you a hyperlink directly to that pane. If you need to switch quickly between two different panes that you found, click

Back

or

Forward

. See the

“ASDM

Assistant” section on page 3-10


Refreshes ASDM with the current running configuration, except for graphs in any of the Monitoring panes.

Saves the running configuration to the startup configuration for write-accessible contexts only.

Shows context-sensitive help for the screen that is currently open.

ASDM Assistant

The ASDM Assistant lets you search and view useful ASDM procedural help about certain tasks. This feature is available in routed and transparent modes, and in the single and system contexts.

To access information, choose

View > ASDM Assistant > How Do I?

or enter a search request from the

Look For field in the menu bar. From the Find drop-down list, choose

How Do I?

to begin the search.

To use the ASDM Assistant, perform the following steps:

Step 1


View > ASDM Assistant

.


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Step 2

Step 3

The ASDM Assistant pane appears.

In the Search field, enter the information that you want to find, and click

Go

.

The requested information appears in the Search Results pane.

Click any links that appear in the Search Results and Features areas to obtain more details.

Status Bar

Status Bar

The status bar appears at the bottom of the ASDM window. The following table lists the areas shown from left to right.

Area

Status

Description

The status of the configuration (for example, “Device configuration loaded successfully.”)

The status of the failover unit, either active or standby.

Failover

User Name

User Privilege

Commands Ignored by

ASDM

The username of the ASDM user. If you logged in without a username, the username is “admin.”

The privilege of the ASDM user.

Click the icon to show a list of commands from your configuration that ASDM did not process. These commands will not be removed from the configuration.

Connection to Device The ASDM connection status to the adaptive security appliance. See the

“Connection to Device” section on page 3-11


Syslog Connection The syslog connection is up, and the adaptive security appliance is being monitored.

SSL Secure

Time

The connection to ASDM is secure because it uses SSL.

The time that is set on the adaptive security appliance.

Connection to Device

ASDM maintains a constant connection to the adaptive security appliance to maintain up-to-date

Monitoring and Home pane data. This dialog box shows the status of the connection. When you make a configuration change, ASDM opens a second connection for the duration of the configuration, and then closes it; however, this dialog box does not represent the second connection.

Device List

The device list is a dockable pane. You can click one of the three buttons in the header to maximize or restore this pane, make it a floating pane that you can move, hide it, or close it. This pane is available in the Home, Configuration, Monitoring, and System views. You can use this pane to switch to another

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Common Buttons

device; however, that device must run the same version of ASDM that you are currently running. To display the pane fully, you must have at least two devices listed. This feature is available in routed and transparent modes, and in the single, multiple, and system contexts.

To use this pane to connect to another device, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Click

Add

to add another device to the list.

The Add Device dialog box appears.

In the Device/IP Address/Name field, type the device name or IP address of the device, and then click

OK

.

Click

Delete

to remove a selected device from the list.

Click

Connect

to connect to another device.

The Enter Network Password dialog box appears.

Type your username and password in the applicable fields, and then click

Login

.

Common Buttons

Many ASDM panes include buttons that are listed in the following table. Click the applicable button to complete the desired task:

Button

Apply

Save

Reset

Restore Default

Cancel

Enable

Close

Clear

Back

Forward

Help

Description

Sends changes made in ASDM to the adaptive security appliance and applies them to the running configuration.

Writes a copy of the running configuration to flash memory.

Discards changes and reverts to the information displayed before changes were made or the last time that you clicked Refresh or Apply. After you click

Reset

, click

Refresh

to make sure that information from the current running configuration appears.

Clears the selected settings and returns to the default settings.

Discards changes and returns to the previous pane.

Displays read-only statistics for a feature.

Closes an open dialog box.

Remove information from a field, or remove a check from a check box.

Returns to the previous pane.

Goes to the next pane.

Displays help for the selected pane or dialog box.

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Keyboard Shortcuts

Keyboard Shortcuts

You can use the keyboard to navigate the ASDM user interface.

Table 3-1

lists the keyboard shortcuts you can use to move across the three main areas of the ASDM user interface.

Table 3-1 Keyboard Shortcuts Within the Main Window

To display the

Home Pane

Configuration Pane

Monitoring Pane

Help

Back

Forward

Refresh the display

Cut

Copy

Windows/Linux

Ctrl+H

Ctrl+G

Ctrl+M

F1

Alt+Left Arrow

Alt+Rightarrow

F5

Ctrl+X

Ctrl+C

Paste

Save the configuration

Popup menus

Close a secondary window

Ctrl+V

Ctrl+S

Shift+F10

Alt+F4

Find Ctrl+F

Exit Alt+F4

Exit a table or text area Ctrl_Shift or

Ctrl+Shift+Tab

MacOS

Shift+Command+H

Shift+Command+G

Shift+Command+M

Command+?

Command+[

Command+]

Command+R

Command+X

Command+C

Command+V

Command+S

—

Command+W

Command+F

Command+Q

Ctril+Shift or

Ctrl+Shift+Tab

Table 3-2

lists the keyboard shortcut you can use to navigate within a pane.

Table 3-2 Keyboard Shortcuts Within a Pane

To move the focus to the

Next field

Previous field

Next field when the focus is in a table

Previous field when the focus is in a table

Next tab (when a tab has the focus)

Previous tab (when a tab has the focus)

Next cell in a table

Previous sell in a table

Next pane (when multiple panes are displayed)

Previous pane (when multiple panes are displayed)

Press

Tab

Shift+Tab

Ctrl+Tab

Shift+Ctrl+Tab

Right Arrow

Left Arrow

Tab

Shift+Tab

F6

Shift+F6


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Enabling Extended Screen Reader Support

Table 3-3 lists the keyboard shortcuts you can use with the Log Viewers.

Table 3-3 Keyboard Shortcuts for the Log Viewer

To Windows/Linux

Pause and Resume Real-Time Log Viewer Ctrl+U

Refresh Log Buffer Pane


Copy Selected Log Entry

Save Log

F5

Ctrl+Delete

Ctrl+C

Ctrl+S

Print

Close a secondary window

Ctrl+P

Alt+F4

MacOS

Command+

Command+R

Command+Delete

Command+C

Command+S

Command+P

Command+W

Table 3-4 lists the keyboard shortcuts you can use to access menu items.

Table 3-4 Keyboard Shortcuts to Access Menu Items

To access the

Menu Bar

Next Menu

Previous Menu

Next Menu Option

Previous Menu Option

Selected Menu Option

Windows/Linux

Alt

Right Arrow

Left Arrow

Down Arrow

Up Arrow

Enter

Enabling Extended Screen Reader Support

By default, labels and descriptions are not included in tab order when you press the Tab key to navigate a pane. Some screen readers, such as JAWS, only read screen objects that have the focus. You can include the labels and descriptions in the tab order by enabling extended screen reader support.

To enable extended screen reader support, perform the following steps:

Step 1

Step 2

Step 3

Step 4


Tools > Preferences

.

The Preferences dialog box appears.

On the General tab, check the

Enable screen reader support

check box.

Click

OK

.

Restart ASDM to activate screen reader support.

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Organizational Folder

Organizational Folder

Some folders in the navigation pane for the configuration and monitoring views do not have associated configuration or monitoring panes. These folders are used to organize related configuration and monitoring tasks. Clicking these folders displays a list of sub-items in the right Navigation pane. You can click the name of a sub-item to go to that item.

About the Help Window


•

Header Buttons, page 3-15

•

Browser Window, page 3-15

Header Buttons

To obtain the information that you need, click the applicable button listed in the following table.

Button

About ASDM

Search

Using Help

Glossary

Contents

Screens

Index

Description

Displays information about ASDM, including the hostname, version number, device type, adaptive security appliance software version number, privilege level, username, and operating system being used.

Searches for information among online help topics.

Describes the most efficient methods for using online help.

Lists terms found in ASDM and adaptive security appliances.

Displays a table of contents.

Lists help files by screen name.

Displays an index of help topics found in ASDM online help.

Browser Window

When you open help and a help page is already open, the new help page will appear in the same browser window. If no help page is open, then the help page will appear in a new browser window.

When you open help and Netscape Communicator is the default browser, the help page will appear in a new browser window. If Internet Explorer is the default browser, the help page may appear either in the last-visited browser window or in a new browser window, according to your browser settings. You can control this behavior in Internet Explorer by choosing

Tools > Internet Options > Advanced > Reuse windows for launching shortcuts

.

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Home Pane (Single Mode and Context)


The ASDM Home pane lets you view important information about your adaptive security appliance.

Status information in the home pane is updated every ten seconds. This pane usually has two tabs: Device

Dashboard and Firewall Dashboard.

If you have a CSC SSM installed in your adaptive security appliance, the Content Security tab also appears in the Home pane. The additional tab displays status information about the CSC SSM software.

If you have IPS software installed in your adaptive security appliance, the Intrusion Prevention tab also appears in the Home pane. The additional tab displays status information about the IPS software.


•

•

•

•

Device Dashboard Tab, page 3-16

Firewall Dashboard Tab, page 3-19

Content Security Tab, page 3-21

Intrusion Prevention Tab, page 3-22

Device Dashboard Tab

The Device Dashboard tab lets you view, at a glance, important information about your adaptive security appliance, such as the status of your interfaces, the version you are running, licensing information, and performance.

Figure 3-2

shows the elements of the Device Dashboard tab.

Figure 3-2 Device Dashboard Tab

1

3

5

2

4

6

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Legend

2

3

4


1

Device Information Pane, page 3-17

Interface Status Pane, page 3-17

VPN Sessions Pane, page 3-17

Traffic Status Pane, page 3-18

5

6

See

Figure 3-3

System Resources Status Pane, page 3-18

Traffic Status Pane, page 3-18

Latest ASDM Syslog Messages Pane, page 3-18

Device Information Pane

The Device Information pane includes two tabs that show device information:

•

•

General Tab, page 3-17

License Tab, page 3-17

General Tab

This tab shows basic information about the adaptive security appliance, including the hostname, software version, and RAM.

Note

If you do not have enough memory to upgrade to the most current release of the adaptive security appliance, the Memory Insufficient Warning dialog box appears. Follow the directions that appear in this dialog box to continue using the adaptive security appliance and ASDM in a supported manner. Click

OK

to close this dialog box.

License Tab

This tab shows a subset of licensed features. To view detailed license information, or to enter a new activation key, click

More Licenses

; the Configuration > Device Management > Licensing > Activation

Key pane appears. See Chapter 4, “Managing Feature Licenses.”

Interface Status Pane

This pane shows the status of each interface. If you select an interface row, the input and output throughput in Kbps displays below the table.

VPN Sessions Pane

This pane shows the VPN tunnel status. Click

Details

to go to the Monitoring > VPN > VPN Statistics

> Sessions pane.

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Failover Status Pane

This pane shows the failover status.

Click

Configure

to start the High Availability and Scalability Wizard. After you have completed the wizard, the failover configuration status (either Active/Active or Active/Standby) appears.

If failover is configured, click

Details

to open the Monitoring > Properties > Failover > Status pane.

System Resources Status Pane

This pane shows CPU and memory usage statistics.

Traffic Status Pane

This pane shows graphs for connections per second for all interfaces and for the traffic throughput of the lowest security interface.

Latest ASDM Syslog Messages Pane

This pane shows the most recent system messages generated by the adaptive security appliance, up to a maximum of 100 messages. If logging is disabled, click

Enable Logging

to enable logging.

Figure 3-3

shows the elements of the Latest ASDM Syslog Messages pane.

Figure 3-3 Latest ASDM Syslog Messages Pane

1

2

3

4

5

6

7

8

Legend

2

3


1 To resize the pane, drag the divider up or down.

4

5

Expands the pane. To return the pane to the default size, click the double-square icon.

Makes a floating pane. To dock the pane, click the docked pane icon.

Enables or disables Auto-hide. When Auto-hide is enabled, move your cursor over the

Latest ASDM Syslog Messages button in the left, bottom corner and the pane displays.

Move your cursor away from the pane, and it disappears.

Closes the pane. To show the pane, choose

View Latest ASDM Syslog Messages.

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6 To continue updating the display of syslog messages, click the green icon on the right-hand side.

7

8

To stop updating the display of syslog messages, click the red icon on the right-hand side.

To open the Logging Filters pane, click the filters icon on the right-hand side.

•

•

•

•

To clear the current messages, right-click an event and click

Clear Content

.

To save the current messages to a file on your PC, right-click an event and click

Save Content

.

To copy the current content, right-click an event and click

Copy

.

To change the background and foreground colors of syslog messages according to their severity, right-click an event and click

Color Settings

.

Firewall Dashboard Tab

The Firewall Dashboard tab lets you view important information about the traffic passing through your adaptive security appliance. This dashboard differs depending on whether you are in single context mode or multiple context mode. In multiple context mode, the Firewall Dashboard is viewable within each context.

Figure 3-4 shows some of the elements of the Firewall Dashboard tab.

Figure 3-4 Firewall Dashboard Tab

1

2

3

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3-19



Legend


1

Traffic Overview Pane, page 3-20

2

Top 10 Access Rules Pane, page 3-20

3

Top Usage Status Pane, page 3-20

(not shown)

Top Ten Protected Servers Under SYN Attack Pane, page 3-21

(not shown)

Top 200 Hosts Pane, page 3-21

(not shown)

Top Botnet Traffic Filter Hits Pane, page 3-21

Traffic Overview Pane

Enabled by default. If you disable basic threat detection (see the

“Configuring Basic Threat Detection

Statistics” section on page 51-4

), then this area includes an Enable button that lets you enable basic threat detection. The runtime statistics include the following information, which is

display-only

:

•

•

The number of connections and NAT translations.

The rate of dropped packets per second caused by access list denials and application inspections.

•

The rate of dropped packets per second that are identified as part of a scanning attack, or that are incomplete sessions detected, such as TCP SYN attack detected or no data UDP session attack detected.

Top 10 Access Rules Pane

Enabled by default. If you disable threat detection statistics for access rules (see the

“Configuring

Advanced Threat Detection Statistics” section on page 51-5 ), then this area includes an Enable button

that lets you enable statistics for access rules.

In the Table view, you can select a rule in the list and right-click the rule to display a popup menu item,

Show Rule

. Choose this item to go to the Access Rules table and select that rule in this table.

Top Usage Status Pane

Disabled by default. This area includes Enable buttons that let you enable the features, or you can enable them according to the

“Configuring Basic Threat Detection Statistics” section on page 51-4 . The Top 10

Services Enable button enables statistics for both ports and protocols (both must be enabled for the display). The Top 10 Sources and Top 10 Destinations Enable buttons enable statistics for hosts. The top usage status statistics for hosts (sources and destinations), and ports and protocols are displayed.

Caution

Enabling statistics can affect the adaptive security appliance performance, depending on the type of statistics enabled. Enabling statistics for hosts affects performance in a significant way; if you have a high traffic load, you might consider enabling this type of statistics temporarily. Enabling statistics for ports, however, has a modest effect.

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Top Ten Protected Servers Under SYN Attack Pane

Disabled by default. This area includes an Enable button that lets you enable the feature, or you can

enable it according to the “Configuring Basic Threat Detection Statistics” section on page 51-4

.

Statistics for the top ten protected servers under attack are displayed.

For the average rate of attack, the adaptive security appliance samples the data every 30 seconds over the rate interval (by default 30 minutes).

If there is more than one attacker, then “<various>” displays, followed by the last attacker IP address.

Click

Detail

to view statistics for all servers (up to 1000) instead of just 10 servers. You can also view history sampling data. The adaptive security appliance samples the number of attacks 60 times during the rate interval, so for the default 30-minute period, statistics are collected every 60 seconds.

Top 200 Hosts Pane

Disabled by default. Shows the top 200 hosts connected through the adaptive security appliance. Each entry of a host contains the IP address of the host and the number of connections initiated by the host, and is updated every 120 seconds. To enable this display, enter the

hpm topnenable

command.

Top Botnet Traffic Filter Hits Pane

Disabled by default. This area includes links to configure the Botnet Traffic Filter. Reports of the top ten botnet sites, ports, and infected hosts provide a snapshot of the data, and may not match the top ten items since statistics started to be collected. If you right-click an IP address, you can invoke the whois tool to learn more about the botnet site.

For more information, see

Configuring the Botnet Traffic Filter

.

Content Security Tab

The Content Security tab lets you view important information about the Content Security and Control

(CSC) SSM. This pane appears only if CSC software running on the CSC SSM is installed in the adaptive security appliance.

For an introduction to the CSC SSM, see

Information About the CSC SSM .

Note

If you have not completed the CSC Setup Wizard by choosing

Configuration > Trend Micro Content

Security > CSC Setup

, you cannot access the panes under Home > Content Security. Instead, a dialog box appears and lets you access the CSC Setup Wizard directly from this location.

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Figure 3-5

shows the elements of the Content Security tab.

Figure 3-5 Content Security Tab


1

3

2

4

5

Legend

3

4

5


1 CSC SSM Information pane.

2 Threat Summary pane. Shows aggregated data about threats detected by the CSC SSM, including the following threat types: Virus, Spyware, URL Filtered or Blocked, Spam.

Blocked, Files Blocked, and Damage Control Services.

System Resources Status pane.

Email Scan pane. The graphs display data in ten-second intervals.

Latest CSC Security Events pane.

Intrusion Prevention Tab

The Intrusion Prevention tab lets you view important information about IPS. This tab appears only when you have IPS software running on the AIP SSM that is installed on the adaptive security appliance.

To connect to the IPS software on the AIP SSM, perform the following steps:

Step 1

Step 2

In the main ASDM application window, click the

Intrusion Prevention

tab.

In the Connecting to IPS dialog box, choose one of the following options:

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Step 3

Step 4

•

Management IP Address, which connects to the IP address of the management port on the SSM.

•

Other IP Address or Hostname, which connects to an alternate IP address or hostname on the SSM.

Enter the port number in the Port field, and then click

Continue

.

In the Enter Network Password dialog box, type your username and password in the applicable fields, and then click

Login

.

For more information about intrusion prevention, see

Configuring the IPS Application on the

AIP SSM and SSC

.

Figure 3-6 shows the elements of the Health Dashboard tab, located on the Intrusion Prevention tab.

Figure 3-6 Intrusion Prevention Tab (Health Dashboard)

1 3 4 2 5

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Legend

2

3

4

5


1 Sensor Information pane.

Sensor Health pane.

CPU, Memory, and Load pane.

Interface Status pane.

Licensing pane.


3-23


Home Pane (System)

Home Pane (System)

The ASDM System Home pane lets you view important status information about your adaptive security appliance. Many of the details available in the ASDM System Home pane are available elsewhere in

ASDM, but this pane shows at-a-glance how your adaptive security appliance is running. Status information in the System Home pane is updated every ten seconds.


shows the elements of the System Home pane.

Figure 3-7 System Home Pane

2

3

1

5

4

Legend

3

4

5


1 System vs. Context selection.

2 Interface Status pane. Choose an interface to view the total amount of traffic through the interface.

Connection Status pane.

CPU Status pane.

Memory Status pane.

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C H A P T E R

4

Managing Feature Licenses

A license specifies the options that are enabled on a given adaptive security appliance. This document describes how to obtain a license activation key and how to activate it. It also describes the available licenses for each model.

Note

This chapter describes licensing for Version 8.3; for other versions, see the licensing documentation that applies to your version: http://www.cisco.com/en/US/products/ps6120/products_licensing_information_listing.html


•

Supported Feature Licenses Per Model, page 4-1

•

•

•

•

•

•

•

Information About Feature Licenses, page 4-11

Guidelines and Limitations, page 4-21

Viewing Your Current License, page 4-23

Obtaining an Activation Key, page 4-23

Activating or Deactivating Keys, page 4-24

Configuring a Shared License, page 4-25

Feature History for Licensing, page 4-27

Supported Feature Licenses Per Model

This section describes the licenses available for each model as well as important notes about licenses.


•

Licenses Per Model, page 4-2

•

•

License Notes, page 4-9

VPN License and Feature Compatibility, page 4-11


4-1 OL-20339-01

Chapter 4 Managing Feature Licenses


Licenses Per Model

This section lists the feature licenses available for each model:

•

ASA 5505,

Table 4-1 on page 4-3

•

•

•

•

ASA 5510,

ASA 5520,


ASA 5540,



ASA 5550,


•

ASA 5580,


Items that are in italics are separate, optional licenses with which that you can replace the Base or

Security Plus license. You can mix and match licenses, for example, the 10 security context license plus the Strong Encryption license; or the 500 Clientless SSL VPN license plus the GTP/GPRS license; or all four licenses together.

4-2


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Table 4-1

shows the licenses for the ASA 5505.

ASA 5505 Adaptive Security Appliance License Features Table 4-1

ASA 5505

Firewall Licenses


1

Firewall Conns, Concurrent 10 K

GTP/GPRS

Intercompany Media

Engine

1

Unified Comm. Sessions

1

VPN Licenses

2

Adv. Endpoint Assessment Disabled


1

Disabled

AnyConnect Mobile

1

Disabled

AnyConnect Premium SSL

VPN Edition (sessions)

1

Base License

Disabled

No support

Disabled

2

2

Optional Time-based license:

Available

Optional license: Available

Optional license: 24




Optional Permanent or Time-based licenses:

Security Plus

Disabled

25 K

No support

Disabled

2


Available


Optional license: 24

Disabled

Disabled



Disabled

2



10

10 (max. 25 combined IPSec and SSL VPN)

No support

25 10


No support

25

IPSec VPN (sessions)

1

VPN Load Balancing

1

General Licenses

Encryption

Failover

Security Contexts

Users, concurrent

3

VLANs/Zones, Maximum

VLAN Trunk, Maximum

Base (DES)

No support

50 Unlimited

3 (2 regular zones and 1 restricted zone)

No support

Opt. lic.: Strong (3DES/AES)

No support

10

4

Optional licenses:

Base (DES)

Active/Standby (no stateful failover)

No support

10

4



20

8 trunks

50 Unlimited

1.

See the

“License Notes” section on page 4-9 .

2.

See the

“VPN License and Feature Compatibility” section on page 4-11 .

3.

In routed mode, hosts on the inside (Business and Home VLANs) count towards the limit only when they communicate with the outside (Internet VLAN).

Internet hosts are not counted towards the limit. Hosts that initiate traffic between Business and Home are also not counted towards the limit. The interface associated with the default route is considered to be the Internet interface. If there is no default route, hosts on all interfaces are counted toward the limit.

In transparent mode, the interface with the lowest number of hosts is counted towards the host limit. See the

show local-host

command to view host limits.

4.

For a 10-user license, the max. DHCP clients is 32. For 50 users, the max. is 128. For unlimited users, the max. is 250, which is the max. for other models.

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4-3



Table 4-2 shows the licenses for the ASA 5510.


ASA 5510



1

Base License Security Plus

Disabled


Available

Disabled


Available


GTP/GPRS

Intercompany Media

Engine

1

Unified Comm. Sessions

1

VPN Licenses

2



1

AnyConnect Mobile

1

Disabled

Disabled



2


VPN Load Balancing


Encryption

Failover

Interface Speed

1

1

No support

Disabled

2


24 50 100


10 25 50 100 250

Optional Shared licenses: Participant or

Server. For the Server, these licenses are available:

1

500-50,000 in increments of 500

50,000-545,000 in increments of 1000

Optional Shared licenses: Participant or

Server. For the Server, these licenses are available:

1

500-50,000 in increments of 500

50,000-545,000 in increments of 1000

250 (max. 250 combined IPSec and SSL VPN) 250 (max. 250 combined IPSec and SSL VPN)

No support Supported

Base (DES)

No support






All: Fast Ethernet

130 K

No support

Disabled

2


24

Disabled

Disabled

Disabled

2





10 25 50 100 250

Base (DES)


50 100


Active/Standby or Active/Active

1

Ethernet 0/0 and 0/1: Gigabit Ethernet

3

Security Contexts

VLANs, Maximum

No support

50

Ethernet 0/2, 0/3, and 0/4 (and any others):

Fast Ethernet

2


5

100

1.

See the

“License Notes” section on page 4-9

.

2.

See the

“VPN License and Feature Compatibility” section on page 4-11

.

3.

Although the Ethernet 0/0 and 0/1 ports are Gigabit Ethernet, they are still identified as “Ethernet” in the software.

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Table 4-3



ASA 5520



1

Base License

Disabled


GTP/GPRS

Intercompany Media

Engine

1

Disabled

Disabled

Unified Communications

Proxy Sessions

1

2

VPN Licenses

2



1

AnyConnect Mobile

1

Disabled

Disabled


24 50 100 250 500




750 1000



2


10 25 50 100 250 500 750

Optional Shared licenses: Participant or Server. For the Server, these licenses are available:

1

500-50,000 in increments of 500 50,000-545,000 in increments of 1000


1

VPN Load Balancing

1



Supported

Encryption

Failover

Security Contexts

VLANs, Maximum

Base (DES)

Optional Time-based license: Available




2

150

Optional license: Strong (3DES/AES)


5 10 20

1

1.

See the


2.

See the


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4-5





ASA 5540 Base License



1

Disabled


GTP/GPRS

Intercompany Media

Engine

1

Disabled

Disabled





Proxy Sessions

1

2

VPN Licenses

2



1

Disabled

AnyConnect Mobile

1

Disabled


24 50 100 250 500






750 1000 2000

2


10 25 50 100 250 500 750 1000 2500


1



Supported


1

VPN Load Balancing

1


Encryption

Failover

Security Contexts

VLANs, Maximum

Base (DES)


2

200



5 10 20

1

50

1.

See the


.

2.

See the


.

4-6


OL-20339-01



Table 4-5






1

Disabled


GTP/GPRS

Intercompany Media

Engine

1

Disabled

Disabled





Proxy Sessions

1

2

VPN Licenses

2



1

Disabled

AnyConnect Mobile

1

Disabled


24 50 100 250 500




750 1000 2000 3000



2


10 25 50 100 250 500 750 1000 2500 5000


1



Supported


1

VPN Load Balancing

1


Encryption

Failover

Security Contexts

VLANs, Maximum

Base (DES)


2

250



5 10 20

1

50

1.

See the


2.

See the


OL-20339-01


4-7








1

Disabled


Firewall Conns, Concurrent 5580-20: 1,000 K

GTP/GPRS

Intercompany Media

Engine

1

5580-40: 2,000 K

Disabled

Disabled




Proxy Sessions

1

2


24 50 100

VPN Licenses

3



1

AnyConnect Mobile

1

Disabled

Disabled

250 500




750 1000 2000 3000 5000 10000



2


10 25 50 100 250 500 750 1000 2500 5000


1



1

VPN Load Balancing

1



Supported

2

Encryption

Failover

Security Contexts

VLANs, Maximum

Base (DES)


2

250



5 10 20

1

50

1.

See the


.

2.

With the 10,000-session license, the total combined sessions can be 10,000, but the maximum number of Phone Proxy sessions is 5000.

3.

See the


.

4-8


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License Notes

Table 4-7

Table 4-7

includes common footnotes shared by multiple tables in the

“Licenses Per Model” section on page 4-2

.

License Notes

License

Active/Active Failover


Notes

You cannot use Active/Active failover and VPN; if you want to use VPN, use Active/Standby failover.

This license enables AnyConnect VPN client access to the adaptive security appliance. This license does not support browser-based (clientless) SSL VPN access or Cisco Secure Desktop.

For these features, activate an AnyConnect Premium SSL VPN Edition license instead of the

AnyConnect Essentials license.

Note

With the AnyConnect Essentials license, VPN users can use a Web browser to log in, and download and start (WebLaunch) the AnyConnect client.

The AnyConnect client software offers the same set of client features, whether it is enabled by this license or an AnyConnect Premium SSL VPN Edition license.

The AnyConnect Essentials license cannot be active at the same time as the following licenses on a given adaptive security appliance: AnyConnect Premium SSL VPN Edition license (all types) or the Advanced Endpoint Assessment license. You can, however, run AnyConnect Essentials and AnyConnect Premium SSL VPN Edition licenses on different adaptive security appliances in the same network.

By default, the adaptive security appliance uses the AnyConnect Essentials license, but you can disable it to use other licenses by using theConfiguration > Remote Access VPN > Network

(Client) Access > Advanced > AnyConnect Essentials pane.

AnyConnect Mobile

AnyConnect Premium

SSL VPN Edition Shared

See also the


This license provides access to the AnyConnect Client for touch-screen mobile devices running

Windows Mobile 5.0, 6.0, and 6.1. We recommend using this license if you want to support mobile access to AnyConnect 2.3 and later versions. This license requires activation of one of the following licenses to specify the total number of SSL VPN sessions permitted: AnyConnect

Essentials or AnyConnect Premium SSL VPN Edition.

A shared license lets the adaptive security appliance act as a shared license server for multiple client adaptive security appliances. The shared license pool is large, but the maximum number of sessions used by each individual adaptive security appliance cannot exceed the maximum number listed for permanent licenses.


Combined IPSec and SSL

VPN sessions

Requires a Strong Encryption (3DES/AES) License to download the dynamic database.

•

Although the maximum IPSec and SSL VPN sessions add up to more than the maximum VPN sessions, the combined sessions should not exceed the VPN session limit. If you exceed the maximum VPN sessions, you can overload the adaptive security appliance, so be sure to size your network appropriately.

•

If you start a clientless SSL VPN session and then start an AnyConnect client session from the portal, 1 session is used in total. However, if you start the AnyConnect client first (from a standalone client, for example) and then log into the clientless SSL VPN portal, then 2 sessions are used.

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4-9



Table 4-7 License Notes (continued)

License

Intercompany Media

Engine

Notes

When you enable the Intercompany Media Engine (IME) license, you can use TLS proxy sessions up to the platform limit. If you also install the Unified Communications (UC) license, then the sessions available for UC are also available for IME sessions. For example, if the platform limit is 1000 TLS proxy sessions, and you purchase a 750-session UC license, then the first 250 IME sessions do not affect the sessions available for UC. If you need more than 250 sessions for IME, then the remaining 750 sessions of the platform limit are used on a first-come, first-served basis by UC and IME.

•

Note

For a license part number ending in “K8”, TLS proxy sessions are limited to 1000.

For a license part number ending in “K9”, the TLS proxy limit depends on your configuration and the platform model. To configure the TLS proxy limit, use the

Configuration > Firewall > Unified Communications > TLS Proxy pane.K8 and K9 refer to whether the license is restricted for export: K8 is unrestricted, and K9 is restricted.

You might also use SRTP encryption sessions for your connections:

•

•

For a K8 license, SRTP sessions are limited to 250.

For a K9 license, there is not limit.


Proxy sessions

Note

Note

Only calls that require encryption/decryption for media are counted towards the SRTP limit; if passthrough is set for the call, even if both legs are SRTP, they do not count towards the limit.

Phone Proxy, Presence Federation Proxy, and Encrypted Voice Inspection applications use TLS proxy sessions for their connections. Each TLS proxy session is counted against the UC license limit. All of these applications are licensed under the UC Proxy umbrella, and can be mixed and matched. Some applications might use multiple sessions for a connection. For example, if you configure a phone with a primary and backup Cisco Unified Communications Manager, there are

2 TLS proxy connections, so 2 UC Proxy sessions are used.

Mobility Advantage Proxy does not require a license, and its TLS proxy sessions do not count towards the UC license limit.

VPN load balancing

The maximum number of UC sessions you can use also depends on the TLS proxy session limit:

•

Note

For license part numbers ending in “K8” (for example, licenses under 250 users), TLS proxy sessions are limited to 1000.

For license part numbers ending in “K9” (for example, licenses 250 users or larger), the

TLS proxy limit depends on your configuration and the platform model. To configure the

TLS proxy limit, use the Configuration > Firewall > Unified Communications > TLS

Proxy pane.Note: K8 and K9 refer to whether the license is restricted for export: K8 is unrestricted, and K9 is restricted.


•

•

For K8 licenses, SRTP sessions are limited to 250.

For K9 licenses, there is not limit.

Note


Requires a Strong Encryption (3DES/AES) License.

4-10


OL-20339-01


Information About Feature Licenses

VPN License and Feature Compatibility

Table 4-8

shows how the VPN licenses and features can combine.

For a detailed list of the features supported by the AnyConnect Essentials license and AnyConnect

Premium SSL VPN Edition license, see

AnyConnect Secure Mobility Client Features, Licenses, and OSs,

Release 2.5

: http://www.cisco.com/en/US/docs/security/vpn_client/anyconnect/anyconnect25/feature/guide/anycon nect25features.html#wp43883

Table 4-8 VPN License and Feature Compatibility

Supported with:

Enable one of the following licenses:

1

AnyConnect Essentials

AnyConnect Premium

SSL VPN Edition

AnyConnect Mobile

Advanced Endpoint Assessment

Yes

No

AnyConnect Premium SSL VPN Edition Shared

No

Client-based SSL VPN

Yes

Browser-based (clientless) SSL VPN

IPsec VPN

No

Yes

VPN Load Balancing

Cisco Secure Desktop

Yes

No

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

1.

You can only have one license type active, either the AnyConnect Essentials license or the AnyConnect Premium license. By default, the adaptive security appliance includes an AnyConnect Premium license for 2 sessions. If you install the

AnyConnect Essentials license, then it is used by default. See the Configuration > Remote Access VPN > Network (Client)

Access > Advanced > AnyConnect Essentials pane to enable the Premium license instead.


A license specifies the options that are enabled on a given adaptive security appliance. It is represented by an activation key that is a 160-bit (5 32-bit words or 20 bytes) value. This value encodes the serial number (an 11 character string) and the enabled features.


•

Preinstalled License, page 4-12

•

•

•

•

•

Permanent License, page 4-12

Time-Based Licenses, page 4-12

Shared SSL VPN Licenses, page 4-14

Failover Licenses, page 4-19

Licenses FAQ, page 4-20

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4-11



Preinstalled License

By default, your adaptive security appliance ships with a license already installed. This license might be the Base License, to which you want to add more licenses, or it might already have all of your licenses

installed, depending on what you ordered and what your vendor installed for you. See the “Viewing Your

Current License” section on page 4-23 section to determine which licenses you have installed.

Permanent License

You can have one permanent activation key installed. The permanent activation key includes all licensed features in a single key. If you also install time-based licenses, the adaptive security appliance combines the permanent and time-based licenses into a running license. See the

“How Permanent and Time-Based

Licenses Combine” section on page 4-13 for more information about how the adaptive security

appliance combines the licenses.

Time-Based Licenses

In addition to permanent licenses, you can purchase time-based licenses or receive an evaluation license that has a time-limit. For example, you might buy a time-based SSL VPN license to handle short-term surges in the number of concurrent SSL VPN users, or you might order a Botnet Traffic Filter time-based license that is valid for 1 year.


•

•

•

•

•

Time-Based License Activation Guidelines, page 4-12

How the Time-Based License Timer Works, page 4-12

How Permanent and Time-Based Licenses Combine, page 4-13

Stacking Time-Based Licenses, page 4-14

Time-Based License Expiration, page 4-14

Time-Based License Activation Guidelines

•

•

You can install multiple time-based licenses, including multiple licenses for the same feature.

However, only one time-based license per feature can be

active

at a time. The inactive license remains installed, and ready for use. For example, if you install a 1000-session SSL VPN license, and a 2500-session SSL VPN license, then only one of these licenses can be active.

If you activate an evaluation license that has multiple features in the key, then you cannot also activate another time-based license for one of the included features. For example, if an evaluation license includes the Botnet Traffic Filter and a 1000-session SSL VPN license, you cannot also activate a standalone time-based 2500-session SSL VPN license.

How the Time-Based License Timer Works

•

•

The timer for the time-based license starts counting down when you activate it on the adaptive security appliance.

If you stop using the time-based license before it times out, then the timer halts. The timer only starts again when you reactivate the time-based license.

4-12


OL-20339-01



•

If the time-based license is active, and you shut down the adaptive security appliance, then the timer continues to count down. If you intend to leave the adaptive security appliance in a shut down state for an extended period of time, then you should deactivate the time-based license before you shut down.

Note

We suggest you do not change the system clock after you install the time-based license. If you set the clock to be a later date, then if you reload, the adaptive security appliance checks the system clock against the original installation time, and assumes that more time has passed than has actually been used.

If you set the clock back, and the actual running time is greater than the time between the original installation time and the system clock, then the license immediately expires after a reload.

How Permanent and Time-Based Licenses Combine

When you activate a time-based license, then features from both permanent and time-based licenses combine to form the running license. How the permanent and time-based licenses combine depends on

the type of license. Table 4-9 lists the combination rules for each feature license.

Note

Even when the permanent license is used, if the time-based license is active, it continues to count down.

Table 4-9


Proxy Sessions

All Others

Time-Based License Combination Rules

Time-Based Feature

SSL VPN Sessions

Security Contexts


Combined License Rule

The higher value is used, either time-based or permanent. For example, if the permanent license is 1000 sessions, and the time-based license is

2500 sessions, then 2500 sessions are enabled. Typically, you will not install a time-based license that has less capability than the permanent license, but if you do so, then the permanent license is used.

The time-based license sessions are added to the permanent sessions, up to the platform limit. For example, if the permanent license is 2500 sessions, and the time-based license is 1000 sessions, then 3500 sessions are enabled for as long as the time-based license is active.

The time-based license contexts are added to the permanent contexts, up to the platform limit. For example, if the permanent license is 10 contexts, and the time-based license is 20 contexts, then 30 contexts are enabled for as long as the time-based license is active.

There is no permanent Botnet Traffic Filter license available; the time-based license is used.

The higher value is used, either time-based or permanent. For licenses that have a status of enabled or disabled, then the license with the enabled status is used. For licenses with numerical tiers, the higher value is used. Typically, you will not install a time-based license that has less capability than the permanent license, but if you do so, then the permanent license is used.

To view the combined license, see the

“Viewing Your Current License” section on page 4-23

.

OL-20339-01


4-13



Stacking Time-Based Licenses

In many cases, you might need to renew your time-based license and have a seamless transition from the old license to the new one. For features that are only available with a time-based license, it is especially important that the license not expire before you can apply the new license. The adaptive security appliance allows you to

stack

time-based licenses so you do not have to worry about the license expiring or about losing time on your licenses because you installed the new one early.

When you install an identical time-based license as one already installed, then the licenses are combined, and the duration equals the combined duration.

For example:

1.

You install a 52-week Botnet Traffic Filter license, and use the license for 25 weeks (27 weeks remain).

2.

You then purchase another 52-week Botnet Traffic Filter license. When you install the second license, the licenses combine to have a duration of 79 weeks (52 weeks plus 27 weeks).

Similarly:

1.

2.

You install an 8-week 1000-session SSL VPN license, and use it for 2 weeks (6 weeks remain).

You then install another 8-week 1000-session license, and the licenses combine to be 1000-sessions for 14 weeks (8 weeks plus 6 weeks).

If the licenses are not identical (for example, a 1000-session SSL VPN license vs. a 2500-session license), then the licenses are

not

combined. Because only one time-based license per feature can be active, only one of the licenses can be active. See the

“Activating or Deactivating Keys” section on page 4-24 for more information about activating licenses.

Although non-identical licenses do not combine, when the current license expires, the adaptive security appliance automatically activates an installed license of the same feature if available. See the

“Time-Based License Expiration” section on page 4-14 for more information.

Time-Based License Expiration

When the current license for a feature expires, the adaptive security appliance automatically activates an installed license of the same feature if available. If there are no other time-based licenses available for the feature, then the permanent license is used.

If you have more than one additional time-based license installed for a feature, then the adaptive security appliance uses the first license it finds; which license is used is not user-configurable and depends on internal operations. If you prefer to use a different time-based license than the one the adaptive security

appliance activated, then you must manually activate the license you prefer. See the “Activating or

Deactivating Keys” section on page 4-24 .

For example, you have a time-based 2500-session SSL VPN license (active), a time-based 1000-session

SSL VPN license (inactive), and a permanent 500-session SSL VPN license. While the 2500-session license expires, the adaptive security appliance activates the 1000-session license. After the

1000-session license expires, the adaptive security appliance uses the 500-session permanent license.

Shared SSL VPN Licenses

A shared license lets you purchase a large number of SSL VPN sessions and share the sessions as needed among a group of adaptive security appliances by configuring one of the adaptive security appliances as a shared licensing server, and the rest as shared licensing participants. This section describes how a shared license works and includes the following topics:


4-14 OL-20339-01



•

•

•

•

•

Information About the Shared Licensing Server and Participants, page 4-15

Communication Issues Between Participant and Server, page 4-16

Information About the Shared Licensing Backup Server, page 4-16

Failover and Shared Licenses, page 4-17

Maximum Number of Participants, page 4-18

Information About the Shared Licensing Server and Participants

The following steps describe how shared licenses operate:

1.

Decide which adaptive security appliance should be the shared licensing server, and purchase the shared licensing server license using that device serial number.

2.

3.

Decide which adaptive security appliances should be shared licensing participants, including the shared licensing backup server, and obtain a shared licensing participant license for each device, using each device serial number.

(Optional) Designate a second adaptive security appliance as a shared licensing backup server. You can only specify one backup server.

Note

The shared licensing backup server only needs a participant license.

4.

5.

Configure a shared secret on the shared licensing server; any participants with the shared secret can use the shared license.

When you configure the adaptive security appliance as a participant, it registers with the shared licensing server by sending information about itself, including the local license and model information.

Note

The participant needs to be able to communicate with the server over the IP network; it does not have to be on the same subnet.

6.

7.

8.

The shared licensing server responds with information about how often the participant should poll the server.

When a participant uses up the sessions of the local license, it sends a request to the shared licensing server for additional sessions in 50-session increments.

The shared licensing server responds with a shared license. The total sessions used by a participant cannot exceed the maximum sessions for the platform model.

Note

The shared licensing server can also participate in the shared license pool. It does not need a participant license as well as the server license to participate.

9.

a.

If there are not enough sessions left in the shared license pool for the participant, then the server responds with as many sessions as available.

b.

The participant continues to send refresh messages requesting more sessions until the server can adequately fulfill the request.

When the load is reduced on a participant, it sends a message to the server to release the shared sessions.

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4-15



Note

The adaptive security appliance uses SSL between the server and participant to encrypt all communications.

Communication Issues Between Participant and Server

See the following guidelines for communication issues between the participant and server:

•

•

If a participant fails to send a refresh after 3 times the refresh interval, then the server releases the sessions back into the shared license pool.

If the participant cannot reach the license server to send the refresh, then the participant can continue to use the shared license it received from the server for up to 24 hours.

•

•

If the participant is still not able to communicate with a license server after 24 hours, then the participant releases the shared license, even if it still needs the sessions. The participant leaves existing connections established, but cannot accept new connections beyond the license limit.

If a participant reconnects with the server before 24 hours expires, but after the server expired the participant sessions, then the participant needs to send a new request for the sessions; the server responds with as many sessions as can be reassigned to that participant.

Information About the Shared Licensing Backup Server

The shared licensing backup server must register successfully with the main shared licensing server before it can take on the backup role. When it registers, the main shared licensing server syncs server settings as well as the shared license information with the backup, including a list of registered participants and the current license usage. The main server and backup server sync the data at 10 second intervals. After the initial sync, the backup server can successfully perform backup duties, even after a reload.

When the main server goes down, the backup server takes over server operation. The backup server can operate for up to 30 continuous days, after which the backup server stops issuing sessions to participants, and existing sessions time out. Be sure to reinstate the main server within that 30-day period.

Critical-level syslog messages are sent at 15 days, and again at 30 days.

When the main server comes back up, it syncs with the backup server, and then takes over server operation.

When the backup server is not active, it acts as a regular participant of the main shared licensing server.

Note

When you first launch the main shared licensing server, the backup server can only operate independently for 5 days. The operational limit increases day-by-day, until 30 days is reached. Also, if the main server later goes down for any length of time, the backup server operational limit decrements day-by-day. When the main server comes back up, the backup server starts to increment again day-by-day. For example, if the main server is down for 20 days, with the backup server active during that time, then the backup server will only have a 10-day limit left over. The backup server “recharges” up to the maximum 30 days after 20 more days as an inactive backup. This recharging function is implemented to discourage misuse of the shared license.

4-16


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Failover and Shared Licenses

This section describes how shared licenses interact with failover and includes the following topics:

•

“Failover and Shared License Servers” section on page 4-17

•

“Failover and Shared License Participants” section on page 4-18

Failover and Shared License Servers

This section describes how the main server and backup server interact with failover. Because the shared licensing server is also performing normal duties as the adaptive security appliance, including performing functions such as being a VPN gateway and firewall, then you might need to configure failover for the main and backup shared licensing servers for increased reliability.

Note

The backup server mechanism is separate from, but compatible with, failover.

Shared licenses are supported only in single context mode, so Active/Active failover is not supported.

For Active/Standby failover, the primary unit acts as the main shared licensing server, and the standby unit acts as the main shared licensing server after failover. The standby unit does

not

act as the backup shared licensing server. Instead, you can have a second pair of units acting as the backup server, if desired.

For example, you have a network with 2 failover pairs. Pair #1 includes the main licensing server. Pair

#2 includes the backup server. When the primary unit from Pair #1 goes down, the standby unit immediately becomes the new main licensing server. The backup server from Pair #2 never gets used.

Only if both units in Pair #1 go down does the backup server in Pair #2 come into use as the shared licensing server. If Pair #1 remains down, and the primary unit in Pair #2 goes down, then the standby unit in Pair #2 comes into use as the shared licensing server (see

Figure 4-1 ).

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4-17



Figure 4-1 Failover and Shared License Servers

Key

Blue=Shared license server in use

(

Active

)=Active failover unit

Failover Pair #1

1. Normal operation:

Main (

Active

) Main (Standby)



Backup (

Active

) Backup (Standby)


2. Primary main server fails over:

Main (Failed) Main (


Active

) Backup (

Active

) Backup (Standby)


3 . Both main servers fail:

Main (Failed) Main (Failed)


Backup (

Active

) Backup (Standby)


4. Both main servers and primary backup fail:

Main (Failed) Main (Failed) Backup (Failed) Backup (

Active

)

The standby backup server shares the same operating limits as the primary backup server; if the standby unit becomes active, it continues counting down where the primary unit left off. See the

“Information

About the Shared Licensing Backup Server” section on page 4-16 for more information.

Failover and Shared License Participants

For participant pairs, both units register with the shared licensing server using separate participant IDs.

The active unit syncs its participant ID with the standby unit. The standby unit uses this ID to generate a transfer request when it switches to the active role. This transfer request is used to move the shared sessions from the previously active unit to the new active unit.

Maximum Number of Participants

The adaptive security appliance does not limit the number of participants for the shared license; however, a very large shared network could potentially affect the performance on the licensing server. In this case, you can increase the delay between participant refreshes, or you can create two shared networks.

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Failover Licenses

Failover units do not require the same license on each unit. This section includes the following topics:

•

Failover License Requirements, page 4-19

•

•

•

How Failover Licenses Combine, page 4-19

Loss of Communication Between Failover Units, page 4-20

Upgrading Failover Pairs, page 4-20

Failover License Requirements

•

•

Failover units do not require the same license on each unit.

Older versions of adaptive security appliance software required that the licenses match on each unit.

Starting with Version 8.3(1), you no longer need to install identical licenses. Typically, you buy a license only for the primary unit; for Active/Standby failover, the secondary unit inherits the primary license when it becomes active. If you have licenses on both units, they combine into a single running failover cluster license.

For the ASA 5505 and 5510 adaptive security appliances, both units require the Security Plus license; the Base license does not support failover, so you cannot enable failover on a standby unit that only has the Base license.

How Failover Licenses Combine

For failover pairs, the licenses on each unit are combined into a single running failover cluster license.

For Active/Active failover, the license usage of the two units combined cannot exceed the failover cluster license.

If you buy separate licenses for the primary and secondary unit, then the combined license uses the following rules:

•

For licenses that have numerical tiers, such as the number of sessions, the values from both the primary and secondary licenses are combined up to the platform limit. If both licenses in use are time-based, then the licenses count down simultaneously.

For example, you have two ASA 5520 adaptive security appliances with 500 SSL VPN sessions each; because the platform limit is 750, the combined license allows 750 SSL VPN sessions.

Note

In the above example, if the SSL VPN licenses are time-based, you might want to disable one of the licenses so you do not “waste” a 500 session license from which you can only use

250 sessions because of the platform limit.

•

•

Or you have two ASA 5540 adaptive security appliances, one with 20 contexts and the other with

10 contexts; the combined license allows 30 contexts. For Active/Active failover, for example, one unit can use 18 contexts and the other unit can use 12 contexts, for a total of 30; the combined usage cannot exceed the failover cluster license.

For licenses that have a status of enabled or disabled, then the license with the enabled status is used.

For time-based licenses that are enabled or disabled (and do not have numerical tiers), the duration is the combined duration of both licenses. The primary unit counts down its license first, and when it expires, the secondary unit starts counting down its license. This rule also applies to Active/Active failover, even though both units are actively operating.


OL-20339-01 4-19



For example, if you have 48 weeks left on the Botnet Traffic Filter license on both units, then the combined duration is 96 weeks.

To view the combined license, see the

“Viewing Your Current License” section on page 4-23 .

Loss of Communication Between Failover Units

If the failover units lose communication for more than 30 days, then each unit reverts to the license installed locally. During the 30-day grace period, the combined running license continues to be used by both units.

If you restore communication during the 30-day grace period, then for time-based licenses, the time elapsed is subtracted from the primary license; if the primary license becomes expired, only then does the secondary license start to count down.

If you do not restore communication during the 30-day period, then for time-based licenses, time is subtracted from both primary and secondary licenses, if installed. They are treated as two separate licenses and do not benefit from the failover combined license. The time elapsed includes the 30-day grace period.

For example:

1.

You have a 52-week Botnet Traffic Filter license installed on both units. The combined running license allows a total duration of 104 weeks.

2.

3.

The units operate as a failover unit for 10 weeks, leaving 94 weeks on the combined license (42 weeks on the primary, and 52 weeks on the secondary).

If the units lose communication (for example the primary unit fails over to the secondary unit), the secondary unit continues to use the combined license, and continues to count down from 94 weeks.

4.

•

•

The time-based license behavior depends on when communication is restored:

Within 30 days—The time elapsed is subtracted from the primary unit license. In this case, communication is restored after 4 weeks. Therefore, 4 weeks are subtracted from the primary license leaving 90 weeks combined (38 weeks on the primary, and 52 weeks on the secondary).

After 30 days—The time elapsed is subtracted from both units. In this case, communication is restored after 6 weeks. Therefore, 6 weeks are subtracted from both the primary and secondary licenses, leaving 84 weeks combined (36 weeks on the primary, and 46 weeks on the secondary).

Upgrading Failover Pairs

Because failover pairs do not require the same license on both units, you can apply new licenses to each unit without any downtime. If you apply a permanent license that requires a reload (see

Table 4-10 on page 4-24 ), then you can fail over to the other unit while you reload. If both units require reloading, then

you can reload them separately so you have no downtime.

Licenses FAQ

Q.

Can I activate multiple time-based licenses, for example, SSL VPN and Botnet Traffic Filter?

A.

Yes. You can use one time-based license per feature at a time.

Q.

Can I “stack” time-based licenses so that when the time limit runs out, it will automatically use the next license?

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OL-20339-01


Guidelines and Limitations

A.

Yes. For identical licenses, the time limit is combined when you install multiple time-based licenses.

For non-identical licenses (for example, a 1000-session SSL VPN license and a 2500-session license), the adaptive security appliance automatically activates the next time-based license it finds for the feature.

Q.

Can I install a new permanent license while maintaining an active time-based license?

A.

Yes. Activating a permanent license does not affect time-based licenses.

Q.

For failover, can I use a shared licensing server as the primary unit, and the shared licensing backup server as the secondary unit?

A.

No. The secondary unit has the same running license as the primary unit; in the case of the shared licensing server, they require a server license. The backup server requires a participant license. The backup server can be in a separate failover pair of two backup servers.

Q.

Do I need to buy the same licenses for the secondary unit in a failover pair?

A.

No. Typically, you buy a license only for the primary unit; the secondary unit inherits the primary license when it becomes active. In the case where you also have a separate license on the secondary unit, the licenses are combined into a running failover cluster license.

Q.

Can I use a time-based or permanent SSL VPN license in addition to a shared SSL VPN license?

A.

Yes. The shared license is used only after the sessions from the locally installed license (time-based or permanent) are used up.

Note

: On the shared licensing server, the permanent SSL VPN license is not used; you can however use a time-based license at the same time as the shared licensing server license. In this case, the time-based license sessions are available for local SSL VPN sessions only; they cannot be added to the shared licensing pool for use by participants.


See the following guidelines for activation keys.

Context Mode Guidelines

•

In multiple context mode, apply the activation key in the system execution space.

•

Shared licenses are not supported in multiple context mode.

Firewall Mode Guidelines

All license types are available in both routed and transparent mode.

Failover Guidelines

•

Shared licenses are not supported in Active/Active mode. See the

“Failover and Shared Licenses” section on page 4-17 for more information.

•

Failover units do not require the same license on each unit.

Older versions of adaptive security appliance software required that the licenses match on each unit.

Starting with Version 8.3(1), you no longer need to install identical licenses. Typically, you buy a license only for the primary unit; for Active/Standby failover, the secondary unit inherits the primary license when it becomes active. If you have licenses on both units, they combine into a single running failover cluster license.

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4-21



4-22

Note

Failover units do require the same RAM on both units.

•

For the ASA 5505 and 5510 adaptive security appliances, both units require the Security Plus license; the Base license does not support failover, so you cannot enable failover on a standby unit that only has the Base license.

Upgrade and Downgrade Guidelines

Your activation key remains compatible if you upgrade to the latest version from any previous version.

However, you might have issues if you want to maintain downgrade capability:

•

Downgrading to Version 8.1 or earlier—After you upgrade, if you activate additional feature licenses that were introduced

before 8.2

, then the activation key continues to be compatible with earlier versions if you downgrade. However if you activate feature licenses that were introduced in

8.2 or later

, then the activation key is not backwards compatible. If you have an incompatible license key, then see the following guidelines:

–

–

If you previously entered an activation key in an earlier version, then the adaptive security appliance uses that key (without any of the new licenses you activated in Version 8.2 or later).

If you have a new system and do not have an earlier activation key, then you need to request a new activation key compatible with the earlier version.

•

Downgrading to Version 8.2 or earlier—Version 8.3 introduced more robust time-based key usage as well as failover license changes:

–

If you have more than one time-based activation key active, when you downgrade, only the most recently activated time-based key can be active. Any other keys are made inactive. If the last time-based license is for a feature introduced in 8.3, then that license still remains the active license even though it cannot be used in earlier versions. Reenter the permanent key or a valid time-based key.

–

–

If you have mismatched licenses on a failover pair, then downgrading will disable failover. Even if the keys are matching, the license used will no longer be a combined license.

If you have one time-based license installed, but it is for a feature introduced in 8.3, then after you downgrade, that time-based license remains active. You need to reenter the permanent key to disable the time-based license.

Additional Guidelines and Limitations

•

The activation key is not stored in your configuration file; it is stored as a hidden file in flash memory.

•

The activation key is tied to the serial number of the device. Feature licenses cannot be transferred between devices (except in the case of a hardware failure). If you have to replace your device due to a hardware failure, contact the Cisco Licensing Team to have your existing license transferred to the new serial number. The Cisco Licensing Team will ask for the Product Authorization Key reference number and existing serial number.

•

•

Once purchased, you cannot return a license for a refund or for an upgraded license.

Although you can activate all license types, some features are incompatible with each other; for example, multiple context mode and VPN. In the case of the AnyConnect Essentials license, the license is incompatible with the following licenses: full SSL VPN license, shared SSL VPN license, and Advanced Endpoint Assessment license. By default, the AnyConnect Essentials license is used instead of the above licenses, but you can disable the AnyConnect Essentials license in the configuration to restore use of the other licenses using the Configuration > Remote Access VPN >

Network (Client) Access > Advanced > AnyConnect Essentials pane.


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Viewing Your Current License

Viewing Your Current License

This section describes how to view your current license, and for time-based activation keys, how much time the license has left.

Detailed Steps

Step 1

Step 2

Step 3

To view the running license, which is a combination of the permanent license and any active time-based licenses, choose the

Configuration > Device Management > Licensing > Activation Key

pane and view the Running Licenses area.

In multiple context mode, view the activation key in the System execution space by choosing the

Configuration > Device Management > Activation Key

pane.

For a failover pair, the running license shown is the combined license from the primary and secondary units. See the

“How Failover Licenses Combine” section on page 4-19 for more information. For

time-based licenses with numerical values (the duration is not combined), the License Duration column displays the shortest time-based license from either the primary or secondary unit; when that license expires, the license duration from the other unit displays.

(Optional) To view time-based license details, such as the features included in the license and the duration, in the Time-Based License Keys Installed area, choose a license key, and then click

Show

License Details

.

(Optional) For a failover unit, to view the license installed on this unit (and not the combined license from both primary and secondary units), in the Running Licenses area, click

Show information of license specifically purchased for this device alone

.

Obtaining an Activation Key

To obtain an activation key, you need a Product Authorization Key, which you can purchase from your

Cisco account representative. You need to purchase a separate Product Activation Key for each feature license. For example, if you have the Base License, you can purchase separate keys for Advanced

Endpoint Assessment and for additional SSL VPN sessions.

After obtaining the Product Authorization Keys, register them on Cisco.com by performing the following steps.

Detailed Steps

Step 1

Step 2

Obtain the serial number for your adaptive security appliance by choosing Configuration > Device

Management > Licensing > Activation Key (in multiple context mode, view the serial number in the

System execution space).

Access one of the following URLs.

•

Use the following website if you are a registered user of Cisco.com: http://www.cisco.com/go/license

•

Use the following website if you are not a registered user of Cisco.com: http://www.cisco.com/go/license/public

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4-23


Activating or Deactivating Keys

Step 3

Step 4

Enter the following information, when prompted:

•

•

Product Authorization Key (if you have multiple keys, enter one of the keys first. You have to enter each key as a separate process.)

The serial number of your adaptive security appliance

•

Your email address

An activation key is automatically generated and sent to the email address that you provide. This key includes all features you have registered so far for permanent licenses. For time-based licenses, each license has a separate activation key.

If you have additional Product Authorization Keys, repeat

Step 3

for each Product Authorization Key.

After you enter all of the Product Authorization Keys, the final activation key provided includes all of the permanent features you registered.

Activating or Deactivating Keys

This section describes how to enter a new activation key, and how to activate and deactivate time-based keys.

Prerequisites

•

•

If you are already in multiple context mode, enter the activation key in the system execution space.

Some permanent licenses require you to reload the adaptive security appliance after you activate them.

Table 4-10 lists the licenses that require reloading.

Table 4-10

All models

All models

Permanent License Reloading Requirements

Model

ASA 5505 and ASA 5510

License Action Requiring Reload

Changing between the Base and Security Plus license.

Changing the Encryption license.

Downgrading any permanent license (for example, going from 10 contexts to 2 contexts).

Limitations and Restrictions



•

Downgrading to Version 8.1 or earlier—After you upgrade, if you activate additional feature licenses that were introduced

before 8.2

, then the activation key continues to be compatible with earlier versions if you downgrade. However if you activate feature licenses that were introduced in

8.2 or later

, then the activation key is not backwards compatible. If you have an incompatible license key, then see the following guidelines:

–

If you previously entered an activation key in an earlier version, then the adaptive security appliance uses that key (without any of the new licenses you activated in Version 8.2 or later).

–



4-24 OL-20339-01


Configuring a Shared License

•

Downgrading to Version 8.2 or earlier—Version 8.3 introduced more robust time-based key usage as well as failover license changes:

–

–

If you have more than one time-based activation key active, when you downgrade, only the most recently activated time-based key can be active. Any other keys are made inactive.


Detailed Steps

Step 1

Step 2

Step 3

Step 4

Choose the

Configuration > Device Management > Licensing > Activation Key

pane.

To enter a new activation key, either permanent or time-based, enter the new activation key in the New

Activation Key field.

The key is a five-element hexadecimal string with one space between each element. The leading 0x specifier is optional; all values are assumed to be hexadecimal. For example:

0xd11b3d48 0xa80a4c0a 0x48e0fd1c 0xb0443480 0x843fc490

You can install one permanent key, and multiple time-based keys. If you enter a new permanent key, it overwrites the already installed one. If you enter a new time-based key, then it is active by default and displays in the Time-based License Keys Installed table. The last time-based key that you activate for a given feature is the active one.

To activate or deactivate an installed time-based key, choose the key in the Time-based License Keys

Installed table, and click either

Activate

or

Deactivate

.

You can only have one time-based key active for each feature. See the

“Time-Based Licenses” section on page 4-12 for more information.

Click

Update Activation Key

.

Some permanent licenses require you to reload the adaptive security appliance after entering the new activation key. See


for a list of licenses that need reloading. You will be prompted to reload if it is required.


This section describes how to configure the shared licensing server and participants. For more information about shared licenses, see the

“Shared SSL VPN Licenses” section on page 4-14 .


•

Configuring the Shared Licensing Server, page 4-25

•

•

Configuring the Shared Licensing Participant and the Optional Backup Server, page 4-26

Monitoring the Shared License, page 4-27

Configuring the Shared Licensing Server

This section describes how to configure the adaptive security appliance to be a shared licensing server.

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Prerequisites

The server must have a shared licensing server key.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Choose the

Configuration > Device Management > Licenses > Shared SSL VPN Licenses

pane.

In the Shared Secret field, enter the shared secret as a string between 4 and 128 ASCII characters.

Any participant with this secret can use the license server.

(Optional) In the TCP IP Port field, enter the port on which the server listens for SSL connections from participants, between 1 and 65535.

The default is TCP port 50554.

(Optional) In the Refresh interval field, enter the refresh interval between 10 and 300 seconds.

This value is provided to participants to set how often they should communicate with the server. The default is 30 seconds.

In the Interfaces that serve shared licenses area, check the

Shares Licenses

check box for any interfaces on which participants contact the server.

(Optional) To identify a backup server, in the Optional backup shared SSL VPN license server area:

a.

b.

In the Backup server IP address field, enter the backup server IP address.

In the Primary backup server serial number field, enter the backup server serial number.

c.

If the backup server is part of a failover pair, identify the standby unit serial number in the Secondary backup server serial number field.

You can only identify 1 backup server and its optional standby unit.

Click

Apply

.

What to Do Next

See the

“Configuring the Shared Licensing Participant and the Optional Backup Server” section on page 4-26 .

Configuring the Shared Licensing Participant and the Optional Backup Server

This section configures a shared licensing participant to communicate with the shared licensing server; this section also describes how you can optionally configure the participant as the backup server.

Prerequisites

The participant must have a shared licensing participant key.

Detailed Steps

Step 1

Step 2

Choose the

Configuration > Device Management > Licenses > Shared SSL VPN Licenses

pane.

In the Shared Secret field, enter the shared secret as a string between 4 and 128 ASCII characters.

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Feature History for Licensing

Step 3

Step 4

Step 5

(Optional) In the TCP IP Port field, enter the port on which to communicate with the server using SSL, between 1 and 65535.

The default is TCP port 50554.

(Optional) To identify the participant as the backup server, in the Select backup role of participant area:

a.

b.

Click the

Backup Server

radio button.

Check the

Shares Licenses

check box for any interfaces on which participants contact the backup server.

Click

Apply

.

Monitoring the Shared License

To monitor the shared license, choose

Monitoring > VPN > Clientless SSL VPN > Shared Licenses

.


Table 4-11

lists the release history for this feature.

Table 4-11 Feature History for Licensing

Feature Name

Increased Connections and VLANs

SSL VPN Licenses

Increased SSL VPN Licenses

Releases

7.0(5)

7.1(1)

7.2(1)

Feature Information

Increased the following limits:

•

ASA5510 Base license connections from 32000 to

5000; VLANs from 0 to 10.

•

•

ASA5510 Security Plus license connections from

64000 to 130000; VLANs from 10 to 25.

ASA5520 connections from 130000 to 280000; VLANs from 25 to 100.

•

ASA5540 connections from 280000 to 400000; VLANs from 100 to 200.

SSL VPN licenses were introduced.

A 5000-user SSL VPN license was introduced for the ASA

5550 and above.

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4-27



Table 4-11 Feature History for Licensing (continued)

Feature Name

Increased VLANs

Releases

7.2(2)

Gigabit Ethernet Support for the ASA 5510

Security Plus License

7.2(3)


The maximum number of VLANs for the Security Plus license on the ASA 5505 adaptive security appliance was increased from 5 (3 fully functional; 1 failover; one restricted to a backup interface) to 20 fully functional interfaces. In addition, the number of trunk ports was increased from 1 to 8. Now there are 20 fully functional interfaces, you do not need to use the backup interface command to cripple a backup ISP interface; you can use a fully-functional interface for it. The backup interface command is still useful for an Easy VPN configuration.

VLAN limits were also increased for the ASA 5510 adaptive security appliance (from 10 to 50 for the Base license, and from 25 to 100 for the Security Plus license), the ASA 5520 adaptive security appliance (from 100 to

150), the ASA 5550 adaptive security appliance (from 200 to 250).

The ASA 5510 adaptive security appliance now supports

Gigabit Ethernet (1000 Mbps) for the Ethernet 0/0 and 0/1 ports with the Security Plus license. In the Base license, they continue to be used as Fast Ethernet (100 Mbps) ports.

Ethernet 0/2, 0/3, and 0/4 remain as Fast Ethernet ports for both licenses.

Note

The interface names remain Ethernet 0/0 and

Ethernet 0/1.

Advanced Endpoint Assessment License

VPN Load Balancing for the ASA 5510

8.0(2)

8.0(2)

The Advanced Endpoint Assessment license was introduced. As a condition for the completion of a Cisco

AnyConnect or clientless SSL VPN connections, the remote computer scans for a greatly expanded collection of antivirus and antispyware applications, firewalls, operating systems, and associated updates. It also scans for any registry entries, filenames, and process names that you specify. It sends the scan results to the adaptive security appliance. The adaptive security appliance uses both the user login credentials and the computer scan results to assign a Dynamic Access Policy (DAP).

With an Advanced Endpoint Assessment License, you can enhance Host Scan by configuring an attempt to update noncompliant computers to meet version requirements.

Cisco can provide timely updates to the list of applications and versions that Host Scan supports in a package that is separate from Cisco Secure Desktop.

VPN load balancing is now supported on the ASA 5510

Security Plus license.

4-28


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Table 4-11

Time-based Licenses

Increased VLANs for the ASA 5580

Unified Communications Proxy Sessions license

Feature History for Licensing (continued)

Feature Name

AnyConnect for Mobile License

Botnet Traffic Filter License

AnyConnect Essentials License

Releases

8.0(3)

8.0(4)/8.1(2) Support for time-based licenses was introduced.

8.1(2) The number of VLANs supported on the ASA 5580 are increased from 100 to 250.

8.0(4) The UC Proxy sessions license was introduced. Phone

Proxy, Presence Federation Proxy, and Encrypted Voice

Inspection applications use TLS proxy sessions for their connections. Each TLS proxy session is counted against the

UC license limit. All of these applications are licensed under the UC Proxy umbrella, and can be mixed and matched.

8.2(1)

8.2(1)


The AnyConnect for Mobile license was introduced. It lets

Windows mobile devices connect to the adaptive security appliance using the AnyConnect client.

This feature is not available in Version 8.1.

The Botnet Traffic Filter license was introduced. The

Botnet Traffic Filter protects against malware network activity by tracking connections to known bad domains and

IP addresses.

The AnyConnect Essentials License was introduced. This license enables AnyConnect VPN client access to the adaptive security appliance. This license does not support browser-based SSL VPN access or Cisco Secure Desktop.

For these features, activate an AnyConnect Premium SSL

VPN Edition license instead of the AnyConnect Essentials license.

Note

With the AnyConnect Essentials license, VPN users can use a Web browser to log in, and download and start (WebLaunch) the AnyConnect client.

The AnyConnect client software offers the same set of client features, whether it is enabled by this license or an

AnyConnect Premium SSL VPN Edition license.

The AnyConnect Essentials license cannot be active at the same time as the following licenses on a given adaptive security appliance: AnyConnect Premium SSL VPN

Edition license (all types) or the Advanced Endpoint

Assessment license. You can, however, run AnyConnect

Essentials and AnyConnect Premium SSL VPN Edition licenses on different adaptive security appliances in the same network.

By default, the adaptive security appliance uses the

AnyConnect Essentials license, but you can disable it to use other licenses by using the Configuration > Remote Access

VPN > Network (Client) Access > Advanced > AnyConnect

Essentials pane.

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Table 4-11 Feature History for Licensing (continued)

Feature Name

Shared Licenses for SSL VPN

Releases

8.2(1)

Mobility Proxy application no longer requires

Unified Communications Proxy license

Non-identical failover licenses

Stackable time-based licenses

Intercompany Media Engine License

Multiple time-based licenses active at the same time

Discrete activation and deactivation of time-based licenses.

8.2(2)

8.3(1)

8.3(1)

8.3(1)

8.3(1)

8.3(1)


Shared licenses for SSL VPN were introduced. Multiple adaptive security appliances can share a pool of SSL VPN sessions on an as-needed basis.

The Mobility Proxy no longer requires the UC Proxy license.

Failover licenses no longer need to be identical on each unit.

The license used for both units is the combined license from the primary and secondary units.

The following screen was modified: Configuration > Device

Management > Licensing > Activation Key.

Time-based licenses are now stackable. In many cases, you might need to renew your time-based license and have a seamless transition from the old license to the new one. For features that are only available with a time-based license, it is especially important that the license not expire before you can apply the new license. The adaptive security appliance allows you to

stack

time-based licenses so you do not have to worry about the license expiring or about losing time on your licenses because you installed the new one early.

The IME license was introduced.

You can now install multiple time-based licenses, and have one license per feature active at a time.



You can now activate or deactivate time-based licenses using a command.

The following commands was modified:

activation-key

[

activate

|

deactivate

].



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C H A P T E R

5

Configuring the Transparent or

Routed Firewall

This chapter describes how to configure the firewall mode, routed or transparent, and how to customize transparent firewall operation.

Note

In multiple context mode, you cannot set the firewall mode separately for each context; you can only set the firewall mode for the entire adaptive security appliance.


•

Configuring the Firewall Mode, page 5-1

•

•

•

Configuring ARP Inspection for the Transparent Firewall, page 5-8

Customizing the MAC Address Table for the Transparent Firewall, page 5-11

Firewall Mode Examples, page 5-14

Configuring the Firewall Mode

This section describes routed and transparent firewall mode, and how to set the mode. This section includes the following topics:

•

Information About the Firewall Mode, page 5-1

•

•

•

•

•

Licensing Requirements for the Firewall Mode, page 5-4

Default Settings, page 5-4


Setting the Firewall Mode, page 5-7

Configuring ARP Inspection for the Transparent Firewall, page 5-8

Information About the Firewall Mode

This section describes routed and transparent firewall mode and includes the following topics:

•

Information About Routed Firewall Mode, page 5-2

•

Information About Transparent Firewall Mode, page 5-2


5-1 OL-20339-01

Chapter 5 Configuring the Transparent or Routed Firewall


Information About Routed Firewall Mode

In routed mode, the adaptive security appliance is considered to be a router hop in the network. It can use OSPF or RIP (in single context mode). Routed mode supports many interfaces. Each interface is on a different subnet. You can share interfaces between contexts.

The adaptive security appliance acts as a router between connected networks, and each interface requires an IP address on a different subnet. In single context mode, the routed firewall supports OSPF, EIGRP, and RIP. Multiple context mode supports static routes only. We recommend using the advanced routing capabilities of the upstream and downstream routers instead of relying on the adaptive security appliance for extensive routing needs.

Information About Transparent Firewall Mode

Traditionally, a firewall is a routed hop and acts as a default gateway for hosts that connect to one of its screened subnets. A transparent firewall, on the other hand, is a Layer 2 firewall that acts like a “bump in the wire,” or a “stealth firewall,” and is not seen as a router hop to connected devices.

This section describes transparent firewall mode and includes the following topics:

•

•

•

•

•

Transparent Firewall Network, page 5-2

Allowing Layer 3 Traffic, page 5-2

Allowed MAC Addresses, page 5-2

Passing Traffic Not Allowed in Routed Mode, page 5-3

•

•

BPDU Handling, page 5-3

MAC Address vs. Route Lookups, page 5-3

Using the Transparent Firewall in Your Network, page 5-4

Transparent Firewall Network

The adaptive security appliance connects the same network on its inside and outside interfaces. Because the firewall is not a routed hop, you can easily introduce a transparent firewall into an existing network.

Allowing Layer 3 Traffic

IPv4 and IPv6 traffic is allowed through the transparent firewall automatically from a higher security interface to a lower security interface, without an access list. ARPs are allowed through the transparent firewall in both directions without an access list. ARP traffic can be controlled by ARP inspection. For

Layer 3 traffic travelling from a low to a high security interface, an extended access list is required on

the low security interface. See Chapter 30, “Configuring Access Rules,” for more information.

Allowed MAC Addresses

•

•

•

The following destination MAC addresses are allowed through the transparent firewall. Any MAC address not on this list is dropped.

TRUE broadcast destination MAC address equal to FFFF.FFFF.FFFF

IPv4 multicast MAC addresses from 0100.5E00.0000 to 0100.5EFE.FFFF

•

IPv6 multicast MAC addresses from 3333.0000.0000 to 3333.FFFF.FFFF

BPDU multicast address equal to 0100.0CCC.CCCD

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•

AppleTalk multicast MAC addresses from 0900.0700.0000 to 0900.07FF.FFFF

Passing Traffic Not Allowed in Routed Mode

In routed mode, some types of traffic cannot pass through the adaptive security appliance even if you allow it in an access list. The transparent firewall, however, can allow almost any traffic through using either an extended access list (for IP traffic) or an EtherType access list (for non-IP traffic).

Note

The transparent mode adaptive security appliance does not pass CDP packets packets, or any packets that do not have a valid EtherType greater than or equal to 0x600. For example, you cannot pass IS-IS packets. An exception is made for BPDUs, which are supported.

For example, you can establish routing protocol adjacencies through a transparent firewall; you can allow OSPF, RIP, EIGRP, or BGP traffic through based on an extended access list. Likewise, protocols like HSRP or VRRP can pass through the adaptive security appliance.

Non-IP traffic (for example AppleTalk, IPX, BPDUs, and MPLS) can be configured to go through using an EtherType access list.

For features that are not directly supported on the transparent firewall, you can allow traffic to pass through so that upstream and downstream routers can support the functionality. For example, by using an extended access list, you can allow DHCP traffic (instead of the unsupported DHCP relay feature) or multicast traffic such as that created by IP/TV.

BPDU Handling

To prevent loops using the spanning tree protocol, BPDUs are passed by default. To block BPDUs, you need to configure an EtherType access list to deny them.

MAC Address vs. Route Lookups

When the adaptive security appliance runs in transparent mode, the outgoing interface of a packet is determined by performing a MAC address lookup instead of a route lookup.

Route lookups, however, are necessary for the following traffic types:

•

•

Traffic originating on the adaptive security appliance—For example, if your syslog server is located on a remote network, you must use a static route so the adaptive security appliance can reach that subnet.

Voice over IP (VoIP) traffic with inspection enabled, and the endpoint is at least one hop away from the adaptive security appliance—For example, if you use the transparent firewall between a CCM and an H.323 gateway, and there is a router between the transparent firewall and the H.323 gateway, then you need to add a static route on the adaptive security appliance for the H.323 gateway for successful call completion.

•

VoIP or DNS traffic with NAT and inspection enabled—To successfully translate the IP address inside VoIP and DNS packets, the adaptive security appliance needs to perform a route lookup.

Unless the host is on a directly-connected network, then you need to add a static route on the adaptive security appliance for the real host address that is embedded in the packet.

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Using the Transparent Firewall in Your Network

Figure 5-1

shows a typical transparent firewall network where the outside devices are on the same subnet as the inside devices. The inside router and hosts appear to be directly connected to the outside router.

Figure 5-1 Transparent Firewall Network

Internet

Network A

10.1.1.1

Management IP

10.1.1.2

10.1.1.3

192.168.1.2

Network B

Licensing Requirements for the Firewall Mode

The following table shows the licensing requirements for this feature.

Model

All models

License Requirement

Base License.

Default Settings

The default mode is routed mode.

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This section includes the guidelines and limitations for this feature.


•

The firewall mode is set for the entire system and all contexts; you cannot set the mode individually for each context.

•

For multiple context mode, set the mode in the system execution space.

•

When you change modes, the adaptive security appliance clears the running configuration because many commands are not supported for both modes. This action removes any contexts from running.

If you then re-add a context that has an existing configuration that was created for the wrong mode, the context configuration might not work correctly. Be sure to recreate your context configurations for the correct mode before you re-add them, or add new contexts with new paths for the new configurations.

Transparent Firewall Guidelines

Follow these guidelines when planning your transparent firewall network:

•

For IPv4, a management IP address is required for both management traffic and for traffic to pass through the adaptive security appliance. For multiple context mode, an IP address is required for each context.

Unlike routed mode, which requires an IP address for each interface, a transparent firewall has an

IP address assigned to the entire device. The adaptive security appliance uses this IP address as the source address for packets originating on the adaptive security appliance, such as system messages or AAA communications.

•

The management IP address must be on the same subnet as the connected network. You cannot set the subnet to a host subnet (255.255.255.255).

For IPv6, at a minimum you need to configure link-local addresses for each interface for through traffic. For full functionality, including the ability to manage the adaptive security appliance, you need to configure a global IP address for the device.

You can configure an IP address (both IPv4 and IPv6) for the Management 0/0 or Management 0/1 management-only interface. This IP address can be on a separate subnet from the main management

IP address.

The transparent adaptive security appliance uses an inside interface and an outside interface only. If your platform includes a dedicated management interface, you can also configure the management interface or subinterface for management traffic only.

In single mode, you can only use two data interfaces (and the dedicated management interface, if available) even if your security appliance includes more than two interfaces.

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Note

In transparent firewall mode, the management interface updates the MAC address table in the same manner as a data interface; therefore you should not connect both a management and a data interface to the same switch unless you configure one of the switch ports as a routed port (by default Cisco Catalyst switches share a MAC address for all VLAN switch ports). Otherwise, if traffic arrives on the management interface from the physically-connected switch, then the adaptive security appliance updates the MAC address table to use the

management

interface to access the switch, instead of the data interface. This action causes a temporary traffic interruption; the adaptive security appliance will not re-update the MAC address table for packets from the switch to the data interface for at least

30 seconds for security reasons.

•

•

•

•

Each directly connected network must be on the same subnet.

Do not specify the adaptive security appliance management IP address as the default gateway for connected devices; devices need to specify the router on the other side of the adaptive security appliance as the default gateway.

For multiple context mode, each context must use different interfaces; you cannot share an interface across contexts.

For multiple context mode, each context typically uses a different subnet. You can use overlapping subnets, but your network topology requires router and NAT configuration to make it possible from a routing standpoint.

IPv6 Guidelines

Supports IPv6.


•

When you change modes, the adaptive security appliance clears the running configuration because many commands are not supported for both modes. The startup configuration remains unchanged.

If you reload without saving, then the startup configuration is loaded, and the mode reverts back to the original setting. See the

“Setting the Firewall Mode” section on page 5-7 for information about

backing up your configuration file.

•

If you download a text configuration to the adaptive security appliance that changes the mode with the

firewall transparent

command, be sure to put the command at the top of the configuration; the adaptive security appliance changes the mode as soon as it reads the command and then continues reading the configuration you downloaded. If the command appears later in the configuration, the adaptive security appliance clears all the preceding lines in the configuration.

Unsupported Features in Transparent Mode

Table 5-1 lists the features are not supported in transparent mode.

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Table 5-1 Unsupported Features in Transparent Mode

Feature

Dynamic DNS

DHCP relay

Dynamic routing protocols

Multicast IP routing

QoS

VPN termination for through traffic

Description

—

The transparent firewall can act as a DHCP server, but it does not support the DHCP relay commands. DHCP relay is not required because you can allow DHCP traffic to pass through using two extended access lists: one that allows DCHP requests from the inside interface to the outside, and one that allows the replies from the server in the other direction.

You can, however, add static routes for traffic originating on the adaptive security appliance. You can also allow dynamic routing protocols through the adaptive security appliance using an extended access list.

You can allow multicast traffic through the adaptive security appliance by allowing it in an extended access list.

—

The transparent firewall supports site-to-site VPN tunnels for management connections only. It does not terminate VPN connections for traffic through the adaptive security appliance. You can pass VPN traffic through the security appliance using an extended access list, but it does not terminate non-management connections. SSL VPN is also not supported.

Setting the Firewall Mode

This section describes how to change the firewall mode using the CLI. You cannot change the mode in

ASDM.

Prerequisites

Note

We recommend that you set the firewall mode before you perform any other configuration because changing the firewall mode clears the running configuration.

When you change modes, the adaptive security appliance clears the running configuration (see the

“Guidelines and Limitations” section on page 5-5 for more information).

•

•

If you already have a populated configuration, be sure to back up your configuration before changing the mode; you can use this backup for reference when creating your new configuration.

Use the CLI at the console port to change the mode. If you use any other type of session, including the ASDM Command Line Interface tool or SSH, you will be disconnected when the configuration is cleared, and you will have to reconnect to the adaptive security appliance using the console port in any case.

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5-7


Configuring ARP Inspection for the Transparent Firewall


This section describes ARP inspection and how to enable it and includes the following topics:

•

Information About ARP Inspection, page 5-8

•

•

•

•

•

Licensing Requirements for ARP Inspection, page 5-8



Configuring ARP Inspection, page 5-9

Feature History for ARP Inspection, page 5-11

Information About ARP Inspection

By default, all ARP packets are allowed through the adaptive security appliance. You can control the flow of ARP packets by enabling ARP inspection.

When you enable ARP inspection, the adaptive security appliance compares the MAC address, IP address, and source interface in all ARP packets to static entries in the ARP table, and takes the following actions:

•

If the IP address, MAC address, and source interface match an ARP entry, the packet is passed through.

•

•

If there is a mismatch between the MAC address, the IP address, or the interface, then the adaptive security appliance drops the packet.

If the ARP packet does not match any entries in the static ARP table, then you can set the adaptive security appliance to either forward the packet out all interfaces (flood), or to drop the packet.

Note

The dedicated management interface, if present, never floods packets even if this parameter is set to flood.

ARP inspection prevents malicious users from impersonating other hosts or routers (known as ARP spoofing). ARP spoofing can enable a “man-in-the-middle” attack. For example, a host sends an

ARP request to the gateway router; the gateway router responds with the gateway router MAC address.

The attacker, however, sends another ARP response to the host with the attacker MAC address instead of the router MAC address. The attacker can now intercept all the host traffic before forwarding it on to the router.

ARP inspection ensures that an attacker cannot send an ARP response with the attacker MAC address, so long as the correct MAC address and the associated IP address are in the static ARP table.

Licensing Requirements for ARP Inspection


Model

All models


Base License.

5-8


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By default, all ARP packets are allowed through the adaptive security appliance.

If you enable ARP inspection, the default setting is to flood non-matching packets.



•

Supported in single and multiple context mode.

•

In multiple context mode, configure ARP inspection within each context.


Supported only in transparent firewall mode. Routed mode is not supported.

Configuring ARP Inspection

This section describes how to configure ARP inspection and includes the following topics:

•

•

•

Task Flow for Configuring ARP Inspection, page 5-9

Adding a Static ARP Entry, page 5-9

Enabling ARP Inspection, page 5-10

Task Flow for Configuring ARP Inspection

To configure ARP Inspection, perform the following steps:

Step 1

Step 2

Add static ARP entries according to the

“Adding a Static ARP Entry” section on page 5-9

. ARP inspection compares ARP packets with static ARP entries in the ARP table, so static ARP entries are required for this feature.

Enable ARP inspection according to the

“Enabling ARP Inspection” section on page 5-10

.

Adding a Static ARP Entry

ARP inspection compares ARP packets with static ARP entries in the ARP table. Although hosts identify a packet destination by an IP address, the actual delivery of the packet on Ethernet relies on the Ethernet

MAC address. When a router or host wants to deliver a packet on a directly connected network, it sends an ARP request asking for the MAC address associated with the IP address, and then delivers the packet to the MAC address according to the ARP response. The host or router keeps an ARP table so it does not have to send ARP requests for every packet it needs to deliver. The ARP table is dynamically updated whenever ARP responses are sent on the network, and if an entry is not used for a period of time, it times out. If an entry is incorrect (for example, the MAC address changes for a given IP address), the entry times out before it can be updated.

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5-9



Detailed Steps

Note

The transparent firewall uses dynamic ARP entries in the ARP table for traffic to and from the adaptive security appliance, such as management traffic.

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Choose the

Configuration > Device Setup > ARP > ARP Static Table

pane.

(Optional) To set the ARP timeout for

dynamic

ARP entries, enter a value in the ARP Timeout field.

This field sets the amount of time before the adaptive security appliance rebuilds the ARP table, between

60 to 4294967 seconds. The default is 14400 seconds. Rebuilding the ARP table automatically updates new host information and removes old host information. You might want to reduce the timeout because the host information changes frequently.

Click

Add

.

The Add ARP Static Configuration dialog box appears.

From the Interface drop-down list, choose the interface attached to the host network.

In the IP Address field, enter the IP address of the host.

In the MAC Address field, enter the MAC address of the host; for example, 00e0.1e4e.3d8b.

To perform proxy ARP for this address, check the

Proxy ARP

check box.

If the adaptive security appliance receives an ARP request for the specified IP address, then it responds with the specified MAC address.

Click

OK

, and then

Apply

.

What to Do Next

Enable ARP inspection according to the

“Enabling ARP Inspection” section on page 5-10 .

Enabling ARP Inspection

This section describes how to enable ARP inspection.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Choose the

Configuration > Device Setup > ARP > ARP Inspection

pane.

Choose the interface row on which you want to enable ARP inspection, and click

Edit

.

The Edit ARP Inspection dialog box appears.

To enable ARP inspection, check the

Enable ARP Inspection

check box.

(Optional) To flood non-matching ARP packets, check the

Flood ARP Packets

check box.

By default, packets that do not match any element of a static ARP entry are flooded out all interfaces except the originating interface. If there is a mismatch between the MAC address, the IP address, or the interface, then the adaptive security appliance drops the packet.

If you uncheck this check box, all non-matching packets are dropped, which restricts ARP through the adaptive security appliance to only static entries.

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Customizing the MAC Address Table for the Transparent Firewall

Step 5

Note

The Management 0/0 or 0/1 interface or subinterface, if present, never floods packets even if this parameter is set to flood.

Click

OK

, and then

Apply

.

Feature History for ARP Inspection

Table 5-2


Table 5-2

Feature Name

ARP inspection

Feature History for ARP Inspection

Releases

7.0(1)


ARP inspection compares the MAC address, IP address, and source interface in all ARP packets to static entries in the

ARP table.

The following commands were introduced:

arp

,

arp-inspection

, and

show arp-inspection

.

Customizing the MAC Address Table for the Transparent

Firewall

This section describes the MAC address table and includes the following topics:

•

•

•

Information About the MAC Address Table, page 5-11

Licensing Requirements for the MAC Address Table, page 5-12


•

•

•


Configuring the MAC Address Table, page 5-13

Feature History for the MAC Address Table, page 5-14

Information About the MAC Address Table

The adaptive security appliance learns and builds a MAC address table in a similar way as a normal bridge or switch: when a device sends a packet through the adaptive security appliance, the adaptive security appliance adds the MAC address to its table. The table associates the MAC address with the source interface so that the adaptive security appliance knows to send any packets addressed to the device out the correct interface.

The ASA 5505 adaptive security appliance includes a built-in switch; the switch MAC address table maintains the MAC address-to-switch port mapping for traffic within each VLAN. This section discusses the bridge MAC address table, which maintains the MAC address-to-VLAN interface mapping for traffic that passes between VLANs.

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5-11



Because the adaptive security appliance is a firewall, if the destination MAC address of a packet is not in the table, the adaptive security appliance does not flood the original packet on all interfaces as a normal bridge does. Instead, it generates the following packets for directly connected devices or for remote devices:

•

•

Packets for directly connected devices—The adaptive security appliance generates an ARP request for the destination IP address, so that the adaptive security appliance can learn which interface receives the ARP response.

Packets for remote devices—The adaptive security appliance generates a ping to the destination IP address so that the adaptive security appliance can learn which interface receives the ping reply.

The original packet is dropped.

Licensing Requirements for the MAC Address Table


Model

All models


Base License.


The default timeout value for dynamic MAC address table entries is 5 minutes.

By default, each interface, including the optional management interface, automatically learns the MAC addresses of entering traffic, and the adaptive security appliance adds corresponding entries to the MAC address table.



•


•

In multiple context mode, configure the MAC address table within each context.


Supported only in transparent firewall mode. Routed mode is not supported.

Additional Guidelines


management

interface to access the switch, instead of the data interface. This action causes a temporary traffic interruption; the adaptive security appliance will not re-update the MAC address table for packets from the switch to the data interface for at least 30 seconds for security reasons.

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Configuring the MAC Address Table

This section describes how you can customize the MAC address table and includes the following sections:

•

Adding a Static MAC Address, page 5-13

•

Disabling MAC Address Learning, page 5-13

Adding a Static MAC Address

Normally, MAC addresses are added to the MAC address table dynamically as traffic from a particular

MAC address enters an interface. You can add static MAC addresses to the MAC address table if desired.

One benefit to adding static entries is to guard against MAC spoofing. If a client with the same

MAC address as a static entry attempts to send traffic to an interface that does not match the static entry, then the adaptive security appliance drops the traffic and generates a system message. When you add a static ARP entry (see the

“Adding a Static ARP Entry” section on page 5-9 ), a static MAC address entry

is automatically added to the MAC address table.

To add a static MAC address to the MAC address table, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Choose the

Configuration > Device Setup > Bridging > MAC Address Table

pane.

(Optional) To set the time a MAC address entry stays in the MAC address table before timing out, enter a value in the Dynamic Entry Timeout field.

This value is between 5 and 720 minutes (12 hours). 5 minutes is the default.

Click

Add

.

The Add MAC Address Entry dialog box appears.

From the Interface Name drop-down list, choose the source interface associated with the MAC address.

In the MAC Address field, enter the MAC address.

Click

OK

, and then

Apply

.

Disabling MAC Address Learning

By default, each interface automatically learns the MAC addresses of entering traffic, and the adaptive security appliance adds corresponding entries to the MAC address table. You can disable MAC address learning if desired, however, unless you statically add MAC addresses to the table, no traffic can pass through the adaptive security appliance.

To disable MAC address learning, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Choose the

Configuration > Device Setup > Bridging > MAC Learning

pane.

To disable MAC learning, choose an interface row, and click

Disable

.

To reenable MAC learning, click

Enable

.

Click

Apply

.

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5-13


Firewall Mode Examples

Feature History for the MAC Address Table

Table 5-3

Table 5-3 lists the release history for this feature.

Feature History for the MAC Address Table

Feature Name

MAC address table

Releases

7.0(1)


Transparent firewall mode uses a MAC address table.


This section includes examples of how traffic moves through the adaptive security appliance and includes the following topics:

•

•

How Data Moves Through the Security Appliance in Routed Firewall Mode, page 5-14

How Data Moves Through the Transparent Firewall, page 5-20

How Data Moves Through the Security Appliance in Routed Firewall Mode

This section describes how data moves through the adaptive security appliance in routed firewall mode and includes the following topics:

•

An Inside User Visits a Web Server, page 5-15

•

•

•

•

An Outside User Visits a Web Server on the DMZ, page 5-16

An Inside User Visits a Web Server on the DMZ, page 5-17

An Outside User Attempts to Access an Inside Host, page 5-18

A DMZ User Attempts to Access an Inside Host, page 5-19

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An Inside User Visits a Web Server

Figure 5-2 shows an inside user accessing an outside web server.

Figure 5-2 Inside to Outside

www.example.com

Outside


209.165.201.2

Source Addr Translation

10.1.2.27

209.165.201.10

10.1.2.1

10.1.1.1

Inside DMZ

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User

10.1.2.27

Web Server

10.1.1.3

The following steps describe how data moves through the adaptive security appliance (see

Figure 5-2 ):

1.

2.

The user on the inside network requests a web page from www.example.com.

The adaptive security appliance receives the packet and because it is a new session, the adaptive security appliance verifies that the packet is allowed according to the terms of the security policy

(access lists, filters, AAA).

3.

4.

For multiple context mode, the adaptive security appliance first classifies the packet according to either a unique interface or a unique destination address associated with a context; the destination address is associated by matching an address translation in a context. In this case, the interface would be unique; the www.example.com IP address does not have a current address translation in a context.

The adaptive security appliance translates the local source address (10.1.2.27) to the global address

209.165.201.10, which is on the outside interface subnet.

The global address could be on any subnet, but routing is simplified when it is on the outside interface subnet.

The adaptive security appliance then records that a session is established and forwards the packet from the outside interface.


5-15



5.

6.

When www.example.com responds to the request, the packet goes through the adaptive security appliance, and because the session is already established, the packet bypasses the many lookups associated with a new connection. The adaptive security appliance performs NAT by translating the global destination address to the local user address, 10.1.2.27.

The adaptive security appliance forwards the packet to the inside user.

An Outside User Visits a Web Server on the DMZ

Figure 5-3

shows an outside user accessing the DMZ web server.

Figure 5-3 Outside to DMZ

User

Outside

10.1.2.1

209.165.201.2

Dest Addr Translation

209.165.201.

3 10.1.1.1

3

10.1.1.1

Inside

DMZ

5-16

Web Server

10.1.1.

3


Figure 5-3

):

1.

2.

A user on the outside network requests a web page from the DMZ web server using the global destination address of 209.165.201.3, which is on the outside interface subnet.



3.

For multiple context mode, the adaptive security appliance first classifies the packet according to either a unique interface or a unique destination address associated with a context; the destination address is associated by matching an address translation in a context. In this case, the classifier

“knows” that the DMZ web server address belongs to a certain context because of the server address translation.

The adaptive security appliance translates the destination address to the local address 10.1.1.3.


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4.

5.

6.

The adaptive security appliance then adds a session entry to the fast path and forwards the packet from the DMZ interface.

When the DMZ web server responds to the request, the packet goes through the adaptive security appliance and because the session is already established, the packet bypasses the many lookups associated with a new connection. The adaptive security appliance performs NAT by translating the local source address to 209.165.201.3.

The adaptive security appliance forwards the packet to the outside user.

An Inside User Visits a Web Server on the DMZ

Figure 5-4 shows an inside user accessing the DMZ web server.

Figure 5-4 Inside to DMZ

Outside

209.165.201.2

10.1.2.1

10.1.1.1

Inside DMZ

User

10.1.2.27

Web Server

10.1.1.3

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Figure 5-4 ):

1.

A user on the inside network requests a web page from the DMZ web server using the destination address of 10.1.1.3.

2.



For multiple context mode, the adaptive security appliance first classifies the packet according to either a unique interface or a unique destination address associated with a context; the destination address is associated by matching an address translation in a context. In this case, the interface is unique; the web server IP address does not have a current address translation.


5-17



3.

4.

5.

The adaptive security appliance then records that a session is established and forwards the packet out of the DMZ interface.

When the DMZ web server responds to the request, the packet goes through the fast path, which lets the packet bypass the many lookups associated with a new connection.


An Outside User Attempts to Access an Inside Host

Figure 5-5

shows an outside user attempting to access the inside network.

Figure 5-5 Outside to Inside

www.example.com

Outside

209.165.201.2

Inside

10.1.2.1

10.1.1.1

DMZ

User

10.1.2.27


Figure 5-5

):

1.

A user on the outside network attempts to reach an inside host (assuming the host has a routable

IP address).

If the inside network uses private addresses, no outside user can reach the inside network without

NAT. The outside user might attempt to reach an inside user by using an existing NAT session.

2.

3.

The adaptive security appliance receives the packet and because it is a new session, the adaptive security appliance verifies if the packet is allowed according to the security policy (access lists, filters, AAA).

The packet is denied, and the adaptive security appliance drops the packet and logs the connection attempt.

5-18


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If the outside user is attempting to attack the inside network, the adaptive security appliance employs many technologies to determine if a packet is valid for an already established session.

A DMZ User Attempts to Access an Inside Host

Figure 5-6 shows a user in the DMZ attempting to access the inside network.

Figure 5-6 DMZ to Inside

Outside

Inside

209.165.201.2

10.1.2.1

10.1.1.1

DMZ

User

10.1.2.27

Web Server

10.1.1.3


Figure 5-6 ):

1.

2.

A user on the DMZ network attempts to reach an inside host. Because the DMZ does not have to route the traffic on the Internet, the private addressing scheme does not prevent routing.

The adaptive security appliance receives the packet and because it is a new session, the adaptive security appliance verifies if the packet is allowed according to the security policy (access lists, filters, AAA).

The packet is denied, and the adaptive security appliance drops the packet and logs the connection attempt.

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How Data Moves Through the Transparent Firewall

Figure 5-7

shows a typical transparent firewall implementation with an inside network that contains a public web server. The adaptive security appliance has an access list so that the inside users can access

Internet resources. Another access list lets the outside users access only the web server on the inside network.

Figure 5-7 Typical Transparent Firewall Data Path

www.example.com

Internet

209.165.201.2

Management IP

209.165.201.6

209.165.200.230

Host

209.165.201.3

Web Server

209.165.200.225

This section describes how data moves through the adaptive security appliance and includes the following topics:

•

•

•

•

An Inside User Visits a Web Server, page 5-21

An Inside User Visits a Web Server Using NAT, page 5-22

An Outside User Visits a Web Server on the Inside Network, page 5-23

An Outside User Attempts to Access an Inside Host, page 5-24

5-20


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An Inside User Visits a Web Server

Figure 5-8 shows an inside user accessing an outside web server.

Figure 5-8 Inside to Outside

www.example.com


Internet

209.165.201.2

Management IP

209.165.201.6

OL-20339-01

Host

209.165.201.3


Figure 5-8 ):

1.


2.

The adaptive security appliance receives the packet and adds the source MAC address to the MAC address table, if required. Because it is a new session, it verifies that the packet is allowed according to the terms of the security policy (access lists, filters, AAA).

For multiple context mode, the adaptive security appliance first classifies the packet according to a unique interface.

3.

4.

5.

6.

The adaptive security appliance records that a session is established.

If the destination MAC address is in its table, the adaptive security appliance forwards the packet out of the outside interface. The destination MAC address is that of the upstream router,

209.186.201.2.

If the destination MAC address is not in the adaptive security appliance table, the adaptive security appliance attempts to discover the MAC address by sending an ARP request and a ping. The first packet is dropped.

The web server responds to the request; because the session is already established, the packet bypasses the many lookups associated with a new connection.



5-21



An Inside User Visits a Web Server Using NAT

Figure 5-8

shows an inside user accessing an outside web server.

Figure 5-9 Inside to Outside with NAT

www.example.com

Internet

Static route on router to 209.165.201.0/27 through security appliance

Security appliance

10.1.2.1

Management IP

10.1.2.2


10.1.2.27

209.165.201.10

Host

10.1.2.27


Figure 5-8

):

1.


2.



3.

4.

5.

The adaptive security appliance translates the real address (10.1.2.27) to the mapped address

209.165.201.10.

Because the mapped address is not on the same network as the outside interface, then be sure the upstream router has a static route to the mapped network that points to the adaptive security appliance.

The adaptive security appliance then records that a session is established and forwards the packet from the outside interface.

If the destination MAC address is in its table, the adaptive security appliance forwards the packet out of the outside interface. The destination MAC address is that of the upstream router, 10.1.2.1.

5-22


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6.

7.



The adaptive security appliance performs NAT by translating the mapped address to the real address,

10.1.2.27.

An Outside User Visits a Web Server on the Inside Network

Figure 5-10 shows an outside user accessing the inside web server.


Host

Internet

209.165.201.2

Management IP

209.165.201.6

209.165.201.1

209.165.200.230

OL-20339-01

Web Server

209.165.200.225


Figure 5-10 ):

1.

2.

A user on the outside network requests a web page from the inside web server.




5-23



3.

4.

5.

6.

The adaptive security appliance records that a session is established.

If the destination MAC address is in its table, the adaptive security appliance forwards the packet out of the inside interface. The destination MAC address is that of the downstream router,

209.165.201.1.



The adaptive security appliance forwards the packet to the outside user.

An Outside User Attempts to Access an Inside Host

Figure 5-11

shows an outside user attempting to access a host on the inside network.


Host

Internet

209.165.201.2

Management IP

209.165.201.6

Host

209.165.201.3


Figure 5-11

):

1.

A user on the outside network attempts to reach an inside host.

2.

The adaptive security appliance receives the packet and adds the source MAC address to the MAC address table, if required. Because it is a new session, it verifies if the packet is allowed according to the terms of the security policy (access lists, filters, AAA).


5-24


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3.

4.

The packet is denied because there is no access list permitting the outside host, and the adaptive security appliance drops the packet.

If the outside user is attempting to attack the inside network, the adaptive security appliance employs many technologies to determine if a packet is valid for an already established session.

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5-26


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P

A R T

2

Setting up the Adaptive Security

Appliance

C H A P T E R

6

Configuring Multiple Context Mode

This chapter describes how to configure multiple security contexts on the adaptive security appliance and includes the following sections:

•

Information About Security Contexts, page 6-1

•

•

•

•

•

•

Licensing Requirements for Multiple Context Mode, page 6-12



Configuring Multiple Contexts, page 6-13

Monitoring Security Contexts, page 6-20

Feature History for Multiple Context Mode, page 6-23

Information About Security Contexts

You can partition a single adaptive security appliance into multiple virtual devices, known as security contexts. Each context is an independent device, with its own security policy, interfaces, and administrators. Multiple contexts are similar to having multiple standalone devices. Many features are supported in multiple context mode, including routing tables, firewall features, IPS, and management.

Some features are not supported, including VPN and dynamic routing protocols.

Note

When the adaptive security appliance is configured for security contexts (for example, for Active/Active

Stateful Failover), IPsec or SSL VPN cannot be enabled. Therefore, these features are unavailable.

This section provides an overview of security contexts and includes the following topics:

•

•

•

•

•

•

•

Common Uses for Security Contexts, page 6-2

Context Configuration Files, page 6-2

How the Security Appliance Classifies Packets, page 6-3

Cascading Security Contexts, page 6-6

Management Access to Security Contexts, page 6-7

Information About Resource Management, page 6-8

Information About MAC Addresses, page 6-11


6-1 OL-20339-01

Chapter 6 Configuring Multiple Context Mode


Common Uses for Security Contexts

You might want to use multiple security contexts in the following situations:

•

You are a service provider and want to sell security services to many customers. By enabling multiple security contexts on the adaptive security appliance, you can implement a cost-effective, space-saving solution that keeps all customer traffic separate and secure, and also eases configuration.

•

•

•

You are a large enterprise or a college campus and want to keep departments completely separate.

You are an enterprise that wants to provide distinct security policies to different departments.

You have any network that requires more than one adaptive security appliance.

Context Configuration Files

This section describes how the adaptive security appliance implements multiple context mode configurations and includes the following sections:

•

Context Configurations, page 6-2

•

•

System Configuration, page 6-2

Admin Context Configuration, page 6-2

Context Configurations

The adaptive security appliance includes a configuration for each context that identifies the security policy, interfaces, and almost all the options you can configure on a standalone device. You can store context configurations on the internal flash memory or the external flash memory card, or you can download them from a TFTP, FTP, or HTTP(S) server.

System Configuration

The system administrator adds and manages contexts by configuring each context configuration location, allocated interfaces, and other context operating parameters in the system configuration, which, like a single mode configuration, is the startup configuration. The system configuration identifies basic settings for the adaptive security appliance. The system configuration does not include any network interfaces or network settings for itself; rather, when the system needs to access network resources (such as downloading the contexts from the server), it uses one of the contexts that is designated as the

admin context

. The system configuration does include a specialized failover interface for failover traffic only.

Admin Context Configuration

The admin context is just like any other context, except that when a user logs in to the admin context, then that user has system administrator rights and can access the system and all other contexts. The admin context is not restricted in any way, and can be used as a regular context. However, because logging into the admin context grants you administrator privileges over all contexts, you might need to restrict access to the admin context to appropriate users. The admin context must reside on flash memory, and not remotely.

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If your system is already in multiple context mode, or if you convert from single mode, the admin context is created automatically as a file on the internal flash memory called admin.cfg. This context is named

“admin.” If you do not want to use admin.cfg as the admin context, you can change the admin context.

How the Security Appliance Classifies Packets

Each packet that enters the adaptive security appliance must be classified, so that the adaptive security appliance can determine to which context to send a packet. This section includes the following topics:

•

Valid Classifier Criteria, page 6-3

•

Classification Examples, page 6-4

Note

If the destination MAC address is a multicast or broadcast MAC address, the packet is duplicated and delivered to each context.

Valid Classifier Criteria

This section describes the criteria used by the classifier and includes the following topics:

•

•

•

Unique Interfaces, page 6-3

Unique MAC Addresses, page 6-3

NAT Configuration, page 6-3

Note

For management traffic destined for an interface, the interface IP address is used for classification.

The routing table is not used for packet classification.

Unique Interfaces

Unique MAC Addresses

If multiple contexts share an interface, then the classifier uses the interface MAC address. The adaptive security appliance lets you assign a different MAC address in each context to the same shared interface, whether it is a shared physical interface or a shared subinterface. By default, shared interfaces do not have unique MAC addresses; the interface uses the physical interface burned-in MAC address in every context. An upstream router cannot route directly to a context without unique MAC addresses. You can set the MAC addresses manually when you configure each interface (see the

“Configuring Advanced

Interface Parameters” section on page 8-26

), or you can automatically generate MAC addresses (see the

“Automatically Assigning MAC Addresses to Context Interfaces” section on page 6-19

).

NAT Configuration

If only one context is associated with the ingress interface, the adaptive security appliance classifies the packet into that context. In transparent firewall mode, unique interfaces for contexts are required, so this method is used to classify packets at all times.

If you do not use unique MAC addresses, then the mapped addresses in your NAT configuration are used to classify packets. We recommend using MAC addresses instead of NAT, so that traffic classification can occur regardless of the completeness of the NAT configuration.


OL-20339-01 6-3



Classification Examples

Figure 6-1

shows multiple contexts sharing an outside interface. The classifier assigns the packet to

Context B because Context B includes the MAC address to which the router sends the packet.

Figure 6-1 Packet Classification with a Shared Interface using MAC Addresses

Internet

Packet Destination:

209.165.201.1 via MAC 000C.F142.4CDC

GE 0/0.1 (Shared Interface)

Classifier

MAC 000C.F142.4CDC

Admin

Context

MAC 000C.F142.4CDA

Context A

MAC 000C.F142.4CDB

Context B

GE 0/1.1

Admin

Network

GE 0/1.2

Inside

Customer A

GE 0/1.3

Inside

Customer B

Host

209.165.202.129

Host

209.165.200.225

Host

209.165.201.1

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Note that all new incoming traffic must be classified, even from inside networks. Figure 6-2

shows a host on the Context B inside network accessing the Internet. The classifier assigns the packet to Context B because the ingress interface is Gigabit Ethernet 0/1.3, which is assigned to Context B.

Figure 6-2 Incoming Traffic from Inside Networks

Internet

Admin

Context

Context A

GE 0/0.1

Context B

Classifier

GE 0/1.1

Admin

Network

GE 0/1.2

Inside

Customer A

GE 0/1.3

Inside

Customer B

Host

10.1.1.13

Host

10.1.1.13

Host

10.1.1.13

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6-5



For transparent firewalls, you must use unique interfaces.

Figure 6-3 shows a host on the Context B

inside network accessing the Internet. The classifier assigns the packet to Context B because the ingress interface is Gigabit Ethernet 1/0.3, which is assigned to Context B.

Figure 6-3 Transparent Firewall Contexts

Internet

Classifier

Admin

Context

GE 0/0.2

GE 0/0.1

Context A

GE 0/0.3

Context B

GE 1/0.1

Admin

Network

GE 1/0.2

Inside

Customer A

GE 1/0.3

Inside

Customer B

Host

10.1.1.13

Host

10.1.2.13

Host

10.1.3.13

Cascading Security Contexts

Placing a context directly in front of another context is called cascading contexts; the outside interface of one context is the same interface as the inside interface of another context. You might want to cascade contexts if you want to simplify the configuration of some contexts by configuring shared parameters in the top context.

Note

Cascading contexts requires that you configure unique MAC addresses for each context interface.

Because of the limitations of classifying packets on shared interfaces without MAC addresses, we do not recommend using cascading contexts without unique MAC addresses.

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Figure 6-4 shows a gateway context with two contexts behind the gateway.

Figure 6-4 Cascading Contexts

Internet

GE 0/0.2

Outside

Gateway

Context

GE 0/0.1

(Shared Interface)

Inside

Outside Outside

Admin

Context

Context A

GE 1/1.8

Inside

GE 1/1.43

Inside

Management Access to Security Contexts

The adaptive security appliance provides system administrator access in multiple context mode as well as access for individual context administrators. The following sections describe logging in as a system administrator or as a context administrator:

•

•

System Administrator Access, page 6-7

Context Administrator Access, page 6-8

System Administrator Access

You can access the adaptive security appliance as a system administrator in two ways:

•

Access the adaptive security appliance console.

From the console, you access the

system execution space

, which means that any commands you enter affect only the system configuration or the running of the system (for run-time commands).

•

Access the admin context using Telnet, SSH, or ASDM.

See

Chapter 32, “Configuring Management Access,” to enable Telnet, SSH, and SDM access.

As the system administrator, you can access all contexts.

When you change to a context from admin or the system, your username changes to the default

“enable_15” username. If you configured command authorization in that context, you need to either configure authorization privileges for the “enable_15” user, or you can log in as a different name for which you provide sufficient privileges in the command authorization configuration for the context. To


OL-20339-01 6-7



log in with a username, enter the

login

command. For example, you log in to the admin context with the username “admin.” The admin context does not have any command authorization configuration, but all other contexts include command authorization. For convenience, each context configuration includes a user “admin” with maximum privileges. When you change from the admin context to context A, your username is altered, so you must log in again as “admin” by entering the

login

command. When you change to context B, you must again enter the

login

command to log in as “admin.”

The system execution space does not support any AAA commands, but you can configure its own enable password, as well as usernames in the local database to provide individual logins.

Context Administrator Access

You can access a context using Telnet, SSH, or ASDM. If you log in to a non-admin context, you can only access the configuration for that context. You can provide individual logins to the context. See

Chapter 32, “Configuring Management Access,” to enable Telnet, SSH, and SDM access and to

configure management authentication.

Information About Resource Management

By default, all security contexts have unlimited access to the resources of the adaptive security appliance, except where maximum limits per context are enforced. However, if you find that one or more contexts use too many resources, and they cause other contexts to be denied connections, for example, then you can configure resource management to limit the use of resources per context.

The adaptive security appliance manages resources by assigning contexts to resource classes. Each context uses the resource limits set by the class.


•

Resource Limits, page 6-8

•

•

Default Class, page 6-9

Class Members, page 6-10

Resource Limits

When you create a class, the adaptive security appliance does not set aside a portion of the resources for each context assigned to the class; rather, the adaptive security appliance sets the maximum limit for a context. If you oversubscribe resources, or allow some resources to be unlimited, a few contexts can “use up” those resources, potentially affecting service to other contexts.

You can set the limit for individual resources, as a percentage (if there is a hard system limit) or as an absolute value.

You can oversubscribe the adaptive security appliance by assigning more than 100 percent of a resource across all contexts. For example, you can set the Bronze class to limit connections to 20 percent per context, and then assign 10 contexts to the class for a total of 200 percent. If contexts concurrently use more than the system limit, then each context gets less than the 20 percent you intended. (See

Figure 6-5

.)

6-8


OL-20339-01



Figure 6-5 Resource Oversubscription

Total Number of System Connections = 999,900

Max. 20%

(199,800)

16%

(159,984)

12%

(119,988)

8%

(79,992)

4%

(39,996)

Maximum connections allowed.

Connections in use.

Connections denied because system limit was reached.

1 2 3 4 5 6

Contexts in Class

7 8 9 10

If you assign an absolute value to a resource across all contexts that exceeds the practical limit of the adaptive security appliance, then the performance of the adaptive security appliance might be impaired.

The adaptive security appliance lets you assign unlimited access to one or more resources in a class, instead of a percentage or absolute number. When a resource is unlimited, contexts can use as much of the resource as the system has available or that is practically available. For example, Context A, B, and

C are in the Silver Class, which limits each class member to 1 percent of the connections, for a total of

3 percent; but the three contexts are currently only using 2 percent combined. Gold Class has unlimited access to connections. The contexts in the Gold Class can use more than the 97 percent of “unassigned” connections; they can also use the 1 percent of connections not currently in use by Context A, B, and C, even if that means that Context A, B, and C are unable to reach their 3 percent combined limit. (See

Figure 6-6 .) Setting unlimited access is similar to oversubscribing the adaptive security appliance,

except that you have less control over how much you oversubscribe the system.

Figure 6-6 Unlimited Resources

50% 43%

5%

4%

3%

2%

1%

Maximum connections allowed.

Connections in use.

Connections denied because system limit was reached.

A B C

Contexts Silver Class

1 2 3

Contexts Gold Class

Default Class

All contexts belong to the default class if they are not assigned to another class; you do not have to actively assign a context to the default class.

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6-9



If a context belongs to a class other than the default class, those class settings always override the default class settings. However, if the other class has any settings that are not defined, then the member context uses the default class for those limits. For example, if you create a class with a 2 percent limit for all concurrent connections, but no other limits, then all other limits are inherited from the default class.

Conversely, if you create a class with a limit for all resources, the class uses no settings from the default class.

By default, the default class provides unlimited access to resources for all contexts, except for the following limits, which are by default set to the maximum allowed per context:

•

Telnet sessions—5 sessions.

•

•

SSH sessions—5 sessions.

IPsec sessions—5 sessions.

•

MAC addresses—65,535 entries.

Figure 6-7

shows the relationship between the default class and other classes. Contexts A and C belong to classes with some limits set; other limits are inherited from the default class. Context B inherits no limits from default because all limits are set in its class, the Gold class. Context D was not assigned to a class, and is by default a member of the default class.

Figure 6-7 Resource Classes

Class

Bronze

(Some

Limits

Set)

Context A

Default Class

Class Gold

(All Limits

Set)

Class Silver

(Some Limits

Set)

Context C

Context D

Context B

Class Members

To use the settings of a class, assign the context to the class when you define the context. All contexts belong to the default class if they are not assigned to another class; you do not have to actively assign a context to default. You can only assign a context to one resource class. The exception to this rule is that limits that are undefined in the member class are inherited from the default class; so in effect, a context could be a member of default plus another class.

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Information About MAC Addresses

To allow contexts to share interfaces, we suggest that you assign unique MAC addresses to each shared context interface (see the


).

The MAC address is used to classify packets within a context. If you share an interface, but do not have unique MAC addresses for the interface in each context, then the destination IP address is used to classify packets. The destination address is matched with the context NAT configuration, and this method has some limitations compared to the MAC address method. See the

“How the Security

Appliance Classifies Packets” section on page 6-3 for information about classifying packets.

In the rare circumstance that the generated MAC address conflicts with another private MAC address in your network, you can manually set the MAC address for the interface within the context. See the

“Configuring Advanced Interface Parameters” section on page 8-26 to manually set the MAC address.


•

•

•

•

Default MAC Address, page 6-11

Interaction with Manual MAC Addresses, page 6-11

Failover MAC Addresses, page 6-11

MAC Address Format, page 6-11

Default MAC Address

By default, the physical interface uses the burned-in MAC address, and all subinterfaces of a physical interface use the same burned-in MAC address.

All auto-generated MAC addresses start with A2. The auto-generated MAC addresses are persistent across reloads.

Interaction with Manual MAC Addresses

If you manually assign a MAC address and also enable auto-generation, then the manually assigned

MAC address is used. If you later remove the manual MAC address, the auto-generated address is used.

Because auto-generated addresses start with A2, you cannot start manual MAC addresses with A2 if you also want to use auto-generation.

Failover MAC Addresses

For use with failover, the adaptive security appliance generates both an active and standby MAC address for each interface. If the active unit fails over and the standby unit becomes active, the new active unit starts using the active MAC addresses to minimize network disruption. See the

“MAC Address Format”

section for more information.

For upgrading failover units with the legacy version of the

mac-address auto

command before the

prefix

keyword was introduced, see the


command in the


Command Reference

.

MAC Address Format

The adaptive security appliance generates the MAC address using the following format:

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6-11


Licensing Requirements for Multiple Context Mode

A2

xx.yyzz.zzzz

Where

xx.yy

is a user-defined prefix, and

zz.zzzz

is an internal counter generated by the adaptive security appliance. For the standby MAC address, the address is identical except that the internal counter is increased by 1.

For an example of how the prefix is used, if you set a prefix of 77, then the adaptive security appliance converts 77 into the hexadecimal value 004D (

yyxx

). When used in the MAC address, the prefix is reversed (

xxyy

) to match the adaptive security appliance native form:

A2

4D.00

zz.zzzz

For a prefix of 1009 (03F1), the MAC address is:

A2

F1.03

zz.zzzz

Licensing Requirements for Multiple Context Mode

Model

ASA 5505

ASA 5510


No support.

Security Plus License: 2 contexts.

Optional license: 5 contexts.

ASA 5520 Base License: 2 contexts.

Optional licenses: 5, 10, or 20 contexts.

ASA 5540, 5550, and

5580

Base License: 2 contexts.

Optional licenses: 5, 10, 20, or 50 contexts.




Supported in routed and transparent firewall mode.


Active/Active mode failover is only supported in multiple context mode.

IPv6 Guidelines

Supports IPv6.

Model Guidelines

Does not support the ASA 5505.

Unsupported Features

Multiple context mode does not support the following features:

6-12


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•

•

•

•

•

•

Dynamic routing protocols

Security contexts support only static routes. You cannot enable OSPF, RIP, or EIGRP in multiple context mode.

VPN

Multicast routing. Multicast bridging is supported.

Threat Detection

Phone Proxy

QoS


The context mode (single or multiple) is not stored in the configuration file, even though it does endure reboots. If you need to copy your configuration to another device, set the mode on the new device to match.


By default, the adaptive security appliance is in single context mode.

Configuring Multiple Contexts

This section describes how to configure multiple context mode, and includes the following topics:

•

•

•

•

Task Flow for Configuring Multiple Context Mode, page 6-13

Enabling or Disabling Multiple Context Mode, page 6-14

Configuring a Class for Resource Management, page 6-15

Configuring a Security Context, page 6-17

•

Automatically Assigning MAC Addresses to Context Interfaces, page 6-19

Task Flow for Configuring Multiple Context Mode

To configure multiple context mode, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Enable multiple context mode. See the “Enabling or Disabling Multiple Context Mode” section on page 6-14

.

(Optional) Configure classes for resource management. See the

“Configuring a Class for Resource

Management” section on page 6-15 .

Configure security contexts. See the

“Configuring a Security Context” section on page 6-17 .

(Optional) Automatically assign MAC addresses to context interfaces. See the

“Automatically Assigning

MAC Addresses to Context Interfaces” section on page 6-19 .

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6-13



Enabling or Disabling Multiple Context Mode

Your adaptive security appliance might already be configured for multiple security contexts depending on how you ordered it from Cisco. If you are upgrading, however, you might need to convert from single mode to multiple mode by following the procedures in this section.

ASDM supports changing modes from single to multiple mode if you use the High Availability and

Scalability Wizard and you enable Active/Active failover. See

Chapter 58, “Using the High Availability and Scalability Wizard,”

for more information. If you do not want to use Active/Active failover or want to change back to single mode, you must change modes at the CLI. This section describes changing modes at the CLI.


•

Enabling Multiple Context Mode, page 6-14

•

Restoring Single Context Mode, page 6-14

Enabling Multiple Context Mode

When you convert from single mode to multiple mode, the adaptive security appliance converts the running configuration into two files: a new startup configuration that comprises the system configuration, and admin.cfg that comprises the admin context (in the root directory of the internal flash memory). The original running configuration is saved as old_running.cfg (in the root directory of the internal flash memory). The original startup configuration is not saved. The adaptive security appliance automatically adds an entry for the admin context to the system configuration with the name “admin.”

Prerequisites

•

•

When you convert from single mode to multiple mode, the adaptive security appliance converts the running configuration into two files. The original startup configuration is not saved, so if it differs from the running configuration, you should back it up before proceeding.

The context mode (single or multiple) is not stored in the configuration file, even though it does endure reboots. If you need to copy your configuration to another device, set the mode on the new device to match.

Detailed Steps

Command mode multiple

Purpose

Changes to multiple context mode. You are prompted to reboot the adaptive security appliance.

Example:

hostname(config)# mode multiple

Restoring Single Context Mode

To copy the old running configuration to the startup configuration and to change the mode to single mode, perform the following steps.

6-14


OL-20339-01



Prerequisites

Perform this procedure in the system execution space.

Detailed Steps

Command

Step 1 copy flash:old_running.cfg startup-config

Purpose

Copies the backup version of your original running configuration to the current startup configuration.

Example:

hostname(config)# copy flash:old_running.cfg startup-config

Step 2 mode single

Sets the mode to single mode. You are prompted to reboot the adaptive security appliance.

Example:

hostname(config)# mode single

Configuring a Class for Resource Management

To configure a class in the system configuration, perform the following steps. You can change the value of a particular resource limit by reentering the command with a new value.

Prerequisites


Guidelines

Table 6-1

lists the resource types and the limits.

Resource Names and Limits Table 6-1

Resource Name

Rate or

Concurrent

Minimum and

Maximum Number per Context mac-addresses

Concurrent N/A

conns inspects

Concurrent or Rate

Rate

N/A

N/A

System Limit

1

Description

65,535

Concurrent connections:

See the “Supported

Feature Licenses Per

Model” section on page 4-1 for the

connection limit for your platform.

For transparent firewall mode, the number of

MAC addresses allowed in the MAC address table.

TCP or UDP connections between any two hosts, including connections between one host and multiple other hosts.

Rate: N/A

N/A Application inspections.

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6-15



Table 6-1 Resource Names and Limits (continued)

Resource Name hosts asdm

Rate or

Concurrent

Concurrent N/A

Concurrent

Minimum and

Maximum Number per Context

1 minimum

5 maximum

System Limit

1

N/A

32

Description

Hosts that can connect through the adaptive security appliance.

ASDM management sessions.

Note

ASDM sessions use two HTTPS connections: one for monitoring that is always present, and one for making configuration changes that is present only when you make changes. For example, the system limit of 32

ASDM sessions represents a limit of

64 HTTPS sessions.

SSH sessions.

ssh syslogs telnet

Concurrent 1 minimum

Rate

Concurrent

5 maximum

N/A

1 minimum

100

N/A

100

System log messages.

Telnet sessions.

xlates

Concurrent

5 maximum

N/A N/A Address translations.

1.

If this column value is N/A, then you cannot set a percentage of the resource because there is no hard system limit for the resource.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

If you are not already in the System configuration mode, in the Device List pane, double-click

System

under the active device IP address.

On the Context Management > Resource Class pane, click

Add

.

The Add Resource Class dialog box appears.

In the Resource Class field, enter a class name up to 20 characters in length.

In the Count Limited Resources area, set the concurrent limits for resources.

For resources that do not have a system limit, you cannot set the percentage; you can only set an absolute value. If you do not set a limit, the limit is inherited from the default class. If the default class does not set a limit, then the resource is unlimited, or the system limit if available.

You can set one or more of the following limits:

•

Hosts—Sets the limit for concurrent hosts that can connect through the adaptive security appliance.

Select the check box to enable this limit. If you set the limit to 0, it is unlimited.

•

Telnet—Sets the limit for concurrent Telnet sessions. Select the check box to enable this limit. You can set the limit as a percentage by entering any integer greater than 1 and selecting

Percent

from the list. You can assign more than 100 percent if you want to oversubscribe the device. Or you can set the limit as an absolute value by entering an integer between 1 and 5 and selecting

Absolute

from the list. The system has a maximum of 100 sessions divided between all contexts.

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Step 5

Step 6

•

•

•

•

•

ASDM Sessions—Sets the limit for concurrent ASDM sessions. Select the check box to enable this limit. You can set the limit as a percentage by entering any integer greater than 1 and selecting

Percent

from the list. You can assign more than 100 percent if you want to oversubscribe the device.

Or you can set the limit as an absolute value by entering an integer between 1 and 5 and selecting

Absolute


ASDM sessions use two HTTPS connections: one for monitoring that is always present, and one for making configuration changes that is present only when you make changes. For example, the system limit of 32 ASDM sessions represents a limit of 64 HTTPS sessions, divided between all contexts.

Connections—Sets the limit for concurrent TCP or UDP connections between any two hosts, including connections between one host and multiple other hosts. Select the check box to enable this limit. You can set the limit as a percentage by entering any integer greater than 1 and selecting

Percent

from the list. You can assign more than 100 percent if you want to oversubscribe the device.

Or you can set the limit as an absolute value by entering an integer between 0 (system limit) and the system limit for your model, and selecting

Absolute

from the list. See the

Release Notes for

Cisco ASDM

for the connection limit for your model.

Xlates—Sets the limit for address translations. Select the check box to enable this limit. If you set the limit to 0, it is unlimited.

SSH—Sets the limit for SSH sessions. Select the check box to enable this limit. You can set the limit as a percentage by entering any integer greater than 1 and selecting

Percent

from the list. You can assign more than 100 percent if you want to oversubscribe the device. Or you can set the limit as an absolute value by entering an integer between 1 and 5 and selecting

Absolute


MAC Entries—(Transparent mode only) Sets the limit for MAC address entries in the MAC address table. Select the check box to enable this limit. You can set the limit as a percentage by entering any integer greater than 1 and selecting

Percent

from the list. You can assign more than 100 percent if you want to oversubscribe the device. Or you can set the limit as an absolute value by entering an integer between 0 (system limit) and 65535 and selecting

Absolute

from the list.

In the Rate Limited Resources area, set the rate limit for resources.

If you do not set a limit, the limit is inherited from the default class. If the default class does not set a limit, then it is unlimited by default.

You can set one or more of the following limits:

•

Conns/sec—Sets the limit for connections per second. Select the check box to enable this limit. If you set the limit to 0, it is unlimited.

•

•

Syslogs/sec—Sets the limit for system log messages per second. Select the check box to enable this limit. If you set the limit to 0, it is unlimited.

Inspects/sec—Sets the limit for application inspections per second. Select the check box to enable this limit. If you set the limit to 0, it is unlimited.

Click

OK

.

Configuring a Security Context

The security context definition in the system configuration identifies the context name, configuration file

URL, and interfaces that a context can use.

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6-17



Prerequisites

•

•


Configure physical interface parameters, VLAN subinterfaces, and redundant interfaces according to the

“Starting Interface Configuration (ASA 5510 and Higher)” section on page 8-9 .

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11


System


On the Context Management > Security Contexts pane, click

Add

.

The Add Context dialog box appears.

In the Security Context field, enter the context name as a string up to 32 characters long.

This name is case sensitive, so you can have two contexts named “customerA” and “CustomerA,” for example. “System” or “Null” (in upper or lower case letters) are reserved names, and cannot be used.

In the Interface Allocation area, click the

Add

button to assign an interface to the context.

From the Interfaces > Physical Interface drop-down list, choose an interface.

You can assign the main interface, in which case you leave the subinterface ID blank, or you can assign a subinterface or a range of subinterfaces associated with this interface. In transparent firewall mode, only interfaces that have not been allocated to other contexts are shown. If the main interface was already assigned to another context, then you must choose a subinterface.

(Optional) In the Interfaces > Subinterface Range (optional) drop-down list, choose a subinterface ID.

For a range of subinterface IDs, choose the ending ID in the second drop-down list, if available.

In transparent firewall mode, only subinterfaces that have not been allocated to other contexts are shown.

(Optional) In the Aliased Names area, check

Use Aliased Name in Context

to set an aliased name for this interface to be used in the context configuration instead of the interface ID.

a.

In the Name field, sets the aliased name.

An aliased name must start with a letter, end with a letter, and have as interior characters only letters, digits, or an underscore. This field lets you specify a name that ends with a letter or underscore; to add an optional digit after the name, set the digit in the Range field.

b.

(Optional) In the Range field, set the numeric suffix for the aliased name.

If you have a range of subinterfaces, you can enter a range of digits to be appended to the name.

(Optional) To enable context users to see physical interface properties even if you set an aliased name, check

Show Hardware Properties in Context

.

Click

OK

to return to the Add Context dialog box.

(Optional) If you use IPS virtual sensors, then assign a sensor to the context in the IPS Sensor Allocation area.

For detailed information about IPS and virtual sensors, see

Chapter 54, “Configuring the IPS

Application on the AIP SSM and SSC.”

(Optional) To assign this context to a resource class, choose a class name from the Resource Assignment

> Resource Class drop-down list.

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Step 12

Step 13

Step 14

You can add or edit a resource class directly from this area. See the

“Configuring a Class for Resource

Management” section on page 6-15 for more information.

To set the context configuration location, identify the URL by choosing a file system type from the

Config URL drop-down list and entering a path in the field.

For example, the combined URL for FTP has the following format: ftp://server.example.com/configs/admin.cfg

(Optional) For external filesystems, set the username and password by clicking

Login

.

(Optional) To set the failover group for active/active failover, choose the group name in the Failover

Group drop-down list.

(Optional) Add a description in the Description field.

Automatically Assigning MAC Addresses to Context Interfaces

This section describes how to configure auto-generation of MAC addresses. The MAC address is used

to classify packets within a context. See the “Information About MAC Addresses” section on page 6-11

for more information. See also the

“Viewing Assigned MAC Addresses” section on page 6-21 .

Guidelines

•

•

•

When you configure a name for the interface in a context, the new MAC address is generated immediately. If you enable this feature after you configure context interfaces, then MAC addresses are generated for all interfaces immediately after you enable it. If you disable this feature, the MAC address for each interface reverts to the default MAC address. For example, subinterfaces of

GigabitEthernet 0/1 revert to using the MAC address of GigabitEthernet 0/1.

For the MAC address generation method when not using a prefix (not recommended), see the


command in the


.

In the rare circumstance that the generated MAC address conflicts with another private MAC address in your network, you can manually set the MAC address for the interface within the context.

See the

“Configuring Advanced Interface Parameters” section on page 8-26 to manually set the

MAC address.

Detailed Steps

Step 1

Step 2

Step 3


System


Choose the

Configuration > Context Management > Security Contexts

pane, and check

Mac-Address auto

.

Check the

Prefix

check box, and in the field, enter a a decimal value between 0 and 65535.

OL-20339-01


6-19


Monitoring Security Contexts

This prefix is converted to a 4-digit hexadecimal number, and used as part of the MAC address. The prefix ensures that each adaptive security appliance uses unique MAC addresses, so you can have

multiple adaptive security appliances on a network segment, for example. See the “MAC Address

Format”

section for more information about how the prefix is used.


This section describes how to view and monitor context information and includes the following topics:

•

Monitoring Context Resource Usage, page 6-20

•

Viewing Assigned MAC Addresses, page 6-21

Monitoring Context Resource Usage

To monitor resource usage of all contexts from the system execution space, perform the following steps:

6-20

Step 1

Step 2

Step 3

If you are not already in the System mode, in the Device List pane, double-click

System


Click the

Monitoring

button on the toolbar.

Click

Context Resource Usage

.

Click each resource type to view the resource usage for all contexts:

•

ASDM

—Shows the usage of ASDM connections.

–

–

Context—Shows the name of each context.

Existing Connections (#)—Shows the number of existing connections.

•

•

–

–

Existing Connections (%)—Shows the connections used by this context as a percentage of the total number of connections used by all contexts.

Peak Connections (#)—Shows the peak number of connections since the statistics were last cleared, either using the

clear resource usage

command or because the device rebooted.

Telnet

—Shows the usage of Telnet connections.

–


–

–



–




SSH

—Shows the usage of SSH connections.

–



OL-20339-01


Step 4


–


•

•

•

–

–





Xlates

—Shows the usage of netword address translations.

–


–

–

Xlates (#)—Shows the number of current xlates.

Xlates (%)—Shows the xlates used by this context as a percentage of the total number of xlates used by all contexts.

–

Peak (#)—Shows the peak number of xlates since the statistics were last cleared, either using the



NATs—

Shows the number of NAT rules.

–

–


NATs (#)—Shows the current number of NAT rules.

–

–

NATs (%)—Shows the NAT rules used by this context as a percentage of the total number of

NAT rules used by all contexts.

Peak NATs (#)—Shows the peak number of NAT rules since the statistics were last cleared, either using the



Syslogs

—Shows the rate of system log messages.

–


–

–

Syslog Rate (#/sec)—Shows the current rate of system log messages.

Syslog Rate (%)—Shows the system log messages generated by this context as a percentage of the total number of system log messages generated by all contexts.

–

Peak Syslog Rate (#/sec)—Shows the peak rate of system log messages since the statistics were last cleared, either using the



Click

Refresh

to refresh the view.

Viewing Assigned MAC Addresses

You can view auto-generated MAC addresses within the system configuration or within the context. This section includes the following topics:

•

•

Viewing MAC Addresses in the System Configuration, page 6-21

Viewing MAC Addresses Within a Context, page 6-22

Viewing MAC Addresses in the System Configuration

This section describes how to view MAC addresses in the system configuration.

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6-21



Guidelines

If you manually assign a MAC address to an interface, but also have auto-generation enabled, the auto-generated address continues to show in the configuration even though the manual MAC address is the one that is in use. If you later remove the manual MAC address, the auto-generated one shown will be used.

Detailed Steps

Step 1

Step 2


System


Choose the

Configuration > Context Management > Security Contexts

pane, and view the Primary

MAC and Secondary MAC columns.

Viewing MAC Addresses Within a Context

This section describes how to view MAC addresses within a context.

Detailed Steps

Step 1

Step 2


System


Choose the

Configuration > Interfaces

pane, and view the MAC Address address column.

This table shows the MAC address in use; if you manually assign a MAC address and also have auto-generation enabled, then you can only view the unused auto-generated address from within the system configuration.

6-22


OL-20339-01


Feature History for Multiple Context Mode


Table 6-2

lists each feature change and the platform release in which it was implemented. ASDM is backwards-compatible with multiple platform releases, so the specific ASDM release in which support was added is not listed.

Table 6-2 Feature History for Multiple Context Mode

Feature Name

Multiple security conexts

Automatic MAC address assignment

Resource management

Virtual sensors for IPS

Automatic MAC address assignement enhancements

Platform

Releases

7.0(1)

7.2(1)


Multiple context mode was introduced.

The following screens were introduced: Configuration >

Context Management.

Automatic assignment of MAC address to context interfaces was introduced.

The following screen was modified: Configuration >

Context Management > Security Contexts.

Resource management was introduced.

7.2(1)

8.0(2)

The following screen was introduced: Configuration >

Context Management > Resource Management.

The AIP SSM running IPS software Version 6.0 and above can run multiple virtual sensors, which means you can configure multiple security policies on the AIP SSM. You can assign each context or single mode adaptive security appliance to one or more virtual sensors, or you can assign multiple security contexts to the same virtual sensor.



8.0(5)/8.2(2) The MAC address format was changed to use a prefix, to use a fixed starting value (A2), and to use a different scheme for the primary and secondary unit MAC addresses in a failover pair. The MAC addresess are also now persistent accross reloads. The command parser now checks if auto-generation is enabled; if you want to also manually assign a MAC address, you cannot start the manual MAC address with A2.



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6-23



6-24


OL-20339-01

Using the Startup Wizard

C H A P T E R

7

The ASDM Startup Wizard guides you through the initial configuration of the adaptive security appliance, and helps you define its settings.


•

•

•

•

•

Information About the Startup Wizard, page 7-1

Licensing Requirements for the Startup Wizard, page 7-1

Prerequisites for the Startup Wizard, page 7-2


•

•

•

•

Startup Wizard Screens for ASA 5500 Series Adaptive Security Appliances, page 7-3

Startup Wizard Screens for the ASA 5505 Adaptive Security Appliance, page 7-3

Configuring IPv6 Neighbor Discovery, page 7-18

Configuring IPv6 Static Neighbors, page 7-25

Feature History for the Startup Wizard, page 7-29

Information About the Startup Wizard

To access this feature in the main ASDM application window, choose one of the following:

•

Wizards > Startup Wizard

.

• Configuration > Device Setup > Startup Wizard,

and then click

Launch Startup Wizard

.

Licensing Requirements for the Startup Wizard

The following table shows the licensing requirements for this feature:

Model

All models


Base License

Cisco ASA 5500 Series Configuration Guide using ASDM

7-1 OL-20339-01

Chapter 7 Using the Startup Wizard

Prerequisites for the Startup Wizard

Prerequisites for the Startup Wizard

To complete the Startup Wizard, make sure that you have the following information available:

•

The hostname

•

•

•

•

•

•

The domain name

A password to restrict administrative access through ASDM or the CLI

The IP address information of the outside interface

Other interfaces, such as the inside or DMZ interfaces

NAT or PAT rules

DHCP settings for the inside interface, for use with a DHCP server




Supported in single and multiple context modes, as noted in

Table 7-1

.


Supported in routed and transparent firewall modes, as noted in

Table 7-1

.


Supports sessions in Stateful Failover.

IPv6 Guidelines

Supports IPv6.


Supports all models.


Supports the AIP SSM/SSC for IPS.

7-2


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Startup Wizard Screens for ASA 5500 Series Adaptive Security Appliances

Startup Wizard Screens for ASA 5500 Series Adaptive Security

Appliances

Table 7-1

lists all of the required Startup Wizard screens for configuring the ASA 5500 series adaptive security appliances and IPS, if you have an AIP SSM installed. The actual sequence of screens is determined by your specified configuration selections. The Availability columns lists the mode or modes in which each screen appears and provides additional configuration information. Click the name to view information for the selected screen.

Table 7-1 Startup Wizard Screens for ASA 5500 Series Adaptive Security Appliances

Screen Name

Step 1 - Starting Point or Welcome, page 7-4

Step 2 - Basic Configuration, page 7-5

Step 3 - Time Zone and Clock Configuration, page 7-5

Step 4 - Auto Update Server, page 7-6

Availability

All modes.

Not available in multiple mode.

Step 5 - Management IP Address Configuration, page 7-6

Outside Interface Configuration, page 7-28

Outside Interface Configuration - PPPoE, page 7-27

Interface Configuration, page 7-27

Other Interfaces Configuration, page 7-16

Step 13 - Static Routes, page 7-11

Step 14 - DHCP Server, page 7-11

Step 15 - Address Translation (NAT/PAT), page 7-12

Step 16 - Administrative Access, page 7-13

Step 18 - Startup Wizard Summary, page 7-16

Single, routed, and transparent modes. If enabled

in single transparent mode, the Interface

Configuration

and Step 14 - DHCP Server

screens are not available.

Single, transparent mode only.

Single, routed mode only.


All modes.


All modes.

Startup Wizard Screens for the ASA 5505 Adaptive Security

Appliance

Table 7-2

lists all of the required Startup Wizard screens for configuring only the ASA 5505 adaptive security appliance and IPS, if you have an AIP SSC installed. The sequence of screens listed represents configuration for the single, routed mode. The Availability columns lists the mode or modes in which each screen appears and provides additional configuration information. Click the name to view information for the selected screen.

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7-3


Startup Wizard Screens for the ASA 5505 Adaptive Security Appliance

Table 7-2 Startup Wizard Screens for the ASA 5505 Adaptive Security Appliance

Screen Name and Sequence

Step 1 - Starting Point or Welcome, page 7-4

Step 2 - Basic Configuration, page 7-5

Availability

All modes. The Teleworker option in

Step 2

- Basic Configuration is available only on

the ASA 5505.

Step 3 - Time Zone and Clock Configuration, page 7-5

All modes.

Step 4 - Auto Update Server, page 7-6

Single, routed, and transparent modes.

Enabled only if configured for teleworker usage.


Step 5 - Management IP Address Configuration, page 7-6

Step 6 - Interface Selection, page 7-6


Step 7 - Switch Port Allocation, page 7-7

Step 8 - Interface IP Address Configuration, page 7-8

Step 9 - Internet Interface Configuration - PPPoE, page 7-8

Step 10 - Business Interface Configuration - PPPoE, page 7-9

Step 11 - Home Interface Configuration - PPPoE, page 7-10

Step 12 - General Interface Configuration, page 7-10

Step 13 - Static Routes, page 7-11

All modes. Enabled only if configured for teleworker usage.

All modes.

Step 14 - DHCP Server, page 7-11

Step 15 - Address Translation (NAT/PAT), page 7-12


Step 16 - Administrative Access, page 7-13

All modes.

Step 17 - Easy VPN Remote Configuration, page 7-14

Single, routed mode, only when enabled for teleworker usage.

Step 18 - Startup Wizard Summary, page 7-16

All modes.

Step 1 - Starting Point or Welcome

Step 1

Step 2

Step 3

Step 4

Step 5

To change the existing configuration, click the

Modify existing configuration

radio button.

To set the configuration at the factory default values for the inside interface, click the

Reset configuration to factory defaults

radio button.

To configure the IP address and subnet mask of the management interface, check the

Configure the IP address of the management interface

check box.

Specify the IP address of the management interface.

Choose the subnet mask of the management interface from the drop-down list.

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OL-20339-01



Step 6

Note

If you reset the configuration to factory defaults, you cannot undo these changes by clicking

Cancel

or by closing this screen.

Click

Next

to continue.

Step 2 - Basic Configuration

Step 1

Step 2

Step 3

Step 4

To specify a group of configuration settings for a remote worker, check the

Configure the device for

Teleworker usage

check box. For more information, see

Step 17 - Easy VPN Remote Configuration, page 7-14

.

Specify a hostname for the adaptive security appliance. The hostname can be up to 63 alphanumeric characters in mixed case.

Specify the IPSec domain name of the adaptive security appliance, which can be used for certificates.

The domain name can be a maximum of 63 alphanumeric characters, with no special characters or spaces.

The privileged mode (enable) password is required to administer the adaptive security appliance through

ASDM or the CLI. To change the current privileged mode (enable) password, check the

Change privileged mode (enable) password

check box.

Note

If you leave the password field blank, a Password Confirmation dialog box appears to notify you that to do so is a high security risk.

Step 5

Step 6

Step 7

Step 8

Specify the old enable password, if one exists.

Specify the new enable password. The password is case-sensitive and can be up to 32 alphanumeric characters.

Reenter the new enable password.

Click

Next

to continue.

Step 3 - Time Zone and Clock Configuration

Step 1

Step 2

Step 3

Step 4

Step 5

Choose the time zone from the drop-down list. UTC is the default setting.

Enter the IP address of the NTP Server.

Choose the local date from the drop-down list.

Enter the time in hh:mm:ss format, using a 24-hour clock.

Click

Next

to continue.

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7-5



Step 4 - Auto Update Server

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Step 12

To enable communication between the adaptive security appliance and an Auto Update Server, check the

Enable Auto Update for ASA

check box.

To define the beginning of the URL for the Auto Update Server, from the Server URL drop-down list, choose either HTTPS or HTTP.

To confirm that an SSL certificate is enabled on the Auto Update Server, check the

Verify Server SSL certificate

check box.

Enter the username to log in to the Auto Update Server.

Enter the password to log in to the Auto Update Server.

Reenter the password to confirm it.

To uniquely identify the security appliance, choose the Device ID Type from the drop-down list. To enable the Device ID field and specify a particular name, choose User-defined name.

Enter a unique string to use as the security appliance ID.

(For IPS only) To enable signature and engine updates from Cisco.com, check the

Enable Signature and Engine Updates from Cisco.com

check box.

(For IPS only) Enter your Cisco.com username and password, and then confirm the password.

(For IPS only) Enter the start time in hh:mm:ss format, using a 24-hour clock.

Click

Next

to continue.

Step 5 - Management IP Address Configuration

Step 1

Step 2

Step 3

Specify the IP address of the host that can access this context for management purposes using ASDM or a session protocol.

Specify the subnet mask for the management IP address.

Click

Next

to continue.

Step 6 - Interface Selection

This screen allows you to group the eight, Fast Ethernet switch ports on the ASA 5505 into three VLANs.

These VLANs function as separate, Layer 3 networks. You can then choose or create the VLANs that define your network—one for each interface: outside (Internet), inside (Business), or DMZ (Home). A

DMZ is a separate network located in the neutral zone between a private (inside) network and a public

(outside) network.

To create three VLANs to define your network, perform the following steps:

Step 1

In the Outside VLAN or Internet VLAN area, do the following:

a.

From the Choose a VLAN drop-down list, choose a predefined outside VLAN by number.

7-6


OL-20339-01



Step 2

Step 3

Step 4 b.

a.

b.

To create a new outside VLAN, check the

Create a VLAN

check box.

c.

To enable the outside VLAN, check the

Enable VLAN

check box.

In the Inside VLAN or Business VLAN area, do the following:

From the Choose a VLAN drop-down list, choose a predefined inside VLAN by number.

To create a new inside VLAN, check the

Create a VLAN

check box.

c.

To enable the inside VLAN, check the

Enable VLAN

check box.

In the DMZ VLAN or Home VLAN (Optional) area, do the following:

a.

b.

From the Choose a VLAN drop-down list, choose a predefined inside VLAN by number.

To create a new inside VLAN, check the

Create a VLAN

check box.

•

To disable configuration of this VLAN, check the

Do not configure

check box.

Click

Next

to continue.

Step 7 - Switch Port Allocation

This screen lets you allocate switch ports to outside (Internet), inside (Business), or DMZ (Home) interfaces. The DMZ interface is not available in transparent mode. You must add the ports to the associated VLANs. By default, all switch ports begin with VLAN1.

Step 1

Step 2

Step 3

Step 4

In the Switch Ports for Outside VLAN (vlan

id

) or Switch Ports for Internet VLAN (vlan

id

) area, do the following:

a.

Choose a port to add or remove from the available list of ports.

b.

c.

Choose a port to add or remove from the allocated list of ports.

To add a port to the available or allocated list of ports, click

Add

.

d.

To remove a port from the available or allocated list of ports, click

Remove

.

In the Switch Ports for Inside VLAN (vlan

id

) or Switch Ports for Business VLAN (vlan

id)

area, do the following:

a.

b.

c.

d.




Add

.


Remove

.

In the Switch Ports for DMZ VLAN (vlan

id

) or Switch Ports for Home VLAN (vlan

id)

area, do the following:

a.


b.

c.



Add

.

d.


Remove

.

Click

Next

to continue.

OL-20339-01


7-7



Step 8 - Interface IP Address Configuration

To configure the interface through a PPPoE server, a DHCP server, or by specifying a particular IP address and subnet mask, perform the following steps:

Step 1

Step 2

Step 3

In the Outside IP Address or Internet IP Address area, do one of the following:

•

To specify an outside IP address, click the

Use the following IP address

radio button.

•

•

•

Enter the specific outside IP address and choose the subnet mask from the drop-down list.

To obtain an outside IP address from a DHCP server, click the

Use DHCP

radio button.

•

To obtain the default route for an outside IP address from a DHCP server, check the

Obtain default rote using DHCP

check box.

To obtain an outside IP address from a PPPoE server, click the

Use PPPoE

radio button.

In the Inside IP Address or Business IP Address area, do one of the following:

•

To specify an inside IP address, click the


radio button.

•

•

•

Enter the specific inside IP address and choose the subnet mask from the drop-down list.

To obtain an inside IP address from a DHCP server, click the

Use DHCP

radio button.

•

To obtain the default route for an inside IP address from a DHCP server, check the

Obtain default rote using DHCP

check box.

To obtain an inside IP address from a PPPoE server, click the

Use PPPoE

radio button.

In the DMZ IP Address or Home IP Address area, choose one of the following:

•

To specify a DMZ IP address, click the


radio button, then enter the specific DMZ IP address and choose the subnet mask from the drop-down list.

•

•

To obtain a DMZ IP address from a DHCP server, click the

Use DHCP

radio button.

To obtain a DMZ IP address from a PPPoE server, click the

Click

Next

to continue.

Use PPPoE

radio button.

Step 9 - Internet Interface Configuration - PPPoE

7-8

Note

For all ASA 5500 series models except ASA 5505, with a full license, the adaptive security appliance supports up to five interfaces, with a maximum of three outside interfaces. In restricted mode, the adaptive security appliance supports up to three interfaces, and in transparent mode, the adaptive security appliance supports up to two interfaces. After you have created the maximum number of interfaces, or the maximum number of interfaces has already been named, you may not be able to create a new VLAN, and must select an existing one.

Step 1

Step 2

Specify the name of the group on the PPPoE server. You must specify a group name to proceed.

In the User Authentication area, do the following:

a.

b.

Specify your username on the PPPoE server.

Specify your password on the PPPoE server.


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Step 3

Step 4

Step 5 c.

•

•

Confirm the PPPoE password that you entered.

In the Authentication Method area, do one of the following:

•

To use PAP authentication, click the

PAP

radio button.

To use CHAP authentication, click the

CHAP

radio button.

To use MS-CHAP authentication, click the

MS-CHAP

radio button.

In the IP Address area, do one of the following:

•

To obtain an IP address for the interface from the PPPoE server, click the

Obtain an IP address using PPPoE

radio button. This field is not visible in transparent mode.

•

Specify an IP address for the Internet interface. This field is not visible in transparent mode.

–

Specifies the IP address that you want to use for the Internet interface.

•

–

Choose a subnet mask for the Internet interface from the drop-down list.

To set the default routing using the PPPoE server, check the

Obtain default route using PPPoE

check box.

Click

Next

to continue.

Step 10 - Business Interface Configuration - PPPoE

Note


Step 1

Step 2

Step 3

Step 4

Enter the name of the group on the PPPoE server. You must specify a group name to proceed.


a.

Enter your username on the PPPoE server.

b.

•

•

Enter your password on the PPPoE server.

c.

Enter the PPPoE password that you entered.

In the Authentication Method area, choose one of the following:

To use PAP authentication, click

PAP

.

To use CHAP authentication., click

CHAP

.

•

To use MS-CHAP authentication, click

MS-CHAP

.

In the IP Address area, choose one of the following:

•

•

Click the


radio button to obtain an IP address for the interface from the PPPoE server. This option is not visible in transparent mode.

Enter an IP address for the inside interface. This option is not visible in transparent mode.

–

Enter the IP address that you want to use for the inside interface.


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Step 5

–

Choose a subnet mask for the Internet interface from the drop-down list.

•



check box.

Click

Next

to continue.

Step 11 - Home Interface Configuration - PPPoE

Note


Step 1

Step 2

Step 3

Step 4

Step 5

Enter the name of the group on the PPPoE server. You must specify a group name to proceed.


a.

Enter your username on the PPPoE server.

b.

c.

Enter your password on the PPPoE server.

Enter the PPPoE password that you entered.

In the Authentication Method area, choose one of the following:

•

•

•

To use PAP authentication, click

PAP

.

To use CHAP authentication., click

CHAP

.

To use MS-CHAP authentication, click

MS-CHAP

.


•

•

Click the


radio button to obtain an IP address for the DMZ interface from the PPPoE server. This option is not visible in transparent mode.

Enter an IP address for the DMZ interface. This option is not visible in transparent mode.

–

Enter the IP address that you want to use for the DMZ interface.

•

–

Choose a subnet mask for the DMZ interface from the drop-down list.



check box.

Click

Next

to continue.

Step 12 - General Interface Configuration

Restricted traffic is not an optional configuration. If you only have a restricted license, you must restrict traffic from one interface to any of the other interfaces. The Restrict Traffic area fields are hidden if you have a full license or if the device is in transparent mode.


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To enable and restrict traffic between interfaces and between hosts connected to the same interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4

To enable traffic between two or more interfaces with the same security level, check the

Enable traffic between two or more interfaces with the same security level

check box.

To enable traffic between two or more hosts connected to the same interface, check the

Enable traffic between two or more hosts connected to the same interface

check box.

In the Restrict traffic area, do the following:

•

•

To restrict traffic from an interface, choose an interface from the drop-down list.

To restrict traffic to an interface, choose an interface from the drop-down list.

Click

Next

to continue.

Step 13 - Static Routes

Step 1

Step 2

Step 3

Step 4

To create, edit, and remove static routes that will access networks connected to a router on any interface, perform the following steps:

Choose to filter by IPv4 addresses, IPv6 addresses, or both.

To continue, see the

“Configuring Static and Default Routes” section on page 19-2

.

Click

Next

to continue.

Adding or Editing Static Routes

The Add/Edit Static Routes dialog box lets you add, edit, or remove a static route. For more information,

see the “Configuring Static and Default Routes” section on page 19-2

.

Step 14 - DHCP Server

Step 1

Step 2

To allow connection to the DHCP server from the inside interface, check the

Enable DHCP server on the inside interface

check box.

In the DHCP Address Pool area, do the following:

•

•

Enter the starting range of the DHCP server pool in a block of IP addresses from the lowest to highest.

Enter the ending range of the DHCP server pool in a block of IP addresses from the lowest to highest.

Note

The adaptive security appliance supports up to 256 IP addresses.

Step 3

In the DHCP Parameters area, do the following:

a.

To allow automatic configuration of the DNS server, WINS server, lease length, and ping timeout settings, check the

Enable auto-configuration

check box.


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Step 4 b.

c.

Enter the IP address of the DNS server.

Enter the IP address of the WINS server.

Enter the IP address of the alternate DNS server.

d.

e.

f.

g.

Enter the IP address of the alternate WINS server.

Enter the amount of time (in seconds) that the client can use its allocated IP address before the lease expires. The default value is 3600 seconds (1 hour).

Enter the parameters for the ping timeout value in milliseconds.

Enter the domain name of the DNS server to use DNS.

h.

i.

To enable DHCP auto-configuration and choose the interface from the drop-down list, check the

Enable auto-configuration from interface

check box. The values you specify in the previous areas of this screen take precedence over the auto-configured values.

Click

Next

to continue.


Chapter 10, “Configuring DHCP.”

Step 15 - Address Translation (NAT/PAT)

PAT lets you set up a single IP address for use as the global address. In addition, you can set multiple outbound sessions to appear as if they originate from a single IP address. PAT lets up to 65,535 hosts start connections through a single outside IP address.

If you decide to use NAT, enter an address range to use for translating all addresses on the inside interface to addresses on the outside interface. The global addresses in the pool provide an IP address for each outbound connection, and for those inbound connections resulting from outbound connections.

When you use PAT, be aware of the following:

•

•

•

•

•

PAT does not work with caching name servers.

You may need to enable the corresponding inspection engine to pass multimedia application protocols through the adaptive security appliance.

PAT does not work with the

established

command.

With passive FTP, use the

inspect protocol ftp strict

command with the

access-list

command to allow outbound FTP traffic.

A DNS server on a higher level security interface cannot use PAT.

Step 1

Step 2

To enable NAT and share several external IP addresses on the inside VLAN to be used for translation, click the

Use Network Address Translation (NAT)

radio button, then do the following:

a.

Enter the first IP address in a range of IP addresses to be used for translation.

b.

c.

Enter the last IP address in a range of IP addresses to be used for translation.

(Optional) Enter the subnet mask for the range of IP addresses to be used for translation.

To enable PAT, click the

Use Port Address Translation (PAT)

radio button. If you select this option, choose one of the following:

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Step 3

Note

IPSec with PAT may not work correctly, because the outside tunnel endpoint device cannot handle multiple tunnels from one IP address.

•

•

To use the IP address of the outside interface for PAT, click the

Use the IP address on the outside interface

radio button.

To indicate a particular address to use for PAT, click the

Specify an IP address

radio button.

–

–

Enter an IP address for the outside interface for PAT.

(Optional) Choose a subnet mask from the drop-down list.

•

To allow traffic through the adaptive security appliance without translation, check the

Enable traffic through the firewall without translation

check box.

Click

Next

to continue.

Step 16 - Administrative Access

To configure management access on the adaptive security appliance, perform the following steps:

Step 1

Step 2

Step 3

Step 4

To add or change the access type, an interface, and then specify the IP address and netmask of the host network that may connect to that interface for management purposes only, see the

“Adding or Editing

Administrative Access Entry” section on page 7-13

.

•

The Type column specifies whether the host or network is accessing the adaptive security appliance through HTTP over SSL in ASDM, SSH, or Telnet.

•

•

The Interface column displays the host or network name.

The IP Address column displays the IP address of the host or network.

•

The Mask column displays the subnet mask of the host or network.

To enable a secure connection to an HTTP server to access ASDM, check the

Enable HTTP server for

HTTPS/ASDM access

check box.

To allow ASDM to collect and display statistics, check the

Enable ASDM history metrics

check box.

Click

Next

to continue.

Adding or Editing Administrative Access Entry

Step 1

Step 2

To configure the hosts, in the main ASDM application window, choose one of the following:

•

•

Configuration > Properties > Device Access > HTTPS/ASDM

Configuration > Properties > Device Access > Telnet

•

•

Configuration > Properties > Device Access > SSH

Configuration > Properties > History Metrics

Choose one of the following preconfigured connections for the CLI console sessions from the Access

Type drop-down list:


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•

•

•

ASDM/HTTPS

SSH

Telnet

Note

ASDM uses HTTP over SSL (HTTPS) for all communication with the adaptive security appliance.

Step 3

Step 4

Step 5

Step 6

Choose the interface name from the Interface drop-down list.

Enter an IP address for the interface.

Enter a subnet mask for the interface from the Subnet Mask drop-down list.

Click

OK

to save these settings and return to the Administrative Access screen.

Step 17 - Easy VPN Remote Configuration

The adaptive security appliance can act as an Easy VPN remote device to enable deployment of VPNs to remote locations. The following two modes of operation are available:

•

•

Client Mode

Network Extension Mode

In Client Mode, the adaptive security appliance does not expose the IP addresses of clients on the inside network. Instead, the adaptive security appliance uses NAT to translate the IP addresses on the private network to a single, assigned IP address. In this mode, you cannot ping or access any device from outside the private network.

In Network Extension Mode, the adaptive security appliance does not protect the IP addresses of local hosts by substituting an assigned IP address. Therefore, hosts on the other side of the VPN connection can communicate directly with hosts on the local network.

To configure the adaptive security appliance in one of these two modes, use the following guidelines:

•

Use Client Mode if:

–

–

You want VPN connections to be initiated by client traffic.

You want the IP addresses of local hosts to be hidden from remote networks.

•

–

You are using DHCP on the ASA 5505 to provide IP addresses to local hosts.

Use Network Extension Mode if:

–

–

You want VPN connections to remain open even when not required for transmitting traffic.

You want remote hosts to be able to communicate directly with hosts on the local network.

–

Hosts on the local network have static IP addresses.

Note

To access this screen, you must have checked the

Configure the device for Teleworker usage

check box in

Step 2 - Basic Configuration and unchecked the

Enable Auto Update

check box in the

Interface

Configuration

.

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To form a secure VPN tunnel between the adaptive security appliance and a remote Cisco VPN 3000 concentrator, Cisco router, or adaptive security appliance that is acting as an Easy VPN server, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

To enable the security appliance to act as an Easy VPN remote device, check the

Enable Easy VPN remote

check box. If you do not enable this feature, any host that has access to the security appliance outside interface through a VPN tunnel can manage it remotely.

In the Mode area, choose one of the following:

•

If you are using a DHCP server to generate dynamic IP addresses for hosts on your inside network, click the

Client mode

radio button.

•

If hosts on your inside network have static IP addresses, click the

Network Extension mode

radio button.

In the Group Settings area, do the following:

a.

b.

To use X.509 certificates to enable the IPSec main mode, click the

Use X.509 Certificate

radio button. Choose the trustpoint from the drop-down list.

To enter a password for a group of users, click the

Use group password

radio button.

a.

b.

–

–

Enter a name for the user group.

Enter a password for the user group.

–

Confirm the password.

In the User Settings area, do the following:

Enter a username for your settings.

Enter a password for your settings.

c.

Confirm the password for your settings.

In the Easy VPN Server area, do the following:

a.

b.

Enter the IP address of the primary Easy VPN server.

Enter the IP address of a secondary Easy VPN server.

Note

The adaptive security appliance supports a maximum of 11 Easy VPN servers: one primary and up to ten secondary. Before you can connect the ASA Easy VPN remote device to the Easy VPN server, you must establish network connectivity between both devices through your ISP. After you have connected the ASA 5500 series adaptive security appliance to the DSL or cable modem, follow the instructions provided by your ISP to complete the network connection. You can obtain an IP address through a PPPoE server, a DHCP server, or a static configuration.

Step 6

Click

Next

to continue.

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7-15



Step 18 - Startup Wizard Summary

This screen summarizes all of the configuration settings that you have made for the adaptive security appliance.

Step 1

Step 2

To change any of the settings in previous screens, click

Back

.

Choose one of the following:

•

•

If you ran the Startup Wizard directly from a browser, when you click

Finish

, the configuration settings that you created through the wizard are sent to the adaptive security appliance and saved in flash memory automatically.

If you ran the Startup Wizard from within ASDM, you must explicitly save the configuration in flash memory by choosing

File > Save Running Configuration to Flash

.

Other Interfaces Configuration

To configure the remaining interfaces, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Select the interface to change and click

Edit

.

The Edit Interface dialog box appears.

•

•

The Interface field displays the network interface on which the original host or network resides.

The Name field displays the name of the interface being configured.

•

The Security Level field displays the security level range for the interface from 0 to 100, with 100 assigned to the inside interface and 0 assigned to the outside interface. Perimeter interfaces can use any number between 1 and 99. Security levels between 0 and 100 for perimeter interfaces are not set by default.

To assign the same security level to two or more interfaces, and enable traffic between them, check the

Enable traffic between two or more interfaces with same security levels

check box.

If you have an interface between two or more hosts and want to enable traffic between them, check the


check box.

Click

Next

to continue.

Editing Interfaces

On the Interface Properties and IPv4 Settings tab, perform the following steps:

Step 1

Step 2

The Interface field is display-only and shows the name of the selected interface to edit. The Enable interface check box is checked by default.

The Interface Name field displays the name of the selected interface. Change the name of the interface, if needed.

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Step 3

Step 4

The Security Level field displays the security level of the selected interface. Change the security level for the interface, if needed. If you change the security level of the interface to a lower level, a warning message appears.

In the IP Address area, choose one of the following three options:

•

To enter a specific IP address for an interface, click the


radio button.

–

–

Enter the IP address of the interface.

Choose an existing subnet mask from the drop-down list.

•

•

To use the security appliance as a DHCP server, click the

Use DHCP

radio button.

To use PPPoE to provide an authenticated method of assigning an IP address to an outside interface, click the

Use PPPoE

radio button.

Note

Because PPPoE is permitted on multiple interfaces, each instance of the PPPoE client may require different authentication levels with different usernames and passwords.

Step 5

Step 6

–

–

–

Enter a group name to proceed.

Enter the PPPoE username and password, and confirm the password.

PAP is the default authentication method for PPPoE. You have the option of configuring CHAP or MS-CHAP manually by clicking the applicable radio button.


•

To assign an IP address using PPPoE, click the

Obtain IP Address using PPPoE

radio button.

•

To assign a particular IP address, click the


radio button.

–

Enter the IP address.

–

Choose a subnet mask from the drop-down list.

Click

OK

to save these settings.

On the IPv6 Settings tab, perform the following steps:

Step 1

Step 2

Step 3

Step 4

To configure Neighbor Discovery settings, see the

“Configuring IPv6 Neighbor Discovery” section on page 7-18

.

To configure IPv6 addresses on an interface, see the

“Configuring IPv6 Addresses on an Interface” section on page 7-21 .

To configure IPv6 prefixes on an interface, see the

“Configuring IPv6 Prefixes on an Interface” section on page 7-21 .

Click

OK

to save these settings.

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The IPv6 neighbor discovery process uses ICMPv6 messages and solicited-node multicast addresses to determine the link-layer address of a neighbor on the same network (local link), verify the reachability of a neighbor, and keep track of neighboring routers. For more information about IPv6 Neighbor

Discovery, see Chapter 25, “Configuring IPv6 Neighbor Discovery.”


•

•

•

Configuring Neighbor Solicitation Messages, page 7-18

Configuring Router Advertisement Messages, page 7-22

Configuring IPv6 Static Neighbors, page 7-25

Configuring Neighbor Solicitation Messages

Neighbor solicitation messages (ICMPv6 Type 135) are sent on the local link by nodes attempting to discover the link-layer addresses of other nodes on the local link. The neighbor solicitation message is sent to the solicited-node multicast address. The source address in the neighbor solicitation message is the IPv6 address of the node sending the neighbor solicitation message. The neighbor solicitation message also includes the link-layer address of the source node.

After receiving a neighbor solicitation message, the destination node replies by sending a neighbor advertisement message (ICPMv6 Type 136) on the local link. The source address in the neighbor advertisement message is the IPv6 address of the node sending the neighbor advertisement message; the destination address is the IPv6 address of the node that sent the neighbor solicitation message. The data portion of the neighbor advertisement message includes the link-layer address of the node sending the neighbor advertisement message. After the source node receives the neighbor advertisement, the source node and destination node can communicate.

Figure 7-1

shows the neighbor solicitation and response process.

Figure 7-1 IPv6 Neighbor Discovery—Neighbor Solicitation Message

ICMPv6 Type = 135

Src = A

Dst = solicited-node multicast of B

Data = link-layer address of A

Query = what is your link address?

ICMPv6 Type = 136

Src = B

Dst = A

Data = link-layer address of B

A and B can now exchange packets on this link

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Neighbor solicitation messages are also used to verify the reachability of a neighbor after the link-layer address of a neighbor is identified. When a node wants to verify the reachability of a neighbor, the destination address in a neighbor solicitation message is the unicast address of the neighbor.

Neighbor advertisement messages are also sent when there is a change in the link-layer address of a node on a local link. When there is such a change, the destination address for the neighbor advertisement is the all-nodes multicast address.

You can configure the neighbor solicitation message interval and neighbor reachable time on a per-interface basis.

In addition, you can configure DAD settings, IPv6 addresses, and IPv6 prefixes. For more information, see the following sections:

•

Configuring the Neighbor Solicitation Message Interval, page 7-19

•

•

•

•

Configuring the Neighbor Reachable Time, page 7-19

Configuring DAD Settings, page 7-20

Configuring IPv6 Addresses on an Interface, page 7-21

Configuring IPv6 Prefixes on an Interface, page 7-21

Configuring the Neighbor Solicitation Message Interval

You can configure the interval between IPv6 neighbor solicitation retransmissions on an interface. Valid values range from 1000 to 3600000 milliseconds. The default value is 1000 milliseconds. This setting is also sent in router advertisement messages.

To configure the neighbor solicitation message interval, perform the following steps:

Step 3

Step 4

Step 5

Step 6

Step 7

Step 1

Step 2

Choose

Configuration

>

Device Setup

>

Interfaces

.

Choose the interface on which to configure the neighbor solicitation interval. The interface must have been configured with an IPv6 address. See the

“Configuring IPv6 Neighbor Discovery” section on page 7-18


Click

Edit

. The Edit Interface dialog box appears with three tabs: General, Advanced, and IPv6.

Click the

IPv6

tab.

In the NS Interval field, enter the time interval.

Click

OK

.

Click

Apply

to save the configuration.

Configuring the Neighbor Reachable Time

The neighbor reachable time enables detecting unavailable neighbors. Shorter configured times enable detecting unavailable neighbors more quickly; however, shorter times consume more IPv6 network bandwidth and processing resources in all IPv6 network devices. Very short configured times are not recommended in normal IPv6 operation.

Valid time values range from 0 to 3600000 milliseconds. The default is 0; however, when you use 0, the reachable time is sent as undetermined. It is up to the receiving devices to set and track the reachable time value.

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7-19



To configure the amount of time that a remote IPv6 node is considered reachable after a reachability confirmation event has occurred, perform the following steps:

Step 3

Step 4

Step 5

Step 6

Step 7

Step 1

Step 2

Choose

Configuration

>

Device Setup

>

Interfaces

.

Choose the interface for which you want to configure the time. The interface must have been configured with an IPv6 address. For more information, see the

“Configuring IPv6 Neighbor Discovery” section on page 7-18 .

Click

Edit


Click the

IPv6

tab.

In the Reachable Time field, enter a valid value.

Click

OK

.

Click

Apply


Configuring DAD Settings

Duplicate Address Detection (DAD) settings are part of the Neighbor Discovery configuration. DAD verifies the uniqueness of new unicast IPv6 addresses before they are assigned and ensures that duplicate

IPv6 addresses are detected in the network on a link basis.

To specify DAD settings on the interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Enter the number of allowed DAD attempts. This setting configures the number of consecutive neighbor solicitation messages that are sent on an interface while DAD is performed on IPv6 addresses. Valid values are from 0 to 600. A zero value disables DAD processing on the specified interface. The default is one message.

Enter the neighbor solicitation message interval. The neighbor solicitation message requests the link-layer address of a target node. Valid values are from 1000 to 3600000 milliseconds. The default is

1000 milliseconds.

Enter the amount of time in seconds that a remote IPv6 node is considered reachable after a reachability confirmation event has occurred. Valid values are from 1000 to 3600000 milliseconds. The default is zero. A configured time enables the detection of unavailable neighbors. Shorter times enable detection more quickly; however, very short configured times are not recommended in normal IPv6 operation.

Enter the amount of time that IPv6 router advertisement transmissions are considered valid. Valid values are from 3 to 1800 seconds. The default is 200 seconds. Router advertisement transmissions include a preference level and a lifetime field for each advertised router address. These transmissions provide route information and indicate that the router is still operational to network hosts. By default, these transmissions are sent every 400 to 600 seconds.

Enter the interval between IPv6 router advertisement transmissions. Valid values are from 3 to 1800 seconds. The default is 200 seconds. To have the router advertisement transmission interval be listed in milliseconds, check the

RA Interval in Milliseconds

check box.

To allow the generation of addresses for hosts, make sure that the Suppress RA check box is unchecked.

This is the default setting if IPv6 unicast routing is enabled. To prevent the generation of IPv6 router advertisement transmissions, check the

Suppress RA

check box.

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Step 7



Configuring IPv6 Addresses on an Interface

To configure IPv6 addresses on an interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

If you have not configured any IPv6 addresses with the CLI, to enable IPv6 addressing, check the

Enable

IPv6

check box.

To make sure that the source addresses of IPv6 packets received on that interface are verified according to the source MAC addresses to ensure that the interface identifiers use the modified EUI-64 format, check the

Enforce EUI-64

check box. If the interface identifiers do not conform to the modified EUI-64 format, an error message appears.

If you are not going to assign any other IPv6 addresses, to set the link-local address manually, enter an address in the Link-local address field. A link-local address should start with FE8, FE9, FEA, or FEB, for example fe80::20d:88ff:feee:6a82.

Alternatively, click the ellipsis to choose a link-local address from the Browse Link-local address dialog box.

After you have selected the link-local address, click

OK

to return to the IPv6 tab.

The selected link-local address appears in the Link-local address field.

To enable address autoconfiguration, check the

Enable address autoconfiguration

check box. During the stateless autoconfiguration process, duplicate address detection (DAD) verifies the uniqueness of new unicast IPv6 addresses before the addresses are assigned to interfaces (the new addresses remain in a tentative state while duplicate address detection is performed). Duplicate address detection is performed first on the new link-local address. When the link local address is verified as unique, then duplicate address detection is performed all the other IPv6 unicast addresses on the interface. For more information about DAD, see the

“Configuring DAD Settings” section on page 7-20 .

In the Interface IPv6 Addresses area, click

Add

.

The Add IPv6 Address for Interface dialog box appears.

(Optional) Check the

EUI-64

check box.

Click

OK

to save your settings.

The Interface IPv6 Addresses Address field appears with the modified EUI-64 address.

Note

You cannot use IPv6 addresses for the failover LAN and state links. For more information, see

the “Configuring Failover with the High Availability and Scalability Wizard” section on page 58-2

.

Step 9


“Configuring IPv6 Prefixes on an Interface” section on page 7-21

.

Configuring IPv6 Prefixes on an Interface

To configure IPv6 prefixes on an interface, perform the following steps:

Step 1

In the Interface IPv6 Prefixes area, click

Add

.

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7-21



Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

The Add IPv6 Prefix for Interface dialog box appears.

Enter the IPv6 address with the prefix length.

(Optional) To configure the IPv6 address manually, check the

No Auto-Configuration

check box. This setting indicates to hosts on the local link that the specified prefix cannot be used for IPv6 autoconfiguration.

(Optional) To indicate that the IPv6 prefix is not advertised, check the

No Advertisements

check box.

(Optional) The

Off Link

check box indicates that the specified prefix is assigned to the link. Nodes sending traffic to addresses that contain the specified prefix consider the destination to be locally reachable on the link. This prefix should not be used for on-link determination.

In the Prefix Lifetime area, click the

Lifetime Duration

radio button, and specify the following:

a.

A valid lifetime for the prefix in seconds from the drop-down list. This setting is the amount of time that the specified IPv6 prefix is advertised as being valid. The maximum value represents infinity.

Valid values are from 0 to 4294967295. The default is 2592000 (30 days).

b.

A preferred lifetime for the prefix from the drop-down list. This setting is the amount of time that the specified IPv6 prefix is advertised as being preferred. The maximum value represents infinity.

Valid values are from 0 to 4294967295. The default setting is 604800 (seven days).

To define a prefix lifetime expiration date, click the

Lifetime Expiration Date


a.

b.

Choose a valid month and day from the drop-down list, and then enter a time in hh:mm format.

Choose a preferred month and day from the drop-down list, and then enter a time in hh:mm format.

Click

OK


The Interface IPv6 Prefixes Address field appears with the preferred and valid dates.

Configuring Router Advertisement Messages

Router advertisement messages (ICMPv6 Type 134) are periodically sent from each IPv6 configured interface of the adaptive security appliance. The router advertisement messages are sent to the all-nodes multicast address

Figure 7-2

shows an example of a router advertisement message.

Figure 6-2 shows the flow of router advertisement messages from an IPv6 configured interface.

Figure 7-2 IPv6 Neighbor Discovery—Router Advertisement Message

Router advertisement


Router advertisement packet definitions:

ICMPv6 Type = 134

Src = router link-local address

Dst = all-nodes multicast address

Data = options, prefix, lifetime, autoconfig flag

7-22


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Router advertisement messages typically include the following information:

•

•

•

One or more IPv6 prefix that nodes on the local link can use to automatically configure their IPv6 addresses.

Lifetime information for each prefix included in the advertisement.

•

Sets of flags that indicate the type of autoconfiguration (stateless or stateful) that can be completed.

Default router information (whether the router sending the advertisement should be used as a default router and, if so, the amount of time (in seconds) the router should be used as a default router).

•

•

Additional information for hosts, such as the hop limit and MTU a host should use in packets that it originates.

The amount of time between neighbor solicitation message retransmissions on a given link.

•

The amount of time a node considers a neighbor reachable.

Router advertisements are also sent in response to router solicitation messages (ICMPv6 Type 133).

Router solicitation messages are sent by hosts at system startup so that the host can immediately autoconfigure without needing to wait for the next scheduled router advertisement message. Because router solicitation messages are usually sent by hosts at system startup, and the host does not have a configured unicast address, the source address in router solicitation messages is usually the unspecified

IPv6 address (0:0:0:0:0:0:0:0). If the host has a configured unicast address, the unicast address of the interface sending the router solicitation message is used as the source address in the message. The destination address in router solicitation messages is the all-routers multicast address with scope of the link. When a router advertisement is sent in response to a router solicitation, the destination address in the router advertisement message is the unicast address of the source of the router solicitation message.

You can configure the following settings for router advertisement messages:

•

The time interval between periodic router advertisement messages.

•

•

The router lifetime value, which indicates the amount of time IPv6 nodes should consider the adaptive security appliance to be the default router.

The IPv6 network prefixes used on the link.

•

Whether or not an interface transmits router advertisement messages.

Unless otherwise noted, the router advertisement message settings are specific to an interface and are entered in interface configuration mode. For information about changing these settings, see the following sections:

•

•

•

Configuring the Router Advertisement Transmission Interval, page 7-23

Configuring the Router Lifetime Value, page 7-24

Suppressing Router Advertisement Messages, page 7-25

Configuring the Router Advertisement Transmission Interval

By default, router advertisements are sent out every 200 seconds. Valid values range from 3 to 1800 seconds.

The interval between transmissions should be less than or equal to the IPv6 router advertisement lifetime if the adaptive security appliance is configured as a default router. For more information, see the

“Configuring the Router Lifetime Value” section on page 7-24

. To prevent synchronization with other

IPv6 nodes, randomly adjust the actual value used to within 20 percent of the desired value.

To change the interval between router advertisement transmissions on an interface, perform the following steps:

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7-23



Step 1

Step 2

Step 3

Step 4

Step 5

Choose

Configuration

>

Device Setup

>

Interfaces

.

Select the interface for which you want to configure the time.

The interface must have been configured with an IPv6 address. For more information, see the


Click

Edit


Click the

IPv6

tab.

In the RA Interval field, enter a valid transmission interval value.

Note

(Optional) To add a router advertisement transmission interval value in milliseconds instead, check the


check box, and enter a value from 500 to 1800000.

Step 6

Step 7

Click

OK

.

Click

Apply


Configuring the Router Lifetime Value

The router lifetime value specifies how long nodes on the local link should consider the adaptive security appliance as the default router on the link. Valid values range from 0 to 9000 seconds. The default is

1800 seconds. Entering 0 indicates that the adaptive security appliance should not be considered a default router on the selected interface.

To configure the router lifetime value in IPv6 router advertisements on an interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Choose

Configuration

>

Device Setup

>

Interfaces

.

Select the interface for which you want to configure the lifetime value.

The interface must have been configured with an IPv6 address. For more information see the


Click

Edit

.

The Edit Interface dialog box appears with three tabs: General, Advanced, and IPv6.

Click the

IPv6

tab.

In the RA Lifetime field, enter a valid lifetime value.

Click

OK

.

Click

Apply


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Configuring IPv6 Static Neighbors

Suppressing Router Advertisement Messages

By default, router advertisement messages are automatically sent in response to router solicitation messages. You may want to disable these messages on any interface for which you do not want the adaptive security appliance to supply the IPv6 prefix (for example, the outside interface).

To suppress IPv6 router advertisement transmissions on an interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Choose

Configuration

>

Device Setup

>

Interfaces

.

Select the interface for which you want to configure the lifetime value. The interface must have been configured with an IPv6 address. For more information, see the


Click

Edit

.


Click the

IPv6

tab.

Check the

Suppress RA

check box.

Verify that the router advertisement message is suppressed on the interface that is configured for the IPv6 address.


•

•

•


Adding an IPv6 Static Neighbor, page 7-25

Editing Static Neighbors, page 7-26

•

Deleting Static Neighbors, page 7-26

Viewing and Clearing Dynamic Neighbors, page 7-27

Adding an IPv6 Static Neighbor

Make sure that IPv6 is enabled on at least one interface before trying to add a neighbor, or ASDM returns an error message indicating that the configuration failed. For information about configuring IPv6 on an

interface, see the “Configuring a Static IPv6 Neighbor” section on page 25-18 .

For information about configuring IPv6 Neighbor Discovery, see the

“Configuring IPv6 Neighbor

Discovery” section on page 7-18

.

To add an IPv6 static neighbor, perform the following steps:

Step 1

Step 2

Step 3

Choose

Configuration

>

Device Management

>

Advanced

>

IPv6 Neighbor Discovery Cache

.

Click

Add

.

The Add IPv6 Static Neighbor dialog box appears.

From the Interface Name drop-down list, choose an interface on which to add the neighbor.

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Step 4

Step 5

Step 6

In the IP Address field, enter the IPv6 address that corresponds to the local data-link address, or click the ellipsis (...) to browse for an address.

If an entry for the specified IPv6 address already exists in the neighbor discovery cache—learned through the IPv6 neighbor discovery process—the entry is automatically converted to a static entry.

In the MAC address field, enter the local data-line (hardware) MAC address.

Click

OK

.

Note

Before you apply the changes and save the configuration, you can click

Reset

to cancel any changes and restore the original values.

Step 7

Click

Apply


Editing Static Neighbors

To edit a static neighbor that is defined in your configuration, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Choose

Configuration

>


>

Advanced

>


.

Select the neighbor from the main pane, and click

Edit

.

The Edit IPv6 Static Neighbor dialog box appears.

Enter all necessary changes, and click

OK

.

Click

Apply

to save the changes to your configuration.

Deleting Static Neighbors

To delete a static neighbor from your configuration, perform the following steps:

Step 1

Step 2

Step 3

Choose

Configuration

>


>

Advanced

>


.

Select the neighbor to delete from the main pane, and click

Delete

.

The selected neighbor is removed from the list.

Click

Apply

to save the change to your current configuration.

Note

Before you apply the changes and permanently delete the neighbor from your configuration, you can click

Reset

to restore the original values.

7-26


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Viewing and Clearing Dynamic Neighbors

When a host or node communicates with a neighbor, the neighbor is added to the neighbor discovery cache. The neighbor is removed from the cache when there is no longer any communication with the neighbor.

To view dynamically discovered neighbors and to clear neighbors from the IPv6 Neighbor Discovery

Cache, perform the following steps:

Step 1

Step 2

Choose

Monitoring

>

Interface Graphs

>


.

You can view all static and dynamically discovered neighbors from the IPv6 Neighbor Discovery Cache pane.

To clear all dynamically discovered neighbors from the cache, click

Clear Dynamic Neighbor Entries

.

The neighbor information is removed from the cache.

Note

This procedure clears only dynamically discovered neighbors from the cache; it does not clear static neighbors. To clear static neighbors, see the

“Deleting Static Neighbors” section on page 7-26

.

Interface Configuration

To configure the remaining interfaces and enable traffic between two or more interfaces, perform the following steps:

Step 1

Step 2

To change the configuration of the interface in the Edit Interface dialog box, click

Edit

.

To enable traffic between two or more interfaces with the same security level, check the

Enable traffic between two or more interfaces with the same security level

check box.

Note

IP address-related fields are not available in transparent mode.

Step 3

Click

Next

to continue.

Outside Interface Configuration - PPPoE

To configure the outside interface by obtaining an IP address from a PPPoE server, perform the following steps:

Step 1

Step 2

Enter the name of the group. You must specify a group name to proceed.

In the User Authentication area, enter the following information:

•

The PPPoE username.

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7-27



Step 3

Step 4

Step 5

•

The PPPoE password.

•

Confirm the PPPoE password.

In the Authentication Method area, enter the following:

•

•

PAP is the default authentication method for PPPoE. You have the option of configuring CHAP or

MS-CHAP manually. The username and password are sent unencrypted using this method.

To select CHAP authentication, check the

CHAP

check box. CHAP does not prevent unauthorized access; it identifies the remote end. The access server then determines whether the user is allowed access.

•

To select MS-CHAP authentication for PPP connections between a computer using a Windows operating system and an access server, check the

MS-CHAP

check box.


•

•

To obtain an IP address using a PPPoE server, click the

Obtain IP Address using PPPoE

radio button.

To specify an IP address for an interface, click the


radio button.

–

–

Enter an IP address for an interface.

Enter or choose a subnet mask for an interface from the drop-down list.

•

To obtain the default route between the PPPoE server and the PPPoE client, click the


radio button.

Click

Next

to continue.

Outside Interface Configuration

Note


To configure the outside interface by specifying an IP address, or by obtaining one from a PPPoE or a

DHCP server, perform the following steps:

Step 1

Step 2

On the Interface Settings tab, do the following:

a.

b.

c.

Choose an interface from the drop-down list.

Add a name to a new interface or show the name associated with an existing interface.

d.

To activate the interface in privileged mode, check the

Enable interface

check box.

Specify the security level range for the interface from 0 to 100, with 100 assigned to the inside interface and 0 assigned to the outside interface. Perimeter interfaces can use any number between

1 and 99. Security levels between 0 and 100 for perimeter interfaces are not set by default.


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OL-20339-01


Feature History for the Startup Wizard

Step 3

Step 4

•

•

To obtain an IP address from a PPPoE server, click the

Use PPPoE

radio button.

To obtain an IP address from a DHCP server, click the

Use DHCP

radio button.

–

To obtain an IP address for the default gateway using DHCP, check the

Obtain default route using DHCP

check box.

On the IPv6 Interface Settings tab, do the following:

•

To enable the IPv6 interface, check the

Enable IPv6 for the Interface

check box.

•

•

To add an IPv6 interface address, check the

Add an IPv6 Address

check box.

Specify the IPv6 address and prefix length (for example, fe80:aabb::). Multiple addresses with prefixes are allowed; however, no two addresses can be repeated within the list of addresses.

–

To configure an address using the EUI 64-bit interface identifier format, check the

EUI 64

check box.

Click

Next

to continue.


Table 7-3


Table 7-3

Feature Name

Startup Wizard

Feature History for the Startup Wizard

Platform Releases

7.0(1)


This feature was introduced.

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7-29



7-30


OL-20339-01

Configuring Interfaces

C H A P T E R

8

This chapter describes how to configure interfaces, including Ethernet parameters, switch ports (for the

ASA 5505), VLAN subinterfaces, and IP addressing.

The procedure to configure interfaces varies depending on several factors: the ASA 5505 vs. other models; routed vs. transparent mode; and single vs. multiple mode. This chapter describes how to configure interfaces for each of these variables.

Note

If your adaptive security appliance has the default factory configuration, many interface parameters are already configured. This chapter assumes you do

not

have a factory default configuration, or that if you have a default configuration, that you need to change the configuration. For information about the factory default configurations, see the

“Factory Default Configurations” section on page 2-5

.


•

•

•

•

•

•

•

•

•

•

•

Information About Interfaces, page 8-1

Licensing Requirements for Interfaces, page 8-6



Starting Interface Configuration (ASA 5510 and Higher), page 8-9

Starting Interface Configuration (ASA 5505), page 8-16

Completing Interface Configuration (All Models), page 8-21

Allowing Same Security Level Communication, page 8-31

Enabling Jumbo Frame Support (ASA 5580, Multiple Mode), page 8-32

Monitoring Interfaces, page 8-32

Feature History for Interfaces, page 8-40

Information About Interfaces

This section describes adaptive security appliance interfaces and includes the following topics:

•

ASA 5505 Interfaces, page 8-2

•

•

ASA 5580 Interfaces, page 8-5

Auto-MDI/MDIX Feature, page 8-5

OL-20339-01


8-1

Chapter 8 Configuring Interfaces


•

•

•

Security Levels, page 8-5

Dual IP Stack, page 8-6

Management Interface (ASA 5510 and Higher), page 8-6

ASA 5505 Interfaces

This section describes the ports and interfaces of the ASA 5505 adaptive security appliance and includes the following topics:

•

Understanding ASA 5505 Ports and Interfaces, page 8-2

•

•

•

Maximum Active VLAN Interfaces for Your License, page 8-2

VLAN MAC Addresses, page 8-4

Power over Ethernet, page 8-4

Understanding ASA 5505 Ports and Interfaces

The ASA 5505 adaptive security appliance supports a built-in switch. There are two kinds of ports and interfaces that you need to configure:

•

•

Physical switch ports—The adaptive security appliance has 8 Fast Ethernet switch ports that forward traffic at Layer 2, using the switching function in hardware. Two of these ports are PoE ports. See the

“Power over Ethernet” section on page 8-4

for more information. You can connect these interfaces directly to user equipment such as PCs, IP phones, or a DSL modem. Or you can connect to another switch.

Logical VLAN interfaces—In routed mode, these interfaces forward traffic between VLAN networks at Layer 3, using the configured security policy to apply firewall and VPN services. In transparent mode, these interfaces forward traffic between the VLANs on the same network at Layer

2, using the configured security policy to apply firewall services. See the “Maximum Active VLAN

Interfaces for Your License” section for more information about the maximum VLAN interfaces.

VLAN interfaces let you divide your equipment into separate VLANs, for example, home, business, and Internet VLANs.

To segregate the switch ports into separate VLANs, you assign each switch port to a VLAN interface.

Switch ports on the same VLAN can communicate with each other using hardware switching. But when a switch port on VLAN 1 wants to communicate with a switch port on VLAN 2, then the adaptive security appliance applies the security policy to the traffic and routes or bridges between the two

VLANs.

Maximum Active VLAN Interfaces for Your License

In transparent firewall mode, you can configure the following VLANs depending on your license:

•

Base license—2 active VLANs.

•

Security Plus license—3 active VLANs, one of which must be for failover.

In routed mode, you can configure the following VLANs depending on your license: Base license

•

•

Base license—3 active VLANs. The third VLAN can only be configured to initiate traffic to one other VLAN. See

Figure 8-1


Security Plus license—20 active VLANs.

8-2


OL-20339-01



Note

An

active VLAN

is a VLAN with a

nameif

command configured.

With the Base license, the third VLAN can only be configured to initiate traffic to one other VLAN. See

Figure 8-1 for an example network where the Home VLAN can communicate with the Internet, but

cannot initiate contact with Business.

Figure 8-1 ASA 5505 Adaptive Security Appliance with Base License

Internet

ASA 5505 with Base License

Home

Business

With the Security Plus license, you can configure 20 VLAN interfaces, including a VLAN interface for failover and a VLAN interface as a backup link to your ISP. You can configure the backup interface to not pass through traffic unless the route through the primary interface fails. You can configure trunk ports to accommodate multiple VLANs per port.

Note

The ASA 5505 adaptive security appliance supports Active/Standby failover, but not Stateful Failover.

OL-20339-01


8-3



See

Figure 8-2 for an example network.

Figure 8-2 ASA 5505 Adaptive Security Appliance with Security Plus License

Backup ISP

Primary ISP

ASA 5505 with Security Plus

License

Failover

ASA 5505

DMZ

Failover Link

Inside

VLAN MAC Addresses

•

•

Routed firewall mode—All VLAN interfaces share a MAC address. Ensure that any connected switches can support this scenario. If the connected switches require unique MAC addresses, you can manually assign MAC addresses. See the

“Configuring Advanced Interface Parameters” section on page 8-26

.

Transparent firewall mode—Each VLAN has a unique MAC address. You can override the generated

MAC addresses if desired by manually assigning MAC addresses. See the “Configuring Advanced

Interface Parameters” section on page 8-26

.

Power over Ethernet

Ethernet 0/6 and Ethernet 0/7 support PoE for devices such as IP phones or wireless access points. If you install a non-PoE device or do not connect to these switch ports, the adaptive security appliance does not supply power to the switch ports.

If you shut down the switch port, you disable power to the device. Power is restored when you enable the portd. See the

“Configuring and Enabling Switch Ports as Access Ports” section on page 8-18

for more information about shutting down a switch port.

Monitoring Traffic Using SPAN

If you want to monitor traffic that enters or exits one or more switch ports, you can enable SPAN, also known as switch port monitoring. The port for which you enable SPAN (called the destination port) receives a copy of every packet transmitted or received on a specified source port. The SPAN feature lets you attach a sniffer to the destination port so you can monitor all traffic; without SPAN, you would have to attach a sniffer to every port you want to monitor. You can only enable SPAN for one destination port.


8-4 OL-20339-01



You can only enable SPAN monitoring using the Command Line Interface tool by entering the

switchport monitor

command. See the

switchport monitor

command in the


Command Reference


ASA 5580 Interfaces

The ASA 5580 adaptive security appliance supports multiple types of Ethernet interfaces including

Gigabit Ethernet and 10-Gigabit Ethernet speeds, and copper and fiber connectors. See the

Cisco ASA

5580 Adaptive Security Appliance Getting Started Guide

for detailed information about the interface adapters available for the ASA 5580 adaptive security appliance, and which slots support each adapter type.

Auto-MDI/MDIX Feature

For RJ-45 interfaces on the ASA 5500 series adaptive security appliance, the default auto-negotiation setting also includes the Auto-MDI/MDIX feature. Auto-MDI/MDIX eliminates the need for crossover cabling by performing an internal crossover when a straight cable is detected during the auto-negotiation phase. Either the speed or duplex must be set to auto-negotiate to enable Auto-MDI/MDIX for the interface. If you explicitly set both the speed and duplex to a fixed value, thus disabling auto-negotiation for both settings, then Auto-MDI/MDIX is also disabled. For Gigabit Ethernet, when the speed and duplex are set to 1000 and full, then the interface always auto-negotiates; therefore Auto-MDI/MDIX is always enabled and you cannot disable it.

Security Levels

Each interface must have a security level from 0 (lowest) to 100 (highest). For example, you should assign your most secure network, such as the inside host network, to level 100. While the outside network connected to the Internet can be level 0. Other networks, such as DMZs can be in between. You can assign interfaces to the same security level. See the

“Allowing Same Security Level Communication” section on page 8-31 for more information.

The level controls the following behavior:

•

Network access—By default, there is an implicit permit from a higher security interface to a lower security interface (outbound). Hosts on the higher security interface can access any host on a lower security interface. You can limit access by applying an access list to the interface.

If you enable communication for same security interfaces (see the

“Allowing Same Security Level

Communication” section on page 8-31

), there is an implicit permit for interfaces to access other interfaces on the same security level or lower.

•

•

Inspection engines—Some application inspection engines are dependent on the security level. For same security interfaces, inspection engines apply to traffic in either direction.

–

NetBIOS inspection engine—Applied only for outbound connections.

–

SQL*Net inspection engine—If a control connection for the SQL*Net (formerly OraServ) port exists between a pair of hosts, then only an inbound data connection is permitted through the adaptive security appliance.

Filtering—HTTP(S) and FTP filtering applies only for outbound connections (from a higher level to a lower level).

If you enable communication for same security interfaces, you can filter traffic in either direction.


OL-20339-01 8-5


Licensing Requirements for Interfaces

•

•

NAT control—When you enable NAT control, you must configure NAT for hosts on a higher security interface (inside) when they access hosts on a lower security interface (outside).

Without NAT control, or for same security interfaces, you can choose to use NAT between any interface, or you can choose not to use NAT. Keep in mind that configuring NAT for an outside interface might require a special keyword.

established

command—This command allows return connections from a lower security host to a higher security host if there is already an established connection from the higher level host to the lower level host.

If you enable communication for same security interfaces, you can configure

established

commands for both directions.

Dual IP Stack

The adaptive security appliance supports the configuration of both IPv6 and IPv4 on an interface. You do not need to enter any special commands to do so; simply enter the IPv4 configuration commands and

IPv6 configuration commands as you normally would. Make sure you configure a default route for both

IPv4 and IPv6.

Management Interface (ASA 5510 and Higher)

The management interface is a Fast Ethernet interface designed for management traffic only. You can, however, use it for through traffic if desired. In transparent firewall mode, you can use the management interface (for management purposes) in addition to the two interfaces allowed for through traffic. You can also add subinterfaces to the management interface to provide management in each security context for multiple context mode.

Note


management

interface to access the switch, instead of the data interface. This action causes a temporary traffic interruption; the adaptive security appliance will not re-update the MAC address table for packets from the switch to the data interface for at least 30 seconds for security reasons.

Licensing Requirements for Interfaces

The following table shows the licensing requirements for VLANs:

8-6


OL-20339-01



Model

ASA 5505

ASA 5510

ASA 5520

ASA 5540

ASA 5550

ASA 5580

Model

ASA 5505

All other models


Base License: 3 (2 regular zones and 1 restricted zone that can only communicate with 1 other zone)

Security Plus License: 20

Base License: 50

Security Plus License: 100

Base License: 150

Base License: 200

Base License: 250

Base License: 250

The following table shows the licensing requirements for VLAN trunks:


Base License: None.

Security Plus License: 8.

N/A




•

In multiple context mode, configure the physical interfaces in the system execution space according to the

“Starting Interface Configuration (ASA 5510 and Higher)” section on page 8-9 .

•

Then, configure the logical interface parameters in the context execution space according to the

“Completing Interface Configuration (All Models)” section on page 8-21

.


Transparent firewall mode allows only two interfaces to pass through traffic; however, on the ASA 5510 and higher adaptive security appliance, you can use the Management 0/0 or 0/1 interface (either the physical interface or a subinterface) as a third interface for management traffic. The mode is not configurable in this case and must always be management-only.


Do not finish configuring failover interfaces with the procedures in

“Completing Interface Configuration

(All Models)” section on page 8-21 . See the

“Configuring Active/Standby Failover” section on page 59-6

or the

“Configuring Active/Active Failover” section on page 60-8 to configure the failover and

state links. In multiple context mode, failover interfaces are configured in the system configuration.

IPv6 Guidelines

•

Supports IPv6.


OL-20339-01 8-7



•

In transparent mode on a per interface basis, you can only configure the link-local address; you configure the global address as the management address for the entire unit, but not per interface.

Because configuring the management global IP address automatically configures the link-local addresses per interface, the only IPv6 configuration you need to perform is to set the management

IP address according to the

“Configuring the IPv6 Address” section on page 9-16 .


Subinterfaces are not available for the ASA 5505 adaptive security appliance.


This section lists default settings for interfaces if you do not have a factory default configuration. For information about the factory default configurations, see the

“Factory Default Configurations” section on page 2-5

.

Default Security Level

The default security level is 0. If you name an interface “inside” and you do not set the security level explicitly, then the adaptive security appliance sets the security level to 100.

Note

If you change the security level of an interface, and you do not want to wait for existing connections to time out before the new security information is used, you can clear the connections using the

clear local-host

command.

Default State of Interfaces

The default state of an interface depends on the type and the context mode.

In multiple context mode, all allocated interfaces are enabled by default, no matter what the state of the interface is in the system execution space. However, for traffic to pass through the interface, the interface also has to be enabled in the system execution space. If you shut down an interface in the system execution space, then that interface is down in all contexts that share it.

In single mode or in the system execution space, interfaces have the following default states:

•

Physical interfaces and switch ports—Disabled.

•

•

Redundant Interfaces—Enabled. However, for traffic to pass through the redundant interface, the member physical interfaces must also be enabled.

Subinterfaces or VLANs—Enabled. However, for traffic to pass through the subinterface, the physical interface must also be enabled.

Default Speed and Duplex

•

By default, the speed and duplex for copper (RJ-45) interfaces are set to auto-negotiate.

•

The fiber interface for the ASA 5550 and the 4GE SSM has a fixed speed and does not support duplex, but you can set the interface to negotiate link parameters (the default) or not to negotiate.

•

For fiber interfaces for the ASA 5580, the speed is set for automatic link negotiation.

Default Connector Type

The ASA 5550 adaptive security appliance and the 4GE SSM for the ASA 5510 and higher adaptive security appliance include two connector types: copper RJ-45 and fiber SFP. RJ-45 is the default. You can configure the adaptive security appliance to use the fiber SFP connectors.


8-8 OL-20339-01


Starting Interface Configuration (ASA 5510 and Higher)

Default MAC Addresses

By default, the physical interface uses the burned-in MAC address, and all subinterfaces of a physical interface use the same burned-in MAC address.


This section includes tasks for starting your interface configuration for the ASA 5510 and higher.

Note

For multiple context mode, complete all tasks in this section in the system execution space. If you are not already in the system execution space , in the Configuration > Device List pane, double-click

System


For ASA 5505 configuration, see the

“Starting Interface Configuration (ASA 5505)” section on page 8-16

.


•

•

•

•

•

Task Flow for Starting Interface Configuration, page 8-9

Configuring a Redundant Interface, page 8-12

Enabling the Physical Interface and Configuring Ethernet Parameters, page 8-10

Configuring VLAN Subinterfaces and 802.1Q Trunking, page 8-14

Assigning Interfaces to Contexts and Automatically Assigning MAC Addresses (Multiple Context

Mode), page 8-16

Task Flow for Starting Interface Configuration

To start configuring interfaces, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

(Multiple context mode) Complete all tasks in this section in the system execution space. If you are not already in the System configuration mode, in the Configuration > Device List pane, double-click

System


Enable the physical interface, and optionally change Ethernet parameters. See the

“Enabling the Physical

Interface and Configuring Ethernet Parameters” section on page 8-10 .

Physical interfaces are disabled by default.

(Optional) Configure redundant interface pairs. See the

“Configuring a Redundant Interface” section on page 8-12

.

A logical redundant interface pairs an active and a standby physical interface. When the active interface fails, the standby interface becomes active and starts passing traffic.

(Optional) Configure VLAN subinterfaces. See the “Configuring VLAN Subinterfaces and 802.1Q

Trunking” section on page 8-14

.

(Multiple context mode only) Assign interfaces to contexts and automatically assign unique MAC addresses to context interfaces. See the

“Assigning Interfaces to Contexts and Automatically Assigning

MAC Addresses (Multiple Context Mode)” section on page 8-16 .

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8-9



Step 6

Complete the interface configuration according to the

“Completing Interface Configuration (All

Models)” section on page 8-21 .

Enabling the Physical Interface and Configuring Ethernet Parameters

This section describes how to:

•

Enable the physical interface

•

•

Set a specific speed and duplex (if available)

Enable pause frames for flow control (ASA 5580 10 Gigabit Ethernet only).

Prerequisites

For multiple context mode, complete this procedure in the system execution space. If you are not already in the System configuration mode, in the Configuration > Device List pane, double-click

System


Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

Depending on your context mode:

•

•

For single mode, choose the

Configuration > Device Setup > Interfaces

pane.

For multiple mode in the System execution space, choose the

Configuration > Context

Management > Interfaces

pane.

By default, all physical interfaces are listed.

Click a physical interface that you want to configure, and click

Edit

.

The Edit Interface dialog box appears.

To enable the interface, check the

Enable Interface

check box.

To add a description, enter text in the Description field.

The description can be up to 240 characters on a single line, without carriage returns. In the case of a failover or state link, the description is fixed as “LAN Failover Interface,” “STATE Failover Interface,” or “LAN/STATE Failover Interface,” for example. You cannot edit this description. The fixed description overwrites any description you enter here if you make this interface a failover or state link.

(Optional) To set the media type, duplex, and speed, or for the ASA 5580 10 Gigabit Ethernet interface, enable pause frames for flow control, click

Configure Hardware Properties

.

a.

If you have an ASA 5550 adaptive security appliance or a 4GE SSM, you can choose either

RJ-45

or

SFP

from the Media Type drop-down list.

b.

RJ-45 is the default.

To set the duplex for RJ-45 interfaces, choose

Full

,

Half

, or

Auto

, depending on the interface type, from the Duplex drop-down list.

c.

To set the speed, choose a value from the Speed drop-down list.

The speeds available depend on the interface type. For SFP interfaces, you can set the speed to

Negotiate or Nonegotiate. Negotiate (the default) enables link negotiation, which exchanges flow-control parameters and remote fault information. Nonegotiate does not negotiate link

8-10


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Starting Interface Configuration (ASA 5510 and Higher) d.

parameters. For RJ-45 interfaces on the ASA 5500 series adaptive security appliance, the default auto-negotiation setting also includes the Auto-MDI/MDIX feature. See the

“Auto-MDI/MDIX

Feature” section on page 8-5 .

For the ASA 5580 10 Gigabit Ethernet interfaces, to enable pause (XOFF) frames for flow control on 10 Gigabit Ethernet interfaces, check the

Enable Pause Frame

check box.

If you have a traffic burst, dropped packets can occur if the burst exceeds the buffering capacity of the FIFO buffer on the NIC and the receive ring buffers. Enabling pause frames for flow control can alleviate this issue. Pause (XOFF) and XON frames are generated automatically by the NIC hardware based on the FIFO buffer usage. A pause frame is sent when the buffer usage exceeds the

High Watermark. The default value is 128 KB; you can set it between 0 and 511. After a pause is sent, an XON frame can be sent when the buffer usage is reduced below the Low Watermark. By default, the value is 64 KB; you can set it between 0 and 511. The link partner can resume traffic after receiving an XON, or after the XOFF expires, as controlled by the Pause Time value in the pause frame. The default value is 26624; you can set it between 0 and 65535. If the buffer usage is consistently above the High Watermark, pause frames are sent repeatedly, controlled by the pause refresh threshold value.

To change the default values for the Low Watermark, High Watermark, and Pause Time, uncheck the

Use Default Values

check box.

Note

Only flow control frames defined in 802.3x are supported. Priority-based flow control is not supported.

Step 6 e.

Click

OK

to accept the Hardware Properties changes.

Click

OK

to accept the Interface changes.

What to Do Next

Optional Tasks:

•

•

Configure redundant interface pairs. See the

page 8-12

.

“Configuring a Redundant Interface” section on

Configure VLAN subinterfaces. See the “Configuring VLAN Subinterfaces and 802.1Q Trunking” section on page 8-14 .

Required Tasks:

•

For multiple context mode, assign interfaces to contexts and automatically assign unique MAC addresses to context interfaces. See the

“Assigning Interfaces to Contexts and Automatically

Assigning MAC Addresses (Multiple Context Mode)” section on page 8-16

.

•

For single context mode, complete the interface configuration. See the

“Completing Interface

Configuration (All Models)” section on page 8-21 .

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8-11



Configuring a Redundant Interface

A logical redundant interface consists of a pair of physical interfaces: an active and a standby interface.

When the active interface fails, the standby interface becomes active and starts passing traffic. You can configure a redundant interface to increase the adaptive security appliance reliability. This feature is separate from device-level failover, but you can configure redundant interfaces as well as failover if desired.

This section describes how to configure redundant interfaces and includes the following topics:

•

•

Configuring a Redundant Interface, page 8-12

Changing the Active Interface, page 8-14

Configuring a Redundant Interface

This section describes how to create a redundant interface. By default, redundant interfaces are enabled.


•

•

•

You can configure up to 8 redundant interface pairs.

All adaptive security appliance configuration refers to the logical redundant interface instead of the member physical interfaces.

Redundant interface delay values are configurable, but by default the adaptive security appliance will inherit the default delay values based on the physical type of its member interfaces.

•

•

For failover, follow these guidelines when adding member interfaces:

•

If you want to use a redundant interface for the failover or state link, then you must configure the redundant interface as part of the basic configuration on the secondary unit in addition to the primary unit.

•

The only configuration available to physical interfaces that are part of a redundant interface pair are physical parameters (set in the

“Enabling the Physical Interface and Configuring Ethernet

Parameters” section on page 8-10

).

If you shut down the active interface, then the standby interface becomes active.

•

•

If you use a redundant interface for the failover or state link, you must put a switch or hub between the two units; you cannot connect them directly. Without the switch or hub, you could have the active port on the primary unit connected directly to the standby port on the secondary unit.

You can monitor redundant interfaces for failover.

When the active interface fails over to the standby interface, this activity does not cause the redundant interface to appear to be failed when being monitored for device-level failover. Only when both physical interfaces fail does the redundant interface appear to be failed.

Redundant Interface MAC Address

The redundant interface uses the MAC address of the first physical interface that you add. If you change the order of the member interfaces in the configuration, then the MAC address changes to match the

MAC address of the interface that is now listed first. Alternatively, you can assign a MAC address to the redundant interface, which is used regardless of the member interface MAC addresses (see the


or the

“Assigning Interfaces to

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OL-20339-01



Contexts and Automatically Assigning MAC Addresses (Multiple Context Mode)” section on page 8-16

). When the active interface fails over to the standby, the same MAC address is maintained so that traffic is not disrupted.

Prerequisites

•

•

•

Both member interfaces must be of the same physical type. For example, both must be Ethernet.

You cannot add a physical interface to the redundant interface if you configured a name for it. You must first remove the name in the Configuration > Device Setup > Interfaces pane.


System


Caution

If you are using a physical interface already in your configuration, removing the name will clear any configuration that refers to the interface.

Detailed Steps

You can configure up to 8 redundant interface pairs. To configure a redundant interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8


•

•



pane.




pane.

Click

Add > Redundant Interface

.

The Add Redundant Interface dialog box appears.

In the Redundant ID field, enter an integer between 1 and 8.

From the Primary Interface drop-down list, choose the physical interface you want to be primary.

Be sure to pick an interface that does not have a subinterface and that has not already been allocated to a context.

From the Secondary Interface drop-down list, choose the physical interface you want to be secondary.

If the interface is not already enabled, check the


check box.

The interface is enabled by default. To disable it, uncheck the check box.

To add a description, enter text in the Description field.

The description can be up to 240 characters on a single line, without carriage returns. For multiple context mode, the system description is independent of the context description. In the case of a failover or state link, the description is fixed as “LAN Failover Interface,” “STATE Failover Interface,” or

“LAN/STATE Failover Interface,” for example. You cannot edit this description. The fixed description overwrites any description you enter here if you make this interface a failover or state link.

Click

OK

.

You return to the Interfaces pane.

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8-13



What to Do Next

Optional Task:

•

Configure VLAN subinterfaces. See the

“Configuring VLAN Subinterfaces and 802.1Q Trunking” section on page 8-14 .

Required Tasks:

•

•



Assigning MAC Addresses (Multiple Context Mode)” section on page 8-16 .

For single context mode, complete the interface configuration. See the “Completing Interface

Configuration (All Models)” section on page 8-21

.

Changing the Active Interface

By default, the active interface is the first interface listed in the configuration, if it is available. To view which interface is active, enter the following command in the Tools > Command Line Interface tool:

show interface redundant

number

detail | grep Member

For example:

show interface redundant1 detail | grep Member

Members GigabitEthernet0/3(Active), GigabitEthernet0/2

To change the active interface, enter the following command:

redundant-interface redundant

number

active-member

physical_interface

where the

redundant

number

argument is the redundant interface ID, such as

redundant1

.

The

physical_interface

is the member interface ID that you want to be active.

Configuring VLAN Subinterfaces and 802.1Q Trunking

Subinterfaces let you divide a physical or redundant interface into multiple logical interfaces that are tagged with different VLAN IDs. An interface with one or more VLAN subinterfaces is automatically configured as an 802.1Q trunk. Because VLANs allow you to keep traffic separate on a given physical interface, you can increase the number of interfaces available to your network without adding additional physical interfaces or adaptive security appliances. This feature is particularly useful in multiple context mode so that you can assign unique interfaces to each context.


•

•

Maximum subinterfaces—To determine how many VLAN subinterfaces are allowed for your platform, see the

“Licensing Requirements for Interfaces” section on page 8-6 .

Preventing untagged packets on the physical interface—If you use subinterfaces, you typically do not also want the physical interface to pass traffic, because the physical interface passes untagged packets. This property is also true for the active physical interface in a redundant interface pair.

Because the physical or redundant interface must be enabled for the subinterface to pass traffic, ensure that the physical or redundant interface does not pass traffic by not configuring a name for the interface. If you want to let the physical or redundant interface pass untagged packets, you can configure the name as usual. See the

“Completing Interface Configuration (All Models)” section on page 8-21 for more information about completing the interface configuration.


8-14 OL-20339-01



Prerequisites


System


Detailed Steps

To add a subinterface and assign a VLAN to it, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8


•



pane.

•




pane.

Click

Add > Interface

.

The Add Interface dialog box appears.

From the Hardware Port drop-down list, choose the physical interface to which you want to add the subinterface.



check box.

The interface is enabled by default. To disable it, uncheck the check box.

In the VLAN ID field, enter the VLAN ID between 1 and 4095.

Some VLAN IDs might be reserved on connected switches, so check the switch documentation for more information. For multiple context mode, you can only set the VLAN in the system configuration.

In the Subinterface ID field, enter the subinterface ID as an integer between 1 and 4294967293.

The number of subinterfaces allowed depends on your platform. You cannot change the ID after you set it.

(Optional) In the Description field, enter a description for this interface.

The description can be up to 240 characters on a single line, without carriage returns. For multiple context mode, the system description is independent of the context description. In the case of a failover or state link, the description is fixed as “LAN Failover Interface,” “STATE Failover Interface,” or

“LAN/STATE Failover Interface,” for example. You cannot edit this description. The fixed description overwrites any description you enter here if you make this interface a failover or state link.

Click

OK

.

You return to the Interfaces pane.

What to Do Next

•

•



Assigning MAC Addresses (Multiple Context Mode)” section on page 8-16

.

For single context mode, complete the interface configuration. See the



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8-15


Starting Interface Configuration (ASA 5505)

Assigning Interfaces to Contexts and Automatically Assigning MAC Addresses

(Multiple Context Mode)

To complete the configuration of interfaces in the system execution space, perform the following tasks that are documented in

Chapter 6, “Configuring Multiple Context Mode”

:

•

•

To assign interfaces to contexts, see the

“Configuring a Security Context” section on page 6-17

.

(Optional) To automatically assign unique MAC addresses to context interfaces, see the


.

The MAC address is used to classify packets within a context. If you share an interface, but do not have unique MAC addresses for the interface in each context, then the destination IP address is used to classify packets. Alternatively, you can manually assign MAC addresses within the context according to the

“Configuring Advanced Interface Parameters” section on page 8-26 .

What to Do Next

Complete the interface configuration. See the

“Completing Interface Configuration (All Models)” section on page 8-21 .


This section includes tasks for starting your interface configuration for the ASA 5505 adaptive security appliance, including creating VLAN interfaces and assigning them to switch ports. See the

“Understanding ASA 5505 Ports and Interfaces” section on page 8-2


For ASA 5510 and higher configuration, see the

“Starting Interface Configuration (ASA 5510 and

Higher)” section on page 8-9 .


•

Task Flow for Starting Interface Configuration, page 8-16

•

•

•

Configuring VLAN Interfaces, page 8-17

Configuring and Enabling Switch Ports as Access Ports, page 8-18

Configuring and Enabling Switch Ports as Trunk Ports, page 8-19

Task Flow for Starting Interface Configuration

To configure interfaces in single mode, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Configure VLAN interfaces. See the

“Configuring VLAN Interfaces” section on page 8-17

.

Configure and enable switch ports as access ports. See the “Configuring and Enabling Switch Ports as

Access Ports” section on page 8-18 .

(Optional for Security Plus licenses) Configure and enable switch ports as trunk ports. See the

“Configuring and Enabling Switch Ports as Trunk Ports” section on page 8-19

.

Complete the interface configuration according to the

“Completing Interface Configuration (All

Models)” section on page 8-21 .

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OL-20339-01



Configuring VLAN Interfaces

This section describes how to configure VLAN interfaces. For more information about ASA 5505 interfaces, see the

“ASA 5505 Interfaces” section on page 8-2

.

Detailed Steps

Note

If you enabled Easy VPN, you cannot add or delete VLAN interfaces, nor can you edit the security level or interface name. We suggest that you finalize your interface configuration before you enable Easy

VPN.

Step 1

Step 2

Step 3

Choose the


pane.

On the Interfaces tab, click

Add

.

The Add Interface dialog box appears with the General tab selected.

In the Available Switch Ports pane, choose a switch port, and click

Add

.

You see the following message:

“switchport

is associated with

name

interface. Adding it to this interface, will remove it from

name

interface. Do you want to continue?”

Click

OK

to add the switch port.

You will always see this message when adding a switch port to an interface; switch ports are assigned to the VLAN 1 interface by default even when you do not have any configuration.

Repeat for any other switch ports that you want to carry this VLAN.

Note

Removing a switch port from an interface essentially just reassigns that switch port to VLAN 1, because the default VLAN interface for switch ports is VLAN 1.

Step 4

Click the

Advanced

tab.

Note

You receive an error message about setting the IP address. You can either set the IP address and other parameters now, or you can finish configuring the VLAN and switch ports by clicking

Yes

, and later set the IP address and other parameters according to the



Step 5

Step 6

In the VLAN ID field, enter the VLAN ID for this interface, between 1 and 4090.

If you do not want to assign the VLAN ID, ASDM assigns one for you randomly.

(Optional for the Base license) To allow this interface to be the third VLAN by limiting it from initiating contact to one other VLAN, in the Block Traffic From this Interface to drop-down list, choose the VLAN to which this VLAN interface cannot initiate traffic.

With the Base license, you can only configure a third VLAN if you use this command to limit it.

For example, you have one VLAN assigned to the outside for Internet access, one VLAN assigned to an inside business network, and a third VLAN assigned to your home network. The home network does not need to access the business network, so you can use this option on the home VLAN; the business network can access the home network, but the home network cannot access the business network.

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8-17



If you already have two VLAN interfaces configured with a name, be sure to configure this setting before setting the name on the third interface; the adaptive security appliance does not allow three fully functioning VLAN interfaces with the Base license on the ASA 5505 adaptive security appliance.

Note

If you upgrade to the Security Plus license, you can remove this option and achieve full functionality for this interface. If you leave this option enabled, this interface continues to be limited even after upgrading.

To configure the MAC address and MTU, see the


.

Step 7

Click

OK

.

What to Do Next

Configure the switch ports. See the

“Configuring and Enabling Switch Ports as Access Ports” section on page 8-18 and the

“Configuring and Enabling Switch Ports as Trunk Ports” section on page 8-19 .

Configuring and Enabling Switch Ports as Access Ports

By default (with no configuration), all switch ports are shut down, and assigned to VLAN 1. To assign a switch port to a single VLAN, configure it as an access port. To create a trunk port to carry multiple

VLANs, see the

“Configuring and Enabling Switch Ports as Trunk Ports” section on page 8-19 . If you

have a factory default configuration, see the

“ASA 5505 Default Configuration” section on page 2-6

to check if you want to change the default interface settings according to this procedure.

For more information about ASA 5505 interfaces, see the

“ASA 5505 Interfaces” section on page 8-2

.

Caution

The ASA 5505 adaptive security appliance does not support Spanning Tree Protocol for loop detection in the network. Therefore you must ensure that any connection with the adaptive security appliance does not end up in a network loop.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Choose the


pane.

Click the

Switch Ports

tab.

Click the switch port you want to edit.

The Edit Switch Port dialog box appears.

To enable the switch port, check the

Enable SwitchPort

check box.

In the Mode and VLAN IDs area, click the

Access

radio button.

In the VLAN ID field, enter the VLAN ID associated with this switch port. The VLAN ID can be between 1 and 4090.

8-18


OL-20339-01



Step 7

Step 8

Step 9

Step 10

By default, the VLAN ID is derived from the VLAN interface configuration you completed in


(on the Configuration > Device Setup > Interfaces

> Interfaces > Add/Edit Interface dialog box). You can change the VLAN assignment in this dialog box.

Be sure to apply the change to update the VLAN configuration with the new information. If you want to specify a VLAN that has not yet been added, we suggest you add the VLAN according to the

“Configuring VLAN Interfaces” section on page 8-17 rather than specifying it in this dialog box; in

either case, you need to add the VLAN according to the


and assign the switch port to it.

(Optional) To prevent the switch port from communicating with other protected switch ports on the same

VLAN, check the

Isolated

check box.

This option prevents the switch port from communicating with other protected switch ports on the same

VLAN. You might want to prevent switch ports from communicating with each other if the devices on those switch ports are primarily accessed from other VLANs, you do not need to allow intra-VLAN access, and you want to isolate the devices from each other in case of infection or other security breach.

For example, if you have a DMZ that hosts three web servers, you can isolate the web servers from each other if you apply the Protected option to each switch port. The inside and outside networks can both communicate with all three web servers, and vice versa, but the web servers cannot communicate with each other.

(Optional) From the Duplex drop-down list, choose

Full

,

Half

, or

Auto

.

The Auto setting is the default. If you set the duplex to anything other than Auto on PoE ports Ethernet

0/6 or 0/7, then Cisco IP phones and Cisco wireless access points that do not support IEEE 802.3af will not be detected and supplied with power.

(Optional) From the Speed drop-down list, choose

10

,

100

, or

Auto

.

The Auto setting is the default. If you set the speed to anything other than Auto on PoE ports Ethernet


Click

OK

.

What to Do Next

If you want to configure a switch port as a trunk port, see the

“Configuring and Enabling Switch Ports as Trunk Ports” section on page 8-19 .

To complete the interface configuration, see the


Configuring and Enabling Switch Ports as Trunk Ports

This procedure describes how to create a trunk port that can carry multiple VLANs using 802.1Q tagging. Trunk mode is available only with the Security Plus license.

To create an access port, where an interface is assigned to only one VLAN, see the

“Configuring and

Enabling Switch Ports as Access Ports” section on page 8-18 .

For more information about ASA 5505 interfaces, see the

“ASA 5505 Interfaces” section on page 8-2 .

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8-19



Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Choose the


pane.

Click the

Switch Ports

tab.

Click the switch port you want to edit.

The Edit Switch Port dialog box appears.

To enable the switch port, check the

Enable SwitchPort

check box.

In the Mode and VLAN IDs area, click the

Trunk

radio button.

In the VLAN IDs field, enter the VLAN IDs associated with this switch port, separated by commas. The

VLAN ID can be between 1 and 4090.

You can include the native VLAN in this field, but it is not required; the native VLAN is passed whether it is included in this field or not.

This switch port cannot pass traffic until you assign at least one VLAN to it, native or non-native.

If the VLANs are already in your configuration, after you apply the change, the Configuration > Device

Setup > Interfaces > Interfaces tab shows this switch port added to each VLAN. If you want to specify a VLAN that has not yet been added, we suggest you add the VLAN according to the

“Configuring

VLAN Interfaces” section on page 8-17 rather than specifying it in this dialog box; in either case, you

need to add the VLAN according to the


and assign the switch port to it.

To configure the native VLAN, check the

Configure Native VLAN

check box, and enter the VLAN ID in the Native VLAN ID field. The VLAN ID can be between 1 and 4090.

Packets on the native VLAN are not modified when sent over the trunk. For example, if a port has

VLANs 2, 3 and 4 assigned to it, and VLAN 2 is the native VLAN, then packets on VLAN 2 that egress the port are not modified with an 802.1Q header. Frames which ingress (enter) this port and have no

802.1Q header are put into VLAN 2.

Each port can only have one native VLAN, but every port can have either the same or a different native

VLAN.

(Optional) To prevent the switch port from communicating with other protected switch ports on the same

VLAN, check the

Isolated

check box.

This option prevents the switch port from communicating with other protected switch ports on the same

VLAN. You might want to prevent switch ports from communicating with each other if the devices on those switch ports are primarily accessed from other VLANs, you do not need to allow intra-VLAN access, and you want to isolate the devices from each other in case of infection or other security breach.

For example, if you have a DMZ that hosts three web servers, you can isolate the web servers from each other if you apply the Protected option to each switch port. The inside and outside networks can both communicate with all three web servers, and vice versa, but the web servers cannot communicate with each other.

(Optional) From the Duplex drop-down list, choose

Full

,

Half

, or

Auto

.

The Auto setting is the default. If you set the duplex to anything other than Auto on PoE ports Ethernet


(Optional) From the Speed drop-down list, choose

10

,

100

, or

Auto

.

The Auto setting is the default. If you set the speed to anything other than Auto on PoE ports Ethernet


8-20


OL-20339-01


Completing Interface Configuration (All Models)

Step 11

Click

OK

.

What to Do Next

To complete the interface configuration, see the



This section includes tasks to complete the interface configuration for all models.

Note

For multiple context mode, complete the tasks in this section in the context execution space. In the

Configuration > Device List pane, double-click the context name under the active device IP address.


•

•

•

•

Configuring General Interface Parameters, page 8-22

Configuring Advanced Interface Parameters, page 8-26

Configuring IPv6 Addressing, page 8-27

Configuring the Link-Local Address on an Interface (Transparent Firewall Mode), page 8-30

Task Flow for Completing Interface Configuration

Step 1

Step 2

Step 3

Step 4

Step 5

Complete the procedures in the “Starting Interface Configuration (ASA 5510 and Higher)” section on page 8-9

or the

“Starting Interface Configuration (ASA 5505)” section on page 8-16 .

(Multiple context mode) In the Configuration > Device List pane, double-click the context name under the active device IP address.

Configure general interface parameters, including the interface name, security level, and IPv4 address.

See the

“Configuring General Interface Parameters” section on page 8-22 .

For transparent mode, you do not configure IP addressing per interface, except for the management-only interface (see the

“Information About the Management Interface” section on page 8-22 ). You do need to

configure the other parameters in this section, however. To set the global management address for transparent mode, see the

“Configuring the IPv4 Address” section on page 9-15 .

(Optional) Configure the MAC address and the MTU. See the

“Configuring Advanced Interface

Parameters” section on page 8-26 .

(Optional) Configure IPv6 addressing. See the “Configuring IPv6 Addressing” section on page 8-27

.

For transparent mode, you do not configure IP addressing per interface, except for the management-only interface (see the

“Information About the Management Interface” section on page 8-22 ). This section

includes how to set the link-local address in transparent mode, but this task is usually not required. To

set the global management address for transparent mode, see the “Configuring the IPv6 Address” section on page 9-16 .

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8-21



Configuring General Interface Parameters

This procedure describes how to set the name, security level, IPv4 address and other options.

For the ASA 5510 and higher, you must configure interface parameters for the following interface types:

•

•

Physical interfaces

VLAN subinterfaces

•

Redundant interfaces

For the ASA 5505, you must configure interface parameters for the following interface types:

•

VLAN interfaces


•

•

•

•

•

For the ASA 5550 adaptive security appliance, for maximum throughput, be sure to balance your traffic over the two interface slots; for example, assign the inside interface to slot 1 and the outside interface to slot 0.

For information about security levels, see the “Security Levels” section on page 8-5 .

If you are using failover, do not use this procedure to name interfaces that you are reserving for failover and Stateful Failover communications. See the

“Configuring Active/Standby Failover” section on page 59-6

or the

“Configuring Active/Active Failover” section on page 60-8

to configure the failover and state links.

In routed firewall mode, set the IP address for all interfaces.

In transparent firewall mode, do not set the IP address for each interface, but rather set it for the whole adaptive security appliance or context. The exception is for the Management 0/0 or 0/1 management-only interface, which does not pass through traffic. To set the transparent firewall mode whole adaptive security appliance or context management IP address, see the

“Setting the

Management IP Address for a Transparent Firewall” section on page 9-14

. To set the IP address of the Management 0/0 or 0/1 interface or subinterface, use this procedure.

Restrictions

PPPoE is not supported in multiple context mode or transparent firewall mode.

Information About the Management Interface

The ASA 5510 and higher adaptive security appliance includes a dedicated management interface called

Management 0/0 or Management 0/1, depending on your model, which is meant to support traffic to the adaptive security appliance. However, you can configure any interface to be a management-only interface. Also, for Management 0/0 or 0/1, you can disable management-only mode so the interface can pass through traffic just like any other interface.

Transparent firewall mode allows only two interfaces to pass through traffic; however, on the ASA 5510 and higher adaptive security appliance, you can use the Management 0/0 or 0/1 interface (either the physical interface or a subinterface) as a third interface for management traffic. The mode is not configurable in this case and must always be management-only.

Prerequisites

•

Complete the procedures in the

“Starting Interface Configuration (ASA 5510 and Higher)” section on page 8-9

or the

“Starting Interface Configuration (ASA 5505)” section on page 8-16 .

8-22


OL-20339-01



•

In multiple context mode, complete this procedure in the context execution space. To change from the system to a context configuration, in the Configuration > Device List pane, double-click the context name under the active device IP address.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Choose the


pane.

For the ASA 5505, the Interfaces tab shows by default.

Choose the interface row, and click

Edit

.

The Edit Interface dialog box appears with the General tab selected.

In the Interface Name field, enter a name up to 48 characters in length.

In the Security level field, enter a level between 0 (lowest) and 100 (highest).

See the

“Security Levels” section on page 8-5


(Optional) To set this interface as a management-only interface, check the

Dedicate this interface to management-only

check box.

Through traffic is not accepted on a management-only interface. For the ASA 5510 and higher, see the

“Information About the Management Interface” section on page 8-22 for more information.



check box.

To set the IP address, one of the following options.

Note

For use with failover, you must set the IP address and standby address manually; DHCP and

PPPoE are not supported. Set the standby IP addresses on the Configuration > Device

Management > High Availability > Failover > Interfaces tab

In transparent firewall mode, do not set the IP address for each interface, but rather set it for the whole adaptive security appliance or context. The exception is for the Management 0/0 or 0/1 management-only interface, which does not pass through traffic.

•

•

To set the IP address manually, click the

Use Static IP

radio button and enter the IP address and mask.

To obtain an IP address from a DHCP server, click the

Obtain Address via DHCP

radio button.

a.

(Optional) To force a MAC address to be stored inside a DHCP request packet for option 61 instead of the default internally-generated string, click the

Use MAC Address

radio button.

b.

Some ISPs expect option 61 to be the interface MAC address. If the MAC address is not included in the DHCP request packet, then an IP address will not be assigned.

(Optional) To obtain the default route from the DHCP server, check

Obtain Default Route

Using DHCP

.

c.

(Optional) To assigns an administrative distance to the learned route, enter a value between 1 and 255 in the DHCP Learned Route Metric field. If this field is left blank, the administrative distance for the learned routes is 1.

d.

(Optional) To enable tracking for DHCP-learned routes, check

Enable Tracking for DHCP

Learned Routes

. Set the following values:

Track ID—A unique identifier for the route tracking process. Valid values are from 1 to 500.

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8-23



Track IP Address—Enter the IP address of the target being tracked. Typically, this would be the

IP address of the next hop gateway for the route, but it could be any network object available off of that interface.

Note

Route tracking is only available in single, routed mode.

Step 8

•

SLA ID—A unique identifier for the SLA monitoring process. Valid values are from 1 to

2147483647.

Monitor Options—Click this button to open the Route Monitoring Options dialog box. In the

Route Monitoring Options dialog box you can configure the parameters of the tracked object monitoring process.

e.

(Optional) To renew the lease, click

Renew DHCP Lease

.

(Single, routed mode only) To obtain an IP address using PPPoE, check

Use PPPoE

.

a.

In the Group Name field, specify a group name.

b.

In the PPPoE Username field, specify the username provided by your ISP.

c.

In the PPPoE Password field, specify the password provided by your ISP.

d.

In the Confirm Password field, retype the password.

e.

For PPP authentication, click either the

PAP

,

CHAP

, or

MSCHAP

radio button.

PAP passes cleartext username and password during authentication and is not secure. With

CHAP, the client returns the encrypted [challenge plus password], with a cleartext username in response to the server challenge. CHAP is more secure than PAP, but it does not encrypt data.

MSCHAP is similar to CHAP but is more secure because the server stores and compares only encrypted passwords rather than cleartext passwords as in CHAP. MSCHAP also generates a key for data encryption by MPPE.

f.

(Optional) To store the username and password in Flash memory, check the

Store Username and Password in Local Flash

check box.

The adaptive security appliance stores the username and password in a special location of

NVRAM. If an Auto Update Server sends a

clear configure

command to the adaptive security appliance, and the connection is then interrupted, the adaptive security appliance can read the username and password from NVRAM and re-authenticate to the Access Concentrator.

g.

(Optional) To display the PPPoE IP Address and Route Settings dialog box where you can choose addressing and tracking options, click

IP Address and Route Settings

. See the

“PPPoE

IP Address and Route Settings” section on page 8-25 for more information.

(Optional) In the Description field, enter a description for this interface.

The description can be up to 240 characters on a single line, without carriage returns. In the case of a failover or state link, the description is fixed as “LAN Failover Interface,” “STATE Failover Interface,” or “LAN/STATE Failover Interface,” for example. You cannot edit this description. The fixed description overwrites any description you enter here if you make this interface a failover or state link.

Note

(ASA 5510 and higher) For information about the Configure Hardware Properties button, see the

“Enabling the Physical Interface and Configuring Ethernet Parameters” section on page 8-10 .

Step 9

Click

OK

.

8-24


OL-20339-01



What to Do Next

•

•

(Optional) Configure the MAC address and the MTU. See the

“Configuring Advanced Interface

Parameters” section on page 8-26 .


.

PPPoE IP Address and Route Settings

The Configuration > Interfaces > Add/Edit Interface > General > PPPoE IP Address and Route Settings

> PPPoE IP Address and Route Settings dialog box lets you choose addressing and tracking options for

PPPoE connections.

Fields

•

IP Address area—Lets you choose between Obtaining an IP address using PPP or specifying an IP address, and contains the following fields:

–

Obtain IP Address using PPP—Select to enable the adaptive security appliance to use PPP to get an IP address.

•

–

Specify an IP Address—Specify an IP address and mask for the adaptive security appliance to use instead of negotiating with the PPPoE server to assign an address dynamically.

Route Settings Area—Lets you configure route and tracking settings and contains the following fields:

–

–

Obtain default route using PPPoE—Sets the default routes when the PPPoE client has not yet established a connection. When using this option, you cannot have a statically defined route in the configuration.

PPPoE learned route metric—Assigns an administrative distance to the learned route. Valid values are from 1 to 255. If this field is left blank, the administrative distance for the learned routes is 1.

Enable tracking—Check this check box to enable route tracking for PPPoE-learned routes.

Note

Route tracking is only available in single, routed mode.

–

–

–

–

–

–

–

Primary Track—Select this option to configure the primary PPPoE route tracking.

Track ID—A unique identifier for the route tracking process. Valid values are from 1 to 500.

Track IP Address—Enter the IP address of the target being tracked. Typically, this would be the

IP address of the next hop gateway for the route, but it could be any network object available off of that interface.

SLA ID—A unique identifier for the SLA monitoring process. Valid values are from 1 to

2147483647.

Monitor Options—Click this button to open the Route Monitoring Options dialog box. In the

Route Monitoring Options dialog box you can configure the parameters of the tracked object monitoring process.

Secondary Track—Select this option to configure the secondary PPPoE route tracking.

Secondary Track ID—A unique identifier for the route tracking process. Valid values are from

1 to 500.

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8-25



Configuring Advanced Interface Parameters

This section describes how to configure MAC addresses for interfaces and how to set the MTU.

Information About MAC Addresses

By default, the physical interface uses the burned-in MAC address, and all subinterfaces of a physical interface use the same burned-in MAC address. A redundant interface uses the MAC address of the first physical interface that you add. If you change the order of the member interfaces in the configuration, then the MAC address changes to match the MAC address of the interface that is now listed first. If you assign a MAC address to the redundant interface using this command, then it is used regardless of the member interface MAC addresses.

In multiple context mode, if you share an interface between contexts, you can assign a unique MAC address to the interface in each context. This feature lets the adaptive security appliance easily classify packets into the appropriate context. Using a shared interface without unique MAC addresses is possible, but has some limitations. See the

“How the Security Appliance Classifies Packets” section on page 6-3

for more information. You can assign each MAC address manually, or you can automatically generate

MAC addresses for shared interfaces in contexts. See the

“Automatically Assigning MAC Addresses to

Context Interfaces” section on page 6-19 to automatically generate MAC addresses. If you automatically

generate MAC addresses, you can use this procedure to override the generated address.

For single context mode, or for interfaces that are not shared in multiple context mode, you might want to assign unique MAC addresses to subinterfaces. For example, your service provider might perform access control based on the MAC address.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Choose the


pane.

For the ASA 5505, the Interfaces tab shows by default.

Choose the interface row, and click

Edit

.


Click the

Advanced

tab.

To set the MTU or to enable jumbo frame support (ASA 5580 only), enter the value in the MTU field, between 300 and 65,535 bytes.

The default is 1500 bytes.

•

•

For the ASA 5580 in single mode—If you enter a value for any interface that is greater than 1500, then you enable jumbo frame support automatically for all interfaces. If you set the MTU for all interfaces back to a value under 1500, then jumbo frame support is disabled.

For the ASA 5580 in multiple mode—If you enter a value for any interface that is greater than 1500, then be sure to enable jumbo frame support in the system configuration. See the

“Enabling Jumbo

Frame Support (ASA 5580, Multiple Mode)” section on page 8-32

.

Note

Enabling or disabling jumbo frame support requires you to reboot the security appliance.

A jumbo frame is an Ethernet packet larger than the standard maximum of 1518 bytes (including Layer

2 header and FCS), up to 9216 bytes. Jumbo frames require extra memory to process, and assigning more memory for jumbo frames might limit the maximum use of other features, such as access lists.

8-26


OL-20339-01



Step 5

Step 6

To manually assign a MAC address to this interface, enter a MAC address in the Active Mac Address field in H.H.H format, where H is a 16-bit hexadecimal digit.

For example, the MAC address 00-0C-F1-42-4C-DE would be entered as 000C.F142.4CDE. The first two bytes of a manual MAC address cannot be A2 if you also want to use auto-generated MAC addresses.

If you use failover, enter the standby MAC address in the Standby Mac Address field. If the active unit fails over and the standby unit becomes active, the new active unit starts using the active MAC addresses to minimize network disruption, while the old active unit uses the standby address.

What to Do Next


.

Configuring IPv6 Addressing

This section describes how to configure IPv6 addressing. For more information about IPv6, see the

“Information About IPv6 Support” section on page 18-8 and the

“IPv6 Addresses” section on page A-5 .

For transparent mode, use this section for the Management 0/0 or 0/1 interface. To configure the global

IPv6 management address for transparent mode, see the

“Configuring the IPv6 Address” section on page 9-16

. If you do not configure a management address, you can configure the link-local addresses in transparent mode according to the

“Configuring the Link-Local Address on an Interface (Transparent

Firewall Mode)” section on page 8-30 .

Information About IPv6 Addressing

When you configure an IPv6 address on an interface, you can assign one or several IPv6 addresses to the interface at one time, such as an IPv6 link-local address and a global address. However, at a minimum, you must configure a link-local address.

Every IPv6-enabled interface must include at least one link-local address. When you configure a global address, a link-local addresses is automatically configured on the interface, so you do not also need to specifically configure a link-local address. These link-local addresses can only be used to communicate with other hosts on the same physical link.

When IPv6 is used over Ethernet networks, the Ethernet MAC address can be used to generate the 64-bit interface ID for the host. This is called the EUI-64 address. Because MAC addresses use 48 bits, additional bits must be inserted to fill the 64 bits required. The last 64 bits are used for the interface ID.

For example, FE80::/10 is a link-local unicast IPv6 address type in hexadecimal format.

Information About Duplicate Address Detection

During the stateless autoconfiguration process, duplicate address detection (DAD) verifies the uniqueness of new unicast IPv6 addresses before the addresses are assigned to interfaces (the new addresses remain in a tentative state while duplicate address detection is performed). Duplicate address detection is performed first on the new link-local address. When the link local address is verified as unique, then duplicate address detection is performed all the other IPv6 unicast addresses on the interface.

Duplicate address detection is suspended on interfaces that are administratively down. While an interface is administratively down, the unicast IPv6 addresses assigned to the interface are set to a pending state. An interface returning to an administratively up state restarts duplicate address detection for all of the unicast IPv6 addresses on the interface.


OL-20339-01 8-27



When a duplicate address is identified, the state of the address is set to DUPLICATE, the address is not used, and the following error message is generated:

%ASA-4-325002:

Duplicate address

ipv6_address

/

MAC_address

on

interface

If the duplicate address is the link-local address of the interface, the processing of IPv6 packets is disabled on the interface. If the duplicate address is a global address, the address is not used. However, all configuration commands associated with the duplicate address remain as configured while the state of the address is set to DUPLICATE.

If the link-local address for an interface changes, duplicate address detection is performed on the new link-local address and all of the other IPv6 address associated with the interface are regenerated

(duplicate address detection is performed only on the new link-local address).

The adaptive security appliance uses neighbor solicitation messages to perform duplicate address detection. By default, the number of times an interface performs duplicate address detection is 1.

Information About Modified EUI-64 Interface IDs

RFC 3513: Internet Protocol Version 6 (IPv6) Addressing Architecture requires that the interface identifier portion of all unicast IPv6 addresses, except those that start with binary value 000, be 64 bits long and be constructed in Modified EUI-64 format. The adaptive security appliance can enforce this requirement for hosts attached to the local link.

When this command is enabled on an interface, the source addresses of IPv6 packets received on that interface are verified against the source MAC addresses to ensure that the interface identifiers use the

Modified EUI-64 format. If the IPv6 packets do not use the Modified EUI-64 format for the interface identifier, the packets are dropped and the following system log message is generated:

%ASA-3-325003: EUI-64 source address check failed.

The address format verification is only performed when a flow is created. Packets from an existing flow are not checked. Additionally, the address verification can only be performed for hosts on the local link.

Packets received from hosts behind a router will fail the address format verification, and be dropped, because their source MAC address will be the router MAC address and not the host MAC address.

Restrictions

The adaptive security appliance does not support IPv6 anycast addresses.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

Choose the

Configuration

>

Device Setup

>

Interfaces

pane.

Choose an interface, and click

Edit

.


Click the

IPv6

tab.

(Optional) To enforce the use of Modified EUI-64 format interface identifiers in IPv6 addresses on a local link, check the

Enforce EUI-64

check box.

If the interface identifiers do not conform to the modified EUI-64 format, an error message appears. See the

“Information About Modified EUI-64 Interface IDs” section on page 8-28


Configure the global IPv6 address using one of the following methods.

8-28


OL-20339-01



OL-20339-01

Step 6

Note

If you do not want to configure a global IPv6 address, you can configure the link-local addresses either automatically by checking the

Enable IPv6

check box, or manually by entering a value in the Link-local address field in the Interface IPv6 Addresses area. A link-local address should start with FE8, FE9, FEA, or FEB, for example fe80::20d:88ff:feee:6a82.

See the

“IPv6

Addresses” section on page A-5 for more information about IPv6 addressing.

If you configure a global IPv6 address (or manually configure a link-local address), checking or unchecking the

Enable IPv6

check box does not affect how IPv6 operates; IPv6 continues to be enabled.

•

•

Stateless autoconfiguration—In the Interface IPv6 Addresses area, check the


check box.

Enabling stateless autconfiguration on the interface configures IPv6 addresses based upon prefixes received in Router Advertisement messages. A link-local address, based on the Modified EUI-64 interface ID, is automatically generated for the interface when stateless autoconfiguration is enabled.

Manual configuration—To manually configure a global IPv6 address:

a.


Add

.

b.


In the Address/Prefix Length field, enter the global IPv6 address and the IPv6 prefix length. For example, 2001:0DB8::BA98:0:3210/48. See the

“IPv6 Addresses” section on page A-5 for

more information about IPv6 addressing.

c.

(Optional) To use the Modified EUI-64 interface ID in the low order 64 bits of the address, check the

EUI-64

check box.

(Optional) In the top area, customize the IPv6 configuration by configuring the following options:

•

DAD Attempts—This setting configures the number of consecutive neighbor solicitation messages that are sent on an interface while DAD is performed on IPv6 addresses. Valid values are from 0 to

600. A zero value disables DAD processing on the specified interface. The default is one message.

• d.

Click

OK

.

•

NS Interval—Enter the neighbor solicitation message interval. The neighbor solicitation message requests the link-layer address of a target node. Valid values are from 1000 to 3600000 milliseconds.

The default is 1000 milliseconds.

Reachable Time—Enter the amount of time in seconds that a remote IPv6 node is considered reachable after a reachability confirmation event has occurred. Valid values are from 0 to 3600000 milliseconds. The default is zero. A configured time enables the detection of unavailable neighbors.

Shorter times enable detection more quickly; however, very short configured times are not recommended in normal IPv6 operation.

•

•

RA Lifetime—Enter the amount of time that IPv6 router advertisement transmissions are considered valid. Valid values are from 0 to 9000 seconds. The default is 1800 seconds. Router advertisement transmissions include a preference level and a lifetime field for each advertised router address.

These transmissions provide route information and indicate that the router is still operational to network hosts.

RA Interval—Enter the interval between IPv6 router advertisement transmissions. Valid values are from 3 to 1800 seconds. The default is 200 seconds. To list the router advertisement transmission interval in milliseconds, check the


check box. Valid values are from

500 to 1800000 milliseconds.


8-29



Step 7

Step 8

Step 9

•

(Optional) To configure which IPv6 prefixes are included in IPv6 router advertisements, complete the following.

By default, prefixes configured as addresses on an interface are advertised in router advertisements. If you configure prefixes for advertisement using this area, then only these prefixes are advertised.

a.

To allow the generation of addresses for hosts, make sure that the Suppress RA check box is unchecked. This is the default setting if IPv6 unicast routing is enabled. To prevent the generation of IPv6 router advertisement transmissions, check the

Suppress RA

check box.


Add

.


b.

c.

In the Address/Prefix Length field, enter the IPv6 address with the prefix length. To configure settings that apply to all prefixes, check the

Default Values

check box instead of entering an

Address.



check box.

d.

e.

f.

(Optional) To indicate that the specified prefix is not used for on-link determination, check the

Off-link

check box.

(Optional) To indicate to hosts on the local link that the specified prefix cannot be used for IPv6 autoconfiguration, check the


check box.

In the Prefix Lifetime area, choose one of the following:

–

Lifetime Duration—Specify the following:

A valid lifetime for the prefix in seconds from the drop-down list. This setting is the amount of time that the specified IPv6 prefix is advertised as being valid. The maximum value represents infinity. Valid values are from 0 to 4294967295. The default is 2592000 (30 days).

A preferred lifetime for the prefix from the drop-down list. This setting is the amount of time that the specified IPv6 prefix is advertised as being preferred. The maximum value represents infinity. Valid values are from 0 to 4294967295. The default setting is 604800 (seven days).

–

Lifetime Expiration Date—Specify the following:



Click

OK

.

You return to the Edit Interface dialog box.

Click

OK

.

You return to the Configuration > Device Setup > Interfaces pane.

Configuring the Link-Local Address on an Interface (Transparent Firewall Mode)

If you only need to configure a link-local address and are not going to assign any other IPv6 addresses, you have the option of manually defining the link-local address.

To assign a link-local address to an interface, perform the following steps:

Step 1

Choose the


pane.

8-30


OL-20339-01


Allowing Same Security Level Communication

Step 2

Step 3

Step 4

Step 5

Step 6

Select an interface, and click

Edit

.


Click the

IPv6

tab.

(Optional) To enforce the use of Modified EUI-64 format interface identifiers in IPv6 addresses on a local link, check the

Enforce EUI-64

check box.

If the interface identifiers do not conform to the modified EUI-64 format, an error message appears. See the

“Information About Modified EUI-64 Interface IDs” section on page 8-28 for more information.

To set the link-local address, enter an address in the Link-local address field.

A link-local address should start with FE8, FE9, FEA, or FEB, for example fe80::20d:88ff:feee:6a82.

See the

“IPv6 Addresses” section on page A-5 for more information about IPv6 addressing.

Click

OK

.

Allowing Same Security Level Communication

By default, interfaces on the same security level cannot communicate with each other, and packets cannot enter and exit the same interface. This section describes how to enable inter-interface communication when interfaces are on the same security level, and how to enable intra-interface communication.

Information About Inter-Interface Communication

Allowing interfaces on the same security level to communicate with each other provides the following benefits:

•

You can configure more than 101 communicating interfaces.

If you use different levels for each interface and do not assign any interfaces to the same security level, you can configure only one interface per level (0 to 100).

You want traffic to flow freely between all same security interfaces without access lists.

•

If you enable same security interface communication, you can still configure interfaces at different security levels as usual.

Information About Intra-Interface Communication

Intra-interface communication might be useful for VPN traffic that enters an interface, but is then routed out the same interface. The VPN traffic might be unencrypted in this case, or it might be reencrypted for another VPN connection. For example, if you have a hub and spoke VPN network, where the security appliance is the hub, and remote VPN networks are spokes, for one spoke to communicate with another spoke, traffic must go into the security appliance and then out again to the other spoke.

Note

All traffic allowed by this feature is still subject to firewall rules. Be careful not to create an asymmetric routing situation that can cause return traffic not to traverse the adaptive security appliance.

Restrictions

This feature is only available in routed firewall mode.


OL-20339-01 8-31


Enabling Jumbo Frame Support (ASA 5580, Multiple Mode)

Detailed Steps

To disable these settings, use the

no

form of the command.

•

•

To enable interfaces on the same security level to communicate with each other, from the

Configuration > Interfaces pane, check

Enable traffic between two or more interfaces which are configured with same security level

.

To enable communication between hosts connected to the same interface, check


.

Enabling Jumbo Frame Support (ASA 5580, Multiple Mode)

A jumbo frame is an Ethernet packet larger than the standard maximum of 1518 bytes (including Layer

2 header and FCS), up to 9216 bytes. You can enable support for jumbo frames for all interfaces by increasing the amount of memory to process Ethernet frames. Assigning more memory for jumbo frames might limit the maximum use of other features, such as access lists.

Prerequisites

Note

Other platform models do not support jumbo frames.

In multiple context mode, set this option in the system execution space. In single mode, setting the MTU larger than 1500 bytes automatically enables jumbo frames.

Detailed Steps

To enable jumbo frame support, choose the

Configuration > Context Management > Interfaces pane

, and click the

Enable jumbo frame support

check box.

Note

Changes in this setting require you to reboot the adaptive security appliance.

Be sure to set the MTU for each interface that needs to transmit jumbo frames to a higher value than the default 1500; for example, set the value to 9000. See the

“Configuring Advanced Interface Parameters” section on page 8-26 . Set the MTU within each context.

Monitoring Interfaces


•

ARP Table, page 8-33

•

•

•

•

•

•

DHCP, page 8-33

MAC Address Table, page 8-35

Dynamic ACLs, page 8-36

Interface Graphs, page 8-36

PPPoE Client, page 8-39

Interface Connection, page 8-39


8-32 OL-20339-01



ARP Table

The Monitoring > Interfaces > ARP Table pane displays the ARP table, including static and dynamic entries. The ARP table includes entries that map a MAC address to an IP address for a given interface.

Fields

•

Interface—Lists the interface name associated with the mapping.

•

IP Address—Shows the IP address.

•

•

•

•

•

MAC Address—Shows the MAC address.

Proxy ARP—Displays Yes if proxy ARP is enabled on the interface. Displays No if proxy ARP is not enabled on the interface.

Clear—Clears the dynamic ARP table entries. Static entries are not cleared.

Refresh—Refreshes the table with current information from the adaptive security appliance and updates Last Updated date and time.

Last Updated—

Display only

. Shows the date and time the display was updated.

DHCP

The adaptive security appliance lets you monitor DHCP status, including the addresses assigned to clients, the lease information for a adaptive security appliance interface, and DHCP statistics.

DHCP Server Table

The Monitoring > Interfaces > DHCP > DHCP Server Table lists the IP addresses assigned to DHCP clients.

•

•

•

Fields

•

IP Address—Shows the IP address assigned to the client.

•

•

Client-ID—Shows the client MAC address or ID.

Lease Expiration—Shows the date that the DHCP lease expires. The lease indicates how long the client can use the assigned IP address. Remaining time is also specified in the number of seconds and is based on the timestamp in the Last Updated display-only field.

Number of Active Leases—Shows the total number of DHCP leases.

Refresh—Refreshes the information from the adaptive security appliance.

Last Updated—Shows when the data in the table was last updated.

DHCP Client Lease Information

If you obtain the adaptive security appliance interface IP address from a DHCP server, the Monitoring >

Interfaces > DHCP > DHCP Server Table > DHCP Client Lease Information pane shows information about the DHCP lease.

OL-20339-01


8-33



Fields

•

Select an interface—Lists the adaptive security appliance interfaces. Choose the interface for which you want to view the DHCP lease. If an interface has multiple DHCP leases, then choose the interface and IP address pair you want to view.

•

Attribute and Value—Lists the attributes and values of the interface DHCP lease.

–

–

Temp IP addr—

Display only

. The IP address assigned to the interface.

Temp sub net mask—

Display only

. The subnet mask assigned to the interface.

–

–

DHCP lease server—

Display only

. The DHCP server address.

state—

Display only

. The state of the DHCP lease, as follows:

Initial—The initialization state, where the security appliance begins the process of acquiring a lease. This state is also shown when a lease ends or when a lease negotiation fails.

Selecting—The security appliance is waiting to receive DHCPOFFER messages from one or more DHCP servers, so it can choose one.

Requesting—The security appliance is waiting to hear back from the server to which it sent its request.

Purging—The security appliance is removing the lease because of an error.

Bound—The security appliance has a valid lease and is operating normally.

Renewing—The security appliance is trying to renew the lease. It regularly sends

DHCPREQUEST messages to the current DHCP server, and waits for a reply.

Rebinding—The security appliance failed to renew the lease with the original server, and now sends DHCPREQUEST messages until it gets a reply from any server or the lease ends.

Holddown—The security appliance started the process to remove the lease.

–

Releasing—The security appliance sends release messages to the server indicating that the IP address is no longer needed.

Lease—

Display only

. The length of time, specified by the DHCP server, that the interface can use this IP address.

–

–

Renewal—

Display only

. The length of time until the interface automatically attempts to renew this lease.

Rebind—

Display only

. The length of time until the security appliance attempts to rebind to a

DHCP server. Rebinding occurs if the security appliance cannot communicate with the original

DHCP server, and 87.5 percent of the lease time has expired. The security appliance then attempts to contact any available DHCP server by broadcasting DHCP requests.

–

–

Next timer fires after—

Display only

. The number of seconds until the internal timer triggers.

Retry count—

Display only

. If the security appliance is attempting to establish a lease, this field shows the number of times the security appliance tried sending a DHCP message. For example, if the security appliance is in the Selecting state, this value shows the number of times the security appliance sent discover messages. If the security appliance is in the Requesting state, this value shows the number of times the security appliance sent request messages.

–

–

Client-ID—

Display only

. The client ID used in all communication with the server.

Proxy—

Display only

. Specifies if this interface is a proxy DHCP client for VPN clients, True or False.

–

Hostname—

Display only

. The client hostname.

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DHCP Statistics

The Monitoring > Interfaces > DHCP > DHCP Statistics pane shows statistics for the DHCP server feature.

Fields

•

Message Type—Lists the DHCP message types sent or received:

–

–

BOOTREQUEST

DHCPDISCOVER

–

–

–

–

DHCPREQUEST

DHCPDECLINE

DHCPRELEASE

DHCPINFORM

•

•

•

•

•

•

•

•

–

–

–

–

BOOTREPLY

DHCPOFFER

DHCPACK

DHCPNAK

Count—Shows the number of times a specific message was processed.

Direction—Shows if the message type is Sent or Received.

Total Messages Received—Shows the total number of messages received by the adaptive security appliance.

Total Messages Sent—Shows the total number of messages sent by the adaptive security appliance.

Counter—Shows general statistical DHCP data, including the following:

–

DHCP UDP Unreachable Errors

–

–

DHCP Other UDP Errors

Address Pools

–

–

Automatic Bindings

Expired Bindings

–

Malformed Messages

Value—Shows the number of each counter item.

Refresh—Updates the DHCP table listings.

Last Updated—Shows when the data in the tables was last updated.

MAC Address Table

The Monitoring > Interfaces > MAC Address Table pane shows the static and dynamic MAC address entries. See the

“MAC Address Table” section on page 8-35

for more information about the MAC address table and adding static entries.

Fields

•

Interface—Shows the interface name associated with the entry.

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8-35



•

•

•

•

MAC Address—Shows the MAC address.

Type—Shows if the entry is static or dynamic.

Age—Shows the age of the entry, in minutes. To set the timeout, see the

“MAC Address Table” section on page 8-35 .

Refresh—Refreshes the table with current information from the adaptive security appliance.

Dynamic ACLs

The Monitoring > Interfaces > Dynamic ACLs pane shows a table of the Dynamic ACLs, which are functionally identical to the user-configured ACLs except that they are created, activated and deleted automatically by the adaptive security appliance. These ACLs do not show up in the configuration and are only visible in this table. They are identified by the “(dynamic)” keyword in the ACL header.

When you choose an ACL in this table, the contents of the ACL are shown in the bottom text field.

Fields

•

ACL—Shows the name of the dynamic ACL.

•

Element Count—Shows the number of elements in the ACL

•

Hit Count—Shows the total hit count for all of the elements in the ACL.

Interface Graphs

The Monitoring > Interfaces > Interface Graphs pane lets you view interface statistics in graph or table form. If an interface is shared among contexts, the adaptive security appliance shows only statistics for the current context. The number of statistics shown for a subinterface is a subset of the number of statistics shown for a physical interface.

Fields

•

Available Graphs for—Lists the types of statistics available for monitoring. You can choose up to four types of statistics to show in one graph window. You can open multiple graph windows at the same time.

–

Byte Counts—Shows the number of bytes input and output on the interface.

–

–

Packet Counts—Shows the number of packets input and output on the interface.

Packet Rates—Shows the rate of packets input and output on the interface.

–

–

Bit Rates—Shows the bit rate for the input and output of the interface.

Drop Packet Count—Shows the number of packets dropped on the interface.

These additional statistics display for physical interfaces:

–

Buffer Resources—Shows the following statistics:

Overruns—The number of times that the adaptive security appliance was incapable of handing received data to a hardware buffer because the input rate exceeded the adaptive security appliance capability to handle the data.

Underruns—The number of times that the transmitter ran faster than the adaptive security appliance could handle.

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–

–

–

–

No Buffer—The number of received packets discarded because there was no buffer space in the main system. Compare this with the ignored count. Broadcast storms on Ethernet networks are often responsible for no input buffer events.

Packet Errors—Shows the following statistics:

CRC—The number of Cyclical Redundancy Check errors. When a station sends a frame, it appends a CRC to the end of the frame. This CRC is generated from an algorithm based on the data in the frame. If the frame is altered between the source and destination, the adaptive security appliance notes that the CRC does not match. A high number of CRCs is usually the result of collisions or a station transmitting bad data.

Frame—The number of frame errors. Bad frames include packets with an incorrect length or bad frame checksums. This error is usually the result of collisions or a malfunctioning Ethernet device.

Input Errors—The number of total input errors, including the other types listed here. Other input-related errors can also cause the input error count to increase, and some datagrams might have more than one error; therefore, this sum might exceed the number of errors listed for the other types.

Runts—The number of packets that are discarded because they are smaller than the minimum packet size, which is 64 bytes. Runts are usually caused by collisions. They might also be caused by poor wiring and electrical interference.

Giants—The number of packets that are discarded because they exceed the maximum packet size. For example, any Ethernet packet that is greater than 1518 bytes is considered a giant.

Deferred—For FastEthernet interfaces only. The number of frames that were deferred before transmission due to activity on the link.

Miscellaneous—Shows statistics for received broadcasts.

Collision Counts—For FastEthernet interfaces only. Shows the following statistics:

Output Errors—The number of frames not transmitted because the configured maximum number of collisions was exceeded. This counter should only increment during heavy network traffic.

Collisions—The number of messages retransmitted due to an Ethernet collision (single and multiple collisions). This usually occurs on an overextended LAN (Ethernet or transceiver cable too long, more than two repeaters between stations, or too many cascaded multiport transceivers). A packet that collides is counted only once by the output packets.

Late Collisions—The number of frames that were not transmitted because a collision occurred outside the normal collision window. A late collision is a collision that is detected late in the transmission of the packet. Normally, these should never happen. When two Ethernet hosts try to talk at once, they should collide early in the packet and both back off, or the second host should see that the first one is talking and wait. If you get a late collision, a device is jumping in and trying to send the packet on the Ethernet while the adaptive security appliance is partly finished sending the packet. The adaptive security appliance does not resend the packet, because it may have freed the buffers that held the first part of the packet. This is not a real problem because networking protocols are designed to cope with collisions by resending packets.

However, late collisions indicate a problem exists in your network. Common problems are large repeated networks and Ethernet networks running beyond the specification.

Input Queue—Shows the number of packets in the input queue, the current and the maximum, including the following statistics:

Hardware Input Queue—The number of packets in the hardware queue.

Software Input Queue—The number of packets in the software queue.


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•

•

•

•

–

Output Queue—Shows the number of packets in the output queue, the current and the maximum, including the following statistics:

Hardware Output Queue—The number of packets in the hardware queue.

Software Output Queue—The number of packets in the software queue.

–

Drop Packet Queue—Shows the number of packets dropped.

Add—Adds the selected statistic type to the selected graph window.

Remove—Removes the selected statistic type from the selected graph window. This button name changes to Delete if the item you are removing was added from another panel, and is not being returned to the Available Graphs pane.

Show Graphs—Shows the graph window name to which you want to add a statistic type. If you have a graph window already open, a new graph window is listed by default. If you want to add a statistic type to an already open graph, choose the open graph window name. The statistics already included on the graph are shown in the Selected Graphs pane, to which you can add additional types. Graph windows are named for ASDM followed by the interface IP address and the name “Graph”.

Subsequent graphs are named “Graph (2)” and so on.

Selected Graphs—Shows the statistic types you want to show in the selected graph window. You an include up to four types.

–

Show Graphs—Shows the graph window or updates the graph with additional statistic types if added.

Graph/Table

The Monitoring > Interfaces > Interface Graphs > Graph/Table window shows a graph for the selected statistics. The Graph window can show up to four graphs and tables at a time. By default, the graph or table displays the real-time statistics. If you enable History Metrics (see the

“Enabling History Metrics” section on page 9-13)

, you can view statistics for past time periods.

Fields

•

View—Sets the time period for the graph or table. To view any time period other than real-time, enable History Metrics (see the

“Enabling History Metrics” section on page 9-13)

. The data is updated according to the specification of the following options:

–

–

Real-time, data every 10 sec

Last 10 minutes, data every 10 sec

–

–

Last 60 minutes, data every 1 min

Last 12 hours, data every 12 min

•

•

–

Last 5 days, data every 2 hours

Export—Exports the graph in comma-separated value format. If there is more than one graph or table on the Graph window, the Export Graph Data dialog box appears. Choose one or more of the graphs and tables listed by checking the box next to the name.

Print—Prints the graph or table. If there is more than one graph or table on the Graph window, the

Print Graph dialog box appears. Choose the graph or table you want to print from the Graph/Table

Name list.

8-38


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•

Bookmark—Opens a browser window with a single link for all graphs and tables on the Graphs window, as well as individual links for each graph or table. You can then copy these URLs as bookmarks in your browser. ASDM does not have to be running when you open the URL for a graph; the browser launches ASDM and then displays the graph.

PPPoE Client

The Monitoring > Interfaces > PPPoE Client > PPPoE Client Lease Information pane displays information about current PPPoE connections.

Fields

Select a PPPoE interface—Select an interface that you want to view PPPoE client lease information.

Refresh—loads the latest PPPoE connection information from the adaptive security appliance for display.

Interface

Connection

The Monitoring > Interfaces >

interface

connection node in the Monitoring > Interfaces tree only appears if static route tracking is configured. If you have several routes tracked, there will be a node for each interface that contains a tracked route.

See the following for more information about the route tracking information available:

•

•

Track Status for, page 8-39

Monitoring Statistics for, page 8-39

Track Status for

The Monitoring > Interfaces > interface connection > Track Status for for pane displays information about the the tracked object.

Fields

•

Tracked Route—

Display only

. Displays the route associated with the tracking process.

•

Route Statistics—

Display only

. Displays the reachability of the object, when the last change in reachability occurred, the operation return code, and the process that is performing the tracking.

Monitoring Statistics for

The Monitoring > Interfaces > interface connection > Monitoring Statistics for pane displays statistics for the SLA monitoring process.

Fields

•

SLA Monitor ID—

Display only

. Displays the ID of the SLA monitoring process.

•

SLA statistics—

Display only

. Displays SLA monitoring statistics, such as the last time the process was modified, the number of operations attempted, the number of operations skipped, and so on.

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8-39


Feature History for Interfaces



Table 8-1 Feature History for Interfaces

Feature Name

Increased VLANs

Increased VLANs

Gigabit Ethernet Support for the ASA 5510

Security Plus License

Native VLAN support for the ASA 5505

Releases

7.0(5)


Increased the following limits:

•

ASA5510 Base license VLANs from 0 to 10.

•

•

ASA5510 Security Plus license VLANs from 10 to 25.

ASA5520 VLANs from 25 to 100.

7.2(2)

7.2(3)

•

ASA5540 VLANs from 100 to 200.

The maximum number of VLANs for the Security Plus license on the ASA 5505 adaptive security appliance was increased from 5 (3 fully functional; 1 failover; one restricted to a backup interface) to 20 fully functional interfaces. In addition, the number of trunk ports was increased from 1 to 8. Now there are 20 fully functional interfaces, you do not need to use the backup interface command to cripple a backup ISP interface; you can use a fully-functional interface for it. The backup interface command is still useful for an Easy VPN configuration.

VLAN limits were also increased for the ASA 5510 adaptive security appliance (from 10 to 50 for the Base license, and from 25 to 100 for the Security Plus license), the ASA 5520 adaptive security appliance (from 100 to

150), the ASA 5550 adaptive security appliance (from 200 to 250).

The ASA 5510 adaptive security appliance now supports

GE (Gigabit Ethernet) for port 0 and 1 with the Security

Plus license. If you upgrade the license from Base to

Security Plus, the capacity of the external Ethernet0/0 and

Ethernet0/1 ports increases from the original FE (Fast

Ethernet) (100 Mbps) to GE (1000 Mbps). The interface names will remain Ethernet 0/0 and Ethernet 0/1.

7.2(4)/8.0(4) You can now include the native VLAN in an ASA 5505 trunk port.


Setup > Interfaces > Switch Ports > Edit Switch Port.

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Table 8-1 Feature History for Interfaces (continued)

Feature Name

Jumbo packet support for the ASA 5580

Releases

8.1(1)

Increased VLANs for the ASA 5580

Support for Pause Frames for Flow Control on the ASA 5580 10 Gigabit Ethernet Interfaces

8.1(2)

8.2(2)


The Cisco ASA 5580 supports jumbo frames. A jumbo frame is an Ethernet packet larger than the standard maximum of 1518 bytes (including Layer 2 header and

FCS), up to 9216 bytes. You can enable support for jumbo frames for all interfaces by increasing the amount of memory to process Ethernet frames. Assigning more memory for jumbo frames might limit the maximum use of other features, such as access lists.


Setup > Interfaces > Add/Edit Interface > Advanced.

The number of VLANs supported on the ASA 5580 are increased from 100 to 250.

You can now enable pause (XOFF) frames for flow control.

The following screens were modified: (Single Mode)

Configuration > Device Setup > Interfaces > Add/Edit

Interface > General, (Multiple Mode, System)

Configuration > Interfaces > Add/Edit Interface.

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8-42


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C H A P T E R

9

Configuring Basic Settings

This chapter describes how to configure basic settings on your adaptive security appliance that are typically required for a functioning configuration. This chapter includes the following sections:

•

Configuring the Hostname, Domain Name, and Passwords, page 9-1

•

•

•

•

•

Setting the Date and Time, page 9-2

Configuring HTTP Redirect, page 9-5

Configuring the Master Passphrase, page 9-6

Configuring the DNS Server, page 9-10

•

•

•

Defining ASDM Preferences, page 9-11

Using the ASDM Assistant, page 9-13

Enabling History Metrics, page 9-13

Setting the Management IP Address for a Transparent Firewall, page 9-14

Configuring the Hostname, Domain Name, and Passwords

The Configuration > Device Setup > Device Name/Password pane lets you set the hostname and domain name for the adaptive security appliance and set the enable and telnet passwords.

The hostname appears in the command line prompt, and if you establish sessions to multiple devices, the hostname helps you keep track of where you enter commands. The hostname is also used in system messages.

For multiple context mode, the hostname that you set in the system execution space appears in the command line prompt for all contexts. The hostname that you optionally set within a context does not appear in the command line; it can be used for a banner.

The adaptive security appliance appends the domain name as a suffix to unqualified names. For example, if you set the domain name to “example.com,” and specify a syslog server by the unqualified name of

“jupiter,” then the security appliance qualifies the name to “jupiter.example.com.”

The Telnet Password sets the login password. By default, it is “cisco.” Although this area is called Telnet

Password, this password applies to Telnet and SSH access. The login password lets you access EXEC mode if you connect to the adaptive security appliance using a Telnet or SSH session. (If you configure user authentication for Telnet or SSH access, then each user has their own password, and this login password is not used.)


9-1 OL-20339-01

Chapter 9 Configuring Basic Settings

Setting the Date and Time

The enable password lets you access privileged EXEC mode after you log in. Also, this password is used to access ASDM as the default user, which is blank. The default user shows as “enable_15” in the User

Accounts pane. (If you configure user authentication for enable access, then each user has their own password, and this enable password is not used. In addition, you can configure authentication for

HTTP/ASDM access.)

Fields

The Hostname and Domain Name area contains the following fields:

•

•

Hostname—Sets the hostname. The default hostname depends on your platform.

Domain Name—Sets the domain name. The default domain name is default.domain.invalid.

The Enable Password area contains the following fields. In multiple context mode, the Enable Password area only appears in contexts; it does not appear in the system execution space.

•

Change the privileged mode password—Lets you change the enable password.

•

•

Old Password—Enter the old password.

New Password—Enter the new password.

•

Confirm New Password—Confirm the new password.

The Telnet Password area contains the following fields.

In multiple context mode, the Telnet Password area only appears in contexts; it does not appear in the system execution space.

•

•

•

•

Change the password to access the platform console—Lets you change the login password.

Old Password—Enter the old password.

New Password—Enter the new password.

Confirm New Password—Confirm the new password.


This section describes how to set the date and time, either manually or dynamically using an NTP server.

Time derived from an NTP server overrides any time set manually. This section also describes how to set the time zone and daylight saving time date range.

Note

In multiple context mode, set the time in the system configuration only.


•

•

Setting the Date and Time Using an NTP Server, page 9-3

Setting the Date and Time Manually, page 9-5

9-2


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Setting the Date and Time Using an NTP Server

To obtain the date and time from an NTP server, perform the following steps.

Detailed Steps


The Configuration > Device Setup > System Time > NTP NTP pane lets you define NTP servers to dynamically set the time on the adaptive security appliance. The time displays in the status bar at the bottom of the main ASDM pane.

Time derived from an NTP server overrides any time set manually in the Clock pane.

NTP is used to implement a hierarchical system of servers that provide a precisely synchronized time among network systems. This kind of accuracy is required for time-sensitive operations, such as validating CRLs, which include a precise time stamp. You can configure multiple NTP servers. The adaptive security appliance chooses the server with the lowest stratum—a measure of how reliable the data is.

Fields

•

NTP Server List—Shows defined NTP servers.

–

IP Address—Shows the NTP server IP address.

–

–

–

–

Interface—Specifies the outgoing interface for NTP packets, if configured. The system does not include any interfaces, so it uses the admin context interfaces. If the interface is blank, then the adaptive security appliance uses the default admin context interface according to the routing table.

Preferred?—Shows whether this NTP server is a preferred server, Yes or No. NTP uses an algorithm to determine which server is the most accurate and synchronizes to that one. If servers are of similar accuracy, then the preferred server is used. However, if a server is significantly more accurate than the preferred one, the adaptive security appliance uses the more accurate one. For example, the adaptive security appliance uses a more accurate server over a less accurate server that is preferred.

Key Number—Shows the authentication key ID number.

Trusted Key?—Shows if the key is a trusted key, Yes or No. The key must be trusted for authentication to work.

•

•

•

•

Enable NTP Authentication—Enables authentication for all servers.

Add—Adds an NTP server.

Edit—Edits an NTP server.

Delete—Deletes and NTP server.

Add/Edit NTP Server Configuration

The Configuration > Device Setup > System Time > NTP > Add/Edit NTP Server Configuration dialog box lets you add or edit an NTP server.

Fields

•

IP Address—Sets the NTP server IP address.

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9-3



•

•

•

Preferred—Sets this server as a preferred server. NTP uses an algorithm to determine which server is the most accurate and synchronizes to that one. If servers are of similar accuracy, then the preferred server is used. However, if a server is significantly more accurate than the preferred one, the adaptive security appliance uses the more accurate one. For example, the adaptive security appliance uses a more accurate server over a less accurate server that is preferred.

Interface—Sets the outgoing interface for NTP packets, if you want to override the default interface according to the routing table. The system does not include any interfaces, so it uses the admin context interfaces. If you intend to change the admin context (thus changing the available interfaces), you should choose

None

(the default interface) for stability.

Authentication Key—Sets the authentication key attributes if you want to use MD5 authentication for communicating with the NTP server.

–

–

Key Number—Sets the key ID for this authentication key. The NTP server packets must also use this key ID. If you previously configured a key ID for another server, you can select it in the list; otherwise, type a number between 1 and 4294967295.

Trusted—Sets this key as a trusted key. You must select this box for authentication to work.

–

–

Key Value—Sets the authentication key as a string up to 32 characters in length.

Reenter Key Value—Validates the key by ensuring that you enter the key correctly two times.

9-4


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Configuring HTTP Redirect

Setting the Date and Time Manually

The Configuration > Device Setup > System Time > Clock pane lets you manually set the date and time for the adaptive security appliance. The time displays in the status bar at the bottom of the main ASDM pane.

In multiple context mode, you can set the time in the system configuration only.

To dynamically set the time using an NTP server, see the

Configuring the Master Passphrase

pane;

time derived from an NTP server overrides any time set manually in the Clock pane.

Fields

•

Time Zone—Sets the time zone as GMT plus or minus the appropriate number of hours. If you select the Eastern Time, Central Time, Mountain Time, or Pacific Time zone, then the time adjusts automatically for daylight savings time, from 2:00 a.m. on the second Sunday in March to 2:00 a.m. on the first Sunday in November.

Note

Changing the time zone on the adaptive security appliance may drop the connection to intelligent SSMs.

•

•

•

Date—Sets the date. Click the Date drop-down list to display a calendar. Then navigate to the correct date using the following methods:

–

–

Click the name of the month to display a list of months. Click the desired month. The calendar updates to that month.

Click the year to change the year. You can use the up and down arrows to scroll through the years, or you can type a year in the entry field.

–

–

Click the arrows to the right and left of the month and year display to scroll the calendar forward and backwards one month at a time.

Click a day on the calendar to set the date.

Time—Sets the time on a 24-hour clock.

–

hh, mm, and ss boxes—Sets the hour, minutes, and seconds.

Update Display Time—Updates the time shown in the bottom right corner of the ASDM pane. The current time updates automatically every ten seconds.

Configuring HTTP Redirect

The HTTP Redirect table displays each interface on the adaptive security appliance, shows whether it is configured to redirect HTTP connections to HTTPS, and the port number from which it redirects those connections.

Note

To redirect HTTP, the interface requires an access list that permits HTTP. Otherwise, the interface cannot listen to the HTTP port.

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9-5



The Configuration > Device Management > Advanced > HTTP Redirect > Edit pane lets you change the

HTTP redirect setting of an interface or the port from which it redirects HTTP connections, select the interface in the table and click

Edit

. You can also double-click an interface. The Edit HTTP/HTTPS

Settings dialog box opens.

Edit HTTP/HTTPS Settings

The Edit HTTP/HTTPS Settings dialog box lets you change the HTTP redirect setting of an interface or the port number.

Fields

The Edit HTTP/HTTPS Settings dialog box includes the following fields:

•

Interface—Identifies the interface on which the adaptive security appliance redirects or does not redirect HTTP requests to HTTPS.

•

•

Redirect HTTP to HTTPS—Check to redirect HTTP requests to HTTPS, or uncheck to not redirect

HTTP requests to HTTPS.

HTTP Port—Identifies the port from which the interface redirects HTTP connections. By default it listens to port 80.


•

•

•

This section describes how to configure the master passphrase. This section includes the following topics:

•

•

Information About the Master Passphrase, page 9-6

Licensing Requirements for the Master Passphrase, page 9-7

•

•


Adding or Changing the Master Passphrase, page 9-7

Disabling the Master Passphrase, page 9-8

Recovering the Master Passphrase, page 9-9

Feature History for the Master Passphrase, page 9-9

Information About the Master Passphrase

•

•

•

The master passphrase feature allows you to securely store plain text passwords in encrypted format. The master passphrase provides a key that is used to universally encrypt or mask all passwords, without changing any functionality. Passwords that take advantage of this feature include:

OSPF

EIGRP

•

VPN load balancing

VPN (remote access and site-to-site)

•

•

Failover

AAA servers


9-6 OL-20339-01


•

•

•

Logging

Shared licenses

And many more...

Licensing Requirements for the Master Passphrase

Model

All models


Base License.






Adding or Changing the Master Passphrase

This section describes how to configure the master passphrase feature.

Prerequisites

•

If failover is enabled but no failover shared key is set, then changing the master passphrase displays an error message, informing you that a failover shared key must be entered to protect the master passphrase changes from being sent as plain text.

In the Configuration > Device Management > High Availability > Failover pane, enter any character in the Shared Key field or 32 hexdecimal numbers (0-9A-Fa-f) if failover hex key is selected except a back space

.

Then click

Apply

.

Detailed Steps

OL-20339-01

Step 1

Step 2

In single contex mode, choose

Configuration

>


>

Advanced

>

Master

Passphrase

pane.

In multiple context mode, choose

Configuration

>


>

Device Administration

>

Master Passphrase.

Check the

Advanced Encryption Standard (AES) password encryption

check box.

If no master passphrase is in effect, a warning statement appears when you click

Apply

. You can click

OK

or

Cancel

to continue.

If you later disable password encryption, all existing encrypted passwords are left unchanged, and as long as the master passphrase exists, the encrypted passwords will be decrypted as required by the application.


9-7



Step 3

Step 4

Check the

Change the encryption master passphrase

check box; this will enable you to enter and confirm your new master passphrases. By default, they are disabled.

Your new master passphrase must be between 8 and 128 characters long.

If you are changing an existing passphrase, you must enter the old passphrase before you can enter a new one.

To delete the master passphrase, just leave the New and Confirm master passphrase fields blank.

Click

Apply

.

You will see warning messages if:

•

•

The


field is enabled, and the new master passphrase field is empty, then the

no key configuration-key password-encrypt

command will be sent to the device. A warning message appears when you click

Apply

.

The old master passphrase does not match the hash value in the

show password encryption

command output.

•

•

•

•

•

You use non-portable characters, particularly those with the high-order bit set in an 8-bit representation.

A master passphrase and failover are in effect, then an attempt to remove the failover shared key displays an error message.

Eencryption is disabled, but a new or replacement master passphrase is supplied.You can click

OK

or

Cancel

to continue.

If the master passphrase is changed, in multiple security context mode.

•

If Active/Active failover is configured and the master passphrase is changed.

If any running configurations are configured so that their configuration cannot be saved back to their server, such as with context config-URLs that use HTTP or HTTPS and the master passphrase is changed.

Disabling the Master Passphrase

Disabling the master passphrase reverts encrypted passwords into plain text passwords. Removing the passphrase might be useful if you downgrade to a previous software version that does not support encrypted passwords.

Prerequisites

•

You must know the current master passphrase to disable it. If you do not know the passphrase, see the

“Recovering the Master Passphrase” section on page 9-9

.

•

9-8


OL-20339-01



Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

In single contex mode, choose

Configuration

>


>

Advanced

>

Master

Passphrase

pane.

In multiple context mode, choose

Configuration

>


>

Device Administration

>

Master Passphrase.

Check the

Advanced Encryption Standard (AES) password encryption

check box.

If no master passphrase is in effect, a warning statement appears when you click

Apply

. You can click

OK

or

Cancel

to continue.

Check the


check box.

Enter your old master passphrase in the Old master passphrase field. You must provide your old master passphrase to disable your passphrase.

Leave the New master passphrase and the Confirm master passphrase fields empty.

Click

Apply

.

Recovering the Master Passphrase

You cannot recover the master passphrase.

If the master passphrase is lost or unknown, it could be removed by using the

write erase

command followed by the

reload

command. This removes the master key along with the configuration containing the encrypted passwords.

Feature History for the Master Passphrase

Table 1

Table 9-2


Feature History for the Master Passphrase

Feature Name

Master Passphrase

Platform

Releases

8.3(1)




Configuration

>


>

Advanced

>

Master Passphrase

,

Configuration

>


>

Device

Administration

>

Master Passphrase

.

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9-9


Configuring the DNS Server

Configuring the DNS Server

Some adaptive security appliance features require use of a DNS server to access external servers by domain name; for example, the Botnet Traffic Filter feature requires a DNS server to access the dynamic database server and to resolve entries in the static database. Other features, such as the

ping

or

traceroute

command, let you enter a name that you want to PING for traceroute, and the adaptive security appliance can resolve the name by communicating with a DNS server. Many SSL VPN and certificate commands also support names.

Prerequisites

Note

The adaptive security appliance has limited support for using the DNS server, depending on the feature.

For these feature, to resolve the server name to an IP address you must enter the IP address manually by adding the server name in the Configuration > Firewall > Objects > Network Object/Groups pane.

For information about dynamic DNS, see the

“Configuring Dynamic DNS” section on page 11-2 .

Make sure you configure the appropriate routing for any interface on which you enable DNS domain lookup so you can reach the DNS server. See the

“Information About Routing” section on page 18-1

for more information about routing.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

In the ASDM main application window, choose

Configuration > Device Management > DNS > DNS

Client

.

In the DNS Setup area, choose one of the following options:

•

•

Configure one DNS server group.

Configure multiple DNS server groups.

Click

Add

to display the Add DNS Server Group dialog box.

Specify up to six addresses to which DNS requests can be forwarded. The adaptive security appliance tries each DNS server in order until it receives a response.

Note

You must first enable DNS on at least one interface before you can add a DNS server. The DNS

Lookup area shows the DNS status of an interface. A False setting indicates that DNS is disabled. A True setting indicates that DNS is enabled.

Step 5

Step 6

Step 7

Step 8

Step 9

Enter the name of each configured DNS server group.

Enter the IP addresses of the configured servers, and click

Add

to include them in the server group. To remove a configured server from the group, click

Delete

.

To change the sequence of the configured servers, click

Move Up

or

Move Down

.

In the Other Settings area, enter the number of seconds to wait before trying the next DNS server in the list, between 1 and 30 seconds. The default is 2 seconds. Each time the adaptive security appliance retries the list of servers, the timeout time doubles.

Enter the number of seconds to wait before trying the next DNS server in the group.

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Defining ASDM Preferences

Step 10

Step 11

Step 12

Step 13

Step 14

Step 15

Step 16

Enter a valid DNS domain name for the group of configured servers (for example, example.com).

Click

OK

to close the Add DNS Server Group dialog box.

The new DNS server settings appear.

To change these settings, click

Edit

to display the Edit DNS Server Group dialog box.

Make your desired changes, then click

OK

to close the Edit DNS Server Group dialog box.

The revised DNS server settings appear.

To enable a DNS server group to receive DNS requests, click

Set Active

.

In the DNS Guard area, to enforce one DNS response per query, check the

Enable DNS Guard on all interfaces

check box. If DNS inspection is enabled, this setting is ignored on the selected interface.

Click

Apply

to save your changes, or click

Reset

to discard those changes and enter new ones.


This feature lets you define the behavior of certain ASDM settings.

To change various settings in ASDM, perform the following steps:

Step 1

Step 2

Step 3


Tools > Preferences

.

The Preferences dialog box appears, with three tabs: General, Rules Table, and Syslog.

To define your settings, click one of these tabs: the

General

tab to specify general preferences; the

Rules

Table

tab to specify preferences for the Rules table; and the

Syslog

tab to specify the appearance of syslog messages displayed in the Home pane and to enable the display of a warning message for

NetFlow-related syslog messages.

On the General tab, specify the following:

a.

b.

Check the

Warn that configuration in ASDM is out of sync with the configuration in ASA

check box to be notified when the startup configuration and the running configuration are no longer in sync with each other.

Check the

Show configuration restriction message to read-only user

check box to display the following message to a read-only user at startup. This option is checked by default.

“You are not allowed to modify the ASA configuration, because you do not have sufficient privileges.”

c.

d.

e.

f.

g.

Check the

Confirm before exiting ASDM

check box to display a prompt when you try to close

ASDM to confirm that you want to exit. This option is checked by default.

Check the

Enable screen reader support (requires ASDM restart)

check box to enable screen readers to work. You must restart ASDM to enable this option.

Check the

Preview commands before sending them to the device

check box to view CLI commands generated by ASDM.

Check the

Enable cumulative (batch) CLI delivery

check box to send multiple commands in a single group to the adaptive security appliance.

Enter the minimum amount of time in seconds for a configuration to send a timeout message. The default is 60 seconds.

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9-11



Step 4

Step 5

Step 6 h.

To allow the Packet Capture Wizard to display captured packets, enter the name of the network sniffer application or click

Browse

to find it in the file system.

On the Rules Table tab, specify the following:

a.

Display settings let you change the way rules appear in the Rules table.

–

–

Check the

Auto-expand network and service object groups with specified prefix

check box to display the network and service object groups automatically expanded based on the

Auto-Expand Prefix setting.

In the Auto-Expand Prefix field, enter the prefix of the network and service object groups to expand automatically when displayed.

b.

–

–

Check the

Show members of network and service object groups

check box to display members of network and service object groups and the group name in the Rules table. If the check box is not checked, only the group name is displayed.

In the Limit Members To field, enter the number of network and service object groups to display. When the object group members are displayed, then only the first

n

members are displayed.

–

Check the

Show all actions for service policy rules

check box to display all actions in the

Rules table. When unchecked, a summary appears.

Deployment settings let you configure the behavior of the adaptive security appliance when deploying changes to the Rules table.

c.

–

Check the

Issue “clear xlate” command when deploying access lists

check box to clear the

NAT table when deploying new access lists. This setting ensures the access lists that are configured on the adaptive security appliance are applied to all translated addresses.

Access Rule Hit Count Settings let you configure the frequency for which the hit counts are updated in the Access Rules table. Hit counts are applicable for explicit rules only. No hit count will be displayed for implicit rules in the Access Rules table.

–

–

Check the

Update access rule hit counts automatically

check box to have the hit counts automatically updated in the Access Rules table.

In the Update Frequency field, specify the frequency in seconds in which the hit count column is updated in the Access Rules table. Valid values are 10 - 86400 seconds.

On the Syslog tab, specify the following:

•

In the Syslog Colors area, you can customize the message display by configuring background or foreground colors for messages at each severity level. The Severity column lists each severity level by name and number. To change the background color or foreground color for messages at a specified severity level, click the corresponding column. The Pick a Color dialog box appears. Click one of the following tabs:

–

–

On the Swatches tab, choose a color from the palette, and click

OK

.

On the HSB tab, specify the H, S, and B settings, and click

OK

.

•

–

On the RGB tab, specify the Red, Green, and Blue settings, and click

OK

.

In the NetFlow area, to enable the display of a warning message to disable redundant syslog messages, check the

Warn to disable redundant syslog messages when NetFlow action is first applied to the global service policy rule

check box.

After you have specified settings on these three tabs, click

OK

to save your settings and close the

Preferences dialog box.

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Using the ASDM Assistant

Note

Each time that you check or uncheck a preferences setting, the change is saved to the .conf file and becomes available to all the other ASDM sessions running on the workstation at the time. You must restart ASDM for all changes to take effect.

Using the ASDM Assistant

The ASDM Assistant tool lets you search and view useful ASDM procedural help about certain tasks.

To access information, choose

View > ASDM Assistant > How Do I?

or enter a search request from the

Look For field in the menu bar. From the Find drop-down list, choose

How Do I?

to begin the search.

Note

This feature is not available on the PIX security appliance.

To view the ASDM Assistant, perform the following steps:

Step 1

Step 2

Step 3


View > ASDM Assistant

.

The ASDM Assistant pane appears.

In the Search field, enter the information that you want to find, and click

Go

.

The requested information appears in the Search Results pane.

Click any links that appear in the Search Results and Features sections to obtain more details.

Enabling History Metrics

The Configuration > Device Management > Advanced > History Metrics pane lets you configure the adaptive adaptive security appliance to keep a history of various statistics, which ASDM can display on any Graph/Table. If you do not enable history metrics, you can only monitor statistics in real time.

Enabling history metrics lets you view statistics graphs from the last 10 minutes, 60 minutes, 12 hours, and 5 days.

To configure history metrics, perform the following steps:

Step 1

Step 2

Choose

Configuration > Device Management > Advanced > History Metrics

.

The History Metrics pane appears.

Check the

ASDM History Metrics

check box to enable history metrics, and then click

Apply

.

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9-13


Setting the Management IP Address for a Transparent Firewall


This section describes how to configure the management IP address for transparent firewall mode, and includes the following topics:

•

Information About the Management IP Address, page 9-14

•

•

•

•

•

Licensing Requirements for the Management IP Address for a Transparent Firewall, page 9-14


Configuring the IPv4 Address, page 9-15

Configuring the IPv6 Address, page 9-16

Feature History for the Management IP Address for a Transparent Firewall, page 9-18

Information About the Management IP Address

A transparent firewall does not participate in IP routing. The only IP configuration required for the adaptive security appliance is to set the management IP address. This address is required because the adaptive security appliance uses this address as the source address for traffic originating on the adaptive security appliance, such as system messages or communications with AAA servers. You can also use this address for remote management access.

For IPv4 traffic, the management IP address is required to pass any traffic. For IPv6 traffic, you must, at a minimum, configure the link-local addresses to pass traffic, but a global management address is recommended for full functionality, including remote management and other management operations.

Note

In addition to the management IP address for the device, you can configure an IP address for the

Management 0/0 or 0/1 management-only interface. This IP address can be on a separate subnet from the main management IP address. See the


Although you do not configure IPv4 or global IPv6 addresses for other interfaces, you still need to

configure the security level and interface name according to the “Configuring General Interface

Parameters” section on page 8-22

.

Licensing Requirements for the Management IP Address for a Transparent

Firewall

Model

All models


Base License.



9-14


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Supported in single and multiple context mode. For multiple context mode, set the management IP address within each context.


Supported in transparent firewall mode. For routed mode, set the IP address for each interface according to the

“Configuring General Interface Parameters” section on page 8-22

.

IPv6 Guidelines

•

Supports IPv6.

•

The following IPv6 address-related commands are not supported in transparent mode, because they require router capabilities:

– ipv6 address autoconfig

•

•

– ipv6 nd suppress-ra

For a complete list of IPv6 commands that are not supported in transparent mode, see the

“IPv6-Enabled Commands” section on page 18-9

.

No support for IPv6 anycast addresses.

You can configure both IPv6 and IPv4 addresses.


•

In addition to the management IP address for the device, you can configure an IP address for the

Management 0/0 or 0/1 management-only interface. This IP address can be on a separate subnet

from the main management IP address. See the “Configuring General Interface Parameters” section on page 8-22 .

•

Although you do not configure IP addresses for other interfaces, you still need to configure the security level and interface name according to the


Configuring the IPv4 Address

This section tells how to configure the IPv4 address.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Go to Configuration > Device Management > Management Access > Management IP Address.

In the IPv4 Address area, enter the IP address in the Management IP Address field.

This address must be on the same subnet as the upstream and downstream routers. You cannot set the subnet to a host subnet (255.255.255.255). The

standby

keyword and address is used for failover.

From the Subnet Mask drop-down list, choose a subnet mask, or enter a subnet mask directly in the field.

Click

Apply

.

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9-15



Configuring the IPv6 Address

You can configure two types of unicast addresses for IPv6:

•

Global—The global address is a public address that you can use on the public network. This address needs to be configured for the whole device, and not per-interface.

•

Link-local—The link-local address is a private address that you can only use on the directly-connected network. Routers do not forward packets using link-local addresses; they are only for communication on a particular physical network segment. They can be used for address configuration or for the ND functions such as address resolution and neighbor discovery. Because the link-local address is only available on a segment, and is tied to the interface MAC address, you need to configure the link-local address per interface.

At a minimum, you need to configure a link-local addresses for IPv6 to operate. If you configure a global address, a link-local addresses is automatically configured on each interface, so you do not also need to specifically configure a link-local address. If you do not configure a global address, then you need to configure the link-local address, either automatically or manually.

See the

“IPv6 Addresses” section on page A-5

for more information about IPv6 addressing.

This section describes how to configure the global address or the link-local address, and includes the following topics:

•

•

•

Configuring the Link-Local Addresses Automatically, page 9-17

Configuring the Link-Local Addresses Automatically, page 9-17

Configuring DAD Settings, page 9-17

Configuring the Global Address

To set the management IPv6 address, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7


In the IPv6 Addresses area, click

Add

.

The Add IPv6 Management Address dialog box appears.

In the IP Address field, enter an IPv6 address.

For example, 2001:0DB8::BA98:0:3210. See the

“IPv6 Addresses” section on page A-5 for more

information about IPv6 addressing.

In the Prefix Length field, enter the prefix length.

For example, 48. See the

“IPv6 Addresses” section on page A-5

for more information about IPv6 addressing.

Click

OK

.

To configure additional addresses, repeat

Step 2 through Step 5

.

Click

Apply

.

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Configuring the Link-Local Addresses Automatically

If you only need to configure a link-local address and are not going to assign any other IPv6 addresses, you have the option of generating the link-local addresses based on the interface MAC addresses

(Modified EUI-64 format). To manually assign the link-local address, see the

“Configuring the

Link-Local Address on an Interface (Transparent Firewall Mode)” section on page 8-30 .

To automatically configure the link-local addresses for all interfaces, perform the following steps:

Step 1

Step 2


In the IPv6 configuration area, check

Enable IPv6

.

This option enables IPv6 on all interfaces and automatically generates the link-local addresses using the

Modified EUI-64 interface ID based on the interface MAC address.

Note

You do not need to check this option if you configure any IPv6 addresses (either global or link-local); IPv6 support is automatically enabled as soon as you assign an IPv6 address.

Similarly, unchecking this option does not disable IPv6 if you configured IPv6 addresses.

Step 3

To configure IPv6 DAD parameters, shown in this area, see the

“Configuring DAD Settings” section on page 9-17

.

Click

Apply

.


DAD verifies the uniqueness of new unicast IPv6 addresses before they are assigned and ensures that duplicate IPv6 addresses are detected in the network on a link basis.

For information about the Enable IPv6 parameter, see the “Configuring the Link-Local Addresses

Automatically” section on page 9-17

.

To specify DAD settings on an interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4


In the IPv6 configuration area, in the DAD attempts field, enter the number of allowed DAD attempts.

This setting configures the number of consecutive neighbor solicitation messages that are sent on an interface while DAD is performed on IPv6 addresses. Valid values are from 0 to 600. A zero value disables DAD processing on the specified interface. The default is one message.

In the NS Interval field, enter the neighbor solicitation message interval.

The neighbor solicitation message requests the link-layer address of a target node. Valid values are from

1000 to 3600000 milliseconds. The default is 1000 milliseconds.

In the Reachable Time field, enter the amount of time in seconds that a remote IPv6 node is considered reachable after a leachability confirmation event has occurred.

Valid values are from 1000 to 3600000 milliseconds. The default is zero. A configured time enables the detection of unavailable neighbors. Shorter times enable detection more quickly; however, very short configured times are not recommended in normal IPv6 operation.

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9-17



Step 5

Click

Apply

.

Feature History for the Management IP Address for a Transparent Firewall

Table 9-2


Feature History for Transparent Mode Management Address

Feature Name

IPv6 support

Releases

8.2(1)


IPv6 support was introduced for transparent firewall mode.

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C H A P T E R

10

Configuring DHCP

This chapter describes how to configure the DHCP server, and includes the following topics:

•

Information About DHCP, page 10-1

•

•

•

•

•

•

Licensing Requirements for DHCP, page 10-1


Configuring DHCP Relay Services, page 10-2

Configuring a DHCP Server, page 10-5

DHCP Monitoring, page 10-8

Feature History for DHCP, page 10-9

Information About DHCP

DHCP provides network configuration parameters, such as IP addresses, to DHCP clients. The adaptive security appliance can provide a DHCP server or DHCP relay services to DHCP clients attached to adaptive security appliance interfaces. The DHCP server provides network configuration parameters directly to DHCP clients. DHCP relay passes DHCP requests received on one interface to an external

DHCP server located behind a different interface.

Licensing Requirements for DHCP

Table 10-1

shows the licensing requirements for DHCP.

Table 10-1 Licensing Requirements

Model

All models


Base License.

For the Cisco ASA 5505 adaptive security appliance, the maximum number of DHCP client addresses varies depending on the license:

•

If the limit is 10 hosts, the maximum available DHCP pool is 32 addresses.

•

If the limit is 50 hosts, the maximum available DHCP pool is 128 addresses.

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10-1

Chapter 10 Configuring DHCP


•

If the number of hosts is unlimited, the maximum available DHCP pool is 256 addresses.

Note

By default, the Cisco ASA 5505 adaptive security appliance ships with a 10-user license.


Use the following guidelines to configure the DHCP server:

•

•

•

You can configure a DHCP server on each interface of the adaptive security appliance. Each interface can have its own pool of addresses to draw from. However the other DHCP settings, such as DNS servers, domain name, options, ping timeout, and WINS servers, are configured globally and used by the DHCP server on all interfaces.

You cannot configure a DHCP client or DHCP relay services on an interface on which the server is enabled. Additionally, DHCP clients must be directly connected to the interface on which the server is enabled.

The adaptive security appliance does not support QIP DHCP servers for use with DHCP proxy.

•

•

When it receives a DHCP request, the adaptive security appliance sends a discovery message to the

DHCP server. This message includes the IP address (within a subnetwork) configured with the

dhcp-network-scope

command in the group policy. If the server has an address pool that falls within that subnetwork, the server sends the offer message with the pool information to the IP address—not to the source IP address of the discovery message.

For example, if the server has a pool in the range of 209.165.200.225 to 209.165.200.254, mask

255.255.255.0, and the IP address specified by the

dhcp-network-scope

command is

209.165.200.1, the server sends that pool in the offer message to the adaptive security appliance.


Supports Active/Active and Active/Standby failover.


Supported in routed and transparent firewall modes.


Supported in single mode and multiple context mode.

•

Configuring DHCP Relay Services

The DHCP Relay pane lets you configure DHCP relay services on the adaptive security appliance.

DHCP relay passes DHCP requests received on one interface to an external DHCP server located behind a different interface. To configure DHCP relay, you must specify at least one DHCP relay global server and then enable a DHCP relay agent on the interface that receives DHCP requests.


•

•

Editing DHCP Relay Agent Settings, page 10-4

Adding or Editing Global DHCP Relay Server Settings, page 10-4

10-2


OL-20339-01



Restrictions

•

You cannot enable a DHCP relay agent on an interface that has a DHCP relay global server configured for it. You must disable the DHCP server before you can enable a DHCP relay agent.

•

The DHCP relay agent works only with external DHCP servers; it does not forward DHCP requests to an adaptive security appliance interface configured as a DHCP server.

Prerequisites

Before you can enable a DHCP relay agent on an interface, you must have at least one global DHCP relay server configured or one DHCP relay interface server configured.

To configure DHCP relay services, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10


Configuration > Device Management > DHCP >

DHCP Relay

.

To configure a new external server to which DHCP requests may be relayed, click

Add

to display the

Add Global DHCP Relay Server dialog box. You can define up to four global DHCP relay servers. on the adaptive security appliance. If you already have defined four DHCP relay global servers, the Add button is dimmed.

Enter the IP address of the DHCP server, or click the ellipses to display the Browse DHCP Server dialog box.

Double-click a DHCP server from the list to add it to the DHCP Server field, and then click

OK

to close the Browse DHCP Server dialog box.

The newly selected DHCP server appears in the DHCP Server field.

Choose the interface to which the specified DHCP server is attached from the drop-down list, then click

OK to close the Add Global DHCP Relay Server dialog box.

The newly added global DHCP relay server appears in the Global DHCP Relay Servers list.

Enter the amount of time, in seconds, allowed for DHCP address negotiation. Valid values range from 1 to 3600 seconds. The default value is 60 seconds.

To change a selected DHCP relay server settings, click

Edit

to display the Edit Global DHCP Relay

Server dialog box.

Make your desired changes, and then click

OK

to close the Edit Global DHCP Relay Server dialog box.

To remove a selected DHCP relay server from the list, click

Delete

.

The DHCP Relay Agent area is display-only, and shows the following information:

•

•

The configured interfaces.

The DHCP Relay Enabled column, which indicates whether the selected DHCP relay agent is enabled on the interface. The check box is checked if the DHCP relay agent is enabled, and is unchecked if the DHCP relay agent is not enabled on the interface.

•

The Set Route column, which indicates whether the selected DHCP relay agent is configured to modify the default router address in the information returned from the DHCP server. The check box is checked if the DHCP relay agent is configured to change the default router address to the interface address, and is unchecked if the DHCP relay agent does not modify the default router address.

To change DHCP Relay Agent Settings, see the “Editing DHCP Relay Agent Settings” section on page 10-4

.

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10-3



Editing DHCP Relay Agent Settings

You can enable the DHCP relay agent and configure the relay agent parameters for the selected interface.

Restrictions

•

You cannot enable a DHCP relay agent on an interface that has a global DHCP relay server configured for it.

•

You cannot enable a DHCP relay agent on an adaptive security appliance that has a DHCP server configured on an interface.

Prerequisites

Before you can enable a DHCP relay agent on an selected interface, you must have at least one global

DHCP relay server in the configuration.

To modify DHCP Relay Agent Settings, perform the following steps:

Step 1

Step 2

Step 3

To enable the DHCP relay agent on the selected interface, check the

Enable DHCP Relay Agent

check box. You must have a global DHCP relay server defined before enabling the DHCP relay agent.

To specify whether the DHCP relay agent is configured to modify the default router address in the information returned from the DHCP server, check the

Set Route

check box. The DHCP relay agent then substitutes the address of the selected interface for the default router address in the information returned from the DHCP server.

To add or edit global DHCP relay server settings, see the

“Configuring DHCP Relay Services” section on page 10-2

.

Adding or Editing Global DHCP Relay Server Settings

You can define new global DHCP relay servers or edit existing server information. You can define up to four global DHCP relay servers.

Restrictions

You cannot define a global DHCP relay server on an interface that has an enabled DHCP server.

To add a global DHCP relay server to which DHCP requests will be relayed, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

In the Global DHCP Relay Servers area, click

Add

to display the Add Global Relay Servers dialog box.

In the DHCP Server field, enter the IP address of the external DHCP server to which DHCP requests are forwarded, or click the ellipses to display the Browse DHCP Server dialog box.

To continue, see

Step 4

of

“Configuring a DHCP Server” section on page 10-5

.

Choose the interface through which DHCP requests are forwarded to the external DHCP server from the drop-down list.

Click

OK

to close the Add Global Relay Servers dialog box. The newly added global DHCP relay server appears in the list.

To modify global DHCP relay server settings, click

Edit

to display the Edit DHCP Global Relay Servers dialog box.

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Configuring a DHCP Server

Step 7

Step 8

Make the desired changes, and then click

OK

to close the Edit DHCP Global Relay Servers dialog box.

The updated global DHCP relay server settings appear in the list.

Click

Apply


Reset

to discard them and enter new ones.


You can configure one DHCP server per interface on an adaptive security appliance.


•

•

Editing DHCP Servers, page 10-6

Configuring Advanced DHCP Options, page 10-7

Note

You cannot configure a DHCP server on an interface that has a DHCP relay configured on it. For more information, see the

“Configuring DHCP Relay Services” section on page 10-2

.

To configure an ASA interface as a DHCP Server, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

In the Global DHCP Options area, check the

Enable Auto-configuration from interface

check box to enable DHCP auto configuration and choose the interface from the drop-down list.

DHCP auto configuration enables the DHCP Server to provide DHCP clients with DNS server, domain name, and WINS server information obtained from a DHCP client running on the specified interface. If information obtained through auto configuration is also specified manually in the Global DHCP Options area, the manually specified information takes precedence over the discovered information.

To override the interface DHCP or PPPoE client WINS parameter with the VPN client parameter, check the

Allow VPN override

check box.

In the DNS Server 1 field, enter the IP address of the primary DNS server for a DHCP client.

In the DNS Server 2 field, enter the IP address of the alternate DNS server for a DHCP client.

In the Domain Name field, enter the DNS domain name for DHCP clients (for example, example.com).

In the Lease Length field, enter the amount of time, in seconds, that the client can use its allocated IP address before the lease expires. Valid values range from 300 to 1048575 seconds. The default value is

3600 seconds (1 hour).

In the Primary WINS Server field, enter the IP address of the primary WINS server for a DHCP client.

In the Secondary WINS Server field, enter the IP address of the alternate WINS server for a DHCP client.

To avoid address conflicts, the adaptive security appliance sends two ICMP ping packets to an address before assigning that address to a DHCP client. In the Ping Timeout field, enter the amount of time, in milliseconds, that the adaptive security appliance waits to time out a DHCP ping attempt. Valid values range from 10 to 10000 milliseconds. The default value is 50 milliseconds.

To specify additional DHCP options and their parameters, click

Advanced

to display the

Configuring

Advanced DHCP Options dialog box. For more information, see the “Configuring Advanced DHCP

Options” section on page 10-7

.

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10-5



Step 11

Step 12

Step 13

In the Dynamic DNS Settings for DHCP Server area, you configure the DDNS update settings for the

DHCP server. Check the

Update DNS Clients

check box to specify that, in addition to the default action of updating the client PTR resource records, the selected DHCP server should also perform the following update actions:

•

•

Check the

Update Both Records

check box to specify that the DHCP server should update both the

A and PTR RRs.

Check the

Override Client Settings

check box to specify that the DHCP server actions should override any update actions requested by the DHCP client.

To modify DHCP Server settings, click

Edit

to display the Edit DHCP Server dialog box. Alternatively, you may double-click in the row for a particular interface to open the Edit DHCP Server dialog box for

that interface. For more information, see the “Editing DHCP Servers” section on page 10-6

.

Click

Apply


Reset


Editing DHCP Servers

To enable DHCP, specify the DHCP address pool, and modify other DHCP server parameters for the selected interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

The selected interface ID appears as

display-only

. To enable the DHCP server on the selected interface, check the

Enable DHCP Server

check box. To disable DHCP on the selected interface, uncheck this check box. Disabling the DHCP server on the selected interface does not clear the specified DHCP address pool.

In the DHCP Address Pool field, enter the range of IP addresses from lowest to highest that is used by the DHCP server. The range of IP addresses must be on the same subnet as the selected interface and cannot include the IP address of the interface itself.

In the Dynamic DNS Settings for DHCP Server area, you configure the DDNS update settings for the

DHCP server.

Check the

Update DNS Clients

check box to specify that, in addition to the default action of updating the client PTR resource records, the selected DHCP server should also perform the following update actions:

•

•

To specify that the DHCP server should update both the A and PTR RRs, check the

Update Both

Records

check box.

To specify that DHCP server actions should override any update actions requested by the DHCP client, check the

Override Client Settings

check box

To enable DHCP on the interface, check the

Enable DHCP Server

check box. The DHCP Enabled column displays “Yes” if DHCP is enabled, or “No” if DHCP is disabled on the interface.

In the DNS Address Pool field, enter the revised range of IP addresses that have been assigned to the

DHCP address pool.

In the Optional Parameters area, modify the following settings:

a.

The DNS servers (1 and 2) configured for the interface.

b.

c.

The WINS servers (primary and secondary) configured for the interface.

The domain name of the interface.

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Step 7

Step 8

Step 9 d.

e.

f.

The time in milliseconds that the adaptive security appliance will wait for an ICMP ping response on the interface.

The duration of time that the DHPC server configured on the interface allows DHCP clients to use an assigned IP address.

The interface on a DHCP client that provides DNS, WINS, and domain name information for automatic configuration.

To configure more DHCP options, click

Advanced

to display the Advanced DHCP Options dialog box.


“Configuring Advanced DHCP Options” section on page 10-7 .

Click

OK

to close the Edit DHCP Server dialog box.

Click

Apply


Reset


Configuring Advanced DHCP Options

You can use advanced DHCP options to provide DNS, WINS, and domain name parameters to DHCP clients. You can also use the DHCP automatic configuration setting to obtain these values or define them manually. When you use more than one method to define this information, it is passed to DHCP clients in the following sequence:

1.

2.

Manually configured settings.

Advanced DHCP options settings.

3.

DHCP automatic configuration settings.

For example, you can manually define the domain name that you want the DHCP clients to receive, and then enable DHCP automatic configuration. Although DHCP automatic configuration discovers the domain together with the DNS and WINS servers, the manually-defined domain name is passed to DHCP clients with the discovered DNS and WINS server names, because the domain name discovered by the

DHCP automatic configuration process is superseded by the manually-defined domain name.

To configure advanced DHCP options, perform the following steps:

Step 1

In the Option to be Added area, define the following settings:

a.

Choose the option code from the drop-down list. All DHCP options (options 1 through 255) are supported except 1, 12, 50–54, 58–59, 61, 67, and 82.

b.

c.

Choose the options that you want to configure. Some options are standard. For standard options, the option name is shown in parentheses after the option number and the option parameters are limited to those supported by the option. For all other options, only the option number is shown and you must choose the appropriate parameters to supply with the option. For example, if you choose DHCP

Option 2 (Time Offset), you can only supply a hexadecimal value for the option. For all other DHCP options, all of the option value types are available and you must choose the appropriate options value type.

In the Option Data area, specify the type of information that the option returns to the DHCP client.

For standard DHCP options, only the supported option value type is available. For all other DHCP options, all of the option value types are available. Click

Add

to add the option to the DHCP option list. Click

Delete

to remove the option from the DHCP option list.

–

Click

IP Address

to indicate that an IP address is returned to the DHCP client. You can specify up to two IP addresses. IP Address 1 and IP Address 2 indicate an IP address in dotted-decimal notation.


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DHCP Monitoring

Note

The name of the associated IP Address fields can change based on the DHCP option that you chose. For example, if you choose DHCP Option 3 (Router), the fields names change to

Router 1 and Router 2.

–

Click

ASCII

to specify that an ASCII value is returned to the DHCP client. In the Data field, enter an ASCII character string. The string cannot include white spaces.

Note

The name of the associated Data field can change based on the DHCP option that you chose.

For example, if you choose DHCP Option 14 (Merit Dump File), the associated Data field names change to File Name.

–

Click

Hex

to specify that a hexadecimal value is returned to the DHCP client. In the Data field, enter a hexadecimal string with an even number of digits and no spaces. You do not need to use a 0x prefix.

Note

The name of the associated Data field can change based on the DHCP option you chose. For example, if you choose DHCP Option 2 (Time Offset), the associated Data field becomes the

Offset field.

Step 2

Step 3

Click OK to close the Advanced DHCP Options dialog box.

Click

Apply


Reset


DHCP Monitoring

To monitor DHCP, perform the following steps:

Path


Type

show running-config dhcpd

, then click

Send

.


Purpose

Shows the current DHCP configuration.

Shows the current DHCP relay services status.

Type

show running-config dhcprelay

, then click

Send

.

Monitoring > Interfaces > DHCP > DHCP Client Lease

Information

Shows configured DHCP Client IP addresses.

Monitoring > Interfaces > DHCP > DHCP Server Table

Shows configured dynamic DHCP Client IP addreses.

Monitoring > Interfaces > DHCP > DHCP Statistics

Shows DHCP message types, counters, values, directions, messages received, and messages sent.

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Feature History for DHCP


Table 10-2


ASDM is backwards-compatible with multiple platform releases, so the specific ASDM release in which support was added is not listed.

Table 10-2

Feature Name

DHCP

Feature History for DHCP

Releases

7.0(1)

Description



Configuration > Device Management > DHCP > DHCP Relay

Configuration > Device Management > DHCP > DHCP Server

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10-9



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C H A P T E R

11

This chapter describes how to configure DDNS update methods, and includes the following topics:

•

Information about DDNS, page 11-1

•

•

•

•

•

Licensing Requirements for DDNS, page 11-1


Configuring Dynamic DNS, page 11-2

DDNS Monitoring, page 11-4

Feature History for DDNS, page 11-4

Information about DDNS

DDNS update integrates DNS with DHCP. The two protocols are complementary: DHCP centralizes and automates IP address allocation; DDNS update automatically records the association between assigned addresses and hostnames at pre-defined intervals. DDNS allows frequently changing address-hostname associations to be updated frequently. Mobile hosts, for example, can then move freely on a network without user or administrator intervention. DDNS provides the necessary dynamic update and synchronization of the name-to-address mapping and address-to-name mapping on the DNS server. To

configure the DNS server for other uses, see the “Configuring the DNS Server” section on page 9-10

. To configure DHCP, see the

“Configuring a DHCP Server” section on page 10-5 .

Licensing Requirements for DDNS

Table 11-1

shows the licensing requirements for DDNS.


Model

All models


Base License.


11-1 OL-20339-01

Chapter 11 Configuring Dynamic DNS






Supported in routed firewall mode.


Supported in single and multiple context modes.

Supported in transparent mode for the DNS Client pane.

IPv6 Guidelines

Supports IPv6.


Dynamic DNS provides address and domain name mapping so that hosts can find each other, even though their DHCP-assigned IP addresses change frequently. The DDNS name and address mapping are stored on the DHCP server in two resource records: the A RR includes the name-to-IP address mapping, while the PTR RR maps addresses to names. Of the two methods for performing DDNS updates—the

IETF standard defined by RFC 2136 and a generic HTTP method—the adaptive security appliance supports the IETF method in this release.

The Dynamic DNS pane shows the configured DDNS update methods and the interfaces that have been configured for DDNS. By automatically recording the association between assigned addresses and hostnames at pre-defined intervals, DDNS allows frequently changing address-hostname associations to be updated regularly. Mobile hosts, for example, can then move freely on a network without user or administrator intervention.

To configure dynamic DNS client settings for updating the DNS server, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5


Configuration > Device Management > DNS >

Dynamic DNS

.

Click

Add

to display the Add Dynamic DNS Update Method dialog box.

Enter the name for the DDNS update method.

Specify the update interval between DNS update attempts configured for the update method in days, hours, minutes, and seconds.

•

Choose the number of days between update attempts from 0 to 364.

•

•

Choose the number of hours (in whole numbers) between update attempts from 0 to 23.

Choose the number of minutes (in whole numbers) between update attempts from 0 to 59.

•

Choose the number of seconds (in whole numbers) between update attempts from 0 to 59.

These units are additive. That is, if you enter 0 days, 0 hours, 5 minutes and 15 seconds, the update method tries an update every 5 minutes and 15 seconds for as long as the method is active.

To store server resource record updates that the DNS client updates, choose one of the following options:

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Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Step 12

Step 13

Step 14

•

Both the A resource record and the PTR resource record.

•

The A resource records only.

Click

OK

to close the Add Dynamic DNS Update Method dialog box.

The new dynamic DNS client settings appear.


Edit

to display the Edit Dynamic DDNS Update Method dialog box.

When you edit an existing method, the Name field is

display-only

and shows the name of the selected method for editing

Make your desired changes, and then click OK to close the Edit Dynamic DDNS Update Method dialog box.

The revised dynamic DNS client settings appear.

To remove configured settings, choose the settings from the list, and then click

Delete

.

To add DDNS settings for each interface configured for DDNS, click

Add

to display the Add Dynamic

DNS Interface Settings dialog box.

Choose the interface from the drop-down list.

Choose the update method assigned to the interface from the drop-down list.

Enter the hostname of the DDNS client.

To store resource record updates, choose one of the following options:

•

•

Default (PTR Records) to specify that the client request PTR record updating by the server.

Both (PTR Records and A Records) to specify that the client request both the A and PTR DNS resource records by the server.

•

None to specify that the client request no updates by the server.

Note

DHCP must be enabled on the selected interface for this action to take effect.

Step 15

Step 16

Step 17

Step 18

Step 19

Click

OK

to close the Add Dynamic DNS Interface Settings dialog box.

The new dynamic DNS interface settings appear.


Edit

to display the Edit Dynamic DNS Interface Settings dialog box.

Make your desired changes, and then click OK to close the Edit Dynamic DNS Interface Settings dialog box.

The revised dynamic DNS interface settings appear.

To remove configured settings, choose the settings from the list, and then click

Delete

.

Click

Apply


Reset


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11-3


DDNS Monitoring

DDNS Monitoring

To monitor DDNS, perform the following steps:

Path


Type

showrunning-config ddns

, then click

Send

.


Type

show running-config dns server-group

, then click

Send

.

Purpose

Shows the current DDNS configuration.

Shows the current DNS server group status.

Feature History for DDNS



Table 11-2

Feature Name

DDNS

Feature History for DDNS

Releases

7.0(1)




Configuration > Device Management> DNS > DNS Client

Configuration > Device Management > DNS > Dynamic DNS

.

11-4


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C H A P T E R

12

Configuring Web Cache Services Using WCCP

This chapter describes how to configure web caching services using WCCP, and includes the following sections:

•

Information About WCCP, page 12-1

•

•

•

•

•

•


Licensing Requirements for WCCP, page 12-2

Adding or Editing WCCP Service Groups, page 12-3

Configuring Packet Redirection, page 12-4

WCCP Monitoring, page 12-4

Feature History for WCCP, page 12-5

Information About WCCP

The purpose of web caching is to reduce latency and network traffic. Previously-accessed web pages are stored in a cache buffer, so if users need the page again, they can retrieve it from the cache instead of the web server.

WCCP specifies interactions between the adaptive security appliance and external web caches. The feature transparently redirects selected types of traffic to a group of web cache engines to optimize resource usage and lower response times. The adaptive security appliance only supports WCCP Version

2.

Using an adaptive security appliance as an intermediary eliminates the need for a separate router to do the WCCP redirection, because the adaptive security appliance redirects requests to cache engines.

When the adaptive security appliance determines that a packet needs redirection, it skips TCP state tracking, TCP sequence number randomization, and NAT on these traffic flows.


The following WCCPv2 features are supported for the adaptive security appliance:

•

•

•

Redirection of multiple TCP and UDP port-destined traffic.

Authentication for cache engines in a service group.

Multiple Cache Engines in a service group.

OL-20339-01


12-1

Chapter 12 Configuring Web Cache Services Using WCCP

Licensing Requirements for WCCP

•

The following WCCPv2 features are not supported for the adaptive security appliance:

•

Multiple routers in a service group.

•

•

•

GRE encapsulation.

Multicast WCCP.

The Layer 2 redirect method.

WCCP source address spoofing.

WCCP Interaction With Other Features

In the adaptive security appliance implementation of WCCP, the protocol interacts with other configurable features according to the following:

•

Cut-through proxy will not work in combination with WCCP.

•

•

•

•

An ingress access list entry always takes higher priority over WCCP. For example, if an access list does not permit a client to communicate with a server, then traffic is not redirected to a cache engine.

Both ingress interface access lists and egress interface access lists are applied.

TCP intercept, authorization, URL filtering, inspect engines, and IPS features are not applied to a redirected flow of traffic.

When a cache engine cannot service a request and a packet is returned, or when a cache miss happens on a cache engine and it requests data from a web server, then the contents of the traffic flow is subject to all the other configured features of the adaptive security appliance.

If you have two WCCP services and they use two different redirection ACLs that overlap and match the same packets (with a deny or a permit action), the packets behave according to the first service-group found and installed rules. The packets are not passed thorugh all service-groups.


Supports Active/Active and Active/Standby failover. WCCP redirect tables are not replicated to standby units. After a failover, packets are not redirected until the tables are rebuilt. Sessions redirected before failover are probably reset by the web server.





IPv6 Guidelines

Supports IPv6.

Licensing Requirements for WCCP

Table 12-1 shows the licensing requirements for WCCP.


12-2


OL-20339-01


Configuring WCCP Service Groups

Model

All models


Base License.

Configuring WCCP Service Groups

To allocate space and enable support of the specified WCCP service group, perform the following steps:

Step 2

Step 3

Step 4

Step 5

Step 6

Step 1


Configuration > Device Management > Advanced >

WCCP > Service Groups

.

To add a new service group, click

Add

to display the Add Service Group dialog box.

To modify an existing service group, click

Edit

to display the Edit Service Group dialog box.

To remove a selected service group, click

Delete

.

To continue, see

“Adding or Editing WCCP Service Groups” section on page 12-3 .

Click

Apply


Reset


Adding or Editing WCCP Service Groups

To add a new service group or change the service group parameters for a configured service group, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Click either the Web Cache Service or the Dynamic Service Number radio button. The maximum number of services, including those specified with a dynamic service identifier is 256.

Enter the dynamic service identifier, which means the service definition is dictated by the cache. Valid dynamic service numbers are 0 to 254, and are used as the name of the service group.

In the Options area, perform the following steps:

a.

b.

Choose the predefined access list that controls traffic redirected to this service group.

Choose the predefined access list that determines which web caches are allowed to participate in the service group. Only extended ACLs are allowed.

c.

Enter a password up to seven characters long, which is used for MD5 authentication for messages received from the service group.

Confirm the password.

d.

e.

Click

Manage

to display the ACL Manager window, where you can create or change an ACL.

Click

OK

to close the Add or Edit Service Group dialog box.


“Configuring Packet Redirection” section on page 12-4

.

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12-3


Configuring Packet Redirection

Configuring Packet Redirection

To configure packet redirection on the ingress of an interface using WCCP, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5


Configuration > Device Management > Advanced >

WCCP > Redirection

.

To add a new WCCP packet redirection, click

Add

to display the Add WCCP Redirection dialog box.

To modify an existing WCCP packet redirection, click

Edit

to display the Edit WCCP Redirection dialog box.

To remove a selected WCCP packet redirection, click

Delete

.


“Adding or Editing Packet Redirection” section on page 12-4

.

Adding or Editing Packet Redirection

To add or change packet redirection on the ingress of an interface using WCCP, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Choose the interface on which to enable WCCP redirection from the drop-down list.

Choose the service group from the drop-down list.

Click

OK

to close the Edit WCCP Redirection dialog box.

(Optional) If you need to create a new service group, click

New

to display the Add Service Group dialog box.

(Optional) To continue, see the “Adding or Editing WCCP Service Groups” section on page 12-3 .

WCCP Monitoring

To monitor WCCP, perform the following steps:

Path


Type

show running-config wccp

, then click

Send

.


Purpose

Shows the current WCCP configuration.

Shows the current WCCP interfaces status.

Type

show running-config wccp interface

, then click

Send

.

Monitoring > Properties > WCCP > WCCP Service

Groups

Shows configured WCCP service groups.

Monitoring > Properties > WCCP > WCCP Redirection

Shows configured WCCP interface statistics.

12-4


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Feature History for WCCP

Feature History for

WCCP

Table 12-2

lists the release history for this feature. ASDM is backwards-compatible with multiple platform releases, so the specific ASDM release in which support was added is not listed.

Table 12-2 Feature History for WCCP

Feature Name

WCCP

Releases

7.2(1)




Configuration > Device Management > Advanced > WCCP > Service Groups

Configuration > Device Management > Advanced > WCCP > Redirection

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12-5

Feature History for WCCP


12-6


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C H A P T E R

13

Configuring Objects

Objects are reusable components for use in your configuration. They can be defined and used in adaptive security appliance configurations in the place of inline IP addresses. Objects make it easy to maintain your configurations because you can modify an object in one place and have it be reflected in all other places that are referencing it. Without objects you would have to modify the parameters for every feature when required, instead of just once. For example, if a network object defines an IP address and subnet mask, and you want to change the address, you only need to change it in the object definition, not in every feature that refers to that IP address.

This chapter describes how to configure objects, and it includes the following sections:

•

•

•

•

Configuring Network Objects and Groups, page 13-1

Configuring Service Objects and Service Groups, page 13-5

Configuring Regular Expressions, page 13-10

Configuring Time Ranges, page 13-15

Note

For other objects, see the following sections:

•

•

•

Class Maps—See

Chapter 36, “Getting Started With Application Layer Protocol Inspection.”

Inspect Maps—See

Chapter 36, “Getting Started With Application Layer Protocol Inspection.”

TCP Maps—See the

“Configuring Connection Settings” section on page 48-5 .

Configuring Network Objects and Groups

This section describes how to use network objects and groups, and it includes the following topics:

•

Network Object Overview, page 13-2

•

•

•

•

Configuring a Network Object, page 13-2

Configuring a Network Object Group, page 13-3

Using Network Objects and Groups in a Rule, page 13-4

Viewing the Usage of a Network Object or Group, page 13-4


13-1 OL-20339-01

Chapter 13 Configuring Objects


Network Object Overview

A network object can contain a host, a network IP address, or a range of IP addresses, and it can also enable NAT rules. (See

Chapter 27, “Configuring Network Object NAT,” for more information.)

Network objects let you predefine host and network IP addresses so that you can streamline subsequent configurations. For example, when you configure a security policy, such as an access rule or a AAA rule, you can choose these predefined addresses instead of typing them in manually. Moreover, if you change the definition of an object, the change is inherited automatically by any rules that use the altered object.

You can add network objects manually, or you can let ASDM automatically create objects from existing configurations, such as access rules and AAA rules. If you edit one of these derived objects, it persists even if you later delete the rule that used it. Otherwise, derived objects only reflect the current configuration if you refresh.

A network object group is a group that contains multiple hosts and networks together, so a network object group can also contain other network object groups. You can also specify a network object group as the source address or destination address in an access rule.

When you are configuring rules, the ASDM window includes an Addresses side pane that shows available network objects and network object groups; you can add, edit, or delete objects directly in the

Addresses pane. You can also drag additional network objects and groups from the Addresses pane to the source or destination of a selected access rule.

Also, you can create a named object within a network object group, which provides the ability to modify an object in one place and have it be reflected in all other places that are referencing it. Otherwise, modifying an object requires a manual process of changing all IP address and mask pairs in the configuration. In addition, you can attach a named object to (or detach it from) one or more object groups to ensure that objects are not duplicated but are used efficiently. The object can then be re-used and cannot be deleted if other modules are still referencing it.

Configuring a Network Object

For information about network objects, see the

“Network Object Overview” section on page 13-2 .

To add or edit a network object, perform the following steps:

Step 1

Step 2

Step 3

Choose

Configuration

>

Firewall

>

Objects

>

Network Objects/Group

.

Click

Add

, and choose

Network Object

to add a new object, or choose an existing object to edit, and click

Edit

.

You can also add or edit network objects from the Addresses side pane in a rules window or when you are adding a rule.

To find an object in the list, enter a name or IP address in the Filter field, and click

Filter

. The wildcard characters asterisk (*) and question mark (?) are allowed.

The Add/Edit Network Object dialog box appears.

Fill in the following values:

•

Name—The object name. Use characters a to z, A to Z, 0 to 9, a period, a dash, a comma, or an underscore. The name must contain 64 characters or fewer.

•

Type—Either Network, Host, or Range.

13-2


OL-20339-01



•

•

•

IP Address—An IPv4 or an IPv6 address, either a host or network address. When you enter a colon

(:) in this field for an IPv6 address, the Netmask field changes to Prefix Length. If you select Range as the object type, the IP Address field changes to allow you to enter a Start Address and an End address.

Netmask or Prefix Length—If the IP address is an IPv4 address, enter the subnet mask. If the IP address is an IPv6 address, enter the prefix. (This field is not available if you enter the object type as Host.)

Description—(Optional) The description of the network object (up to 200 characters in length).

Note

To add NAT rules to the network object, see Chapter 27, “Configuring Network Object NAT,”


Step 4

Step 5

Click

OK

.

Click

Apply


You can now use this network object when you create a rule. If you edited an object, the change is inherited automatically by any rules using the object.

Note

You cannot delete a network object that is in use.

Configuring a Network Object Group

For information about network object groups, see the

“Network Object Overview” section on page 13-2 .

To configure a network object or a network object group, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Choose

Configuration

>

Firewall

>

Objects

>

Network Objects/Groups

.

Click click

Add > Network Object Group

to add either a new object or a new object group.

You can also add or edit network object groups from the Addresses side pane in a rules window, or when you add a rule.

To find an object in the list, enter a name or IP address in the Filter field, and click Filter. The wildcard characters asterisk (*) and question mark (?) are allowed.

The Add Network Object Group dialog box appears.

In the Group Name field, enter a group name.

Use characters a to z, A to Z, 0 to 9, a period, a comma, a dash, or an underscore. The name must contain

64 characters or fewer.

(Optional) In the Description field, enter a description, up to 200 characters in length.

You can add existing objects or groups to the new group (nested groups are allowed), or you can create a new address to add to the group:

•

To add an existing network object or group to the new group, double-click the object in the Existing

Network Objects/Groups pane.

You can also select the object, and then click

Add

. The object or group is added to the right-hand

Members in Group pane.


OL-20339-01 13-3



Step 6

•

To add a new address, fill in the values under the Create New Network Object Member area, and click

Add

.

The object or group is added to the right-hand Members in Group pane. This address is also added to the network object list.

To remove an object, double-click the object in the Members in Group pane, or select the object and click

Remove

.

After you add all the member objects, click OK.

You can now use this network object group when you create a rule. For an edited object group, the change is inherited automatically by any rules using the group.

Note

You cannot delete a network object group that is in use.

Using Network Objects and Groups in a Rule

When you create a rule, you can enter an IP address manually, or you can browse for a network object or group to use in the rule. To use a network object or group in a rule, perform the following steps:

Step 1

Step 2

Step 3

From the rule dialog box, click the

...

browse button next to the source or destination address field.

The Browse Source Address or Browse Destination Address dialog box appears.

You can either add a new network object or group, or choose an existing network object or group by double-clicking it.

To find an object in the list, enter a name or IP address in the Filter field, and click

Filter

. The wildcard characters asterisk (*) and question mark (?) are allowed.

•

To add a new network object, see the

“Configuring a Network Object” section on page 13-2 .

•

To add a new network object group, see the

“Configuring a Network Object Group” section on page 13-3 .

After you add a new object or double-click an existing object, it appears in the Selected

Source/Destination field. For access rules, you can add multiple objects and groups in the field, separated by commas.

Click

OK

.

You return to the rule dialog box.

Viewing the Usage of a Network Object or Group

To view which rules use a network object or group, in the Configuration > Firewall > Objects > Network

Objects/Group pane, click the magnifying glass Find icon.

The Usages dialog box appears, listing all the rules currently using the network object or group. This dialog box also lists any network object groups that contain the object.

13-4


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Configuring Service Objects and Service Groups


This section describes how to configure service objects and service groups, and it includes the following topics:

•

Information about Service Objects and Service Groups, page 13-5

•

•

•

Adding and Editing a Service Object, page 13-6

Adding and Editing a Service Group, page 13-7

Browse Service Groups, page 13-9

Information about Service Objects and Service Groups

A service object contains a protocol and optional (source and/or destination) port and an associated description. You create and use a service object in adaptive security appliance configurations in the place of an inline IP address in a configuration. You can define an object with a particular IP address/mask pair or a protocol (and optionally a port) and use this object in several configurations.

The advantage to using an object is that whenever you want to modify the configurations related to this

IP address or protocol, you do not need to search the running configuration and modify the rules in all places. You can modify the object once, and then the change automatically applies to all rules that use this object.

Service objects can be used in NAT configurations, access lists, and object groups.

You can associate multiple services into a named service group. You can specify any type of protocol and service in one group or create service groups for each of the following types:

•

TCP ports

•

•

UDP ports

ICMP types

•

IP protocols

Multiple service groups can be nested into a “group of groups” and used as a single group.

You can use a service group for most configurations that require you to identify a port, ICMP type, or protocol. When you are configuring NAT or security policy rules, the ASDM window even includes a

Services pane at the right that shows available service groups and other global objects; you can add, edit, or delete objects directly in the Services pane.

You can also create a named object in a service object group, which provides the ability to modify an object in one place and have it be reflected in all other places that are referencing it. Otherwise, modifying an object requires a manual process of changing all IP address and mask pairs in the configuration. In addition, you can attach a named object to (or detach a named object from) one or more object groups to ensure that objects are not duplicated but are used efficiently. (A named service object may be attached to or detached from a service object group only, not an object group of another type.)

The object can then be re-used and cannot be deleted if other modules are still referencing it.

When you delete a service object or service group, it is removed from all service groups and access rules where it is used.

If a service group is used in an access rule, do not remove the service group unless you want to delete the access rule. A service group used in an access rule cannot be made empty.

For information about adding or editing a service object, see the “Adding and Editing a Service Object” section on page 13-6 .

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13-5



For information about adding or editing a service group, see the “Adding and Editing a Service Group” section on page 13-7 .

Adding and Editing a Service Object


•

Adding a Service Object, page 13-6

•

Editing a Service Object, page 13-6

Adding a Service Object

To add a service object, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

In the Configuration > Firewall > Objects > Service Object/Group pane, click

Add

.

Choose

Service Object

from the drop-down list.

In the name field, enter a name for the service object. Use characters a to z, A to Z, 0 to 9, a period, a dash, a comma, or an underscore. The name must be 64 characters or fewer.

From the Service Type field, choose the desired type: tcp, udp, icmp, or icmp6 protocol.

(Optional) If you chose tcp or udp as the Service Type, enter the following:

•

•

Destination Port/Range

Source Port/Range—Lists the protocol source ports/ranges.

•

Description—Lists the service group description.

(Optional) If you chose icmp or icmp6 as the Service Type, enter the following:

•

•

ICMP type—Lists the service group ICMP type.


If you chose protocol as the Service Type, enter the following:

•

Protocol—Lists the service group protocol.

•


Click OK to save the configuration.

Editing a Service Object

To edit a service object, perform the following steps:

Step 1

Step 2

Step 3

Go to

Configuration

>

Firewall

>

Objects

>

Service Object/Group

pane.

Select an existing service object under the Name column.

Click

Edit

.

Depending upon the type of a service object you choose edit, the appropriate Edit window appears:

•

Service Object—Edit Service Object window appears.

13-6


OL-20339-01


Step 4

Step 5

•

Service Group—Edit Service Group appears.

•

Protocol Group—Edit Protocol Group window appears.

Enter the necessary changes.



Note

You can also click Delete to delete a service object.

Adding and Editing a Service Group

You can associate multiple service objects into a named service group. You can specify any type of protocol and service in one group or create service groups for each of the following types:

•

•

TCP ports

UDP ports

•

ICMP types

•

IP protocols

Multiple service groups can be nested into a “group of groups” and used as a single group.


•

Adding a Service Group, page 13-7

•

Editing a Service Group, page 13-8

Adding a Service Group

To add a service object or service group, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

In the Configuration > Firewall > Objects > Service Object/Group pane, click

Add

.

Choose

Service Group


The Add Service Group dialog box appears.

In the Name field, enter a name for the new service group. The name can be up to 64 characters in length and must be unique for all object groups. A service group name cannot share a name with a network object group.

In the Description field, enter a description for this service group, up to 200 characters in length.

By default you can add a service group from an existing service/service group. Select the group from the

Name field, and click Add to add the service to the group.

Optionally, you can create a new member:

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13-7



Step 6

Step 7

•

•

Click the

Create new member

radio button.

Select the Service type from the drop-down list.

Enter the destination port/range.

•

•

Enter the source port/range.

Click Add to add the new service.


Editing a Service Group

To edit a service group, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Go to the

Configuration

>

Firewall

>

Objects

>

Service Object/Group

pane.

Select the existing service group that you want to edit, and click

Edit

.

Depending upon the type of a service object you choose edit, the appropriate windows appears:

•

•

Service Object—Edit Service Object window appears.

Service Group—Edit Service Group appears.

•

Protocol Group—Edit Protocol Group window appears.

Enter the necessary changes.


Note

You can also click Delete to delete a service group. When you delete a service group, it is removed from all service groups where it is used. If a service group is used in an access rule, do not remove it. A service group used in an access rule cannot be made empty.

13-8

The Configuration > Global Objects > Service Groups > Add/Edit Service Group dialog box lets you assign services to a service group. This dialog box name matches the type of service group you are adding; for example, if you are adding a TCP service group, the Add/Edit TCP Service Group dialog box is shown.

Fields

•

Group Name—Enter the group name, up to 64 characters in length. The name must be unique for all object groups. A service group name cannot share a name with a network object group.

•

Description—Enter a description of this service group, up to 200 characters in length.

•

•

Existing Service/Service Group—Identifies items that can be added to the service group. Choose from already defined service groups, or choose from a list of commonly used port, type, or protocol names.

–

Service Groups—The title of this table depends on the type of service group you are adding. It includes the defined service groups.

–

Predefined—Lists the predefined ports, types, or protocols.

Create new member—Lets you create a new service group member.


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•

•

•

–

–

–

Service Type—Lets you select the service type for the new service group member. Service types include TCP, UDP, TCP-UDP, ICMP, and protocol.

Destination Port/Range—Lets you enter the destination port or range for the new TCP, UDP, or

TCP-UDP service group member.

Source Port/Range—Lets you enter the source port or range for the new TCP, UDP, or

TCP-UDP service group member.

–

–

ICMP Type—Lets you enter the ICMP type for the new ICMP service group member.

Protocol—Lets you enter the protocol for the new protocol service group member.

Members in Group—Shows items that are already added to the service group.

Add—Adds the selected item to the service group.

Remove—Removes the selected item from the service group.

Browse Service Groups

The Browse Service Groups dialog box lets you choose a service group. This dialog box is used in multiple configuration screens and is named appropriately for your current task. For example, from the

Add/Edit Access Rule dialog box, this dialog box is named “Browse Source Port” or “Browse

Destination Port.”

Fields

•

Add—Adds a service group.

•

•

Edit—Edits the selected service group.

Delete—Deletes the selected service group.

•

•

•

Find—Filters the display to show only matching names. Clicking

Find

opens the Filter field. Click

Find

again to hide the Filter field.

–

Filter field—Enter the name of the service group. The wildcard characters asterisk (*) and question mark (?) are allowed.

–

–

Filter—Runs the filter.

Clear—Clears the Filter field.

Type—Lets you choose the type of service group to show, including TCP, UDP, TCP-UDP, ICMP, and Protocol. To view all types, choose

All

. Typically, the type of rule you configure can only use one type of service group; you cannot select a UDP service group for a TCP access rule.

Name—Shows the name of the service group. Click the plus (+) icon next to the name of an item to expand it. Click the minus (-) icon to collapse the item.

Licensing Requirements for Objects and Groups


Model

All models


Base License.

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13-9


Configuring Regular Expressions

Guidelines and Limitations for Objects and Groups






IPv6 Guidelines

Supports IPv6, with limitations. (See the Additional Guidelines and Limitations, page 13-10 . )


The following guidelines and limitations apply to object groups:

•

Objects and object groups share the same name space.

•

Object groups must have unique names. While you might want to create a network object group named “Engineering” and a service object group named “Engineering,” you need to add an identifier

(or “tag”) to the end of at least one object group name to make it unique. For example, you can use the names “Engineering_admins” and “Engineering_hosts” to make the object group names unique and to aid in identification.

•

You cannot remove an object group or make an object group empty if it is used in a command.

The adaptive security appliance does not support IPv6 nested object groups, so you cannot group an object with IPv6 entities under another IPv6 object group.


A regular expression matches text strings either literally as an exact string, or by using

metacharacters

so that you can match multiple variants of a text string. You can use a regular expression to match the content of certain application traffic; for example, you can match a URL string inside an HTTP packet.

This section describes how to create a regular expression and includes the following topics:

•

Creating a Regular Expression, page 13-10

•

•

•

Building a Regular Expression, page 13-13

Testing a Regular Expression, page 13-14

Creating a Regular Expression Class Map, page 13-15

Creating a Regular Expression

A regular expression matches text strings either literally as an exact string, or by using

metacharacters

so you can match multiple variants of a text string. You can use a regular expression to match the content of certain application traffic; for example, you can match a URL string inside an HTTP packet.

13-10


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Guidelines

Use

Ctrl+V

to escape all of the special characters in the CLI, such as question mark (?) or a tab. For example, type

d[Ctrl+V]?g

to enter

d?g

in the configuration.

See the

regex

command in the


for performance impact information when matching a regular expression to packets.

Note

As an optimization, the adaptive security appliance searches on the deobfuscated URL. Deobfuscation compresses multiple forward slashes (/) into a single slash. For strings that commonly use double slashes, like “http://”, be sure to search for “http:/” instead.

Table 13-1

lists the metacharacters that have special meanings.

Table 13-1 regex Metacharacters

|

.

Character Description

Dot

(

?

*

+

{

[

exp x

}

or

abc

[^

)

]

abc

]

{

x

,}

Subexpression

Alternation

Question mark

Asterisk

Plus

Minimum repeat quantifier

Character class

Negated character class

Notes

Matches any single character. For example,

d.g

matches dog, dag, dtg, and any word that contains those characters, such as doggonnit.

A subexpression segregates characters from surrounding characters, so that you can use other metacharacters on the subexpression. For example,

d(o|a)g

matches dog and dag, but

do|ag

matches do and ag. A subexpression can also be used with repeat quantifiers to differentiate the characters meant for repetition. For example,

ab(xy){3}z

matches abxyxyxyz.

Matches either expression it separates. For example,

dog|cat

matches dog or cat.

A quantifier that indicates that there are 0 or 1 of the previous expression. For example,

lo?se

matches lse or lose.

Note

You must enter

Ctrl+V

and then the question mark or else the help function is invoked.

A quantifier that indicates that there are 0, 1 or any number of the previous expression. For example,

lo*se

matches lse, lose, loose, and so on.

A quantifier that indicates that there is at least 1 of the previous expression. For example,

lo+se

matches lose and loose, but not lse.

Repeat at least

x

times. For example,

ab(xy){2,}z

matches abxyxyz, abxyxyxyz, and so on.

Matches any character in the brackets. For example,

[abc]

matches a, b, or c.

Matches a single character that is not contained within the brackets. For example,

[^abc]

matches any character other than a, b, or c.

[^A-Z]

matches any single character that is not an uppercase letter.

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13-11



Table 13-1

\

\

Character Description

[

a

-

c

]

Character range class

“”

^

char

\r

\n

\t

\f

\x

NN

NNN

regex Metacharacters (continued)

Quotation marks

Caret

Escape character

Character

Carriage return

Newline

Tab

Formfeed

Escaped hexadecimal number

Escaped octal number

Notes

Matches any character in the range.

[a-z]

matches any lowercase letter. You can mix characters and ranges:

[abcq-z]

matches a, b, c, q, r, s, t, u, v, w, x, y, z, and so does [

a-cq-z]

.

The dash (-) character is literal only if it is the last or the first character within the brackets:

[abc-]

or

[-abc]

.

Preserves trailing or leading spaces in the string. For example,

“test”

preserves the leading space when it looks for a match.

Specifies the beginning of a line.

When used with a metacharacter, matches a literal character. For example,

\[

matches the left square bracket.

When character is not a metacharacter, matches the literal character.

Matches a carriage return 0x0d.

Matches a new line 0x0a.

Matches a tab 0x09.

Matches a form feed 0x0c.

Matches an ASCII character using hexadecimal (exactly two digits).

Matches an ASCII character as octal (exactly three digits). For example, the character 040 represents a space.

Detailed Steps

Configuration > Global Objects > Regular Expressions > Add/Edit a Regular Expression Fields

:

•

Name—Enter the name of the regular expression, up to 40 characters in length.

•

Value—Enter the regular expression, up to 100 characters in length. You can enter the text manually, using the metacharacters in

Table 13-1

, or you can click

Build

to use the Building a Regular

Expression dialog box.

•

•

Build—Helps you build a regular expression using the

Building a Regular Expression

dialog box.

Test—Tests a regular expression against some sample text.

Examples

The following example creates two regular expressions for use in an inspection policy map:

regex url_example example\.com

regex url_example2 example2\.com

13-12


OL-20339-01



Building a Regular Expression

The Configuration > Global Objects > Regular Expressions > Add/Edit a Regular Expression > Build

Regular Expression dialog box lets you construct a regular expression out of characters and metacharacters. Fields that insert metacharacters include the metacharacter in parentheses in the field name.

See


for more information about metacharacters.

Detailed Steps

Build Snippet—This area lets you build text snippets of regular text or lets you insert a metacharacter into the Regular Expression field.

•

•

Starts at the beginning of the line (^)—Indicates that the snippet should start at the beginning of a line, using the caret (^) metacharacter. Be sure to insert any snippet with this option at the beginning of the regular expression.

Specify Character String—Enter a text string manually.

–

–

Character String—Enter a text string.

Escape Special Characters—If you entered any metacharacters in your text string that you want to be used literally, check this box to add the backslash (\) escape character before them. for example, if you enter “example.com,” this option converts it to “example\.com”.

•

–

Ignore Case—If you want to match upper and lower case characters, this check box automatically adds text to match both upper and lower case. For example, entering “cats” is converted to “[cC][aA][tT][sS]”.

Specify Character—Lets you specify a metacharacter to insert in the regular expression.

–

–

Negate the character—Specifies not to match the character you identify.

Any character (.)—Inserts the period (.) metacharacter to match any character. For example,

d.g

matches dog, dag, dtg, and any word that contains those characters, such as doggonnit.

–

Character set—Inserts a character set. Text can match any character in the set. Sets include:

[0-9A-Za-z]

[0-9]

[A-Z]

[a-z]

[aeiou]

[\n\f\r\t] (which matches a new line, form feed, carriage return, or a tab)

For example, if you specify [0-9A-Za-z], then this snippet will match any character from A to

Z (upper or lower case) or any digit 0 through 9.

–

–

–

Special character—Inserts a character that requires an escape, including \, ?, *, +, |, ., [, (, or ^.

The escape character is the backslash (\), which is automatically entered when you choose this option.

Whitespace character—Whitespace characters include \n (new line), \f (form feed), \r (carriage return), or \t (tab).

Three digit octal number—Matches an ASCII character as octal (up to three digits). For example, the character \040 represents a space. The backslash (\) is entered automatically.

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13-13



•

•

•

•

–

Two digit hexadecimal number—Matches an ASCII character using hexadecimal (exactly two digits). The backslash (\) is entered automatically.

–

Specified character—Enter any single character.

Snippet Preview—

Display only

. Shows the snippet as it will be entered in the regular expression.

Append Snippet—Adds the snippet to the end of the regular expression.

Append Snippet as Alternate—Adds the snippet to the end of the regular expression separated by a pipe (|), which matches either expression it separates. For example,

dog|cat

matches dog or cat.

•

Insert Snippet at Cursor—Inserts the snippet at the cursor.

Regular Expression—This area includes regular expression text that you can enter manually and build with snippets. You can then select text in the Regular Expression field and apply a quantifier to the selection.

•

Selection Occurrences—Select text in the Regular Expression field, click one of the following options, and then click

Apply to Selection

. For example, if the regular expression is “test me,” and you select “me” and apply

One or more times

, then the regular expression changes to “test (me)+”.

–

Zero or one times (?)—A quantifier that indicates that there are 0 or 1 of the previous expression. For example,

lo?se

matches lse or lose.

–

–

One or more times (+)—A quantifier that indicates that there is at least 1 of the previous expression. For example,

lo+se

matches lose and loose, but not lse.

Any number of times (*)—A quantifier that indicates that there are 0, 1 or any number of the previous expression. For example,

lo*se

matches lse, lose, loose, etc.

–

–

At least—Repeat at least

x

times. For example,

ab(xy){2,}z

matches abxyxyz, abxyxyxyz, etc.

Exactly—Repeat exactly

x

times. For example,

ab(xy){3}z

matches abxyxyxyz.

–

Apply to Selection—Applies the quantifier to the selection.

Test—Tests a regular expression against some sample text.

Testing a Regular Expression

The Configuration > Global Objects > Regular Expressions > Add/Edit a Regular Expression > Test

Regular Expression dialog box lets you test input text against a regular expression to make sure it matches as you intended.

Detailed Steps

•

•

•

•

Regular Expression—Enter the regular expression you want to test. By default, the regular expression you entered in the Add/Edit Regular Expression or Build Regular Expression dialog box is input into this field. If you change the regular expression during your testing, and click

OK

, the changes are inherited by the Add/Edit Regular Expression or Build Regular Expression dialog boxes. Click

Cancel

to dismiss your changes.

Test String—Enter a text string that you expect to match the regular expression.

Test—Tests the Text String against the Regular Expression,

Test Result—

Display only

. Shows if the test succeeded or failed.

13-14


OL-20339-01


Configuring Time Ranges

Creating a Regular Expression Class Map

A regular expression class map identifies one or more regular expressions. You can use a regular expression class map to match the content of certain traffic; for example, you can match URL strings inside HTTP packets.

Detailed Steps

Configuration > Global Objects > Regular Expressions > Add/Edit Regular Expression Class Map dialog box Fields:

•

Name—Enter a name for the class map, up to 40 characters in length. The name “class-default” is reserved. All types of class maps use the same name space, so you cannot reuse a name already used by another type of class map.

•

•

Description—Enter a description, up to 200 characters in length.

Available Regular Expressions—Lists the regular expressions that are not yet assigned to the class map.

•

•

–

–

Edit—Edits the selected regular expression.

New—Creates a new regular expression.

Add—Adds the selected regular expression to the class map.

Remove—Removes the selected regular expression from the class map.

•

Configured Match Conditions—Shows the regular expressions in this class map, along with the match type.

–

Match Type—Shows the match type, which for regular expressions is always a positive match type (shown by the icon with the equal sign (=)) the criteria. (Inspection class maps allow you to create negative matches as well (shown by the icon with the red circle)). If more than one regular expression is in the class map, then each match type icon appears with “OR” next it, to indicate that this class map is a “match any” class map; traffic matches the class map if only one regular expression is matched.

–

Regular Expression—Lists the regular expression names in this class map.


Use the Configuration > Global Objects > Time Ranges pane to create a reusable component that defines starting and ending times that can be applied to various security features. Once you have defined a time range, you can select the time range and apply it to different options that require scheduling.

The time range feature lets you define a time range that you can attach to traffic rules, or an action. For example, you can attach an access list to a time range to restrict access to the adaptive security appliance.

A time range consists of a start time, an end time, and optional recurring entries.

For detailed steps on adding a time range to an access rule, see the

“Adding a Time Range to an Access

Rule” section on page 13-16 .

Note

Creating a time range does not restrict access to the device. This pane defines the time range only.

OL-20339-01


13-15



Fields

•

Name—Specifies the name of the time range.

•

Start Time—Specifies when the time range begins.

•

•

End Time—Specifies when the time range ends.

Recurring Entries—Specifies further constraints of active time of the range within the start and stop time specified.

Add/Edit Time Range

The Configuration > Global Objects > Time Ranges > Add/Edit Time Range dialog box lets you define specific times and dates that you can attach to an action. For example, you can attach an access list to a time range to restrict access to the adaptive security appliance. The time range relies on the system clock of the adaptive security appliance; however, the feature works best with NTP synchronization. For detailed steps on adding a time range to an IPv6 ACL, see the

“Configuring Access Rules” section on page 30-7 .

Adding a Time Range to an Access Rule

You can add a time range to an ACL to specify when traffic can be allowed or denied through an interface.

To add a time range to an ACL, perform the following steps:

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 1

Step 2

Step 3

Step 4

Step 11

Step 12

Step 13

Choose

Configuration

>

Firewall

>

Access Rules

.

Choose the access list type by clicking the

IPv4 Only

, the

IPv6 Only

, or the

IPV6 and IPv6

radio button.

Click

Add

. The Add Access Rule window appears.

From the Interface drop down list, choose the desired interface.

The management interface is for management only and cannot be used to configure an access rule.

Click

Permit

or

Deny

to permit or deny the action.

In the Source field, enter an IP address.

In the Destination field, enter an IP address.

Select the service type.

Click

More Options

to expand the list.

To the right of the Time Range drop down list, click the browse button.

The Browse Time Range window appears.

Click

Add

.

The Add Time Range window appears.

In the Time Range Name field, enter a time range name, with no spaces.

Choose the Start Time and the End Time by doing one of the following:

a.

Allow the default settings, in which the Start Now and the Never End radio buttons are checked.

b.

Apply a specific time range by clicking the

Start at

and

End at

radio buttons and selecting the specified start and stop times from the lists.


13-16 OL-20339-01



Step 14

Step 15

Step 16

The time range is inclusive of the times that you enter.

(Optional) To specify additional time constraints for the time range, such as specifying the days of the week or the recurring weekly interval in which the time range will be active, click

Add

, and do one of the following:

a.

Click

Specify days of the week and times on which this recurring range will be active

, and choose the days and times from the lists, and click

OK

.

b.

Click

Specify a weekly interval when this recurring range will be active

, and choose the days and times from the lists, and click

OK

.

Click OK to apply the time range.

Click OK to apply the access rule.

OL-20339-01

Note


Add/Edit Time Range Field Descriptions

•

Time Range Name—Specifies the name of the time range. The name cannot contain a space or quotation mark, and must begin with a letter or number.

•

•

Start now/Started—Specifies either that the time range begin immediately or that the time range has begun already. The button label changes based on the Add/Edit state of the time range configuration.

If you are adding a new time range, the button displays “Start Now.” If you are editing a time range for which a fixed start time has already been defined, the button displays “Start Now.” When editing a time range for which there is no fixed start time, the button displays “Started.”

Start at—Specifies when the time range begins.

–

–

–

–

Month—Specifies the month, in the range of January through December.

Day—Specifies the day, in the range of 01 through 31.

Year—Specifies the year, in the range of 1993 through 2035.

Hour—Specifies the hour, in the range of 00 through 23.

•

•

–

Minute—Specifies the minute, in the range of 00 through 59.

Never end—Specifies that there is no end to the time range.

End at (inclusive)—Specifies when the time range ends. The end time specified is inclusive. For example, if you specified that the time range expire at 11:30, the time range is active through 11:30 and 59 seconds. In this case, the time range expires when 11:31 begins.

–

Month—Specifies the month, in the range of January through December.

•

–

–

–

–

Day—Specifies the day, in the range of 01 through 31.

Year—Specifies the year, in the range of 1993 through 2035.

Hour—Specifies the hour, in the range of 00 through 23.

Minute—Specifies the minute, in the range of 00 through 59.

Recurring Time Ranges—Configures daily or weekly time ranges.

–

Add—Adds a recurring time range.

–

–

Edit—Edits the selected recurring time range.

Delete—Deletes the selected recurring time range.


13-17



Add/Edit Recurring Time Range

The Configuration > Global Objects > Time Ranges > Add/Edit Time Range >

Add/Edit Periodic Time Range pane lets you fine time ranges further by letting you configure them on a daily or weekly basis.

For detailed steps on adding a recurring time range to an access rule, see the

“Adding a Time Range to an Access Rule” section on page 13-16

.

Note


Add/Edit Recurring Time Range Field Descriptions

•

Days of the week

–

–

Every day—Specifies every day of the week.

Weekdays—Specifies Monday through Friday.

–

–

Weekends—Specifies Saturday and Sunday.

On these days of the week—Lets you choose specific days of the week.

–

–

Daily Start Time—Specifies the hour and the minute that the time range begins.

Daily End Time (inclusive) area—Specifies the hour and the minute that the time range ends.

The end time specified is inclusive.

•

Weekly Interval

–

From—Lists the day of the week, Monday through Sunday.

–

–

Through—Lists the day of the week, Monday through Sunday.

Hour—Lists the hour, in the range of 00 through 23.

–

Minute—Lists the minute, in the range of 00 through 59.

13-18


OL-20339-01

C H A P T E R

14

Configuring Public Servers

This section describes how to configure public servers, and includes the following topics:

•

Public Server Overview, page 14-1

•

•

Adding a Public Server, page 14-2

Editing a Public Server, page 14-3

Public Server Overview

While the basic functions of a firewall are to protect inside networks from unauthorized access by users on an outside network or to protect inside networks from each other, these functions involve multiple configurations. These configurations include configuring inside DMZ interfaces, creating access rules, creating NAT or PAT rules, and configuring application inspection.

ASDM provides the Public Servers pane in the Configuration > Firewall > Public Servers pane so that an administrator can enable various application servers to be accessed by internal and external users.

When selected, this pane displays a list of public servers. internal and external addresses, the interfaces to which the internal or external addresses apply, the ability to translate the addresses, and the service that is exposed.

In this pane you can add, edit, delete, or modify existing public servers.

Fields

•

Add—Adds a public server.

•

•

Edit—Edits a a public server group.

Delete—Deletes a specified public server.

•

•

Apply—Applies the changes that have been made.

Reset—Resets the security appliance to the previous configuration.


14-1 OL-20339-01

Chapter 14 Configuring Public Servers

Adding a Public Server

Adding a Public Server

You can add a public server that enables static NAT and creates a fixed translation of a real address to a mapped address, or you can add a public server that enables static NAT with port address translation and lets you specify a real and mapped protocol (TCP or UDP) and port.

•

Adding a Public Server that Enables Static NAT, page 14-2

•

Adding a Public Server that Enables Static NAT with Port Address Translation, page 14-2

Adding a Public Server that Enables Static NAT

To add a public server that creates a fixed translation of a real address to a mapped address, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

In the Configuration > Firewall > Public Servers pane, click

Add

to add a new server.

The Add Public Server dialog box appears.

From the Private Interface drop-down menu, select the name of the private interface to which the real server is connected.

In the Private IP address field, enter the real IP address of the server (IPv4 only).

In the Private Service field, click

Browse ...

to display the Browse Service dialog box, choose the actual service that is exposed to the outside, and click

OK

.

Optionally, from the Browse Service dialog box you can click

Add

to create a new service or service group. Multiple services from various ports can be opened to the outside. For more information about service objects and service groups, see the

“Configuring Service Objects and Service Groups” section on page 13-5

.

From the Public Interface drop-down menu, enter the interface through which users from the outside can access the real server.

In the Public Address field, enter the mapped IP address of the server, which is the address that is seen by the outside user.

(Optional) To enable static PAT, check the

Specify if Public Service is different from private service

check box .

Click

OK

. The configuration appears in the main pane.

Click

Apply

to generate static NAT and a corresponding access rule for the traffic flow and to save the configuration.

For information about static NAT, see the “Information About Static NAT” section on page 26-3

.

Adding a Public Server that Enables Static NAT with Port Address Translation

To add a public server that lets you specify a real and mapped protocol (TCP or UDP) to a port, perform the following steps:

Step 1


Add

to add a new server.

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Editing a Public Server

Step 2

Step 3

Step 4

The Add Public Server dialog box appears.

From the Private Interface drop-down menu, select the name of the private interface to which the real server is connected.

In the Private IP address field, enter the real IP address of the server (IPv4 only).

In the Private Service field, click

Browse ...

to display the Browse Service dialog box, choose the actual service that is exposed to the outside, and click

OK

.

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Optionally, from the Browse Service dialog box you can click

Add

to create a new service or service group. Multiple services from various ports can be opened to the outside. For more information about

service objects and service groups, see the “Configuring Service Objects and Service Groups” section on page 13-5 .

From the Public Interface drop-down menu, enter the interface through which users from the outside can access the real server.

In the Public Address field, enter the mapped IP address of the server, which is the address that is seen by the outside user.

Check the

Specify Public Service if different from Private Service

check box to enable static PAT.

In the Public Service field, enter the mapped protocol (TCP or UDP only) or click

Browse ...

to select a protocol from the list.

Click

OK

.

Click

Apply

to generate static NAT with port address translation and a corresponding access rule for the traffic flow and to save the configuration.

For information about static NAT with port address translation, see the

“Information About Static NAT with Port Translation” section on page 26-3 .


To edit a public server, perform the following steps:

Step 1

Step 2

Step 3


Edit

to edit an object, or choose an existing public server, and click

Edit

.

The Edit Public Server dialog box appears.

Make any necessary changes to the following values:

•

•

•

•

•

•

Private Interface—The interface to which the real server is connected.

Private IP Address—The real IP address of the server.

Private Service—The actual service that is running on the real server.

Public Interface—The interface through which outside users can access the real server.

Public Address.—The IP address that is seen by outside users.

Public Service—The service that is running on the translated address.

Click

OK

.

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P

A R T

3

Configuring ACLs

Using the ACL Manager

C H A P T E R

15

The ACL Manager dialog box lets you define access control lists (ACLs) to control the access of a specific host or network to another host/network, including the protocol or port that can be used.

You can configure ACLs (access control lists) to apply to user sessions. These are filters that permit or deny user access to specific networks, subnets, hosts, and web servers.

•

•

•

If you do not define any filters, all connections are permitted.

The adaptive security appliance supports only an inbound ACL on an interface.

At the end of each ACL, there is an implicit, unwritten rule that denies all traffic that is not permitted. If traffic is not explicitly permitted by an access control entry (ACE), the adaptive security appliance denies it. ACEs are referred to as rules in this section.

Standard ACL

This pane provides summary information about standard ACLs and lets you add or edit ACLs and ACEs.

Standard access lists identify the destination IP addresses of OSPF routes and can be used in a route map for OSPF redistribution. Standard access lists cannot be applied to interfaces to control traffic.

Fields

•

Add—Lets you add a new ACL. When you highlight an existing ACL, it lets you add a new ACE for that ACL.

•

•

Add IPv6—Lets you add an ACL for traffic with IPv6 addresses.

Add ACE—Lets you add an access control entry (ACE), or access rule, specifying the source address, destination address, and service.

•

•

•

•

Edit—Opens the Edit ACE dialog box, in which you can change an existing access control list rule.

Delete—Removes an ACL or ACE. There is no confirmation or undo.

Move Up/Move Down—Changes the position of a rule in the ACL Manager table.

•

•

•

•

Cut—Removes the selection from the ACL Manager table and places it on the clipboard.

Copy—Places a copy of the selection on the clipboard.

Paste—Opens the Paste ACE dialog box, in which you can create a new ACL rule from an existing rule.

No—Indicates the order of evaluation for the rule. Implicit rules are not numbered, but are represented by a hyphen.

Address—Displays the IP address or URL of the application or service to which the ACE applies.


OL-20339-01 15-1

Chapter 15 Using the ACL Manager

•

•

•

Action—Determines the action typpe of the new rule. Select either permit or deny.

–

–

Permit—Permits all matching traffic.

Deny—Denies all matching traffic.

Description—Shows the description you typed when you added the rule. An implicit rule includes the following description: “Implicit outbound rule.”

More Options—Lets you specify the source service (TCP or UDP only), a time range, and logging interval.

Extended ACL

This pane provides summary information about extended ACLs, and lets you add or edit ACLs and

ACEs.

Fields

•


•


•

•

•

•





•

•

•

•

•

•

•



Enabled—Enables or disables a rule. Implicit rules cannot be disabled.

Source—Specifies the IP addresses (Host/Network) that are permitted or denied to send traffic to the IP addresses listed in the Destination column. In detail mode (see the Show Detail radio button), an address column might contain an interface name with the word any, such as inside: any. This means that any host on the inside interface is affected by the rule.

Destination—Specifies the IP addresses (Host/Network) that are permitted or denied to send traffic to the IP addresses listed in the Source column. An address column might contain an interface name with the word any, such as outside: any. This means that any host on the outside interface is affected by the rule. An address column might also contain IP addresses; for example

209.165.201.1-209.165.201.30. These addresses are translated addresses. When an inside host makes a connection to an outside host, the firewall maps the address of the inside host to an address from the pool. After a host creates an outbound connection, the firewall maintains this address mapping. The address mapping structure is called an xlate, and remains in memory for a period of time. During this time, outside hosts can initiate connections to the inside host using the translated address from the pool, if allowed by the ACL. Normally, outside-to-inside connections require a static translation so that the inside host always uses the same IP address.

Service—Names the service and protocol specified by the rule.

Action—Specifies whether this filter permits or denies traffic flow.

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•

•

•

Logging—Shows the logging level and the interval in seconds between log messages (if you enable logging for the ACL). To set logging options, including enabling and disabling logging, right-click this column, and click Edit Log Option. The Log Options dialog box appears.

Time—Specifies the name of the time range to be applied in this rule.


Modes

The following table shows the modes in which this feature is available:

Firewall Mode

Routed

Security Context

Transparent Single

Multiple

Context

•

—

•

—

System

—

Add/Edit/Paste ACE

The Add/Edit/Paste ACE dialog box lets you create a new extended access list rule, or modify an existing rule. The Paste option becomes available only when you cut or copy a rule.

Fields

•

Action—Determines the action type of the new rule. Select either permit or deny.

–

–



•

•

Source/Destination—Specifies the source or destination type and, depending on that type, the other relevant parameters describing the source or destination host/network IP Address. Possible values are: any, IP address, Network Object Group, and Interface IP. The availability of subsequent fields depends upon the value of the Type field:

–

any—Specifies that the source or destination host/network can be any type. For this value of the

Type field, there are no additional fields in the Source or Destination area.

–

–

IP Address—Specifies the source or destination host or network IP address. Both IPv4 and IPv6 addresses are supported. With this selection, the IP Address, ellipsis button, and Netmask fields become available. Choose an IP address or host name from the drop-down list in the IP Address field or click the ellipsis (...) button to browse for an IP address or name. Select a network mask from the drop-down list.

Network Object Group—Specifies the name of the network object group. Choose a name from the drop-down list or click the ellipsis (...) button to browse for a network object group name.

–

Interface IP—Specifies the interface on which the host or network resides. Select an interface from the drop-down list. The default values are inside and outside. There is no browse function.

Protocol and Service—Specifies the protocol and service to which this ACE filter applies. Service groups let you identify multiple non-contiguous port numbers that you want the ACL to match. For example, if you want to filter HTTP, FTP, and port numbers 5, 8, and 9, define a service group that includes all these ports. Without service groups, you would have to create a separate rule for each port.

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15-3


•

•

You can create service groups for TCP, UDP, TCP-UDP, ICMP, and other protocols. A service group with the TCP-UDP protocol contains services, ports, and ranges that might use either the TCP or

UDP protocol.

–

–

Protocol—Selects the protocol to which this rule applies. Possible values are ip, tcp, udp, icmp, and other. The remaining available fields in the Protocol and Service area depend upon the protocol you select. The next few bullets describe the consequences of each of these selections:

Protocol: TCP and UDP—Selects the TCP/UDP protocol for the rule. The Source Port and

Destination Port areas allow you to specify the ports that the ACL uses to match packets.

–

–

Source Port/Destination Port—(

Available only for TCP and UDP protocols

) Specifies an operator and a port number, a range of ports, or a well-known service name from a list of services, such as HTTP or FTP. The operator list specifies how the ACL matches the port.

Choose one of the following operators: = (equals the port number), not = (does not equal the port number), > (greater than the port number), < (less than the port number), range (equal to one of the port numbers in the range).

Group—(


) Selects a source port service group. The

Browse (...) button opens the Browse Source Port or Browse Destination Port dialog box.

–

–

Protocol: ICMP—Lets you choose an ICMP type or ICMP group from a preconfigured list or browse (...) for an ICMP group. The Browse button opens the Browse ICMP dialog box.

Protocol: IP—Specifies the IP protocol for the rule in the IP protocol box. No other fields are available when you make this selection.

–

Protocol: Other—Lets you choose a protocol from a drop-down list, choose a protocol group from a drop-down list, or browse for a protocol group. The Browse (...) button opens the Browse

Other dialog box.

Rule Flow Diagram—(

Display only

) Provides a graphical representation of the configured rule flow.

This same diagram appears on the ACL Manager dialog box unless you explicitly close that display.

Options—Sets optional features for this rule, including logging parameters, time ranges, and description.

–

Logging—Enables or disables logging or specifies the use of the default logging settings. If logging is enabled, the Syslog Level and Log Interval fields become available.

–

–

Syslog Level—Selects the level of logging activity. The default is Informational.

Log Interval—Specifies the interval for permit and deny logging. The default is 300 seconds.

The range is 1 through 6000 seconds.

–

–

Time Range—Selects the name of the time range to use with this rule. The default is (any). Click the Browse (...) button to open the Browse Time Range dialog box to select or add a time range.

Description—(

Optional

) Provides a brief description of this rule. A description line can be up to 100 characters long, but you can break a description into multiple lines.

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Adding a WebtypeACL

C H A P T E R

16

Webtype ACLs are added to a configuration that supports filtering for clientless SSL VPN. This chapter describes how to add an ACLto the configuration that supports filtering for WebVPN.


•

•

•

•

•

Licensing Requirements for Webtype ACLs, page 16-1



Using Webtype ACLs, page 16-2

Feature History for Webtype Access Lists, page 16-5

Licensing Requirements for Webtype ACLs


Model

All models


Base License.


This section includes the guidelines and limitations for this feature:

•

•

•

Context Mode Guidelines, page 16-1

Firewall Mode Guidelines, page 16-1

Additional Guidelines and Limitations, page 16-2






16-1 OL-20339-01


Chapter 16 Adding a WebtypeACL

IPv6 Guidelines

Supports IPv6.


The following guidelines and limitations apply to Webtype ACLs:

•

Smart tunnel ACEs filter on a per-server basis only, so you cannot create smart tunnel ACEs to permit or deny access to directories or to permit or deny access to specific smart tunnel-enabled applications.


Table 16-1 lists the default settings for Webtype access lists parameters.

Table 16-1 Default Webtype Access List Parameters

Parameters deny log

Default

The adaptive security appliance denies all packets on the originating interface unless you specifically permit access.

Access list logging generates system log message

106023 for denied packets. Deny packets must be present to log denied packets.

Using Webtype ACLs


•

•

Task Flow for Configuring Webtype ACLs, page 16-2

Adding a Webtype ACL and ACE, page 16-2

•

•

Editing Webtype ACLs and ACEs, page 16-4

Deleting Webtype ACLs and ACEs, page 16-5

Task Flow for Configuring Webtype ACLs

Use the following guidelines to create and implement an ACL:

•

Create an ACL by adding an ACE and applying an ACL name. See the

“Using Webtype ACLs” section on page 16-2 .

•

Apply the ACL to an interface. See the

“Configuring Access Rules” section on page 30-7


Adding a Webtype ACL and ACE

You must first create the webtype ACL and then add an ACE to the ACL.

16-2


OL-20339-01



Note

Smart tunnel ACEs filter on a per-server basis only, so you cannot create smart tunnel ACEs to permit or deny access to directories or to permit or deny access to specific smart tunnel-enabled applications.

To configure a webtype ACL, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Choose

Configuration > Remote Access VPN > Clientless SSL VPN Access > Advanced > Web

ACLs

.

Click

Add

, and choose one of the following ACL types to add:

•

•

Add ACL

Add IPv6 ACL

The Add ACL dialog box appears.

Enter a name for the ACL (with no spaces), and click

OK

.

To add an entry to the list that you just created, click

Add

, and choose

Add ACE


In the Action field, click the radio button next to the desired action:

•

•

Permit—Permits access if the conditions are matched.

Deny—Denies access if the conditions are matched.

Note

The end of every ACL has an implicit deny rule.

Step 6

Step 7

In the filter field, you can either filter on a URL or filter on an address and Service.

a.

To filter on a URL, choose the URL prefix from the drop-down list, and enter the URL>

Wildcard characters can be used in the URL field:

–

An asterisk * matches none or any number of characters.

–

–

A question mark ? matches any one character exactly.

Square brackets [] are range operators, matching any character in the range. For example, to match both http://www.cisco.com:80/ and http://www.cisco.com:81/, enter the following:

http://www.cisco.com:8[01]/ b.

To filter on an address and service, click the

Filter address and service

radio button, and enter the appropriate values.

Wildcard characters can be used in the with regular expression in the address field:

–

–

An asterisk * matches none or any number of characters.

A question mark ? matches any one character exactly.

–

Square brackets [] are range operators, matching any character in the range. For example to permit a range of IP addresses from 10.2.2.20 through 10.2.2.31, enter the following:

10.2.2.[20-31]

You can also browse for the address and service by clicking the browse buttons at the end of the fields.

(Optional) Logging is enabled by default. You can disable logging by unchecking the check box, or you can change the logging level from the drop-down list. The default logging level is Informational.

For more information about logging options, see the Log Options section on page 21-29.

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16-3



Step 8

Step 9

Step 10

Step 11

(Optional) If you changed the logging level from the default setting, you can specify the logging interval by clicking

More Options

to expand the list.

Valid values are from 1 through 6000 seconds. The default is 300 seconds.

(Optional) To add a time range to your access rule that specifies when traffic can be allowed or denied, click

More Options

to expand the list.

a.

d.

e.

b.

c.

f.

To the right of the Time Range drop-down list, click the browse button.

The Browse Time Range dialog box appears.

Click

Add

.

The Add Time Range dialog box appears.


Enter the Start Time and the End Time.

g.

To specify additional time constraints for the time range, such as specifying the days of the week or the recurring weekly interval in which the time range will be active, click

Add

, and specify the desired values.

Click

OK

to apply the optional time range specifications.

Click

Apply


Note

After you add ACLs, you can click the following radio buttons to filter which ACLs appear in the main pane: IPv4 andIPv6, IPv4 only, or IPv6 Only.

Editing Webtype ACLs and ACEs

To edit a webtype ACL or ACT, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Choose

Configuration

>

Remote Access VPN

>

Clientless SSL VPN Access

>

Advanced

>

Web

ACLs

.

Choose the ACL type to edit by clicking one of the following radio buttons:

•

•

IPv4 and IPv6

— Shows ACLs that have both IPv4 and IPv6 addresses only.

IPv4 Only

—Shows ACLs that have IPv4 type addresses only.

• IPv6 Only

—Shows access rules that have IPv6 type addresses only.

The main Access Rule Pane displays the available interfaces for the chosen rule type.

Select the ACE to edit, and make any changes to the values.

For more information about specific values, see the

“Adding a Webtype ACL and ACE” section on page 16-2 .

Click

OK

.

Click

Apply


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Feature History for Webtype Access Lists

Deleting Webtype ACLs and ACEs

To delete a webtype ACE, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Choose

Configuration

>


>


>

Advanced

>

Web

ACLs

.

Choose the ACL type to edit by clicking one of the following radio buttons:

•

•

IPv4 and IPv6

— Shows ACLs that have both IPv4 and IPv6 addresses only.

IPv4 Only

—Shows ACLs that have IPv4 type addresses only.

• IPv6 Only

—Shows access rules that have IPv6 type addresses only.

The main Access Rule Pane displays the available interfaces for the chosen rule type.

Select the ACE to delete.

If you select a specific ACE, only that ACE is deleted. If you select an ACL, that ACL and all of the

ACEs under it are deleted.

Click

Delete

.

The selected items are removed from the viewing pane.

Note

If you deleted an item in error and want to restore it to your configuration, click

Reset

before you click Apply. The deleted item reappears in the viewing pane.

Step 5

Click

Apply

to save the change to the configuration.


Table 16-2


Table 16-2 Feature History for Webtype Access Lists

Feature Name

Webtype access lists

Releases

7.0


Webtype ACLs are access lists that are added to a configuration that supports filtering for clientless SSL

VPN.

The feature was introduced.

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16-5



16-6


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OL-20339-01


16-7



16-8


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OL-20339-01


16-9



16-10


OL-20339-01

Adding a StandardACL

C H A P T E R

17

This chapter describes how to configure a standard ACL and includes the following sections:

•

Information About Standard ACLs, page 17-1

•

•

•

•

•

Licensing Requirements for Standard ACLs, page 17-1



Adding Standard ACLs, page 17-2

Feature History for Standard ACLs, page 17-4

Information About Standard ACLs

Standard access lists identify the destination IP addresses of OSPF routes and can be used in a route map for OSPF redistribution. Standard access lists cannot be applied to interfaces to control traffic.

Licensing Requirements for Standard ACLs


Model

All models


Base License.



•

•

•

•

Context Mode Guidelines, page 17-2

Firewall Mode Guidelines, page 17-2

IPv6 Guidelines, page 17-2

Additional Guidelines and Limitations, page 17-2


17-1 OL-20339-01


Chapter 17 Adding a StandardACL


Supported in single context mode only.



IPv6 Guidelines

Supports IPv6.


The following guidelines and limitations apply for standard ACLs:

•

Standard ACLs identify the destination IP addresses (not source addresses) of OSPF routes and can be used in a route map for OSPF redistribution. Standard ACLs cannot be applied to interfaces to control traffic.

•

When specifying a source, local, or destination address, use the following guidelines:

–

Use a 32-bit quantity in four-part, dotted-decimal format.

•


Table 17-1 lists the default settings for standard ACL parameters.

Table 17-1 Default Standard Access List Parameters

Parameters

deny

Default

The adaptive security appliance denies all packets on the originating interface unless you specifically permit access.

Access list logging generates system log message

106023 for denied packets. Deny packets must be present to log denied packets.

Adding Standard ACLs


•

•

•

•, page 17-2

Using Standard ACLs, page 17-3

, page 17-4

•

17-2


OL-20339-01


Adding Standard ACLs

Using Standard ACLs

Standard ACLs identify the destination IP addresses (not source addresses) of OSPF routes and can be used in a route map for OSPF redistribution. Standard ACLs cannot be applied to interfaces to control traffic.


•

•

•

Adding a Standard ACL, page 17-3

Adding an ACE to a Standard ACL, page 17-3

Editing an ACE in a Standard ACL, page 17-4

Adding a Standard ACL

To add a standard ACL to your configuration, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Choose

Configuration

>

Firewall

>

Advanced

>

Standard ACL.

Click

Add

, and from the drop-down list, choose

Add ACL

.

In the Add ACL dialog box, add a name or number (without spaces) to identify the ACL.

Click

OK

The ACL name appears in the main pane.

You may add additional ACLs.

Click

Apply

to save the ACLs to your configuration.

You can now add one or more ACEs to the newly created ACL.

To add an ACE, see the

“Adding an ACE to a Standard ACL” section on page 17-3 .

Adding an ACE to a Standard ACL

Before you can add an ACE to a configuration, you must first add an ACL. For information about adding a standard ACL, see the

“Adding a Standard ACL” section on page 17-3 . For information about editing

ACEs, see the

“Editing an ACE in a Standard ACL” section on page 17-4

To add an ACE to an ACL that exists in your configuration, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Choose

Configuration

>

Firewall

>

Advanced

>

Standard ACL.

In the main pane, select the ACL for which you want to add an ACE.

Click

Add

, and choose

Add ACE


The Add ACE dialog box appears.

(Optional) To specify the placement of the new ACE, select an existing ACE, and click Insert... to add the ACE before the selected ACE, or click Insert After... to add the ACE after the selected ACE.

Click one of the following radio buttons to choose an action:

•

•

Permit

—Permits access if the conditions are matched.

Deny

—Denies access if the conditions are matched.

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17-3


Feature History for Standard ACLs

Step 6

Step 7

Step 8

Step 9

In the Address field, enter the IP address of the destination to which you want to perform or deny access.

You can also browse for the address of a network object by clicking the ellipsis at the end of the Address field.

(Optional) In the Description field, enter a description that makes an ACE easier to understand.

The description can contain multiple lines; however, each line can be no more than 100 characters in length.

Click

OK

.

The newly created ACE appears under the ACL.

Click

Apply

to save the ACE to your configuration.

Editing an ACE in a Standard ACL

To edit an ACE in a standard ACL, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Choose

Configuration

>

Firewall

>

Advanced

>

Standard ACL.

In the main pane, select the existing ACE that you want to edit.

Click

Edit.

The Edit ACE dialog box appears.

Enter the desired changes.

Click

OK

.

Feature History for Standard ACLs


Table 17-2

Feature Name

Standard ACLs

Feature History for Standard Access Lists

Releases

7.0


Standard ACLs identify the destination IP addresses of

OSPF routes, which can be used in a route map for OSPF redistribution.


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P

A R T

4

Configuring IP Routing

Information About

Routing

C H A P T E R

18

This chapter describes underlying concepts of how routing behaves within the adaptive security appliance, and the routing protocols that are supported.

The chapter includes the following sections:

•

•

•

•

•

•

Information About Routing, page 18-1

How Routing Behaves Within the Adaptive Security Appliance, page 18-4

Supported Internet Protocols for Routing, page 18-5

Information About the Routing Table, page 18-5

Information About IPv6 Support, page 18-8

Disabling Proxy ARPs, page 18-11


Routing is the act of moving information across an internetwork from a source to a destination. Along the way, at least one intermediate node typically is encountered. Routing involves two basic activities: determining optimal routing paths and transporting information groups (typically called packets) through an internetwork. In the context of the routing process, the latter of these is referred to as packet switching. Although packet switching is relatively straightforward, path determination can be very complex.

Switching

Switching algorithms is relatively simple; it is the same for most routing protocols. In most cases, a host determines that it must send a packet to another host. Having acquired a router's address by some means, the source host sends a packet addressed specifically to a router’s physical (Media Access Control

[MAC]-layer) address, this time with the protocol (network layer) address of the destination host.

As it examines the packet's destination protocol address, the router determines that it either knows or does not know how to forward the packet to the next hop. If the router does not know how to forward the packet, it typically drops the packet. If the router knows how to forward the packet, however, it changes the destination physical address to that of the next hop and transmits the packet.

The next hop may be the ultimate destination host. If not, the next hop is usually another router, which executes the same switching decision process. As the packet moves through the internetwork, its physical address changes, but its protocol address remains constant.

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Chapter 18 Information About Routing


Path Determination

Routing protocols use metrics to evaluate what path will be the best for a packet to travel. A metric is a standard of measurement, such as path bandwidth, that is used by routing algorithms to determine the optimal path to a destination. To aid the process of path determination, routing algorithms initialize and maintain routing tables, which contain route information. Route information varies depending on the routing algorithm used.

Routing algorithms fill routing tables with a variety of information. Destination/next hop associations tell a router that a particular destination can be reached optimally by sending the packet to a particular router representing the “next hop” on the way to the final destination. When a router receives an incoming packet, it checks the destination address and attempts to associate this address with a next hop.

Routing tables also can contain other information, such as data about the desirability of a path. Routers compare metrics to determine optimal routes, and these metrics differ depending on the design of the routing algorithm used.

Routers communicate with one another and maintain their routing tables through the transmission of a variety of messages. The routing update message is one such message that generally consists of all or a portion of a routing table. By analyzing routing updates from all other routers, a router can build a detailed picture of network topology. A link-state advertisement, another example of a message sent between routers, informs other routers of the state of the sender's links. Link information also can be used to build a complete picture of network topology to enable routers to determine optimal routes to network destinations.

Note

Asymmetric routing is not supported on the adaptive security appliance.

Supported Route Types

There are several types of route types that a router can use. The adaptive security appliance uses the following route types:

•

•

•

•

Static Versus Dynamic, page 18-2

Single-Path Versus Multipath, page 18-3

Flat Versus Hierarchical, page 18-3

Link-State Versus Distance Vector, page 18-3

Static Versus Dynamic

Static routing algorithms are hardly algorithms at all, but are table mappings established by the network administrator before the beginning of routing. These mappings do not change unless the network administrator alters them. Algorithms that use static routes are simple to design and work well in environments where network traffic is relatively predictable and where network design is relatively simple.

Because static routing systems cannot react to network changes, they generally are considered unsuitable for today's large, constantly changing networks. Most of the dominant routing algorithms today are dynamic routing algorithms, which adjust to changing network circumstances by analyzing incoming routing update messages. If the message indicates that a network change has occurred, the routing software recalculates routes and sends out new routing update messages. These messages permeate the network, stimulating routers to rerun their algorithms and change their routing tables accordingly.

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Dynamic routing algorithms can be supplemented with static routes where appropriate. A router of last resort (a router to which all unroutable packets are sent), for example, can be designated to act as a repository for all unroutable packets, ensuring that all messages are at least handled in some way.

Note

There is no dynamic routing support in multi-context mode. Because of this, there is no route tracking.

Single-Path Versus Multipath

Some sophisticated routing protocols support multiple paths to the same destination. Unlike single-path algorithms, these multipath algorithms permit traffic multiplexing over multiple lines. The advantages of multipath algorithms are obvious: They can provide substantially better throughput and reliability.

This is generally called load sharing.

Flat Versus Hierarchical

Some routing algorithms operate in a flat space, while others use routing hierarchies. In a flat routing system, the routers are peers of all others. In a hierarchical routing system, some routers form what amounts to a routing backbone. Packets from nonbackbone routers travel to the backbone routers, where they are sent through the backbone until they reach the general area of the destination. At this point, they travel from the last backbone router through one or more nonbackbone routers to the final destination.

Routing systems often designate logical groups of nodes, called domains, autonomous systems, or areas.

In hierarchical systems, some routers in a domain can communicate with routers in other domains, while others can communicate only with routers within their domain. In very large networks, additional hierarchical levels may exist, with routers at the highest hierarchical level forming the routing backbone.

The primary advantage of hierarchical routing is that it mimics the organization of most companies and therefore supports their traffic patterns well. Most network communication occurs within small company groups (domains). Because intradomain routers need to know only about other routers within their domain, their routing algorithms can be simplified, and, depending on the routing algorithm being used, routing update traffic can be reduced accordingly.

Link-State Versus Distance Vector

Link-state algorithms (also known as shortest path first algorithms) flood routing information to all nodes in the internetwork. Each router, however, sends only the portion of the routing table that describes the state of its own links. In link-state algorithms, each router builds a picture of the entire network in its routing tables. Distance vector algorithms (also known as Bellman-Ford algorithms) call for each router to send all or some portion of its routing table, but only to its neighbors. In essence, link-state

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How Routing Behaves Within the Adaptive Security Appliance

algorithms send small updates everywhere, while distance vector algorithms send larger updates only to neighboring routers. Distance vector algorithms know only about their neighbors. Typically, this type of algorithm is used in conjunction with OSPF routing protocols.

How Routing Behaves Within the Adaptive Security Appliance

The adaptive security appliance uses both routing table and XLATE tables for routing decisions. To handle destination IP translated traffic, that is, untranslated traffic, the adaptive security appliance searches for existing XLATE, or static translation to select the egress interface.

Egress Interface Selection Process

The selection process is as follows:

1.

If destination IP translating XLATE already exists, the egress interface for the packet is determined from the XLATE table, but not from the routing table.

2.

3.

If destination IP translating XLATE does not exist, but a matching static translation exists, then the egress interface is determined from the static route and an XLATE is created, and the routing table is not used.

If destination IP translating XLATE does not exist and no matching static translation exists, the packet is not destination IP translated. The adaptive security appliance processes this packet by looking up the route to select egress interface, then source IP translation is performed (if necessary).

For regular dynamic outbound NAT, initial outgoing packets are routed using the route table and then creating the XLATE. Incoming return packets are forwarded using existing XLATE only. For static NAT, destination translated incoming packets are always forwarded using existing XLATE or static translation rules.

Next Hop Selection Process

After selecting egress interface using any method described above, an additional route lookup is performed to find out suitable next hop(s) that belong to previously selected egress interface. If there are no routes in routing table that explicitly belong to selected interface, the packet is dropped with the level

6 error message 110001 (no route to host), even if there is another route for a given destination network that belongs to different egress interface. If the route that belongs to selected egress interface is found, the packet is forwarded to corresponding next hop.

Load sharing on the adaptive security appliance is possible only for multiple next-hops available using single egress interface. Load sharing cannot share multiple egress interfaces.

If dynamic routing is in use on adaptive security appliance and route table changes after XLATE creation, for example route flap, then destination translated traffic is still forwarded using old XLATE, not via route table, until XLATE times out. It may be either forwarded to wrong interface or dropped with message 110001 (no route to host), if old route was removed from the old interface and attached to another one by routing process.

The same problem may happen when there is no route flaps on the adaptive security appliance itself, but some routing process is flapping around it, sending source translated packets that belong to the same flow through the adaptive security appliance using different interfaces. Destination translated return packets may be forwarded back using the wrong egress interface.

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Supported Internet Protocols for Routing

This issue has a high probability in same security traffic configuration, where virtually any traffic may be either source-translated or destination-translated, depending on direction of initial packet in the flow.

When this issue occurs after a route flap, it can be resolved manually by using the

clear xlate

command, or automatically resolved by an XLATE timeout. XLATE timeout may be decreased if necessary. To ensure that this rarely happens, make sure that there is no route flaps on adaptive security appliance and around it. That is, ensure that destination translated packets that belong to the same flow are always forwarded the same way through the adaptive security appliance.

Supported Internet Protocols for Routing

The adaptive security appliance supports several internet protocols for routing. Each protocol is briefly described in this section.

•

Enhanced Interior Gateway Routing Protocol (EIGRP)

EIGRP provides compatibility and seamless interoperation with IGRP routers. An automatic-redistribution mechanism allows IGRP routes to be imported into Enhanced IGRP, and vice versa, so it is possible to add Enhanced IGRP gradually into an existing IGRP network.

•

For more information about configuring EIGRP, see the

“Configuring EIGRP” section on page 23-3 .

Open Shortest Path First (OSPF)

Open Shortest Path First (OSPF) is a routing protocol developed for Internet Protocol (IP) networks by the interior gateway protocol (IGP) working group of the Internet Engineering Task Force

(IETF). OSPF uses a link-state algorithm to build and calculate the shortest path to all known destinations. Each router in an OSPF area includes an identical link-state database, which is a list of each of the router usable interfaces and reachable neighbors.

For more information about configuring OSPF, see the

“Configuring OSPF” section on page 21-3 .

•

Routing Information Protocol

The Routing Information Protocol (RIP) is a distance-vector protocol that uses hop count as its metric. RIP is widely used for routing traffic in the global Internet and is an interior gateway protocol (IGP), which means that it performs routing within a single autonomous system.

For more information about configuring RIP, see the

“Configuring RIP” section on page 22-3 .

Information About the Routing Table


•

Displaying the Routing Table, page 18-5

•

•

How the Routing Table Is Populated, page 18-6

How Forwarding Decisions are Made, page 18-7

Displaying the Routing Table

To show all routes in ASDM that are in the routing table, choose

Monitoring > Routing > Routes

.

In this table, each row represents one route.

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How the Routing Table Is Populated

The adaptive security appliance routing table can be populated by statically defined routes, directly connected routes, and routes discovered by the RIP, EIGRP, and OSPF routing protocols. Because the adaptive security appliance can run multiple routing protocols in addition to having static and connected routes in the routing table, it is possible that the same route is discovered or entered in more than one manner. When two routes to the same destination are put into the routing table, the one that remains in the routing table is determined as follows:

•

If the two routes have different network prefix lengths (network masks), then both routes are considered unique and are entered in to the routing table. The packet forwarding logic then determines which of the two to use.

For example, if the RIP and OSPF processes discovered the following routes:

–

RIP: 192.168.32.0/24

–

OSPF: 192.168.32.0/19

Even though OSPF routes have the better administrative distance, both routes are installed in the routing table because each of these routes has a different prefix length (subnet mask). They are considered different destinations and the packet forwarding logic determine which route to use.

•

•

If the adaptive security appliance learns about multiple paths to the same destination from a single routing protocol, such as RIP, the route with the better metric (as determined by the routing protocol) is entered into the routing table.

Metrics are values associated with specific routes, ranking them from most preferred to least preferred. The parameters used to determine the metrics differ for different routing protocols. The path with the lowest metric is selected as the optimal path and installed in the routing table. If there are multiple paths to the same destination with equal metrics, load balancing is done on these equal cost paths.

If the adaptive security appliance learns about a destination from more than one routing protocol, the administrative distances of the routes are compared and the routes with lower administrative distance are entered into the routing table.

You can change the administrative distances for routes discovered by or redistributed into a routing protocol. If two routes from two different routing protocols have the same administrative distance, then the route with the lower

default

administrative distance is entered into the routing table. In the case of EIGRP and OSPF routes, if the EIGRP route and the OSPF route have the same administrative distance, then the EIGRP route is chosen by default.

Administrative distance is a route parameter that the adaptive security appliance uses to select the best path when there are two or more different routes to the same destination from two different routing protocols. Because the routing protocols have metrics based on algorithms that are different from the other protocols, it is not always possible to determine the “best path” for two routes to the same destination that were generated by different routing protocols.

Each routing protocol is prioritized using an administrative distance value. Table 18-1 shows the default

administrative distance values for the routing protocols supported by the adaptive security appliance.

Table 18-1 Default Administrative Distance for Supported Routing Protocols

Route Source

Connected interface

Static route

EIGRP Summary Route

Default Administrative Distance

0

1

5

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Table 18-1 Default Administrative Distance for Supported Routing Protocols

Internal EIGRP

OSPF

RIP

EIGRP external route

Unknown

90

110

120

170

255

The smaller the administrative distance value, the more preference is given to the protocol. For example, if the adaptive security appliance receives a route to a certain network from both an OSPF routing process (default administrative distance - 110) and a RIP routing process (default administrative distance

- 120), the adaptive security appliance chooses the OSPF route because OSPF has a higher preference.

This means the router adds the OSPF version of the route to the routing table.

In this example, if the source of the OSPF-derived route was lost (for example, due to a power shutdown), the adaptive security appliance would then use the RIP-derived route until the OSPF-derived route reappears.

The administrative distance is a local setting. For example, if you use the

distance-ospf

command to change the administrative distance of routes obtained through OSPF, that change would only affect the routing table for the adaptive security appliance the command was entered on. The administrative distance is not advertised in routing updates.

Administrative distance does not affect the routing process. The OSPF and RIP routing processes only advertise the routes that have been discovered by the routing process or redistributed into the routing process. For example, the RIP routing process advertises RIP routes, even if routes discovered by the

OSPF routing process are used in the adaptive security appliance routing table.

Backup Routes

A backup route is registered when the initial attempt to install the route in the routing table fails because another route was installed instead. If the route that was installed in the routing table fails, the routing table maintenance process calls each routing protocol process that has registered a backup route and requests them to reinstall the route in the routing table. If there are multiple protocols with registered backup routes for the failed route, the preferred route is chosen based on administrative distance.

Because of this process, you can create “floating” static routes that are installed in the routing table when the route discovered by a dynamic routing protocol fails. A floating static route is simply a static route configured with a greater administrative distance than the dynamic routing protocols running on the adaptive security appliance. When the corresponding route discover by a dynamic routing process fails, the static route is installed in the routing table.

How Forwarding Decisions are Made

Forwarding decisions are made as follows:

•

If the destination does not match an entry in the routing table, the packet is forwarded through the interface specified for the default route. If a default route has not been configured, the packet is discarded.

•

If the destination matches a single entry in the routing table, the packet is forwarded through the interface associated with that route.

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Information About IPv6 Support

•

If the destination matches more than one entry in the routing table, and the entries all have the same network prefix length, the packets for that destination are distributed among the interfaces associated with that route.

•

If the destination matches more than one entry in the routing table, and the entries have different network prefix lengths, then the packet is forwarded out of the interface associated with the route that has the longer network prefix length.

For example, a packet destined for 192.168.32.1 arrives on an interface of an adaptive security appliance with the following routes in the routing table: hostname#

show route

....

R 192.168.32.0/24 [120/4] via 10.1.1.2

O 192.168.32.0/19 [110/229840] via 10.1.1.3

....

In this case, a packet destined to 192.168.32.1 is directed toward 10.1.1.2, because 192.168.32.1 falls within the 192.168.32.0/24 network. It also falls within the other route in the routing table, but the

192.168.32.0/24 has the longest prefix within the routing table (24 bits verses 19 bits). Longer prefixes are always preferred over shorter ones when forwarding a packet.

Dynamic Routing and Failover

Because static routing systems cannot react to network changes, they generally are considered unsuitable for today's large, constantly changing networks. Most of the dominant routing algorithms today are dynamic routing algorithms, which adjust to changing network circumstances by analyzing incoming routing update messages. If the message indicates that a network change has occurred, the routing software recalculates routes and sends out new routing update messages. These messages permeate the network, stimulating routers to rerun their algorithms and change their routing tables accordingly.

Dynamic routing algorithms can be supplemented with static routes where appropriate. A router of last resort (a router to which all unroutable packets are sent), for example, can be designated to act as a repository for all unroutable packets, ensuring that all messages are at least handled in some way.

Dynamic routes are not replicated to the standby unit or failover group in a failover configuration.

Therefore, immediately after a failover occurs, some packets received by the adaptive security appliance may be dropped because of a lack of routing information or routed to a default static route while the routing table is repopulated by the configured dynamic routing protocols.

For more information about static routes and how to configure them, see the

“Configuring Static and

Default Routes” section on page 19-1

.


Many, but not all, features on the adaptive security appliance supports IPv6 traffic. This section describes the commands and features that support IPv6, and includes the following topics:

•

Features that Support IPv6, page 18-9

•

•

IPv6-Enabled Commands, page 18-9

Entering IPv6 Addresses in Commands, page 18-10

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Features that Support IPv6

The following features support IPv6:

Note

For features that use the Modular Policy Framework, be sure to use the

match any

command to match

IPv6 traffic; other

match

commands do not support IPv6.

•

•

•

•

•

•

•

•

•

The following application inspections support IPv6 traffic:

–

FTP

–

–

–

HTTP

ICMP

SIP

–

–

SMTP

IPSec-pass-thru

IPS

NetFlow Secure Event Logging filtering

Connection limits, timeouts, and TCP randomization

TCP Normalization

TCP state bypass

Access group, using an IPv6 access list

Static Routes

VPN (all types)

Note

Failover does not support IPv6. The

ipv6 address

command does not support setting standby addresses for failover configurations. The

failover interface ip

command does not support using IPv6 addresses on the failover and Stateful Failover interfaces.

IPv6-Enabled Commands

The following adaptive security appliance commands can accept and display IPv6 addresses:

• capture

•

•

•

• configure copy http

•

• name object-group ping

•

• show conn show local-host

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•

• show tcpstat ssh telnet

•

•

• tftp-server who

• write

The following commands were modified to work for IPv6:

•

•

•

•

• debug fragment ip verify mtu icmp

(entered as

ipv6 icmp

)

IPv6 Command Guidelines in Transparent Firewall Mode

The

ipv6 address

and

ipv6 enable

commands are available in global configuration mode instead of interface configuration mode. The

ipv6 address

command does not support the

eui

keyword. (The

ipv6 address link-local

command is still available in interface configuration mode.

The following IPv6 commands are not supported in transparent firewall mode, because they require router capabilities:

• ipv6 address autoconfig

•

•

•

• ipv6 nd prefix ipv6 nd ra-interval ipv6 nd ra-lifetime ipv6 nd suppress-ra

The

ipv6 local pool

VPN command is not supported, because transparent mode does not support VPN.

Entering IPv6 Addresses in Commands

When entering IPv6 addresses in commands that support them, simply enter the IPv6 address using standard IPv6 notation, for example:

ping fe80::2e0:b6ff:fe01:3b7a

.

The adaptive security appliance correctly recognizes and processes the IPv6 address. However, you must enclose the IPv6 address in square brackets ([ ]) in the following situations:

•

You need to specify a port number with the address, for example:

[fe80::2e0:b6ff:fe01:3b7a]:8080

.

•

The command uses a colon as a separator, such as the

write net

command and

config net

command, for example:

configure net [fe80::2e0:b6ff:fe01:3b7a]:/tftp/config/asaconfig

.

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Disabling Proxy ARPs


When a host sends IP traffic to another device on the same Ethernet network, the host needs to know the

MAC address of the device. ARP is a Layer 2 protocol that resolves an IP address to a MAC address. A host sends an ARP request asking “Who is this IP address?” The device owning the IP address replies,

“I own that IP address; here is my MAC address.”

Proxy ARP is used when a device responds to an ARP request with its own MAC address, even though the device does not own the IP address. The adaptive security appliance uses proxy ARP when you configure NAT and specify a mapped address that is on the same network as the adaptive security appliance interface. The only way traffic can reach the hosts is if the adaptive security appliance uses proxy ARP to claim that the adaptive security appliance MAC address is assigned to destination mapped addresses.

In rare circumstances, you might want to disable proxy ARP for NAT addresses.

If you have a VPN client address pool that overlaps with an existing network, the adaptive security appliance by default sends proxy ARPs on all interfaces. If you have another interface that is on the same

Layer 2 domain, it will see the ARP requests and will answer with the MAC address of its interface. The result of this is that the return traffic of the VPN clients towards the internal hosts will go to the wrong interface and will get dropped. In this case, you need to disable proxy ARPs for the interface where you do not want proxy ARPs.

To disable proxy ARPs, go to the Configuration > Device Setup > Routing > Proxy ARPs pane.

Fields

•

Interface—Lists the interface names.

•

Proxy ARP Enabled—Shows whether proxy ARP is enabled or disabled for NAT global addresses,

Yes or No.

•

•

Enable—Enables proxy ARP for the selected interface. By default, proxy ARP is enabled for all interfaces.

Disable—Disables proxy ARP for the selected interface.

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C H A P T E R

19


This chapter describes how to configure static and default routes on the adaptive security appliance and includes the following sections:

•

Information About Static and Default Routes, page 19-1

•

•

•

•

•

•

Licensing Requirements for Static and Default Routes, page 19-2


Configuring Static and Default Routes, page 19-2

Monitoring a Static or Default Route, page 19-8

Configuration Examples for Static or Default Routes, page 19-9

Feature History for Static and Default Routes, page 19-9

Information About Static and Default Routes

To route traffic to a non-connected host or network, you must define a static route to the host or network or, at a minimum, a default route for any networks to which the adaptive security appliance is not directly connected; for example, when there is a router between a network and the adaptive security appliance.

Without a static or default route defined, traffic to non-connected hosts or networks generates the following syslog message:

%ASA-6-110001: No route to

dest_address

from

source_address

Multiple context mode does not support dynamic routing,

You might want to use static routes in single context mode in the following cases:

•

Your networks use a different router discovery protocol from EIGRP, RIP, or OSPF.

•

•

Your network is small and you can easily manage static routes.

You do not want the traffic or CPU overhead associated with routing protocols.

The simplest option is to configure a default route to send all traffic to an upstream router, relying on the router to route the traffic for you. However, in some cases the default gateway might not be able to reach the destination network, so you must also configure more specific static routes. For example, if the default gateway is outside, then the default route cannot direct traffic to any inside networks that are not directly connected to the adaptive security appliance.

In transparent firewall mode, for traffic that originates on the adaptive security appliance and is destined for a non-directly connected network, you need to configure either a default route or static routes so the adaptive security appliance knows out of which interface to send traffic. Traffic that originates on the


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Chapter 19 Configuring Static and Default Routes

Licensing Requirements for Static and Default Routes

adaptive security appliance might include communications to a syslog server, Websense or N2H2 server, or AAA server. If you have servers that cannot all be reached through a single default route, then you must configure static routes. Additionally, the adaptive security appliance supports up to three equal cost routes on the same interface for load balancing.

Licensing Requirements for Static and Default Routes

Model

All models


Base License.







IPv6 Guidelines

Supports IPv6.


IPv6 static routes are not supported in transparent mode in ASDM.


This section explains how to configure a static, and a static default route and includes the following topics:

•

•

•

Configuring a Static Route, page 19-3

Configuring a Default Static Route, page 19-7

Configuring IPv6 Default and Static Routes, page 19-8

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Configuring a Static Route

Static routing algorithms are basically table mappings established by the network administrator before the beginning of routing. These mappings do not change unless the network administrator alters them.

Algorithms that use static routes are simple to design and work well in environments where network traffic is relatively predictable and where network design is relatively simple. Because of this fact, static routing systems cannot react to network changes.

Static routes remain in the routing table even if the specified gateway becomes unavailable. If the specified gateway becomes unavailable, you need to remove the static route from the routing table manually. However, static routes are removed from the routing table if the specified interface goes down, and are reinstated when the interface comes back up.

Note

If you create a static route with an administrative distance greater than the administrative distance of the routing protocol running on the adaptive security appliance, then a route to the specified destination discovered by the routing protocol takes precedence over the static route. The static route is used only if the dynamically discovered route is removed from the routing table.

To configure a static route, choose one of the following:

•

•

•

Add/Edit a Static Route, page 19-3

Configuring Static Route Tracking, page 19-6

Deleting Static Routes, page 19-6

Add/Edit a Static Route

To add or edit a static route in ASDM, perform the following steps:

Step 1

In the main ASDM window, choose

Configuration > Device Setup > Routing > Static Routes

.

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Step 2

•

•

•

Choose which route to filter by clicking one of the radio buttons:

Both

(filters both IPv4 and IPv6)

IPv4 only

IPv6 only


19-3



Step 3

Step 4

Step 5

Step 6

By default, the

Both

radio button is selected, and both IPv4 and IPv6 addresses appear in the pane. To limit your viewed choices to routes configured with IPv4 addresses, click the

IPv4

radio button. To limit your viewed choices to routes configured with IPv6 addresses, click the

IPv6

radio button.

Click

Add

or

Edit

.

The Add or Edit Static Route dialog box appears.

From the Interface drop-down list, choose the internal or external network interface name enabled in

Interfaces:

• management

(internal interface)

• outside

(external interface)

In the IP Address field, type an internal or external network IP address for the destination network.

For IPv4 addresses, enter

0.0.0.0

to specify a default route. The 0.0.0.0 IP address can be abbreviated as

0. Optionally, click the ellipsis to browse for an address.

For IPv6 addresses, enter two colons (

::

) to specify a default route. Optionally, click the ellipsis to browse for an address.

In the Gateway IP field, enter the IP address of the gateway router, which is the next hop address for this route.

To enter a default route, set the IP address and mask to 0.0.0.0, or the shortened form of 0.

Optionally, click the ellipsis to browse for an address.

Step 7

Step 8

Step 9

Note

If an IP address from one adaptive security appliance interface is used as the gateway IP address, the adaptive security appliance will ARP the designated IP address in the packet instead of

ARPing the gateway IP address.

The addresses you specify for the static route are the addresses that are in the packet before entering the adaptive security appliance and performing NAT.

Choose the netmask from the drop-down list for the destination network.

Depending upon which route you chose to filter (IPv4, IPv6, or both), do one of the following:

•

For IPv4 static routes (or for both IPv4 and IPv6 static routes), enter the network mask address that applies to the IP address. Enter

0.0.0.0

to specify a default route. The

0.0.0.0

netmask can be abbreviated as

0

.

•

For IPv6 static routes only, enter a prefix length.

In the Metric field, type the metric, or administrative distance.

The metric or distance is the administrative distance for the route. The default is 1 if you do not specify a value. Administrative distance is a parameter used to compare routes among different routing protocols. The default administrative distance for static routes is 1, giving it precedence over routes discovered by dynamic routing protocols but not directly connect ed routes.

The default administrative distance for routes discovered by OSPF is 110. If a static route has the same administrative distance as a dynamic route, the static routes take precedence. Connected routes always take precedence over static or dynamically discovered routes.

(Optional) In the Options area, choose only one of the following options for a static route.

•

None—No options are specified for the static route. This option is the default.

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•

•

Tunneled—This option specifies the route as the default tunnel gateway for VPN traffic. This option is used for the default route only. You can configure only one tunneled route per device. The tunneled option is not supported under transparent mode.

Tracked—This option specifies that the route is tracked. The tracking object ID and the address of the tracking target also appear. The tracked option is supported in single, routed mode only.

–

Track ID—Enter a unique identifier for the route tracking process.

–

–

Track IP Address/DNS Name—Enter the IP address or hostname of the target being tracked.

Typically, this would be the IP address of the next hop gateway for the route, but it could be any network object available off of that interface.

SLA ID—Enter a unique identifier for the SLA monitoring process.

Note

The Tracked option is not supported for IPv6.

Step 10

(Optional) Choose

Monitoring Options

.

The Route Monitoring Options dialog box appears. From here you change the following tracking object monitoring properties:

•

Frequency—Allows you to modify how often, in seconds, the adaptive security appliance should test for the presence of the tracking target. Valid values are from 1 to 604800 seconds. The default value is 60 seconds.

•

•

•

Threshold—Allows you to enter the amount of time, in milliseconds, that indicates an over-threshold event. This value cannot be more than the timeout value.

Timeout—Allows you to modify the amount of time, in milliseconds, that the route monitoring operation should wait for a response from the request packets. Valid values are from 0 to 604800000 milliseconds. The default value is 5000 milliseconds.

Data Size—Allows you to modify the size of data payload to use in the echo request packets. The default value is 28. Valid values range from 0 to 16384.

Note

This setting specifies the size of the payload only; it does not specify the size of the entire packet.

Step 11

Step 12

•

ToS—Allows you to choose a value for the type of service byte in the IP header of the echo request.

Valid values are from 0 to 255. The default value is 0.

•

Number of Packets—Allows you to choose the number of echo requests to send for each test. Valid values are from 1 to 100. The default value is 1.

Click

OK

.

Click

Apply


The added or edited route information appears in the Static Routes pane. The monitoring process begins as soon as you save the newly configured route.

OL-20339-01


19-5



Configuring Static Route Tracking

To configure tracking for a static route, perform the following steps:

Note

Static route tracking is available for IPv4 routes only.

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Choose a target of interest. Make sure the target responds to echo requests.

Open the Static Routes page by choosing

Configuration > Routing > Static Routes

.

Click

Add

to configure a static route that is to be used based on the availability of your selected target of interest. You must enter the Interface, IP Address, Mask, Gateway, and Metric for this route.

Click the

Tracked

radio button in the Options area for this route.

Configure the tracking properties. You must enter a unique Track ID, a unique SLA ID, and the IP address of your target of interest.

(Optional) To configure the monitoring properties, click

Monitoring Options

in the Add Static Route dialog box.

Click

OK

to save your changes.

The monitoring process begins as soon as you save the tracked route.

Create a secondary route by repeating Steps 1 through 7.

The secondary route is a static route to the same destination as the tracked route, but through a different interface or gateway. You must assign this route a higher administrative distance (metric) than your tracked route.

Click

OK


Deleting Static Routes

To delete a static route, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Choose

Configuration

>

Device Setup

>

Routing

>

Static Routes

.

On the Static Routes pane, choose which route to delete.

By default, the

Both

radio button is checked, and both IPv4 and IPv6 addresses appear in the pane.

•

To limit your viewed choices to routes configured with IPv4 addresses, click the

IPv4

radio button.

•

To limit your viewed choices to routes configured with IPv6 addresses, click the

IPv6

radio button.

Click

Delete

.

The deleted route is removed from list of routes on in the main Static Routes pane.

Click

Apply


19-6


OL-20339-01



Configuring a Default Static Route

A default route identifies the gateway IP address to which the adaptive security appliance sends all IP packets for which it does not have a learned or static route. A default static route is simply a static route with 0.0.0.0/0 as the destination IP address. Routes that identify a specific destination take precedence over the default route.

Note

In ASA software Versions 7.0 and later, if you have two default routes configured on different interfaces that have different metrics, the connection to the ASA firewall that is made from the higher metric interface fails, but connections to the ASA firewall from the lower metric interface succeed as expected.

You can define up to three equal cost default route entries per device. Defining more than one equal cost default route entry causes the traffic sent to the default route to be distributed among the specified gateways. When defining more than one default route, you must specify the same interface for each entry.

If you attempt to define more than three equal cost default routes, or if you attempt to define a default route with a different interface than a previously defined default route, you receive the following message:

“ERROR: Cannot add route entry, possible conflict with existing routes.”

You can define a separate default route for tunneled traffic along with the standard default route. When you create a default route with the

tunneled

option, all traffic from a tunnel terminating on the adaptive security appliance that cannot be routed using learned or static routes, is sent to this route. For traffic emerging from a tunnel, this route overrides over any other configured or learned default routes.

Limitations on Configuring a Default Static Route

The following restrictions apply to default routes with the tunneled option:

•

•

Do not enable unicast RPF (

ip verify reverse-path

) on the egress interface of tunneled route.

Enabling Unicast RPF on the egress interface of a tunneled route causes the session to fail.

Do not enable TCP intercept on the egress interface of the tunneled route. Doing so causes the session to fail.

•

Do not use the VoIP inspection engines (CTIQBE, H.323, GTP, MGCP, RTSP, SIP, SKINNY), the

DNS inspect engine, or the DCE RPC inspection engine with tunneled routes. These inspection engines ignore the tunneled route.

You cannot define more than one default route with the tunneled option; ECMP for tunneled traffic is not supported.

To add or edit a tunneled default static route in ASDM, perform the following steps:

Step 1

Step 2

Step 3

Step 4

On the main ASDM window, choose


.

Click

Add

or

Edit

.

In the Options area, choose

Tunneled

.

Click

OK

.

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19-7


Monitoring a Static or Default Route

Configuring IPv6 Default and Static Routes

The adaptive security appliance automatically routes IPv6 traffic between directly connected hosts if the interfaces to which the hosts are attached are enabled for IPv6 and the IPv6 ACLs allow the traffic.

To add or edit a default static route in ASDM, perform the following steps:

Step 1

Step 2

Step 3

Step 4



.

Click the

IPv6 only

radio button.

Click

Add

or

Edit

.

Click

OK

.

Monitoring a Static or Default Route

One of the problems with static routes is that there is no inherent mechanism for determining if the route is up or down. They remain in the routing table even if the next hop gateway becomes unavailable. Static routes are only removed from the routing table if the associated interface on the adaptive security appliance goes down.

The static route tracking feature provides a method for tracking the availability of a static route and installing a backup route if the primary route should fail. This allows you to, for example, define a default route to an ISP gateway and a backup default route to a secondary ISP in case the primary ISP becomes unavailable.

The adaptive security appliance does this by associating a static route with a monitoring target that you define. It monitors the target using ICMP echo requests. If an echo reply is not received within a specified time period, the object is considered down and the associated route is removed from the routing table. A previously configured backup route is used in place of the removed route.

When selecting a monitoring target, you need to make sure it can respond to ICMP echo requests. The target can be any network object that you choose, but you should consider using the following:

•

•

•

•

The ISP gateway (for dual ISP support) address

The next hop gateway address (if you are concerned about the availability of the gateway)

A server on the target network, such as a AAA server, that the adaptive security appliance needs to communicate with

A persistent network object on the destination network (a desktop or notebook computer that may be shut down at night is not a good choice)

You can configure static route tracking for statically defined routes or default routes obtained through

DHCP or PPPoE. You can only enable PPPoE clients on multiple interface with route tracking.

To monitor the state of a route in ASDM, in the main ASDM window, choose

Monitoring > Routing >

Routes

.

In this table, each row represents one route.

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Configuration Examples for Static or Default Routes

Configuration Examples for Static or Default Routes

The following example shows how to configure static routes:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Step 12



.

Choose

Management

from the Interfaces drop-down list.

Enter

10.1.1.0

in the IP Address field.

Choose

255.255.255.0

from the Mask drop-down list.

Enter

10.1.2.45 1

in the Gateway IP field.

In this step, a static route is created that sends all traffic destined for 10.1.1.0/24 to the router (10.1.2.45) connected to the inside interface.

Click

OK

.

Choose


.

Click

Add

.

Enter the IP Address in the IP Address field for the destination network.

In this case, the IP routes are: 192.168.1.1, 192.168.1.2, 192.168.1.3, and 192.168.1.4. When adding

192.168.1.4, click the

Tunneled

radio button in the Options area.

Enter the Gateway IP Address in the Gateway IP Address field for the address of the next-hop router.

The addresses you specify for the static route are the addresses that are in the packet before entering the adaptive security appliance and performing NAT.

Choose the netmask for the destination network from the NetMask drop-down list.

Click

OK

.

Feature History for Static and Default Routes

Table 19-1


Table 19-1 Feature History for Static and Default Routes

Feature Name

Routing

Platform

Releases

7.0(1)


The

route

command was introduced to enter a static or default route for the specified interface.

The

Configuration > Device Setup > Routing

screen was introduced.

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19-9

Feature History for Static and Default Routes


19-10


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C H A P T E R

20

Defining Route Maps

This chapter describes route maps and includes the following sections:

•

Route Maps Overview, page 20-1

•

•

•

•

•

•

Licensing Requirements for Route Maps, page 20-3


Defining a Route Map, page 20-4

Customizing a Route Map, page 20-5

Configuration Example for Route Maps, page 20-7

Feature History for Route Maps, page 20-7

Route Maps Overview

Route maps are used when redistributing routes into an OSPF, RIP, or EIGRP routing process. They are also used when generating a default route into an OSPF routing process. A route map defines which of the routes from the specified routing protocol are allowed to be redistributed into the target routing process.

Route maps have many features in common with widely known access control lists (ACLs). These are some of the traits common to both mechanisms:

•

They are an ordered sequence of individual statements, each has a permit or deny result. Evaluation of ACL or route maps consists of a list scan, in a predetermined order, and an evaluation of the criteria of each statement that matches. A list scan is aborted once the first statement match is found and an action associated with the statement match is performed.

•

They are generic mechanisms—criteria matches and match interpretation are dictated by the way they are applied. The same route map applied to different tasks might be interpreted differently.

These are some of the differences between route maps and ACLs:

•

•

Route maps frequently use ACLs as matching criteria.

The main result from the evaluation of an access list is a yes or no answer—an ACL either permits or denies input data. Applied to redistribution, an ACL determines if a particular route can (route matches ACLs permit statement) or can not (matches deny statement) be redistributed. Typical route maps not only permit (some) redistributed routes but also modify information associated with the route, when it is redistributed into another protocol.

•

Route maps are more flexible than ACLs and can verify routes based on criteria which ACLs can not verify. For example, a route map can verify if the type of route is internal.


OL-20339-01 20-1

Chapter 20 Defining Route Maps

Route Maps Overview

•

Each ACL ends with an implicit deny statement, by design convention; there is no similar convention for route maps. If the end of a route map is reached during matching attempts, the result depends on the specific application of the route map. Fortunately, route maps that are applied to redistribution behave the same way as ACLs: if the route does not match any clause in a route map then the route redistribution is denied, as if the route map contained deny statement at the end.

The dynamic protocol

redistribute

command allows you to apply a route map. In ASDM, this capability for redistribution can be found when you add or edit a new route map (see the

“Defining a Route Map” section on page 20-4 ). Route maps are preferred if you intend to either modify route information during

redistribution or if you need more powerful matching capability than an ACL can provide. If you simply need to selectively permit some routes based on their prefix or mask, we recommends that you use route map to map to an ACL (or equivalent prefix list) directly in the

redistribute

command. If you use a route map to selectively permit some routes based on their prefix or mask, you typically use more configuration commands to achieve the same goal.

We recommend that you number clauses in intervals of 10, to reserve numbering space in case you need to insert clauses in the future.


•

Permit and Deny Clauses

•

Match and Set Clause Values

Permit and Deny Clauses

Route maps can have

permit

and

deny

clauses. In

route-map ospf-to-eigrp

, there is one deny clause

(with sequence number 10) and two permit clauses. The deny clause rejects route matches from redistribution. Therefore, the following rules apply:

•

•

If you use an ACL in a route map using a permit clause, routes that are permitted by the ACL are redistributed.

If you use an ACL in a route map deny clause, routes that are permitted by the ACL are not redistributed.

•

If you use an ACL in a route map permit or deny clause, and the ACL denies a route, then the route map clause match is not found and the next route-map clause is evaluated.

Match and Set Clause Values

Each route map clause has two types of values:

•

•

match

—

Selects routes to which this clause should be applied.

set

—

Modifies information which will be redistributed into the target protocol.

For each route that is being redistributed, the router first evaluates the match criteria of a clause in the route map. If the match criteria succeed, then the route is redistributed or rejected as dictated by the permit or deny clause, and some of its attributes might be modified by the values set from the Set Value tab in ASDM or from the

set

commands. If the match criteria fail, then this clause is not applicable to the route, and the software proceeds to evaluate the route against the next clause in the route map.

Scanning of the route map continues until a clause is found whose

match

command(s), or Match Clause as set from the Match Clause tab in ASDM, match the route or until the end of the route map is reached.

A

match

or

set

value in each clause can be missed or repeated several times, if one of these conditions exists:

20-2


OL-20339-01


Licensing Requirements for Route Maps

•

•

•

•

If several

match

commands or Match Clause values in ASDM are present in a clause, all must succeed for a given route in order for that route to match the clause (in other words, the logical AND algorithm is applied for multiple match commands).

If a

match

command or Match Clause value in ASDM refers to several objects in one command, either of them should match (the logical OR algorithm is applied). For example, in the

match ip address 101 121

command, a route is permitted if access list 101 or access list 121 permits it.

If a

match

command or Match Clause value in ASDM is not present, all routes match the clause. In the previous example, all routes that reach clause 30 match; therefore, the end of the route map is never reached.

If a

set

command, or Set Value in ASDM, is not present in a route map permit clause, then the route is redistributed without modification of its current attributes.

Note

Do not configure a

set

command in a route map deny clause because the deny clause prohibits route redistribution—there is no information to modify.

A route map clause without a

match

or

set

command, or Match or Set Value as set on the Match or Set

Value tab in ASDM, performs an action. An empty permit clause allows a redistribution of the remaining routes without modification. An empty deny clause does not allows a redistribution of other routes (this is the default action if a route map is completely scanned but no explicit match is found).

Licensing Requirements for Route Maps

Model

All models


Base License.




Supported in single context mode.


Supported only in routed mode. Transparent mode is not supported.

IPv6 Guidelines

Does not support IPv6.

OL-20339-01


20-3


Defining a Route Map

Defining a Route Map

When defining which of the routes from the specified routing protocol are allowed to be redistributed into the target routing process, you must define a route map. This involves adding, editing, or deleting a route map.

Add/Edit a Route Map

In ASDM, you can define a route map by adding, editing, or deleting a route map name, sequence number, or redistribution.

To add, edit, or delete a route map, perform the following steps:

Step 1

Step 2

Step 3

In ASDM, choose

Configuration > Device Setup > Routing > Route Maps

.

Click

Add

.

The Add Route Map or Edit Route Map dialog box appears.

Enter the route map name and sequence number. The route map name is the name that you are giving a particular route. The sequence number is the order in which you add or delete the route map entries into the adaptive security appliance.

Note

If you are editing an existing route map, the fields for Route Map name and sequence number are already filled in.

Step 4

Step 5

To reject route matches from redistribution, click

Deny

. If you use an ACL in a route-map Deny clause, routes that are permitted by the ACL are not redistributed. To allow route matches for redistribution. click

Permit

. If you use an ACL in a route-map Permit clause, routes that are permitted by the ACL are redistributed.

In addition, if you use an ACL in a route-map Permit or Deny clause, and the ACL denies a route, then the route-map clause match is not found and the next route-map clause is evaluated.

Click the

Match Clause

tab to choose routes to which this clause should be applied, and set the following parameters:

•

Check the

Interface

check box to enable or disable matching the first hop interface of a route or to match any routes with the specified next hop interface. If you specify more than one interface, then the route can match either interface.

–

Enter the interface name in the Interface field, or click the ellipses to display the Browse

Interface dialog box.

•

–

Choose the interface type (

inside

or

outside

), click

Selected Interface

, and then click

OK

.

Check the

IP

check box to enable or disable matching of the IP address, Next Hop, or Route Source,

This feature allows you to match any routes that have a destination network that matches a standard

ACL. If you specify more than one ACL, then the route can match any of the ACLs. Additionally, you can match any routes that have been advertised by routers that match a standard ACL. If you specify more than one ACL, then the route can match any of the ACLs. When enabled, you can choose more than one item from the list.

–

–

Choose

Match IP Address

to enable or disable the Match address of a route or match packet.

Choose

Match Next Hop

to enable or disable the Match next hop address of a route.

20-4


OL-20339-01


Customizing a Route Map

Step 6

–

–

–

Choose

Match Route Source

to enable or disable the Match advertising source address of route.

Click the ellipses to display the Browse Access List dialog box.

Choose the ACL that you want, and click

Selected Access List

, then click

OK

.

•

Check the

Metric Value

check box to enable or disable matching the metric of a route.

–

In the Metric Value field, type the metric values. You can enter multiple values, separated by commas. This value allows you to match any routes that have a specified metric. The metric value can range from 0 to 4294967295.

•

Check the

Route Type

check box to enable or disable matching of the route type. Valid route types are: External1, External2, Internal, Local, NSSA-External1, and NSSA-External2. When enabled, you can select more than one choice from the list.

Click the

Set Clause

tab to modify the following information, which will be redistributed to the target protocol:

–

–

Select the

Set Metric Clause

check box to enable or disable the metric value for the destination routing protocol, and type the value in the Value field.

Select the

Set Metric Type

check box to enable or disable the type of metric for the destination routing protocol, and choose the metric type from the drop-down list.


This section describes how to customize the route map and includes the following topics:

•

•

Defining a Route to Match a Specific Destination Address, page 20-5

Configuring the Metric Values for a Route Action, page 20-6

Defining a Route to Match a Specific Destination Address

To define a route to match a specified destination address, perform the following steps:

Step 1

Step 2

Step 3

In ASDM, choose


.

Click

Add

.

The Add or Edit Route Map dialog box appears. From this dialog box you can assign or select the route map name, the sequence number and its redistribution access (that is, permit or deny). Route map entries are read in order. You can identify the order using the sequence number, or the adaptive security appliance uses the order in which you add the entries.

Click the

Match Clause

tab to choose routes to which this clause should be applied, and set the following parameters:

•

Check the

Interface

check box to enable or disable matching the first hop interface of a route or to match any routes with the specified next hop interface. If you specify more than one interface, then the route can match either interface.

–

Enter the interface name in the Interface field, or click the ellipses to display the Browse

Interface dialog box.

OL-20339-01


20-5



•

•

•

–

Choose the interface type (

inside

or

outside

), click

Selected Interface

, and then click

OK

.

Check the

IP

check box to enable or disable matching of the IP address, Next Hop, or Route Source,

This feature allows you to match any routes that have a destination network that matches a standard

ACL. If you specify more than one ACL, then the route can match any of the ACLs. Additionally, you can match any routes that have been advertised by routers that match a standard ACL. If you specify more than one ACL, then the route can match any of the ACLs. When enabled, you can choose more than one item from the list.

–

Choose

Match IP Address

to enable or disable the Match address of a route or match packet.

–

–

Choose

Match Next Hop

to enable or disable the Match next hop address of a route.

Choose

Match Route Source

to enable or disable the Match advertising source address of route.

–

–

Click the ellipses to display the Browse Access List dialog box.

Choose the ACL that you want, and click

Selected Access List

, then click

OK

.

Check the

Metric Value

check box to enable or disable matching the metric of a route.

–

In the Metric Value field, type the metric values. You can enter multiple values, separated by commas. This value allows you to match any routes that have a specified metric. The metric value can range from 0 to 4294967295.

Check the

Route Type

check box to enable or disable matching of the route type. Valid route types are: External1, External2, Internal, Local, NSSA-External1, and NSSA-External2. When enabled, you can select more than one choice from the list.

Configuring the Metric Values for a Route Action

To configure the metric value for a route action, perform the following steps:

Step 1

Step 2

Step 3

In ASDM, choose


.

Click

Add

.

The Add or Edit Route Map dialog box appears. From this dialog box you can assign or select the route map name, the sequence number and its redistribution access, that is, permit or deny. Route map entries are read in order. You can identify the order using the sequence number, or the adaptive security appliance uses the order in which you add the entries.

Click the

Set Clause

tab to modify the following information, which will be redistributed to the target protocol:

•

Select the

Set Metric Clause

check box to enable or disable the metric value for the destination routing protocol, and type the value in the Value field.

•

Select the

Set Metric Type

check box to enable or disable the type of metric for the destination routing protocol, and choose the metric type from the drop-down list.

20-6


OL-20339-01


Configuration Example for Route Maps

Configuration Example for Route Maps

The following example shows how to redistribute routes with a hop count equal to 1 into OSPF.

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

In ASDM, choose


.

Click

Add

.

Enter

1-to-2

in the Route Map Name field.

Enter the routing sequence number in the

Sequence Number

field.

Click the

Permit

radio button

By default this tab is on top.

Click the

Match Clause

tab.

Check the

Match Metric of Route

check box and type a value of

1

for the metric value .

Click the

Set Clause

tab.

Check the

Set Metric Value

check box, and type a value of

5

for the metric value.

Check the

Set Metric-Type

check box, and choose

Type-1

.

Feature History for Route Maps

Table 20-1 lists each feature change and the platform release in which it was implemented. ASDM is backwards-compatible with multiple platform releases, so the specific ASDM release in which support was added is not listed.

Table 20-1 Feature History for Static and Default Routes

Feature Name

Route mapping

Platform

Releases

7.0(1)

Enhanced support for static and dynamic route maps.

8.0(2)


The

route-map

command allows you to define a route map entry.

The

Configuration > Device Setup > Routing > Route

Maps


Enhanced support for dynamic and static route maps was added.

OL-20339-01


20-7



20-8


OL-20339-01



OL-20339-01


20-9



20-10


OL-20339-01

C H A P T E R

21


This chapter describes how to configure the adaptive security appliance to route data, perform authentication, and redistribute routing information, using the Open Shortest Path First (OSPF) routing protocol.


•

•

•

•

•

Information About OSPF, page 21-1

Licensing Requirements for OSPF, page 21-3


Configuring OSPF, page 21-3

•

•

•

Customizing OSPF, page 21-4

Monitoring OSPF, page 21-20

Configuration Example for OSPF, page 21-19

Feature History for OSPF, page 21-21

Information About OSPF

OSPF is an interior gateway routing protocol that uses link states rather than distance vectors for path selection. OSPF propagates link-state advertisements rather than routing table updates. Because only

LSAs are exchanged instead of the entire routing tables, OSPF networks converge more quickly than RIP networks.

OSPF uses a link-state algorithm to build and calculate the shortest path to all known destinations. Each router in an OSPF area contains an identical link-state database, which is a list of each of the router usable interfaces and reachable neighbors.

The advantages of OSPF over RIP include the following:

•

•

OSPF link-state database updates are sent less frequently than RIP updates, and the link-state database is updated instantly rather than gradually as stale information is timed out.

Routing decisions are based on cost, which is an indication of the overhead required to send packets across a certain interface. The adaptive security appliance calculates the cost of an interface based on link bandwidth rather than the number of hops to the destination. The cost can be configured to specify preferred paths.

The disadvantage of shortest path first algorithms is that they require a lot of CPU cycles and memory.


21-1 OL-20339-01

Chapter 21 Configuring OSPF

Information About OSPF

The adaptive security appliance can run two processes of OSPF protocol simultaneously, on different sets of interfaces. You might want to run two processes if you have interfaces that use the same IP addresses (NAT allows these interfaces to coexist, but OSPF does not allow overlapping addresses). Or you might want to run one process on the inside, and another on the outside, and redistribute a subset of routes between the two processes. Similarly, you might need to segregate private addresses from public addresses.

You can redistribute routes into an OSPF routing process from another OSPF routing process, a RIP routing process, or from static and connected routes configured on OSPF-enabled interfaces.

The adaptive security appliance supports the following OSPF features:

•

•

•

•

•

Support of intra-area, interarea, and external (Type I and Type II) routes.

Support of a virtual link.

OSPF LSA flooding.

Authentication to OSPF packets (both password and MD5 authentication).

•

Support for configuring the adaptive security appliance as a designated router or a designated backup router. The adaptive security appliance also can be set up as an ABR.

Support for stub areas and not-so-stubby-areas.

Area boundary router Type-3 LSA filtering.

OSPF supports MD5 and clear text neighbor authentication. Authentication should be used with all routing protocols when possible because route redistribution between OSPF and other protocols (like

RIP) can potentially be used by attackers to subvert routing information.

If NAT is used, if OSPF is operating on public and private areas, and if address filtering is required, then you need to run two OSPF processes—one process for the public areas and one for the private areas.

A router that has interfaces in multiple areas is called an Area Border Router (ABR). A router that acts as a gateway to redistribute traffic between routers using OSPF and routers using other routing protocols is called an Autonomous System Boundary Router (ASBR).

An ABR uses LSAs to send information about available routes to other OSPF routers. Using ABR Type

3 LSA filtering, you can have separate private and public areas with the adaptive security appliance acting as an ABR. Type 3 LSAs (inter-area routes) can be filtered from one area to other. This lets you use NAT and OSPF together without advertising private networks.

Note

Only Type 3 LSAs can be filtered. If you configure the adaptive security appliance as an ASBR in a private network, it will send Type 5 LSAs describing private networks, which will get flooded to the entire AS including public areas.

If NAT is employed but OSPF is only running in public areas, then routes to public networks can be redistributed inside the private network, either as default or Type 5 AS External LSAs. However, you need to configure static routes for the private networks protected by the adaptive security appliance.

Also, you should not mix public and private networks on the same adaptive security appliance interface.

You can have two OSPF routing processes, one RIP routing process, and one EIGRP routing process running on the adaptive security appliance at the same time.

21-2


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Licensing Requirements for OSPF

Licensing Requirements for OSPF

Model

All models


Base License.






Supported in routed mode only. Transparent mode is not supported.

IPv6 Guidelines



This section describes how to enable an OSPF process on your system.

After you enable OSPF, you need to define a route map. For more information, see the

“Defining Route

Maps” section on page 20-1

. Then you generate a default route. For more information, see the

“Configuring Static and Default Routes” section on page 19-2 .

After you have defined a route map for the OSPF process, you can customize the OSPF process to suit your particular needs, To learn how to customize the OSPF process on your system, see the

“Customizing OSPF” section on page 21-4

.

To enable OSPF, you need to create an OSPF routing process, specify the range of IP addresses associated with the routing process, then assign area IDs associated with that range of IP addresses.

You can enable up to two OSPF process instances. Each OSPF process has its own associated areas and networks.

To enable OSPF, perform the following steps:

Step 1


Configuration > Device Setup > Routing > OSPF > Setup

.

In the OSPF Setup pane, you can enable OSPF processes, configure OSPF areas and networks, and define OSPF route summarization.

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21-3

Customizing OSPF


The three tabs in ASDM used to enable OSPF are as follows:

•

•

Process Instances tab—This tab allows you to enable up to two OSPF process instances. Once you check the

Enable Each OSPF Process

check box, you can enter a unique identifier numeric identifier for that OSPF process. This process ID is used internally and does not need to match the

OSPF process ID on any other OSPF devices; valid values are from 1 to 65535. Each OSPF process has its own associated areas and networks.

If you choose

Advanced

, you can configure the Router ID, Adjacency Changes, Administrative

Route Distances, Timers, and Default Information Originate settings for each OSPF process. See the

“Configuring Route Calculation Timers” section on page 21-15 for more information.

Area/Networks tab—This tab allows you to display the areas, and the networks they contain, for each OSPF process on the adaptive security appliance. From this tab you can display the area ID, the area type, the type of authentication set for the area. To add or edit the OSPF area or network, see the

“Configuring OSPF Area Parameters” section on page 21-12


•

Route Summarization tab—This tab allows you to configure an ABR. In OSPF, an ABR will advertise networks in one area into another area. If the network numbers in an area are assigned in a way such that they are contiguous, you can configure the ABR to advertise a summary route that covers all the individual networks within the area that fall into the specified range. See the

“Configuring Route Summarization Between OSPF Areas” section on page 21-8



This section explains how to customize the OSPF process and includes the following topics:

•

Redistributing Routes Into OSPF, page 21-5

21-4


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•

•

•

•

•

•

•

•

•

•

•

Configuring OSPF Interface Parameters, page 21-9

Configuring Route Summarization Between OSPF Areas, page 21-8

Configuring OSPF Interface Parameters, page 21-9

Configuring OSPF Area Parameters, page 21-12

Configuring OSPF NSSA, page 21-13

Configuring Route Calculation Timers, page 21-15

Defining Static OSPF Neighbors, page 21-14

Logging Neighbors Going Up or Down, page 21-16

Configuring Filtering in OSPF, page 21-16

Configuring a Virtual Link in OSPF, page 21-17

Restarting the OSPF Process, page 21-19


Redistributing Routes Into OSPF

The adaptive security appliance can control the redistribution of routes between OSPF routing processes.

Note

If you want to redistribute a route by defining which of the routes from the specified routing protocol are allowed to be redistributed into the target routing process, you must first generate a default route. See

the “Configuring Static and Default Routes” section on page 19-2

and then define a route map according to the

“Defining a Route Map” section on page 20-4

.

To redistribute static, connected, RIP, or OSPF routes into an OSPF process, perform the following steps:

Step 1

Step 2


Configuration > Device Setup > Routing > OSPF >

Redistribution

.

The Redistribution pane displays the rules for redistributing routes from one routing process into an

OSPF routing process. You can redistribute routes discovered by RIP and OSPF into the EIGRP routing process. You can also redistribute static and connected routes into the EIGRP routing process. You do not need to redistribute static or connected routes if they fall within the range of a network that has been configured through the Setup > Networks tab.

Choose

Add

or

Edit

.

Alternatively, double-clicking a table entry in the Redistribution pane (if any) opens the Add/Edit OSPF

Redistribution Entry dialog box for the selected entry.

Note

All steps that follow are optional.

Step 3

Step 4

The Add/Edit OSPF Redistribution Entry dialog box lets you add a new redistribution rule to or edit an existing redistribution rule in the Redistribution table. Some of the redistribution rule information cannot be changed when you are editing an existing redistribution rule.

Choose the OSPF process associated with the route redistribution entry. If you are editing an existing redistribution rule, you cannot change this setting.

Choose the source protocol from which the routes are being redistributed. You can choose one of the following options:


OL-20339-01 21-5



Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

•

•

•

•

•

Static—Redistribute static routes to the OSPF routing process.

Connected—Redistribute connected routes (routes established automatically by virtue of having IP enabled on the interface) to the OSPF routing process. Connected routes are redistributed as external to the AS.

OSPF—Redistribute routes from another OSPF routing process. Choose the OSPF process ID from the list. If you choose this protocol, the Match options on this dialog box become visible. These options are not available when redistributing static, connected, RIP, or EIGRP routes. Skip to Step 5.

RIP—Redistribute routes from the RIP routing process.

EIGRP—Redistribute routes from the EIGRP routing process. Choose the autonomous system number of the EIGRP routing process from the list.

If you have chosen OSPF for the source protocol, choose the conditions used for redistributing routes from another OSPF routing process into the selected OSPF routing process. These options are not available when redistributing static, connected, RIP, or EIGRP routes. The routes must match the selected condition to be redistributed. You can choose one or more of the following match conditions:

•

Internal—The route is internal to a specific AS.

•

•

•

•

External 1—Routes that are external to the autonomous system, but are imported into OSPF as Type

1 external routes.

External 2—Routes that are external to the autonomous system, but are imported into OSPF as Type

2 external routes.

NSSA External 1—Routes that are external to the autonomous system, but are imported into OSPF as Type 2 NSSA routes.

NSSA External 2—Routes that are external to the autonomous system, but are imported into OSPF as Type 2 NSSA routes.

In the Metric Value field, enter the metric value for the routes being redistributed. Valid values range from 1 to 16777214.

When redistributing from one OSPF process to another OSPF process on the same device, the metric will be carried through from one process to the other if no metric value is specified. When redistributing other processes to an OSPF process, the default metric is 20 when no metric value is specified.

Choose the

Metric Type

.

Choose “

1

” if the metric is a Type 1 external route, or “

2

” if the metric is a Type 2 external route.

Enter the tag value in the Tag Value field.

The tag value is a 32-bit decimal value attached to each external route that is not used by OSPF itself, but may be used to communicate information between ASBRs. Valid values range from 0 to

4294967295.

Check the

Use Subnets

check box to enable the redistribution of subnetted routes. Uncheck this check box to cause only routes that are not subnetted to be redistributed.

Choose the name of the route map to apply to the redistribution entry from the Route Map drop-down list.

If you need to add or configure a route map, click

Manage

.

The Configure Route Map dialog box appears. Click

Add

or

Edit

to define which of the routes from the specified routing protocol are allowed to be redistributed into the target routing process. For more information, see the

“Defining a Route Map” section on page 20-4 .

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Step 12

Click

OK

.

Configuring Route Summarization When Redistributing Routes into OSPF

When routes from other protocols are redistributed into OSPF, each route is advertised individually in an external LSA. However, you can configure the adaptive security appliance to advertise a single route for all the redistributed routes that are covered by a specified network address and mask. This configuration decreases the size of the OSPF link-state database.

Routes that match the specified IP Address mask pair can be suppressed. The Tag value can be used as a match value for controlling redistribution through route maps.

There are two areas that you can configure for route summarization:

•

Add a Route Summary Address

•

Add/Edit OSPF Summary Address

Add a Route Summary Address

The Summary Address pane displays information about the summary addresses configured for each

OSPF routing process.

Routes learned from other routing protocols can be summarized. The metric used to advertise the summary is the smallest metric of all the more specific routes. Summary routes help reduce the size of the routing table.

Using summary routes for OSPF causes an OSPF ASBR to advertise one external route as an aggregate for all redistributed routes that are covered by the address. Only routes from other routing protocols that are being redistributed into OSPF can be summarized.

Note

OSPF does not support summary-address 0.0.0.0 0.0.0.0.

To configure the software advertisement on one summary route for all redistributed routes covered by a network address and mask, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

In the main ASDM home page, choose

Configuration > Device Setup > Routing > OSPF > Summary

Address

.

Choose

Add

.

The Add OSPF Summary Address Entry dialog box appears. This allows you to add new entries to existing entries in the Summary Address table. Some of the summary address information cannot be changed when editing an existing entry.

Choose the specified OSPF Process ID associated with the summary address from the OSPF Process drop-down list. You cannot change this information when editing an existing entry.

Enter the IP address of the summary address in the IP Address field. You cannot change this information when editing an existing entry.

Choose the network mask for the summary address from the Netmask drop-down list. You cannot change this information when editing an existing entry.

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21-7



Step 6

Step 7

Step 8

Check or uncheck the

Advertise

check box to advertise the summary route. Uncheck this check box to suppress routes that fall under the summary address. By default this check box is checked.

The Tag value displays a 32-bit decimal value attached to each external route. This value is not used by

OSPF itself. It may be used to communicate information between ASBRs.

Click

OK

.

Add/Edit OSPF Summary Address

To add or edit OSPF summary address setting, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6



.

Click the

Route Summarization

tab.

The Add/Edit a Route Summarization Entry dialog box appears.

The Add/Edit a Route Summarization Entry dialog box allows you to add new entries to or modify existing entries in the Summary Address table. Some of the summary address information cannot be changed when editing an existing entry.

Choose the specified OSPF Process ID associated with the summary address from the OSPF Process drop-down list. You cannot change this information when editing an existing entry.


Enter the network mask for the summary address from the

Netmask

drop-down list. You cannot change this information when editing an existing entry.


Advertise

check box to advertise the summary route. Uncheck this check box to suppress routes that fall under the summary address. By default this check box is checked.

Configuring Route Summarization Between OSPF Areas

Route summarization is the consolidation of advertised addresses. This feature causes a single summary route to be advertised to other areas by an area boundary router. In OSPF, an area boundary router advertises networks in one area into another area. If the network numbers in an area are assigned in a way such that they are contiguous, you can configure the area boundary router to advertise a summary route that covers all the individual networks within the area that fall into the specified range.

To define an address range for route summarization, perform the following steps:

Step 1

Step 2



.

Click the

Route Summarization

tab.

The Add/Edit a Route Summarization Entry dialog box appears.

The Add/Edit a Route Summarization Entry dialog box allows you to add new entries to or modify existing entries in the Summary Address table. Some of the summary address information cannot be changed when editing an existing entry.

21-8


OL-20339-01



Step 3

Step 4

Enter the OSPF Area ID in the Area ID field. You cannot change this information when editing an existing entry.


Configuring OSPF Interface Parameters

You can alter some interface-specific OSPF parameters as necessary.

Prerequisites

You are not required to alter any of these parameters, but the following interface parameters must be consistent across all routers in an attached network: the Hello interval, the Dead interval and the

Authentication key. Be sure that if you configure any of these parameters, the configurations for all routers on your network have compatible values.

To configure OSPF interface parameters, perform the following steps:

In ASDM, the Interface pane lets you configure interface-specific OSPF routing properties, such as

OSPF message authentication and properties. There are two tabs that help you configure interfaces in

OSPF:

•

•

Authentication tab —The Authentication tab displays the OSPF authentication information for the adaptive security appliance interfaces.

Properties tab —The Properties tab displays the OSPF properties defined for each interface in a table format.

Step 1

Step 2

Step 3

Step 4

Step 5


Configuration > Device Setup > Routing > OSPF > Interface

.

Click the

Authentication

tab.

This tab displays the authentication information for the adaptive security appliance interfaces.

Double-clicking a row in the table opens the dialog for the selected interface.

Click

Edit

.

The Edit OSPF Authentication Interface dialog box appears and opens for the selected interface. The

Edit OSPF Interface Authentication dialog box lets you configure the OSPF authentication type and parameters for the selected interface.

Choose the Authentication type from the Authentication drop-down list. Options include:

•

None

—Choose this option to disable OSPF authentication.

•

•

Authentication Password

—Choose this option to use clear text password authentication. This is not recommended where security is a concern.

MD5

—Choose this option to use MD5 authentication (recommended).

•

Area

—(Default) Choose this option to use the authentication type specified for the area (see the

“Configuring OSPF Area Parameters” section on page 21-12 for information about configuring area

authentication). Area authentication is disabled by default. So, unless you have previously specified an area authentication type, interfaces set to area authentication have authentication disabled until you configure area authentication.

Click the radio button in the Authentication Password area.

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21-9



Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Step 12

This area includes the settings for entering the password when password authentication is enabled. The following fields are editable:

•

•

Enter Password—Enter a text string of up to eight characters.

Re-enter Password—Reenter the password.

Choose the settings for MD5 IDs and Keys in the ID area.

This area includes the settings for entering the MD5 keys and parameters when MD5 authentication is enabled. All devices on the interface using OSPF authentication must use the same MD5 key and ID.

Options and fields include:

•

•

Key ID—Enter a numerical key identifier. Valid values range from 1 to 255. This field also displays the Key ID for the interface selected.

Key—An alphanumeric character string of up to 16 bytes. This field also displays the Key ID for the interface selected.

Click the

Add

or

Delete

button to add or delete the specified MD5 key to the MD5 ID and Key table.

Click

OK.

Click the

Properties

tab.

Choose the interface that you want to edit. Double-clicking a row in the table opens the Properties tab dialog box for the selected interface.

Click

Edit

.

The Interface text field displays the name of the interface for which you are configuring OSPF properties. You cannot edit this field.


Broadcast

check box to specify that the interface is a broadcast interface.

By default, this check box is selected for Ethernet interfaces. Uncheck this check box to designate the interface as a point-to-point, non-broadcast interface. Specifying an interface as point-to-point, non-broadcast lets you transmit OSPF routes over VPN tunnels.

When an interface is configured as point-to-point, non-broadcast, the following restrictions apply:

•

You can define only one neighbor for the interface.

•

•

You need to manually configure the neighbor. (See the

“Defining Static OSPF Neighbors” section on page 21-14

.)

You need to define a static route pointing to the crypto endpoint. (See the

“Configuring Static and

Default Routes” section on page 19-2

.)

•

•

If OSPF over the tunnel is running on the interface, regular OSPF with an upstream router cannot be run on the same interface.

You should bind the crypto-map to the interface before specifying the OSPF neighbor to ensure that the OSPF updates are passed through the VPN tunnel. If you bind the crypto-map to the interface after specifying the OSPF neighbor, use the

clear local-host all

command to clear OSPF connections so the OSPF adjacencies can be established over the VPN tunnel.

Configure the following options:

•

Enter a value in the

Cost

field which determines the cost of sending a packet through the interface.

The default value is 10.

•

In the Priority field, enter the OSPF router priority value.

When two routers connect to a network, both attempt to become the designated router. The devices with the higher router priority becomes the designated router. If there is a tie, the router with the higher router ID becomes the designated router.

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Step 13

Step 14

•

Valid values for this setting range from 0 to 255. The default value is 1. Entering 0 for this setting makes the router ineligible to become the designated router or backup designated router. This setting does not apply to interfaces that are configured as point-to-point non-broadcast interfaces.


MTU Ignore

check box.

OSPF checks whether neighbors are using the same MTU on a common interface. This check is performed when neighbors exchange DBD packets. If the receiving MTU in the DBD packet is higher than the IP MTU configured on the incoming interface, OSPF adjacency will not be established.

•

Check or uncheck the D

atabase filter

check box.

This check box to filter outgoing LSA interface during synchronization and flooding. By default,

OSPF floods new LSAs over all interfaces in the same area, except the interface on which the LSA arrives. In a fully meshed topology, this can waste bandwidth and lead to excessive link and CPU usage. Checking this check box prevents flooding OSPF LSA on the selected interface.

(Optional) Click

Advanced

to edit the OSPF Interface Advanced Properties.

The Edit OSPF Interface Advanced Properties dialog box lets you change the values for the OSPF hello interval, retransmit interval, transmit delay, and dead interval. Typically, you only need to change these values from the defaults if you are experiencing OSPF problems on your network.

Enter values for the following:

•

Hello Interval—Specifies the interval, in seconds, between hello packets sent on an interface. The smaller the hello interval, the faster topological changes are detected but the more traffic is sent on the interface. This value must be the same for all routers and access servers on a specific interface.

Valid values range from 1 to 65535 seconds. The default value is 10 seconds.

•

•

Retransmit Interval—Specifies the time, in seconds, between LSA retransmissions for adjacencies belonging to the interface. When a router sends an LSA to its neighbor, it keeps the LSA until it receives the acknowledgement message. If the router receives no acknowledgement, it will resend the LSA. Be conservative when setting this value, or needless retransmission can result. The value should be larger for serial lines and virtual links. Valid values range from 1 to 65535 seconds. The default value is 5 seconds.

Transmit Delay—Specifies the estimated time, in seconds, required to send an LSA packet on the interface. LSAs in the update packet have their ages increased by the amount specified by this field before transmission. If the delay is not added before transmission over a link, the time in which the

LSA propagates over the link is not considered. The value assigned should take into account the transmission and propagation delays for the interface. This setting has more significance on very low-speed links. Valid values range from 1 to 65535 seconds. The default value is 1 second.

•

Dead Interval—Specifies the interval, in seconds, in which no hello packets are received, causing neighbors to declare a router down. Valid values range from 1 to 65535. The default value of this setting is four times the interval set by the Hello Interval field.

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21-11



Configuring OSPF Area Parameters

You can configure several OSPF area parameters. These area parameters (shown in the following task list) include setting authentication, defining stub areas, and assigning specific costs to the default summary route. Authentication provides password-based protection against unauthorized access to an area.

Stub areas are areas into which information on external routes is not sent. Instead, there is a default external route generated by the ABR, into the stub area for destinations outside the autonomous system.

To take advantage of the OSPF stub area support, default routing must be used in the stub area.

To specify area parameters for your network, perform the following steps:

Step 1

Step 2



.

Click the

Area/Networks

tab.

The Add OSPF Area dialog box appears.

Step 3

Select one of the Area Type options.

Options include:

•

•

Normal

—Choose this option to make the area a standard OSPF area. This option is selected by default when you first create an area.

Stub

—Choosing this option makes the area a stub area. Stub areas do not have any routers or areas beyond it. Stub areas prevent AS External LSAs (Type 5 LSAs) from being flooded into the stub area. When you create a stub area, you have the option of preventing summary LSAs (Type 3 and 4) from being flooded into the area by unchecking the Summary check box.

•

•

Summary

—When the area being defined is a stub area, unchecking this check box prevents LSAs from being sent into the stub area. This check box is selected by default for stub areas.

NSSA

—Choose this option to make the area a not-so-stubby area. NSSAs accept Type 7 LSAs.

When you create a NSSA, you have the option of preventing summary LSAs from being flooded into the area by unchecking the Summary check box. You can also disable route redistribution by unchecking the Redistribute check box and enabling Default Information Originate.

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Step 4

Step 5

Step 6

Step 7

Step 8

Enter the IP address in the IP Address field of the network or host to be added to the area. Use

0.0.0.0

with a netmask of

0.0.0.0

to create the default area. You can only enter

0.0.0.0

in one area.

Enter the network mask in the Network Mask field for the IP address or host to be added to the area. If adding a host, choose the

255.255.255.255

mask.

Choose the OSPF Authentication type.

Choices include:

•

None

—This option disables OSPF area authentication. This is the default setting.

•

•

Password

—This option provides a clears text password for area authentication. This option is not recommended where security is a concern.

MD5

—This option allows MD5 authentication.

Enter a value in the Default Cost field to specify a default cost for the OSPF area.

Valid values range from 0 to 65535. The default value is 1.

Click OK.

Configuring OSPF NSSA

The OSPF implementation of an NSSA is similar to an OSPF stub area. NSSA does not flood Type 5 external LSAs from the core into the area, but it can import autonomous system external routes in a limited way within the area.

NSSA imports Type 7 autonomous system external routes within an NSSA area by redistribution. These

Type 7 LSAs are translated into Type 5 LSAs by NSSA ABRs, which are flooded throughout the whole routing domain. Summarization and filtering are supported during the translation.

You can simplify administration if you are an ISP or a network administrator that must connect a central site using OSPF to a remote site that is using a different routing protocol using NSSA.

Before the implementation of NSSA, the connection between the corporate site border router and the remote router could not be run as an OSPF stub area because routes for the remote site could not be redistributed into the stub area, and two routing protocols needed to be maintained. A simple protocol such as RIP was usually run and handled the redistribution. With NSSA, you can extend OSPF to cover the remote connection by defining the area between the corporate router and the remote router as an

NSSA.

Before you use this feature, consider these guidelines:

•

•

You can set a Type 7 default route that can be used to reach external destinations. When configured, the router generates a Type 7 default into the NSSA or the NSSA area boundary router.

Every router within the same area must agree that the area is NSSA; otherwise, the routers will not be able to communicate.

To specify area parameters for your network as needed to configure OSPF NSSA, perform the following steps:

Step 1

Step 2

Step 3

From the main ASDM home page, choose


.

Click the

Area/Networks

tab.

Click

Add

.

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21-13


The Add OSPF Area dialog box appears.


Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Choose

NSSA

in the Area Type area.

Choose this option to make the area a not-so-stubby area. NSSAs accept Type 7 LSAs. When you create a NSSA, you have the option of preventing summary LSAs from being flooded into the area by unchecking the Summary check box. You can also disable route redistribution by unchecking the

Redistribute check box and enabling Default Information Originate.

Enter the IP address in the IP Address field of the network or host to be added to the area. Use

0.0.0.0

with a netmask of

0.0.0.0

to create the default area. You can only enter

0.0.0.0

in one area.

Enter the network mask in the Network Mask field for the IP address or host to be added to the area. If adding a host, choose the

255.255.255.255

mask.

In the Authentication area, click

None

.

Choices include:

•

•

None

—This option disables OSPF area authentication. This is the default setting.

Password

—This option provides a clears text password for area authentication. This option is not recommended where security is a concern.

•

MD5

—This option allows MD5 authentication.

Enter a value in the Default Cost field to specify a default cost for the OSPF area.

Valid values range from 0 to 65535. The default value is 1.

Click

OK

.

Defining Static OSPF Neighbors

You need to define static OSPF neighbors to advertise OSPF routes over a point-to-point, non-broadcast network. This lets you broadcast OSPF advertisements across an existing VPN connection without having to encapsulate the advertisements in a GRE tunnel.

Before you begin, you must create a static route to the OSPF neighbor. See

Chapter 19, “Configuring

Static and Default Routes,”

for more information about creating static routes.


21-14 OL-20339-01



To define a static OSPF neighbor, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6


Configuration > Device Setup > Routing > OSPF > Static

Neighbor

.

Click the

Area/Networks

tab.

The Add/Edit OSPF Neighbor Entry dialog box appears. This dialog box lets you define a new static neighbor or change information for an existing static neighbor. You must define a static neighbor for each point-to-point, non-broadcast interface. Note the following restrictions:

•

You cannot define the same static neighbor for two different OSPF processes.

•

You need to define a static route for each static neighbor.

From the OSPF Process drop-down list, choose the OSPF process associated with the static neighbor. If you are editing an existing static neighbor, you cannot change this value.

In the Neighbor field, enter the IP address of the static neighbor.

In the Interface field, choose the interface associated with the static neighbor. If you are editing an existing static neighbor, you cannot change this value.

Click

OK

.

Configuring Route Calculation Timers

You can configure the delay time between when OSPF receives a topology change and when it starts an

SPF calculation. You also can configure the hold time between two consecutive SPF calculations.

To configure route calculation timers, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5



.

Click the

Process Instances

tab.

Choose the OSPF process that you want to edit, then click

Advanced

.

The Edit OSPF Process Advanced Properties dialog box appears.

In the Timers area, enter the following values:

The Timers area allows you to modify the settings that are used to configure LSA pacing and SPF calculation timers.

•

•

SPF Delay Time—Specifies the time between when OSPF receives a topology change and when the

SPF calculation starts. Valid values range from 0 to 65535. The default value is 5.

SPF Hold Time—Specifies the hold time between consecutive SPF calculations.Valid values range from 1 to 65534. The default value is 10.

•

LSA Group Pacing—Specifies the interval at which LSAs are collected into a group and refreshed, check summed, or aged. Valid values range from 10 to 1800. The default value is 240.

Click

OK

.

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21-15



Logging Neighbors Going Up or Down

By default, a system message is generated when an OSPF neighbor goes up or down.

To log neighbors going up or down, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5



.

Click the


tab.

Click

Advanced

from the OSPF process you want to edit.

The Edit OSPF Process Advanced Properties dialog box appears.

In the Adjacency Changes area, enter the following values:

The Adjacency Changes area includes settings that define the adjacency changes that cause system log messages to be sent.

•

Log Adjacency Changes

—Check this check box to cause the adaptive security appliance to send a system log message whenever an OSPF neighbor goes up or down. This setting is selected by default.

• Log Adjacency Changes Detail

—Check this check box to cause the adaptive security appliance to send a system log message whenever any state change occurs, not just when a neighbor goes up or down. This setting is unchecked by default.

Click

OK

.

Note

Logging must be enabled for the neighbor up/down messages to be sent.

Configuring Filtering in OSPF

The Filtering pane displays the ABR Type 3 LSA filters that have been configured for each OSPF process.

ABR Type 3 LSA filters allow only specified prefixes to be sent from one area to another area and restricts all other prefixes. This type of area filtering can be applied out of a specific OSPF area, into a specific OSPF area, or into and out of the same OSPF areas at the same time.

OSPF ABR Type 3 LSA filtering improves your control of route distribution between OSPF areas.

Note

Only Type 3 LSAs that originate from an ABR are filtered.

To configure filtering in OSPF, perform the following steps:

Step 1

Step 2

Step 3


Configuration > Device Setup > Routing > OSPF > Filtering

.

Click

Add

or

Edit

.

The Add/Edit Filtering Entry dialog box lets you add new filters to the Filter table or to modify an existing filter. Some of the filter information cannot be changed when you edit an existing filter.

Choose the OSPF process that is associated with the filter entry from the OSPF Process drop-down list.

21-16


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Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Choose the Area ID that is associated with the filter entry from the Area ID drop-down list. If you are editing an existing filter entry, you cannot modify this setting.

In the Filtered Network field, enter the address and mask of the network being filtered using CIDR notation (a.b.c.d/m).

Choose the traffic direction being filtered from the Traffic Direction drop-down list.

Choose “Inbound” to filter LSAs coming into an OSPF area, or “Outbound” to filter LSAs coming out of an OSPF area. If you are editing an existing filter entry, you cannot modify this setting.

In the Sequence # field, enter a sequence number for the filter.

Valid values range from 1 to 4294967294. When multiple filters apply to an LSA, the filter with the lowest sequence number is used.

Choose either

Permit

or

Deny

from the Action drop-down list.

Choose

Permit

to allow the LSA traffic or

Deny

to block the LSA traffic.

In the Optional area, choose the following filtering options:

•

•

Lower Range—Specify the minimum prefix length to be matched. The value of this setting must be greater than the length of the network mask entered in the Filtered Network field and less than or equal to the value, if present, entered in the Upper Range field.

Upper Range—Enter the maximum prefix length to be matched. The value of this setting must be greater than or equal to the value, if present, entered in the Lower Range field, or, if the Lower Range field is left blank, greater than the length of the network mask length entered in the Filtered Network field.

Click

OK

.

Configuring a Virtual Link in OSPF

If you add an area to an OSPF network, and it is not possible to connect the area directly to the backbone area, you need to create a virtual link. A virtual link connects two OSPF devices that have a common area, called the transit area. One of the OSPF devices must be connected to the backbone area.

The Add/Edit Virtual Link dialog box lets you define new virtual links or change the properties of existing virtual links.

Step 1

Step 2

Step 3

Step 4

Step 5


Configuration > Device Setup > Routing > OSPF > Virtual Link

.

Choose

Add

or

Edit

.

The Add/Edit OSPF Virtual Link dialog box appears, which allows you to define new virtual links or change the properties of existing virtual links.

Choose the OSPF process ID that is associated with the virtual link from the OSPF Process drop-down list. If you are editing an existing virtual link entry, you cannot modify this setting.

Choose the Area ID that is associated with the virtual link from the Area ID drop-down list.

Choose the area shared by the neighbor OSPF devices. The selected area cannot be an NSSA or a Stub area. If you are editing an existing virtual link, you cannot change this value. If you are editing an existing virtual link entry, you cannot modify this setting.

In the Peer Router ID field, enter the router ID of the virtual link neighbor.

If you are editing an existing virtual link entry, you cannot modify this setting.


OL-20339-01 21-17



Step 6

Step 7

Step 8

Step 9

Step 10

Choose

Advanced

to edit advanced virtual link properties,

The Advanced OSPF Virtual Link Properties dialog box appears. You can configure the OSPF properties for the virtual link in this area. These properties include authentication and packet interval settings

In the

Authentication

area, choose the Authentication type by clicking the radio button next to your choice. OSPF authentication options include:

•

•

None

—Choose this option to disable OSPF authentication.

Authentication Password

—Choose this option to use clear text password authentication. This is not recommended where security is a concern.

•

•

•

MD5

—Choose this option to use MD5 authentication (recommended).

Area

—(Default) Choose this option to use the authentication type specified for the area (see the

“Configuring OSPF Area Parameters” section on page 21-12

for information about configuring area authentication). Area authentication is disabled by default. So, unless you have previously specified an area authentication type, interfaces set to area authentication have authentication disabled until you configure area authentication.

In the Authentication Password area enter and re-enter a password when password authentication is enabled from Step 7. Passwords must be a text string of up to 8 characters.

In the MD5 IDs and Keys area, enter the MD5 keys and parameters when MD5 authentication is enabled from Step 7. All devices on the interface using OSPF authentication must use the same MD5 key and ID.

Fields include:

•

Key ID—Enter a numerical key identifier. Valid values range from 1 to 255. This field also displays the Key ID for the interface selected.

Key—An alphanumeric character string of up to 16 bytes. This field also displays the Key ID for the interface selected.

Click the

Add

or

Delete

button to add or delete the specified MD5 key to the MD5 ID and Key table.

In the Interval area, choose the interval timing for the packet by choosing from the following options:

•

•

Hello Interval—Specifies the interval, in seconds, between hello packets sent on an interface. The smaller the hello interval, the faster topological changes are detected but the more traffic is sent on the interface. This value must be the same for all routers and access servers on a specific interface.


Retransmit Interval—Specifies the time, in seconds, between LSA retransmissions for adjacencies belonging to the interface. When a router sends an LSA to its neighbor, it keeps the LSA until it receives the acknowledgement message. If the router receives no acknowledgement, it will resend the LSA. Be conservative when setting this value, or needless retransmission can result. The value should be larger for serial lines and virtual links. Valid values range from 1 to 65535 seconds. The default value is 5 seconds.

•

•

Transmit Delay—Specifies the estimated time, in seconds, required to send an LSA packet on the interface. LSAs in the update packet have their ages increased by the amount specified by this field before transmission. If the delay is not added before transmission over a link, the time in which the

LSA propagates over the link is not considered. The value assigned should take into account the transmission and propagation delays for the interface. This setting has more significance on very low-speed links. Valid values range from 1 to 65535 seconds. The default value is 1 second.

Dead Interval—Specifies the interval, in seconds, in which no hello packets are received, causing neighbors to declare a router down. Valid values range from 1 to 65535. The default value of this field is four times the interval set by the Hello Interval field.

21-18


OL-20339-01


Restarting the OSPF Process

Step 11

Click

OK

.

Restarting the OSPF Process

To remove the entire OSPF configuration that you have enabled, perform the following steps:

Step 1

Step 2



.

Click

Reset

.

Configuration Example for OSPF

The following example shows how to enable and configure OSPF with various optional processes:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 11

Step 12

Step 13

Step 14

Step 15

Step 16

Step 17

Step 18

Step 9

Step 10

Step 19



.

Click the


tab and in the OSPF Process 1 field, type

2

.

Click the

Area/Networks

tab, and click

Add

.

Enter

0

in the Area ID field.

In the Area Networks area, enter

10.0.0.0

in the IP Address field.

Choose 255.0.0.0 from the Netmask drop-down list.

Click

OK

.


Configuration > Device Setup > Routing > OSPF >

Redistribution

.

Click

Add

.

The Add/Edit OSPF Redistribution Entry dialog box appears.

In the Protocol area, click the

OSPF

radio button to choose the source protocol the routes are being redistributed from. Choosing OSPF redistributes routes from another OSPF routing process.

Choose the OSPF process ID from the OSPF Process drop-down list.

In the Match area, check the

Internal

check box.

In the Metric Value field, enter

5

for the metric value of for the routes being redistributed.

From the Metric Type drop-down list, choose 1 for the Metric Type value.

From the Route Map drop-down list, choose 1.

Click OK.



.

From the Properties tab, choose the

inside

interface and click

Edit.

The Edit OSPF Properties dialog box appears.

In the Cost field, enter

20

.

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21-19


Monitoring OSPF

Step 20

Step 21

Step 22

Step 23

Step 24

Step 25

Step 26

Step 27

Step 28

Step 34

Step 35

Step 36

Step 37

Step 38

Step 39

Step 29

Step 30

Step 31

Step 32

Step 33

Step 40

Step 41

Step 42

Step 43

Click

Advanced

.

In the Retransmit Interval field, enter

15

.

In the Transmit Delay field, enter

20

.

In the Hello Interval field, enter

10

.

In the Dead Interval field, enter

40

.

Click

OK

.

In the Edit OSPF Properties dialog box, enter

20

in the Priorities field, and click

OK

.

Choose


.

Click the

Authentication

tab.

The Edit OSPF Authentication dialog box appears.

In the Authentication area, click on the

MD5

radio button.

In the MD5 and Key ID area, type

cisco

in the MD5 Key field, and type

1

in the MD5 Key ID field.

Click

OK

.

Choose

Configuration > Device Setup > Routing > OSPF > Setup,

and click the

Area/Networks

tab.

Choose

OSPF 2

process and click

Edit

.

The Edit OSPF Area dialog box appears.

In the Area Type area, choose

Stub

.

In the Authentication area, choose None, and enter

20

in the Default Cost field.

Click

OK

.



.

Click the


tab and check the

OSPF process 2

check box.

Click

Advanced

.

The Edit OSPF Area dialog box appears.

In the Timers area, enter

10

in the SPF Delay Time field and

20

in the SPF Hold Time field.

In the Adjacency Changes area, check the

Log Adjacency Change Details

check box.

Click

OK

.



, then click

Reset

.

Monitoring OSPF

You can display specific statistics such as the contents of IP routing tables, caches, and databases. You can also use the information provided to determine resource utilization and solve network problems. You can also display information about node reachability and discover the routing path that your device packets are taking through the network.

To monitor or display various OSPF routing statistics in ASDM, perform the following steps:

Step 1


Monitoring > Routing

.

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OL-20339-01


Step 2

From here you can select and monitor the following:

•

•

OSPF LSAs Types 1 through 7

OSPF Neighbors

Feature History for OSPF


Table 21-1


Table 21-1

Feature Name

OSPF Support

Feature History for Static and Default Routes

Platform

Releases

7.0(1)


Support was added for route data, perform authentication, redistribute and monitor routing information, using the

Open Shortest Path First (OSPF) routing protocol.

The

Configuration > Device Setup > Routing > OSPF


OL-20339-01


21-21



21-22


OL-20339-01

C H A P T E R

22

Configuring RIP

This chapter describes how to configure the adaptive security appliance to route data, perform authentication, and redistribute routing information, using the Routing Information Protocol (RIP).


•

•

•

•

•

Overview, page 22-1

Licensing Requirements for RIP, page 22-2


Configuring RIP, page 22-3

•

•

•

Customizing RIP, page 22-5

Monitoring RIP, page 22-12

Configuration Example for RIP, page 22-13

Feature History for RIP, page 22-13

Overview

The Routing Information Protocol, or RIP, as it is more commonly called, is one of the most enduring of all routing protocols. RIP has four basic components: routing update process, RIP routing metrics, routing stability, and routing timers. Devices that support RIP send routing-update messages at regular intervals and when the network topology changes. These RIP packets contain information about the networks that the devices can reach, as well as the number of routers or gateways that a packet must travel through to reach the destination address. RIP generates more traffic than OSPF, but is easier to configure.

RIP is a distance-vector routing protocol that uses hop count as the metric for path selection. When RIP is enabled on an interface, the interface exchanges RIP broadcasts with neighboring devices to dynamically learn about and advertise routes.

The adaptive security appliance support both RIP Version 1 and RIP Version 2. RIP Version 1 does not send the subnet mask with the routing update. RIP Version 2 sends the subnet mask with the routing update and supports variable-length subnet masks. Additionally, RIP Version 2 supports neighbor authentication when routing updates are exchanged. This authentication ensures that the adaptive security appliance receives reliable routing information from a trusted source.

RIP has advantages over static routes because the initial configuration is simple, and you do not need to update the configuration when the topology changes. The disadvantage to RIP is that there is more network and processing overhead than static routing.

OL-20339-01


22-1

Chapter 22 Configuring RIP

Licensing Requirements for RIP

Routing Update Process

RIP sends routing-update messages at regular intervals and when the network topology changes. When a router receives a routing update that includes changes to an entry, it updates its routing table to reflect the new route. The metric value for the path is increased by 1, and the sender is indicated as the next hop.

RIP routers maintain only the best route (the route with the lowest metric value) to a destination. After updating its routing table, the router immediately begins transmitting routing updates to inform other network routers of the change. These updates are sent independently of the regularly scheduled updates that RIP routers send.

RIP Routing Metric

RIP uses a single routing metric (hop count) to measure the distance between the source and a destination network. Each hop in a path from source to destination is assigned a hop count value, which is typically

1. When a router receives a routing update that contains a new or changed destination network entry, the router adds 1 to the metric value indicated in the update and enters the network in the routing table. The

IP address of the sender is used as the next hop.

RIP Stability Features

RIP prevents routing loops from continuing indefinitely by implementing a limit on the number of hops allowed in a path from the source to a destination. The maximum number of hops in a path is 15. If a router receives a routing update that contains a new or changed entry, and if increasing the metric value by 1 causes the metric to be infinity (that is, 16), the network destination is considered unreachable. The downside of this stability feature is that it limits the maximum diameter of a RIP network to less than 16 hops.

RIP includes a number of other stability features that are common to many routing protocols. These features are designed to provide stability despite potentially rapid changes in network topology. For example, RIP implements the split horizon and hold-down mechanisms to prevent incorrect routing information from being propagated.

RIP Timers

RIP uses numerous timers to regulate its performance. These include a routing-update timer, a route-timeout timer, and a route-flush timer. The routing-update timer clocks the interval between periodic routing updates. Generally, it is set to 30 seconds, with a small random amount of time added whenever the timer is reset. This is done to help prevent congestion, which could result from all routers simultaneously attempting to update their neighbors. Each routing table entry has a route-timeout timer associated with it. When the route-timeout timer expires, the route is marked invalid but is retained in the table until the route-flush timer expires.

Licensing Requirements for RIP

Model

All models


Base License.

22-2


OL-20339-01








Supported in routed and transparent mode.

IPv6 Guidelines



The following information applies to RIP Version 2 only:

•

If using neighbor authentication, the authentication key and key ID must be the same on all neighbor devices that provide RIP Version 2 updates to the interface.

•

•

With RIP Version 2, the adaptive security appliance transmits and receives default route updates using the multicast address 224.0.0.9. In passive mode, it receives route updates at that address.

When RIP Version 2 is configured on an interface, the multicast address 224.0.0.9 is registered on that interface. When a RIP Version 2 configuration is removed from an interface, that multicast address is unregistered.

•

•

•

Limitations

RIP has the following limitations:

The adaptive security appliance cannot pass RIP updates between interfaces.

RIP Version 1 does not support variable-length subnet masks.

•

•

RIP has a maximum hop count of 15. A route with a hop count greater than 15 is considered unreachable.

RIP convergence is relatively slow compared to other routing protocols.

You can only enable a single RIP process on the adaptive security appliance.

Configuring RIP

This section describes how to enable and restart the RIP process on the adaptive security appliance.

After you have enabled RIP, see the

“Customizing RIP” section on page 22-5 , to learn how to customize

the RIP process on the adaptive security appliance.

Note

If you want to redistribute a route by defining which of the routes from the specified routing protocol are allowed to be redistributed into the target routing process, you must first generate a default route. For information, see the

“Configuring a Default Static Route” section on page 19-7 and then define a route

map. For information, see the

“Defining a Route Map” section on page 20-4 .

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22-3


Configuring RIP

Enabling RIP

You can only enable one RIP routing process on the adaptive security appliance. After you enable the

RIP routing process, you must define the interfaces that will participate in that routing process using the

network

command. By default, the adaptive security appliance sends RIP Version 1 updates and accepts

RIP Version 1 and Version 2 updates.

In ASDM, to enable a RIP process, perform the following steps:

Step 1


Configuration > Device Setup > Routing > RIP > Setup

.

The main RIP Setup pane appears.

Step 2

Step 3

From this pane you can perform the following tasks:

•

•

•

Enable Auto-summarization—See the

“Configuring Route Summarization” section on page 22-8

Enable RIP version—See the

“Configure the RIP Version” section on page 22-5

.

.

•

Enable default information origination.

Define an IP Address for a Network to Add—See the

“Filtering Networks in RIP” section on page 22-9 .

•

Configure an Interface—See the “Configuring Interfaces for RIP” section on page 22-6 .

Check the

Enable RIP routing

check box.

After the Enable RIP routing box has been checked, you can enable RIP on the adaptive security appliance and configure global RIP protocol parameters. You can only enable a single RIP process on the adaptive security appliance. When you enable RIP, it is enabled on all interfaces. Checking this check box also enables the other fields in this pane. Uncheck this check box to disable RIP routing on the adaptive security appliance.

Click

Apply

.

To customize the RIP process, see the

“Configuring RIP” section on page 22-3

.

22-4


OL-20339-01


Customizing RIP

This section describes how to configure RIP and includes the following topics:

•

Configure the RIP Version, page 22-5

•

•

•

•

•

•

•

Configuring Interfaces for RIP, page 22-6

Configuring the RIP Send and Receive Version on an Interface, page 22-7

Configuring Route Summarization, page 22-8

Filtering Networks in RIP, page 22-9

Redistributing Routes into the RIP Routing Process, page 22-10

Enabling RIP Authentication, page 22-11

Restarting the RIP Process, page 22-12

Customizing RIP

Configure the RIP Version

In ASDM, you can specify the version of RIP used by the adaptive security appliance by performing the following steps:

Step 1

Step 2

Step 3

Step 4



.

Check the


check box, and click

Apply

.

Check the

Enable RIP version

check box.

Checking this check box specifies the version of RIP used by the adaptive security appliance. If this check box is cleared, then the adaptive security appliance sends RIP Version 1 updates and accepts RIP

Version 1 and Version 2 updates. This setting can be overridden on a per-interface basis in the Interface pane. For more information about configuring interfaces, see the

“Configuring Interfaces for RIP” section on page 22-6 .

•

Version 1—Specifies that the adaptive security appliance only sends and receives RIP Version 1 updates. Any Version 2 updates received are dropped.

•

Version 2—Specifies that the adaptive security appliance only sends and receives RIP Version 2 updates. Any Version 1 updates received are dropped.

Click

Apply

.

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22-5


Customizing RIP

Configuring Interfaces for RIP

If you have an interface that you do not want to participate in RIP routing, but that is attached to a network that you want advertised, you can configure the network that covers the network the interface is attached to, and configure the passive interfaces to prevent that interface from sending RIP.

Additionally, you can specify the version of RIP that is used by the adaptive security appliance for updates.

In ASDM, you can configure an interface in RIP used by the adaptive security appliance so that all interfaces on the adaptive security appliance are set to passive RIP mode. The adaptive security appliance listens for RIP routing broadcasts on all interfaces and uses that information to populate the routing tables but do not broadcast routing updates. To set specific interfaces to passive RIP, perform the following steps:

Step 1

Step 2

Step 3

Step 4



.

Check the


check box.

In the Passive Interfaces area, check the check box in the

Passive

column for those interfaces that you want to have operate in passive mode. The other interfaces will still send and receive RIP broadcasts.

Click

Apply

.

Note

Individual interfaces can be made passive only if the global passive mode is not enabled. Uncheck the

Global Passive check box to make individual interfaces passive using the Passive Interfaces table.

You can override this setting on a per-interface basis in the Interface pane. For more information, see the

“Editing a RIP Interface” section on page 22-6

.

Editing a RIP Interface

In ASDM, the Interface pane allows you to configure interface-specific RIP settings, such as the version of RIP that the interface sends and receives and the authentication method, if any, that are used for the

RIP broadcasts.

To edit an interface that you have previously set up and configured, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5



.

Check the


check box and click

Apply

.

Choose

Configuration > Device Setup > Routing > RIP > Interfaces

.

Click

Add

or

Edit

.

The Add or Edit RIP Interface Entry dialog box appears and allows you to configure the interface-specific RIP settings.

(Optional) Choose the following options according to your preferences:

•

Override Global Send Version

—Check this check box to specify the RIP version sent by the interface. You can choose the following options:

–

Version 1

22-6


OL-20339-01


Customizing RIP

Step 6

•

•

–

Version 2

–

Version 1 & 2

Unchecking this check box restores the global setting.

Override Global Receive Version

—Check this check box to specify the RIP version accepted by the interface. If a RIP updated from an unsupported version of RIP is received by the interface, it is dropped. Choose one of the following options:

–

Version 1

–

–

Version 2

Version 1 & 2


Enable Authentication

—Check this check box to enable RIP authentication. Uncheck this check box to disable RIP authentication.

–

–

Key—The key used by the authentication method, which can be up to 16 characters long.

Key ID—The key ID. Valid values are from 0 to 255.

–

Authentication Mode—You can choose one of the following authentication modes:

MD5—Uses MD5 for RIP message authentication.

Text—Uses cleartext for RIP message authentication (not recommended).

Click

Apply

.

Configuring the RIP Send and Receive Version on an Interface

You can override the globally-set version of RIP that the adaptive security appliance uses to send and receive RIP updates on a per-interface basis.

To configure the RIP version for sending and receiving updates, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5



.

Check the


box, and click

Apply

.

Choose

Configuration > Device Setup > Routing > RIP > Interfaces

.

Click

Edit

.

The Edit RIP Interface Entry dialog box appears and allows you to configure the interface-specific RIP settings for sending and receiving.

In the Send Version area, check the

Override global send version

check box to specify the RIP version sent by the interface. Choose one of the following:

•

Version 1

•

•

Version 2

Version 1 & 2


OL-20339-01


22-7


Customizing RIP

Step 6

Step 7

In the Receive Version area, check the

Override global receive version

check box to specify the RIP version accepted by the interface. If a RIP updated from an unsupported version of RIP is received by the interface, it is dropped. Choose one of from the following:

•

•

•

Version 1

Version 2

Version 1 & 2


Click

Apply

.

Configuring Route Summarization

Note

RIP Version 1 always uses automatic route summarization. You cannot disable this feature for RIP

Version 1. RIP Version 2 uses automatic route summarization by default.

The RIP routing process summarizes on network number boundaries, which can cause routing problems if you have noncontiguous networks.

For example, if you have a router with the networks 192.168.1.0, 192.168.2.0, and 192.168.3.0 connected to it, and those networks all participate in RIP, the RIP routing process creates the summary address 192.168.0.0 for those routes. If an additional router is added to the network with the networks

192.168.10.0 and 192.168.11.0, and those networks participate in RIP, they will also be summarized as

192.168.0.0. To prevent the possibility of traffic being routed to the wrong location, you should disable automatic route summarization on the routers that are creating conflicting summary addresses.

Because RIP Version 1 always uses automatic route summarization, and RIP Version 2 always uses automatic route summarization by default, when configuring automatic route summarization, you only need to disable it.

In ASDM, you can enable or disable automatic route summarization in a RIP process using the following steps:

Step 1

Step 2

Step 3

Step 4



.

Check the



Apply

.

Check the

Enable Auto-Summarization

check box.

Uncheck this check box to disable automatic route summarization. Check this check box to reenable automatic route summarization. RIP Version 1 always uses automatic summarization. You cannot disable automatic route summarization for RIP Version 1. If you are using RIP Version 2, you can turn off automatic route summarization by unchecking this check box. Disable automatic route summarization if you must perform routing between disconnected subnets. When automatic route summarization is disabled, subnets are advertised.

Click

Apply

.

22-8


OL-20339-01


Filtering Networks in RIP

To filter the networks received in updates, perform the following steps:

Customizing RIP

Note

Before you begin, you must create a standard access list that permits the networks that you want the RIP process to allow in the routing table and denies the networks that you want the RIP process to discard.

In ASDM, you can configure filter rules that allow you to filter the network received in RIP routing updates or sent in RIP routing updates. Each filter rule consists of one or more network rules.

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9



.

Check the



Apply

.

Choose

Configuration > Device Setup > Routing > RIP > Filter Rules

.

Click

Add

or

Edit

.

The Add or Edit Filter Rule dialog box appears. This dialog box allows you to create or edit filter rules that apply to all interfaces or to a specific interface.

From the Direction drop-down list, choose the direction in which the filter should act.

Choosing “In” filters networks on incoming RIP updates. Additionally, if you choose “In,” only the

Interface drop-down list is visible.

If you choose “Out” as the filter direction, skip to Step 8.

Choose the Interface type from the Interface drop-down list.

This allows you to choose a specific interface for the filter rule, or you can choose the All Interfaces option to apply the filter to all interfaces.

(Optional) Add a network rule by clicking

Add

. Skip to the

“Adding or Editing a Filter Rule” section on page 22-10

.

Choose “Out” to filter networks from outgoing RIP updates.

When you choose “Out” as the filter direction, the Interface and Routing Process drop-down list becomes visible.

•

Click the

Interface

radio button to choose a specific interface for the filter rule from the Interface drop-down list, or you can click the

All Interfaces

option to apply the filter to all interfaces.

•

Click the

Routing Process

radio button to activate the Routing process drop-down list. Choose from the following routing process types:

–

connected

–

–

–

–

static

OSPF

RIP

EIGRP

(Optional) Add a network rule by clicking

Add

. Skip to the

“Adding or Editing a Filter Rule” section on page 22-10

.

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22-9


Customizing RIP

Adding or Editing a Filter Rule

After you have configured a filter rule (see the

“Filtering Networks in RIP” section on page 22-9 ), you

can add or edit a network rule below the selected rule in the list.

Step 1

Step 2

Step 3

Step 4

Step 5

After you have selected the direction or Interface type from Step 5 or Step 8, click

Add

or

Edit

in the

Filtering Networks in RIP area.

The Network Rule dialog box appears.

Choose the action from the Action drop-down list. The default is Permit.

•

Choose

Permit

if the specified network is not filtered from incoming or outgoing RIP advertisements.

•

Choose

Deny

if the specified network is to be filtered from incoming or outgoing RIP advertisements.

Enter the IP Address for the network being filtered, if different than what is displayed, in the IP Address field.

By default, the IP Address field displays the IP Address for the network being filtered.

Enter the netmask if different than what is displayed, in the Netmask field.

By default, the Netmask field displays the network mask applied to the IP address.

Click

OK

.

Redistributing Routes into the RIP Routing Process

You can redistribute routes from the OSPF, EIGRP, static, and connected routing processes into the RIP routing process.

Note

Before you begin this procedure, you must create a route-map to further define which routes from the specified routing protocol are redistributed in to the RIP routing process. See

Chapter 20, “Defining

Route Maps,”

for more information about creating a route map.

In ASDM, you can display the routes that are being redistributed from other routing processes into the

RIP routing process by performing the following steps:

Step 1

Step 2

Step 3


Configuration > Device Setup > Routing > RIP > Redistribution

.

The Redistribution pane displays the routes that are being redistributed from other routing processes into the RIP routing process.

Click

Add

or

Edit

.

If you clicked

Add

, the Add Route Redistribution dialog box allows you to add a new redistribution rule.

If you clicked

Edit

, the Edit Route Redistribution dialog box allows you to change an existing rule.

In the Protocol area, choose the routing protocol to redistribute into the RIP routing process:

•

Static—Static routes.

•

Connected—Directly connected networks.

22-10


OL-20339-01


Customizing RIP

Step 4

Step 5

Step 6

Step 7

•

•

EIGRP and EIGRP ID—Routes discovered by the EIGRP routing process. If you choose EIGRP, you must also specify the autonomous system number of the EIGRP routing process in the EIGRP

ID field.

In the Metrics area, check the

Configure Metric Type

check box to specify a metric for the redistributed routes. If not specified, the routes are assigned a default metric of 0. When the check box is checked, the available values include the following:

•

•

OSPF and OSPF ID—Routes discovered by the OSPF routing process. If you choose OSPF, you must also enter the OSPF process ID. Additionally, you can select the specific types of OSPF routes to redistribute from the Match area.

Transparent

—Choose this option to cause the current route metric to be used.

Value

—Choose this option to assign a specific metric value. You can enter a value from 0 to 16.

In the Optional area, choose the route map from the Route Map drop-down list. This route map specifies the name of a route map that must be specified before the route can be redistributed into the RIP routing process. Click

Manage

to configure a specific route map. For more information about configuring route maps, see the

“Add/Edit a Route Map” section on page 20-4 .

In the Match area, choose specific types of OSPF routes to redistribute by checking the check box next to the route type. This area is not active unless OSPF has been chosen in the Protocol area.

If you do not check any route types, Internal, External 1, and External 2 routes are redistributed by default. The Match types are:

•

Internal—Routes internal to the AS are redistributed.

•

•

•

•

External 1—Type 1 routes external to the AS are redistributed.

External 2—Type 2 routes external to the AS are redistributed.

NSSA External 1—Type 1 routes external to an NSSA are redistributed.

NSSA External 2—Type 2 routes external to an NSSA are redistributed.

Click

OK

.

Enabling RIP Authentication

Note

The adaptive security appliance supports RIP message authentication for RIP Version 2 messages.

RIP route authentication provides MD5 authentication of routing updates from the RIP routing protocol.

The MD5 keyed digest in each RIP packet prevents the introduction of unauthorized or false routing messages from unapproved sources.

RIP route authentication is configured on a per-interface basis. All RIP neighbors on interfaces configured for RIP message authentication must be configured with the same authentication mode and key for adjacencies to be established.

Note

Before you can enable RIP route authentication, you must enable RIP.

To enable RIP authentication on an interface, perform the following steps:

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22-11


Monitoring RIP

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9



.

Check the



Apply

. If you uncheck this check box, the adaptive security appliance sends RIP Version 1 updates and accepts RIP Version 1 and Version 2 updates. You can override this setting on a per-interface basis in the Interface pane. Version 1 specifies that the adaptive security appliance only sends and receives RIP Version 1 updates. Any Version 2 updates received are dropped. Version 2 specifies that the adaptive security appliance only sends and receives

RIP Version 2 updates. Any Version 1 updates received are dropped.

Choose

Configuration > Device Setup > Routing > RIP > Interface

.

Click

Edit

.

The Edit RIP Interface Entry dialog box appears, which allows you to configure the interface-specific

RIP settings.

In the Authentication area, check the

Enable Authentication

check box to enable RIP authentication.

Uncheck this check box to disable RIP authentication.

In the Key field, enter the key used by the authentication method.

This entry can include up to 16 characters.

In the Key ID field, enter the key ID. Valid values range from 0 to 255.

Choose the type of Authentication mode that you want to use by clicking the radio button next to one of the following:

•

MD5

to use MD5 for RIP message authentication.

• cleartext

to use cleartext for RIP message authentication (not recommended).

Click

Apply

.

Restarting the RIP Process

To remove the entire RIP configuration, perform the following steps:

Step 1

Step 2



.

Click

Reset

.

Monitoring RIP

To monitor or display various RIP routing statistics in ASDM, perform the following steps:

Step 1

Step 2


Monitoring > Routing > Routes

.

From this pane, you can choose to monitor the following:

•

IPv4

• IPv6

22-12


OL-20339-01


Configuration Example for RIP

•

Both

Configuration Example for RIP

The following example shows how to enable and configure RIP with various optional processes:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Step 12

Step 13

Step 14



.

Check the


check box and click

Apply

.

Check the

Enable default information originate

check box.

For more information about defining a route map, see the

“Defining Route Maps” section on page 20-1 .

Check the

Enable RIP version


Version 1

.

In the Networks area, enter

225.25.24.225

in the IP Network to Add field.

In the Passive Interface area, click the check box next to the interface that you want to be passive in the

Passive Interfaces table.

Click

Apply

.

Choose

Configuration > Device Setup > Routing > RIP > Redistribution

.

Click

Edit

.

In the Protocol area, choose

Connected

.

In the Metric area, check the

Configure Metric Type


Transparent Mode

(default).

In the Optional area, choose a route map from the Route Map drop-down list.

Click

Manage

to configure a specific route map. For more information about configuring route maps,

see the “Add/Edit a Route Map” section on page 20-4 .

Click

OK

.

Feature History for RIP

Table 22-1


Table 22-1

Feature Name

RIP Support

Feature History for RIP

Releases

7.0(1)


Support for routing data, performing authentication, and redistributing and monitoring routing information using the

Routing Information Protocol (RIP).

The

Configuration > Device Setup > Routing > RIP


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22-13

Feature History for RIP


22-14


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C H A P T E R

23


This chapter describes how to configure the adaptive security appliance to route data, perform authentication, and redistribute routing information, using the Enhanced Interior Gateway Routing

Protocol (EIGRP).


•

•

•

•

•

Overview, page 23-1

Licensing Requirements for EIGRP, page 23-2


Task List to Configure an EIGRP Process, page 23-3

•

•

•

•

Enabling EIGRP, page 23-4

Customizing EIGRP, page 23-6

Monitoring EIGRP, page 23-18

Configuration Example for EIGRP, page 23-18

Feature History for EIGRP, page 23-20

Overview

EIGRP is an enhanced version of IGRP developed by Cisco. Unlike IGRP and RIP, EIGRP does not send out periodic route updates. EIGRP updates are sent out only when the network topology changes. Key capabilities that distinguish EIGRP from other routing protocols include fast convergence, support for variable-length subnet mask, support for partial updates, and support for multiple network layer protocols.

A router running EIGRP stores all the neighbor routing tables so that it can quickly adapt to alternate routes. If no appropriate route exists, EIGRP queries its neighbors to discover an alternate route. These queries propagate until an alternate route is found. Its support for variable-length subnet masks permits routes to be automatically summarized on a network number boundary. In addition, EIGRP can be configured to summarize on any bit boundary at any interface. EIGRP does not make periodic updates.

Instead, it sends partial updates only when the metric for a route changes. Propagation of partial updates is automatically bounded so that only those routers that need the information are updated. As a result of these two capabilities, EIGRP consumes significantly less bandwidth than IGRP.

Neighbor discovery is the process that the adaptive security appliance uses to dynamically learn of other routers on directly attached networks. EIGRP routers send out multicast hello packets to announce their presence on the network. When the adaptive security appliance receives a hello packet from a new

OL-20339-01


23-1

Chapter 23 Configuring EIGRP

Licensing Requirements for EIGRP

neighbor, it sends its topology table to the neighbor with an initialization bit set. When the neighbor receives the topology update with the initialization bit set, the neighbor sends its topology table back to the adaptive security appliance.

The hello packets are sent out as multicast messages. No response is expected to a hello message. The exception to this is for statically defined neighbors. If you use the

neighbor

command, or configure the

Hello Interval in ASDM, to configure a neighbor, the hello messages sent to that neighbor are sent as unicast messages. Routing updates and acknowledgements are sent out as unicast messages.

Once this neighbor relationship is established, routing updates are not exchanged unless there is a change in the network topology. The neighbor relationship is maintained through the hello packets. Each hello packet received from a neighbor contains a hold time. This is the time in which the adaptive security appliance can expect to receive a hello packet from that neighbor. If the adaptive security appliance does not receive a hello packet from that neighbor within the hold time advertised by that neighbor, the adaptive security appliance considers that neighbor to be unavailable.

The EIGRP protocol uses four key algorithm technologies, four key technologies, including neighbor discover/recovery, Reliable Transport Protocol (RTP), and the fourth one, DUAL being important for route computations. DUAL saves all routes to a destination in the topology table, not just the least-cost route. The least-cost route is inserted into the routing table. The other routes remain in the topology table. If the main route fails, another route is chosen from the feasible successors. A successor is a neighboring router used for packet forwarding that has a least-cost path to a destination. The feasibility calculation guarantees that the path is not part of a routing loop.

If a feasible successor is not found in the topology table, a route recomputation must occur. During route recomputation, DUAL queries the EIGRP neighbors for a route, who in turn query their neighbors.

Routers that do no have a feasible successor for the route return an unreachable message.

During route recomputation, DUAL marks the route as active. By default, the adaptive security appliance waits for three minutes to receive a response from its neighbors. If the adaptive security appliance does not receive a response from a neighbor, the route is marked as stuck-in-active. All routes in the topology table that point to the unresponsive neighbor as a feasibility successor are removed.

Note

EIGRP neighbor relationships are not supported through the IPSec tunnel without a GRE tunnel.

Licensing Requirements for EIGRP

Model

All models


Base License.







23-2


OL-20339-01


Task List to Configure an EIGRP Process

IPv6 Guidelines


Task List to Configure an EIGRP Process

To configure EIGRP routing on the adaptive security appliance, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9


Configuration > Device Setup > Routing > EIGRP

.

Enable the EIGRP routing process by checking

Enable this EIGRP process check box

on the

Process

Instances

tab. See the

“Enabling EIGRP” section on page 23-4 or the

“Enabling EIGRP Stub Routing” section on page 23-5 .

Define the networks and interfaces that will participate in EIGRP routing on the

Setup > Networks

tab.

See the

“Defining a Network for an EIGRP Routing Process” section on page 23-7 for more information.

(Optional) Define route filters on the

Filter Rules

pane. Route filtering provides more control over the routes that are allowed to be sent or received in EIGRP updates. See the

“Filtering Networks in EIGRP” section on page 23-13


(Optional) Define route redistribution in the

Redistribution

pane.

You can redistribute routes discovered by RIP and OSPF to the EIGRP routing process. You can also redistribute static and connected routes to the EIGRP routing process. See the

“Redistributing Routes

Into EIGRP” section on page 23-12


(Optional) Define static EIGRP neighbors on the

Static Neighbor

pane.

See the

“Defining an EIGRP Neighbor” section on page 23-11


(Optional) Define summary addresses on the

Summary Address

pane.

See the

“Configuring the Summary Aggregate Addresses on Interfaces” section on page 23-9

for more information about defining summary addresses.

(Optional) Define interface-specific EIGRP parameters on the

Interfaces

pane. These parameters include EIGRP message authentication, hold time, hello interval, delay metric, and the use of split-horizon. See the

“Configuring Interfaces for EIGRP” section on page 23-7


(Optional) Control the sending and receiving of default route information in EIGRP updates on the

Default Information

pane. By default, default routes are sent and accepted. See the “Configuring

Default Information in EIGRP” section on page 23-16



This section explains how to enable the EIGRP process on your system. After you have enabled EIGRP, see the following sections to learn how to customize the EIGRP process on your system.

•

•

Enabling EIGRP, page 23-4

Enabling EIGRP Stub Routing, page 23-5

OL-20339-01


23-3



Enabling EIGRP

You can only enable one EIGRP routing process on the adaptive security appliance.

To enable EIGRP,perform the following steps:

Step 1


Configuration > Device Setup > Routing > EIGRP > Setup

.

The EIGRP Setup pane appears.

Step 2

Step 3

Step 4

The three tabs on the main EIGRP Setup pane used to enable EIGRP are as follows:

•

•

Process Instances tab—This tab lets you enable an EIGRP routing process. See

page 23-4 and

Enabling EIGRP Stub Routing, page 23-5


Enabling EIGRP,

Networks tab—The Network tab lets you specify the networks used by the EIGRP routing process.

For an interface to participate in EIGRP routing, it must fall within the range of addresses defined by the network entries. For directly connected and static networks to be advertised, they must also fall within the range of the network entries. See

Defining a Network for an EIGRP Routing Process, page 23-7 for more information.

•

Passive Interfaces tab—This lets you configure one or more interfaces as passive interfaces. In

EIGRP, a passive interface does not send or receive routing updates.The Passive Interface table lists each interface configured as a passive interface.

Check the

Enable this EIGRP process

check box.

You can only enable one EIGRP routing process on the device. You must enter an autonomous system number (AS) for the routing process in the EIGRP Process field before you can save your changes.

In the EIGRP Process field, enter the autonomous system (AS) number for the EIGRP process. The AS number can be from 1 to 65535.

(Optional) Click

Advanced

to configure the EIGRP process settings, such as the router ID, default metrics, stub routing settings, neighbor change and warning logging, and the administrative distances for the EIGRP routes.

23-4


OL-20339-01



Step 5

Step 6

Step 7

Step 8

Click the

Networks

tab.

To add a new network entry, click

Add

.

The Add EIGRP Network dialog box appears. To remove a network entry, choose an entry in the table and click

Delete

.

Choose the AS number of the EIGRP routing process from the drop-down list.

Enter the IP address of the networks to participate in the EIGRP routing process in the IP Address field.

Note

To change a network entry, you must first remove the entry and then add a new one. You cannot edit existing entries.

Step 9

Step 10

Enter a network mask to apply to the IP address in the Network Mask field.

Click

OK

.

Enabling EIGRP Stub Routing

You can enable, and configure the adaptive security appliance as an EIGRP stub router. Stub routing decreases memory and processing requirements on the adaptive security appliance. As a stub router, the adaptive security appliance does not need to maintain a complete EIGRP routing table because it forwards all nonlocal traffic to a distribution router. Generally, the distribution router need not send anything more than a default route to the stub router.

Only specified routes are propagated from the stub router to the distribution router. As a stub router, the adaptive security appliance responds to all queries for summaries, connected routes, redistributed static routes, external routes, and internal routes with the message “inaccessible.” When the adaptive security appliance is configured as a stub, it sends a special peer information packet to all neighboring routers to report its status as a stub router. Any neighbor that receives a packet informing it of the stub status will not query the stub router for any routes, and a router that has a stub peer will not query that peer. The stub router depends on the distribution router to send the correct updates to all peers.

To enable the adaptive security appliance as an EIGRP stub routing process, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

On the main ASDM window, choose


.


Check the

Enable EIGRP routing

check box.


Click

Advanced

to configure the EIGRP stub routing process.

The Edit EIGRP Advance Properties dialog box appears.

In the Stub area on the Edit EIGRP Process Advanced Properties dialog box, choose one or more of the

EIGRP stub routing processes. Processes include:

•

•

Stub Receive only—Configures the EIGRP stub routing process to receive route information from the neighbor routers but does not send route information to the neighbors. If this option is selected, you cannot select any of the other stub routing options.

Stub Connected—Advertises connected routes.

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23-5


Customizing EIGRP

Step 6

Step 7

Step 8

Step 9

Step 10

•

•

Stub Static—Advertises static routes.

Stub Redistributed—Advertises redistributed routes.

Stub Summary—Advertises summary routes.

•

Click

OK

.

Click the

Networks

tab.

Click

Add

to add a new network entry.

The

Add EIGRP Network

dialog box appears. To remove a network entry, choose the entry in the table and click

Delete

.



Note


Step 11

Step 12

Enter a network mask to apply to the IP address in the Network Mask field.

Click

OK

.


This section describes how to customize the EIGRP routing and includes the following topics:

•

•

•

•

Defining a Network for an EIGRP Routing Process, page 23-7

Configuring Interfaces for EIGRP, page 23-7

Configuring Passive Interfaces, page 23-8

•

•

Configuring the Summary Aggregate Addresses on Interfaces, page 23-9

Changing the Interface Delay Value, page 23-10

Enabling EIGRP Authentication on an Interface, page 23-10

•

•

•

•

Defining an EIGRP Neighbor, page 23-11

Redistributing Routes Into EIGRP, page 23-12

Filtering Networks in EIGRP, page 23-13

•

•

•

•

Customizing the EIGRP Hello Interval and Hold Time, page 23-15

Disabling Automatic Route Summarization, page 23-15

Configuring Default Information in EIGRP, page 23-16

Disabling EIGRP Split Horizon, page 23-17

Restarting the EIGRP Process, page 23-18

23-6


OL-20339-01



Defining a Network for an EIGRP Routing Process

The Network table lets you specify the networks used by the EIGRP routing process. For an interface to participate in EIGRP routing, it must fall within the range of addresses defined by the network entries.

For directly connected and static networks to be advertised, they must also fall within the range of the network entries.

The Network table displays the networks configured for the EIGRP routing process. Each row of the table displays the network address and associated mask configured for the specified EIGRP routing process.

To add or define a network, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7



.


Check the


check box.

In the

EIGRP Process

field, enter the autonomous system (AS) number for the EIGRP process. The AS number can be from 1 to 65535.

Click the

Networks

tab.

Click

Add


The



Delete

.



Note


Step 8

Step 9

Enter a network mask to apply to the IP address in the

Network Mask

field.

Click

OK

.

Configuring Interfaces for EIGRP

If you have an interface that you do not want to have participate in EIGRP routing, but that is attached to a network that you want advertised, you can configure the adaptive security appliance that covers the network to which the interface is attached, and prevent that interface from sending or receiving EIGRP updates.

To configure interfaces for EIGRP, perform the following steps:

Step 1

Step 2

Step 3



.


Check the


check box.

Click

OK

.

OL-20339-01


23-7



Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Step 12

Step 13

Choose

Configuration > Device Setup > Routing > EIGRP > Interfaces

.

The Interface pane appears and displays the EIGRP interface configurations. The Interface Parameters table displays all of the interfaces on the adaptive security appliance and lets you modify the following settings on a per-interface basis:

•

Authentication key and mode.

•

•

The EIGRP hello interval and hold time.

The interface delay metric used in EIGRP metric calculations.

•

The use of split-horizon on the interface.

Choose an interface entry by double-clicking an interface entry, or choose the entry and click

Edit

.

The Edit EIGRP Interface Entry dialog box appears.

In the

EIGRP Process


In the

Hello Interval

field, enter the interval between EIGRP hello packets sent on an interface.

Valid values are from 1 to 65535 seconds. The default value is 5 seconds.

In the

Hold Time

field, enter the hold time, in seconds. Valid values are from 1 to 65535 seconds. The default value is 15 seconds.

Check the

Enable

check box for Split Horizon.

In the Delay field, enter the delay value. The delay time is in tens of microseconds. Valid values are from

1 to 16777215.

Check the

Enable MD5 Authentication

check box to enable MD5 authentication of EIGRP process messages.

Enter the

Key

or

Key ID

values.

–

Key—Key to authenticate EIGRP updates. The key can contain up to 16 characters.

–

Key ID—Key identification value; valid values range from 1 to 255.

Click

OK

.

Configuring Passive Interfaces

You can configure one or more interfaces as passive interfaces. In EIGRP, a passive interface does not send or receive routing updates.

To configure passive interfaces, perform the following steps:

Note

In ASDM, the Passive Interface table lists each interface configured as a passive interface.

Step 1

Step 2

Step 3

Step 4



.


Check the


check box.

Click

OK

.

Click the

Passive Interfaces

tab.

23-8


OL-20339-01



Step 5

Step 6

Step 7

Step 8

Choose the interface you want to configure from the drop-down list.

Check

Suppress routing updates on all interfaces

check box to specify all interfaces as passive. Even if an interface is not shown in the Passive Interface table, it will be configured as passive when the check box is selected.

Click

Add

to add a passive interface entry.

The

Add EIGRP Passive Interface

dialog box appears. From here you can select the interface you want to make passive in the dialog box. To remove a passive interface, choose the interface in the table and click

Delete

.

Click

OK

.

Configuring the Summary Aggregate Addresses on Interfaces

You can configure a summary addresses on a per-interface basis. You need to manually define summary addresses if you want to create summary addresses that do not occur at a network number boundary or if you want to use summary addresses on a adaptive security appliance with automatic route summarization disabled. If any more specific routes are in the routing table, EIGRP will advertise the summary address out the interface with a metric equal to the minimum of all more specific routes.

To create a summary address, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10



.

The Interface pane displays the EIGRP interface configurations. The Interface Parameters table displays all of the interfaces on the adaptive security appliance and lets you modify the settings on a per-interface basis. For more information on these settings, see

Configuring Interfaces for EIGRP, page 23-7 .

To configure the EIGRP parameters for an interface, double-click an interface entry or select the entry and click

Edit

.

Click

OK

.

Choose

Configuration > Device Setup > Routing > EIGRP > Summary Address

.

The Summary Address pane displays a table of the statically-defined EIGRP summary addresses. By default, EIGRP summarizes subnet routes to the network level. You can create statically-defined EIGRP summary addresses to the subnet level from the Summary Address pane.

Click

Add

to add a new EIGRP summary address, or to click

Edit

to edit an existing EIGRP summary address in the table.

The Add Summary Address or Edit Summary Address dialog box appears. You can also double-click an entry in the table to edit that entry.


In the Interface drop-down list, choose the interface the summary address is advertised from.

In the IP Address field, enter the IP address of the summary route.

In the Netmask field, choose, or enter the network mask to apply to the IP address.

Enter the administrative distance for the route in the Administrative Distance field. If left blank, the route has the default administrative distance of 5.

OL-20339-01


23-9



Step 11

Click

OK

.

Changing the Interface Delay Value

The interface delay value is used in EIGRP distance calculations. You can modify this value on a per-interface basis.

To change the interface delay value, perform the following steps:

Step 1

Step 2

Step 3

Step 4



.

The Interface pane displays the EIGRP interface configurations. The Interface Parameters table displays all of the interfaces on the adaptive security appliance and lets you modify the settings on a per-interface basis. For more information about these settings, see the

“Configuring Interfaces for EIGRP” section on page 23-7 .

Double-click an interface entry or choose the Interface entry and click

Edit

to configure the delay value in the EIGRP parameters for an interface.

The

Edit EIGRP Interface Entry

dialog box appears.

In the

Delay

field, enter the delay value. The delay time is in tens of microseconds. Valid values are from

1 to 16777215.

Click

OK

.

Enabling EIGRP Authentication on an Interface

EIGRP route authentication provides MD5 authentication of routing updates from the EIGRP routing protocol. The MD5 keyed digest in each EIGRP packet prevents the introduction of unauthorized or false routing messages from unapproved sources.

EIGRP route authentication is configured on a per-interface basis. All EIGRP neighbors on interfaces configured for EIGRP message authentication must be configured with the same authentication mode and key for adjacencies to be established.

Note

Before you can enable EIGRP route authentication, you must enable EIGRP.

To enable EIGRP authentication on an interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5



.


Check the


check box.

In the

EIGRP Process


Click the

Networks

tab.

Click

Add


23-10


OL-20339-01



Step 6

Step 7

The



Delete

.


In the

IP Address

field, enter the IP address of the networks to participate in the EIGRP routing process.

Note


Step 8

Step 9

Step 10

Step 11

Step 12

In the

Network Mask

field, choose or enter a network mask to apply to the IP address.

Click

OK

.

Choose


.

The Interface pane displays the EIGRP interface configurations. The Interface Parameters table displays all of the interfaces on the adaptive security appliance and lets you modify the settings on a per-interface

basis. For more information about these settings, see the “Configuring Interfaces for EIGRP” section on page 23-7

.

Check the

Enable MD5 Authentication

check box to enable MD5 authentication of EIGRP process messages. After you check this box, the choices that are enabled are:

–

–

Key—Key to authenticate EIGRP updates. The key can include up to 16 characters.

Key ID—Key identification value; valid values range from 1 to 255.

Click

OK

.

Defining an EIGRP Neighbor

EIGRP hello packets are sent as multicast packets. If an EIGRP neighbor is located across a non broadcast network, such as a tunnel, you must manually define that neighbor. When you manually define an EIGRP neighbor, hello packets are sent to that neighbor as unicast messages.

To manually define an EIGRP neighbor, perform the following steps:

Step 1

Step 2

Step 3

Step 4



.


Check the


check box.

In the

EIGRP Process


Choose

Configuration > Device Setup > Routing > EIGRP > Static Neighbor

.

The Static Neighbor pane appears and displays the statically-defined EIGRP neighbors. An EIGRP neighbor sends EIGRP routing information to and receives EIGRP routing information from the adaptive security appliance. Normally, neighbors are dynamically discovered through the neighbor discovery process. However, on point-to-point, non-broadcast networks, you must statically define the neighbors.

Each row of the Static Neighbor table displays the EIGRP autonomous system number for the neighbor, the neighbor IP address, and the interface through which the neighbor is available.

From the Static Neighbor pane you can add or edit a static neighbor.

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23-11



Step 5

Step 6

Step 7

Step 8

Step 9

Click

Add

or

Edit

to add or edit a EIGRP static neighbor.

The Add or Edit EIGRP Neighbor Entry dialog box appears.

Choose the EIGRP AS number from the drop-down list for the EIGRP process for which the neighbor is being configured.

Choose the Interface Name from the Interface Name drop-down list. This chooses the interface through which the neighbor is available from the list.

Enter the IP address of the neighbor in the Neighbor IP Address field.

Click

OK

.

Redistributing Routes Into EIGRP

You can redistribute routes discovered by RIP and OSPF into the EIGRP routing process. You can also redistribute static and connected routes into the EIGRP routing process. You do not need to redistribute connected routes if they fall within the range of a

network

statement in the EIGRP configuration.

Note

For RIP only: Before you begin this procedure, you must create a route-map to further define which routes from the specified routing protocol are redistributed in to the RIP routing process. See

Chapter 20,

“Defining Route Maps,” for more information about creating a route map.

To redistribute routes into the EIGRP routing process, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8



.

The EIGRP Setup pane is displayed.

Check the


check box.

In the

EIGRP Process

field, enter the autonomous system (AS) number for the EIGRP process. The AS number can range from 1 to 65535.

Choose

Configuration > Device Setup > Routing > EIGRP > Redistribution

.

The Redistribution pane displays the rules for redistributing routes from other routing protocols to the

EIGRP routing process. When redistributing static and connected routes to the EIGRP routing process, metrics are not required to be configured, although this is recommended. Each row of the Redistribution pane table includes a route redistribution entry.

Click

Add

to add a new redistribution rule. If you are editing an existing redistribution rule, go to Step 6.

The Add EIGRP Redistribution Entry dialog box appears.

Choose the address in the table and click

Edit

to edit an existing EIGRP static neighbor, You can also double-click an entry in the table to edit that entry.

The Edit EIGRP Redistribution Entry dialog box appears.

Choose the AS number of the EIGRP routing process to which the entry applies from the drop-down list.

In the Protocol area, click the radio button next to one of the following protocols for the routing process:

•

Static

—Redistributes static routes to the EIGRP routing process. Static routes that fall within the scope of a network statement are automatically redistributed into EIGRP; you do not need to define a redistribution rule for them.

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Step 9

Step 10

Step 11

Step 12

•

•

•

Connected

—Redistributes connected routes into the EIGRP routing process. Connected routes that fall within the scope of a network statement are automatically redistributed into EIGRP; you do not need to define a redistribution rule for them.

RIP

—Redistributes routes discovered by the RIP routing process to EIGRP.

OSPF

—Redistributes routes discovered by the OSPF routing process to EIGRP.

•

In the Optional Metrics area, choose one of the following metrics used for the redistributed route:

•

Bandwidth—EIGRP bandwidth metric in kilobits per second. Valid values range from 1 to

4294967295.

•

Delay—EIGRP delay metric, in 10 microsecond units. Valid values range from 0 to 4294967295.

Reliability—EIGRP reliability metric. Valid values range from 0 to 255, where 255 indicates 100% reliability.

•

•

Loading—EIGRP effective bandwidth (loading) metric. Valid values are from 1 to 255, where 255 indicates 100% loaded.

MTU—The MTU of the path. Valid values are from 1 to 65535.

Choose the route map from the Route Map drop-down list to define which routes are redistributed into the EIGRP routing process. For more details about how to configure a route map, see

Chapter 20,

“Defining Route Maps.”

In the Optional OSPF Redistribution area, click one of the following OSPF radio buttons to further specify which OSPF routes are redistributed into the EIGRP routing process:

•

•

•

Match Internal—Match routes internal to the specified OSPF process.

Match External 1—Match type 1 routes external to the specified OSPF process.

Match External 2—Match type 2 routes external to the specified OSPF process.

Match NSSA-External 1—Match type 1 routes external to the specified OSPF NSSA.

•

•

Match NSSA-External 2—Match type 2 routes external to the specified OSPF NSSA.

Click

OK

.

Filtering Networks in EIGRP

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Note

Before you begin this process, you must create a standard access list that defines the routes that you want to advertise. That is, create a standard access list that defines the routes that you want to filter from sending or receiving updates.

To filter networks in EIGRP, perform the following steps:

Step 1

Step 2

Step 3

Step 4



.


Check the


check box.

In the

EIGRP Process


Choose

Configuration > Device Setup > Routing > EIGRP > Filter Rules

.


23-13



Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Step 12

Step 13

Step 14

Step 15

The Filter Rules pane appears and displays the route filtering rules configured for the EIGRP routing process. Filter rules let you control which routes are accepted or advertised by the EIGRP routing process.

Each row of the Filter Rule table describes a filter rule for a specific interface or routing protocol. For example, a filter rule with a direction of “in” on the outside interface would apply filtering to any EIGRP updates received on the outside interface. A filter rule with a direction of “out” with OSPF 10 specified as the routing protocol would apply the filter rules to routes redistributed into the EIGRP routing process in outbound EIGRP updates.

Click

Add

to add a filter rule. If you are editing an already existing filter rule, skip to Step 6.

The Add Filter Rules dialog box appears.

To edit a filter rule, choose the filter rule in the table and click

Edit

.

The Edit Filter Rules dialog appears. You can also double-click a filter rule to edit the rule. To remove a filter rule, choose the filter rule in the table and click

Delete

.

Choose the autonomous system number (AS) from the drop-down list of the EIGRP routing process to which the entry applies.

Choose the direction from the drop-down list to select the direction of the filter routes.

Choose “

in

” for rules that filter routes from incoming EIGRP routing updates. Choose “

out

” to filter routes from EIGRP routing updates sent by the adaptive security appliance.

If you choose “

out

”, the Routing process field becomes active. Choose the type of route being filtered.

You can filter routes redistributed from static, connected, RIP, and OSPF routing processes. Filters that specify a routing process filter those routes from updates sent on all interfaces.

Enter the OSPF process ID in the ID field.

Click the

Interface

radio button and choose the interface to which the filter applies.

Click

Add

or

Edit

to define an access list for the filter rule.

Choosing Edit opens the Network Rule dialog box for the selected network rule.

The Network Rule dialog box appears.

In the Action drop-down list, choose

Permit

to allow the specified network to be advertised; choose

Deny

to prevent the specified network from being advertised.

In the IP Address field, type IP address of the network being permitted or denied. To permit or deny all addresses, use the IP address

0.0.0.0

with a network mask of

0.0.0.0

.

From the Netmask drop-down list, choose the network mask applied to the network IP address. You can type a network mask into this field or select one of the common masks from the list.

Click

OK

.

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Customizing the EIGRP Hello Interval and Hold Time

The adaptive security appliance periodically sends hello packets to discover neighbors and to learn when neighbors become unreachable or inoperative. By default, hello packets are sent every 5 seconds.

The hello packet advertises the adaptive security appliance hold time. The hold time indicates to EIGRP neighbors the length of time the neighbor should consider the adaptive security appliance reachable. If the neighbor does not receive a hello packet within the advertised hold time, then the adaptive security appliance is considered unreachable. By default, the advertised hold time is 15 seconds (three times the hello interval).

Both the hello interval and the advertised hold time are configured on a per-interface basis. We recommend setting the hold time to be at minimum three times the hello interval.

To configure the hello interval and advertised hold time, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9



.


Check the


check box.

Click

OK

.

Choose


.

The Interface pane appears and displays all of the EIGRP interface configurations.

Double-click an interface entry or choose the entry and click

Edit

.


Choose the EIGRP Autonomous system (AS) number from the drop-down list.

This list is populated from system numbers that were set up when you enabled the EIGRP routing process.

In the Hello Interval field, enter the interval between EIGRP hello packets sent on an interface.


In the Hold Time field, specify the hold time, in seconds.


Click

OK

.

Disabling Automatic Route Summarization

Automatic route summarization is enabled by default. The EIGRP routing process summarizes on network number boundaries. This can cause routing problems if you have noncontiguous networks.

For example, if you have a router with the networks 192.168.1.0, 192.168.2.0, and 192.168.3.0 connected to it, and those networks all participate in EIGRP, the EIGRP routing process creates the summary address 192.168.0.0 for those routes. If an additional router is added to the network with the networks 192.168.10.0 and 192.168.11.0, and those networks participate in EIGRP, they will also be summarized as 192.168.0.0. To prevent the possibility of traffic being routed to the wrong location, you should disable automatic route summarization on the routers creating the conflicting summary addresses.

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23-15



To disable automatic route summarization in ASDM, perform the following steps:

Step 2

Step 3

Step 4

Step 5

Step 6

Step 1



.


Check the


check box.

Click the

Process Instance

tab.

Click

Advanced

.

In the Summary area, uncheck the

Auto-Summary

check box.

Click

OK

.

Note

This setting is enabled by default.

Configuring Default Information in EIGRP

You can control the sending and receiving of default route information in EIGRP updates. By default, default routes are sent and accepted. Configuring the adaptive security appliance to disallow default information to be received causes the candidate default route bit to be blocked on received routes.

Configuring the adaptive security appliance to disallow default information to be sent disables the setting of the default route bit in advertised routes.

In ASDM, the Default Information pane displays a table of rules for controlling the sending and receiving of default route information in EIGRP updates. You can have one “in” and one “out” rule for each EIGRP routing process (only one process is currently supported).

By default, default routes are sent and accepted. To restrict or disable the sending and receiving of default route information, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5



.

The main EIGRP Setup pane appears.

Check the


check box.

Click

OK

.

Do one of the following:

•

•

Click

Add

to create a new entry.

To edit an entry, double-click the entry in the table or select an entry in the table an click

Edit

.

The Add Default Information or Edit Default Information dialog box appears for that entry. The EIGRP autonomous system (AS) number is automatically selected in the EIGRP field.

In the Direction field, choose the direction for the rule. Directions include:

•

• in

—The rule filters default route information from incoming EIGRP updates.

out

—The rule filters default route information from outgoing EIGRP updates.

You can have one “in” rule and one “out” rule for each EIGRP process.

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Step 6

Step 7

Add network rules to the network rule table. The network rules define which networks are allowed and which are not when receiving or sending default route information. Repeat the following steps for each network rule you are adding to the default information filter rule.

a.

b.

c.

Click

Add

to add a network rule. Double-click an existing network rule to edit the rule.

In the Action field, click

Permit

to allow the network or

Deny

to block the network.

Enter the IP address and network mask of the network being permitted or denied by the rule in the

IP Address and Network Mask fields.

To deny all default route information from being accepted or sent, enter

0.0.0.0

as the network address and choose

0.0.0.0

as the network mask.

d.

Click

OK

to add the specified network rule to the default information filter rule.

Click

OK

to accept the default information filter rule.

Disabling EIGRP Split Horizon

Split horizon controls the sending of EIGRP update and query packets. When split horizon is enabled on an interface, update and query packets are not sent for destinations for which this interface is the next hop. Controlling update and query packets in this manner reduces the possibility of routing loops.

By default, split horizon is enabled on all interfaces.

Split horizon blocks route information from being advertised by a router out of any interface from which that information originated. This behavior usually optimizes communications among multiple routing devices, particularly when links are broken. However, with nonbroadcast networks, there may be situations where this behavior is not desired. For these situations, including networks in which you have

EIGRP configured, you may want to disable split horizon.

If you disable split horizon on an interface, you must disable it for all routers and access servers on that interface.

To disable EIGRP split horizon, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5



.

The Interface pane appears and displays the EIGRP interface configurations.


Edit

.




Uncheck the

Split Horizon

check box.

Click

OK

.

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23-17


Monitoring EIGRP

Restarting the EIGRP Process

To restart an EIGRP process or clear redistribution or counters, perform the following steps:

Step 1

Step 2



.


Click

Reset

.

Monitoring EIGRP

You can use the following commands to monitor the EIGRP routing process. For examples and descriptions of the command output, see the


. Additionally, you can disable the logging of neighbor change messages and neighbor warning messages.

To monitor or disable various EIGRP routing statistics, perform the following steps:

Step 1

Step 2


Monitoring > Routing > EIGRP Routing

.

Click the routes that you want to monitor.

Note

By default, neighbor change and neighbor warning messages are logged.

Configuration Example for EIGRP

The following example shows how to enable and configure EIGRP with various optional processes:

Step 2

Step 3

Step 4

Step 5

Step 6

Step 1

Step 7



.


Check the


check box.

Click

OK

.

Click the

Passive Interfaces

tab.

Choose the interface you want to configure from the drop-down list.

Check the

Suppress routing updates on all interfaces

check box to specify all interfaces as passive.

Even if an interface is not shown in the Passive Interface table, it will be configured as passive when this check box is selected.

Click

Add

to add a passive interface entry.

The Add EIGRP Passive Interface dialog box appears. From here you can select the interface you want to make passive in the dialog box. To remove a passive interface, select the interface in the table and click

Delete

.

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OL-20339-01


Configuration Example for EIGRP

Step 8

Step 9

Step 10

Step 11

Step 12

Click

OK

.

Click the

Networks

tab.

Click

Add


The Add EIGRP Network dialog box appears. To remove a network entry, select the entry in the table and click

Delete

.


In the IP Address field, enter the IP address of the networks to participate in the EIGRP routing process.

Note


Step 13

Step 14

Step 15

Step 16

Step 17

Step 18

Step 19

Step 20

Step 21

Step 22

Step 23

Step 24

Step 25

In the Network Mask field, choose or enter a network mask to apply to the IP address.

Click

OK

.

Choose

Configuration > Device Setup > Routing > EIGRP > Static Neighbor

.

Click

Add

to add a static neighbor.

The Add EIGRP Neighbor Entry dialog box appears.

Choose the EIGRP AS number from the drop- down list for which the EIGRP process the neighbor is being configured.

Choose the Interface Name through which the neighbor is available from the Interface Name drop-down list.

Enter the IP address of the neighbor in the Neighbor IP Address field.

Click

OK

.

Choose


.

The Interface pane appears and displays the EIGRP interface configurations.


Edit

.




Enter the delay value in the Delay field. The delay time is in tens of microseconds. Valid values are from

1 to 16777215.

Click

OK

.

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23-19


Feature History for EIGRP


Table 23-1 lists each feature change and the platform release in which it was implemented. ASDM is

backwards-compatible with multiple platform releases, so the specific ASDM release in which support was added is not listed.

Table 23-1 Feature History for EIGRP

Feature Name

EIGRP Support

Platform

Releases

7.0(1)


Support was added for routing data, performing authentication, and redistributing and monitoring routing information using the Enhanced Interior Gateway Routing

Protocol (EIGRP).

The

Configuration > Device Setup > Routing > EIGRP


23-20


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23-21



23-22


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23-23



23-24


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23-25



23-26


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23-28


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23-30


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C H A P T E R

24

Configuring Multicast Routing

This chapter describes how to configure the adaptive security appliance to use the multicast routing protocol and includes the following sections:

•

Information About Multicast Routing, page 24-1

•

•

•

•

•

Licensing Requirements for Multicast Routing, page 24-2


Enabling Multicast Routing, page 24-3

Customizing Multicast Routing, page 24-4

•

•

Configuration Example for Multicast Routing, page 24-17

Additional References, page 24-18

Feature History for Multicast Routing, page 24-19

Information About Multicast Routing

Multicast routing is a bandwidth-conserving technology that reduces traffic by simultaneously delivering a single stream of information to thousands of corporate recipients and homes. Applications that take advantage of multicast routing include videoconferencing, corporate communications, distance learning, and distribution of software, stock quotes, and news.

Multicast routing protocols delivers source traffic to multiple receivers without adding any additional burden on the source or the receivers while using the least network bandwidth of any competing technology. Multicast packets are replicated in the network by Cisco routers enabled with Protocol

Independent Multicast (PIM) and other supporting multicast protocols resulting in the most efficient delivery of data to multiple receivers possible.

The adaptive security appliance supports both stub multicast routing and PIM multicast routing.

However, you cannot configure both concurrently on a single adaptive security appliance.

Note

Only the UDP transport layer is supported for multicast routing.


24-1 OL-20339-01

Chapter 24 Configuring Multicast Routing

Licensing Requirements for Multicast Routing

Stub Multicast Routing

Stub multicast routing provides dynamic host registration and facilitates multicast routing. When configured for stub multicast routing, the adaptive security appliance acts as an IGMP proxy agent.

Instead of fully participating in multicast routing, the adaptive security appliance forwards IGMP messages to an upstream multicast router, which sets up delivery of the multicast data. When configured for stub multicast routing, the adaptive security appliance cannot be configured for PIM.

The adaptive security appliance supports both PIM-SM and bi-directional PIM. PIM-SM is a multicast routing protocol that uses the underlying unicast routing information base or a separate multicast-capable routing information base. It builds unidirectional shared trees rooted at a single

Rendezvous Point per multicast group and optionally creates shortest-path trees per multicast source.

PIM Multicast Routing

Bi-directional PIM is a variant of PIM-SM that builds bi-directional shared trees connecting multicast sources and receivers. Bi-directional trees are built using a DF election process operating on each link of the multicast topology. With the assistance of the DF, multicast data is forwarded from sources to the

Rendezvous Point, and therefore along the shared tree to receivers, without requiring source-specific state. The DF election takes place during Rendezvous Point discovery and provides a default route to the

Rendezvous Point.

Note

If the adaptive security appliance is the PIM RP, use the untranslated outside address of the adaptive security appliance as the RP address.

Multicast Group Concept

Multicast is based on the concept of a group. An arbitrary group of receivers expresses an interest in receiving a particular data stream. This group does not have any physical or geographical boundaries—the hosts can be located anywhere on the Internet. Hosts that are interested in receiving data flowing to a particular group must join the group using IGMP. Hosts must be a member of the group to

receive the data stream. For information about how to configure multicast groups, see the “Configuring a Multicast Group” section on page 24-14 .

Multicast Addresses

Multicast addresses specify an arbitrary group of IP hosts that have joined the group and want to receive traffic sent to this group.

Licensing Requirements for Multicast Routing

Model

All models


Base License.

24-2


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Supported in single context mode. In multiple context mode, unshared interfaces and shared interfaces are not supported.



IPv6 Guidelines


Enabling Multicast Routing

Enabling multicast routing lets you enable multicast routing on the adaptive security appliance. Enabling multicast routing enables IGMP and PIM on all interfaces by default. IGMP is used to learn whether members of a group are present on directly attached subnets. Hosts join multicast groups by sending

IGMP report messages. PIM is used to maintain forwarding tables to forward multicast datagrams.

Note

Only the UDP transport layer is supported for multicast routing.

To enable multicast routing,perform the following steps:

Step 1

Step 2


Configuration > Device Setup > Routing > Multicast

.

In the Multicast pane, check the

Enable Multicast

routing check box.

Checking this check box enables IP multicast routing on the adaptive security appliance. Uncheck this check box to disable IP multicast routing. By default, multicast is disabled. Enabling multicast enables multicast on all interfaces. You can disable multicast on a per-interface basis.

Table 24-1

lists the maximum number of entries for specific multicast tables based on the amount of

RAM on the adaptive security appliance. Once these limits are reached, any new entries are discarded.

Table 24-1 Entry Limits for Multicast Tables

Table

MFIB

IGMP Groups

PIM Routes

16 MB 128 MB 128+ MB

1000 3000 5000

1000 3000 5000

3000 7000 12000

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24-3


Customizing Multicast Routing


This section describes how to customize multicast routing and includes the following topics:

•

Configuring Stub Multicast Routing, page 24-4

•

•

•

•

•

•

Configuring a Static Multicast Route, page 24-4

Configuring IGMP Features, page 24-5

Configuring PIM Features, page 24-10

Configuring a Multicast Group, page 24-14

Configuring a Bidirectional Neighbor Filter, page 24-15

Configuring a Multicast Boundary, page 24-16

Configuring Stub Multicast Routing

Note

Stub multicast routing and PIM are not supported concurrently.

An adaptive security appliance acting as the gateway to the stub area does not need to participate in PIM.

Instead, you can configure it to act as an IGMP proxy agent and forward IGMP messages from hosts connected on one interface to an upstream multicast router on another. To configure the adaptive security appliance as an IGMP proxy agent, forward the host join and leave messages from the stub area interface to an upstream interface.

To forward the host join and leave messages, perform the following steps:

Step 1

Step 2

Step 3

Step 4


Configuration > Device Setup > Routing > Multicast > IGMP

.


Enable Multicast routing

check box.

Choose

MForwarding

.

Double-click the specific interface that you want to forward.

This interface is now enabled to be forwarded. Double-click on the enabled interface to disable a specific interface from being forwarded.

Configuring a Static Multicast Route

Configuring static multicast routes lets you separate multicast traffic from unicast traffic. For example, when a path between a source and destination does not support multicast routing, the solution is to configure two multicast devices with a GRE tunnel between them and to send the multicast packets over the tunnel.

When using PIM, the adaptive security appliance expects to receive packets on the same interface where it sends unicast packets back to the source. In some cases, such as bypassing a route that does not support multicast routing, you may want unicast packets to take one path and multicast packets to take another.

Static multicast routes are not advertised or redistributed.

24-4


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To configure a static multicast route or a static multicast route for a stub area, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5


Configuration > Device Setup > Routing > Multicast > MRoute

.

Choose

Add

or

Edit

.

The Add or Edit Multicast Route dialog box appears.

Use the

Add Multicast Route

dialog box to add a new static multicast route to the adaptive security appliance. Use the

Edit Multicast Route

dialog box to change an existing static multicast route

In the Source Address field enter the IP address of the multicast source. You cannot change this value when editing an exiting static multicast route.

Choose the network mask for the IP address of the multicast source from the from the

Source Mask

drop-down list.

In the Incoming Interface area, click on either the

RPF Interface

radio button to choose RPF to forward the route, or click the

Interface Name

radio button and enter the following:

•

•

In the Source Interface field, choose the incoming interface for the multicast route from the drop-down list.

In the Destination Interface field, choose the destination interface that the route is forwarded through the selected interface form the drop-down list.

Note

You can specify the interface, or the RPF neighbor, but not both at the same time

Step 6

Step 7

In the Administrative Distance field, choose the administrative distance of the static multicast route. If the static multicast route has the same administrative distance as the unicast route, then the static multicast route takes precedence.

Click

OK

.

Configuring IGMP Features

IP hosts use Internet Group Management Protocol, or IGMP, to report their group memberships to directly connected multicast routers.

IGMP is used to dynamically register individual hosts in a multicast group on a particular LAN. Hosts identify group memberships by sending IGMP messages to their local multicast router. Under IGMP, routers listen to IGMP messages and periodically send out queries to discover which groups are active or inactive on a particular subnet.

IGMP uses group addresses (Class D IP address) as group identifiers. Host group address can be in the range 224.0.0.0 to 239.255.255.255. The address 224.0.0.0 is never assigned to any group. The address

224.0.0.1 is assigned to all systems on a subnet. The address 224.0.0.2 is assigned to all routers on a subnet.

When you enable multicast routing on the adaptive security appliance, IGMP Version 2 is automatically enabled on all interfaces.

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24-5



Note

Only the

no igmp

command appears in the interface configuration when you use the

show run

command. If the

multicast-routing

command appears in the device configuration, then IGMP is automatically enabled on all interfaces.

This section describes how to configure optional IGMP setting on a per-interface basis and includes the following topics:

•

•

•

•

Disabling IGMP on an Interface, page 24-6

Configuring IGMP Group Membership, page 24-6

Configuring a Statically Joined IGMP Group, page 24-7

•

•

Controlling Access to Multicast Groups, page 24-8

Limiting the Number of IGMP States on an Interface, page 24-8

Modifying the Query Messages to Multicast Groups, page 24-9

•

Changing the IGMP Version, page 24-9

Disabling IGMP on an Interface

You can disable IGMP on specific interfaces. This is useful if you know that you do not have any multicast hosts on a specific interface and you want to prevent the adaptive security appliance from sending host query messages on that interface.

To disable IGMP on an interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4


Configuration > Device Setup > Routing > Multicast > IGMP >

Protocol

.

The Protocol pane displays the IGMP parameters for each interface on the adaptive security appliance.

Choose the interface that you want to disable and click

Edit

.

To disable the specified interface uncheck the

Enable IGMP

check box.

Click

OK

.

The Protocol pane displays

Yes

if IGMP is enabled on the interface, or

No

if IGMP is disabled on the interface.

Configuring IGMP Group Membership

You can configure the adaptive security appliance to be a member of a multicast group. Configuring the adaptive security appliance to join a multicast group causes upstream routers to maintain multicast routing table information for that group and keep the paths for that group active.

Note

If you want to forward multicast packets for a specific group to an interface without the adaptive security appliance accepting those packets as part of the group, see the

“Configuring a Statically Joined IGMP

Group” section on page 24-7 .

To have the adaptive security appliance join a multicast group,perform the following steps:

24-6


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Step 1

Step 2

Step 3

Step 4

Step 5



Join Group

.

The Join Group pane appears.

Choose

Add

or

Edit

.

The Add IGMP Join Group dialog box allows you to configure an interface to be a member of a multicast group. The Edit IGMP Join Group dialog box to change existing membership information.

In the Interface Name field, choose the interface name from the drop-down list. If you are editing an existing entry, you cannot change this value.

In the Multicast Group Address field, enter the address of a multicast group that the interface belongs to. The group address must be from 224.0.0.0 to 239.255.255.255.

Click

OK

.

Configuring a Statically Joined IGMP Group

Sometimes a group member cannot report its membership in the group because of some configuration, or there may be no members of a group on the network segment. However, you still want multicast traffic for that group to be sent to that network segment. You can have multicast traffic for that group sent to the segment by configuring a statically joined IGMP group.

From ASDM, use the

Configuration > Routing > Multicast > IGMP > Static Group

pane to configure the adaptive security appliance to be a statically connected member of a group. With this method, the adaptive security appliance does not accept the packets itself, but only forwards them. Therefore, this method allows fast switching. The outgoing interface appears in the IGMP cache, but itself is not a member of the multicast group.

To configure a statically joined multicast group on an interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5



Static Group

.

The Static Group pane appears.

Choose

Add

or

Edit

.

Use the Add IGMP Static Group dialog box to statically assign a multicast group to an interface. Use the

Edit IGMP Static Group dialog box to change existing static group assignments.


In the Multicast Group Address field, enter the address of a multicast group that the interface belongs to. The group address must be from 224.0.0.0 to 239.255.255.255.

Click

OK

.

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24-7



Controlling Access to Multicast Groups

To control the multicast groups that hosts on the adaptive security appliance interface can join, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7



Access Group

.

The Access Group pane appears. The table entries in the Access Group pane are processed from the top down. Place more specific entries near the top of the table and more generic entries further down. For example, place an access group entry that permits a specific multicast group near the top of the table and an access group entry below that denies a range of multicast groups, including the group in the permit rule. The group is permitted because the permit rule is enforced before the deny rule.

Double-clicking an entry in the table opens the Add or Edit Access Group dialog box for the selected entry.

Choose

Add

or

Edit

.

The Add Access Group or Edit Access Group dialog box appears. The Add Access Group dialog box lets you add a new access group to the Access Group Table. The Edit Access Group dialog box lets you change information for an existing access group entry. Some fields may be locked when editing existing entries.

Choose the interface name that the access group is associated with from the Interface drop-down list.

You cannot change the associated interface when you are editing an existing access group.

Choose

permit

from the Action drop-down list to allow the multicast group on the selected interface.

Choose

deny

to filter the multicast group from the selected interface.

In the Multicast Group Address field, enter the address of the multicast group to which the access group applies.

Enter the network mask for the multicast group address, or choose one of the common network masks from the Netmask drop-down list.

Click

OK

.

Limiting the Number of IGMP States on an Interface

You can limit the number of IGMP states resulting from IGMP membership reports on a per-interface basis. Membership reports exceeding the configured limits are not entered in the IGMP cache and traffic for the excess membership reports is not forwarded.

To limit the number of IGMP states on an interface,perform the following steps:

Step 1

Step 2

Step 3



Protocol

.

Choose the interface you want to limit from the table on the Protocol pane, and click

Edit

.

The Configure IGMP Parameters dialog box appears.

In the Group Limit field, enter the maximum number of host that can join on an interface. Valid values range from 0 to 500. The default value is 500. Setting this value to 0 prevents learned groups from being added, but manually defined memberships are still permitted.

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Step 4

Click

OK

.

Modifying the Query Messages to Multicast Groups

The adaptive security appliance sends query messages to discover which multicast groups have members on the networks attached to the interfaces. Members respond with IGMP report messages indicating that they want to receive multicast packets for specific groups. Query messages are addressed to the all-systems multicast group, which has an address of 224.0.0.1, with a time-to-live value of 1.

These messages are sent periodically to refresh the membership information stored on the adaptive security appliance. If the adaptive security appliance discovers that there are no local members of a multicast group still attached to an interface, it stops forwarding multicast packet for that group to the attached network and it sends a prune message back to the source of the packets.

By default, the PIM designated router on the subnet is responsible for sending the query messages. By default, they are sent once every 125 seconds.

When changing the query response time, by default, the maximum query response time advertised in

IGMP queries is 10 seconds. If the adaptive security appliance does not receive a response to a host query within this amount of time, it deletes the group.

To change the query interval, query response time, and query timeout value, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5



Protocol

.

Choose the interface you want to limit from the table on the Protocol pane, and click

Edit

.

The Configure IGMP Parameters dialog box appears.

In the Query Interval field, enter the interval, in seconds, at which the designated router sends IGMP host-query messages. Valid values range from 1 to 3600 seconds. The default value is 125 seconds.

If the adaptive security appliance does not hear a query message on an interface for the specified timeout value, then the adaptive security appliance becomes the designated router and starts sending the query messages.

In the Query Timeout field, enter the period of time, in seconds, before which the adaptive security appliance takes over as the requester for the interface after the previous requester has stopped doing so.


Click

OK

.

Changing the IGMP Version

By default, the adaptive security appliance runs IGMP Version 2, which enables several additional features.

All multicast routers on a subnet must support the same version of IGMP. The adaptive security appliance does not automatically detect version 1 routers and switch to version 1. However, a mix of

IGMP Version 1 and 2 hosts on the subnet works; the adaptive security appliance running IGMP Version

2 works correctly when IGMP Version 1 hosts are present.

To control which version of IGMP is running on an interface,perform the following steps:

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24-9



Step 1

Step 2

Step 3

Step 4



Protocol

.

Choose the interface you want to change the version of IGMP from the table on the Protocol pane, and click

Edit

.

The Configure IGMP Interface dialog box appears.

Choose the version number from the Version drop-down list.

Click

OK

.

Configuring PIM Features

Routers use PIM to maintain forwarding tables for forwarding multicast diagrams. When you enable multicast routing on the adaptive security appliance, PIM and IGMP are automatically enabled on all interfaces.

Note

PIM is not supported with PAT. The PIM protocol does not use ports and PAT only works with protocols that use ports.

This section describes how to configure optional PIM settings and includes the following topics:

•

Enabling and Disabling PIM on an Interface, page 24-10

•

Configuring a Static Rendezvous Point Address, page 24-11

•

•

•

•

•

Configuring the Designated Router Priority, page 24-12

Configuring and Filtering PIM Register Messages, page 24-12

Configuring PIM Message Intervals, page 24-13

Configuring a Multicast Boundary, page 24-16

Filtering PIM Neighbors, page 24-14

Enabling and Disabling PIM on an Interface

You can enable or disable PIM on specific interfaces. To enable or disable PIM on an interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4


Configuration > Device Setup > Routing > Multicast > PIM >

Protocol

.

Choose the interface you want to enable for PIM from the table on the Protocol pane, and click

Edit

.

The Edit PIM Protocol dialog box appears.

Check the

Enable PIM

check box.

To disable PIM, uncheck this check box.

Click

OK

.

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Configuring a Static Rendezvous Point Address

All routers within a common PIM sparse mode or bidir domain require knowledge of the PIM RP address. The address is statically configured using the

pim rp-address

command.

Note

The adaptive security appliance does not support Auto-RP or PIM BSR

You can configure the adaptive security appliance to serve as RP to more than one group. The group range specified in the access list determines the PIM RP group mapping. If an access list is not specified, then the RP for the group is applied to the entire multicast group range (224.0.0.0/4).

To configure the address of the PIM PR, perform the following steps:

Note

The adaptive security appliance always advertises the bidirectional capability in the PIM hello messages regardless of the actual bidirectional configuration.

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6



Rendezvous Points

.

Click

Add

or

Edit

.

The Add or Edit Rendezvous Point dialog box appears. The Add Rendezvous Point dialog box lets you add a new entry to the Rendezvous Point table. The Edit Rendezvous Point dialog box lets you change an existing RP entry. Additionally, you can click

Delete

to remove the selected multicast group entry from the table.

There are some restrictions for RPs:

•

You cannot use the same RP address twice.

•

You cannot specify All Groups for more than one RP.

In the Rendezvous Point Address field, type the IP address for the RP.

When editing an existing RP entry, you cannot change this value.

Check the

Use bi-directional forwarding

check box if the specified multicast groups are to operate in bidirectional mode. The Rendezvous Point pane displays

Yes

if the specified multicast groups are to operate in bidirectional mode; the pane displays

No

if the specified groups are to operate in sparse mode.

In bidirectional mode, if the adaptive security appliance receives a multicast packet and has no directly connected members or PIM neighbors present, it sends a Prune message back to the source.

Click the

Use this RP for All Multicast Groups

radio button to use the specified RP for all multicast groups on the interface or click the

Use this RP for the Multicast Groups as specified below

radio button to designate the multicast groups to use with specified RP.

For more information about multicast groups, see the “Configuring a Multicast Group” section on page 24-14

.

Click

OK

.

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24-11



Configuring the Designated Router Priority

The DR is responsible for sending PIM register, join, and prune messaged to the RP. When there is more than one multicast router on a network segment, there is an election process to select the DR based on

DR priority. If multiple devices have the same DR priority, then the device with the highest IP address becomes the DR.

By default, the adaptive security appliance has a DR priority of 1. To change this value, perform the following steps:

Step 1

Step 2

Step 3

Step 4



Protocol

.


Edit

.


In the DR Priority field type the value for the designated router priority for the selected interface. The router with the highest DR priority on subnet becomes the designated router. Valid values range from 0 to 4294967294. The default DR priority is

1

. Setting this value to 0 makes the adaptive security appliance interface ineligible to become the default router.

Click

OK

.

Configuring and Filtering PIM Register Messages

When the adaptive security appliance is acting as an RP, you can restrict specific multicast sources from registering with it. This prevents unauthorized sources from registering with the RP. The Request Filter pane lets you define the multicast sources from which the adaptive security appliance will accept PIM register messages.

To filter PIM register messages, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7



Request Filter

.

Click

Add

.

The Request Filter Entry dialog box lets you define the multicast sources that are allowed to register with the adaptive security appliance when the adaptive security appliance acts as an RP. You create the filter rules based on the source IP address and the destination multicast address.

From the Action drop-down list, choose

Permit

to create a rule that allows the specified source of the specified multicast traffic to register with the adaptive security appliance, or choose

Deny

to create a rule that prevents the specified source of the specified multicast traffic from registering with the adaptive security appliance.

In the Source IP Address field, type the IP address for the source of the register message.

In the Source Netmask field, type or choose the network mask from the drop-down list for the source of the register message.

In the Destination IP Address field, type the multicast destination address.

In the Destination Netmask field, type or choose the network mask from the drop-down list for the multicast destination address.

24-12


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Step 8

Click

OK

.

Configuring PIM Message Intervals

Router query messages are used to select the PIM DR. The PIM DR is responsible for sending router query messages. By default, router query messages are sent every 30 seconds. Additionally, every 60 seconds, the adaptive security appliance sends PIM join/prune messages.

To change these intervals, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5



Protocol

.


Edit

.


In the Hello Interval field, type the frequency, in seconds, at which the interface sends PIM hello messages.

In the Prune Interval field, type the frequency, in seconds, at which the interface sends PIM join and prune advertisements.

Click

OK

.

Configuring a Route Tree

By default, PIM leaf routers join the shortest-path tree immediately after the first packet arrives from a new source. This reduces delay, but requires more memory than shared tree. You can configure whether the adaptive security appliance should join shortest-path tree or use shared tree, either for all multicast groups or only for specific multicast addresses.

To configure a PIM leaf router tree, perform the following steps:

Step 1

Step 2



Route Tree

.

Click one of the following radio buttons:

•

Use Shortest Path Tree for All Groups

—Choose this option to use the shortest-path tree for all multicast groups.

•

•

Use Shared Tree for All Groups

—Choose this option to use the shared tree for all multicast groups.

Use Shared Tree for the Groups specified below

—Choose this option to use the shared tree for the groups specified in the Multicast Groups table. Shortest-path tree is used for any group not specified in the Multicast Groups table.

The Multicast Groups table displays the multicast groups to use Shared Tree with.

The table entries are processed from the top down. You can create an entry that includes a range of multicast groups but excludes specific groups within that range by placing deny rules for the specific groups at the top of the table and the permit rule for the range of multicast groups below the deny statements.

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24-13



To edit a multicast group, see the

“Configuring a Multicast Group” section on page 24-14 .

Configuring a Multicast Group

Multicast groups are lists of access rules that define which multicast addresses are part of the group. A multicast group can contain a single multicast address or a range of multicast addresses. Use the Add

Multicast Group dialog box to create a new multicast group rule. Use the Edit Multicast Group dialog box to modify an existing multicast group rule.

To configure a multicast group, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9



Rendezvous Points

.

The Rendezvous Point pane appears. Click the group that you want to configure.

The Edit Rendezvous Point dialog box appears.

Click the

Use this RP for the Multicast Groups as specified below

radio button to designate the multicast groups to use with specified RP.

Click

Add

or

Edit

.

The Add or Edit Multicast Group dialog box appears.


Permit

to create a group rule that allows the specified multicast addresses, or choose

Deny

to create a group rule that filters the specified multicast addresses.

In the Multicast Group Address field, type the multicast address associated with the group.

From the Netmask drop-down list, choose the network mask for the multicast group address.

Click

OK

.

Filtering PIM Neighbors

You can define the routers that can become PIM neighbors. By filtering the routers that can become PIM neighbors, you can do the following:

•

•

Prevent unauthorized routers from becoming PIM neighbors.

Prevent attached stub routers from participating in PIM.

To define the neighbors that can become a PIM neighbor, perform the following steps:

Step 1

Step 2

Step 3

Step 4



Neighbor Filter

.

Choose the PIM neighbor that you want to configure from the table by clicking

Add

/

Edit

/

Insert

.

The Add/Edit/Insert Neighbor Filter Entry dialog box appears. The Add/Edit/Insert Neighbor Filter

Entry dialog box lets you create the ACL entries for the multicast boundary ACL. You can also delete a selected PIM neighbor from this table.

Choose the interface name from the Interface Name drop-down list.


Permit

or

Deny

for the neighbor filter ACL entry.

24-14


OL-20339-01



Step 5

Step 6

Step 7

Choosing

Permit

allows the multicast group advertisements through the interface. Choosing

Deny

prevents the specified multicast group advertisements from passing through the interface. When a multicast boundary is configured on an interface, all multicast traffic is prevented from passing through the interface unless permitted with a neighbor filter entry.

In the IP Address text field, enter the IP address of the multicast PIM group being permitted or denied.

Valid group addresses are from 224.0.0.0 to 239.255.255.255.255.

From the Netmask drop-down list, choose the netmask for the multicast group address.

Click

OK

.

Configuring a Bidirectional Neighbor Filter

The Bidirectional Neighbor Filter pane shows the PIM bidirectional neighbor filters, if any, that are configured on the adaptive security appliance. A PIM bidirectional neighbor filters is an ACL that defines the neighbor devices that can participate in the DF election. If a PIM bidirectional neighbor filter is not configured for an interface, then there are no restrictions. If a PIM bidirectional neighbor filter is configured, only those neighbors permitted by the ACL can participate in DF election process.

When a PIM bidirectional neighbor filter configuration is applied to the adaptive security appliance, an

ACL appears in the running configuration with the name

interface-name

_multicast, to which the

interface-name

is the name of the interface the multicast boundary filter is applied. If an ACL with that name already exists, a number is appended to the name, for example inside_multicast_1. This ACL defines which devices can become PIM neighbors of the adaptive security appliance.

Bidirectional PIM allows multicast routers to keep reduced state information. All of the multicast routers in a segment must be bidirectionally enabled for bidir to elect a DF.

The PIM bidirectional neighbor filters enable the transition from a sparse-mode-only network to a bidir network by letting you specify the routers that should participate in DF election while still allowing all routers to participate in the sparse-mode domain. The bidir-enabled routers can elect a DF from among themselves, even when there are non-bidir routers on the segment. Multicast boundaries on the non-bidir routers prevent PIM messages and data from the bidir groups from leaking in or out of the bidir subset cloud.

When a PIM bidirectional neighbor filter is enabled, the routers that are permitted by the ACL are considered to be bidirectionally capable. Therefore:

•

•

If a permitted neighbor does not support bidir, the DF election does not occur.

If a denied neighbor supports bidir, then DF election does not occur.

•

If a denied neighbor does not support bidir, the DF election can occur.

To define the neighbors that can become a PIM bidirectional neighbor filter, perform the following steps:

Step 1

Step 2



Bidirectional Neighbor Filter

.

The PIM Bidirectional Neighbor Filter table contains the following entries. Double-click an entry to open the Edit Bidirectional Neighbor Filter Entry dialog box for that entry.

Choose the PIM neighbor that you want to configure from the table, by clicking

Add

/

Edit

/

Insert

.

The Add/Edit/Insert Bidirectional Neighbor Filter Entry dialog box lets you create ACL entries for the

PIM bidirectional neighbor filter ACL

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24-15



Step 3

Step 4

Step 5

Step 6

Step 7

Choose the interface name from the Interface Name drop-down list. Select the interface for which you are configuring the PIM bidirectional neighbor filter ACL entry.

From the Action drop-down list, click

Permit

or

Deny

for the neighbor filter ACL entry.

Choose

Permit

to allow the specified devices to participate in the DF election process. Choose

Deny

to prevent the specified devices from participating in the DF election process.

In the IP Address text field, enter the IP address of the multicast PIM group being permitted or denied.

Valid group addresses are from 224.0.0.0 to 239.255.255.255.255.

From the Netmask drop-down list, choose the netmask for the multicast group address.

Click

OK

.

Configuring a Multicast Boundary

Address scoping defines domain boundaries so that domains with RPs that have the same IP address do not leak into each other. Scoping is performed on the subnet boundaries within large domains and on the boundaries between the domain and the Internet.

You can set up an administratively scoped boundary on an interface for multicast group addresses using

Configuration > Routing > Multicast > MBoundary

in ASDM. IANA has designated the multicast address range 239.0.0.0 to 239.255.255.255 as the administratively scoped addresses. This range of addresses can be reused in domains administered by different organizations. They would be considered local, not globally unique.

A standard ACL defines the range of addresses affected. When a boundary is set up, no multicast data packets are allowed to flow across the boundary from either direction. The boundary allows the same multicast group address to be reused in different administrative domains.

You can configureexamine, and filter Auto-RP discovery and announcement messages at the administratively scoped boundary. Any Auto-RP group range announcements from the Auto-RP packets that are denied by the boundary access control list (ACL) are removed. An Auto-RP group range announcement is permitted and passed by the boundary only if all addresses in the Auto-RP group range are permitted by the boundary ACL. If any address is not permitted, the entire group range is filtered and removed from the Auto-RP message before the Auto-RP message is forwarded.

To configure a multicast boundary, perform the following steps:

Step 1

Step 2


Configuration > Routing > Multicast > MBoundary.

The MBoundary pane lets you configure a multicast boundary for administratively-scoped multicast addresses. A multicast boundary restricts multicast data packet flows and enables reuse of the same multicast group address in different administrative domains. When a multicast boundary is defined on an interface, only the multicast traffic permitted by the filter ACL passes through the interface.

Click

Edit

.

The Edit Boundary Filter dialog box appears and displays the multicast boundary filter ACL. You can add and remove boundary filter ACL entries using this dialog box.

When the boundary filter configuration is applied to the adaptive security appliance, the ACL appears in the running configuration with the name

interface-name

_multicast, where the

interface-name

is the name of the interface the multicast boundary filter is applied to. If an ACL with that name already exists, a number is appended to the name, for example inside_multicast_1.

24-16


OL-20339-01


Configuration Example for Multicast Routing

Step 3

Step 4

Step 5

Choose the interface for which you are configuring the multicast boundary filter ACL from the Interface drop-down list.

Check the

Remove any Auto-RP group range

check box to filter Auto-RP messages from sources denied by the boundary ACL. If unchecked, all Auto-RP messages are passed.

Click

OK

.

Configuration Example for Multicast Routing

The following example shows how to enable and configure multicast routing with various optional processes:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7



.


Enable Multicast

routing check box, and click

Apply

.


Configuration > Device Setup > Routing > Multicast > MRoute

.

Choose

Add

or

Edit

.

The Add or Edit Multicast Route dialog box appears.

Use the Add Multicast Route dialog box to add a new static multicast route to the adaptive security appliance. Use the Edit Multicast Route dialog box to change an existing static multicast route.

In the Source Address field, enter the IP address of the multicast source. You cannot change this value when editing an exiting static multicast route.

Choose the network mask for the IP address of the multicast source from the from the Source Mask drop-down list.

In the Incoming Interface area, click either the

RPF Interface

radio button to choose RPF to forward the route, or click the

Interface Name

radio button and enter the following:

•

•

In the Source Interface field, choose the incoming interface for the multicast route from the drop-down list.

In the Destination Interface field, choose the destination interface that the route is forwarded through the selected interface form the drop-down list.

Note

You can specify the interface, or the RPF neighbor, but not both at the same time

Step 8

Step 9

Step 10

Step 11

In the Administrative Distance field, choose the administrative distance of the static multicast route. If the static multicast route has the same administrative distance as the unicast route, then the static multicast route takes precedence.

Click

OK

.



Join Group

.

The Join Group pane appears.

Choose

Add

or

Edit

.

The Add IGMP Join Group dialog box allows you to configure an interface to be a member of a multicast group. The Edit IGMP Join Group dialog box to change existing membership information.

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24-17


Additional References

Step 12

Step 13

Step 14


In the Multicast Group Address field, enter the address of a multicast group to which the interface belongs. The group address must be from 224.0.0.0 to 239.255.255.255.

Click

OK

.


For additional information related to routing, see the following sections:

•

•

Related Documents, page 24-19

RFCs, page 24-19

24-18


OL-20339-01


Feature History for Multicast Routing

Related Documents

Related Topic Document Title

Technical details about the IGMP and multicast routing standards used for implementing the SMR feature

IETF draft-ietf-idmr-igmp-proxy-01.txt

RFCs

RFC

RFC 2113

RFC 2236

RFC 2362

RFC 2588

Title

IP Router Alert Option

IGMPv2

PIM-SM

IP Multicast and Firewalls


Table 24-2


Table 24-2

Feature Name

Feature History for Multicast Routing

Multicast routing support

Platform

Releases

7.0(1)


Support for multicast route data, perform authentication, redistribute and monitor routing information, using the multicast routing protocol was added.

The



OL-20339-01


24-19



24-20


OL-20339-01



OL-20339-01


24-21



24-22


OL-20339-01



OL-20339-01


24-23



24-24


OL-20339-01

C H A P T E R

25


The IPv6 neighbor discovery process uses ICMPv6 messages and solicited-node multicast addresses to determine the link-layer address of a neighbor on the same network (local link), verify the readability of a neighbor, and keep track of neighboring routers. For information about how to configure IPv6

Neighbor Discovery in ASDM, see the


.

This chapter describes how to enable and configure IPv6 neighbor discovery on the adaptive security appliance and includes the following sections:

•

•

•

Configuring Neighbor Solicitation Messages, page 25-1

Configuring Router Advertisement Messages, page 25-8

Configuring a Static IPv6 Neighbor, page 25-18



•


•

Configuring the Neighbor Reachable Time, page 25-4


•

•

•

•

•

•

Information About Neighbor Solicitation Messages, page 25-2

Licensing Requirements for Neighbor Solicitation Messages, page 25-2

Guidelines and Limitations for the Neighbor Solicitation Message Interval, page 25-3

Default Settings for the Neighbor Solicitation Message Interval, page 25-3


Feature History for the Neighbor Solicitation Message Interval, page 25-4


25-1 OL-20339-01

Chapter 25 Configuring IPv6 Neighbor Discovery


Information About Neighbor Solicitation Messages

Neighbor solicitation messages (ICMPv6 Type 135) are sent on the local link by nodes attempting to discover the link-layer addresses of other nodes on the local link. The neighbor solicitation message is sent to the solicited-node multicast address. The source address in the neighbor solicitation message is the IPv6 address of the node sending the neighbor solicitation message. The neighbor solicitation message also includes the link-layer address of the source node.

After receiving a neighbor solicitation message, the destination node replies by sending a neighbor advertisement message (ICPMv6 Type 136) on the local link. The source address in the neighbor advertisement message is the IPv6 address of the node sending the neighbor advertisement message; the destination address is the IPv6 address of the node that sent the neighbor solicitation message. The data portion of the neighbor advertisement message includes the link-layer address of the node sending the neighbor advertisement message.

After the source node receives the neighbor advertisement, the source node and destination node can communicate.

Figure 25-1

shows the neighbor solicitation and response process.

Figure 25-1 IPv6 Neighbor Discovery—Neighbor Solicitation Message

ICMPv6 Type = 135

Src = A

Dst = solicited-node multicast of B

Data = link-layer address of A

Query = what is your link address?

ICMPv6 Type = 136

Src = B

Dst = A

Data = link-layer address of B

A and B can now exchange packets on this link

Neighbor solicitation messages are also used to verify the reachability of a neighbor after the link-layer address of a neighbor is identified. When a node wants to verifying the reachability of a neighbor, the destination address in a neighbor solicitation message is the unicast address of the neighbor.

Neighbor advertisement messages are also sent when there is a change in the link-layer address of a node on a local link. When there is such a change, the destination address for the neighbor advertisement is the all-nodes multicast address.

Licensing Requirements for Neighbor Solicitation Messages


Model

All models


Base License.

25-2


OL-20339-01



Guidelines and Limitations for the Neighbor Solicitation Message Interval







The interval value is included in all IPv6 router advertisements sent out this interface.

Default Settings for the Neighbor Solicitation Message Interval

Table 25-1

lists the default settings for neighbor solicitation message parameters.

Table 25-1 Default Neighbor Solicitation Messages Parameters

Parameters

value

(transmission interval)

Default

1000 seconds between neighbor solicitation transmissions


You can configure the interval between IPv6 neighbor solicitation retransmissions on an interface. Valid values range from 1000 to 3600000 milliseconds. The default value is 1000 milliseconds. This setting is also sent in router advertisement messages.

To configure the neighbor solicitation message interval, perform the following steps:

Step 3

Step 4

Step 5

Step 6

Step 7

Step 1

Step 2

Choose

Configuration

>

Device Setup

>

Interfaces

.

Choose the interface on which to configure the neighbor solicitation interval. The interface must have been configured with an IPv6 address. See the

“Configuring IPv6 Addresses on an Interface” section on page 25-6


Click

Edit


Click the

IPv6

tab.

In the NS Interval field, enter the time interval.

Click

OK

.

Click

Apply


OL-20339-01


25-3



Feature History for the Neighbor Solicitation Message Interval


Table 25-2 Feature History for Neighbor Solicitation Message Interval

Feature Name

Neighbor solicitation message interval

Releases

7.0(1)



The

ipv6 nd ns-interval

command was introduced.

Configuring the Neighbor Reachable Time

•

•

•


•

Information About Neighbor Reachable Time, page 25-4

•

•

Licensing Requirements for Neighbor Reachable Time, page 25-4

Guidelines and Limitations for Neighbor Reachable Time, page 25-4

Default Settings for the Neighbor Reachable Time, page 25-5

Configuring Neighbor Reachable Time, page 25-5

Feature History for Neighbor Reachable Time, page 25-8

Information About Neighbor Reachable Time

The neighbor reachable time enables detecting unavailable neighbors. Shorter configured times enable detecting unavailable neighbors more quickly, however, shorter times consume more IPv6 network bandwidth and processing resources in all IPv6 network devices. Very short configured times are not recommended in normal IPv6 operation.

Licensing Requirements for Neighbor Reachable Time


Model

All models


Base License.

Guidelines and Limitations for Neighbor Reachable Time






25-4


OL-20339-01




•

The interval value is included in all IPv6 router advertisements sent out this interface.

•

The configured time enables detecting unavailable neighbors. Shorter configured times enable detecting unavailable neighbors more quickly; however, shorter times consume more IPv6 network bandwidth and processing resources in all IPv6 network devices. Very short configured times are not recommended in normal IPv6 operation.

Default Settings for the Neighbor Reachable Time

Table 25-3

lists the default settings for neighbor reachable time parameters.

Table 25-3 Default Neighbor Reachable Time Parameters

Parameters

value

(time mode is reachable)

Default

The default is 0.

Configuring Neighbor Reachable Time

The neighbor reachable time enables detecting unavailable neighbors. Shorter configured times enable detecting unavailable neighbors more quickly; however, shorter times consume more IPv6 network bandwidth and processing resources in all IPv6 network devices. Very short configured times are not recommended in normal IPv6 operation.

Valid time values range from 0 to 3600000 milliseconds. The default is 0; however, when you use 0, the reachable time is sent as undetermined. It is up to the receiving devices to set and track the reachable time value.

To configure the amount of time that a remote IPv6 node is considered reachable after a reachability confirmation event has occurred, perform the following steps:

Step 3

Step 4

Step 5

Step 6

Step 7

Step 1

Step 2

Choose

Configuration

>

Device Setup

>

Interfaces

.

Choose the interface for which you want to configure the time. The interface must have been configured with an IPv6 address. For more information, see the


Click

Edit


Click the

IPv6

tab.

In the Reachable Time field, enter a valid value.

Click

OK

.

Click

Apply



Duplicate Address Detection (DAD) settings are part of the Neighbor Discovery configuration. DAD verifies the uniqueness of new unicast IPv6 addresses before they are assigned and ensures that duplicate

IPv6 addresses are detected in the network on a link basis.

To specify DAD settings on the interface, perform the following steps:

OL-20339-01


25-5



Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Enter the number of allowed DAD attempts. This setting configures the number of consecutive neighbor solicitation messages that are sent on an interface while DAD is performed on IPv6 addresses. Valid values are from 0 to 600. A zero value disables DAD processing on the specified interface. The default is one message.

Enter the neighbor solicitation message interval. The neighbor solicitation message requests the link-layer address of a target node. Valid values are from 1000 to 3600000 milliseconds. The default is

1000 milliseconds.

Enter the amount of time in seconds that a remote IPv6 node is considered reachable after a reachability confirmation event has occurred. Valid values are from 1000 to 3600000 milliseconds. The default is zero. A configured time enables the detection of unavailable neighbors. Shorter times enable detection more quickly; however, very short configured times are not recommended in normal IPv6 operation.

Enter the amount of time that IPv6 router advertisement transmissions are considered valid. Valid values are from 3 to 1800 seconds. The default is 200 seconds. Router advertisement transmissions include a preference level and a lifetime field for each advertised router address. These transmissions provide route information and indicate that the router is still operational to network hosts. By default, these transmissions are sent every 400 to 600 seconds.

Enter the interval between IPv6 router advertisement transmissions. Valid values are from 3 to 1800 seconds. The default is 200 seconds. To have the router advertisement transmission interval be listed in milliseconds, check the


check box.

To allow the generation of addresses for hosts, make sure that the Suppress RA check box is unchecked.

This is the default setting if IPv6 unicast routing is enabled. To prevent the generation of IPv6 router advertisement transmissions, check the

Suppress RA

check box.



Configuring IPv6 Addresses on an Interface

To configure IPv6 addresses on an interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

If you have not configured any IPv6 addresses with the CLI, to enable IPv6 addressing, check the

Enable

IPv6

check box.

To make sure that the source addresses of IPv6 packets received on that interface are verified according to the source MAC addresses to ensure that the interface identifiers use the modified EUI-64 format, check the

Enforce EUI-64

check box. If the interface identifiers do not conform to the modified EUI-64 format, an error message appears.

If you are not going to assign any other IPv6 addresses, to set the link-local address manually, enter an address in the Link-local address field. A link-local address should start with FE8, FE9, FEA, or FEB, for example fe80::20d:88ff:feee:6a82.

Alternatively, click the ellipsis to choose a link-local address from the Browse Link-local address dialog box.

After you have selected the link-local address, click

OK

to return to the IPv6 tab.

The selected link-local address appears in the Link-local address field.

To enable address autoconfiguration, check the


check box. During the stateless autoconfiguration process, duplicate address detection (DAD) verifies the uniqueness of new unicast IPv6 addresses before the addresses are assigned to interfaces (the new addresses remain in a tentative state while duplicate address detection is performed). Duplicate address detection is

25-6


OL-20339-01



Step 6

Step 7

Step 8

performed first on the new link-local address. When the link local address is verified as unique, then duplicate address detection is performed all the other IPv6 unicast addresses on the interface. For more information about DAD, see the

“Configuring DAD Settings” section on page 25-5 .


Add

.



EUI-64

check box.

Click

OK


The Interface IPv6 Addresses Address field appears with the modified EUI-64 address.

Step 9

Note

You cannot use IPv6 addresses for the failover LAN and state links. For more information, see

the “Configuring Failover with the High Availability and Scalability Wizard” section on page 58-2

.


“Configuring IPv6 Prefixes on an Interface” section on page 25-7

.

Configuring IPv6 Prefixes on an Interface


Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8


Add

.








check box.

(Optional) The

Off Link





a.

b.








a.


b.


Click

OK


OL-20339-01


25-7




Feature History for Neighbor Reachable Time


Table 25-4 Feature History for Neighbor Reachable Time

Feature Name

Neighbor solicitation message interval

Releases

7.0(1)




An adaptive security appliance can participate in router advertisements so that neighboring devices can dynamically learn a default router address.


•

Information About Router Advertisement Messages, page 25-8

•

•



•

•

Configuring the IPv6 Prefix, page 25-14


Information About Router Advertisement Messages

An adaptive security appliance can participate in router advertisements so that neighboring devices can dynamically learn a default router address. Router advertisement messages (ICMPv6 Type 134) are periodically sent out each IPv6 configured interface of the adaptive security appliance. The router advertisement messages are sent to the all-nodes multicast address.

Figure 25-2 IPv6 Neighbor Discovery—Router Advertisement Message



Router advertisement packet definitions:

ICMPv6 Type = 134

Src = router link-local address

Dst = all-nodes multicast address

Data = options, prefix, lifetime, autoconfig flag

25-8


OL-20339-01



Router advertisement messages typically include the following information:

•

•

•

One or more IPv6 prefix that nodes on the local link can use to automatically configure their IPv6 addresses.

Lifetime information for each prefix included in the advertisement.

•

Sets of flags that indicate the type of autoconfiguration (stateless or stateful) that can be completed.

Default router information (whether the router sending the advertisement should be used as a default router and, if so, the amount of time (in seconds) the router should be used as a default router).

•

•

Additional information for hosts, such as the hop limit and MTU a host should use in packets that it originates.

The amount of time between neighbor solicitation message retransmissions on a given link.

•

The amount of time a node considers a neighbor reachable.

Router advertisements are also sent in response to router solicitation messages (ICMPv6 Type 133).

Router solicitation messages are sent by hosts at system startup so that the host can immediately autoconfigure without needing to wait for the next scheduled router advertisement message. Because router solicitation messages are usually sent by hosts at system startup, and the host does not have a configured unicast address, the source address in router solicitation messages is usually the unspecified

IPv6 address (0:0:0:0:0:0:0:0). If the host has a configured unicast address, the unicast address of the interface sending the router solicitation message is used as the source address in the message. The destination address in router solicitation messages is the all-routers multicast address with a scope of the link. When a router advertisement is sent in response to a router solicitation, the destination address in the router advertisement message is the unicast address of the source of the router solicitation message.

You can configure the following settings for router advertisement messages:

•

The time interval between periodic router advertisement messages.

•

•

The router lifetime value, which indicates the amount of time IPv6 nodes should consider the adaptive security appliance to be the default router.

The IPv6 network prefixes in use on the link.

•

Whether or not an interface transmits router advertisement messages.

Unless otherwise noted, the router advertisement message settings are specific to an interface and are entered in interface configuration mode. See the following topics for information about changing these settings:

•

•

•

•



Configuring the IPv6 Prefix, page 25-14


OL-20339-01


25-9



Configuring the Router Advertisement Transmission Interval

This section shows how to configure the interval between IPv6 router advertisement transmissions on an interface and includes the following topics:

•

Licensing Requirements for Router Advertisement Transmission Interval, page 25-10

•

•

•

•

Guidelines and Limitations for the Router Advertisement Transmission Interval, page 25-10

Default Settings for Router Advertisement Transmission Interval, page 25-10

Configuring Router Advertisement Transmission Interval, page 25-11

Feature History for the Router Advertisement Transmission Interval, page 25-11

Licensing Requirements for Router Advertisement Transmission Interval


Model

All models


Base License.

Guidelines and Limitations for the Router Advertisement Transmission Interval







The interval between transmissions should be less than or equal to the IPv6 router advertisement lifetime if the adaptive security appliance is configured as a default router. To prevent synchronization with other

IPv6 nodes, randomly adjust the actual value used to within 20 percent of the specified value.

Default Settings for Router Advertisement Transmission Interval

Table 25-5 lists the default settings for neighbor reachable time parameters.

Table 25-5 Default Router Advertisement Transmission Interval Parameters

Parameters

value

(interval between transmissions)

Default

The default is 200 seconds.

25-10


OL-20339-01



Configuring Router Advertisement Transmission Interval

By default, router advertisements are sent out every 200 seconds. Valid values range from 3 to 1800 seconds.

The interval between transmissions should be less than or equal to the IPv6 router advertisement lifetime if the adaptive security appliance is configured as a default router. For more information, see the

“Configuring the Router Lifetime Value” section on page 25-12

. To prevent synchronization with other

IPv6 nodes, randomly adjust the actual value used to within 20 percent of the desired value.

To change the interval between router advertisement transmissions on an interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Choose

Configuration

>

Device Setup

>

Interfaces

.

Select the interface for which you want to configure the time.

The interface must have been configured with an IPv6 address. For more information, see the


Click

Edit


Click the

IPv6

tab.

In the RA Interval field, enter a valid transmission interval value.

Note

(Optional) To add a router advertisement transmission interval value in milliseconds instead, check the


check box, and enter a value from 500 to 1800000.

Step 6

Step 7

Click

OK

.

Click

Apply


Feature History for the Router Advertisement Transmission Interval

Table 25-6


Table 25-6 Feature History for Router Advertisement Transmission Interval

Feature Name

Router advertisement transmission interval

Releases

7.0(1)



OL-20339-01


25-11




This section shows how to configure the interval between IPv6 router advertisement transmissions on an interface and includes the following topics:

•

Licensing Requirements for the Router Lifetime Value, page 25-12

•

•

•

•

Guidelines and Limitations for the Router Lifetime Value, page 25-12

Default Settings for the Router Lifetime Value, page 25-12


Feature History for the Router Lifetime Value, page 25-13

Licensing Requirements for the Router Lifetime Value


Model

All models


Base License.

Guidelines and Limitations for the Router Lifetime Value







The interval between transmissions should be less than or equal to the IPv6 router advertisement lifetime if the adaptive security appliance is configured as a default router. To prevent synchronization with other

IPv6 nodes, randomly adjust the actual value used to within 20 percent of the specified value.

Default Settings for the Router Lifetime Value


Table 25-7 Default Router Advertisement Transmission Interval Parameters

Parameters

value

(interval between transmissions)

Default

The default is 200 seconds.

25-12


OL-20339-01




The router lifetime value specifies how long nodes on the local link should consider the adaptive security appliance as the default router on the link. Valid values range from 0 to 9000 seconds. The default is

1800 seconds. Entering 0 indicates that the adaptive security appliance should not be considered a default router on the selected interface.

To configure the router lifetime value in IPv6 router advertisements on an interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Choose

Configuration

>

Device Setup

>

Interfaces

.

Select the interface for which you want to configure the lifetime value.

The interface must have been configured with an IPv6 address. For more information see the


Click

Edit

.


Click the

IPv6

tab.

In the RA Lifetime field, enter a valid lifetime value.

Click

OK

.

Click

Apply


Feature History for the Router Lifetime Value

Table 25-8


Table 25-8 Feature History for Router Advertisement Transmission Interval

Feature Name

Router advertisement transmission interval

Releases

7.0(1)



OL-20339-01


25-13



Configuring the IPv6 Prefix

Stateless autoconfiguration uses IPv6 prefixes provided in router advertisement messages to create the global unicast address from the link-local address. The prefix advertisement can be used by neighboring devices to autoconfigure their interface addresses. You can configure which IPv6 prefixes ar e included in IPv6 router advertisements.

This section shows how to configure IPv6 prefixes and includes the following topics:

•

•

•

•

Licensing Requirements for IPv6 Prefixes, page 25-14

Guidelines and Limitations for IPv6 Prefixes, page 25-14

Default Settings for IPv6 Prefixes, page 25-15

Configuring IPv6 Prefixes, page 25-15

Licensing Requirements for IPv6 Prefixes


Model

All models


Base License.

Guidelines and Limitations for IPv6 Prefixes






25-14


OL-20339-01




A date can be set to specify the expiration of a prefix. The valid and preferred lifetimes are counted down in real time. When the expiration date is reached, the prefix will no longer be advertised.

When onlink is on (by default), the specified prefix is assigned to the link. Nodes sending traffic to such addresses that contain the specified prefix consider the destination to be locally reachable on the link.

When autoconfig is on (by default), it indicates to hosts on the local link that the specified prefix can be used for IPv6 autoconfiguration.

For stateless autoconfiguration to work correctly, the advertised prefix length in router advertisement messages must always be 64 bits.

Default Settings for IPv6 Prefixes

Table 25-9

lists the default settings for neighbor reachable time parameters.

Table 25-9

Parameters

prefix lifetime

Default for IPv6 Prefixes Parameters

on-link flag autoconfig flag

Default

The default lifetime is 2592000 seconds (30 days) and a preferred lifetime is 604800 seconds (7 days).

The flag is on by default, which means that the prefix is used on the advertising interface.

The flag is on by default, which means that the prefix is used for autoconfiguration.

Configuring IPv6 Prefixes


Step 1

Step 2

Step 3

Step 4

Step 5

Step 6


Add

.








check box.

(Optional) The

Off Link





a.



OL-20339-01


25-15



Step 7

Step 8 b.






a.


b.


Click

OK




By default, router advertisement messages are automatically sent in response to router solicitation messages. You may want to disable these messages on any interface for which you do not want the adaptive security appliance to supply the IPv6 prefix (for example, the outside interface).

This section shows how to suppress IPv6 router advertisement transmissions on an interface and includes the following topics:

•

Licensing Requirements for Suppressing Router Advertisement Messages, page 25-16

•

•

•

•

Guidelines and Limitations for Suppressing Router Advertisement Messages, page 25-16

Default Settings for Suppressing Router Advertisement Messages, page 25-17


Feature History for Suppressing Router Advertisement Messages, page 25-17

Licensing Requirements for Suppressing Router Advertisement Messages


Model

All models


Base License.

Guidelines and Limitations for Suppressing Router Advertisement Messages






25-16


OL-20339-01




The router lifetime value is included in all IPv6 router advertisements sent out the interface. The value indicates the usefulness of the adaptive security appliance as a default router on this interface.

Setting the value to a non-zero value indicates that the adaptive security appliance should be considered a default router on this interface. The no-zero value for the router lifetime value should not be less than the router advertisement interval.

Default Settings for Suppressing Router Advertisement Messages


Table 25-10

Parameters

router lifetime

Default for Suppressing Router Advertisement Parameters

Default

The default lifetime is 1800 seconds. Setting the value to 0 indicates that the adaptive security appliance should not be considered a default router on this interface.


To suppress IPv6 router advertisement transmissions on an interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Choose

Configuration

>

Device Setup

>

Interfaces

.

Select the interface for which you want to configure the lifetime value. The interface must have been configured with an IPv6 address. For more information, see the

“Configuring IPv6 Addresses on an

Interface” section on page 25-6

.

Click

Edit

.


Click the

IPv6

tab.

Check the

Suppress RA

check box.

Verify that the router advertisement message is suppressed on the interface that is configured for the IPv6 address.

Feature History for Suppressing Router Advertisement Messages


Table 25-11 Feature History for Suppressing Router Advertisement Messages

Feature Name

Suppressing router advertisement messages

Releases

7.0(1)



The

ipv6 nd ra-lifetime

command was introduced.

OL-20339-01


25-17


Configuring a Static IPv6 Neighbor



•

Information About a Static IPv6 Neighbor, page 25-18

•

•

•

•

•

Licensing Requirements for Static IPv6 Neighbor, page 25-18



Configuring a Static IPv6 Neighbor, page 25-19

Feature History for Configuring a Static IPv6 Neighbor, page 25-20

Information About a Static IPv6 Neighbor

You can manually define a neighbor in the IPv6 neighbor cache. If an entry for the specified IPv6 address already exists in the neighbor discovery cache—learned through the IPv6 neighbor discovery process—the entry is automatically converted to a static entry. Static entries in the IPv6 neighbor discovery cache are not modified by the neighbor discovery process

Licensing Requirements for Static IPv6 Neighbor


Model

All models


Base License.








Table 25-12

lists the default settings for static IPv6 neighbor parameters.

Table 25-12 Default Static IPv6 Neighbor Parameters

Parameters

Static IPv6 neighbor

Default

Static entries are not configured in the IPv6 neighbor discovery cache.

25-18


OL-20339-01




Make sure that IPv6 is enabled on at least one interface before trying to add a neighbor, or ASDM returns an error message indicating that the configuration failed. For information about configuring IPv6 on an

interface, see the “Configuring IPv6 Addresses on an Interface” section on page 25-6

.

To add an IPv6 static neighbor, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Choose

Configuration

>


>

Advanced

>


.

Click

Add

.

The Add IPv6 Static Neighbor dialog box appears.

From the Interface Name drop-down list, choose an interface on which to add the neighbor.

In the IP Address field, enter the IPv6 address that corresponds to the local data-link address, or click the ellipsis (...) to browse for an address.

If an entry for the specified IPv6 address already exists in the neighbor discovery cache—learned through the IPv6 neighbor discovery process—the entry is automatically converted to a static entry.

In the MAC address field, enter the local data-line (hardware) MAC address.

Click

OK

.

Note

Before you apply the changes and save the configuration, you can click

Reset

to cancel any changes and restore the original values.

Step 7

Click

Apply


Editing Static Neighbors

To edit a static neighbor that is defined in your configuration, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Choose

Configuration

>


>

Advanced

>


.

Select the neighbor from the main pane, and click

Edit

.

The Edit IPv6 Static Neighbor dialog box appears.

Enter all necessary changes, and click

OK

.

Click

Apply


Deleting Static Neighbors

To delete a static neighbor from your configuration, perform the following steps:

Step 1

Step 2

Choose

Configuration

>


>

Advanced

>


.

Select the neighbor to delete from the main pane, and click

Delete

.

OL-20339-01


25-19


Step 3

The selected neighbor is removed from the list.

Click

Apply

to save the change to your current configuration.


Note

Before you apply the changes and permanently delete the neighbor from your configuration, you can click

Reset

to restore the original values.

Feature History for Configuring a Static IPv6 Neighbor

Table 25-13

Table 25-13


Feature History for Configuring a Static IPv6 Neighbor

Feature Name

Static IPv6 Neighbor

Releases

7.0(1)



25-20


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OL-20339-01


25-21



25-22


OL-20339-01

P

A R T

5

Configuring Network Address Translation

Information About NAT

C H A P T E R

26

This chapter provides an overview of how Network Address Translation (NAT) works on the adaptive security appliance. This chapter includes the following sections:

•

Why Use NAT?, page 26-1

•

•

•

•

•

NAT Terminology, page 26-2

NAT Types, page 26-2

NAT in Routed and Transparent Mode, page 26-12

How NAT is Implemented, page 26-15

•

•

•

NAT Rule Order, page 26-19

Mapped Address Guidelines, page 26-20

DNS and NAT, page 26-21

Where to Go Next, page 26-23

Note

To start configuring NAT, see

Chapter 27, “Configuring Network Object NAT,”

or

Chapter 28,

“Configuring Twice NAT.”

Why Use NAT?

Each computer and device within an IP network is assigned a unique IP address that identifies the host.

Because of a shortage of public IPv4 addresses, most of these IP addresses are private, not routable anywhere outside of the private company network. RFC 1918 defines the private IP addresses you can use internally (

Table 26-1 ):

Table 26-1 Private IP Addresses

Network Class Address Block

Class A addresses 10.0.0.0/8

Class B addresses 172.16.0.0/12

Class C addresses 192.168.0.0/16

Starting Address Ending Address

10.0.0.0

10.255.255.255

172.16.0.0

192.168.0.0

172.31.255.255

Approximate Hosts

16,000,000

1,000,000

192.168.255.255

65,000


26-1 OL-20339-01

NAT Terminology

Chapter 26 Information About NAT

One of the main functions of NAT is to enable private IP networks to connect to the Internet. NAT replaces a private IP address with a public IP address, translating the private addresses in the internal private network into legal, routable addresses that can be used on the public Internet. In this way, NAT conserves public addresses because it can be configured to advertise only one public address for the entire network to the outside world.

Other functions of NAT include:

•

Security—Keeping internal IP addresses hidden discourages direct attacks.

•

•

IP routing solutions—Overlapping IP addresses are not a problem when you use NAT.

Flexibility—You can change internal IP addressing schemes without affecting the public addresses available externally; for example, for a server accessible to the Internet, you can maintain a fixed IP address for Internet use, but internally, you can change the server address.

NAT Terminology

This document uses the following terminology:

•

•

Real address/host/network/interface—The real address is the address that is defined on the host, before it is translated. In a typical NAT scenario where you want to translate the inside network when it accesses the outside, then the inside network would be the “real” network. Note that you can translate any network connected to the adaptive security appliance, not just an inside network,

Therefore if you configure NAT to translate outside addresses, “real” can refer to the outside network when it accesses the inside network.

Mapped address/host/network/interface—The mapped address is the address that the real address is translated to. In a typical NAT scenario where you want to translate the inside network when it accesses the outside, then the outside network would be the “mapped” network.

•

•

Bidirectional initiation—Static NAT allows connections to be initiated

bidirectionally

, meaning both to the host and from the host.

Source and destination NAT—For any given packet, both the source and destination IP addresses are compared to the NAT rules, and one or both can be translated/untranslated.

NAT Types

You can implement NAT using the following methods:

•

•

Static NAT—A consistent mapping between a real and mapped IP address. Allows bidirectional traffic initiation.

Dynamic NAT—A group of real IP addresses are mapped to a (usually smaller) group of mapped IP addresses, on a first come, first served basis. Only the real host can initiate traffic.

•

•

Dynamic Port Address Translation (PAT)—A group of real IP addresses are mapped to a single IP address using a unique source port of that IP address.

Identity NAT—Static NAT lets you translate a real address to itself, essentially bypassing NAT. You might want to configure NAT this way when you want to translate a large group of addresses, but then want to exempt a smaller subset of addresses.

26-2


OL-20339-01



•

•

•

•

Static NAT, page 26-3

Dynamic NAT, page 26-8

Dynamic PAT, page 26-10

Identity NAT, page 26-11

NAT Types

Static NAT

This section describes static NAT and includes the following topics:

•

Information About Static NAT, page 26-3

•

•

•

Information About Static NAT with Port Translation, page 26-3

Information About One-to-Many Static NAT, page 26-6

Information About Other Mapping Scenarios (Not Recommended), page 26-7

Information About Static NAT

Static NAT creates a fixed translation of a real address to a mapped address. Because the mapped address is the same for each consecutive connection, static NAT allows bidirectional connection initiation, both to and from the host (if an access rule exists that allows it). With dynamic NAT and PAT, on the other hand, each host uses a different address or port for each subsequent translation, so bidirectional initiation is not supported.

Figure 26-1 shows a typical static NAT scenario. The translation is always active so both real and remote

hosts can initiate connections.

Figure 26-1 Static NAT

Security

Appliance

10.1.1.1

209.165.201.1

10.1.1.2

209.165.201.2

Inside Outside

Information About Static NAT with Port Translation

Static NAT with port translation lets you specify a real and mapped protocol (TCP or UDP) and port.


•

Information About Static NAT with Port Address Translation, page 26-4

•

•

•

Static NAT with Identity Port Translation, page 26-5

Static NAT with Port Translation for Non-Standard Ports, page 26-5

Static Interface NAT with Port Translation, page 26-5

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NAT Types

Information About Static NAT with Port Address Translation

When you specify the port with static NAT, you can choose to map the port to the same value or to a different value. Using the same value lets you translate ipA/port1 to ipX/port1 while translating ipA/port2 to ipY/port2.

Figure 26-2

shows a typical static NAT with port translation scenario showing both a port that is mapped to itself and a port that is mapped to a different value. The translation is always active so both translated and remote hosts can initiate connections.

Figure 26-2 Typical Static NAT with Port Translation Scenario

Security

Appliance

10.1.1.1:2 3 209.165.201.1:2 3

10.1.1.2: 8 0 8 0 209.165.201.2: 8 0

Inside Outside

Note

For applications that require application inspection for secondary channels (for example, FTP and VoIP), the adaptive security appliance automatically translates the secondary ports.

26-4


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NAT Types

Static NAT with Identity Port Translation

The following static NAT with port translation example provides a single address for remote users to access FTP, HTTP, and SMTP. These servers are actually different devices on the real network, but for each server, you can specify static NAT with port translation rules that use the same mapped IP address, but different ports. (See

Figure 26-3 . See the

“Single Address for FTP, HTTP, and SMTP (Static NAT with Port Translation)” section on page 27-29 for details on how to configure this example.)

Figure 26-3 Static NAT with Port Translation

Host

Undo Translation

209.165.201.

3 :21 10.1.2.27

Outside

Undo Translation

209.165.201.

3 :25 10.1.2.29

Undo Translation

209.165.201.

3 : 8 0 10.1.2.2

8

Inside

FTP server

10.1.2.27

SMTP server

HTTP server

10.1.2.2

8

10.1.2.29

Static NAT with Port Translation for Non-Standard Ports

You can also use static NAT with port translation to translate a well-known port to a non-standard port or vice versa. For example, if inside web servers use port 8080, you can allow outside users to connect to port 80, and then undo translation to the original port 8080. Similarly, to provide extra security, you can tell web users to connect to non-standard port 6785, and then undo translation to port 80.

Static Interface NAT with Port Translation

You can configure static NAT to map a real address to an interface address/port combination. For example, if you want to redirect Telnet access to the adaptive security appliance outside port to an inside

IP address (for example, a router interface), then you can map the inside IP address on port 23 to the interface address on port 23. (Note that Telnet is not allowed to the lowest security interface normally; static NAT with interface port translation redirects the disallowed Telnet session instead of denying it).

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NAT Types

Information About One-to-Many Static NAT

Typically, you configure static NAT with a one-to-one mapping. However, in some cases, you might want to configure a single real address to several mapped addresses (one-to-many). When you configure one-to-many static NAT, when the real host initiates traffic, it always uses the first mapped address.

However, for traffic initiated to the host, you can initiate traffic to any of the mapped addresses, and they will be untranslated to the single real address.

Figure 26-4

shows a typical one-to-many static NAT scenario. The first translation is always active so both translated and remote hosts can initiate connections, but the subsequent mappings are unidirectional to the real host.

Figure 26-4 One-to-Many Static NAT

Security

Appliance

10.1.2.27

10.1.2.27

10.1.2.27

209.165.201.

3

209.165.201.4

209.165.201.5

Inside Outside

26-6


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NAT Types

For example, you have a load balancer at 10.1.2.27; depending on the URL requested, it redirects traffic to the correct web server. (See

Figure 26-5

. See the

“Inside Load Balancer with Multiple Mapped

Addresses (Static NAT, One-to-Many)” section on page 27-25

for details on how to configure this example.)

Figure 26-5 One-to-Many Static NAT

Host

Undo Translation

209.165.201.

3 10.1.2.27

Outside Undo Translation

209.165.201.5

10.1.2.27

Undo Translation

209.165.201.4

10.1.2.27

Inside

Load Balancer

10.1.2.27

Web Servers

Information About Other Mapping Scenarios (Not Recommended)

The adaptive security appliance has the flexibility to allow any kind of static mapping scenario: one-to-one, one-to-many, but also few-to-many, many-to-few, and many-to-one mappings. These other mapping options, however, might result in unintended consequences. We recommend using only one-to-one or one-to-many mappings.

Functionally, few-to-many is the same as one-to-many; but because the configuration is more complicated, we recommend creating a one-to-many configuration for each real address that requires it.

For example, for a few-to-many scenario, the few real addresses are mapped to the many mapped addresses in order (A to 1, B to 2, C to 3). When all real addresses are mapped, the next mapped address is mapped to the first real address, and so on until all mapped addresses are mapped (A to 4, B to 5, C to 6). This results in multiple mapped addresses for each real address. Just like a one-to-many configuration, only the first mappings are bidirectional; subsequent mappings allow traffic to be initiated

to

the real host, but all traffic

from

the real host uses only the first mapped address for the source.

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NAT Types


Figure 26-6

shows a typical few-to-many static NAT scenario. The first translation for each real address is always active so both translated and remote hosts can initiate connections, but the subsequent mappings are unidirectional to the real hosts.

Figure 26-6 Few-to-Many Static NAT

Security

Appliance

10.1.2.27

10.1.2.2

8

10.1.2.27

10.1.2.2

8

10.1.2.27

Inside Outside

209.165.201.

3

209.165.201.4

209.165.201.5

209.165.201.6

209.165.201.7

For a many-to-few or many-to-one configuration, where you have more real addresses than mapped addresses, you run out of mapped addresses before you run out of real addresses. Only the initial mappings result in bidirectional initiation. The remaining real addresses can initiate traffic, but traffic cannot be initiated to them (returning traffic for a connection is directed to the correct real address because of the unique 5-tuple (source IP, destination IP, source port, destination port, protocol) for the connection).

Figure 26-7

shows a typical many-to-few static NAT scenario. The first translation for each mapped address is always active so both translated and remote hosts can initiate connections, but the subsequent mappings are unidirectional from the real hosts.

Figure 26-7 Many-to-Few Static NAT

Security

Appliance

10.1.2.27

10.1.2.2

8

10.1.2.29

10.1.2.

3 0

10.1.2.

3 1

Inside Outside

209.165.201.

3

209.165.201.4

209.165.201.

3

209.165.201.4

209.165.201.

3

Instead of using a static rule this way, we suggest that you create a one-to-one rule for the traffic that needs bidirectional initiation, and then create a dynamic rule for the rest of your addresses.

Dynamic NAT

This section describes dynamic NAT and includes the following topics:

•

Information About Dynamic NAT, page 26-9

•

Dynamic NAT Disadvantages and Advantages, page 26-10

26-8


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NAT Types

Information About Dynamic NAT

Dynamic NAT translates a group of real addresses to a pool of mapped addresses that are routable on the destination network. The mapped pool typically includes fewer addresses than the real group. When a host you want to translate accesses the destination network, the adaptive security appliance assigns the host an IP address from the mapped pool. The translation is created only when the real host initiates the connection. The translation is in place only for the duration of the connection, and a given user does not keep the same IP address after the translation times out. Users on the destination network, therefore, cannot initiate a reliable connection to a host that uses dynamic NAT, even if the connection is allowed by an access rule.

Figure 26-8 shows a typical dynamic NAT scenario. Only real hosts can create a NAT session, and

responding traffic is allowed back.

Figure 26-8

Security

Appliance

10.1.1.1

Dynamic NAT

209.165.201.1

10.1.1.2

209.165.201.2

Inside Outside

Figure 26-9 shows a remote host attempting to initiate a connection to a mapped address. This address

is not currently in the translation table; therefore, the adaptive security appliance drops the packet.

Figure 26-9 Remote Host Attempts to Initiate a Connection to a Mapped Address

Web Server www.example.com

Outside

209.165.201.2

Security

Appliance

209.165.201.10

10.1.2.1

Inside

10.1.2.27

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26-9


NAT Types

Note

For the duration of the translation, a remote host can initiate a connection to the translated host if an access rule allows it. Because the address is unpredictable, a connection to the host is unlikely.

Nevertheless, in this case you can rely on the security of the access rule.

Dynamic NAT Disadvantages and Advantages

Dynamic NAT has these disadvantages:

•

If the mapped pool has fewer addresses than the real group, you could run out of addresses if the amount of traffic is more than expected.

Use PAT if this event occurs often because PAT provides over 64,000 translations using ports of a single address.

•

You have to use a large number of routable addresses in the mapped pool; if the destination network requires registered addresses, such as the Internet, you might encounter a shortage of usable addresses.

The advantage of dynamic NAT is that some protocols cannot use PAT. PAT does not work with the following:

•

•

IP protocols that do not have a port to overload, such as GRE version 0.

Some multimedia applications that have a data stream on one port, the control path on another port, and are not open standard.

See the

“When to Use Application Protocol Inspection” section on page 36-2

for more information about

NAT and PAT support.

Dynamic PAT

This section describes dynamic PAT and includes the following topics:

•

•

Information About Dynamic PAT, page 26-10

Dynamic PAT Disadvantages and Advantages, page 26-11

Information About Dynamic PAT

Dynamic PAT translates multiple real addresses to a single mapped IP address by translating the real address and source port to the mapped address and a unique port above 1024. Each connection requires a separate translation session because the source port differs for each connection. For example,

10.1.1.1:1025 requires a separate translation from 10.1.1.1:1026.

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NAT Types

Figure 26-10

shows a typical dynamic PAT scenario. Only real hosts can create a NAT session, and responding traffic is allowed back. The mapped address is the same for each translation, but the port is dynamically assigned.

Figure 26-10 Dynamic PAT

Security

Appliance

10.1.1.1:1025

10.1.1.1:1026

209.165.201.1:2020

209.165.201.1:2021

10.1.1.2:1025 209.165.201.1:2022

Inside Outside

After the connection expires, the port translation also expires after 30 seconds of inactivity. The timeout is not configurable. Users on the destination network cannot reliably initiate a connection to a host that uses PAT (even if the connection is allowed by an access rule).

Note

For the duration of the translation, a remote host can initiate a connection to the translated host if an access rule allows it. Because the port address (both real and mapped) is unpredictable, a connection to the host is unlikely. Nevertheless, in this case you can rely on the security of the access rule.

Dynamic PAT Disadvantages and Advantages

Dynamic PAT lets you use a single mapped address, thus conserving routable addresses. You can even use the adaptive security appliance interface IP address as the PAT address.

Dynamic PAT does not work with some multimedia applications that have a data stream that is different from the control path. See the

“When to Use Application Protocol Inspection” section on page 36-2

for more information about NAT and PAT support.

Identity NAT

You might have a NAT configuration in which you need to translate an IP address to itself. For example, if you create a broad rule that applies NAT to every network, but want to exclude one network from NAT, you can create a static NAT rule to translate an address to itself. Identity NAT is necessary for remote access VPN, where you need to exempt the client traffic from NAT.

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26-11


NAT in Routed and Transparent Mode

Figure 26-11 shows a typical identity NAT scenario.

Figure 26-11 Identity NAT

Security

Appliance

209.165.201.1

209.165.201.1

209.165.201.2

209.165.201.2

Inside Outside


You can configure NAT in both routed and transparent firewall mode. This section describes typical usage for each firewall mode and includes the following topics:

•

NAT in Routed Mode, page 26-13

•

NAT in Transparent Mode, page 26-13

26-12


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NAT in Routed Mode

Figure 26-12

shows a typical NAT example in routed mode, with a private network on the inside.

Figure 26-12 NAT Example: Routed Mode

Web Server www.cisco.com

Originating

Packet

Translation

10.1.2.27

209.165.201.10

Outside

209.165.201.2

Security

Appliance

Responding

Packet

Undo Translation

209.165.201.10

10.1.2.27

10.1.2.1

Inside

10.1.2.27

1.

2.

3.

When the inside host at 10.1.2.27 sends a packet to a web server, the real source address of the packet, 10.1.2.27, is changed to a mapped address, 209.165.201.10.

When the server responds, it sends the response to the mapped address, 209.165.201.10, and the adaptive security appliance receives the packet.

The adaptive security appliance then changes the translation of the mapped address,

209.165.201.10, back to the real address, 10.1.2.27, before sending it to the host.

NAT in Transparent Mode

Using NAT in transparent mode eliminates the need for the upstream or downstream routers to perform

NAT for their networks.

NAT in transparent mode has the following requirements and limitations:

•

•

When the mapped addresses are not on the same network as the transparent firewall, then on the upstream router you need to add a static route for the mapped addresses that points to the downstream router (through the adaptive security appliance).

When you have VoIP or DNS traffic with NAT and inspection enabled, to successfully translate the

IP address inside VoIP and DNS packets, the adaptive security appliance needs to perform a route lookup. Unless the host is on a directly-connected network, then you need to add a static route on the adaptive security appliance for the real host address that is embedded in the packet.

•

Because the transparent firewall does not have any interface IP addresses, you cannot use interface

PAT.

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26-13



•

ARP inspection is not supported. Moreover, if for some reason a host on one side of the adaptive security appliance sends an ARP request to a host on the other side of the adaptive security appliance, and the initiating host real address is mapped to a different address on the same subnet, then the real address remains visible in the ARP request.

Figure 26-13 shows a typical NAT scenario in transparent mode, with the same network on the inside

and outside interfaces. The transparent firewall in this scenario is performing the NAT service so that the upstream router does not have to perform NAT.

Figure 26-13 NAT Example: Transparent Mode

www.example.com

Internet


10.1.1.75 209.165.201.15

Static route on router to

209.165.201.0/27 to downstream router

Static route on security appliance for

192.168.1.1/24 to downstream router

10.1.1.2

Management IP

10.1.1.1

Security appliance

10.1.1.75

10.1.1.3

192.168.1.1

Network 2

192.168.1.2


192.16

8 .1.2 209.165.201.10

1.

2.

3.

4.

When the inside host at 10.1.1.75 sends a packet to a web server, the real source address of the packet, 10.1.1.75, is changed to a mapped address, 209.165.201.15.

When the server responds, it sends the response to the mapped address, 209.165.201.15, and the adaptive security appliance receives the packet because the upstream router includes this mapped network in a static route directed through the adaptive security appliance.

The adaptive security appliance then undoes the translation of the mapped address, 209.165.201.15, back to the real address, 10.1.1.1.75. Because the real address is directly-connected, the adaptive security appliance sends it directly to the host.

For host 192.168.1.2, the same process occurs, except that the adaptive security appliance looks up the route in its route table and sends the packet to the downstream router at 10.1.1.3 based on the static route.

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How NAT is Implemented


The adaptive security appliance can implement address translation in two ways:

network object NAT

and

twice NAT

. This section includes the following topics:

•

Main Differences Between Network Object NAT and Twice NAT, page 26-15

•

•

Information About Network Object NAT, page 26-16

Information About Twice NAT, page 26-16

Main Differences Between Network Object NAT and Twice NAT

The main differences between these two NAT types are:

•

How you define the real address.

–

–

Network object NAT—You define NAT as a parameter for a network object; the network object definition itself provides the real address. This method lets you easily add NAT to network objects. The objects can also be used in other parts of your configuration, for example, for access rules or even in twice NAT rules.

Twice NAT—You identify a network object or network object group for both the real and mapped addresses. In this case, NAT is not a parameter of the network object; the network object or group is a parameter of the NAT configuration. The ability to use a network object

group

for the real address means that twice NAT is more scalable.

•

•

How source and destination NAT is implemented.

–

Network object NAT— Each rule can apply to either the source or destination of a packet. So two rules might be used, one for the source IP address, and one for the destination IP address.

These two rules cannot be tied together to enforce a specific translation for a source/destination combination.

–

Twice NAT—A single rule translates both the source and destination. A matching packet only matches the one rule, and further rules are not checked. Even if you do not configure the optional destination address for twice NAT, a matching packet still only matches one twice NAT rule. The source and destination are tied together, so you can enforce different translations depending on the source/destination combination. For example, sourceA/destinationA can have a different translation than sourceA/destinationB.

Order of NAT Rules.

–

–

Network object NAT—Automatically ordered in the NAT table.

Twice NAT—Manually ordered in the NAT table (before or after network object NAT rules).

See the

“NAT Rule Order” section on page 26-19 for more information.

We recommend using network object NAT unless you need the extra features that twice NAT provides.

Network object NAT is easier to configure, and might be more reliable for applications such as Voice over IP (VoIP). (For VoIP, because twice NAT is applicable only between two objects, you might see a failure in the translation of indirect addresses that do not belong to either of the objects.)

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26-15



Information About Network Object NAT

All NAT rules that are configured as a parameter of a network object are considered to be network object

NAT rules. Network object NAT is a quick and easy way to configure NAT for a network object, which can be a single IP address, a range of addresses, or a subnet.

After you configure the network object, you can then identify the mapped address for that object, either as an inline address or as another network object or network object group.

When a packet enters the adaptive security appliance, both the source and destination IP addresses are checked against the network object NAT rules. The source and destination address in the packet can be translated by separate rules if separate matches are made. These rules are not tied to each other; different combinations of rules can be used depending on the traffic.

Because the rules are never paired, you cannot specify that sourceA/destinationA should have a different translation than sourceA/destinationB. Use twice NAT for that kind of functionality (twice NAT lets you identify the source and destination address in a single rule).

To start configuring network object NAT, see

Chapter 27, “Configuring Network Object NAT.”

Information About Twice NAT

Twice NAT lets you identify both the source and destination address in a single rule. Specifying both the source and destination addresses lets you specify that sourceA/destinationA can have a different translation than sourceA/destinationB.

The destination address is optional. If you specify the destination address, you can either map it to itself

(identity NAT), or you can map it to a different address. The destination mapping is always a static mapping.

Twice NAT also lets you use service objects for static NAT with port translation; network object NAT only accepts inline definition.

To start configuring twice NAT, see Chapter 28, “Configuring Twice NAT.”

Figure 26-14 shows a host on the 10.1.2.0/24 network accessing two different servers. When the host

accesses the server at 209.165.201.11, the real address is translated to 209.165.202.129. When the host accesses the server at 209.165.200.225, the real address is translated to 209.165.202.130. (See the

“Single Address for FTP, HTTP, and SMTP (Static NAT with Port Translation)” section on page 27-29

for details on how to configure this example.)

26-16


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Figure 26-14 Twice NAT with Different Destination Addresses

Server 1

209.165.201.11

Server 2

209.165.200.225

209.165.201.0/27

DMZ

209.165.200.224/27


Translation

10.1.2.27

209.165.202.129

Translation

10.1.2.27

209.165.202.1

3 0

Inside

10.1.2.0/24

Packet

Dest. Address:

209.165.201.11

10.1.2.27

Packet

Dest. Address:

209.165.200.225

Figure 26-15

shows the use of source and destination ports. The host on the 10.1.2.0/24 network accesses a single host for both web services and Telnet services. When the host accesses the server for web services, the real address is translated to 209.165.202.129. When the host accesses the same server for

Telnet services, the real address is translated to 209.165.202.130.

Figure 26-15 Twice NAT with Different Destination Ports

Web and Telnet server:

209.165.201.11

Internet

OL-20339-01

10.1.2.27: 8

Translation

0 209.165.202.129

10.1.2.27:2

Translation

3 209.165.202.1

3 0

Inside

10.1.2.0/24

Web Packet

Dest. Address:

209.165.201.11: 8 0

10.1.2.27

Telnet Packet

Dest. Address:

209.165.201.11:2 3


26-17



Figure 26-16 shows a remote host connecting to a translated host. The translated host has a twice static

NAT translation that translates the real address only for traffic to and from the 209.165.201.0/27 network. A translation does not exist for the 209.165.200.224/27 network, so the translated host cannot connect to that network, nor can a host on that network connect to the translated host.

Figure 26-16 Twice Static NAT with Destination Address Translation

209.165.201.11

209.165.200.225

209.165.201.0/27

DMZ

209.165.200.224/27

Undo Translation

209.165.202.12

10.1.2.27

Inside

10.1.2.0/27

10.1.2.27

No Translation

26-18


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NAT Rule Order

NAT Rule Order

Network object NAT rules and twice NAT rules are stored in a single table that is divided into three sections. Section 1 rules are applied first, then section 2, and finally section 3.

Table 26-2

shows the order of rules within each section.

Table 26-2 NAT Rule Table

Table Section

Section 1

Section 2

Rule Type

Twice NAT

Order of Rules within the Section

Applied on a first match basis, in the order they appear in the configuration. By default, twice NAT rules are added to section 1.

Note

If you configure VPN, the client dynamically adds invisible NAT rules to the end of this section. Be sure that you do not configure a twice NAT rule in this section that might match your VPN traffic, instead of matching the invisible rule. If VPN does not work due to NAT failure, consider adding twice NAT rules to section 3 instead.

Network object NAT Section 2 rules are applied in the following order, as automatically determined by the adaptive security appliance:

Section 3 Twice NAT

1.

2.

Static rules.

Dynamic rules.

Within each rule type, the following ordering guidelines are used:

a.

Quantity of real IP addresses—From smallest to largest. For example, an object with one address will be assessed before an object with 10 addresses.

b.

For quantities that are the same, then the IP address number is used, from lowest to highest. For example,

10.1.1.0 is assessed before 11.1.1.0.

c.

If the same IP address is used, then the name of the network object is used, in alphabetical order. For example, abracadabra is assessed before catwoman.

Section 3 rules are applied on a first match basis, in the order they appear in the configuration. You can specify whether to add a twice NAT rule to section 3 when you add the rule.

For section 2 rules for example, you have the following IP addresses defined within network objects:

192.168.1.0/24 (static)

192.168.1.0/24 (dynamic)

10.1.1.0/24 (static)

192.168.1.1/32 (static)

172.16.1.0/24 (dynamic) (object def)

172.16.1.0/24 (dynamic) (object abc)

OL-20339-01


26-19


NAT Interfaces

The resultant ordering would be:

192.168.1.1/32 (static)

10.1.1.0/24 (static)

192.168.1.0/24 (static)

172.16.1.0/24 (dynamic) (object abc)

172.16.1.0/24 (dynamic) (object def)

192.168.1.0/24 (dynamic)

NAT Interfaces

You can configure a NAT rule to apply to any interface, or you can identify specific real and mapped interfaces. You can also specify any interface for the real address, and a specific interface for the mapped address, or vice versa.

For example, you might want to specify any interface for the real address and specify the outside interface for the mapped address if you use the same private addresses on multiple interfaces, and you want to translate them all to the same global pool when accessing the outside (

Figure 26-17 ).

Figure 26-17 Specifying Any Interface

O u t s ide

10.1.2.0

209.165.201.1:xxxx

S ec u rity

Appli a nce

any

10.1.2.0

Eng

10.1.2.0

Mktg HR

10.1.2.0

Mapped Address Guidelines

When you translate the real address to a mapped address, you can use the following mapped addresses:

•

Addresses on the same network as the mapped interface.

If you use addresses on the same network as the mapped interface (through which traffic exits the adaptive security appliance), the adaptive security appliance uses proxy ARP to answer any requests for mapped addresses, and thus it intercepts traffic destined for a real address. This solution simplifies routing because the adaptive security appliance does not have to be the gateway for any additional networks. However, this approach does put a limit on the number of available addresses used for translations.

For PAT, you can even use the IP address of the mapped interface.

26-20


OL-20339-01


DNS and NAT

Note

If you configure the mapped interface to be any interface, but you specify a mapped address on the same network as one of the interfaces, then if an ARP request for that mapped address comes in on a

different

interface, then you need to manually configure an ARP entry for that network on the other interface where you specify the interface MAC address (see

Configuration > Device Management > Advanced > ARP > ARP Static Table). Typically, if you specify any interface for the mapped interface, then you use a unique network for the mapped addresses.

•

Addresses on a unique network.

If you need more addresses than are available on the mapped interface network, you can identify addresses on a different subnet. The adaptive security appliance uses proxy ARP to answer any requests for mapped addresses, and thus it intercepts traffic destined for a real address.

See additional guidelines about mapped IP addresses in

Chapter 27, “Configuring Network Object

NAT,”

and

Chapter 28, “Configuring Twice NAT.”

DNS and NAT

You might need to configure the adaptive security appliance to modify DNS replies by replacing the address in the reply with an address that matches the NAT configuration. You can configure DNS modification when you configure each translation.

This feature rewrites the A record, or address record, in DNS replies that match a NAT rule. For DNS replies traversing from a mapped interface to any other interface, the A record is rewritten from the mapped value to the real value. Inversely, for DNS replies traversing from any interface to a mapped interface, the A record is rewritten from the real value to the mapped value.

Note

If you configure a twice NAT rule, you cannot configure DNS modification if you specify the source address as well as the destination address. These kinds of rules can potentially have a different translation for a single address when going to A vs. B. Therefore, the adaptive security appliance cannot accurately match the IP address inside the DNS reply to the correct twice NAT rule; the DNS reply does not contain information about which source/destination address combination was in the packet that prompted the DNS request.

For example, a DNS server is accessible from the outside interface. A server, ftp.cisco.com, is on the inside interface. You configure the adaptive security appliance to statically translate the ftp.cisco.com real address (10.1.3.14) to a mapped address (209.165.201.10) that is visible on the outside network.

(See

Figure 26-18

.) In this case, you want to enable DNS reply modification on this static rule so that inside users who have access to ftp.cisco.com using the real address receive the real address from the

DNS server, and not the mapped address.

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26-21

DNS and NAT


When an inside host sends a DNS request for the address of ftp.cisco.com, the DNS server replies with the mapped address (209.165.201.10). The adaptive security appliance refers to the static rule for the inside server and translates the address inside the DNS reply to 10.1.3.14. If you do not enable DNS reply modification, then the inside host attempts to send traffic to 209.165.201.10 instead of accessing ftp.cisco.com directly.

Figure 26-18 DNS Reply Modification

DNS Server

1

DNS Query ftp.cisco.com?

2

DNS Reply

209.165.201.10

3

DNS Reply Modification

209.165.201.10

10.1.

3 .14

4

DNS Reply

10.1.

3 .14

Outside

Inside

Security

Appliance

5

User ftp.cisco.com

10.1.

3 .14

Static Translation on Outside to:

209.165.201.10

FTP Request

10.1.

3 .14

Note

If a user on a different network (for example, DMZ) also requests the IP address for ftp.cisco.com from the outside DNS server, then the IP address in the DNS reply is also modified for this user, even though the user is not on the Inside interface referenced by the static rule.

26-22


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Where to Go Next

Figure 26-19

shows a web server and DNS server on the outside. The adaptive security appliance has a static translation for the outside server. In this case, when an inside user requests the address for ftp.cisco.com from the DNS server, the DNS server responds with the real address, 209.165.20.10.

Because you want inside users to use the mapped address for ftp.cisco.com (10.1.2.56) you need to configure DNS reply modification for the static translation.

Figure 26-19 DNS Reply Modification Using Outside NAT

ftp.cisco.com

209.165.201.10

Static Translation on Inside to:

10.1.2.56

DNS Server

1


2

DNS Reply

209.165.201.10

3


209.165.201.10

10.1.2.56

Security

Appliance

Outside

Inside

4

DNS Reply

10.1.2.56

User

10.1.2.27

7

FTP Request

209.165.201.10

6

Dest Addr. Translation

10.1.2.56

209.165.201.10

5

FTP Request

10.1.2.56


To configure network object NAT, see

Chapter 27, “Configuring Network Object NAT.”

To configure twice NAT, see

Chapter 28, “Configuring Twice NAT.”

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26-23



26-24


OL-20339-01

C H A P T E R

27


All NAT rules that are configured as a parameter of a network object are considered to be

network object

NAT

rules. Network object NAT is a quick and easy way to configure NAT for a network object, which can be a single IP address, a range of addresses, or a subnet. After you configure the network object, you can then identify the mapped address for that object.

This chapter describes how to configure network object NAT, and it includes the following sections:

•

•

•

•

•

Information About Network Object NAT, page 27-1

Licensing Requirements for Network Object NAT, page 27-2

Prerequisites for Network Object NAT, page 27-2


•

•

Configuring Network Object NAT, page 27-3

Configuration Examples for Network Object NAT, page 27-17

Feature History for Network Object NAT, page 27-37

Note

For detailed information about how NAT works, see

Chapter 26, “Information About NAT.”

Information About Network Object NAT

When a packet enters the adaptive security appliance, both the source and destination IP addresses are checked against the network object NAT rules. The source and destination address in the packet can be translated by separate rules if separate matches are made. These rules are not tied to each other; different combinations of rules can be used depending on the traffic.

Because the rules are never paired, you cannot specify that a source address should be translated to A when going to destination X, but be translated to B when going to destination Y. Use twice NAT for that kind of functionality (twice NAT lets you identify the source and destination address in a single rule).

For detailed information about the differences between twice NAT and network object NAT, see the

“How NAT is Implemented” section on page 26-15 .

Network object NAT rules are added to section 2 of the NAT rules table. For more information about

NAT ordering, see the

“NAT Rule Order” section on page 26-19

.


27-1 OL-20339-01

Chapter 27 Configuring Network Object NAT

Licensing Requirements for Network Object NAT

Licensing Requirements for Network Object NAT


Model

All models


Base License.

Prerequisites for Network Object NAT

Depending on the configuration, you can configure the mapped address inline if desired or you can create a network object or network object group for the mapped address. Network object groups are particularly useful for creating a mapped address pool with discontinous IP address ranges or multiple hosts or subnets. To create a network object or group, see the

“Configuring Network Objects and Groups” section on page 13-1

.

For specific guidelines for objects and groups, see the configuration section for the NAT type you want to configure. See also the

“Guidelines and Limitations” section.






•


•

•

In transparent mode, you must specify the real and mapped interfaces; you cannot use --Any--.

In transparent mode, you cannot configure interface PAT, because the transparent mode interfaces do not have IP addresses. You also cannot use the management IP address as a mapped address.

IPv6 Guidelines



•

If you change the NAT configuration, and you do not want to wait for existing translations to time out before the new NAT information is used, you can clear the translation table using the

clear xlate

command. However, clearing the translation table disconnects all current connections that use translations.

Note

If you remove a dynamic NAT or PAT rule, and then add a new rule with mapped addresses that overlap the addresses in the removed rule, then the new rule will not be used until all connections associated with the removed rule time out or are cleared using the

clear xlate

command. This safeguard ensures that the same address is not assigned to multiple hosts.

27-2


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•

•

Objects and object groups used in NAT cannot be undefined; they must include IP addresses.

The mapped IP address pool cannot include:

–

The mapped interface IP address. If you specify --Any-interface for the rule, then all interface

IP addresses are disallowed. For interface PAT (routed mode only), use the interface name instead of the IP address.

–

–

–

(Transparent mode) The management IP address.

(Dynamic NAT) The standby interface IP address when VPN is enabled.

Existing VPN pool addresses.


This section describes how to configure network object NAT to create rules for dynamic NAT, dynamic

PAT, static NAT, static NAT with port translation, and identity NAT. This section includes the following topics:

•

Configuring Dynamic NAT, page 27-3

•

•

•

Configuring Dynamic PAT (Hide), page 27-7

Configuring Static NAT or Static NAT with Port Translation, page 27-11

Configuring Identity NAT, page 27-14

Configuring Dynamic NAT

This section describes how to configure a dynamic NAT rule using network object NAT. For more information, see the

“Dynamic NAT” section on page 26-8 .

Detailed Steps

Step 1

You can add NAT to a new or existing network object:

•

To add a new network object, choose

Configuration

>

Firewall

>

NAT Rules

, then click

Add >

Add Network Object NAT Rule

.

Figure 27-1 Adding a Network Object NAT Rule

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27-3



Step 2

•

To add NAT to an existing network object, choose

Configuration > Firewall > Objects > Network

Objects/Groups

, and then double-click a named network object. (Non-named network objects cannot be configured for NAT. Named network object icons have dark blue accents, and non-named network object icons have green accents and the word “IP”.)




For a new object, enter values for the following fields:

a.

Name—The object name. Use characters a to z, A to Z, 0 to 9, a period, a dash, a comma, or an underscore. The name must be 64 characters or less.

b.

c.

Type—Host, Network, or Range.

IP Address—An IPv4 address. IPv6 is not supported. If you select Range as the object type, the IP

Address field changes to allow you to enter a Start Address and an End address.

d.

e.

Netmask—Enter the subnet mask.


Figure 27-2 Defining the Object Addresses

Step 3

Step 4

Step 5

If the NAT section is hidden, click

NAT

to expand the section.

Check the

Add Automatic Translation Rules

check box.

From the Type drop-down list, choose

Dynamic

.

27-4


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Figure 27-3 Enabling NAT


OL-20339-01

Step 6

In the Translated Addr field, click the browse button and choose an existing network object from the

Browse Translated Addr dialog box.

Note

The object or group cannot contain a subnet.

You can share this mapped object across different dynamic NAT rules, if desired.

Figure 27-4 Browse Dialog Box

See the

“Guidelines and Limitations” section on page 27-2

for information about disallowed mapped IP addresses.

You can also create a new named object from the Browse Translated Addr dialog box and use this object as the mapped address:

a.

Add the new network object.

Figure 27-5 Adding a New Network Object for the NAT Pool


27-5

Configuring Network Object NAT b.

Define the NAT pool addresses, and click

OK

.

Figure 27-6 Defining the NAT Pool Addresses


Note

Although not disallowed, you will typically not configure NAT for this network object that you are using for the mapped addresses; you can leave the NAT section unconfigured.

c.

Choose the new network object by double-clicking it. Click

OK

to return to the NAT configuration.

Figure 27-7 Choosing the New Network Object

Step 7

Step 8

(Optional) To use the interface IP address as a backup method when the other mapped addresses are already allocated, check the

Fall through to interface PAT (dest intf)

check box, and choose the interface from the drop-down list.

(Optional) Click

Advanced

, and configure the following options in the Advanced NAT Settings dialog box. When you are finished, click

OK

.

27-6


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Figure 27-8 Configuring Advanced NAT Settings


Step 9

•

•

To translate the IP address in DNS replies, check the

Translate DNS replies for rule

check box.

Be sure DNS inspection is enabled (it is enabled by default). See the

“DNS and NAT” section on page 26-21


To specify the real and/or mapped interfaces where this NAT rule should apply, under Interface, choose the source and destination interfaces.

By default, the rule applies to all interfaces.

You return to the Add/Edit Network Object dialog box.

Click

OK

, and then

Apply

.

Configuring Dynamic PAT (Hide)

This section describes how to configure a dynamic PAT (hide) rule using network object NAT. For more information, see the

“Dynamic PAT” section on page 26-10

.

Detailed Steps

Step 1


•



.

Configuration

>

Firewall

>

NAT Rules

, then click

Add >

OL-20339-01


27-7




Step 2

•



Objects/Groups






a.

b.

c.


Type—Host, Network, or Range.

d.

e.






Step 3

Step 4

Step 5


NAT


Check the


check box.


Dynamic PAT (Hide)

.

27-8


OL-20339-01


Figure 27-11 Configuring Dynamic PAT


OL-20339-01

Step 6

In the Translated Addr field, specify the mapped IP address.

Note

You can share this mapped IP address across different dynamic PAT rules, if desired.


•

•

Type a host IP address.

Type an interface name or click the browse button , and choose an interface from the Browse

Translated Addr dialog box.


If you specify an interface name, then you enable

interface PAT

, where the specified interface IP address is used as the mapped address. With interface PAT, the NAT rule only applies to the specified mapped interface. (If you do not use interface PAT, then the rule applies to all interfaces by default.)

See Step 8 to optionally also configure the real interface to be a specific interface instead of --Any--.

Note

You cannot specify an interface in transparent mode.

•

Click the browse button , and choose an existing host address from the Browse Translated Addr dialog box. You can also create a new named object from the Browse Translated Addr dialog box and use this object as the mapped address.


27-9




Step 7

See the

“Guidelines and Limitations” section on page 27-2 for information about disallowed mapped IP

addresses.

(Optional) Click

Advanced


OK

.


Step 8

•

•



check box.







Click

OK

, and then

Apply

.

27-10


OL-20339-01



Configuring Static NAT or Static NAT with Port Translation

This section describes how to configure a static NAT rule using network object NAT. For more information, see the

“Static NAT” section on page 26-3

.

Detailed Steps

Step 1


•



.

Configuration

>

Firewall

>

NAT Rules

, then click

Add >


OL-20339-01

Step 2

•



Objects/Groups



“Configuring a Network Object” section on page 13-2

.



a.


d.

e.

b.

c.

Type—Network, Host, or Range.






27-11




Step 3

Step 4

Step 5


NAT


Check the


check box.


Static

.

Figure 27-17 Configuring NAT

Step 6

In the Translated Addr field, do one of the following:

•

Type an IP address.

•

When you type an IP address, the netmask or range for the mapped network is the same as that of the real network. For example, if the real network is a host, then this address will be a host address.

In the case of a range, then the mapped addresses include the same number of addresses as the real range. For example, if the real address is defined as a range from 10.1.1.1 through 10.1.1.6, and you specify 172.20.1.1 as the mapped address, then the mapped range will include 172.20.1.1 through

172.20.1.6.

(For static NAT with port translation only) Type an interface name or click the browse button , and choose an interface from the Browse Translated Addr dialog box.


27-12


OL-20339-01



•

Be sure to also configure a service on the Advanced NAT Settings dialog box (see

Step 7 ). (You

cannot specify an interface in transparent mode).

Click the browse button , and choose an existing address from the Browse Translated Addr dialog box. You can also create a new named object from the Browse Translated Addr dialog box and use this object as the mapped address.


Step 7

See the



Typically, you configure the same number of mapped addresses as real addresses for a one-to-one mapping. You can, however, have a mismatched number of addresses. For more information, see the

“Static NAT” section on page 26-3 .

(Optional) Click

Advanced


OK

.


OL-20339-01

•

•

•



check box.



for more information. This option is not available if you also translate TCP or UDP ports

(static NAT with port translation).



To configure static NAT with port translation, under Service, choose the protocol type from the

Protocol drop-down list (

tcp

or

udp)

, and then type values for the Original Port and Translated Port.


27-13



Step 8

You can type either a port number or a well-known port name (such as “ftp”).


Click

OK

, and then

Apply

.

Because static rules are bidirectional (allowing initiation to and from the real host), the NAT Rules table show two rows for each static rule, one for each direction (see

Figure 27-21

).

Figure 27-21 Bidirectional Rules in the NAT Rules Table

Configuring Identity NAT

This section describes how to configure an identity NAT rule using network object NAT. For more information, see the

“Identity NAT” section on page 26-11 .

Detailed Steps

Step 1


•


Configuration

>

Firewall

>

NAT Rules

, then click

Add >


.


•



Objects/Groups


27-14


OL-20339-01



Step 2


“Configuring a Network Object” section on page 13-2

.



a.

b.

c.


Type—Network, Host, or Range.

d.

e.






Step 3

Step 4

Step 5


NAT


Check the


check box.


Static

.


OL-20339-01

Step 6

In the Translated Addr field, do one of the following:

•

Type the same IP address that you used for the real address.


27-15



•

Click the browse button , and choose a network object with a matching IP address definition from the Browse Translated Addr dialog box. You can also create a new named object from the Browse

Translated Addr dialog box and use this object as the mapped address.


Step 7

(Optional) To specify the real and/or mapped interfaces where this NAT rule should apply, click

Advanced

, and under Interface, choose the source and destination interfaces. By default, the rule applies to all interfaces.

Do not configure any other options on this dialog box.

Click

OK

to return to the Add/Edit Network Object dialog box.

Figure 27-26 Configuring Interfaces

Step 8

Click

OK

, and then

Apply

.

Because static rules are bidirectional (allowing initiation to and from the real host), the NAT Rules table show two rows for each static rule, one for each direction (see

Figure 27-21

).

27-16


OL-20339-01


Figure 27-27 Bidirectional Rules in the NAT Rules Table

Configuration Examples for Network Object NAT


This section includes the following configuration examples:

•

Providing Access to an Inside Web Server (Static NAT), page 27-18

•

•

NAT for Inside Hosts (Dynamic NAT) and NAT for an Outside Web Server (Static NAT), page 27-20

Inside Load Balancer with Multiple Mapped Addresses (Static NAT, One-to-Many), page 27-25

•

•

•

Single Address for FTP, HTTP, and SMTP (Static NAT with Port Translation), page 27-29

DNS Server on Mapped Interface, Web Server on Real Interface (Static NAT with DNS

Modification), page 27-32

DNS Server and Web Server on Mapped Interface, Web Server is Translated (Static NAT with DNS

Modification), page 27-35

OL-20339-01


27-17



Providing Access to an Inside Web Server (Static NAT)

The following example performs static NAT for an inside web server. The real address is on a private network, so a public address is required. Static NAT is necessary so hosts can initiate traffic to the web server at a fixed address. (See

Figure 27-28

).

Figure 27-28 Static NAT for an Inside Web Server

209.165.201.12

Undo Tr a n s l a tion

10.1.2.27

209.165.201.10

O u t s ide

209.165.201.1

S ec u rity

Appli a nce

10.1.2.1

In s ide myWe bS erv

10.1.2.27

Step 1

Create a network object for the internal web server:

Figure 27-29 Adding a Network Object

Step 2

Define the web server address:

27-18


OL-20339-01


Figure 27-30 Defining the Web Server Address


Step 3

Configure static NAT for the object:


Step 4

Configure the real and mapped interfaces by clicking

Advanced

:

OL-20339-01


27-19




Step 5

Click

OK

to return to the Edit Network Object dialog box, click

OK

again, and then click

Apply

.

NAT for Inside Hosts (Dynamic NAT) and NAT for an Outside Web Server

(Static NAT)

The following example configures dynamic NAT for inside users on a private network when they access the outside. Also, when inside users connect to an outside web server, that web server address is

translated to an address that appears to be on the inside network. (See Figure 27-33 ).

27-20


OL-20339-01


Figure 27-33


Dynamic NAT for Inside, Static NAT for Outside Web Server

We b S erver

209.165.201.12

10.1.2.10

Tr a n s l a tion

209.165.201.20

Undo Tr a n s l a tion

209.165.201.12

10.1.2.20

O u t s ide

209.165.201.1

S ec u rity

Appli a nce

10.1.2.1

In s ide myIn s Net

10.1.2.0/24

Step 1

Create a network object for the inside network:


OL-20339-01

Step 2

Define the addresses for the inside network:


27-21


Figure 27-35 Defining the Inside Network Addresses


Step 3

Enable dynamic NAT for the inside network:

Figure 27-36 Enabling NAT

Step 4

For the Translated Addr field, add a new network object for the dynamic NAT pool to which you want to translate the inside addresses by clicking the browse button .

a.


Figure 27-37 Adding a New Network Object for the NAT Pool

b.

Define the NAT pool addresses, and click

OK

.

27-22


OL-20339-01


Figure 27-38 Defining the NAT Pool Addresses

Configuration Examples for Network Object NAT c.


OK



Step 5


Advanced

:


OL-20339-01

Step 6

Step 7

Click

OK

to return to the Edit Network Object dialog box, click then click

OK

again to return to the

NAT Rules table.

Create a network object for the outside web server:


27-23




Step 8

Define the web server address:

Figure 27-42 Defining the Web Server Address

Step 9

Configure static NAT for the web server:


Step 10


Advanced

:

27-24


OL-20339-01




Step 11

Click

OK


OK


Apply

.

Inside Load Balancer with Multiple Mapped Addresses (Static NAT,

One-to-Many)

The following example shows an inside load balancer that is translated to multiple IP addresses. When an outside host accesses one of the mapped IP addresses, it is untranslated to the single load balancer address. Depending on the URL requested, it redirects traffic to the correct web server. (See

Figure 27-45

).

OL-20339-01


27-25



Figure 27-45 Static NAT with One-to-Many for an Inside Load Balancer

Host

Undo Translation

209.165.201.

3 10.1.2.27

Outside

Undo Translation

209.165.201.5

10.1.2.27

Undo Translation

209.165.201.4

10.1.2.27

Inside

Load Balancer

10.1.2.27

Web Servers

Step 1

Create a network object for the load balancer:


Step 2

Define the load balancer address:

27-26


OL-20339-01


Figure 27-47 Defining the Load Balancer Address


Step 3

Configure static NAT for the load balancer:


Step 4

For the Translated Addr field, add a new network object for the static NAT group of addresses to which you want to translate the load balancer address by clicking the browse button .

a.


Figure 27-49 Adding a New Network Object for the Static NAT Group

OL-20339-01 b.

Define the static NAT group of addresses, and click

OK

.


27-27


Figure 27-50 Defining the Static NAT Group of Addresses

Chapter 27 Configuring Network Object NAT c.


OK



Step 5


Advanced

:


Step 6

Click

OK


OK


Apply

.

27-28


OL-20339-01



Single Address for FTP, HTTP, and SMTP (Static NAT with Port Translation)

The following static NAT with port translation example provides a single address for remote users to access FTP, HTTP, and SMTP. These servers are actually different devices on the real network, but for each server, you can specify static NAT with port translation rules that use the same mapped IP address, but different ports. (See

Figure 27-53 .)

Figure 27-53 Static NAT with Port Translation

Host

Undo Translation

209.165.201.

3 :21 10.1.2.27

Outside

Undo Translation

209.165.201.

3 :25 10.1.2.29

Undo Translation

209.165.201.

3 : 8 0 10.1.2.2

8

Inside

FTP server

10.1.2.27

SMTP server

HTTP server

10.1.2.2

8

10.1.2.29

Step 1

Create a network object for the FTP server address:


OL-20339-01

Step 2

Define the FTP server address, and configure static NAT for the FTP server:


27-29



Figure 27-55 Defining the FTP Server Address and Configuring Static NAT

Step 3

Click

Advanced

to configure the real and mapped interfaces and port translation for FTP.

Figure 27-56 Setting the Interfaces and Port

Step 4

Create a network object for the HTTP server address:


27-30

Step 5

Define the HTTP server address, and configure static NAT for the HTTP server:


OL-20339-01


Figure 27-58


Defining the HTTP Server Address and Configuring Static NAT

Step 6

Click

Advanced

to configure the real and mapped interfaces and port translation for HTTP.


Step 7

Create a network object for the SMTP server address:


OL-20339-01

Step 8

Define the SMTP server address, and configure static NAT for the SMTP server:


27-31



Figure 27-61 Defining the SMTP Server Address and Configuring Static NAT

Step 9

Click

Advanced

to configure the real and mapped interfaces and port translation for SMTP.


Step 10

Click

OK


OK


Apply

.

DNS Server on Mapped Interface, Web Server on Real Interface (Static NAT with DNS Modification)

For example, a DNS server is accessible from the outside interface. A server, ftp.cisco.com, is on the inside interface. You configure the adaptive security appliance to statically translate the ftp.cisco.com real address (10.1.3.14) to a mapped address (209.165.201.10) that is visible on the outside network.

(See

Figure 27-63 .) In this case, you want to enable DNS reply modification on this static rule so that

inside users who have access to ftp.cisco.com using the real address receive the real address from the

DNS server, and not the mapped address.

27-32


OL-20339-01



When an inside host sends a DNS request for the address of ftp.cisco.com, the DNS server replies with the mapped address (209.165.201.10). The adaptive security appliance refers to the static rule for the inside server and translates the address inside the DNS reply to 10.1.3.14. If you do not enable DNS reply modification, then the inside host attempts to send traffic to 209.165.201.10 instead of accessing ftp.cisco.com directly.

Figure 27-63 DNS Reply Modification

DNS Server

1


2

DNS Reply

209.165.201.10

3


209.165.201.10

10.1.

3 .14

4

DNS Reply

10.1.

3 .14

Outside

Inside

Security

Appliance

5

User ftp.cisco.com

10.1.

3 .14

Static Translation on Outside to:

209.165.201.10

FTP Request

10.1.

3 .14

Step 1


OL-20339-01


27-33




Step 2

Define the FTP server address, and configure static NAT:


Step 3

Click

Advanced

to configure the real and mapped interfaces and DNS modification.

Figure 27-66 Setting the Interfaces and DNS

27-34


OL-20339-01



Step 4

Click

OK


OK


Apply

.

DNS Server and Web Server on Mapped Interface, Web Server is Translated

(Static NAT with DNS Modification)

Figure 27-67

shows a web server and DNS server on the outside. The adaptive security appliance has a static translation for the outside server. In this case, when an inside user requests the address for ftp.cisco.com from the DNS server, the DNS server responds with the real address, 209.165.20.10.

Because you want inside users to use the mapped address for ftp.cisco.com (10.1.2.56) you need to configure DNS reply modification for the static translation.

Figure 27-67 DNS Reply Modification Using Outside NAT

ftp.cisco.com

209.165.201.10

Static Translation on Inside to:

10.1.2.56

DNS Server

1


2

DNS Reply

209.165.201.10

3


209.165.201.10

10.1.2.56

Security

Appliance

Outside

Inside

4

DNS Reply

10.1.2.56

User

10.1.2.27

7

FTP Request

209.165.201.10

6

Dest Addr. Translation

10.1.2.56

209.165.201.10

5

FTP Request

10.1.2.56

Step 1


OL-20339-01


27-35




Step 2

Define the FTP server address, and configure static NAT:


Step 3

Click

Advanced

to configure the real and mapped interfaces and DNS modification.

Figure 27-70 Setting the Interfaces and DNS

27-36


OL-20339-01


Feature History for Network Object NAT

Step 4

Click

OK


OK


Apply

.


Table 27-1


Table 27-1

Feature Name

Feature History for Network Object NAT

Network Object NAT

Platform

Releases

8.3(1)


Configures NAT for a network object IP address(es).

The following screens were introduced or modified:

Configuration > Firewall > NAT Rules

Configuration > Firewall > Objects > Network

Objects/Groups

OL-20339-01


27-37



27-38


OL-20339-01


C H A P T E R

28

Twice NAT lets you identify both the source and destination address in a single rule. This chapter shows you how to configure twice NAT and includes the following sections:

•

Information About Twice NAT, page 28-1

•

•

•

•

•

•

Licensing Requirements for Twice NAT, page 28-1

Prerequisites for Twice NAT, page 28-2


Configuring Twice NAT, page 28-3

Configuration Examples for Twice NAT, page 28-18

Feature History for Twice NAT, page 28-37

Note

For detailed information about how NAT works, see

Chapter 26, “Information About NAT.”

Information About Twice NAT

Twice NAT lets you identify both the source and destination address in a single rule. Specifying both the source and destination addresses lets you specify that a source address should be translated to A when going to destination X, but be translated to B when going to destination Y, for example.

The destination address is optional. If you specify the destination address, you can either map it to itself

(identity NAT), or you can map it to a different address. The destination mapping is always a static mapping.

Twice NAT also lets you use service objects for static NAT with port translation; network object NAT only accepts inline definition.

For detailed information about the differences between twice NAT and network object NAT, see the

“How NAT is Implemented” section on page 26-15 .

Twice NAT rules are added to section 1 of the NAT rules table, or if specified, section 3. For more information about NAT ordering, see the

“NAT Rule Order” section on page 26-19

.

Licensing Requirements for Twice NAT


28-1 OL-20339-01

Chapter 28 Configuring Twice NAT

Prerequisites for Twice NAT

Model

All models


Base License.

Prerequisites for Twice NAT

•

For both the real and mapped addresses, configure network objects or network object groups.

Network object groups are particularly useful for creating a mapped address pool with discontinuous

IP address ranges or multiple hosts or subnets. To create a network object or group, see the

“Configuring Network Objects and Groups” section on page 13-1

.

•

For static NAT with port translation, configure TCP or UDP service objects. To create a service object, see the

“Configuring Service Objects and Service Groups” section on page 13-5 .

For specific guidelines for objects and groups, see the configuration section for the NAT type you want to configure. See also the

“Guidelines and Limitations” section.






•


•

In transparent mode, you must specify the real and mapped interfaces; you cannot use --Any--.

•

In transparent mode, you cannot configure interface PAT, because the transparent mode interfaces do not have IP addresses. You also cannot use the management IP address as a mapped address.

IPv6 Guidelines



•

If you change the NAT configuration, and you do not want to wait for existing translations to time out before the new NAT information is used, you can clear the translation table using the

clear xlate

command. However, clearing the translation table disconnects all current connections that use translations.

Note

If you remove a dynamic NAT or PAT rule, and then add a new rule with mapped addresses that overlap the addresses in the removed rule, then the new rule will not be used until all connections associated with the removed rule time out or are cleared using the

clear xlate

command. This safeguard ensures that the same address is not assigned to multiple hosts.

•

Objects and object groups used in NAT cannot be undefined; they must include IP addresses.

28-2


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•

The mapped IP address pool cannot include:

–

–

The mapped interface IP address. If you specify --Any--

IP addresses are disallowed. For interface PAT (routed mode only), use the interface name instead of the IP address.

(Transparent mode) The management IP address.

interface for the rule, then all interface

–

–

(Dynamic NAT) The standby interface IP address when VPN is enabled.

Existing VPN pool addresses.


This section describes how to configure twice NAT to create rules for dynamic NAT, dynamic PAT, static

NAT, static NAT with port translation, and identity NAT. This section includes the following topics:

•

•

•

•

Configuring Dynamic NAT, page 28-3

Configuring Dynamic PAT (Hide), page 28-7

Configuring Static NAT or Static NAT with Port Translation, page 28-11

Configuring Identity NAT, page 28-15

s

Configuring Dynamic NAT

This section describes how to configure a dynamic NAT rule using twice NAT. For more information about dynamic NAT, see the

“Dynamic NAT” section on page 26-8 .

Detailed Steps

To configure dynamic NAT, perform the following steps:

Step 1

Choose

Configuration > Firewall > NAT Rules

, and then click

Add

.

If you want to add this rule to section 3 after the network object rules, then click the down arrow next to

Add, and choose

Add NAT Rule After Network Object NAT Rules

.

Figure 28-1 Adding a NAT Rule

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The Add NAT Rule dialog box appears.


28-3


Figure 28-2 Add NAT Rule Dialog Box


Step 2

Set the source and destination interfaces.

By default, both interfaces are set to --Any--.

a.

From the Match Criteria: Original Packet > Source Interface drop-down list, choose the source interface.

b.

From the Match Criteria: Original Packet > Destination Interface drop-down list, choose the destination interface.

Figure 28-3 Setting the Interfaces

Step 3

Identify the original packet addresses (the real source address and the mapped destination address).

a.

For the Match Criteria: Original Packet > Source Address, click the browse button and choose an existing network object or group from the Browse Original Source Address dialog box. The default is

any

.


b.

You can also create a new named object or group from the Browse Original Source Address dialog box and use this object or group as the real source address.

(Optional) For the Match Criteria: Original Packet > Destination Address, click the browse button

and choose an existing network object or group from the Browse Original Destination Address dialog box.

28-4


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Step 4

Step 5

You can also create a new named object or group from the Browse Original Destination Address dialog box and use this object or group as the real destination address.

Although the main feature of twice NAT is the inclusion of the destination IP address, the destination address is optional. If you do specify the destination address, you can configure static translation for that address or just use identity NAT for it. You might want to configure twice NAT without a destination address to take advantage of some of the other qualities of twice NAT, including the use of network object groups for real addresses, or manually ordering of rules. For more information,

see the “Main Differences Between Network Object NAT and Twice NAT” section on page 26-15 .

(Optional) Identify the original packet port (the mapped destination port). For the Match Criteria:

Original Packet > Service, click the browse button and choose an existing TCP or UDP service object from the Browse Original Service dialog box.

You can also create a new service object from the Browse Original Service dialog box and use this object as the real destination port.

Dynamic NAT does not support port translation. However, because the destination translation is always static, you can perform port translation for the destination port. A service object can contain both a source and destination port, but only the destination port is used in this case. If you specify the source port, it will be ignored. NAT only supports TCP or UDP. When translating a port, be sure the protocols in the real and mapped service objects are identical (both TCP or both UDP). For identity NAT, you can use the same service object for both the real and mapped ports. The “not equal” (

!=

) operator is not supported.

Choose

Dynamic

from the Match Criteria: Translated Packet > Source NAT Type drop-down list.

This setting only applies to the source address; the destination translation is always static.

Figure 28-5 Setting the NAT Type

Step 6

Identify the translated packet addresses (the mapped source address and the real destination address).

a.

For the Match Criteria: Translated Packet > Source Address, click the browse button and choose an existing network object or group from the Browse Translated Source Address dialog box.

You can also create a new named object or group from the Browse Translated Source Address dialog box and use this object or group as the mapped source address.

For dynamic NAT, you typically configure a larger group of source addresses to be mapped to a smaller group.

Note

You can share this mapped object across different dynamic NAT rules, if desired.

b.

For the Match Criteria: Translated Packet > Destination Address, click the browse button and choose an existing network object, group, or interface from the Browse Translated Destination

Address dialog box.

You can also create a new named object or group from the Browse Translated Destination Address dialog box and use this object or group as the mapped destination address.

For identity NAT for the destination address, simply use the same object or group for both the real and mapped addresses.

OL-20339-01


28-5



If you want to translate the destination address, then the static mapping is typically one-to-one, so the real addresses have the same quantity as the mapped addresses. You can, however, have different quantities if desired. For more information, see the


. See the


addresses.

For static interface NAT with port translation only, choose an interface. If you specify an interface, be sure to also configure a a service translation. For this option, you must configure a specific interface for the Source Interface.

See the “Static Interface NAT with Port Translation” section on page 26-5 for more information.


Step 7

Step 8

(Optional) Identify the translated packet port (the real destination port). For the Match Criteria:

Translated Packet > Service, click the browse button and choose an existing TCP or UDP service object from the Browse Translated Service dialog box.

You can also create a new service object from the Browse Translated Service dialog box and use this object as the mapped destination port.

Dynamic NAT does not support port translation. However, because the destination translation is always static, you can perform port translation for the destination port. A service object can contain both a source and destination port, but only the destination port is used in this case. If you specify the source port, it will be ignored. NAT only supports TCP or UDP. When translating a port, be sure the protocols in the real and mapped service objects are identical (both TCP or both UDP). For identity NAT, you can use the same service object for both the real and mapped ports. The “not equal” (

!=


(Optional) To use the interface IP address as a backup method if the other mapped addresses are already allocated, check the

Fall through to interface PAT

check box.

The destination interface IP address is used. This option is only available if you configure a specific

Destination Interface.

Figure 28-7 Fall Through to Interface PAT

Step 9

(Optional) Configure NAT options in the Options area.

28-6


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Figure 28-8 NAT Options


Step 10 a.

b.

Check the

Enable rule

check box to enable this NAT rule. The rule is enabled by default.

(For a source-only rule) To rewrite the DNS A record in DNS replies, check the

Translate DNS replies that match this rule

check box.

Be sure DNS inspection is enabled (it is enabled by default). You cannot configure DNS modification if you configure a destination address. See the



c.

In the Description field, add a description about the rule up to 200 characters in length.

Click

OK

.

Configuring Dynamic PAT (Hide)

This section describes how to configure a dynamic PAT (hide) rule using twice NAT. For more information about dynamic PAT, see the

“Dynamic PAT” section on page 26-10 .

Detailed Steps

To configure dynamic PAT, perform the following steps:

Step 1

Choose


, and then click

Add

.


Add, and choose


.


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28-7




Step 2



a.


b.



Step 3


a.


any

.


b.




28-8


OL-20339-01



Step 4

Step 5




(Optional) Identify the original packet port (the mapped destination port). For the Match Criteria:

Original Packet > Service, click the browse button and choose an existing TCP or UDP service object from the Browse Original Service dialog box.


Dynamic PAT does not support additional port translation. However, because the destination translation is always static, you can perform port translation for the destination port. A service object can contain both a source and destination port, but only the destination port is used in this case. If you specify the source port, it will be ignored. NAT only supports TCP or UDP. When translating a port, be sure the protocols in the real and mapped service objects are identical (both TCP or both UDP). For identity NAT, you can use the same service object for both the real and mapped ports. The “not equal” (

!=


Choose


from the Match Criteria: Translated Packet > Source NAT Type drop-down list.



OL-20339-01

Step 6


a.

For the Match Criteria: Translated Packet > Source Address, click the browse button and choose an existing network object or interface from the Browse Translated Source Address dialog box.


You can also create a new named object (host) from the Browse Translated Source Address dialog box and use this object as the mapped source address.

For dynamic PAT, you configure a group of addresses to be mapped to a single address.


28-9



Step 7

Step 8

Note

You can share this mapped object across different dynamic PAT rules, if desired.

b.

For the Match Criteria: Translated Packet > Destination Address, click the browse button and choose an existing network object or group from the Browse Translated Destination Address dialog box.





. See the


addresses.

For static interface NAT with port translation only, choose an interface. If you specify an interface, be sure to also configure a a service translation. For this option, you must configure a specific interface for the Source Interface. See the

“Static Interface NAT with Port Translation” section on page 26-5 for more information.

(Optional) Identify the translated packet port (the real destination port). For the Match Criteria:

Translated Packet > Service, click the browse button and choose an existing TCP or UDP service object from the Browse Translated Service dialog box.


Dynamic PAT does not support additional port translation. However, because the destination translation is always static, you can perform port translation for the destination port. A service object can contain both a source and destination port, but only the destination port is used in this case. If you specify the source port, it will be ignored. NAT only supports TCP or UDP. When translating a port, be sure the protocols in the real and mapped service objects are identical (both TCP or both UDP). For identity NAT, you can use the same service object for both the real and mapped ports. The “not equal” (

!=




a.

b.

Check the

Enable rule


(For a source-only rule) To rewrite the DNS A record in DNS replies, check the


check box.

28-10


OL-20339-01



Step 9

Be sure DNS inspection is enabled (it is enabled by default). You cannot configure DNS modification if you configure a destination address. See the



c.


Click

OK

.

Configuring Static NAT or Static NAT with Port Translation

This section describes how to configure a static NAT rule using twice NAT. For more information about

static NAT, see the “Static NAT” section on page 26-3

.

Detailed Steps

To configure static NAT, perform the following steps:

Step 1

Choose


, and then click

Add

.


Add, and choose


.



OL-20339-01


28-11




Step 2


By default, both interfaces are set to Any.

a.


b.



Step 3


a.


any

, but you typically only use this option when also setting the mapped address to

any

for identity NAT. See the

“Configuring Identity NAT” section on page 28-15



b.




28-12


OL-20339-01



Step 4

Step 5




(Optional) Identify the original packet source or destination port (the real source port or the mapped destination port). For the Match Criteria: Original Packet > Service, click the browse button and choose an existing TCP or UDP service object from the Browse Original Service dialog box.

You can also create a new service object from the Browse Original Service dialog box and use this object as the real port.

A service object can contain both a source and destination port. You should specify either the source or the destination port for both the real and mapped service objects. You should only specify both the source and destination ports if your application uses a fixed source port (such as some DNS servers); but fixed source ports are rare. In the rare case where you specify both the source and destination ports in the object, the original packet service object contains the real source port/mapped destination port; the translated packet service object contains the mapped source port/real destination port. NAT only supports TCP or UDP. When translating a port, be sure the protocols in the real and mapped service objects are identical (both TCP or both UDP). For identity NAT, you can use the same service object for both the real and mapped ports. The “not equal” (

!=


Choose

Static

from the Match Criteria: Translated Packet > Source NAT Type drop-down list. Static is the default setting.



Step 6


a.

For the Match Criteria: Translated Packet > Source Address, click the browse button and choose an existing network object or group from the Browse Translated Source Address dialog box.


OL-20339-01

You can also create a new named object or group from the Browse Translated Source Address dialog box and use this object or group as the mapped source address.

For static NAT, the mapping is typically one-to-one, so the real addresses have the same quantity as the mapped addresses. You can, however, have different quantities if desired.

For static interface NAT with port translation, you can specify the interface instead of a network object/group for the mapped address. For more information, see the

“Static Interface NAT with Port

Translation” section on page 26-5 .

See the




28-13



Step 7

Step 8 b.


Address dialog box.


For static NAT, the mapping is typically one-to-one, so the real addresses have the same quantity as the mapped addresses. You can, however, have different quantities if desired.

For static interface NAT with port translation, you can specify the interface instead of a network

object/group for the mapped address. For more information, see the “Static Interface NAT with Port

Translation” section on page 26-5 .

See the

“Guidelines and Limitations” section on page 28-2 for information about disallowed

mapped IP addresses.

(Optional) Identify the translated packet source or destination port (the mapped source port or the real destination port). For the Match Criteria: Translated Packet > Service, click the browse button and choose an existing TCP or UDP service object from the Browse Translated Service dialog box.

You can also create a new service object from the Browse Translated Service dialog box and use this object as the mapped port.

A service object can contain both a source and destination port. You should specify either the source or the destination port for both real and mapped service objects. You should only specify both the source and destination ports if your application uses a fixed source port (such as some DNS servers); but fixed source ports are rare. In the rare case where you specify both the source and destination ports in the object, the original packet service object contains the real source port/mapped destination port; the translated packet service object contains the mapped source port/real destination port. NAT only supports TCP or UDP. When translating a port, be sure the protocols in the real and mapped service objects are identical (both TCP or both UDP). For identity NAT, you can use the same service object for both the real and mapped ports. The “not equal” (

!=




a.

b.

c.

d.

Check the

Enable rule


To rewrite the DNS A record in DNS replies, check the


check box.




To make the rule unidirectional, choose

Unidirectional

from the Direction drop-down list. The default is Both. Making the rule unidirectional prevents traffic from initiating connections to the real addresses. You might want to use this setting for testing purposes.


28-14


OL-20339-01



Step 9

Click

OK

.

Configuring Identity NAT

This section describes how to configure an identity NAT rule using twice NAT. You configure identity

NAT using a static NAT rule where you map an address to itself. For more information about identity

NAT, see the

“Identity NAT” section on page 26-11 .

Detailed Steps

To configure identity NAT, perform the following steps:

Step 1

Choose


, and then click

Add

.


Add, and choose


.



OL-20339-01


28-15




Step 2



a.


b.



Step 3


a.


any

, only use this option when also setting the mapped address to

any

.


b.




28-16


OL-20339-01



Step 4

Step 5




(Optional) Identify the original packet source or destination port (the real source port or the mapped destination port). For the Match Criteria: Original Packet > Service, click the browse button and choose an existing TCP or UDP service object from the Browse Original Service dialog box.


A service object can contain both a source and destination port. You should specify either the source or the destination port for both service objects. You should only specify both the source and destination ports if your application uses a fixed source port (such as some DNS servers); but fixed source ports are rare. In the rare case where you specify both the source and destination ports in the object, the original packet service object contains the real source port/mapped destination port; the translated packet service object contains the mapped source port/real destination port. NAT only supports TCP or UDP. When translating a port, be sure the protocols in the real and mapped service objects are identical (both TCP or both UDP). For identity NAT, you can use the same service object for both the real and mapped ports.

The “not equal” (

!=


Choose

Static

from the Match Criteria: Translated Packet > Source NAT Type drop-down list. Static is the default setting.



Step 6


a.

b.

For the Match Criteria: Translated Packet > Source Address, click the browse button and choose the same network object or group from the Browse Translated Source Address dialog box that you chose for the real source address. Use

any

if you specified

any

for the real address.


Address dialog box.




“Static NAT” section on page 26-3 . See the


addresses.

OL-20339-01


28-17


Configuration Examples for Twice NAT

Step 7

Step 8

For static interface NAT with port translation only, choose an interface. If you specify an interface, be sure to also configure a a service translation. For more information, see the

“Static Interface NAT with Port Translation” section on page 26-5

.

(Optional) Identify the translated packet source or destination port (the mapped source port or the real destination port). For the Match Criteria: Translated Packet > Service, click the browse button and choose an existing TCP or UDP service object from the Browse Translated Service dialog box.


A service object can contain both a source and destination port. You should specify either the source or the destination port for both service objects. You should only specify both the source and destination ports if your application uses a fixed source port (such as some DNS servers); but fixed source ports are rare. In the rare case where you specify both the source and destination ports in the object, the original packet service object contains the real source port/mapped destination port; the translated packet service object contains the mapped source port/real destination port. NAT only supports TCP or UDP. When translating a port, be sure the protocols in the real and mapped service objects are identical (both TCP or both UDP). For identity NAT, you can use the same service object for both the real and mapped ports.

The “not equal” (

!=




a.

b.

c.

Check the

Enable rule


To make the rule unidirectional, choose

Unidirectional

from the Direction drop-down list. The default is Both. Making the rule unidirectional prevents traffic from initiating connections to the real addresses. You might want to use this setting for testing purposes.


Note

Although the “Translate DNS replies that match this rule” check box is available (if you do not configure a destination address), this option is not applicable to identity NAT because you are

translating the address to itself, so the DNS reply does not need modification. See the “DNS and

NAT” section on page 26-21


Step 9

Click

OK

.


This section includes the following configuration examples:

28-18


OL-20339-01



•

•

Different Translation Depending on the Destination (Dynamic PAT), page 28-19

Different Translation Depending on the Destination Address and Port (Dynamic PAT), page 28-28

Different Translation Depending on the Destination (Dynamic PAT)

Figure 28-29

shows a host on the 10.1.2.0/24 network accessing two different servers. When the host accesses the server at 209.165.201.11, the real address is translated to 209.165.202.129:

port

. When the host accesses the server at 209.165.200.225, the real address is translated to 209.165.202.130:

port

.

Figure 28-29 Twice NAT with Different Destination Addresses

Server 1

209.165.201.11

Server 2

209.165.200.225

209.165.201.0/27

DMZ

209.165.200.224/27

Translation

10.1.2.27

209.165.202.129

Translation

10.1.2.27

209.165.202.1

3 0

Inside

10.1.2.0/24

Packet

Dest. Address:

209.165.201.11

10.1.2.27

Packet

Dest. Address:

209.165.200.225

Step 1

Add a NAT rule for traffic from the inside network to DMZ network 1:


OL-20339-01


28-19



By default, the NAT rule is added to the end of section 1. If you want to add a NAT rule to section 3, after the network object NAT rules, choose


.



Step 2

Set the source and destination interfaces:


Step 3

For the Original Source Address, click the browse button to add a new network object for the inside network in the Browse Original Source Address dialog box.

a.


Figure 28-33 Adding a New Network Object for the Inside Network

b.

Define the inside network addresses, and click

OK

.

28-20


OL-20339-01



Configuration Examples for Twice NAT c.


OK



Step 4

For the Original Destination Address, click the browse button to add a new network object for DMZ network 1 in the Browse Original Destination Address dialog box.

a.


Figure 28-36 Adding a New Network Object for the DMZ Network 1

b.

Define the DMZ network 1 addresses, and click

OK

.

OL-20339-01


28-21


Figure 28-37 Defining the DMZ Network 1 Addresses

Chapter 28 Configuring Twice NAT c.


OK



Step 5

Set the NAT Type to


:


Step 6

For the Translated Source Address, click the browse button to add a new network object for the PAT address in the Browse Translated Source Address dialog box.

a.


Figure 28-40 Adding a New Network Object for the PAT Address

28-22 b.

Define the PAT address, and click

OK

.


OL-20339-01


Figure 28-41 Defining the PAT Address



OK



Step 7

For the Translated Destination Address, type the name of the Original Destination Address

(DMZnetwork1) or click the browse button to choose it.

Because you do not want to translate the destination address, you need to configure identity NAT for it by specifying the same address for the Original and Translated destination addresses.

Figure 28-43 Add NAT Rule Dialog Box: Completed

OL-20339-01

Step 8

Step 9

Click

OK

to add the rule to the NAT table.

Add a NAT rule for traffic from the inside network to DMZ network 2:


28-23






.



Step 10



Step 11

Step 12

For the Original Source Address, type the name of the inside network object (myInsideNetwork) or click the browse button to choose it.

For the Original Destination Address, click the browse button to add a new network object for DMZ network 2 in the Browse Original Destination Address dialog box.

a.


28-24


OL-20339-01


Figure 28-47


Adding a New Network Object for the DMZ Network 2

b.

Define the DMZ network 2 addresses, and click

OK

.

Figure 28-48 Defining the DMZ Network 2 Addresses

c.


OK



Step 13

Set the NAT Type to


:


OL-20339-01

Step 14


a.



28-25



Chapter 28 Configuring Twice NAT b.


OK

.


c.


OK



Step 15


(DMZnetwork2) or click the browse button to choose it.


28-26


OL-20339-01




Step 16

Step 17

Click

OK


Click

Apply

.

OL-20339-01


28-27



Different Translation Depending on the Destination Address and Port (Dynamic

PAT)

Figure 28-55 shows the use of source and destination ports. The host on the 10.1.2.0/24 network accesses

a single host for both web services and Telnet services. When the host accesses the server for web services, the real address is translated to 209.165.202.129:

port

. When the host accesses the same server for Telnet services, the real address is translated to 209.165.202.130:

port

.

Figure 28-55 Twice NAT with Different Destination Ports

Web and Telnet server:

209.165.201.11

Internet

10.1.2.27: 8

Translation

0 209.165.202.129

10.1.2.27:2

Translation

3 209.165.202.1

3 0

Inside

10.1.2.0/24

Web Packet

Dest. Address:

209.165.201.11: 8 0

10.1.2.27

Telnet Packet

Dest. Address:

209.165.201.11:2 3

Step 1

Add a NAT rule for traffic from the inside network to the Telnet server:




.

28-28


OL-20339-01





Step 2



Step 3

For the Original Source Address, click the browse button to add a new network object for the inside network in the Browse Original Source Address dialog box.

a.


Figure 28-59 Adding a New Network Object for the Inside Network

OL-20339-01 b.

Define the inside network addresses, and click

OK

.


28-29





OK



Step 4

For the Original Destination Address, click the browse button to add a new network object for the

Telnet/Web server in the Browse Original Destination Address dialog box.

a.


Figure 28-62 Adding a New Network Object for the Telnet/Web Server

b.

Define the server address, and click

OK

.

28-30


OL-20339-01


Figure 28-63 Defining the Server Address



OK



Step 5

For the Original Service, click the browse button to add a new service object for Telnet in the Browse

Original Service dialog box.

a.

Add the new service object.

Figure 28-65 Adding a New Service Object for Telnet

b.

Define the protocol and port, and click

OK

.

OL-20339-01


28-31


Figure 28-66 Defining the Protocol and Port


Choose the new service object by double-clicking it. Click

OK


Figure 28-67 Choosing the New Service Object

Step 6

Set the NAT Type to


:


Step 7


a.



28-32


OL-20339-01

Chapter 28 Configuring Twice NAT b.


OK

.




OK



Step 8


(TelnetWebServer) or click the browse button to choose it.



OL-20339-01

Step 9

Step 10

Click

OK


Add a NAT rule for traffic from the inside network to the web server:


28-33






.



Step 11

Set the real and mapped interfaces:


Step 12

Step 13

For the Original Source Address, type the name of the inside network object (myInsideNetwork) or click the browse button to choose it.

For the Original Destination Address, type the name of the Telnet/web server network object


28-34


OL-20339-01



Step 14

For the Original Service, click the browse button to add a new service object for HTTP in the Browse

Original Service dialog box.

a.

Add the new service object.

Figure 28-76 Adding a New Service Object for HTTP

b.

Define the protocol and port, and click

OK

.

Figure 28-77 Defining the Protocol and Port

OL-20339-01 c.

Choose the new service object by double-clicking it. Click

OK


Figure 28-78 Choosing the New Service Object

Step 15

Set the NAT Type to


:


28-35




Step 16


a.



b.


OK

.


c.


OK



28-36


OL-20339-01


Feature History for Twice NAT

Step 17





Step 18

Step 19

Click

OK


Click

Apply

.


Table 28-1


Table 28-1 Feature History for Twice NAT

Feature Name

Twice NAT

Platform

Releases

8.3(1)


Twice NAT lets you identify both the source and destination address in a single rule.


Firewall > NAT Rules.

OL-20339-01


28-37



28-38


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P

A R T

6

Configuring Service Policies

C H A P T E R

29

Configuring a Service Policy

Service policies provide a consistent and flexible way to configure adaptive security appliance features.

For example, you can use a service policy to create a timeout configuration that is specific to a particular

TCP application, as opposed to one that applies to all TCP applications. A service policy consists of multiple service policy rules applied to an interface or applied globally.


•

•

•

•

•

Information About Service Policies, page 29-1

Licensing Requirements for Service Policies, page 29-6



•

•

•

•

Task Flows for Configuring Service Policies, page 29-8

Adding a Service Policy Rule for Through Traffic, page 29-8

Adding a Service Policy Rule for Management Traffic, page 29-12

Managing the Order of Service Policy Rules, page 29-15

Feature History for Service Policies, page 29-16

Information About Service Policies

This section describes how service policies work and includes the following topics:

•

Supported Features for Through Traffic, page 29-1

•

•

•

•

•

•

Supported Features for Management Traffic, page 29-2

Feature Directionality, page 29-2

Feature Matching Within a Service Policy, page 29-3

Order in Which Multiple Feature Actions are Applied, page 29-4

Incompatibility of Certain Feature Actions, page 29-5

Feature Matching for Multiple Service Policies, page 29-5

Supported Features for Through Traffic

Table 29-1

lists the features supported by service policy rules.

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29-1

Chapter 29 Configuring a Service Policy


Table 29-1 Service Policy Rule Features

Feature

Application inspection (multiple types)

See:

•

Chapter 36, “Getting Started With Application Layer

Protocol Inspection.”

•

Chapter 37, “Configuring Inspection of Basic Internet

Protocols.”

•

•

Chapter 39, “Configuring Inspection of Database and

Directory Protocols.”

Chapter 40, “Configuring Inspection for Management

Application Protocols.”

CSC

IPS

•

Chapter 38, “Configuring Inspection for Voice and

Video Protocols.”

Chapter 55, “Configuring the Content Security and Control

Application on the CSC SSM.”

Chapter 54, “Configuring the IPS Application on the

AIP SSM and SSC.”


Chapter 72, “Configuring NetFlow Secure Event Logging

(NSEL).”

QoS input and output policing

Chapter 49, “Configuring QoS.”

QoS standard priority queue

QoS traffic shaping, hierarchical priority queue

TCP and UDP connection limits and timeouts, and TCP sequence number randomization



Chapter 48, “Configuring Connection Settings.”

TCP normalization

TCP state bypass



Supported Features for Management Traffic

Service policy rules support the following features for management traffic:

•

Application inspection for RADIUS accounting traffic—See

Chapter 40, “Configuring Inspection for Management Application Protocols.”

•

Connection limits—See Chapter 48, “Configuring Connection Settings.”

Feature Directionality

Actions are applied to traffic bidirectionally or unidirectionally depending on the feature. For features that are applied bidirectionally, all traffic that enters or exits the interface to which you apply the policy map is affected if the traffic matches the class map for both directions.

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Note

When you use a global policy, all features are unidirectional; features that are normally bidirectional when applied to a single interface only apply to the ingress of each interface when applied globally.

Because the policy is applied to all interfaces, the policy will be applied in both directions so bidirectionality in this case is redundant.

For features that are applied unidirectionally, for example QoS priority queue, only traffic that enters (or exits, depending on the feature) the interface to which you apply the policy map is affected. See

Table 29-2

for the directionality of each feature.

Table 29-2 Feature Directionality

Feature


CSC

IPS


QoS input policing

QoS output policing


Single Interface Direction Global Direction

Bidirectional Ingress

Bidirectional

Bidirectional

Ingress

Ingress

N/A

Ingress

Egress

Egress

Ingress

Ingress

Egress

Egress

Egress QoS traffic shaping, hierarchical priority queue

TCP and UDP connection limits and timeouts, and TCP sequence number randomization

Egress

Bidirectional

TCP normalization

TCP state bypass

Bidirectional

Bidirectional

Ingress

Ingress

Ingress

Feature Matching Within a Service Policy

See the following information for how a packet matches rules in a policy for a given interface:

1.

A packet can match only one rule for an interface for each feature type.

2.

3.

When the packet matches a rule for a feature type, the adaptive security appliance does not attempt to match it to any subsequent rules for that feature type.

If the packet matches a subsequent rule for a different feature type, however, then the adaptive security appliance also applies the actions for the subsequent rule, if supported. See the

“Incompatibility of Certain Feature Actions” section on page 29-5 for more information about

unsupported combinations.

For example, if a packet matches a rulefor connection limits, and also matches a rule for application inspection, then both actions are applied.

If a packet matches a rulefor HTTP inspection, but also matches another rule that includes HTTP inspection, then the second rule actions are not applied.

Note

Application inspection includes multiple inspection types, and each inspection type is a separate feature when you consider the matching guidelines above.

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29-3



Order in Which Multiple Feature Actions are Applied

The order in which different types of actions in a service policy are performed is independent of the order in which the actions appear in the table.

Note

NetFlow Secure Event Logging filtering is order-independent.

Actions are performed in the following order:

1.

QoS input policing

2.

TCP normalization, TCP and UDP connection limits and timeouts, TCP sequence number randomization, and TCP state bypass.

Note

When a the adaptive security appliance performs a proxy service (such as AAA or CSC) or it modifies the TCP payload (such as FTP inspection), the TCP normalizer acts in dual mode, where it is applied before and after the proxy or payload modifying service.

3.

4.

CSC


The order of application inspections applied when a class of traffic is classified for multiple inspections is as follows. Only one inspection type can be applied to the same traffic. WAAS inspection is an exception, because it can be applied along with other inspections for the same

traffic. See the “Incompatibility of Certain Feature Actions” section on page 29-5


a.

CTIQBE

b.

DNS

c.

FTP

d.

GTP

e.

H323

f.

HTTP

g.

ICMP

h.

ICMP error

i.

ILS

j.

MGCP

k.

NetBIOS

l.

PPTP

m.

Sun RPC

n.

RSH

o.

RTSP

p.

SIP

q.

Skinny

r.

SMTP

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Information About Service Policies s.

SNMP

t.

SQL*Net

u.

TFTP

v.

w.

XDMCP

DCERPC

x.

Instant Messaging

Note

RADIUS accounting is not listed because it is the only inspection allowed on management traffic. WAAS is not listed because it can be configured along with other inspections for the same traffic.

5.

6.

7.

8.

IPS

QoS output policing


QoS traffic shaping, hierarchical priority queue

Incompatibility of Certain Feature Actions

Some features are not compatible with each other for the same traffic. For example, you cannot configure

QoS priority queueing and QoS policing for the same set of traffic. Also, most inspections should not be combined with another inspection, so the adaptive security appliance only applies one inspection if you configure multiple inspections for the same traffic. In this case, the feature that is applied is the higher priority feature in the list in the

“Order in Which Multiple Feature Actions are Applied” section on page 29-4

.

For information about compatibility of each feature, see the chapter or section for your feature.

Note

The Default Inspection Traffic traffic class, which is used in the default global policy, is a special CLI shortcut to match the default ports for all inspections. When used in a policy map, this class map ensures that the correct inspection is applied to each packet, based on the destination port of the traffic. For example, when UDP traffic for port 69 reaches the adaptive security appliance, then the adaptive security appliance applies the TFTP inspection; when TCP traffic for port 21 arrives, then the adaptive security appliance applies the FTP inspection. So in this case only, you can configure multiple inspections for the same class map. Normally, the adaptive security appliance does not use the port number to determine which inspection to apply, thus giving you the flexibility to apply inspections to non-standard ports, for example.

Feature Matching for Multiple Service Policies

For TCP and UDP traffic (and ICMP when you enable stateful ICMP inspection), service policies operate on traffic flows, and not just individual packets. If traffic is part of an existing connection that matches a feature in a policy on one interface, that traffic flow cannot also match the same feature in a policy on another interface; only the first policy is used.

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29-5


Licensing Requirements for Service Policies

For example, if HTTP traffic matches a policy on the inside interface to inspect HTTP traffic, and you have a separate policy on the outside interface for HTTP inspection, then that traffic is not also inspected on the egress of the outside interface. Similarly, the return traffic for that connection will not be inspected by the ingress policy of the outside interface, nor by the egress policy of the inside interface.

For traffic that is not treated as a flow, for example ICMP when you do not enable stateful ICMP inspection, returning traffic can match a different policy map on the returning interface. For example, if you configure IPS on the inside and outside interfaces, but the inside policy uses virtual sensor 1 while the outside policy uses virtual sensor 2, then a non-stateful Ping will match virtual sensor 1 outbound, but will match virtual sensor 2 inbound.

Licensing Requirements for Service Policies

Model

All models


Base License.







IPv6 Guidelines

Supports IPv6 for the following features:

•

•

Application inspection for FTP, HTTP, ICMP, SIP, SMTP and IPSec-pass-thru

IPS

•

•

•

•


TCP and UDP connection limits and timeouts, TCP sequence number randomization

TCP normalization

TCP state bypass

Traffic Class Guidelines

The maximum number of traffic classes of all types is 255 in single mode or per context in multiple mode. Class maps include the following types:

•

Layer 3/4 class maps (for through traffic and management traffic)

•

•

•

Inspection class maps

Regular expression class maps

match

commands used directly underneath an inspection policy map


29-6 OL-20339-01



This limit also includes default traffic classes of all types. See the

“Default Traffic Classes” section on page 29-8

.

Service Policy Guidelines

•

Interface service policies take precedence over the global service policy for a given feature. For example, if you have a global policy with FTP inspection, and an interface policy with TCP normalization, then both FTP inspection and TCP normalization are applied to the interface.

However, if you have a global policy with FTP inspection, and an interface policy with FTP inspection, then only the interface policy FTP inspection is applied to that interface.

•

You can only apply one global policy. For example, you cannot create a global policy that includes feature set 1, and a separate global policy that includes feature set 2. All features must be included in a single policy.


The following topics describe the default settings for Modular Policy Framework:

•

Default Configuration, page 29-7

•

Default Traffic Classes, page 29-8

Default Configuration

•

•

•

•

•

•

By default, the configuration includes a policy that matches all default application inspection traffic and applies certain inspections to the traffic on all interfaces (a global policy). Not all inspections are enabled by default. You can only apply one global policy, so if you want to alter the global policy, you need to either edit the default policy or disable it and apply a new one. (An interface policy overrides the global policy for a particular feature.)

The default policy includes the following application inspections:

•

DNS inspection for the maximum message length of 512 bytes

•

•

FTP

H323 (H225)

H323 (RAS)

RSH

•

•

•

RTSP

ESMTP

SQLnet

Skinny (SCCP)

•

•

SunRPC

XDMCP

SIP

NetBios

TFTP

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Task Flows for Configuring Service Policies

Default Traffic Classes

The configuration includes a default traffic class that the adaptive security appliance uses in the default global policy called Default Inspection Traffic; it matches the default inspection traffic. This class, which is used in the default global policy, is a special shortcut to match the default ports for all inspections. When used in a policy, this class ensures that the correct inspection is applied to each packet, based on the destination port of the traffic. For example, when UDP traffic for port 69 reaches the adaptive security appliance, then the adaptive security appliance applies the TFTP inspection; when TCP traffic for port 21 arrives, then the adaptive security appliance applies the FTP inspection. So in this case only, you can configure multiple inspections for the same class map. Normally, the adaptive security appliance does not use the port number to determine which inspection to apply, thus giving you the flexibility to apply inspections to non-standard ports, for example.

Another class map that exists in the default configuration is called class-default, and it matches all traffic. You can use the class-default class if desired, rather than using the Any traffic class. In fact, some features are only available for class-default, such as QoS traffic shaping.

Task Flows for Configuring Service Policies


•

Task Flow for Configuring a Service Policy Rule, page 29-8

Task Flow for Configuring a Service Policy Rule

Configuring a service policy consists of adding one or more service policy rules per interface or for the global policy. For each rule, you identify the following elements:

Step 1

Step 2

Step 3

Identify the interface to which you want to apply the rule, or identify the global policy.

Identify the traffic to which you want to apply actions. You can identify Layer 3 and 4 through traffic.

Apply actions to the traffic class. You can apply multiple actions for each traffic class.

Adding a Service Policy Rule for Through Traffic

See the

“Supported Features for Through Traffic” section on page 29-1

for more information. To add a service policy rule for through traffic, perform the following steps:

Step 1

Choose

Configuration

>

Firewall

>

Service Policy Rules

pane, and click

Add

.

The Add Service Policy Rule Wizard - Service Policy dialog box appears.

Note

When you click the Add button, and not the small arrow on the right of the Add button, you add a through traffic rule by default. If you click the arrow on the Add button, you can choose between a through traffic rule and a management traffic rule.

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Step 2

Step 3

Step 4

In the Create a Service Policy and Apply To area, click one of the following options:

• Interface

. This option applies the service policy to a single interface. Interface service policies take precedence over the global service policy for a given feature. For example, if you have a global policy with FTP inspection, and an interface policy with TCP connection limits, then both FTP inspection and TCP connection limits are applied to the interface. However, if you have a global policy with FTP inspection, and an interface policy with FTP inspection, then only the interface policy FTP inspection is applied to that interface.

a.


•

If you choose an interface that already has a policy, then the wizard lets you add a new service policy rule to the interface.

b.

If it is a new service policy, enter a name in the Policy Name field.

c.

(Optional) Enter a description in the Description field.

Global - applies to all interfaces

. This option applies the service policy globally to all interfaces.

By default, a global policy exists that includes a service policy rule for default application

inspection. See the “Default Settings” section on page 29-7

for more information. You can add a rule to the global policy using the wizard.

Click

Next

.

The Add Service Policy Rule Wizard - Traffic Classification Criteria dialog box appears.

Click one of the following options to specify the traffic to which to apply the policy actions:

•

Create a new traffic class

. Enter a traffic class name in the Create a new traffic class field, and enter an optional description.

Identify the traffic using one of several criteria:

–

Default Inspection Traffic

—The class matches the default TCP and UDP ports used by all applications that the adaptive security appliance can inspect.

–

This option, which is used in the default global policy, is a special shortcut that when used in a rule, ensures that the correct inspection is applied to each packet, based on the destination port of the traffic. For example, when UDP traffic for port 69 reaches the adaptive security appliance, then the adaptive security appliance applies the TFTP inspection; when TCP traffic for port 21 arrives, then the adaptive security appliance applies the FTP inspection. So in this case only, you can configure multiple inspections for the same rule (See the

“Incompatibility of Certain

Feature Actions” section on page 29-5

for more information about combining actions).

Normally, the adaptive security appliance does not use the port number to determine the inspection applied, thus giving you the flexibility to apply inspections to non-standard ports, for example.

See the

“Default Settings” section on page 36-3

for a list of default ports. The adaptive security appliance includes a default global policy that matches the default inspection traffic, and applies common inspections to the traffic on all interfaces. Not all applications whose ports are included in the Default Inspection Traffic class are enabled by default in the policy map.

You can specify a Source and Destination IP Address (uses ACL) class along with the Default

Inspection Traffic class to narrow the matched traffic. Because the Default Inspection Traffic class specifies the ports and protocols to match, any ports and protocols in the access list are ignored.

Source and Destination IP Address (uses ACL)

—The class matches traffic specified by an extended access list. If the adaptive security appliance is operating in transparent firewall mode, you can use an EtherType access list.

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29-9



Note

When you create a new traffic class of this type, you can only specify one access control entry (ACE) initially. After you finish adding the rule, you can add additional ACEs by adding a new rule to the same interface or global policy, and then specifying

Add rule to existing traffic class

on the Traffic Classification dialog box (see below).

–

Tunnel Group

—The class matches traffic for a tunnel group to which you want to apply QoS.

You can also specify one other traffic match option to refine the traffic match, excluding Any

Traffic, Source and Destination IP Address (uses ACL), or Default Inspection Traffic.

–

TCP or UDP Destination Port

—The class matches a single port or a contiguous range of ports.

Step 5

Step 6

Tip

For applications that use multiple, non-contiguous ports, use the Source and Destination IP

Address (uses ACL) to match each port.

–

RTP Range

—The class map matches RTP traffic.

–

–

IP DiffServ CodePoints (DSCP)

—The class matches up to eight DSCP values in the IP header.

IP Precedence

—The class map matches up to four precedence values, represented by the TOS byte in the IP header.

–

Any Traffic

—Matches all traffic.

•

•


. If you already have a service policy rule on the same interface, or you are adding to the global service policy, this option lets you add an ACE to an existing access list. You can add an ACE to any access list that you previously created when you chose the Source and Destination IP Address (uses ACL) option for a service policy rule on this interface. For this traffic class, you can have only one set of rule actions even if you add multiple ACEs. You can add multiple ACEs to the same traffic class by repeating this entire procedure. See the

“Managing the

Order of Service Policy Rules” section on page 29-15 for information about changing the order of

ACEs.

Use an existing traffic class.

If you created a traffic class used by a rule on a different interface, you can reuse the traffic class definition for this rule. Note that if you alter the traffic class for one rule, the change is inherited by all rules that use that traffic class. If your configuration includes any

class-map

commands that you entered at the CLI, those traffic class names are also available

(although to view the definition of the traffic class, you need to create the rule).

• Use class default as the traffic class

. This option uses the class-default class, which matches all traffic. The class-default class is created automatically by the adaptive security appliance and placed at the end of the policy. If you do not apply any actions to it, it is still created by the adaptive security appliance, but for internal purposes only. You can apply actions to this class, if desired, which might be more convenient than creating a new traffic class that matches all traffic. You can only create one rule for this service policy using the class-default class, because each traffic class can only be associated with a single rule per service policy.

Click

Next

.

The next dialog box depends on the traffic match criteria you chose.

Note

The Any Traffic option does not have a special dialog box for additional configuration.

•

Default Inspections—This dialog box is informational only, and shows the applications and the ports that are included in the traffic class.

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•

•

Source and Destination Address—This dialog box lets you set the source and destination addresses:

a.

Click

Match

or

Do Not Match

.

The Match option creates a rule where traffic matching the addresses have actions applied. The

Do Not Match option exempts the traffic from having the specified actions applied. For example, you want to match all traffic in 10.1.1.0/24 and apply connection limits to it, except for 10.1.1.25. In this case, create two rules, one for 10.1.1.0/24 using the Match option and one for 10.1.1.25 using the Do Not Match option. Be sure to arrange the rules so that the Do Not

Match rule is above the Match rule, or else 10.1.1.25 will match the Match rule first.

b.

In the Source field, enter the source IP address, or click the

...

button to choose an IP address that you already defined in ASDM.

Specify the address and subnet mask using prefix/length notation, such as 10.1.1.0/24. If you enter an IP address without a mask, it is considered to be a host address, even if it ends with a 0.

Enter

any

to specify any source address.

Separate multiple addresses by a comma.

c.

In the Destination field, enter the destination IP address, or click the

...



Enter

any

to specify any destination address.


d.

In the Service field, enter an IP service name or number for the destination service, or click the

...

button to choose a service.

If you want to specify a TCP or UDP port number, or an ICMP service number, enter

protocol

/

port

. For example, enter TCP/8080.

By default, the service is IP.

Separate multiple services by a comma.

e.


f.

(Optional) To specify a source service for TCP or UDP, click the

More Options

area open, and enter a TCP or UDP service in the Source Service field.

g.

The destination service and source service must be the same. Copy and paste the destination

Service field to the Source Service field.

(Optional) To make the rule inactive, click the

More Options

area open, and uncheck

Enable

Rule

.

h.

This setting might be useful if you do not want to remove the rule, but want to turn it off.

(Optional) To set a time range for the rule, click the

More Options

area open, and from the Time

Range drop-down list, choose a time range.

To add a new time range, click the

...

button. See the

“Configuring Time Ranges” section on page 13-15


This setting might be useful if you only want the rule to be active at predefined times.

Tunnel Group—Choose a tunnel group from the Tunnel Group drop-down list, or click

New

to add a new tunnel group. See the

“IPsec Remote Access Connection Profiles” section on page 64-70


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29-11


Adding a Service Policy Rule for Management Traffic

Step 7

Step 8

Step 9

•

•

•

To police each flow, check

Match flow destination IP address

. All traffic going to a unique IP destination address is considered a flow.

Destination Port—Click

TCP

or

UDP

.

In the Service field, enter a port number or name, or click

...

to choose one already defined in ASDM.

RTP Range—Enter an RTP port range, between 2000 and 65534. The maximum number of port sin the range is 16383.

IP DiffServ CodePoints (DSCP)—In the DSCP Value to Add area, choose a value from the

Select

Named DSCP Values

or enter a value in the

Enter DSCP Value (0-63) field

, and click

Add

.

•

Add additional values as desired, or remove them using the

Remove

button.

IP Precedence—From the Available IP Precedence area, choose a value and click

Add

.

Add additional values as desired, or remove them using the

Remove

button.

Click

Next

.

The Add Service Policy Rule - Rule Actions dialog box appears.

Configure one or more rule actions. See the

“Supported Features for Through Traffic” section on page 29-1 for a list of features.

Click

Finish

.


You can create a service policy for traffic directed to the adaptive security appliance for management purposes. See the

“Supported Features for Management Traffic” section on page 29-2

for more information. This section includes the following topics:

Configuring a Service Policy Rule for Management Traffic

To add a service policy rule for management traffic, perform the following steps:

Step 1

Step 2

Step 3

From the Configuration > Firewall > Service Policy Rules pane, click the down arrow next to Add.

Choose

Add Management Service Policy Rule

.

The Add Management Service Policy Rule Wizard - Service Policy dialog box appears.

In the Create a Service Policy and Apply To area, click one of the following options:

•

Interface

. This option applies the service policy to a single interface. Interface service policies take precedence over the global service policy for a given feature. For example, if you have a global policy with RADIUS accounting inspection, and an interface policy with connection limits, then both RADIUS accounting and connection limits are applied to the interface. However, if you have a global policy with RADIUS accounting, and an interface policy with RADIUS accounting, then only the interface policy RADIUS accounting is applied to that interface.

a.


If you choose an interface that already has a policy, then the wizard lets you add a new service policy rule to the interface.

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Step 4

Step 5

• b.

If it is a new service policy, enter a name in the Policy Name field.

c.



. This option applies the service policy globally to all interfaces.

By default, a global policy exists that includes a service policy rule for default application

inspection. See the “Default Settings” section on page 29-7

for more information. You can add a rule to the global policy using the wizard.

Click

Next

.

The Add Management Service Policy Rule Wizard - Traffic Classification Criteria dialog box appears.

Click one of the following options to specify the traffic to which to apply the policy actions:

•


. Enter a traffic class name in the Create a new traffic class field, and enter an optional description.

Identify the traffic using one of several criteria:

–


—The class matches traffic specified by an extended access list. If the adaptive security appliance is operating in transparent firewall mode, you can use an EtherType access list.

Note

When you create a new traffic class of this type, you can only specify one access control entry (ACE) initially. After you finish adding the rule, you can add additional ACEs by adding a new rule to the same interface or global policy, and then specifying


on the Traffic Classification dialog box (see below).

–

TCP or UDP Destination Port

—The class matches a single port or a contiguous range of ports.

Step 6

Step 7

Tip

For applications that use multiple, non-contiguous ports, use the Source and Destination IP

Address (uses ACL) to match each port.

•

•


. If you already have a service policy rule on the same interface, or you are adding to the global service policy, this option lets you add an ACE to an existing access list. You can add an ACE to any access list that you previously created when you chose the Source and Destination IP Address (uses ACL) option for a service policy rule on this interface. For this traffic class, you can have only one set of rule actions even if you add multiple ACEs. You can add multiple ACEs to the same traffic class by repeating this entire procedure. See the

“Managing the

Order of Service Policy Rules” section on page 29-15 for information about changing the order of

ACEs.

Use an existing traffic class.

If you created a traffic class used by a rule on a different interface, you can reuse the traffic class definition for this rule. Note that if you alter the traffic class for one rule, the change is inherited by all rules that use that traffic class. If your configuration includes any

class-map

commands that you entered at the CLI, those traffic class names are also available

(although to view the definition of the traffic class, you need to create the rule).

Click

Next

.

The next dialog box depends on the traffic match criteria you chose.

•

Source and Destination Address—This dialog box lets you set the source and destination addresses:

a.

Click

Match

or

Do Not Match

.

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29-13



Step 8

Step 9

The Match option creates a rule where traffic matching the addresses have actions applied. The

Do Not Match option exempts the traffic from having the specified actions applied. For example, you want to match all traffic in 10.1.1.0/24 and apply connection limits to it, except for 10.1.1.25. In this case, create two rules, one for 10.1.1.0/24 using the Match option and one for 10.1.1.25 using the Do Not Match option. Be sure to arrange the rules so that the Do Not

Match rule is above the Match rule, or else 10.1.1.25 will match the Match rule first.

b.

In the Source field, enter the source IP address, or click the

...



Enter

any

to specify any source address.


c.

In the Destination field, enter the destination IP address, or click the

...



Enter

any

to specify any destination address.


d.

In the Service field, enter an IP service name or number for the destination service, or click the

...

button to choose a service.

If you want to specify a TCP or UDP port number, or an ICMP service number, enter

protocol

/

port

. For example, enter TCP/8080.

By default, the service is IP.

Separate multiple services by a comma.

e.


f.

(Optional) To specify a source service for TCP or UDP, click the

More Options

area open, and enter a TCP or UDP service in the Source Service field.

The destination service and source service must be the same. Copy and paste the destination

Service field to the Source Service field.

g.

(Optional) To make the rule inactive, click the

More Options

area open, and uncheck

Enable

Rule

.

This setting might be useful if you do not want to remove the rule, but want to turn it off.

h.

(Optional) To set a time range for the rule, click the

More Options

area open, and from the Time

Range drop-down list, choose a time range.

To add a new time range, click the

...

button. See the “Configuring Time Ranges” section on page 13-15


This setting might be useful if you only want the rule to be active at predefined times.

•

Destination Port—Click

TCP

or

UDP

.

In the Service field, enter a port number or name, or click

...

to choose one already defined in ASDM.

Click

Next

.

The Add Management Service Policy Rule - Rule Actions dialog box appears.

To configure RADIUS accounting inspection, choose an inspect map from the RADIUS Accounting

Map drop-down list, or click

Configure

to add a map.


29-14 OL-20339-01


Managing the Order of Service Policy Rules

Step 10

Step 11

See the

“Supported Features for Management Traffic” section on page 29-2


To configure connection settings, see the “Configuring Connection Settings” section on page 48-8

.

Click

Finish

.

Managing the Order of Service Policy Rules

The order of service policy rules on an interface or in the global policy affects how actions are applied to traffic. See the following guidelines for how a packet matches rules in a service policy:

•

•

A packet can match only one rule in a service policy for each feature type.

When the packet matches a rule that includes actions for a feature type, the adaptive security appliance does not attempt to match it to any subsequent rules including that feature type.

•

If the packet matches a subsequent rule for a different feature type, however, then the adaptive security appliance also applies the actions for the subsequent rule.

For example, if a packet matches a rule for connection limits, and also matches a rule for application inspection, then both rule actions are applied.

If a packet matches a rule for application inspection, but also matches another rule that includes application inspection, then the second rule actions are not applied.

If your rule includes an access list with multiple ACEs, then the order of ACEs also affects the packet flow. The FWSM tests the packet against each ACE in the order in which the entries are listed. After a match is found, no more ACEs are checked. For example, if you create an ACE at the beginning of an access list that explicitly permits all traffic, no further statements are ever checked.

To change the order of rules or ACEs within a rule, perform the following steps:

Step 1

Step 2

From the Configuration > Firewall > Service Policy Rules pane, choose the rule or ACE that you want to move up or down.

Click the Move Up or Move Down cursor (see

Figure 29-1 ).

Figure 29-1 Moving an ACE

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29-15


Feature History for Service Policies

Step 3

Note

If you rearrange ACEs in an access list that is used in multiple service policies, then the change is inherited in all service policies.

When you are done rearranging your rules or ACEs, click

Apply

.



Table 29-3 Feature History for Service Policies

Feature Name

Modular Policy Framework

Management class map for use with RADIUS accounting traffic

Releases

7.0(1)

7.2(1)

Inspection policy maps

Regular expressions and policy maps

Match any for inspection policy maps

Maximum connections and embryonic connections for management traffic

7.2(1)

7.2(1)

8.0(2)

8.0(2)


Modular Policy Framework was introduced.

The management class map was introduced for use with

RADIUS accounting traffic. The following commands were introduced:

class-map type management

, and

inspect radius-accounting

.

The inspection policy map was introduced. The following command was introduced:

class-map type inspect

.

Regular expressions and policy maps were introduced to be used under inspection policy maps. The following commands were introduced:

class-map type regex

,

regex

,

match regex

.

The

match any

keyword was introduced for use with inspection policy maps: traffic can match one or more criteria to match the class map. Formerly, only

match all

was available.

The

set connection

command is now available for a Layer

3/4 management class map, for to-the-security appliance management traffic. Only the

conn-max

and

embryonic-conn-max

keywords are available.

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P

A R T

7

Configuring Access Control


C H A P T E R

30

This chapter describes how to control network access through the adaptive security appliance using access rules, and it includes the following sections:

•

Information About Access Rules, page 30-1

•

•

•

•

•

Licensing Requirements for Access Rules, page 30-6



Configuring Access Rules, page 30-7

Feature History for Access Rules, page 30-13

Note

You use access rules to control network access in both routed and transparent firewall modes. In transparent mode, you can use both access rules (for Layer 3 traffic) and EtherType rules (for Layer 2 traffic).

To access the adaptive security appliance interface for management access, you do not also need an access rule allowing the host IP address. You only need to configure management access according to

Chapter 32, “Configuring Management Access.”

Information About Access Rules

Your access policy is made up of one or more access rules and/or EtherType rules per interface or globally for all interfaces.

You can use access rules in routed and transparent firewall mode to control IP traffic. An access rule permits or denies traffic based on the protocol, a source and destination IP address or network, and optionally the source and destination ports.

For transparent mode only, an EtherType rule controls network access for non-IP traffic. An EtherType rule permits or denies traffic based on the EtherType.


•

•

•

General Information About Rules, page 30-2

Information About Access Rules, page 30-4

Information About EtherType Rules, page 30-5


30-1 OL-20339-01

Chapter 30 Configuring Access Rules


General Information About Rules

This section describes information for both access rules and EtherType rules, and it includes the following topics:

•

Implicit Permits, page 30-2

•

•

•

•

•

Using Access Rules and EtherType Rules on the Same Interface, page 30-2

Rule Order, page 30-2

Implicit Deny, page 30-3

Inbound and Outbound Rules, page 30-3

Using Global Access Rules, page 30-4

Implicit Permits

For routed mode, the following types of traffic are allowed through by default:

•

•

IPv4 traffic from a higher security interface to a lower security interface.


For transparent mode, the following types of traffic are allowed through by default:

•


•

•


ARPs in both directions.

Note

ARP traffic can be controlled by ARP inspection, but cannot be controlled by an access rule.

•

BPDUs in both directions.

For other traffic, you need to use either an access rule (IPv4), an IPv6 access rule (IPv6), or an EtherType rule (non-IPv4/IPv6).

Using Access Rules and EtherType Rules on the Same Interface

You can apply both access rules and EtherType rules to each direction of an interface.

Rule Order

The order of rules is important. When the adaptive security appliance decides whether to forward or drop a packet, the adaptive security appliance tests the packet against each rule in the order in which the rules are listed. After a match is found, no more rules are checked. For example, if you create an access rule at the beginning that explicitly permits all traffic for an interface, no further rules are ever checked.

You can disable a rule by making it inactive.

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Implicit Deny

Interface-specific access rules do not have an implicit deny at the end, but global rules on inbound traffic do have an implicit deny at the end of the list, so unless you explicitly permit it, traffic cannot pass. For example, if you want to allow all users to access a network through the adaptive security appliance except for particular addresses, then you need to deny the particular addresses and then permit all others.

For EtherType rules, the implicit deny does not affect IPv4 or IPv6 traffic or ARPs; for example, if you allow EtherType 8037 (the EtherType for IPX), the implicit deny at the end of the list does not block any

IP traffic that you previously allowed with an access rule (or implicitly allowed from a high security interface to a low security interface). However, if you

explicitly

deny all traffic with an EtherType rule, then IP and ARP traffic is denied.

Inbound and Outbound Rules

The adaptive security appliance supports two types of access lists:

•

•

Inbound—Inbound access lists apply to traffic as it enters an interface.

Outbound—Outbound access lists apply to traffic as it exits an interface.

Note

“Inbound” and “outbound” refer to the application of an access list on an interface, either to traffic entering the adaptive security appliance on an interface or traffic exiting the adaptive security appliance on an interface. These terms do not refer to the movement of traffic from a lower security interface to a higher security interface, commonly known as inbound, or from a higher to lower interface, commonly known as outbound.

An inbound access list can bind an access list to a specific interface or apply a global rule on all interfaces. For more information about global rules, see the

“Using Global Access Rules” section on page 30-4

.

An outbound access list is useful, for example, if you want to allow only certain hosts on the inside networks to access a web server on the outside network. Rather than creating multiple inbound access lists to restrict access, you can create a single outbound access list that allows only the specified hosts.

(See Figure 30-1

.) The outbound access list prevents any other hosts from reaching the outside network.

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30-3



Figure 30-1 Outbound Access List

Web Server:

209.165.200.225

Security appliance

Outside

ACL Outbound

Permit HTTP from 209.165.201.4

, 209.165.201.6

, and 209.165.201.

8 to 209.165.200.225

Deny all others

Inside

ACL Inbound

Permit from any to any

HR

ACL Inbound


Eng

ACL Inbound


10.1.1.14

209.165.201.4

Static NAT

10.1.2.67

209.165.201.6

Static NAT

10.1.

3 .

3 4

Static NAT

209.165.201.

8

Using Global Access Rules

Global access rules allow you to apply a global rule to ingress traffic without the need to specify an interface to which the rule must be applied. Using global access rules provides the following benefits:

•

•

When migrating to the adaptive security appliance from a competitor appliance, you can maintain a global access rule policy instead of needing to apply an interface-specific policy on each interface.

Global access control policies are not replicated on each interface, so they save memory space.

•

•

Global access rules provides flexibility in defining a security policy. You do not need to specify which interface a packet comes in on, as long as it matches the source and destination IP addresses.

Global access rules use the same mtrie and stride tree as interface-specific access rules, so scalability and performance for global rules are the same as for interface-specific rules.

You can configure global access rules in conjunction with interface access rules, in which case, the specific interface access rules are always processed before the general global access rules.


This section describes information about access rules and includes the following topics:

•

•

Access Rules for Returning Traffic, page 30-5

Allowing Broadcast and Multicast Traffic through the Transparent Firewall Using Access Rules, page 30-5

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•

Management Access Rules, page 30-5

Access Rules for Returning Traffic

For TCP and UDP connections for both routed and transparent mode, you do not need an access rule to allow returning traffic because the adaptive security appliance allows all returning traffic for established, bidirectional connections.

For connectionless protocols such as ICMP, however, the adaptive security appliance establishes unidirectional sessions, so you either need access rules to allow ICMP in both directions (by applying access lists to the source and destination interfaces), or you need to enable the ICMP inspection engine.

The ICMP inspection engine treats ICMP sessions as bidirectional connections.

Allowing Broadcast and Multicast Traffic through the Transparent Firewall Using Access Rules

In routed firewall mode, broadcast and multicast traffic is blocked even if you allow it in an access rule, including unsupported dynamic routing protocols and DHCP (unless you configure DHCP relay).

Transparent firewall mode can allow any IP traffic through. This feature is especially useful in multiple context mode, which does not allow dynamic routing, for example.

Note

Because these special types of traffic are connectionless, you need to apply an extended access list to both interfaces, so returning traffic is allowed through.

Table 30-1

lists common traffic types that you can allow through the transparent firewall.

Table 30-1 Transparent Firewall Special Traffic

Traffic Type

DHCP

Protocol or Port

UDP ports 67 and 68

EIGRP

OSPF

Protocol 88

Protocol 89

Multicast streams The UDP ports vary depending on the application.

RIP (v1 or v2) UDP port 520

Notes

If you enable the DHCP server, then the adaptive security appliance does not pass DHCP packets.

—

—

Multicast streams are always destined to a

Class D address (224.0.0.0 to 239.x.x.x).

—

Management Access Rules

You can configure access rules that control management traffic destined to the adaptive security appliance. Access control rules for to-the-box management traffic (such as HTTP, Telnet, and SSH) have higher precedence than an management access rule. Therefore, such permitted management traffic will be allowed to come in even if explicitly denied by the to-the-box access list.

Information About EtherType Rules

This section describes EtherType rules and includes the following topics:

•

Supported EtherTypes, page 30-6

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30-5


Licensing Requirements for Access Rules

•

•

Access Rules for Returning Traffic, page 30-6

Allowing MPLS, page 30-6

Supported EtherTypes

•

•

•

•

•

An EtherType rule controls any EtherType identified by a 16-bit hexadecimal number.

EtherType rules support Ethernet V2 frames.

802.3-formatted frames are not handled by the rule because they use a length field as opposed to a type field.

BPDUs, which are permitted by default, are the only exception: they are SNAP-encapsulated, and the adaptive security appliance is designed to specifically handle BPDUs.

The adaptive security appliance receives trunk port (Cisco proprietary) BPDUs. Trunk BPDUs have

VLAN information inside the payload, so the adaptive security appliance modifies the payload with the outgoing VLAN if you allow BPDUs.

Access Rules for Returning Traffic

Because EtherTypes are connectionless, you need to apply the rule to both interfaces if you want traffic to pass in both directions.

Allowing MPLS

If you allow MPLS, ensure that Label Distribution Protocol and Tag Distribution Protocol TCP connections are established through the adaptive security appliance by configuring both MPLS routers connected to the adaptive security appliance to use the IP address on the adaptive security appliance interface as the router-id for LDP or TDP sessions. (LDP and TDP allow MPLS routers to negotiate the labels (addresses) used to forward packets.)

On Cisco IOS routers, enter the appropriate command for your protocol, LDP or TDP. The

interface

is the interface connected to the adaptive security appliance.

hostname(config)#

mpls ldp router-id

interface

force

Or hostname(config)#

tag-switching tdp router-id

interface

force

Licensing Requirements for Access Rules


Model

All models


Base License.

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IPv6 Guidelines

Supports IPv6


To access the adaptive security appliance interface for management access, you do not need an access list allowing the host IP address. You only need to configure management access by following the instructions in

Chapter 32, “Configuring Management Access.”


See the

“Implicit Permits” section on page 30-2

.



•

Adding an Access Rule, page 30-7

•

•

Adding an EtherType Rule (Transparent Mode Only), page 30-8

Configuring Management Access Rules, page 30-10

Adding an Access Rule

To apply an access rule, perform the following steps.

Step 1

Step 2

Step 3

Step 4

Choose

Configuration

>

Firewall

>

Access Rules

.

Click

Add

, and choose one of the following options:

•

•

Add Access Rule

Add IPv6 Access Rule

The appropriate access rule dialog box appears.

From the Interface drop-down list, choose the interface on which to apply the rule.


In the Action field, click one of the following radio buttons next to the desired action:

• Permit



OL-20339-01 30-7



Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Step 12

•

Deny


In the Source field, enter an IP address that specifies the network, interface IP, or any address from which traffic is permitted or denied to the specified destination.

For more information about enabling IPv6 on an interface, see

Chapter 8, “Configuring Interfaces.”

In the Destination field, enter an IP address that specifies the network, interface IP, or any address to which traffic is permitted or denied from the source specified in the Source field.

Select the service type.

(Optional) To add a time range to your access rule that specifies when traffic can be allowed or denied, click

More Options

to expand the list.

a.

To the right of the Time Range drop down list, click the browse button.

b.

c.

d.

e.

The Browse Time Range dialog box appears.

Click

Add

.

The Add Time Range dialog box appears.


Choose the Start Time and the End Time.

To specify additional time constraints for the time range, such as specifying the days of the week or the recurring weekly interval in which the time range will be active, click

Add

, and choose the specifications.

f.

Click

OK

to apply the optional time range specifications.

(Optional) In the Description field, add a text description about the access rule.

The description can contain multiple lines; however, each line can be no more than 100 characters in length.

(Optional) Logging is enabled by default. You can disable logging by unchecking the check box, or you can change the logging level from the drop-down list. The default logging level is Informational.

Click

OK

. The access rule appears with the newly configured access rules.

Click

Apply

to save the access rule to your configuration.

Note

After you add access rules, you can click the following radio buttons to filter which access rules appear in the main pane: IPv4 and IPv6, IPv4 Only, or IPv6 Only.

Adding an EtherType Rule (Transparent Mode Only)

The EtherType Rules window shows access rules based on packet EtherTypes. EtherType rules are used to configure non-IP related traffic policies through the adaptive security appliance when operating in transparent mode. In transparent mode, you can apply both extended and EtherType access rules to an interface. EtherType rules take precedence over the extended access rules.

For more information about EtherType rules, see the

“Information About Access Rules” section on page 30-1 .

To add an EtherType rule, perform the following steps:

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Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Choose

Configuration

>


>

Management Access

>

EtherType Rules

.

Click

Add

.

The Add EtherType rules window appears.

(Optional) To specify the placement of the new EtherType rule, select an existing rule, and click

Insert...

to add the EtherType rule before the selected rule, or click

Insert After...

to add the EtherType rle after the selected rule.

From the Interface drop-down list, choose the interface on which to apply the rule


In the Action field, click one of the following radio buttons next to the desired action:

•

•

Permit


Deny


In the EtherType field, choose an EtherType value from the drop-down list.

(Optional) In the Description field, add a test description about the rule.

The description can contain multiple lines; however, each line can b no more than 100 characters in length.

(Optional) To specify the direction for this rule, click More Options to expand the list, and then specify the direction by clicking one of the following radio buttons:

•

•

In

—Incoming traffic

Out

—Outgoing traffic

Click

OK

.

OL-20339-01

Fields

•

Add—Adds a new EtherType rule. Choose the type of rule you want to add from the drop-down list.

•

Edit—Edits an EtherType rule.

•

•

•

•

•

Delete—Deletes an EtherType rule.

Move Up—Moves a rule up. Rules are assessed in the order they appear in this table, so the order can matter if you have overlapping rules.

Move Down—Moves a rule down.

Cut—Cuts a rule.

•

Copy—Copies the parameters of a rule so you can start a new rule with the same parameters using the Paste button.

Paste—Opens an Add/Edit Rule dialog box with the copied or cut parameters of the rule prefilled.

You can then make any modifications and add it to the table. The Paste button adds the rule above the selected rule. The Paste After item, available from the Paste drop-down list, adds the rule after the selected rule.

The following description summarizes the columns in the EtherType Rules table. You can edit the contents of these columns by double-clicking on a table cell. Double-clicking on a column header sorts the table in ascending alphanumeric order, using the selected column as the sort key. If you right-click a rule, you see all of the options represented by the buttons above, as well as Insert and Insert After items.

These items either insert a new rule before the selected rule (Insert) or after the selected rule (Insert

After.)


30-9



•

•

•

•

•

•

No—Indicates the order of evaluation for the rule.

Action—Permit or deny action for this rule.

Ethervalue—EtherType value: IPX, BPDU, MPLS-Unicast, MPLS-Multicast, or a 16-bit hexadecimal value between 0x600 (1536) and 0xffff by which an EtherType can be identified.

Interface—Interface to which the rule is applied.

Direction Applied—Direction for this rule: incoming traffic or outgoing traffic.

Description—Optional text description of the rule.

Add/Edit EtherType Rule

The Add/Edit EtherType Rules dialog box lets you add or edit an EtherType rule.

For more information about EtherType rules, see the


Fields

•

Action—Permit or deny action for this rule.

•

•

•

Interface—Interface name for this rule.

Apply rule to—Direction for this rule: incoming traffic or outgoing traffic.

•

Ethervalue—EtherType value: BPDU, IPX, MPLS-Unicast, MPLS-Multicast, any (any value between 0x600 and 0xffff), or a 16-bit hexadecimal value between 0x600 (1536) and 0xffff by which an EtherType can be identified.

Description—Optional text description of the rule.

Configuring Management Access Rules

Access Rules specifically permit or deny traffic to or from a particular peer (or peers), while

Management Access Rules provide access control for to-the-box traffic. For example, in addition to detecting IKE Denial of Service attacks, you can block them using management access rules.

To add a Management Access Rule, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Choose

Configuration

>


>

Management Access

>

Management Access Rules

.

Click

Add

, and choose one of the following actions:

•

Add Management Access Rule

• Add IPv6 Management Access Rule

The appropriate Add Management Access Rule dialog box appears.

From the Interface drop-down list, choose an interface on which to apply the rule.

In the Action field, click one of the following:

•

•

Permit

(permits this traffic)

Deny

(denies this traffic)

In the Source field, choose Any, or click the ellipsis (...) to browse for an address.

In the Service field, add a service name for rule traffic, or click the ellipsis (...) to browse for a service.

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Step 7

Step 8

Step 9

Step 10

Step 11

(Optional) In the Description field, add a description for this management access rule.

(Optional) If you want to receive log messages for this access rule, check

Enable Logging

, and then from the Logging Level drop-down list, choose the log level to apply. The default level is Informational.

(Optional) To configure advanced options, click

More Options

to configure the following settings:

•

•

If you want to turn off this Management Access Rule, uncheck

Enable Rule

.

Add a source service in the Source Service field, or click the ellipsis (...) to browse for a service.

•

•

The destination service and source service must be the same. Copy and paste the destination Service field to the Source Service field.

To configure the logging interval (if you enable logging and choose a non-default setting), enter a value in seconds in the Logging Interval field.

To select a predefined time range for this rule, from the Time Range drop-down list, choose a time range; or click the ellipsis (...) to browse for a time range.

The Add Time Range dialog box appears. For information about adding a time range, see the

“Configuring Time Ranges” section on page 13-15 .

Click

OK

. The dialog box closes and the Management Access rule is added.

Click

Apply

. The rule is saved in the running configuration.

Note

After you create management access rules, you can click the radio buttons at the bottom of the pane to sort the display and show both IPv4 and IPv6 rules, IPv4 only, or IPv6 only.

Advanced Access Rule Configuration

The Advanced Access Rule Configuration dialog box lets you set access rule logging options.

When you enable logging, if a packet matches the access rule, the adaptive security appliance creates a flow entry to track the number of packets received within a specific interval. The adaptive security appliance generates a system log message at the first hit and at the end of each interval, identifying the total number of hits during the interval and reporting the time of the last hit.

Note

The adaptive security appliancepane displays the hit count information in the “last rule hit” row. To view the rule hit count and timestamp, choose

Configuration

>

Firewall

>

Advanced

>

ACL Manager

, and hover the mouse pointer over a cell in the ACL Manager table.

At the end of each interval, the adaptive security appliance resets the hit count to 0. If no packets match the access rule during an interval, the adaptive security appliance deletes the flow entry.

A large number of flows can exist concurrently at any point of time. To prevent unlimited consumption of memory and CPU resources, the adaptive security appliance places a limit on the number of concurrent deny flows; the limit is placed only on deny flows (and not permit flows) because they can indicate an attack. When the limit is reached, the adaptive security appliance does not create a new deny flow until the existing flows expire. If someone initiates a denial of service attack, the adaptive security appliance can create a very large number of deny flows in a very short period of time. Restricting the number of deny-flows prevents unlimited consumption of memory and CPU resources.

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Prerequisites

These settings only apply if you enable the newer logging mechanism for the access rule.

Fields

•

Maximum Deny-flows—The maximum number of deny flows permitted before the adaptive security appliance stops logging, between 1 and the default value. The default is 4096.

•

•

Alert Interval—The amount of time (1-3600 seconds) between system log messages (number

106101) that identify that the maximum number of deny flows was reached. The default is 300 seconds.

Per User Override table—Specifies the state of the per user override feature. If the per user override feature is enabled on the inbound access rule, the access rule provided by a RADIUS server replaces the access rule configured on that interface. If the per user override feature is disabled, the access rule provided by the RADIUS server is combined with the access rule configured on that interface.

If the inbound access rule is not configured for the interface, per user override cannot be configured.

•

Object Group Search Setting—Reduces the amount of memory used to store service rules, but lengthens the amount of time to search for a matching access rule.

Access Rule Explosion

The security appliance allows you to turn off the expansion of access rules that contain certain object groups. When expansion is turned off, an object group search is used for lookup, which lowers the memory requirements for storing expanded rules but decreases the lookup performance. Because of the trade-off of performance for memory utilization, you can turn on and turn off the search.

To configure the option of turning off the expansion of access rules that contain s, perform the following steps:

Step 1

Step 2

Step 3

Choose

Configuration

>

Firewall

>

Access Rules

.

Click the

Advanced

button.

Check the

Enable Object Group Search Algorithm

check box.

For more information about access rules, see the


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Feature History for Access Rules


Table 30-2


Table 30-2 Feature History for Access Rules

Feature Name

Interface access rules.

Platform

Releases

7.0(1)

Global access rules.

8.3(1)


Controlling network access through the security appliance using access lists.


Firewall > Access Rules.

Global access rules were introduced.


Firewall > Access Rules.

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C H A P T E R

31

Configuring AAA Servers and the Local Database

This chapter describes support for AAA

( pronounced “triple A”) and how to configure AAA servers and the local database.


•

•

•

•

•

•

•

•

•

•

AAA Overview, page 31-1

AAA Server and Local Database Support, page 31-3

Configuring AAA Server Groups, page 31-8

Testing Server Authentication and Authorization, page 31-18

Adding a User Account, page 31-18

Configuring LDAP Attribute Maps, page 31-22

Adding an Authentication Prompt, page 31-23

AAA Servers Monitoring, page 31-24


Feature History for AAA Servers, page 31-26

AAA Overview

AAA enables the adaptive security appliance to determine who the user is (authentication), what the user can do (authorization), and what the user did (accounting).

AAA provides an extra level of protection and control for user access than using access lists alone. For example, you can create an access list allowing all outside users to access Telnet on a server on the DMZ network. If you want only some users to access the server and you might not always know IP addresses of these users, you can enable AAA to allow only authenticated and/or authorized users to connect through the adaptive security appliance. (The Telnet server enforces authentication, too; the adaptive security appliance prevents unauthorized users from attempting to access the server.)

You can use authentication alone or with authorization and accounting. Authorization always requires a user to be authenticated first. You can use accounting alone, or with authentication and authorization.


•

About Authentication, page 31-2

•

•

About Authorization, page 31-2

About Accounting, page 31-3

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31-1

Chapter 31 Configuring AAA Servers and the Local Database

AAA Overview

About Authentication

Authentication controls access by requiring valid user credentials, which are usually a username and password. You can configure the adaptive security appliance to authenticate the following items:

•

All administrative connections to the adaptive security appliance including the following sessions:

–

–

Telnet

SSH

•

•

•

–

–

Serial console

ASDM using HTTPS

–

VPN management access

The

enable

command

Network access

VPN access

About Authorization

Authorization controls access

per user

after users are authenticated. You can configure the adaptive security appliance to authorize the following items:

•

Management commands

•

•

Network access

VPN access

Authorization controls the services and commands that are available to each authenticated user. If you did not enable authorization, authentication alone would provide the same access to services for all authenticated users.

If you need the control that authorization provides, you can configure a broad authentication rule, and then have a detailed authorization configuration. For example, you can authenticate inside users who attempt to access any server on the outside network and then limit the outside servers that a particular user can access using authorization.

The adaptive security appliance caches the first 16 authorization requests per user, so if the user accesses the same services during the current authentication session, the adaptive security appliance does not resend the request to the authorization server.

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AAA Server and Local Database Support

About Accounting

Accounting tracks traffic that passes through the adaptive security appliance, enabling you to have a record of user activity. If you enable authentication for that traffic, you can account for traffic per user.

If you do not authenticate the traffic, you can account for traffic per IP address. Accounting information includes session start and stop times, username, the number of bytes that pass through the adaptive security appliance for the session, the service used, and the duration of each session.


The adaptive security appliance supports a variety of AAA server types and a local database that is stored on the adaptive security appliance. This section describes support for each AAA server type and the local database, and includes the following topics:

•

Summary of Support, page 31-3

•

•

•

•

•

RADIUS Server Support, page 31-4

TACACS+ Server Support, page 31-5

RSA/SDI Server Support, page 31-5

NT Server Support, page 31-6

•

•

•

Kerberos Server Support, page 31-6

LDAP Server Support, page 31-7

HTTP Forms Authentication for Clientless SSL VPN, page 31-7

Local Database Support, page 31-7

Summary of Support

Table 31-1

summarizes the support for each AAA service by each AAA server type, including the local database. For more information about support for a specific AAA server type, see the topics following the table.

Table 31-1 Summary of AAA Support

Database Type

Local RADIUS TACACS+ SDI (RSA) NT Kerberos LDAP HTTP Form AAA Service

Authentication of...

VPN users

1

Firewall sessions

Administrators

Authorization of...

VPN users

Firewall sessions

Administrators

Accounting of...

Yes Yes

Yes Yes

Yes Yes

Yes Yes

No Yes

4

Yes

5

No

Yes

Yes

Yes

No

Yes

Yes

Yes

Yes

Yes

3

No

No

No

Yes Yes

Yes Yes

Yes Yes

No No

No No

No No

Yes

Yes

Yes

Yes

No

No

No

No

No

Yes

2

No

No

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Table 31-1 Summary of AAA Support (continued)

AAA Service

VPN connections

Firewall sessions

Administrators

Database Type

Local RADIUS TACACS+ SDI (RSA) NT Kerberos LDAP HTTP Form

No

No

No

Yes

Yes

Yes

6

Yes

Yes

Yes

No

No

No

No

No

No

No

No

No

No

No

No

No

No

No

1.

For SSL VPN connections, either PAP or MS-CHAPv2 can be used.

2.

HTTP Form protocol supports both authentication and single sign-on operations for clientless SSL VPN users sessions only.

3.

RSA/SDI is supported for ASDM HTTP administrative access with ASA5500 software version 8.2(1) or later.

4.

For firewall sessions, RADIUS authorization is supported with user-specific access lists only, which are received or specified in a RADIUS authentication response.

5.

Local command authorization is supported by privilege level only.

6.

Command accounting is available for TACACS+ only.

Note

In addition to the native protocol authentication listed in table Table 1-1, the adaptive security appliance supports proxying authentication. For example, the adaptive security appliance can proxy to an RSA/SDI and/or LDAP server via a RADIUS server. Authentication via digital certificates and/or digital certificates with the AAA combinations listed in the table are also supported.

RADIUS Server Support

The adaptive security appliance supports the following RADIUS servers for AAA, in addition to the one available on the adaptive security appliance itself:

•

•

Cisco Secure ACS 3.2, 4.0, 4.1

RSA RADIUS in RSA Authentication Manager 5.2 and 6.1

Authentication Methods

The adaptive security appliance supports the following authentication methods with RADIUS:

•

PAP—For all connection types.

•

•

•

CHAP and MS-CHAPv1—For L2TP-over-IPsec connections.

MS-CHAPv2—For L2TP-over-IPsec connections, and for regular IPsec remote access connections when the password management feature is enabled. You can also use MS-CHAPv2 with clientless connections.

Authentication Proxy modes—Including RADIUS to Active Directory, RADIUS to RSA/SDI,

RADIUS to Token-server, and RSA/SI to RADIUS connections,

Note

To enable MS-CHAPv2 as the protocol used between the adaptive security appliance and the RADIUS server for a VPN connection, password management must be enabled in the tunnel group general attributes. Enabling password management generates an MS-CHAPv2 authentication request from the adaptive security appliance to the RADIUS server. See the description of the

password-management

command for details.

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If you use double authentication and enable password management in the tunnel group, then the primary and secondary authentication requests include MS-CHAPv2 request attributes. If a RADIUS server does not support MS-CHAPv2, then you can configure that server to send a non-MS-CHAPv2 authentication request by using the

no mschapv2-capable

command.

Attribute Support

•

•

•

•

•

The adaptive security appliance supports the following sets of RADIUS attributes:

•

Authentication attributes defined in RFC 2138.

Accounting attributes defined in RFC 2139.

RADIUS attributes for tunneled protocol support, defined in RFC 2868.

Cisco IOS VSAs, identified by RADIUS vendor ID 9.

Cisco VPN-related VSAs, identified by RADIUS vendor ID 3076.

•

Microsoft VSAs, defined in RFC 2548.

Cisco VSA (Cisco-Priv-Level), which provides a standard 0-15 numeric ranking of privileges, with

1 being the lowest level and 15 being the highest level. A zero level indicates no privileges. The first level (login) allows privileged EXEC access for the commands available at this level. The second level (enable) allows CLI configuration privileges.

RADIUS Authorization Functions

The adaptive security appliance can use RADIUS servers for user authorization for network access using dynamic access lists or access list names per user. To implement dynamic access lists, you must configure the RADIUS server to support it. When the user authenticates, the RADIUS server sends a downloadable access list or access list name to the adaptive security appliance. Access to a given service is either permitted or denied by the access list. The adaptive security appliance deletes the access list when the authentication session expires.

TACACS+ Server Support

The adaptive security appliance supports TACACS+ authentication with ASCII, PAP, CHAP, and

MS-CHAPv1.

RSA/SDI Server Support

The RSA SecureID servers are also known as SDI servers.


•

RSA/SDI Version Support, page 31-6

•

•

Two-step Authentication Process, page 31-6

RSA/SDI Primary and Replica Servers, page 31-6

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RSA/SDI Version Support

The adaptive security appliance supports SDI Versions 5.0 and 6.0. SDI uses the concepts of an SDI primary and SDI replica servers. Each primary and its replicas share a single node secret file. The node secret file has its name based on the hexadecimal value of the ACE/Server IP address with .sdi appended.

A version 5.0 or 6.0 SDI server that you configure on the adaptive security appliance can be either the

primary or any one of the replicas. See the “RSA/SDI Primary and Replica Servers” section on page 31-6

for information about how the SDI agent selects servers to authenticate users.

Two-step Authentication Process

SDI Versions 5.0 and 6.0 use a two-step process to prevent an intruder from capturing information from an RSA SecurID authentication request and using it to authenticate to another server. The agent first sends a lock request to the SecurID server before sending the user authentication request. The server locks the username, preventing another (replica) server from accepting it. This actions means that the same user cannot authenticate to two adaptive security appliances using the same authentication servers simultaneously. After a successful username lock, the adaptive security appliance sends the passcode.

RSA/SDI Primary and Replica Servers

The adaptive security appliance obtains the server list when the first user authenticates to the configured server, which can be either a primary or a replica. The adaptive security appliance then assigns priorities to each of the servers on the list, and subsequent server selection derives at random from those assigned priorities. The highest priority servers have a higher likelihood of being selected.

NT Server Support

The adaptive security appliance supports Microsoft Windows server operating systems that support

NTLM Version 1, collectively referred to as NT servers.

Note

NT servers have a maximum length of 14 characters for user passwords. Longer passwords are truncated, which is a limitation of NTLM Version 1.

Kerberos Server Support

The adaptive security appliance supports 3DES, DES, and RC4 encryption types.

Note

The adaptive security appliance does not support changing user passwords during tunnel negotiation. To avoid this situation happening inadvertently, disable password expiration on the Kerberos/Active

Directory server for users connecting to the adaptive security appliance.

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LDAP Server Support

The adaptive security appliance supports LDAP. For detailed information, see the “Configuring LDAP

Attribute Maps” section on page 31-22

.

HTTP Forms Authentication for Clientless SSL VPN

The adaptive security appliance can use the HTTP Form protocol for both authentication and single sign-on (SSO) operations of Clientless SSL VPN user sessions only.

Local Database Support

The adaptive security appliance maintains a local database that you can populate with user profiles.


•

•

User Profiles, page 31-7

Fallback Support, page 31-7

User Profiles

User profiles include, at a minimum, a username. Typically, a password is assigned to each username, although passwords are optional.

Fallback Support

The local database can act as a fallback method for several functions. This behavior is designed to help you prevent accidental lockout from the adaptive security appliance.

For users who need fallback support, we recommend that their usernames and passwords in the local database match their usernames and passwords in the AAA servers. This practice provides transparent fallback support. Because the user cannot determine whether a AAA server or the local database is providing the service, using usernames and passwords on AAA servers that are different than the usernames and passwords in the local database means that the user cannot be certain which username and password should be given.

The local database supports the following fallback functions:

•

Console and enable password authentication—When you use the

aaa authentication console

command, you can add the

LOCAL

keyword after the AAA server group tag. If the servers in the group are all unavailable, the adaptive security appliance uses the local database to authenticate administrative access, which can also include enable password authentication.

•

•

Command authorization—When you use the

aaa authorization

command, you can add the

LOCAL

keyword after the AAA server group tag. If the TACACS+ servers in the group are all unavailable, the local database is used to authorize commands based on privilege levels.

VPN authentication and authorization—VPN authentication and authorization are supported to enable remote access to the adaptive security appliance if AAA servers that normally support these

VPN services are unavailable. The

authentication-server-group

command, available in tunnel-group general attributes mode, lets you specify the

LOCAL

keyword when you are configuring attributes of a tunnel group. When a VPN client of an administrator specifies a tunnel

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31-7


Configuring AAA Server Groups

group configured to fallback to the local database, the VPN tunnel can be established even if the

AAA server group is unavailable, provided that the local database is configured with the necessary attributes.


If you want to use an external AAA server for authentication, authorization, or accounting, you must first create at least one AAA server group per AAA protocol and add one or more servers to each group. You identify AAA server groups by name. Each server group is specific to one type of server: Kerberos,

LDAP, NT, RADIUS, SDI, or TACACS+.

You can have up to 100 server groups in single mode or 4 server groups per context in multiple mode.

Each group can have up to 16 servers in single mode or 4 servers in multiple mode. When a user logs in, the servers are accessed one at a time starting with the first server that you specify in the configuration, until a server responds. If all servers in the group are unavailable, the adaptive security appliance tries the local database if you configured it as a fallback method (management authentication and authorization only). If you do not have a fallback method, the adaptive security appliance continues to try the AAA servers.

How Fallback Works with Multiple Servers in a Group

If you configure multiple servers in a server group and you enable fallback to the local database for the server group, fallback occurs when no server in the group responds to the authentication request from the adaptive security appliance. To illustrate this further, consider this scenario:

You configure an LDAP server group with two Active Directory servers, server 1 and server 2, in that order. When the remote user logs in, the adaptive security appliance attempts to authenticate to server 1.

If server 1 responds with an authentication failure (such as user not found), the adaptive security appliance does not attempt to authenticate to server 2.

If server 1 does not respond within the timeout period (or the number of authentication attempts exceeds the configured maximum), the adaptive security appliance tries server 2.

If both servers in the group do not respond, and the adaptive security appliance is configured to fallback to the local database, the adaptive security appliance attempts to authenticate to the local database.


•

•

•

Adding a Server Group, page 31-8

Adding a Server to a Group, page 31-10

AAA Server Parameters, page 31-10

Adding a Server Group

To add a server group, perform the following steps:

Step 1

Step 2

Choose

Configuration

>


>

Users/AAA

>

AAA Server Groups

.

In the AAA Server Groups area, click

Add

.

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Step 3

Step 4

Step 5

The Add AAA Server Group dialog box appears.

In the Server Group field, add a name for the group.

From the Protocol drop-down list, choose the server type:

•

•

•

•

•

•

RADIUS

TACACS+

SDI

NT Domain

Kerberos

LDAP

•

HTTP Form

In the Accounting Mode field, click the radio button for the mode you want to use (

Simultaneous

or

Single

).

In Single mode, the adaptive security appliance sends accounting data to only one server.

In Simultaneous mode, the adaptive security appliance sends accounting data to all servers in the group.

Note

This option is not available for the following protocols: HTTP Form, SDI, NT, Kerberos, and

LDAP.

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

In the Reactivation Mode field, click the radio button for the mode you want to use (

Depletion

or

Timed

).

In Depletion mode, failed servers are reactivated only after all of the servers in the group are inactive.

In Timed mode, failed servers are reactivated after 30 seconds of down time.

If you chose the Depletion reactivation mode, add a time interval in the Dead Time field.

The Dead Time is the duration of time, in minutes, that elapses between the disabling of the last server in a group and the subsequent reenabling of all servers.

In the Max Failed Attempts field, add the number of failed attempts permitted.

This option sets the number of failed connection attempts allowed before declaring a nonresponsive server to be inactive.

(Optional) If you are adding a RADIUS server type, perform the following steps:

a.

Check the

Enable interim accounting update

check box if you want to enable multi-session accounting for clientless SSL and AnyConnect sessions.

b.

Click the

VPN3K Compatibility Option

to expand the list, and click one of the following radio buttons to specify whether or not a downloadable ACL received from RADIUS should be merged with a Cisco AV-pair ACL:

–

Do not merge

–

–

Place the downloadable ACL after Cisco AV-pair ACL

Place the downloadable ACL before Cisco AV-pair ACL

Click

OK

.

The dialog box closes, and the server group is added to the AAA Server Groups table.

In the AAA Server Groups dialog box, click

Apply

to save the changes.

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31-9


The changes are saved to the running configuration.


Adding a Server to a Group

To add a AAA server to a group, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Choose

Configuration

>


>

Users/AAA

>


, and in the AAA

Server Groups area, click the server group to which you want to add a server.

The row is highlighted in the table.

In the Servers in the Selected Group area (lower pane), click

Add

.

The Add AAA Server Group dialog box appears for the server group.

From the Interface Name drop-down list, choose the interface name on which the authentication server resides.

In the Server Name or IP Address field, add either a server name or IP address for the server that you are adding to the group.

In the Timeout field, either add a timeout value or keep the default. The timeout is the duration of time, in seconds, that the adaptive security appliance waits for a response from the primary server before sending the request to the backup server.

The other parameters available depend on the server type. See the following sections for parameters that are unique to each server type:

•

•

•

RADIUS Server Fields, page 31-11

TACACS+ Server Fields, page 31-12

SDI Server Fields, page 31-13

Windows NT Domain Server Fields, page 31-13

•

•

•

Kerberos Server Fields, page 31-13

LDAP Server Fields, page 31-15

•

HTTP Form Server Fields, page 31-17

Click

OK

.

The Add AAA Server Group dialog box closes, and the AAA server is added to the AAA server group.

In the AAA Server Groups pane, click

Apply



AAA Server Parameters

The following sections list the unique fields for each server type when you add a server to a server group:

•

•

•

RADIUS Server Fields, page 31-11

TACACS+ Server Fields, page 31-12

SDI Server Fields, page 31-13

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•

•

Windows NT Domain Server Fields, page 31-13

Kerberos Server Fields, page 31-13

LDAP Server Fields, page 31-15

•

•

HTTP Form Server Fields, page 31-17


“Adding a Server to a Group” section on page 31-10 .

RADIUS Server Fields

The following table describes the unique fields for configuring RADIUS servers, for use with the


Field Description

Server Authentication Port The server port to be used for authentication of users. The default port is 1645.

Server Accounting Port The server port to be used for accounting of users. The default port is

1646.

Retry Interval

Server Secret Key

The duration of time, 1 to 10 seconds, that the adaptive security appliance waits between attempts to contact the server.

The shared secret key used to authenticate the RADIUS server to the adaptive security appliance. The server secret you configure here should match the one configured on the RADIUS server. If you do not know the server secret, ask the RADIUS server administrator. The maximum field length is 64 characters.

Common Password A case-sensitive password that is common among users who access this

RADIUS authorization server through this adaptive security appliance.

Be sure to provide this information to your RADIUS server administrator.

Note

For an authentication RADIUS server (rather than authorization) do not configure a common password.

If you leave this field blank, the users username is the password for accessing this RADIUS authorization server.

Never use a RADIUS authorization server for authentication. Common passwords or usernames as passwords are less secure than assigning unique user passwords.

Note

Although the password is required by the RADIUS protocol and the RADIUS server, users do not need to know it.

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31-11


Field

ACL Netmask Convert


Description

How you want the adaptive security appliance to handle netmasks received in downloadable access lists.

•

Detect automatically: The adaptive security appliance attempts to determine the type of netmask expression used. If the adaptive security appliance detects a wildcard netmask expression, the adaptive security appliance converts it to a standard netmask expression.

Note

Because some wildcard expressions are difficult to detect clearly, this setting may misinterpret a wildcard netmask expression as a standard netmask expression.

•

Standard: The adaptive security appliance assumes downloadable access lists received from the RADIUS server contain only standard netmask expressions. No translation from wildcard netmask expressions is performed.

•

Wildcard: The adaptive security appliance assumes downloadable access lists received from the RADIUS server contain only wildcard netmask expressions, and it converts them all to standard netmask expressions when the access lists are downloaded.

Microsoft CHAPv2 Capable If you use double authentication and enable password management in the tunnel group, then the primary and secondary authentication requests include MS-CHAPv2 request attributes. If a RADIUS server does not support MS-CHAPv2, then you can configure that server to send a non-MS-CHAPv2 authentication request by unchecking this check box.

TACACS+ Server Fields

The following table describes the unique fields for configuring TACACS+ servers, for use with the

“Adding a Server to a Group” section on page 31-10

.

Field

Server Port

Server Secret Key

Description

The port to be used for this server.

The shared secret key used to authenticate the TACACS+ server to the adaptive security appliance. The server secret that you configure here should match the one that is configured on the TACACS+ server. If you do not know the server secret, ask the RADIUS server administrator.

The maximum field length is 64 characters.

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SDI Server Fields

The following table describes the unique fields for configuring SDI servers, for use with the

“Adding a

Server to a Group” section on page 31-10

.

Field

Server Port

Retry Interval

Description

The TCP port number by which this server is accessed.


Windows NT Domain Server Fields

The following table describes the unique fields for configuring Windows NT Domain servers, for use with the


Field

Server Port

Domain Controller

Description

Port number 139, or the TCP port number used by the adaptive security appliance to communicate with the Windows NT server.

The host name (no more than 15 characters) of the NT Primary Domain

Controller for this server (for example, PDC01). You must enter a name, and it must be the correct host name for the server whose IP address you added in the field, Authentication Server Address. If the name is incorrect, authentication fails.

Kerberos Server Fields

The following table describes the unique fields for configuring Kerberos servers, for use with the


Field

Server Port

Description

Server port number 88, or the UDP port number over which the adaptive security appliance communicates with the Kerberos server.

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31-13


Field

Retry Interval

Realm


Description


The name of the Kerberos realm. For example:

•

EXAMPLE.COM

•

•

EXAMPLE.NET

EXAMPLE.ORG

Note

Most Kerberos servers require the realm to be all uppercase for authentication to succeed.

The maximum length is 64 characters. The following types of servers require that you enter the realm name in all uppercase letters:

•

•

•

Windows 2000

Windows XP

Windows.NET

You must enter the correct realm name for the server whose IP address you entered in the Server IP Address field.

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LDAP Server Fields

The following table describes the unique fields for configuring LDAP servers, for use with the

“Adding a Server to a Group” section on page 31-10

.

Field

Enable LDAP over SSL check box

Server Port

Server type

Base DN

Scope

Naming Attribute(s)

Description

When checked, SSL secures communications between the adaptive security appliance and the LDAP server. Also called secure LDAP

(LDAP-S).

Note

If you do not configure the SASL protocol, we strongly recommend that you secure LDAP communications with SSL.

TCP port number 389, the port which the adaptive security appliance uses to access the LDAP server for simple (non-secure) authentication, or TCP port 636 for secure authentication (LDAP-S).

All LDAP servers support authentication and authorization. Only

Microsoft AD and Sun LDAP servers additionally provide a VPN remote access password management capability, which requires

LDAP-S.

A drop-down list for choosing one of the following LDAP server types:

•

•

•

Detect Automatically/Use Generic Type

Microsoft

Novell

OpenLDAP

•

•

Sun

The Base Distinguished Name, or location in the LDAP hierarchy where the server should begin searching when it receives an LDAP request (for example, OU=people, dc=cisco, dc=com).

The extent of the search the server should make in the LDAP hierarchy when it receives an authorization request. The available options are:

•

•

One Level: Searches only one level beneath the Base DN. This option is quicker.

All Levels: Searches all levels beneath the Base DN; in other words, searches the entire subtree hierarchy. This option takes more time.

The Relative Distinguished Name attribute (or attributes) that uniquely identifies an entry on the LDAP server. Common naming attributes are

Common Name (CN), sAMAccountName, userPrincipalName, and

User ID (uid).

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Field

Login DN

Description

The adaptive security appliance uses the Login Distinguished Name

(DN) and Login Password to establish trust (bind) with an LDAP server.

The Login DN represents a user record in the LDAP server that the administrator uses for binding.

When binding, the adaptive security appliance authenticates to the server using the Login DN and the Login password. When performing a

Microsoft Active Directory read-only operation (such as authentication, authorization, or group-search), the adaptive security appliance can bind with a Login DN with fewer privileges. For example, the Login DN can be a user whose AD “Member Of” designation is part of Domain Users.

For VPN password management operations, the Login DN needs elevated privileges and must be part of the Account Operators AD group.

The following is an example of a Login DN: cn=Binduser1,ou=Admins,ou=Users,dc=company_A,dc=com

Login Password

LDAP Attribute Map

SASL MD5 authentication check box

SASL Kerberos authentication

Kerberos Server Group

The adaptive security appliance supports:

•

•

•

•

Simple LDAP authentication with an unencrypted password on port

389

Secure LDAP (LDAP-S) on port 636

Simple Authentication and Security Layer (SASL) MD5

SASL Kerberos

The adaptive security appliance does not support anonymous authentication.

The password for the Login DN user account. The characters you type are replaced with asterisks.

The LDAP attribute maps that you can apply to LDAP server. Used to map Cisco attribute names to user-defined attribute names and values.

See the

“Configuring LDAP Attribute Maps” section on page 31-22 .

When checked, the MD5 mechanism of the SASL authenticates communications between the adaptive security appliance and the LDAP server.

When checked, the Kerberos mechanism of the SASL secures authentication communications between the adaptive security appliance and the LDAP server.

The Kerberos server or server group used for authentication. The

Kerberos Server group option is disabled by default and is enabled only when SASL Kerberos authentication is chosen.

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Field

Group Base DN

Group Search Timeout


Description

Used only for Active Directory servers using LDAP protocol. This DN specifies the location in the LDAP hierarchy to begin searching for the

AD groups (that is, the list of memberOf enumerations). If this field is not configured, the adaptive security appliance uses the Base DN for AD group retrieval.

ASDM uses the list of retrieved AD groups to define AAA selection criteria for dynamic access policies. For more information, see the

show ad-groups

command.

Specifies the maximum time to wait for a response from an AD server that was queried for available groups.

HTTP Form Server Fields

This area appears only when the selected server group uses HTTP Form, and only the server group name and the protocol are visible. Other fields are not available when using HTTP Form.

If you do not know what the following parameters are, use an HTTP header analyzer to extract the data from the HTTP GET and POST exchanges when logging into the authenticating web server directly, not through the adaptive security appliance.

The following table describes the unique fields for configuring HTTP Form servers, for use with the


Field

Start URL

Action URI

Username

Password

Description

The complete URL of the authenticating web server location where a pre-login cookie can be retrieved. This parameter must be configured only when the authenticating web server loads a pre-login cookie with the login page. A drop-down list offers both HTTP and HTTPS. The maximum number of characters is 1024, and there is no minimum.

The complete Uniform Resource Identifier for the authentication program on the authorizing web server. The maximum number of characters for the complete URI is 2048 characters.

The name of a username parameter—not a specific username—that must be submitted as part of the HTTP form used for SSO authentication. The maximum number of characters is 128, and there is no minimum.

The name of a user password parameter—not a specific password value—that must be submitted as part of the HTTP form used for SSO authentication. The maximum number of characters is 128, and there is no minimum.

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Testing Server Authentication and Authorization

Field

Hidden Values

Description

The hidden parameters for the HTTP POST request submitted to the authenticating web server for SSO authentication. This parameter is necessary only when it is expected by the authenticating web server as indicated by its presence in the HTTP POST request. The maximum number of characters is 2048.

Authentication Cookie Name (Optional) The name of the cookie that is set by the server on successful login and that contains the authentication information. It is used to assign a meaningful name to the authentication cookie to help distinguish it from other cookies that the web server may pass back. The maximum number of characters is 128, and there is no minimum.

Testing Server Authentication and Authorization

To determine whether the adaptive security appliance can contact an AAA server and authenticate or authorize a user, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

From the Configuration > Device Management > Users/AAA > AAA Server Groups > AAA Server

Groups table, click the server group in which the server resides.


From the Servers in the Selected Group table, click the server that you want to test.


Click

Test

.

The Test AAA Server dialog box appears for the selected server.

Click the type of test you want to perform—

Authentication

or

Authorization

.

In the Username field, add a username.

If you are testing authentication, in the Password field, add the password for the username.

Click

OK

.

The adaptive security appliance sends an authentication or authorization test message to the server. If the test fails, ASDM displays an error message.

Adding a User Account

The local database is used for the following features:

•

ASDM per-user access

By default, you can log into ASDM with a blank username and the enable password (see the

“Configuring the Hostname, Domain Name, and Passwords” section on page 9-1

). However, if you enter a username and password at the login screen (instead of leaving the username blank), ASDM checks the local database for a match.

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Note

Although you can configure HTTP authentication using the local database, that functionality is always enabled by default. You should only configure HTTP authentication if you want to use a

RADIUS or TACACS+ server for authentication.

•

•

•

•

Console authentication

Telnet and SSH authentication

enable

command authentication

This setting is for CLI-access only and does not affect the ASDM login.

Command authorization

If you turn on command authorization using the local database, then the adaptive security appliance refers to the user privilege level to determine which commands are available. Otherwise, the privilege level is not generally used. By default, all commands are either privilege level 0 or level

15. ASDM allows you to enable three predefined privilege levels, with commands assigned to level

15 (Admin), level 5 (Read Only), and level 3 (Monitor Only). If you use the predefined levels, then assign users to one of these three privilege levels.

Network access authentication

•

•

VPN client authentication

You cannot use the local database for network access authorization.

For multiple context mode, you can configure usernames in the system execution space to provide individual logins at the CLI using the

login

command; however, you cannot configure any AAA rules that use the local database in the system execution space.

To add a user account to the adaptive security appliance local database, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Choose

Configuration > Device Management > Users/AAA > User Accounts

, and then click

Add

.

The Add User Account-Identity dialog box appears.

In the Username field, add a username from 4 to 64 characters long.

In the Password field, add a password between 3 and 32 characters. Entries are case-sensitive. The field displays only asterisks. To protect security, we recommend a password length of at least 8 characters.

In the Confirm Password field, add the password again.

For security purposes, only asterisks appear in the password fields.

To enable MSCHAP authentication, check

User authenticated using MSCHAP

.

This option specifies that the password is converted to Unicode and hashed using MD4 after you enter it. Use this feature if users are authenticated using MSCHAPv1 or MSCHAPv2.

To specify the VPN groups that the user belongs to, enter a group name in the Member of field, and click

Add

.

To delete a VPN group, choose the group in the window, and click

Delete

.

In the Access Restriction area, set the management access level for a user. You must first enable management authorization using the

Perform authorization for exec shell access

option on the

Configuration > Device Management > Users/AAA > AAA Access > Authorization tab.


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31-19



Step 8

Step 9

•

•

Full Access (ASDM, Telnet, SSH and console)

—If you configure authentication for management access using the local database (see the

“Configuring Authentication for CLI, ASDM, and enable command Access” section on page 32-11

), then this option lets the user use ASDM, SSH, Telnet, and the console port. If you also enable authentication, then the user can access global configuration mode.

– Privilege Level

—Selects the privilege level for this user to use with local command authorization. The range is 0 (lowest) to 15 (highest) See the

“Configuring Command

Authorization” section on page 32-13 for more information.

CLI login prompt for SSH, Telnet and console (no ASDM access)


“Configuring Authentication for CLI, ASDM, and enable command Access” section on page 32-11 ), then this option lets the user

use SSH, Telnet, and the console port. The user cannot use ASDM for configuration (if you configure HTTP authentication). ASDM monitoring is allowed. If you also configure enable authentication, then the user cannot access global configuration mode.

• No ASDM, SSH, Telnet, or console access



), then this option disallows the user from accessing any management access method for which you configured authentication (excluding the Serial option; serial access is allowed).

If you want to configure VPN policy attributes for this user, see the “Configuring VPN Policy Attributes for a User” section on page 31-20 .

Click

Apply

.

The user is added to the local adaptive security appliance database, and changes are saved to the running configuration.

Note

To configure the enable password from the User Accounts pane (see the

“Configuring the Hostname,

Domain Name, and Passwords” section on page 9-1

), change the password for the enable_15 user. The enable_15 user is always present in this pane, and represents the default username. This method of configuring the enable password is the only method available in ASDM for the system configuration. If you configured other enable level passwords at the CLI (

enable password 10

, for example), then those users are listed as enable_10, and so on.

Configuring VPN Policy Attributes for a User

By default, each user inherits the settings set in the VPN policy. To override the settings, you can customize VPN attributes by performing the following steps:

Step 1

Step 2

If you have not already added a user according to the “Adding a User Account” section on page 31-18

, from the Configuration > Device Management > Users/AAA > User Accounts pane, click

Add

.

The Add User Account-Identity dialog box appears.

In the left-hand pane, click

VPN Policy

.

31-20


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By default, the Inherit check box is checked for each option, which means the user account inherits the settings from the VPN policy. To override each setting, uncheck the

Inherit

check box, and enter a new value:

a.

b.

Choose a group policy from the list.

Specify which tunneling protocols are available for use, or whether the value is inherited from the group policy. Check the desired

Tunneling Protocols

check boxes to choose the VPN tunneling protocols that are available for use. Only the selected protocols are available for use. The choices are as follows:

–

–

–

–

IPSec provides the most complete architecture for VPN tunnels, and it is perceived as the most secure protocol. Both LAN-to-LAN (peer-to-peer) connections and client-to-LAN connections can use IPSec.

VPN via SSL/TLS (Clientless SSL VPN) uses a web browser to establish a secure remote-access tunnel to a VPN Concentrator; requires neither a software nor hardware client.

Clientless SSL VPN can provide easy access to a broad range of enterprise resources, including corporate websites, web-enabled applications, NT/AD file shares (web-enabled), e-mail, and other TCP-based applications from almost any computer that can reach HTTPS Internet sites.

The SSL VPN Client lets users connect after downloading the Cisco AnyConnect Client application. Users use a clientless SSL VPN connection to download this application the first time. Client updates then occur automatically as needed whenever the user connects.

L2TP over IPSec allows remote users with VPN clients provided with several common PC and mobile PC operating systems to establish secure connections over the public IP network to the adaptive security appliance and private corporate networks.

Note

If no protocol is selected, an error message appears.

Step 3 c.

d.

e.

Specify which filter (IPv4 or IPv6) to use, or whether to inherit the value from the group policy.

Filters consist of rules that determine whether to allow or reject tunneled data packets coming through the adaptive security appliance, based on criteria such as source address, destination address, and protocol. To configure filters and rules, see the Configuration > VPN > VPN General

> Group Policy pane.

Click

Manage

to display the ACL Manager pane, on which you can add, edit, and delete ACLs and

ACEs.

Specify whether to inherit the tunnel group lock or to use the selected tunnel group lock, if any.

Selecting a specific lock restricts users to remote access through this group only. Tunnel Group Lock restricts users by checking if the group configured in the VPN client is the same as the user’s assigned group. If it is not, the adaptive security appliance prevents the user from connecting. If the

Inherit check box is not checked, the default value is None.

f.

Specify whether to inherit the Store Password on Client System setting from the group. Uncheck the

Inherit check box to activate the Yes and No radio buttons. Click

Yes

to store the login password on the client system (potentially a less-secure option). Click

No

(the default) to require the user to enter the password with each connection. For maximum security, we recommend that you

not do allow

password storage. This parameter has no effect on interactive hardware client authentication or individual user authentication for a VPN 3002.

To change Connection Settings, uncheck the

Inherit

check box, and enter a new value:

a.

If the Inherit check box is not checked, you can select the name of an existing access hours policy, if any, to apply to this user or create a new access hours policy. The default value is Inherit, or, if the

Inherit check box is not checked, the default value is Unrestricted.

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31-21


Configuring LDAP Attribute Maps b.

c.

Click

New

to open the Add Time Range dialog box, in which you can specify a new set of access hours.

If the Inherit check box is not checked, the Simultaneous Logins parameter specifies the maximum number of simultaneous logins allowed for this user. The default value is 3. The minimum value is

0, which disables login and prevents user access.

Note

While there is no maximum limit, allowing several simultaneous connections could compromise security and affect performance.

Step 4

Step 5

Step 6 d.

e.

If the Inherit check box is not checked, the Maximum Connect Time parameter specifies the maximum user connection time in minutes. At the end of this time, the system terminates the connection. The minimum is 1 minute, and the maximum is 2147483647 minutes (over 4000 years).

To allow unlimited connection time, check the

Unlimited

check box (the default).

If the Inherit check box is not checked, the Idle Timeout parameter specifies this user’s idle timeout period in minutes. If there is no communication activity on the user’s connection in this period, the system terminates the connection. The minimum time is 1 minute, and the maximum time is 10080 minutes. This value does not apply to users of clientless SSL VPN connections.

To set a dedicated IP address for this user, enter an IP address and subnet mask in the Dedicated IP

Address (Optional) area.

To configure clientless SSL settings, in the left-hand pane, click


. To override each setting, uncheck the

Inherit

check box, and enter a new value.

Click

Apply

.


Configuring LDAP Attribute Maps

If you are introducing an adaptive security appliance to an existing LDAP directory, your existing LDAP attribute names and values are probably different from the existing ones. You must create LDAP attribute maps that map your existing user-defined attribute names and values to Cisco attribute names and values that are compatible with the adaptive security appliance. You can then bind these attribute maps to LDAP servers or remove them, as needed. You can also show or clear attribute maps.

Note

To use the attribute mapping features correctly, you need to understand Cisco LDAP attribute names and values, as well as the user-defined attribute names and values.

The names of frequently mapped Cisco LDAP attributes and the type of user-defined attributes that they would commonly be mapped to include the following:

•

•

•

IETF-Radius-Class—A department or user group

IETF-Radius-Filter-Id—An access control list

IETF-Radius-Framed-IP-Address—A static IP address

•

•

IPSec-Banner1—An organization title

Tunneling-Protocols—Allows or denies dial-in

31-22


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Adding an Authentication Prompt

To map the LDAP attribute names used in your organization to their Cisco counterparts on the adaptive security appliance, perform the following steps:

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 1

Step 9

Step 10

Step 11

Step 12

Step 13

Step 14

Step 15

Choose

Configuration > Remote Access VPN > AAA Local Users > LDAP Attribute Map

, and then click

Add

.

The Add LDAP Attribute Map dialog box appears with the Map Name tab active.

In the Name field, add a name for the map.

In the Customer Name field, add the name of your organization’s corresponding attribute.

From the Cisco Name drop-down list, choose an attribute.

Click

Add

.

To add more names, repeat Steps

1 through 5 .

To map the customer names, click the

Map Value

tab.

Click

Add

.

The Add LDAP Attributes Map Value dialog box appears.

Choose the attribute from the Customer Name drop-down list.

In the Customer Value field, add the value for this attribute.

In the Cisco Value field, add the Cisco value to which the value in Step 10 maps.

Click

Add

.

The values are mapped.

To map more names, repeat Steps

8

through

12 .

Click

OK

to return to the Map Value tab, and then click

OK

again to close the dialog box.

In the LDAP Attribute Map pane, click

Apply

.

The value mappings are saved to the running configuration.

Adding an Authentication Prompt

You can specify text to display to the user during the AAA authentication challenge process. You can specify the AAA challenge text for HTTP, FTP, and Telnet access through the adaptive security appliance when requiring user authentication from TACACS+ or RADIUS servers. This text is primarily for cosmetic purposes and appears above the username and password prompts that users see when they log in.

If you do not specify an authentication prompt, users see the following when authenticating with a

RADIUS or TACACS+ server:

Connection Type Default Prompt

FTP FTP authentication

HTTP

Telnet

HTTP Authentication

None

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31-23


AAA Servers Monitoring

To add an authentication prompt, perform the following steps:

Step 1

From the Configuration > Device Management > Users/AAA > Authentication Prompt pane, add a message to appear above the username and password prompts that users see when they log in by entering text in the Prompt field.

The following are the allowed character limits for authentication prompts:

Application

Microsoft Internet Explorer

Telnet

FTP

Character Limit for

Authentication Prompt

37

235

235

Step 2

Step 3

In the Messages area, add messages in the User accepted message and User rejected message fields.

If the user authentication occurs from Telnet, you can use the User accepted message and User rejected message options to display different status prompts to indicate that the authentication attempt is accepted or rejected by the AAA server.

If the AAA server authenticates the user, the adaptive security appliance displays the User accepted message text, if specified, to the user; otherwise, the adaptive security appliance displays the User rejected message text, if specified. Authentication of HTTP and FTP sessions displays only the challenge text at the prompt. The User accepted message and User rejected message text are not displayed.

Click

Apply

.


AAA Servers Monitoring

To monitor AAA Servers, see the following panes:

Path

Monitoring > Properties > AAA Servers

Purpose

Shows the configured AAA server statistics.

Monitoring > Properties > AAA Servers Shows the AAA server running configuration.

Choose


, then press

Send

.

Shows all LDAP attribute maps in the running configuration.

Choose


, then press

Send

.

Shows the Zone Labs Integrity server configuration.

Choose


, then press

Send

.

Applies only to AD servers using LDAP, and shows groups that are listed on an AD server.

31-24


OL-20339-01




For additional information related to implementing LDAP mapping, see the following sections:

•


•

RFCs, page 31-26

OL-20339-01


31-25


Feature History for AAA Servers


Related Topic

LDAP commands and AAA server host mode commands

Example configuration procedures used to set up

LDAP authentication or authorization

Document Title


Configuring an External Server for Authorization and

Authentication, page B-1

List of Cisco LDAP attribute names and values

Extracting data from the HTTP GET and POST exchanges when using HTTP Form (if logging into the authenticating web server directly, instead of through the adaptive security appliance)


RFCs

RFC

2138

2139

2548

2868

Title

Remote Authentication Dial In User Service (RADIUS)

RADIUS Accounting

Microsoft Vendor-specific RADIUS Attributes

RADIUS Attributes for Tunnel Protocol Support

Feature History for AAA Servers

Table 2 lists each feature change and the platform release in which it was implemented. ASDM is


Table 2 Feature History for AAA Servers

Feature Name

AAA Servers

Platform

Releases

7.0(1)


AAA Servers describes support for AAA and how to configure AAA servers and the local database.


Configuration > Device Management > Users/AAA >


Configuration > Remote Access VPN > AAA Local Users

> LDAP Attribute Map

Configuration > Device Management > Users/AAA >

User Accounts

31-26


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C H A P T E R

32


This chapter describes how to access the adaptive security appliance for system management through

Telnet, SSH, and HTTPS (using ASDM). It also describes how to authenticate and authorize users and how to create login banners.


•

•

•

•

•

Configuring Device Access for ASDM, Telnet, or SSH, page 32-1

Configuring CLI Parameters, page 32-3

Configuring File Access, page 32-5

Configuring ICMP Access, page 32-9

•

Configuring a Management Interface for Management on a Different Interface from the VPN Tunnel

Termination Interface, page 32-10

Configuring AAA for System Administrators, page 32-10

Note

To access the adaptive security appliance interface for management access, you do not also need an access rule allowing the host IP address. You only need to configure management access according to the sections in this chapter.

To configure the Management IP address for transparent firewall mode, see the

“Setting the Management

IP Address for a Transparent Firewall” section on page 9-14

.

Configuring Device Access for ASDM, Telnet, or SSH

This section describes how to allow clients to access the device using ASDM, Telnet, or SSH.

•

•

Configuring Management Access, page 32-1

Using an SSH Client, page 32-3


You can manage the adaptive security appliance using ASDM, Telnet, or SSH.

SSH is an application running on top of a reliable transport layer, such as TCP/IP, that provides strong authentication and encryption capabilities.

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32-1

Chapter 32 Configuring Management Access

Configuring Device Access for ASDM, Telnet, or SSH

Restrictions

•

•

You cannot use Telnet to the lowest security interface unless you use Telnet inside an IPSec tunnel.

The adaptive security appliance allows :

–

A maximum of 5 concurrent Telnet connections per context, if available, with a maximum of

100 connections divided between all contexts.

–

–

A maximum of 5 concurrent SSH connections per context, if available, with a maximum of 100 connections divided between all contexts.

A maximum of 5 concurrent ASDM instances per context, if available, with a maximum of 32

ASDM instances between all contexts.

The adaptive security appliance supports the SSH remote shell functionality provided in SSH Versions

1 and 2 and supports DES and 3DES ciphers.

Detailed Steps

Note

XML management over SSL and SSH is not supported.

Step 1

Step 2

Step 3

Step 4

Choose the

Configuration > Device Management > Management Access >

ASDM/HTTPS/Telnet/SSH

pane, click

Add

.

The Add Device Access Configuration dialog box appears in the right-hand pane.

Choose the type of session from the three options listed:

ASDM/HTTPS

,

Telnet

, or

SSH

.

From the Interface Name drop-down list, choose the interface to use for administrative access.

In the IP Address field, add the IP address of the network or host that is allowed access. The field allows

IPv6 addresses.

Note

When you enter a colon (:) in the IP Address field for an IPv6 address, the Netmask field changes to Prefix Length.

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

From the Mask drop-down list, choose the mask associated with the network or host that is allowed access.

For ASDM/HTTPS sessions, verify that the Enable HTTP Server check box is checked. This is the default setting.

Specify the port number. The default port is 443.

Adjust the Idle Timeout or Session Timeout if necessary. There is no timeout value by default. This setting is available only in single, routed mode.

For Telnet sessions, the default timeout value is 5 minutes. To change this value, type a new one in the

Telnet Timeout field.

For SSH sessions, the default timeout value is 5 minutes. To change this value, type a new one in the

SSH Timeout field.

Click

Apply

.


32-2


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Configuring CLI Parameters

Using an SSH Client

To gain access to the adaptive security appliance console using SSH, at the SSH client enter the username

asa

and enter the login password set by the

password

command (see the

“Configuring the Hostname,

Domain Name, and Passwords” section on page 9-1

).

When starting an SSH session, a dot (.) displays on the adaptive security appliance console before the

SSH user authentication prompt appears, as follows: hostname(config)# .

The display of the dot does not affect the functionality of SSH. The dot appears at the console when generating a server key or decrypting a message using private keys during SSH key exchange before user authentication occurs. These tasks can take up to two minutes or longer. The dot is a progress indicator that verifies that the adaptive security appliance is busy and has not hung.



•

Configuring a Login Banner, page 32-3

•

•

Customizing a CLI Prompt, page 32-4

Changing the Console Timeout Period, page 32-5

Configuring a Login Banner

You can configure a message to display when a user connects to the adaptive security appliance, before a user logs in, or before a user enters privileged EXEC mode.

Restrictions

After a banner is added, Telnet or SSH sessions to adaptive security appliance may close if:

•

There is not enough system memory available to process the banner message(s).

•

A TCP write error occurs when attempting to display banner message(s).

Guidelines

•

From a security perspective, it is important that your banner discourage unauthorized access. Do not use the words “welcome” or “please,” as they appear to invite intruders in. The following banner sets the correct tone for unauthorized access:

You have logged in to a secure device. If you are not authorized to access this device, log out immediately or risk possible criminal consequences.

•

See RFC 2196 for guidelines about banner messages.

Detailed Steps

Step 1

Choose the

Configuration > Device Management > Management Access > Command Line (CLI) >

Banner

pane, add your banner text to the field for the type of banner you are creating for the CLI:


OL-20339-01 32-3



Step 2

•

•

•

•

Session (exec) banner—This banner appears when a user accesses privileged EXEC mode at the

CLI.

Login Banner—This banner appears when a user logs in to the CLI.

Message-of-the-day (motd) Banner—This banner appears when a user first connects to the CLI.

ASDM Banner—This banner appears when a user connects to ASDM, following user authentication. The user is given two options for dismissing the banner:

–

Continue—Dismiss the banner and complete login as usual.

–

Disconnect— Dismiss the banner and terminate the connection.

Only ASCII characters are allowed, including new line (Enter), which counts as two characters.

Do not use tabs in the banner, because they are not preserved in the CLI version.

There is no length limit for banners other than those for RAM and flash memory.

You can dynamically add the hostname or domain name of the adaptive security appliance by including the strings $(hostname) and $(domain).

If you configure a banner in the system configuration, you can use that banner text within a context by using the $(system) string in the context configuration.

Click

Apply

.

Customizing a CLI Prompt

The CLI Prompt pane lets you customize the prompt used during CLI sessions. By default, the prompt shows the hostname of the adaptive security appliance. In multiple context mode, the prompt also displays the context name. You can display the following items in the CLI prompt.

context domain hostname priority state

(Multiple mode only) Displays the name of the current context.

Displays the domain name.

Displays the hostname.

Displays the failover priority as pri (primary) or sec (secondary).

Displays the traffic-passing state of the unit. The following values are displayed for the state:

•

act—Failover is enabled, and the unit is actively passing traffic.

•

•

•

stby— Failover is enabled, and the unit is not passing traffic and is in a standby, failed, or other non-active state.

actNoFailover—Failover is not enabled, and the unit is actively passing traffic.

stbyNoFailover—Failover is not enabled, and the unit is not passing traffic. This might happen when there is an interface failure above the threshold on the standby unit.

Detailed Steps

32-4


OL-20339-01


Configuring File Access

Step 1

Step 2

Choose the

Configuration > Device Management > Management Access > CLI Prompt

pane, do any of the following to customize the prompt:

•

•

To add an attribute to the prompt, click the attribute in the Available Prompts list and then click

Add

.

You can add multiple attributes to the prompt. The attribute is moved from the Available Prompts list to the Selected Prompts list.

To remove an attribute from the prompt, click the attribute in the Selected Prompts list and then click

Delete

. The attribute is moved from the Selected Prompts list to the Available Prompts list.

•

To change the order in which the attributes appear in the command prompt, click the attribute in the

Selected Prompts list and click

Move Up

or

Move Down

to change the order.

The prompt is changed and displays in the CLI Prompt Preview field.

Click

Apply

.

The new prompt is saved to the running configuration.

Changing the Console Timeout Period

To change the console timeout period, or the duration of time the management console remains active before automatically shutting down, perform the following steps.

Detailed Steps

Step 1

Step 2

Choose the

Configuration > Device Management > Management Access > Command Line (CLI) >

Console Timeout

pane, add a new timeout value in minutes.

To specify unlimited, enter 0. The default value is 0.

Click

Apply

.


This section includes the following topics.

•

•

Configuring the FTP Client Mode, page 32-6

Configuring the Adaptive Security Appliance as a Secure Copy Server, page 32-6

•

•

Configuring the Adaptive Security Appliance as a TFTP Client, page 32-6

Adding Mount Points, page 32-7

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32-5



Configuring the FTP Client Mode

The adaptive security appliance can use FTP to upload or download image files or configuration files to or from an FTP server. In passive FTP, the client initiates both the control connection and the data connection. The server, which is the recipient of the data connection in passive mode, responds with the port number to which it is listening for the specific connection.

To configure the FTP client to be in passive mode, perform the following steps:

Step 1

Step 2

From the Configuration > Device Management > Management Access > File Access > FTP Client pane, check

Specify FTP mode as passive

.

Click

Apply

.

The FTP client configuration is changed and the change is saved to the running configuration.

Configuring the Adaptive Security Appliance as a Secure Copy Server

You can enable the secure copy server on the adaptive security appliance. Only clients that are allowed to access the adaptive security appliance using SSH can establish a secure copy connection.

This implementation of the secure copy server has the following limitations:

•

•

The server can accept and terminate connections for secure copy, but cannot initiate them.

The server does not have directory support. The lack of directory support limits remote client access to the adaptive security appliance internal files.

•

•

The server does not support banners.

The server does not support wildcards.

•

The adaptive security appliance license must have the VPN-3DES-AES feature to support SSH version 2 connections.

To configure the adaptive security appliance as a Secure Copy (SCP) server, perform the following steps:

Step 1

Step 2

From the Configuration > Device Management > Management Access > File Access >

Secure Copy

(SCP) Server

pane, check

Enable secure copy server

.

Click

Apply

.

The changes are saved to the running configuration. The adaptive security appliance can function as an

SCP server for transferring files from/to the device.

Configuring the Adaptive Security Appliance as a TFTP Client

TFTP is a simple client/server file transfer protocol described in RFC783 and RFC1350 Rev. 2. You can configure the adaptive security appliance as a TFTP

client

so that it can transfer a copy of its running configuration file to a TFTP

server

using File > Save Running Configuration to TFTP Client or Tools >

Command Line Interface. In this way, you can back up and propagate configuration files to multiple adaptive security appliances.

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The adaptive security appliance supports only one TFTP client. The full path to the TFTP client is specified in Configuration > Device Management > Management Access > File Access > TFTP Client.

Once configured here, you can use a colon (:) to specify the IP address in the CLI

configure net

and

copy

commands. However, any other authentication or configuration of intermediate devices necessary for communication from the adaptive security appliance to the TFTP client is done apart from this function.

To configure the adaptive security appliance as a TFTP client for saving configuration files to a TFTP server, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

From the Configuration > Device Management > Management Access > File Access > TFTP Client pane, check

Enable

.

From the Interface Name drop-down list, choose the interface to use as a TFTP client.

In the IP Address field, add the IP address of the TFTP server where configuration files will be saved.

In the Path field, add the path to the TFTP server where configuration files will be saved.

For example:

/

tftpboot

/

asa

/

config3

Click

Apply

.

The changes are saved to the running configuration. This TFTP server will be used to save the adaptive security appliance configuration files. For more information, see the

“Saving the Running Configuration to a TFTP Server” section on page 75-6 .

Adding Mount Points

Common Internet File System (CIFS) and File Transfer Protocol (FTP) mount points


•

Adding a CIFS Mount Point, page 32-7

•

•

Adding a CIFS Mount Point, page 32-7

Adding an FTP Mount Point, page 32-8

Adding a CIFS Mount Point

To define a CIFS mount point, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

From the Configuration > Device Management > Management Access > File Access > Mount-Points pane, click

Add > CIFS Mount Point

.

The Add CIFS Mount Point dialog box appears.

Check

Enable mount point.

This option attaches the CIFS file system on the adaptive security appliance to the UNIX file tree.

In the Mount Point Name field, add the name of an existing CIFS location.

In the Server Name or IP Address field, add the name or IP address of the server where the mount point is located.

In the Share Name field, add the name of the folder on the CIFS server.

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32-7



Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

In the NT Domain Name field, add the name of the NT Domain where the server resides.

In the User Name field, add the name of the user authorized for file system mounting on the server.

In the Password field, add the password for the user authorized for file system mounting on the server.


Click

OK

.

The Add CIFS Mount Point dialog box closes.

Click

Apply

.

The mount point is added to the adaptive security appliance and the change is saved to the running configuration.

Adding an FTP Mount Point

Note

For an FTP mount point, the FTP Server must have a UNIX directory listing style. Microsoft FTP servers have a default of MS-DOS directory listing style.

To define an FTP mount point, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

From the Configuration > Device Management > Management Access > File Access > Mount-Points pane, click

Add > FTP Mount Point

.

The Add FTP Mount Point dialog box appears.

Check the

Enable

check box.

This option attaches the FTP file system on the adaptive security appliance to the UNIX file tree.

In the Mount Point Name field, add the name of an existing FTP location.

In the Server Name or IP Address field, add the name or IP address of the server where the mount point is located.

In the Mode field, click the radio button for the FTP mode (Active or Passive). When you choose Passive mode, the client initiates both the FTP control connection and data connection. The server responds with the number of its listening port for this connection.

In the Path to Mount field, add the directory path name to the FTP file server.

In the User Name field, add the name of the user authorized for file system mounting on the server.

In the Password field, add the password for the user authorized for file system mounting on the server.


Click

OK

.

The dialog box closes.

Click

Apply

.

The mount point is added to the adaptive security appliance and the change is saved to the running configuration.

32-8


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Configuring ICMP Access

Configuring ICMP Access

By default, you can send ICMP packets to any adaptive security appliance interface using either IPv4 or

IPv6. ICMP in IPv6 functions the same as ICMP in IPv4. ICMPv6 generates error messages, such as

ICMP destination unreachable messages and informational messages like ICMP echo request and reply messages. Additionally ICMP packets in IPv6 are used in the IPv6 neighbor discovery process and path

MTU discovery.

By default, the adaptive security appliance does not respond to ICMP echo requests directed to a broadcast address. You can protect the adaptive security appliance from attacks by limiting the addresses of hosts and networks that are allowed to have ICMP access to the adaptive security appliance.

The adaptive security appliance only responds to ICMP traffic sent to the interface that traffic comes in on; you cannot send ICMP traffic through an interface to a far interface.

Detailed Steps

Note

For allowing ICMP traffic

through

the adaptive security appliance, see

Chapter 30, “Configuring Access

Rules.”

We recommend you always grant permission for the ICMP unreachable message type (type 3). Denying

ICMP unreachable messages disables ICMP Path MTU discovery, which can halt IPSec and PPTP traffic. See RFC 1195 and RFC 1435 for details about Path MTU Discovery.

If you configure ICMP rules, then the adaptive security appliance uses a first match to the ICMP traffic followed by an implicit deny all. That is, if the first matched entry is a permit entry, the ICMP packet continues to be processed. If the first matched entry is a deny entry or an entry is not matched, the adaptive security appliance discards the ICMP packet and generates a syslog message. An exception is when an ICMP rule is not configured; in that case, a permit statement is assumed.

To configure ICMP access rules, perform the following steps.

OL-20339-01

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Choose the

Configuration > Device Management > Management Access > ICMP

pane, click

Add

.

Choose which version of IP to filter by clicking the appropriate radio button:

•

Both

(filters IPv4 and IPv6 traffic)

•

•

IPv4

only

IPv6

only

If you want to insert a rule into the ICMP table, click the rule that the new rule will precede, and click

Insert

.

The Create ICMP Rule dialog box appears in the right-hand pane.

From the ICMP Type drop-down list, choose the type of ICMP message for this rule.

From the Interface list, choose the destination adaptive security appliance interface the rule is to be applied to.

In the IP Address field, do one of the following:

•

Add a specific IP address for the host or network.

•

Click

Any Address

and go to

Step 9

.

From the Mask drop-down list, choose the network mask.


32-9


Configuring a Management Interface for Management on a Different Interface from the VPN Tunnel Termination

Step 8

Step 9

Step 10

Click

OK

.

The dialog box closes.

(Optional) To set ICMP unreachable message limits, set the following options. Increasing the rate limit, along with enabling the “Decrement time to live for a connection” option on the Configuration > Firewall

> Service Policy Rules > Rule Actions > Connection Settings dialog box, is required to allow a traceroute through the adaptive security appliance that shows the adaptive security appliance as one of the hops.

•

•

Rate Limit—Sets the rate limit of unreachable messages, between 1 and 100 messages per second.

The default is 1 message per second.

Burst Size—Sets the burst rate, between 1 and 10. This keyword is not currently used by the system, so you can choose any value.

Click

Apply

.

Configuring a Management Interface for Management on a

Different Interface from the VPN Tunnel Termination Interface

If your IPSec VPN tunnel terminates on one interface, but you want to manage the adaptive security appliance by accessing a different interface, you can identify that interface as a management-access interface. For example, if you enter the adaptive security appliance from the outside interface, this feature lets you connect to the inside interface using Telnet; or you can ping the inside interface when entering from the outside interface.

Restrictions

You can define only one management-access interface.

Detailed Steps

Step 1

Step 2

From the Configuration > Device Management > Management Access > Management Interface pane, choose the interface with the highest security (the inside interface) from the Management Access Interface drop-down list.

Click

Apply

.

The management interface is assigned and the change is saved to the running configuration.

Configuring AAA for System Administrators

This section describes how to enable authentication and command authorization for system administrators. Before you configure AAA for system administrators, first configure the local database or AAA server according to

Chapter 31, “AAA Server and Local Database Support.”


•

Configuring Authentication for CLI, ASDM, and enable command Access, page 32-11


32-10 OL-20339-01



•

•

•

•

•

Limiting User CLI and ASDM Access with Management Authorization, page 32-12

Configuring Command Authorization, page 32-13

Configuring Management Access Accounting, page 32-22

Viewing the Current Logged-In User, page 32-23

Recovering from a Lockout, page 32-24

Configuring Authentication for CLI, ASDM, and enable command Access

If you enable CLI authentication, the adaptive security appliance prompts you for your username and password to log in. After you enter your information, you have access to user EXEC mode.

To enter privileged EXEC mode, enter the

enable

command or the

login

command (if you are using the local database only).

If you configure

enable

authentication, the adaptive security appliance prompts you for your username and password. If you do not configure

enable

authentication, enter the system enable password when you enter the

enable

command (set by the

enable password

command). However, if you do not use

enable

authentication, after you enter the

enable

command, you are no longer logged in as a particular user. To maintain your username, use

enable

authentication.

For authentication using the local database, you can use the

login

command, which maintains the username but requires no configuration to turn on authentication.

Note

Before the adaptive security appliance can authenticate a Telnet, SSH, or HTTP user, you must first configure access to the adaptive security appliance. See the

“Configuring Device Access for ASDM,

Telnet, or SSH” section on page 32-1

. This configuration identifies the IP addresses that are allowed to communicate with the adaptive security appliance.

Detailed Steps

To configure CLI, ASDM, or

enable

authentication, perform the following steps:

Step 1

Step 2

To authenticate users who use the

enable

command, go to Configuration > Device Management >

Users/AAA > AAA Access > Authentication, and configure the following settings:

a.

b.

Check the

Enable

check box.

From the Server Group drop-down list, choose a server group name or the LOCAL database.

c.

(Optional) If you chose a AAA server, you can configure the adaptive security appliance to use the local database as a fallback method if the AAA server is unavailable. Click the

Use LOCAL when server group fails

check box. We recommend that you use the same username and password in the local database as the AAA server because the adaptive security appliance prompt does not give any indication which method is being used.

To authenticate users who access the CLI or ASDM, go to Configuration > Device Management >

Users/AAA > AAA Access > Authentication, and configure the following settings:

a.

•

Check one or more of the following check boxes:

HTTP/ASDM

—Authenticates the ASDM client that accesses the adaptive security appliance using

HTTPS. You only need to configure HTTP authentication if you want to use a AAA server. By default, ASDM uses the local database for authentication even if you do not configure this command.


OL-20339-01 32-11



Step 3

•

•

Serial

—Authenticates users who access the adaptive security appliance using the console port.

SSH

—Authenticates users who access the adaptive security appliance using SSH.

Telnet

—Authenticates users who access the adaptive security appliance using Telnet.

• b.

c.

For each service that you checked, from the Server Group drop-down list, choose a server group name or the LOCAL database.

(Optional) If you chose a AAA server, you can configure the adaptive security appliance to use the local database as a fallback method if the AAA server is unavailable. Click the


check box. We recommend that you use the same username and password in the local database as the AAA server because the adaptive security appliance prompt does not give any indication which method is being used.

Click

Apply

.

Detailed Steps

Limiting User CLI and ASDM Access with Management Authorization

If you configure CLI or

enable

authentication, you can limit a local user, RADIUS, TACACS+, or LDAP user (if you map LDAP attributes to RADIUS attributes) from accessing the CLI, ASDM, or the

enable

command.

Detailed Steps

Note

Serial access is not included in management authorization, so if you enable the Authentication > Serial option, then any user who authenticates can access the console port.

To configure management authorization, perform the following steps:

Step 1

Step 2

To enable management authorization, go to Configuration > Device Management > Users/AAA > AAA

Access > Authorization, and check the

Perform authorization for exec shell access > Enable

check box.

This option also enables support of administrative user privilege levels from RADIUS, which can be used in conjunction with local command privilege levels for command authorization. See the

“Configuring Local Command Authorization” section on page 32-15


To configure the user for management authorization, see the following requirements for each AAA server type or local user:

•

•

RADIUS or LDAP (mapped) users—Configure the Service-Type attribute for one of the following values.

RADIUS or LDAP (mapped) users—Use the IETF RADIUS numeric Service-Type attribute which maps to one of the following values.

–

Service-Type 6 (Administrative)—Allows full access to any services specified by the

Authentication tab options

32-12


OL-20339-01



•

•

–

–

Service-Type 5 (Outbound)—Denies management access. The user cannot use any services specified by the Authentication tab options (excluding the Serial option; serial access is allowed). Remote-access (IPSec and SSL) users can still authenticate and terminate their remote-access sessions.

TACACS+ users—Authorization is requested with the “service=shell” and the server responds with

PASS or FAIL.

–

Service-Type 7 (NAS prompt)—Allows access to the CLI when you configure the Telnet or SSH authentication options, but denies ASDM configuration access if you configure the HTTP option. ASDM monitoring access is allowed. If you configure

enable

authentication with the

Enable option, the user cannot access privileged EXEC mode using the

enable

command.

–

PASS, privilege level 1—Allows full access to any services specified by the Authentication tab options.

PASS, privilege level 2 and higher—Allows access to the CLI when you configure the Telnet or

SSH authentication options, but denies ASDM configuration access if you configure the HTTP option. ASDM monitoring access is allowed. If you configure

enable

authentication with the

Enable option, the user cannot access privileged EXEC mode using the

enable

command.

–

FAIL—Denies management access. The user cannot use any services specified by the

Authentication tab options (excluding the Serial option; serial access is allowed).

Local users—Configure the Access Restriction option. See the

“Adding a User Account” section on page 31-18

. By default, the access restriction is Full Access, which allows full access to any services specified by the Authentication tab options.

Configuring Command Authorization

If you want to control the access to commands, the adaptive security appliance lets you configure command authorization, where you can determine which commands that are available to a user. By default when you log in, you can access user EXEC mode, which offers only minimal commands. When you enter the

enable

command (or the

login

command when you use the local database), you can access privileged EXEC mode and advanced commands, including configuration commands.


•

•

•

Command Authorization Overview, page 32-13

Configuring Local Command Authorization, page 32-15

Configuring TACACS+ Command Authorization, page 32-18

Command Authorization Overview

•

•

•

This section describes command authorization and includes the following topics:

Supported Command Authorization Methods, page 32-14

About Preserving User Credentials, page 32-14

Security Contexts and Command Authorization, page 32-15

OL-20339-01


32-13



Supported Command Authorization Methods

You can use one of two command authorization methods:

•

Local privilege levels—Configure the command privilege levels on the adaptive security appliance.

When a local, RADIUS, or LDAP (if you map LDAP attributes to RADIUS attributes) user authenticates for CLI access, the adaptive security appliance places that user in the privilege level that is defined by the local database, RADIUS, or LDAP server. The user can access commands at the user’s privilege level and below. Note that all users access user EXEC mode when they first log in (commands at level 0 or 1). The user needs to authenticate again with the

enable

command to access privileged EXEC mode (commands at level 2 or higher), or they can log in with the

login

command (local database only).

Note

You can use local command authorization without any users in the local database and without

CLI or

enable

authentication. Instead, when you enter the

enable

command, you enter the system enable password, and the adaptive security appliance places you in level 15. You can then create enable passwords for every level, so that when you enter

enable

n

(2 to 15), the adaptive security appliance places you in level

n

. These levels are not used unless you turn on local command authorization (see

“Configuring Local Command Authorization”

). (See the

Cisco ASA

5500 Series Command Reference

for more information about the

enable

command.)

•

TACACS+ server privilege levels—On the TACACS+ server, configure the commands that a user or group can use after they authenticate for CLI access. Every command that a user enters at the CLI is checked with the TACACS+ server.

About Preserving User Credentials

When a user logs into the adaptive security appliance, they are required to provide a username and password for authentication. The adaptive security appliance retains these session credentials in case further authentication is needed later in the session.

When the following configurations are in place, a user needs only to authenticate with the local server upon login. Subsequent serial authorization uses the saved credentials. The user is also prompted for the privilege level 15 password. When exiting privileged mode, the user is authenticated again. User credentials are not retained in privileged mode.

•

•

Local server is configured to authenticate user access.

Privilege level 15 command access is configured to require a password.

User’s account is configured for serial only authorization (no access to console or ASDM).

•

•

User’s account is configured for privilege level 15 command access.

The following table shows how credentials are used in this case by the adaptive security appliance.

Credentials required

Username

Password

Privileged Mode

Password

Username and

Password

Authentication

Yes

Yes

No

Serial

Authorization

No

No

No

Privileged Mode

Command

Authorization

Privileged

Mode Exit

Authorization

No

No

Yes

Yes

Yes

No

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OL-20339-01



Security Contexts and Command Authorization

The following are important points to consider when implementing command authorization with multiple security contexts:

•

AAA settings are discrete per context, not shared between contexts.

When configuring command authorization, you must configure each security context separately.

This provides you the opportunity to enforce different command authorizations for different security contexts.

•

When switching between security contexts, administrators should be aware that the commands permitted for the username specified when they login may be different in the new context session or that command authorization may not be configured at all in the new context. Failure to understand that command authorizations may differ between security contexts could confuse an administrator.

This behavior is further complicated by the next point.

New context sessions started with the

changeto

command always use the default “enable_15” username as the administrator identity, regardless of what username was used in the previous context session. This behavior can lead to confusion if command authorization is not configured for the enable_15 user or if authorizations are different for the enable_15 user than for the user in the previous context session.

This behavior also affects command accounting, which is useful only if you can accurately associate each command that is issued with a particular administrator. Because all administrators with permission to use the

changeto

command can use the enable_15 username in other contexts, command accounting records may not readily identify who was logged in as the enable_15 username. If you use different accounting servers for each context, tracking who was using the enable_15 username requires correlating the data from several servers.

When configuring command authorization, consider the following:

–

–

An administrator with permission to use the

changeto

command effectively has permission to use all commands permitted to the enable_15 user in each of the other contexts.

If you intend to authorize commands differently per context, ensure that in each context the enable_15 username is denied use of commands that are also denied to administrators who are permitted use of the

changeto

command.

When switching between security contexts, administrators can exit privileged EXEC mode and enter the

enable

command again to use the username they need.

Note

The system execution space does not support AAA commands; therefore, command authorization is not available in the system execution space.

Configuring Local Command Authorization

Local command authorization lets you assign commands to one of 16 privilege levels (0 to 15). By default, each command is assigned either to privilege level 0 or 15. You can define each user to be at a specific privilege level, and each user can enter any command at their privilege level or below. The adaptive security appliance supports user privilege levels defined in the local database, a RADIUS server, or an LDAP server (if you map LDAP attributes to RADIUS attributes. See the

“Configuring

LDAP Attribute Maps” section on page 31-22

.)


•

Local Command Authorization Prerequisites, page 32-16

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32-15



•

•

•

Default Command Privilege Levels, page 32-16

Assigning Privilege Levels to Commands and Enabling Authorization, page 32-17

Viewing Command Privilege Levels, page 32-18

Local Command Authorization Prerequisites

Complete the following tasks as part of your command authorization configuration:

•

Configure

enable

authentication. (See the


.)

enable

authentication is essential to maintain the username after the user accesses the

enable

command.

Alternatively, you can use the

login

command (which is the same as the

enable

command with authentication; for the local database only), which requires no configuration. We do not recommend this option because it is not as secure as

enable

authentication.

You can also use CLI authentication, but it is not required.

•

See the following prerequisites for each user type:

–

Local database users—Configure each user in the local database at a privilege level from 0 to 15.

–

To configure the local database, see the


.

RADIUS users—Configure the user with Cisco VSA CVPN3000-Privilege-Level with a value between 0 and 15.

–

LDAP users—Configure the user with a privilege level between 0 and 15, and then map the

LDAP attribute to Cisco VAS CVPN3000-Privilege-Level according to the

“Configuring LDAP

Attribute Maps” section on page 31-22 .

Default Command Privilege Levels

By default, the following commands are assigned to privilege level 0. All other commands are at level 15.

•

•

•

•

•

•

•

•

•

•

•

• show checksum show curpriv enable help show history login logout pager show pager clear pager quit show version

If you move any configure mode commands to a lower level than 15, be sure to move the

configure

command to that level as well, otherwise, the user will not be able to enter configuration mode.

To view all privilege levels, see the “Viewing Command Privilege Levels” section on page 32-18

.


32-16 OL-20339-01



Assigning Privilege Levels to Commands and Enabling Authorization

This section assigns a command to a new privilege level, and enables authorization.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

To enable command authorization, go to Configuration > Device Management > Users/AAA > AAA

Access > Authorization, and check

Enable authorization for command access > Enable

.

From the Server Group drop-down list, choose

LOCAL

.

When you enable local command authorization, you have the option of manually assigning privilege levels to individual commands or groups of commands or enabling the predefined user account privileges.

•

To use predefined user account privileges, click

Set ASDM Defined User Roles

.

The ASDM Defined User Roles Setup dialog box shows the commands and their levels. Click

Yes

to use the predefined user account privileges: Admin (privilege level 15, with full access to all CLI commands; Read Only (privilege level 5, with read-only access); and Monitor Only (privilege level

3, with access to the Monitoring section only).

•

To manually configure command levels, click

Configure Command Privileges

.

The Command Privileges Setup dialog box appears. You can view all commands by choosing

--All

Modes--

from the Command Mode drop-down list, or you can choose a configuration mode to view the commands available in that mode. For example, if you choose

context

, you can view all commands available in context configuration mode. If a command can be entered in user

EXEC/privileged EXEC mode as well as configuration mode, and the command performs different actions in each mode, you can set the privilege level for these modes separately.

The Variant column displays show, clear, or cmd. You can set the privilege only for the show, clear, or configure form of the command. The configure form of the command is typically the form that causes a configuration change, either as the unmodified command (without the

show

or

clear

prefix) or as the

no

form.

To change the level of a command, double-click it or click

Edit

. You can set the level between 0 and

15. You can only configure the privilege level of the

main

command. For example, you can configure the level of all

aaa

commands, but not the level of the

aaa authentication

command and the

aaa authorization

command separately.

To change the level of all shown commands, click

Select All

and then

Edit

.

Click

OK

to accept your changes.

To support administrative user privilege levels from RADIUS, check

Perform authorization for exec shell access > Enable

.

Without this option, the adaptive security appliance only supports privilege levels for local database users and defaults all other types of users to level 15.

This option also enables management authorization for local, RADIUS, LDAP (mapped), and TACACS+ users. See the

“Limiting User CLI and ASDM Access with Management Authorization” section on page 32-12


Click

Apply

.

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32-17



Viewing Command Privilege Levels

The following commands when used in Tools > Command Line Interface let you view privilege levels for commands.

Command show running-config all privilege all show running-config privilege level

level

show running-config privilege command

command

Purpose

Shows all commands.

Shows commands for a specific level. The

level

is an integer between 0 and 15.

Shows the level of a specific command.

Examples

For example, for the

show running-config all privilege all

command, the system displays the current assignment of each CLI command to a privilege level. The following is sample output from the command.

Enter the following command in the Tools > Command Line Interface tool:

show running-config all privilege all

privilege show level 15 command aaa privilege clear level 15 command aaa privilege configure level 15 command aaa privilege show level 15 command aaa-server privilege clear level 15 command aaa-server privilege configure level 15 command aaa-server privilege show level 15 command access-group privilege clear level 15 command access-group privilege configure level 15 command access-group privilege show level 15 command access-list privilege clear level 15 command access-list privilege configure level 15 command access-list privilege show level 15 command activation-key privilege configure level 15 command activation-key

....

The following command displays the command assignments for privilege level 10:

show running-config privilege level 10

privilege show level 10 command aaa

The following command displays the command assignment for the

access-list

command:

show running-config privilege command access-list

privilege show level 15 command access-list privilege clear level 15 command access-list privilege configure level 15 command access-list

Configuring TACACS+ Command Authorization

If you enable TACACS+ command authorization, and a user enters a command at the CLI, the adaptive security appliance sends the command and username to the TACACS+ server to determine if the command is authorized.

32-18


OL-20339-01



When configuring command authorization with a TACACS+ server, do not save your configuration until you are sure it works the way you want. If you get locked out because of a mistake, you can usually recover access by restarting the adaptive security appliance. If you still get locked out, see the

“Recovering from a Lockout” section on page 32-24

.

Be sure that your TACACS+ system is completely stable and reliable. The necessary level of reliability typically requires that you have a fully redundant TACACS+ server system and fully redundant connectivity to the adaptive security appliance. For example, in your TACACS+ server pool, include one server connected to interface 1, and another to interface 2. You can also configure local command authorization as a fallback method if the TACACS+ server is unavailable. In this case, you need to configure local users and command privilege levels according to the

“Configuring Command

Authorization” section on page 32-13

.


•

•

•

TACACS+ Command Authorization Prerequisites, page 32-19

Configuring Commands on the TACACS+ Server, page 32-19

Enabling TACACS+ Command Authorization, page 32-22

TACACS+ Command Authorization Prerequisites

Complete the following tasks as part of your command authorization configuration:

•

Configure CLI and

enable

authentication (see the


).

Configuring Commands on the TACACS+ Server

You can configure commands on a Cisco Secure Access Control Server (ACS) TACACS+ server as a shared profile component, for a group, or for individual users. For third-party TACACS+ servers, see your server documentation for more information about command authorization support.

See the following guidelines for configuring commands in Cisco Secure ACS Version 3.1; many of these guidelines also apply to third-party servers:

•

The adaptive security appliance sends the commands to be authorized as “shell” commands, so configure the commands on the TACACS+ server as shell commands.

Note

Cisco Secure ACS might include a command type called “pix-shell.” Do not use this type for adaptive security appliance command authorization.

•

•

The first word of the command is considered to be the main command. All additional words are considered to be arguments, which need to be preceded by

permit

or

deny

.

For example, to allow the

show running-configuration aaa-server

command, add

show running-configuration

to the command field, and type

permit aaa-server

in the arguments field.

You can permit all arguments of a command that you do not explicitly deny by checking the

Permit

Unmatched Args

check box.

For example, you can configure just the

show

command, and then all the

show

commands are allowed. We recommend using this method so that you do not have to anticipate every variant of a command, including abbreviations and

?

, which shows CLI usage (see

Figure 32-1

).

OL-20339-01


32-19


Figure 32-1 Permitting All Related Commands


•

For commands that are a single word, you

must

permit unmatched arguments, even if there are no arguments for the command, for example

enable

or

help

(see

Figure 32-2 ).

Figure 32-2 Permitting Single Word Commands

•

To disallow some arguments, enter the arguments preceded by

deny

.

For example, to allow

enable

, but not

enable password

, enter

enable

in the commands field, and

deny password

in the arguments field. Be sure to check the

Permit Unmatched Args

check box so that

enable

alone is still allowed (see

Figure 32-3 ).

32-20


OL-20339-01


Figure 32-3 Disallowing Arguments


•

When you abbreviate a command at the command line, the adaptive security appliance expands the prefix and main command to the full text, but it sends additional arguments to the TACACS+ server as you enter them.

For example, if you enter

sh log

, then the adaptive security appliance sends the entire command to the TACACS+ server,

show logging

. However, if you enter

sh log mess

, then the adaptive security appliance sends

show logging mess

to the TACACS+ server, and not the expanded command

show logging message

. You can configure multiple spellings of the same argument to anticipate abbreviations (see

Figure 32-4

).

Figure 32-4 Specifying Abbreviations

OL-20339-01

•

We recommend that you allow the following basic commands for all users:

–

– show checksum show curpriv

–

–

–

–

–

– enable help show history login logout pager


32-21



Enabling TACACS+ Command Authorization

Before you enable TACACS+ command authorization, be sure that you are logged into the adaptive security appliance as a user that is defined on the TACACS+ server, and that you have the necessary command authorization to continue configuring the adaptive security appliance. For example, you should log in as an admin user with all commands authorized. Otherwise, you could become unintentionally locked out.

Detailed Steps

– show pager

–

– clear pager quit

– show version

Step 1

Step 2

Step 3

Step 4

To perform command authorization using a TACACS+ server, go to Configuration > Device

Management > Users/AAA > AAA Access > Authorization, and check the

Enable authorization for command access > Enable

check box.

From the Server Group drop-down list, choose a AAA server group name.

(Optional) you can configure the adaptive security appliance to use the local database as a fallback method if the AAA server is unavailable. Click the


check box.

We recommend that you use the same username and password in the local database as the AAA server because the adaptive security appliance prompt does not give any indication which method is being used.

Be sure to configure users in the local database (see the


) and command privilege levels (see the


).

Click

Apply

.

Configuring Management Access Accounting

You can configure accounting when users log in, when they enter the

enable

command, or when they issue commands.

Prerequisites

You can only account for users that first authenticate with the adaptive security appliance, so configure authentication using the

“Configuring Authentication for CLI, ASDM, and enable command Access” section on page 32-11 .

For information about configuring a AAA server group, see the

“Configuring AAA Server Groups” section on page 31-8 . For CLI access, you can use TACACS+ or RADIUS servers. For command

accounting, you can only use TACACS+ servers.

Detailed Steps

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Step 1

Step 2

Step 3

Step 4

To enable accounting of users when they enter the

enable

command:

a.

b.

Go to Configuration > Device Management > Users/AAA > AAA Access > Accounting, and check the

Require accounting to allow accounting of user activity > Enable

check box.

From the Server Group drop-down list, choose a RADIUS or TACACS+ server group name.

To enable accounting of users when they access the adaptive security appliance using Telnet, SSH, or the serial console:

a.

Under the Require accounting for the following types of connections area, check the check boxes for Serial, SSH, and/or Telnet.

b.

For each connection type, from the Server Group drop-down list, choose a RADIUS or TACACS+ server group name.

To configure command accounting:

a.

b.

Under the Require command accounting area, check

Enable

.

From the Server Group drop-down list, choose a TACACS+ server group name. RADIUS is not supported.

c.

You can send accounting messages to the TACACS+ accounting server when you enter any command other than

show

commands at the CLI.

If you customize the command privilege level using the Command Privilege Setup dialog box (see the

“Assigning Privilege Levels to Commands and Enabling Authorization” section on page 32-17

), you can limit which commands the adaptive security appliance accounts for by specifying a minimum privilege level in the Privilege level drop-down list. The adaptive security appliance does not account for commands that are below the minimum privilege level.

Click

Apply

.

Viewing the Current Logged-In User

To view the current logged-in user, enter the following command in Tools > Command Line Interface:

show curpriv

See the following sample

show curpriv

command output. A description of each field follows.

show curpriv

Username : admin

Current privilege level : 15

Current Mode/s : P_PRIV

Table 32-1

describes the

show curpriv

command output.

Table 32-1

Field

Username

show curpriv Command Output Description

Description

Username. If you are logged in as the default user, the name is enable_1 (user

EXEC) or enable_15 (privileged EXEC).

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Table 32-1 show curpriv Command Output Description

Field Description

Current privilege level Level from 0 to 15. Unless you configure local command authorization and assign commands to intermediate privilege levels, levels 0 and 15 are the only levels that are used.

Current Mode/s Shows the access modes:

•

•

•

P_UNPR—User EXEC mode (levels 0 and 1)

P_PRIV—Privileged EXEC mode (levels 2 to 15)

P_CONF—Configuration mode

Recovering from a Lockout

In some circumstances, when you turn on command authorization or CLI authentication, you can be locked out of the adaptive security appliance CLI. You can usually recover access by restarting the adaptive security appliance. However, if you already saved your configuration, you might be locked out.

Table 32-2 lists the common lockout conditions and how you might recover from them.

Table 32-2

Feature

Local CLI authentication

TACACS+ command authorization

TACACS+ CLI authentication

RADIUS CLI authentication

CLI Authentication and Command Authorization Lockout Scenarios

Lockout Condition Description

No users in the local database

Server down or unreachable and you do not have the fallback method configured

If you have no users in the local database, you cannot log in, and you cannot add any users.

If the server is unreachable, then you cannot log in or enter any commands.

Workaround: Single Mode

Log in and reset the passwords and

aaa

commands.

1.

2.

Log in and reset the passwords and AAA commands.

Configure the local database as a fallback method so you do not get locked out when the server is down.

Workaround: Multiple Mode

Session into the adaptive security appliance from the switch. From the system execution space, you can change to the context and add a user.

1.

If the server is unreachable because the network configuration is incorrect on the adaptive security appliance, session into the adaptive security appliance from the switch. From the system execution space, you can change to the context and reconfigure your network settings.

2.

Configure the local database as a fallback method so you do not get locked out when the server is down.

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Table 32-2

Feature

TACACS+ command authorization

Local command authorization

CLI Authentication and Command Authorization Lockout Scenarios (continued)

Lockout Condition Description

You are logged in as a user without enough privileges or as a user that does not exist

You enable command authorization, but then find that the user cannot enter any more commands.

Workaround: Single Mode

Fix the TACACS+ server user account.

If you do not have access to the TACACS+ server and you need to configure the adaptive security appliance immediately, then log into the maintenance partition and reset the passwords and

aaa

commands.

You are logged in as a user without enough privileges

You enable command authorization, but then find that the user cannot enter any more commands.

Log in and reset the passwords and commands.

aaa

Workaround: Multiple Mode

Session into the adaptive security appliance from the switch. From the system execution space, you can change to the context and complete the configuration changes. You can also disable command authorization until you fix the TACACS+ configuration.

Session into the adaptive security appliance from the switch. From the system execution space, you can change to the context and change the user level.

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C H A P T E R

33

Configuring AAA Rules for Network Access

This chapter describes how to enable AAA (pronounced “triple A”) for network access.

For information about AAA for management access, see the

“Configuring AAA for System

Administrators” section on page 32-10

.


•

AAA Performance, page 33-1

•

•

•

•

Configuring Authentication for Network Access, page 33-1

Configuring Authorization for Network Access, page 33-9

Configuring Accounting for Network Access, page 33-15

Using MAC Addresses to Exempt Traffic from Authentication and Authorization, page 33-16

AAA Performance

The adaptive security appliance uses “cut-through proxy” to significantly improve performance compared to a traditional proxy server. The performance of a traditional proxy server suffers because it analyzes every packet at the application layer of the OSI model. The adaptive security appliance cut-through proxy challenges a user initially at the application layer and then authenticates against standard AAA servers or the local database. After the adaptive security appliance authenticates the user, it shifts the session flow, and all traffic flows directly and quickly between the source and destination while maintaining session state information.

Configuring Authentication for Network Access


•

•

•

•

•

•

Information About Authentication, page 33-2

Configuring Network Access Authentication, page 33-4

Enabling the Redirection Method of Authentication for HTTP and HTTPS, page 33-5

Enabling Secure Authentication of Web Clients, page 33-5

Authenticating Directly with the Adaptive Security Appliance, page 33-6

Configuring the Authentication Proxy Limit, page 33-9


33-1 OL-20339-01

Chapter 33 Configuring AAA Rules for Network Access


Information About Authentication

The adaptive security appliance lets you configure network access authentication using AAA servers.


•

One-Time Authentication, page 33-2

•

•

•

•

•

Applications Required to Receive an Authentication Challenge, page 33-2

Adaptive Security Appliance Authentication Prompts, page 33-2

Static PAT and HTTP, page 33-3

Authenticating Telnet Connections with a Virtual Server, page 33-7

Authenticating HTTP(S) Connections with a Virtual Server, page 33-7

One-Time Authentication

A user at a given IP address only needs to authenticate one time for all rules and types, until the authentication session expires. (See the Configuration > Firewall > Advanced > Global Timeouts pane for timeout values.) For example, if you configure the adaptive security appliance to authenticate Telnet and FTP, and a user first successfully authenticates for Telnet, then as long as the authentication session exists, the user does not also have to authenticate for FTP.

Applications Required to Receive an Authentication Challenge

Although you can configure the adaptive security appliance to require authentication for network access to any protocol or service, users can authenticate directly with HTTP, HTTPS, Telnet, or FTP only. A user must first authenticate with one of these services before the adaptive security appliance allows other traffic requiring authentication.

The authentication ports that the adaptive security appliance supports for AAA are fixed:

•

Port 21 for FTP

•

•

•

Port 23 for Telnet

Port 80 for HTTP

Port 443 for HTTPS

Adaptive Security Appliance Authentication Prompts

For Telnet and FTP, the adaptive security appliance generates an authentication prompt.

For HTTP, the adaptive security appliance uses basic HTTP authentication by default, and provides an authentication prompt. You can optionally configure the adaptive security appliance to redirect users to an internal web page where they can enter their username and password (configured on the Configuration

> Firewall > AAA Rules > Advanced > AAA Rules Advanced Options dialog box; see the

“Enabling the

Redirection Method of Authentication for HTTP and HTTPS” section on page 33-5

).

For HTTPS, the adaptive security appliance generates a custom login screen. You can optionally configure the adaptive security appliance to redirect users to an internal web page where they can enter their username and password (configured on the Configuration > Firewall > AAA Rules > Advanced >

AAA Rules Advanced Options dialog box; see the “Enabling the Redirection Method of Authentication for HTTP and HTTPS” section on page 33-5 ).

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Redirection is an improvement over the basic method because it provides an improved user experience when authenticating, and an identical user experience for HTTP and HTTPS in both Easy VPN and firewall modes. It also supports authenticating directly with the adaptive security appliance.

You might want to continue to use basic HTTP authentication if: you do not want the adaptive security appliance to open listening ports; if you use NAT on a router and you do not want to create a translation rule for the web page served by the adaptive security appliance; basic HTTP authentication might work better with your network. For example non-browser applications, like when a URL is embedded in email, might be more compatible with basic authentication.

After you authenticate correctly, the adaptive security appliance redirects you to your original destination. If the destination server also has its own authentication, the user enters another username and password. If you use basic HTTP authentication and need to enter another username and password for the destination server, then you need to configure virtual HTTP (see the Configuration >Firewall >

Advanced Options > Virtual Access pane).

Note

If you use HTTP authentication, by default the username and password are sent from the client to the adaptive security appliance in clear text; in addition, the username and password are sent on to the

destination web server as well. See the “Enabling Secure Authentication of Web Clients” section on page 33-5

for information to secure your credentials.

For FTP, a user has the option of entering the adaptive security appliance username followed by an at sign (@) and then the FTP username (name1@name2). For the password, the user enters the adaptive security appliance password followed by an at sign (@) and then the FTP password

(password1@password2). For example, enter the following text.

name>

jamiec@patm

password>

letmein@he110

This feature is useful when you have cascaded firewalls that require multiple logins. You can separate several names and passwords by multiple at signs (@).

Static PAT and HTTP

For HTTP authentication, the adaptive security appliance checks real ports when static PAT is configured. If it detects traffic destined for real port 80, regardless of the mapped port, the adaptive security appliance intercepts the HTTP connection and enforces authentication.

For example, assume that outside TCP port 889 is translated to port 80 (www) and that any relevant access lists permit the traffic: static (inside,outside) tcp 10.48.66.155 889 192.168.123.10 www netmask 255.255.255.255

Then when users try to access 10.48.66.155 on port 889, the adaptive security appliance intercepts the traffic and enforces HTTP authentication. Users see the HTTP authentication page in their web browsers before the adaptive security appliance allows HTTP connection to complete.

If the local port is different than port 80, as in the following example: static (inside,outside) tcp 10.48.66.155 889 192.168.123.10 111 netmask 255.255.255.255

Then users do not see the authentication page. Instead, the adaptive security appliance sends to the web browser an error message indicating that the user must be authenticated prior using the requested service.

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Configuring Network Access Authentication

To enable network access authentication, perform the following steps. For more information about authentication, see the

“Information About Authentication” section on page 33-2 .

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

From the Configuration > Firewall > AAA Rules pane, choose

Add > Add Authentication Rule

.

The Add Authentication Rule dialog box appears.

From the Interface drop-down list, choose the interface for applying the rule.

In the Action field, click one of the following, depending on the implementation:

•

•

Authenticate

Do not Authenticate

.

From the AAA Server Group drop-down list, choose a server group. To add a AAA server to the server group, click

Add Server

. See the

“Configuring AAA Server Groups” section on page 31-8


If you chose LOCAL for the AAA server group, you can optionally add a new user by clicking

Add User

.

See the

“Adding a User Account” section on page 31-18 for more information.

In the Source field, add the source IP address, or click the ellipsis (...) to choose an IP address already defined in ASDM.

In the Destination field, enter the destination IP address, or click the ellipsis (...) to choose an IP address already defined in ASDM.

In the Service field, enter an IP service name or number for the destination service, or click ellipsis (...) button to choose a service.

(Optional) In the Description field, add a description.

(Optional) Click

More Options

to do any of the following:

•

To specify a source service for TCP or UDP, enter a TCP or UDP service in the Source Service field.

•

•


To make the rule inactive, uncheck

Enable Rule

.

You may not want to remove a rule, but instead turn it off.

To set a time range for the rule, from the Time Range drop-down list, choose an existing time range.

To add a new time range, click the ellipsis (...). For more information, see the “Configuring Time

Ranges” section on page 13-15 .

Click

OK

.

The dialog box closes and the rule appears in the AAA Rules table.

Click

Apply

.


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Enabling the Redirection Method of Authentication for HTTP and HTTPS

This method of authentication enables HTTP(S) listening ports to authenticate network users. When you enable a listening port, the adaptive security appliance serves an authentication page for direct connections and, by enabling redirection, for through traffic. This method also prevents the authentication credentials from continuing to the destination server. See the

“Adaptive Security

Appliance Authentication Prompts” section on page 33-2

for more information about the redirection method versus the basic method.

To enable a AAA listener, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

From the Configuration > Firewall > AAA Rules pane, click

Advanced

.

The AAA Rules Advanced Options dialog box appears.

Under Interactive Authentication, click

Add

.

The Add Interactive Authentication Entry dialog box appears.

For the Protocol, choose either

HTTP

or

HTTPS

. You can enable both by repeating this procedure and creating two separate rules.

From the Interface drop-down list, choose the interface on which you want to enable the listener.

From the Port drop-down list, choose the port or enter a number.

This is the port that the adaptive security appliance listens on for direct or redirected traffic; the defaults are 80 (HTTP) and 443 (HTTPS). You can use any port number and retain the same functionality, but be sure your direct authentication users know the port number; redirected traffic is sent to the correct port number automatically, but direct authenticators must specify the port number manually.

(Optional) Check

Redirect network users for authentication request

.

This option redirects through traffic to an authentication web page served by the adaptive security appliance. Without this option, only traffic directed to the adaptive security appliance interface can access the authentication web pages.

Step 7

Step 8

Note

If you enable the redirect option, you cannot also configure static PAT for the same interface where you translate the interface IP address and the same port that is used for the listener; NAT succeeds, but authentication fails.

Click

OK

, and then click

OK

to exit the AAA Rules Advanced Options dialog box.

Click

Apply

.

Enabling Secure Authentication of Web Clients

If you use HTTP authentication, by default the username and password are sent from the client to the adaptive security appliance in clear text; in addition, the username and password are sent on to the destination web server as well. The adaptive security appliance provides several methods of securing

HTTP authentication, including the following methods:

•

Enable the redirection method of authentication for HTTP—See the “Enabling the Redirection

Method of Authentication for HTTP and HTTPS” section on page 33-5 . This method prevents the

authentication credentials from continuing to the destination server.

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33-5



•

•

Enabling Virtual HTTP—Virtual HTTP lets you authenticate separately with the adaptive security appliance and with the HTTP server. Even if the HTTP server does not need a second authentication, this feature achieves the effect of stripping the basic authentication credentials from the HTTP GET request. See the

“Authenticating HTTP(S) Connections with a Virtual Server” section on page 33-7


Enabling the Exchange of Usernames and Passwords Using HTTPS—To enable the exchange of usernames and passwords between a web client and the adaptive security appliance with HTTPS, perform the following steps:

a.


Advanced

. The AAA Rules

Advanced Options dialog box appears.

b.

Under Secure HTTP, click

Enable Secure HTTP

.

c.

Click

OK

, and then click

OK

to exit the AAA Rules Advanced Options dialog box. Click

Apply

.

This is the only method that protects credentials between the client and the adaptive security appliance, as well as between the adaptive security appliance and the destination server. You can use this method alone, or in conjunction with either of the other methods so you can maximize your security.

After enabling this feature, when a user requires authentication when using HTTP, the adaptive security appliance redirects the HTTP user to an HTTPS prompt. After you authenticate correctly, the adaptive security appliance redirects you to the original HTTP URL.

Secured web-client authentication has the following limitations:

–

A maximum of 16 concurrent HTTPS authentication sessions are allowed. If all 16 HTTPS authentication processes are running, a new connection requiring authentication will not succeed.

–

–

When the uauth timeout is set to unlimited, HTTPS authentication might not work. If a browser initiates multiple TCP connections to load a web page after HTTPS authentication, the first connection is let through, but the subsequent connections trigger authentication. As a result, users are continuously presented with an authentication page, even if the correct username and password are entered each time. To work around this, set the uauth timeout to 1 second (see the

Configuration > Firewall > Advanced > Global Timeouts pane). However, this workaround opens a 1-second window of opportunity that might allow non-authenticated users to go through the firewall if they are coming from the same source IP address.

Because HTTPS authentication occurs on the SSL port 443, users must not configure an Access

Rule to block traffic from the HTTP client to HTTP server on port 443. Furthermore, if static

PAT is configured for web traffic on port 80, it must also be configured for the SSL port.

Authenticating Directly with the Adaptive Security Appliance

If you do not want to allow HTTP, HTTPS, Telnet, or FTP through the adaptive security appliance but want to authenticate other types of traffic, you can authenticate with the adaptive security appliance directly using HTTP, HTTPS, or Telnet.

•

Authenticating Telnet Connections with a Virtual Server, page 33-7

•

Authenticating HTTP(S) Connections with a Virtual Server, page 33-7

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Authenticating Telnet Connections with a Virtual Server

Although you can configure network access authentication for any protocol or service (see the

“Configuring Authentication for Network Access” section on page 33-1

), you can authenticate directly with HTTP, Telnet, or FTP only. A user must first authenticate with one of these services before other traffic that requires authentication is allowed through. If you do not want to allow HTTP, Telnet, or FTP through the adaptive security appliance, but want to authenticate other types of traffic, you can configure virtual Telnet; the user Telnets to a given IP address configured on the adaptive security appliance, and the adaptive security appliance provides a Telnet prompt.

You must configure authentication for Telnet access to the virtual Telnet address as well as the other services you want to authenticate according to the

“Configuring Authentication for Network Access” section on page 33-1 .

When an unauthenticated user connects to the virtual Telnet IP address, the user is challenged for a username and password, and then authenticated by the AAA server. Once authenticated, the user sees the message “Authentication Successful.” Then, the user can successfully access other services that require authentication.

For inbound users (from lower security to higher security), you must also include the virtual Telnet address as a destination interface in the Access Rule applied to the source interface. Moreover, you must add a static NAT rule for the virtual Telnet IP address, even if NAT is not required. An identity NAT rule is typically used (where you translate the address to itself).

For outbound users, there is an explicit permit for traffic, but if you apply an Access Rule to an inside interface, be sure to allow access to the virtual Telnet address. A static NAT rule is not required.

To logout from the adaptive security appliance, reconnect to the virtual Telnet IP address; you are prompted to log out.

To enable direct authentication using Telnet, perform the following steps:

Step 1

Step 2

Step 3

From the Configuration > Firewall > Advanced > Virtual Access > Virtual Telnet Server area, check the

Enable

check box.

In the Virtual Telnet Server field, add the IP address of the virtual Telnet server.

Make sure this address is an unused address that is routed to the adaptive security appliance. For example, if you perform NAT for inside addresses accessing an outside server, and you want to provide outside access to the virtual HTTP server, you can use one of the global NAT addresses for the virtual

HTTP server address.

Click

Apply

.

The virtual server is added and the changes are saved to the running configuration.

Authenticating HTTP(S) Connections with a Virtual Server

When you use HTTP authentication on the adaptive security appliance (see the

“Configuring

Authentication for Network Access” section on page 33-1 ), the adaptive security appliance uses basic

HTTP authentication by default. You can change the authentication method so that the adaptive security appliance redirects HTTP connections to web pages generated by the adaptive security appliance itself

using the “Enabling the Redirection Method of Authentication for HTTP and HTTPS” section on page 33-5

.

However, if you continue to use basic HTTP authentication, then you might need the virtual HTTP server when you have cascading HTTP authentications.


OL-20339-01 33-7



If the destination HTTP server requires authentication in addition to the adaptive security appliance, then virtual HTTP lets you authenticate separately with the adaptive security appliance (via a AAA server) and with the HTTP server. Without virtual HTTP, the same username and password you used to authenticate with the adaptive security appliance is sent to the HTTP server; you are not prompted separately for the HTTP server username and password. Assuming the username and password is not the same for the AAA and HTTP servers, then the HTTP authentication fails.

This feature redirects all HTTP connections that require AAA authentication to the virtual HTTP server on the adaptive security appliance. The adaptive security appliance prompts for the AAA server username and password. After the AAA server authenticates the user, the adaptive security appliance redirects the HTTP connection back to the original server, but it does not include the AAA server username and password. Because the username and password are not included in the HTTP packet, the

HTTP server prompts the user separately for the HTTP server username and password.

For inbound users (from lower security to higher security), you must also include the virtual HTTP address as a destination interface in the Access Rule applied to the source interface. Moreover, you must add a static NAT rule for the virtual HTTP IP address, even if NAT is not required. An identity NAT rule is typically used (where you translate the address to itself).

For outbound users, there is an explicit permit for traffic, but if you apply an Access Rule to an inside interface, be sure to allow access to the virtual HTTP address. A static NAT rule is not required.

Note

Do not set the uauth timeout duration to 0 seconds when using virtual HTTP, because this setting prevents HTTP connections to the real web server. See the

“Configuring Global Timeouts” section on page 48-9 .

You can authenticate directly with the adaptive security appliance at the following URLs when you enable AAA for the interface:

http://

interface_ip

[

:

port

]

/netaccess/connstatus.html

https://

interface_ip

[

:

port

]

/netaccess/connstatus.html

To allow users to authenticate with the adaptive security appliance virtual server separately from the

HTTP server, perform the following steps:

Step 1

Step 2

Step 3

Step 4

From the Configuration > Firewall > Advanced > Virtual Access > Virtual HTTP Server area, check the

Enable

check box.

In the Virtual HTTP Server field, add the IP address of the virtual HTTP server.

Make sure this address is an unused address that is routed to the adaptive security appliance. For example, if you perform NAT for inside addresses accessing an outside server, and you want to provide outside access to the virtual HTTP server, you can use one of the global NAT addresses for the virtual

HTTP server address.

(Optional) If you are using text-based browsers, where redirection does not happen automatically, check the

Display redirection warning

check box. This enables an alert to notify users when the HTTP connection is being redirected.

Click

Apply

.

The virtual server is added and the changes are saved to the running configuration.

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Configuring Authorization for Network Access

Configuring the Authentication Proxy Limit

You can manually configure the uauth session limit by setting the maximum number of concurrent proxy connections allowed per user.

To set the proxy limit, perform the following steps:

Step 1

Step 2

Step 3

Step 4


Advanced

.

The AAA Rules Advanced Options dialog box appears.

In the Proxy Limit area, check

Enable Proxy Limit

.

In the Proxy Limit field, enter the number of concurrent proxy connections allowed per user, from 1 to

128.

Click

OK

, and then click

Apply

.


After a user authenticates for a given connection, the adaptive security appliance can use authorization to further control traffic from the user.


•

Configuring TACACS+ Authorization, page 33-9

•

Configuring RADIUS Authorization, page 33-10

Configuring TACACS+ Authorization

You can configure the adaptive security appliance to perform network access authorization with

TACACS+.

Authentication and authorization rules are independent; however, any unauthenticated traffic matched by an authorization rule will be denied. For authorization to succeed:

1.

A user must first authenticate with the adaptive security appliance.

2.

Because a user at a given IP address only needs to authenticate one time for all rules and types, if the authentication session hasn’t expired, authorization can occur even if the traffic is not matched by an authentication rule.

After a user authenticates, the adaptive security appliance checks the authorization rules for matching traffic.

3.

4.

If the traffic matches the authorization rule, the adaptive security appliance sends the username to the TACACS+ server.

The TACACS+ server responds to the adaptive security appliance with a permit or a deny for that traffic, based on the user profile.

5.

The adaptive security appliance enforces the authorization rule in the response.

See the documentation for your TACACS+ server for information about configuring network access authorizations for a user.

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To configure TACACS+ authorization, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Step 12

Enable authentication. For more information, see the

“Configuring Authentication for Network Access” section on page 33-1 . If you have already enabled authentication, continue to the next step.


Add > Add Authorization Rule

.

The Add Authorization Rule dialog box appears.



•

•

Authorize

Do not Authorize

.


Add Server

. See the



Only TACACS+ servers are supported.





(Optional) Click

More Options


•


•

•



Enable Rule

.





Click

OK

.


Click

Apply

.


Configuring RADIUS Authorization

When authentication succeeds, the RADIUS protocol returns user authorizations in the access-accept message sent by a RADIUS server. For more information about configuring authentication, see the

“Configuring Authentication for Network Access” section on page 33-1 .

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When you configure the adaptive security appliance to authenticate users for network access, you are also implicitly enabling RADIUS authorizations; therefore, this section contains no information about configuring RADIUS authorization on the adaptive security appliance. It does provide information about how the adaptive security appliance handles access list information received from RADIUS servers.

You can configure a RADIUS server to download an access list to the adaptive security appliance or an access list name at the time of authentication. The user is authorized to do only what is permitted in the user-specific access list.

Note

If you have enabled the Per User Override Setting (see the Configuration > Firewall > Access Rules >

Advanced > Access Rules Advanced Options dialog box), be aware of the following effects of this feature on authorization by user-specific access lists:

•

•

Without the per-user-override feature, traffic for a user session must be permitted by both the interface access list and the user-specific access list.

With the per-user-override feature, the user-specific access list determines what is permitted.


•

Configuring a RADIUS Server to Send Downloadable Access Control Lists, page 33-11

•

Configuring a RADIUS Server to Download Per-User Access Control List Names, page 33-15

Configuring a RADIUS Server to Send Downloadable Access Control Lists

This section describes how to configure Cisco Secure ACS or a third-party RADIUS server and includes the following topics:

•

•

•

•

About the Downloadable Access List Feature and Cisco Secure ACS, page 33-11

Configuring Cisco Secure ACS for Downloadable Access Lists, page 33-13

Configuring Any RADIUS Server for Downloadable Access Lists, page 33-14

Converting Wildcard Netmask Expressions in Downloadable Access Lists, page 33-15

About the Downloadable Access List Feature and Cisco Secure ACS

Downloadable access lists is the most scalable means of using Cisco Secure ACS to provide the appropriate access lists for each user. It provides the following capabilities:

•

Unlimited access list size—Downloadable access lists are sent using as many RADIUS packets as required to transport the full access list from Cisco Secure ACS to the adaptive security appliance.

•

Simplified and centralized management of access lists—Downloadable access lists enable you to write a set of access lists once and apply it to many user or group profiles and distribute it to many adaptive security appliances.

This approach is most useful when you have very large access list sets that you want to apply to more than one Cisco Secure ACS user or group; however, its ability to simplify Cisco Secure ACS user and group management makes it useful for access lists of any size.

The adaptive security appliance receives downloadable access lists from Cisco Secure ACS using the following process:

1.

The adaptive security appliance sends a RADIUS authentication request packet for the user session.

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2.

If Cisco Secure ACS successfully authenticates the user, Cisco Secure ACS returns a RADIUS access-accept message that contains the internal name of the applicable downloadable access list.

The Cisco IOS cisco-av-pair RADIUS VSA (vendor 9, attribute 1) contains the following attribute-value pair to identify the downloadable access list set:

ACS:CiscoSecure-Defined-ACL=

acl-set-name

3.

where

acl-set-name

is the internal name of the downloadable access list, which is a combination of the name assigned to the access list by the Cisco Secure ACS administrator and the date and time that the access list was last modified.

The adaptive security appliance examines the name of the downloadable access list and determines if it has previously received the named downloadable access list.

–

–

If the adaptive security appliance has previously received the named downloadable access list, communication with Cisco Secure ACS is complete and the adaptive security appliance applies the access list to the user session. Because the name of the downloadable access list includes the date and time it was last modified, matching the name sent by Cisco Secure ACS to the name of an access list previous downloaded means that the adaptive security appliance has the most recent version of the downloadable access list.

If the adaptive security appliance has not previously received the named downloadable access list, it may have an out-of-date version of the access list or it may not have downloaded any version of the access list. In either case, the adaptive security appliance issues a RADIUS authentication request using the downloadable access list name as the username in the RADIUS request and a null password attribute. In a cisco-av-pair RADIUS VSA, the request also includes the following attribute-value pairs:

AAA:service=ip-admission

AAA:event=acl-download

4.

5.

In addition, the adaptive security appliance signs the request with the Message-Authenticator attribute (IETF RADIUS attribute 80).

Upon receipt of a RADIUS authentication request that has a username attribute containing the name of a downloadable access list, Cisco Secure ACS authenticates the request by checking the

Message-Authenticator attribute. If the Message-Authenticator attribute is missing or incorrect,

Cisco Secure ACS ignores the request. The presence of the Message-Authenticator attribute prevents malicious use of a downloadable access list name to gain unauthorized network access. The

Message-Authenticator attribute and its use are defined in RFC 2869, RADIUS Extensions, available at http://www.ietf.org

.

If the access list required is less than approximately 4 KB in length, Cisco Secure ACS responds with an access-accept message containing the access list. The largest access list that can fit in a single access-accept message is slightly less than 4 KB because some of the message must be other required attributes.

Cisco Secure ACS sends the downloadable access list in a cisco-av-pair RADIUS VSA. The access list is formatted as a series of attribute-value pairs that each contain an ACE and are numbered serially:

.

.

.

ip:inacl#1=

ACE-1

ip:inacl#2=

ACE-2

ip:inacl#

n

=

ACE-n

An example of an attribute-value pair follows: ip:inacl#1=permit tcp 10.1.0.0 255.0.0.0 10.0.0.0 255.0.0.0

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6.

If the access list required is more than approximately 4 KB in length, Cisco Secure ACS responds with an access-challenge message that contains a portion of the access list, formatted as described above, and an State attribute (IETF RADIUS attribute 24), which contains control data used by

Cisco Secure ACS to track the progress of the download. Cisco Secure ACS fits as many complete attribute-value pairs into the cisco-av-pair RADIUS VSA as it can without exceeding the maximum

RADIUS message size.

The adaptive security appliance stores the portion of the access list received and responds with another access-request message containing the same attributes as the first request for the downloadable access list plus a copy of the State attribute received in the access-challenge message.

This repeats until Cisco Secure ACS sends the last of the access list in an access-accept message.

Configuring Cisco Secure ACS for Downloadable Access Lists

You can configure downloadable access lists on Cisco Secure ACS as a shared profile component and then assign the access list to a group or to an individual user.

The access list definition consists of one or more adaptive security appliance commands that are similar to the extended

access-list

command, except without the following prefix:

access-list

acl_name

extended

The following example is a downloadable access list definition on Cisco Secure ACS version 3.3:

+--------------------------------------------+

| Shared profile Components |

| |

| Downloadable IP ACLs Content |

| |

| Name: acs_ten_acl |

| |

| ACL Definitions |

| |

| permit tcp any host 10.0.0.254 |

| permit udp any host 10.0.0.254 |

| permit icmp any host 10.0.0.254 |







| permit ip any any |

+--------------------------------------------+

For more information about creating downloadable access lists and associating them with users, see the user guide for your version of Cisco Secure ACS.

On the adaptive security appliance, the downloaded access list has the following name:

#ACSACL#-ip-

acl_name

-

number

The

acl_name

argument is the name that is defined on Cisco Secure ACS (acs_ten_acl in the preceding example), and

number

is a unique version ID generated by Cisco Secure ACS.

The downloaded access list on the adaptive security appliance consists of the following lines: access-list #ACSACL#-ip-asa-acs_ten_acl-3b5385f7 permit tcp any host 10.0.0.254

access-list #ACSACL#-ip-asa-acs_ten_acl-3b5385f7 permit udp any host 10.0.0.254

access-list #ACSACL#-ip-asa-acs_ten_acl-3b5385f7 permit icmp any host 10.0.0.254

access-list #ACSACL#-ip-asa-acs_ten_acl-3b5385f7 permit tcp any host 10.0.0.253

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access-list #ACSACL#-ip-asa-acs_ten_acl-3b5385f7 permit tcp any host 10.0.0.252



access-list #ACSACL#-ip-asa-acs_ten_acl-3b5385f7 permit ip any any

Configuring Any RADIUS Server for Downloadable Access Lists

You can configure any RADIUS server that supports Cisco IOS RADIUS VSAs to send user-specific access lists to the adaptive security appliance in a Cisco IOS RADIUS cisco-av-pair VSA (vendor 9, attribute 1).

In the cisco-av-pair VSA, configure one or more ACEs that are similar to the

access-list extended

command, except that you replace the following command prefix:

access-list

acl_name

extended

with the following text:

ip:inacl#

nnn

=

The

nnn

argument is a number in the range from 0 to 999999999 that identifies the order of the command statement to be configured on the adaptive security appliance. If this parameter is omitted, the sequence value is 0, and the order of the ACEs inside the cisco-av-pair RADIUS VSA is used.

The following example is an access list definition as it should be configured for a cisco-av-pair VSA on a RADIUS server: ip:inacl#1=permit tcp 10.1.0.0 255.0.0.0 10.0.0.0 255.0.0.0

ip:inacl#99=deny tcp any any ip:inacl#2=permit udp 10.1.0.0 255.0.0.0 10.0.0.0 255.0.0.0

ip:inacl#100=deny udp any any ip:inacl#3=permit icmp 10.1.0.0 255.0.0.0 10.0.0.0 255.0.0.0

For information about making unique per user the access lists that are sent in the cisco-av-pair attribute, see the documentation for your RADIUS server.

On the adaptive security appliance, the downloaded access list name has the following format:

AAA-user-

username

The

username

argument is the name of the user that is being authenticated.

The downloaded access list on the adaptive security appliance consists of the following lines. Notice the order based on the numbers identified on the RADIUS server.

access-list AAA-user-bcham34-79AD4A08 permit tcp 10.1.0.0 255.0.0.0 10.0.0.0 255.0.0.0

access-list AAA-user-bcham34-79AD4A08 permit udp 10.1.0.0 255.0.0.0 10.0.0.0 255.0.0.0

access-list AAA-user-bcham34-79AD4A08 permit icmp 10.1.0.0 255.0.0.0 10.0.0.0 255.0.0.0

access-list AAA-user-bcham34-79AD4A08 deny tcp any any access-list AAA-user-bcham34-79AD4A08 deny udp any any

Downloaded access lists have two spaces between the word “access-list” and the name. These spaces serve to differentiate a downloaded access list from a local access list. In this example, “79AD4A08” is a hash value generated by the adaptive security appliance to help determine when access list definitions have changed on the RADIUS server.

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Configuring Accounting for Network Access

Converting Wildcard Netmask Expressions in Downloadable Access Lists

If a RADIUS server provides downloadable access lists to Cisco VPN 3000 series concentrators as well as to the adaptive security appliance, you may need the adaptive security appliance to convert wildcard netmask expressions to standard netmask expressions. This is because Cisco VPN 3000 series concentrators support wildcard netmask expressions but the adaptive security appliance only supports standard netmask expressions. Configuring the adaptive security appliance to convert wildcard netmask expressions helps minimize the effects of these differences upon how you configure downloadable access lists on your RADIUS servers. Translation of wildcard netmask expressions means that downloadable access lists written for Cisco VPN 3000 series concentrators can be used by the adaptive security appliance without altering the configuration of the downloadable access lists on the RADIUS server.

You configure access list netmask conversion on a per-server basis when you add a server to a server group, on the Configuration > Device Management > Users/AAA > AAA Server Groups > AAA Server

Groups area. See the

“Adding a Server Group” section on page 31-8 .

Configuring a RADIUS Server to Download Per-User Access Control List Names

To download a name for an access list that you already created on the adaptive security appliance (at the

CLI) from the RADIUS server when a user authenticates, configure the IETF RADIUS filter-id attribute

(attribute number 11) as follows:

filter-id=

acl_name

Note

In Cisco Secure ACS, the value for filter-id attributes are specified in boxes in the HTML interface, omitting

filter-id=

and entering only

acl_name

.

For information about making unique per user the filter-id attribute value, see the documentation for your

RADIUS server.

See the


to create an access list on the adaptive security appliance.

Configuring Accounting for Network Access

The adaptive security appliance can send accounting information to a RADIUS or TACACS+ server about any TCP or UDP traffic that passes through the adaptive security appliance. If that traffic is also authenticated, then the AAA server can maintain accounting information by username. If the traffic is not authenticated, the AAA server can maintain accounting information by IP address. Accounting information includes when sessions start and stop, username, the number of bytes that pass through the adaptive security appliance for the session, the service used, and the duration of each session.

To configure accounting, perform the following steps:

Step 1

Step 2

If you want the adaptive security appliance to provide accounting data per user, you must enable authentication. For more information, see the

“Configuring Authentication for Network Access” section on page 33-1 . If you want the adaptive security appliance to provide accounting data per IP address,

enabling authentication is not necessary and you can continue to the next step.


Add > Add Accounting Rule

.

The Add Accounting Rule dialog box appears.


OL-20339-01 33-15


Using MAC Addresses to Exempt Traffic from Authentication and Authorization

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Step 12



•

Account

• Do not Account

.


Add Server

. See the







(Optional) Click

More Options


•


•

•



Enable Rule

.





Click

OK

.


Click

Apply

.



The adaptive security appliance can exempt from authentication and authorization any traffic from specific MAC addresses.

For example, if the adaptive security appliance authenticates TCP traffic originating on a particular network but you want to allow unauthenticated TCP connections from a specific server, you would use a MAC exempt rule to exempt from authentication and authorization any traffic from the server specified by the rule. This feature is particularly useful to exempt devices such as IP phones that cannot respond to authentication prompts.

33-16


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Step 13

Step 14

Step 15

Step 16

Step 17

Step 18

The order of entries matters, because the packet uses the first entry it matches, as opposed to a best match scenario. If you have a permit entry, and you want to deny an address that is allowed by the permit entry, be sure to enter the deny entry before the permit entry.

To use MAC addresses to exempt traffic from authentication and authorization, perform the following steps:


Add > Add MAC Exempt Rule

.

The Add MAC Exempt Rule dialog box appears.

From the Action drop-down list, click one of the following, depending on the implementation:

•

•

MAC Exempt

No MAC Exempt

The MAC Exempt option allows traffic from the MAC address without having to authenticate or authorize. The No MAC Exempt option specifies a MAC address that is not exempt from authentication or authorization. You might need to add a deny entry if you permit a range of MAC addresses using a

MAC address mask such as ffff.ffff.0000, and you want to force a MAC address in that range to be authenticated and authorized.

In the MAC Address field, specify the source MAC address in 12-digit hexadecimal form; that is, nnnn.nnnn.nnnn.

In the MAC Mask field, specify the portion of the MAC address that should be used for matching. For example, ffff.ffff.ffff matches the MAC address exactly. ffff.ffff.0000 matches only the first 8 digits.

Click

OK

.


Click

Apply

.


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C H A P T E R

34

Configuring Filtering Services

This chapter describes how to use filtering services to provide greater control over traffic passing through the adaptive security appliance and includes the following sections:

•

Information About Web Traffic Filtering, page 34-1

•

•

•

•

Configuring Filtering Rules, page 34-6

Filtering the Rule Table, page 34-11

Defining Queries, page 34-12

Filtering URLs and FTP Requests with an External Server, page 34-2

Information About Web Traffic Filtering

You can use web traffic filtering in two distinct ways:

•

•

Filtering ActiveX objects or Java applets

Filtering with an external filtering server

Instead of blocking access altogether, you can remove specific undesirable objects from web traffic, such as ActiveX objects or Java applets, that may pose a security threat in certain situations.

You can use web traffic filtering to direct specific traffic to an external filtering server, such an Secure

Computing SmartFilter (formerly N2H2) or the Websense filtering server. You can enable long URL,

HTTPS, and FTP filtering using either Websense or Secure Computing SmartFilter for web traffic filtering. Filtering servers can block traffic to specific sites or types of sites, as specified by the security policy.

Note

URL caching will only work if the version of the URL server software from the URL server vendor supports it.

Because web traffic filtering is CPU-intensive, using an external filtering server ensures that the throughput of other traffic is not affected. However, depending on the speed of your network and the capacity of your web traffic filtering server, the time required for the initial connection may be noticeably slower when filtering traffic with an external filtering server.


34-1 OL-20339-01

Chapter 34 Configuring Filtering Services

Filtering URLs and FTP Requests with an External Server


This section describes how to filter URLs and FTP requests with an external server and includes the following topics:

•

Information About URL Filtering, page 34-2

•

•

•

•

•

Licensing Requirements for URL Filtering, page 34-3

Guidelines and Limitations for URL Filtering, page 34-3

Identifying the Filtering Server, page 34-3

Configuring Additional URL Filtering Settings, page 34-4

Feature History for URL Filtering, page 34-12

Information About URL Filtering

You can apply filtering to connection requests originating from a more secure network to a less secure network. Although you can use ACLs to prevent outbound access to specific content servers, managing usage this way is difficult because of the size and dynamic nature of the Internet. You can simplify configuration and improve adaptive security appliance performance by using a separate server running one of the following Internet filtering products:

•

•

Websense Enterprise for filtering HTTP, HTTPS, and FTP.

Secure Computing SmartFilter (formerly N2H2) for filtering HTTP, HTTPS, FTP, and long URL filtering.

Note

URL caching will only work if the version of the URL server software from the URL server vendor supports it.

Although adaptive security appliance performance is less affected when using an external server, you may notice longer access times to websites or FTP servers when the filtering server is remote from the adaptive security appliance.

When filtering is enabled and a request for content is directed through the adaptive security appliance, the request is sent to the content server and to the filtering server at the same time. If the filtering server allows the connection, the adaptive security appliance forwards the response from the content server to the originating client. If the filtering server denies the connection, the adaptive security appliance drops the response and sends a message or return code indicating that the connection was not successful.

If user authentication is enabled on the adaptive security appliance, then the adaptive security appliance also sends the username to the filtering server. The filtering server can use user-specific filtering settings or provide enhanced reporting about usage.

34-2


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Licensing Requirements for URL Filtering

The following table shows the licensing requirements for URL filtering:


Model

All models


Base License.

Guidelines and Limitations for URL Filtering






IPv6 Guidelines

Supports IPv6.

Identifying the Filtering Server

You can identify up to four filtering servers per context. The adaptive security appliance uses the servers in order until a server responds. In single mode, a maximum of 16 of the same type of filtering servers are allowed. You can only configure a single type of server (Websense or Secure Computing SmartFilter) in your configuration.

Note

You must add the filtering server before you can configure filtering for HTTP or HTTPS.

To specify the external filtering server, perform the following steps:

Step 1

Step 2

Step 3

Step 4

In the ASDM main window, choose

Configuration > Firewall > URL Filtering Servers

.

In the URL Filtering Server Type area, click one of the following options:

•

Websense

• Secure Computing SmartFilter

If you chose the second option, enter the Secure Computing SmartFilter port number if it is different than the default port number, which is 4005.

In the URL Filtering Servers area, click

Add

.

If you chose the Websense option, the Add Parameters for Websense URL Filtering dialog box appears.

•

•

Choose the interface on which the URL filtering server is connected from the drop-down list.

Enter the IP address of the URL filtering server.

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•

•

Enter the number of seconds after which the request to the URL filtering server times out. The default is 30 seconds.

In the Protocol area, to specify which TCP version to use to communicate with the URL filtering server, click one of the following radio buttons:

–

TCP 1

–

–

TCP 4

UDP 4

•

Enter the maximum number of TCP connections allowed for communicating with the URL filtering server, and click

OK

.

The new Websense URL filtering server properties appear in the URL Filtering Servers pane. To change these properties, click

Edit

. To add more Websense URL filtering servers after you have added the first

Websense URL filtering server, click

Add

or

Insert

. To remove a Websense URL filtering server, click

Delete

.

If you chose the Secure Computing SmartFilter URL Filtering option, the Add Parameters for Secure

Computing SmartFilter URL Filtering dialog box appears.

•

Choose the interface on which the URL filtering server is connected from the drop-down list.

•

•

Enter the IP address of the URL filtering server.

Enter the number of seconds after which the request to the URL filtering server times out. The default is 30 seconds.

•

•

In the Protocol area, to specify which protocol type to use to communicate with the URL filtering server, click one of the following radio buttons:

–

TCP

–

UDP

Enter the maximum number of TCP connections allowed for communicating with the URL filtering server, and click

OK

.

The new Secure Computing SmartFilter URL filtering server properties appear in the URL Filtering

Servers pane. To change these properties, click

Edit

. To add more Secure Computing SmartFilter URL filtering servers after you have defined the first Secure Computing SmartFilter URL filtering server, click

Add

or

Insert

. To remove a Secure Computing SmartFilter URL filtering server, click

Delete

.

Configuring Additional URL Filtering Settings

After you have accessed a website, the filtering server can allow the adaptive security appliance to cache the server address for a certain period of time, as long as each website hosted at the address is in a category that is permitted at all times. When you access the server again, or if another user accesses the server, the adaptive security appliance does not need to consult the filtering server again to obtain the server address.

Note

Requests for cached IP addresses are not passed to the filtering server and are not logged.

As a result, this activity does not appear in any reports.

This section describes how to configure additional URL filtering settings and includes the following topics:


34-4 OL-20339-01



•

•

•

Buffering the Content Server Response, page 34-5

Caching Server Addresses, page 34-5

Filtering HTTP URLs, page 34-6

Buffering the Content Server Response

When you issue a request to connect to a content server, the adaptive security appliance sends the request to the content server and to the filtering server at the same time. If the filtering server does not respond before the content server, the server response is dropped. This behavior delays the web server response for the web client, because the web client must reissue the request.

By enabling the HTTP response buffer, replies from web content servers are buffered, and the responses are forwarded to the requesting client if the filtering server allows the connection. This behavior prevents the delay that might otherwise occur.

To configure buffering for responses to HTTP or FTP requests, perform the following steps:

Step 1

Step 2

Step 3

Step 4

In the URL Filtering Servers pane, click

Advanced

to display the Advanced URL Filtering dialog box.

In the URL Buffer Size area, check the

Enable buffering

check box.

Enter the number of 1550-byte buffers. Valid values range from 1 to 128.

Click

OK


Caching Server Addresses

After you access a website, the filtering server can allow the adaptive security appliance to cache the server address for a certain period of time, as long as each website hosted at the address is in a category that is permitted at all times. When you access the server again, or if another user accesses the server, the adaptive security appliance does not need to consult the filtering server again.

Note

Requests for cached IP addresses are not passed to the filtering server and are not logged. As a result, this activity does not appear in any reports. You can accumulate Websense run logs before using the

url-cache

command.

To improve throughput, perform the following steps:

Step 1

Step 2

Step 3

Step 4


Advanced


In the URL Cache Size area, check the

Enable caching based on

check box to enable caching according to the specified criteria.


•

•

Destination Address—This option caches entries according to the URL destination address. Choose this setting if all users share the same URL filtering policy on the Websense server.

Source/Destination Address—This option caches entries according to both the source address that initiates the URL request and the URL destination address. Choose this setting if users do not share the same URL filtering policy on the server.

Enter the cache size within the range from 1 to 128 (KB).

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Step 5

Click

OK


Filtering HTTP URLs

This section describes how to configure HTTP filtering with an external filtering server and includes the following topics:

•

Enabling Filtering of Long HTTP URLs, page 34-6

Enabling Filtering of Long HTTP URLs

By default, the adaptive security appliance considers an HTTP URL to be a long URL if it is greater than

1159 characters. You can increase the maximum length allowed.

To configure the maximum size of a single URL, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5


Advanced


In the Long URL Support area, check the

Use Long URL

check box to enable long URLs for filtering servers.

Enter the maximum URL length allowed, up to a maximum of 4 KB.

Enter the memory allocated for long URLs in KB.

Click

OK


Configuring Filtering Rules

Before you can add an HTTP, HTTPS, or FTP filter rule, you must enable a URL filtering server. To enable a URL filtering server, choose

Configuration > Firewall > URL Filtering Servers

.

To configure filtering rules, perform the following steps:

Step 1

Step 2

Step 3

From the ASDM main window, choose

Configuration > Firewall > Filter Rules

.

In the toolbar, click

Add

to display the types of filter rules that are available to add from the following list:

•

Add Filter ActiveX Rule

•

•

•

Add Filter Java Rule

Add Filter HTTP Rule

Add Filter HTTPS Rule

Add Filter FTP Rule

•

If you chose Add Filter ActiveX Rule, specify the following settings:

•


Filter ActiveX

or

Do not filter ActiveX

.

•

Enter the source of the traffic to which the filtering action applies. To enter the source, choose from the following options:

–

Enter

any

to indicate any source address.


34-6 OL-20339-01



Step 4

•

–

–

–

Enter a hostname.

Enter an IP address and optional network mask. You can express the netmask in CIDR or dotted decimal notation. For example, you can enter

10.1.1.0/24

or

10.1.1.0/255.255.255.0

.

Click the ellipses to display the Browse Source dialog box. Choose a host or address from the drop-down list.

Enter the destination of the traffic to which the filtering action applies. To enter the source, choose from the following options:

–

Enter

any

to indicate any destination address.

–

–

Enter a hostname.


10.1.1.0/24

or

10.1.1.0/255.255.255.0

.

•

–

•

–

Click the ellipses to display the Browse Service dialog box. Choose a service from the drop-down list.

Click

OK


•

•

Click

Apply


If you chose Add Filter Java Rule, specify the following settings:

•


Filter Java

or

Do not filter Java

.


–

<—Less than. For example, <tcp/2000.

>—Greater than. For example, >tcp/2000.

- —Range. For example, tcp/2000-3000.

Enter a well-known service name, such as HTTP or FTP.

–

–

–

Enter

any


Enter a hostname.


10.1.1.0/24

or

10.1.1.0/255.255.255.0

.


•

–

Click the ellipses to display the Browse Destination dialog box. Choose a host or address from the drop-down list.

Identify the service of the traffic to which the filtering action applies. To identify the service, enter one of the following:

–

tcp/

port

—The port number can range from 1 to 65535. Additionally, you can use the following modifiers with the TCP service:

!=—Not equal to. For example, !=tcp/443.


–

Enter

any


–

Enter a hostname.

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34-7



Step 5

•

–


10.1.1.0/24

or

10.1.1.0/255.255.255.0

.

–



–

tcp/

port

—The port number can be from 1 to 65535. Additionally, you can use the following modifiers with the TCP service:


–





•

–


Click

OK


•

•

Click

Apply


If you chose Add Filter HTTP Rule, specify the following settings:

•


Filter HTTP

or

Do not filter HTTP

.


•

•

–

–

Enter

any


Enter a hostname.

–

–


10.1.1.0/24

or

10.1.1.0/255.255.255.0

.



–

Enter

any


–

–

Enter a hostname.


10.1.1.0/24

or

10.1.1.0/255.255.255.0

.

–



–

tcp/

port




34-8


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OL-20339-01

Step 6

•

•

•

–




–


Choose the action to take when the URL exceeds the specified size from the drop-down list.

Check the

Allow outbound traffic if URL server is not available

check box to connect without

URL filtering being performed. When this check box is unchecked, you cannot connect to Internet websites if the URL server is unavailable.

Check the

Block users from connecting to an HTTP proxy server

check box to prevent HTTP requests made through a proxy server.

•

•

Check the

Truncate CGI parameters from URL sent to URL server

check box to have the adaptive security appliance forward only the CGI script location and the script name, without any parameters, to the filtering server.

Click

OK


•

•

Click

Apply


If you chose Add Filter HTTPS Rule, specify the following settings:

•


Filter HTTPS

or

Do not filter HTTPS

.


–

–

–

–

Enter

any


Enter a hostname.


10.1.1.0/24

or

10.1.1.0/255.255.255.0

.


•

•


–

Enter

any


–

–

Enter a hostname.


10.1.1.0/24

or

10.1.1.0/255.255.255.0

.

–



–

tcp/

port


!=—Not equal to. For example, !=tcp/443





34-9



Step 7

•

–


–


Check the




•

•

If you chose Add Filter FTP Rule, specify the following settings:

•


Filter FTP

or

Do not filter FTP

.

•

Click

OK


Click

Apply



–

Enter

any


–

–

Enter a hostname.


10.1.1.0/24

or

10.1.1.0/255.255.255.0

.

•

–



–

–

Enter

any


Enter a hostname.

–

–


10.1.1.0/24

or

10.1.1.0/255.255.255.0

.


•

•

•


–

tcp/

port


!=—Not equal to. For example, !=tcp/443




–

–

Enter a well-known service name, such as http or ftp.


Check the




Check the

Block interactive FTP sessions (block if absolute FTP path is not provided)

check box to drop FTP requests if they use a relative path name to the FTP directory.

34-10


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Step 8

Step 9

Step 10

•

Click

OK


•

Click

Apply


To modify a filtering rule, select it and click

Edit

to display the Edit Filter Rule dialog box for the specified filtering rule.

Make the required changes, then click

OK


Click

Apply


Filtering the Rule Table

To find a specific rule if your rule table includes a lot of entries, you can apply a filter to the rule table to show only the rules specified by the filter. To filter the rule table, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Click

Find

on the toolbar to display the Filter toolbar.

Choose the type of filter from the Filter drop-down list:

•

•

•

Source—Displays rules based on the specified source address or hostname.

Destination—Displays rules based on the specified destination address or hostname.

•

•

Source or Destination—Displays rules based on the specified source or destination address or hostname.

Service—Displays rules based on the specified service.

•

Rule Type—Displays rules based on the specified rule type.

Query—Displays rules based on a complex query composed of source, destination, service, and rule type information.

For Source, Destination, Source or Destination, and Service filters, perform the following steps:

a.

Enter the string to match using one of the following methods:

–

–

Type the source, destination, or service name in the adjacent field.

Click the ellipses to open a Browse dialog box from which you can choose existing services, IP addresses, or host names.

b.

Choose the match criteria from the drop-down list. Choose

is

for exact string matches or

contains

for partial string matches.

For Rule Type filters, choose the rule type from the list.

For Query filters, click

Define Query

. To define queries, see the

“Defining Queries” section on page 34-12

.

To apply the filter to the rule table, click

Filter

.

To remove the filter from the rule table and display all rule entries, click

Clear

.

To show the packet trace for the selected rule, click

Packet Trace

.

To show and hide the selected rule diagram, click

Diagram

.

To remove a filter rule and place it elsewhere, click

Cut

.

To copy a filter rule, click

Copy

. Then to move the copied filter rule elsewhere, click

Paste

.

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34-11



Step 12

To delete a selected filter rule, click

Delete

.

Defining Queries

To define queries, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Enter the IP address or hostname of the source. Choose

is

for an exact match or choose

contains

for a partial match. Click the ellipses to display the Browse Source dialog box. You can specify a network mask using CIDR notation (address/bit-count). You can specify multiple addresses by separating them with commas.

Enter the IP address or hostname of the destination. Choose

is


contains

for a partial match. Click the ellipses to display the Browse Destination dialog box. You can specify a network mask using CIDR notation (address/bit-count). You can specify multiple addresses by separating them with commas.

Enter the IP address or hostname of the source or destination. Choose

is


contains

for a partial match. Click the ellipses to display the Browse Source dialog box. You can specify a network mask using CIDR notation (address/bit-count). You can specify multiple addresses by separating them with commas.

Enter the protocol, port, or name of a service. Choose

is


contains

for a partial match. Click the ellipses to display the Browse Service dialog box. You can specify a network mask using CIDR notation (address/bit-count). You can specify multiple addresses by separating them with commas.

Choose the rule type from the drop-down list.

Click

OK


After you click

OK

, the filter is immediately applied to the rule table. To remove the filter, click

Clear

.

Feature History for URL Filtering

Table 34-2 lists the release history for URL filtering. ASDM is backwards-compatible with multiple

platform releases, so the specific ASDM release in which support was added is not listed.

Table 34-2

Feature Name

URL filtering

Feature History for URL Filtering

Platform

Releases

7.0(1)


Filters URLs based on an established set of filtering criteria.

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C H A P T E R

35

Configuring Digital Certificates

This chapter describes how to configure digital certificates and includes the following sections:

•

Information About Digital Certificates, page 35-1

•

•

•

•

•

•

•

•

•

Licensing Requirements for Digital Certificates, page 35-8

Configuring CA Certificate Authentication, page 35-9

Configuring Identity Certificates Authentication, page 35-14

Configuring Code Signer Certificates, page 35-20

Authenticating Using the Local CA, page 35-22

Managing the User Database, page 35-25

Managing User Certificates, page 35-28

Monitoring CRLs, page 35-28

Feature History for Certificate Management, page 35-29

Information About Digital Certificates

Digital certificates provide digital identification for authentication. A digital certificate includes information that identifies a device or user, such as the name, serial number, company, department, or IP address. CAs are trusted authorities that “sign” certificates to verify their authenticity, thereby guaranteeing the identity of the device or user. CAs issue digital certificates in the context of a PKI, which uses public-key or private-key encryption to ensure security.

For authentication using digital certificates, at least one identity certificate and its issuing CA certificate must exist on an adaptive security appliance. This configuration allows multiple identities, roots, and certificate hierarchies. Descriptions of several different types of available digital certificates follow:

•

•

A

CA certificate

is used to sign other certificates. It is self-signed and called a

root certificate

. A certificate that is issued by another CA certificate is called a

subordinate certificate

. For more information, see the

“Configuring CA Certificate Authentication” section on page 35-9

.

CAs also issue

identity certificates

, which are certificates for specific systems or hosts. For more information, see the

“Configuring Identity Certificates Authentication” section on page 35-14 .

•

Code-signer certificates

are special certificates that are used to create digital signatures to sign code, with the signed code itself revealing the certificate origin. For more information, see the

“Configuring Code Signer Certificates” section on page 35-20 .


35-1 OL-20339-01

Chapter 35 Configuring Digital Certificates


The local CA integrates an independent certificate authority feature on the adaptive security appliance, deploys certificates, and provides secure revocation checking of issued certificates. The local CA provides a secure, configurable, in-house authority for certificate authentication with user enrollment through a website login page. For more information, see the

“Authenticating Using the Local CA” section on page 35-22 , the

“Managing User Certificates” section on page 35-28

, and the

“Managing the

User Database” section on page 35-25 .

Note

CA certificates and identity certificates apply to both site-to-site VPN connections and remote access

VPN connections. Procedures in this document refer to remote access VPN use in the ASDM GUI.

CAs are responsible for managing certificate requests and issuing digital certificates. A digital certificate includes information that identifies a user or device, such as a name, serial number, company, department, or IP address. A digital certificate also includes a copy of the public key for the user or device. A CA can be a trusted third party, such as VeriSign, or a private (in-house) CA that you establish within your organization.


•

Public Key Cryptography, page 35-2

•

•

•

Certificate Scalability, page 35-3

Key Pairs, page 35-3

Trustpoints, page 35-4

•

•

•

•

Revocation Checking, page 35-4

CRLs, page 35-4

OCSP, page 35-5

•

•

•

The Local CA Server, page 35-6

Supported CA Servers, page 35-7

Certificate Enrollment, page 35-7

Storage for Local CA Files, page 35-8

Public Key Cryptography

Digital signatures, enabled by public key cryptography, provide a way to authenticate devices and users.

In public key cryptography, such as the RSA encryption system, each user has a key pair containing both a public and a private key. The keys act as complements, and anything encrypted with one of the keys can be decrypted with the other.

In simple terms, a signature is formed when data is encrypted with a private key. The signature is attached to the data and sent to the receiver. The receiver applies the public key of the sender to the data.

If the signature sent with the data matches the result of applying the public key to the data, the validity of the message is established.

This process relies on the receiver having a copy of the public key of the sender and a high degree of certainty that this key belongs to the sender, not to someone pretending to be the sender.

Obtaining the public key of a sender is normally handled externally or through an operation performed at installation. For example, most web browsers are configured with the root certificates of several CAs by default. For VPN, the IKE protocol, a component of IPSec, can use digital signatures to authenticate peer devices before setting up security associations.

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Certificate Scalability

Without digital certificates, you must manually configure each IPSec peer for each peer with which it communicates; as a result, each new peer that you add to a network would require a configuration change on each peer with which it needs to communicate securely.

When you use digital certificates, each peer is enrolled with a CA. When two peers try to communicate, they exchange certificates and digitally sign data to authenticate each other. When a new peer is added to the network, you enroll that peer with a CA and none of the other peers need modification. When the new peer attempts an IPSec connection, certificates are automatically exchanged and the peer can be authenticated.

With a CA, a peer authenticates itself to the remote peer by sending a certificate to the remote peer and performing some public key cryptography. Each peer sends its unique certificate, which was issued by the CA. This process works because each certificate encapsulates the public key for the associated peer, each certificate is authenticated by the CA, and all participating peers recognize the CA as an authenticating authority. The process is called IKE with an RSA signature.

The peer can continue sending its certificate for multiple IPSec sessions, and to multiple IPSec peers, until the certificate expires. When its certificate expires, the peer administrator must obtain a new one from the CA.

CAs can also revoke certificates for peers that no longer participate in IPSec. Revoked certificates are not recognized as valid by other peers. Revoked certificates are listed in a CRL, which each peer may check before accepting a certificate from another peer.

Some CAs have an RA as part of their implementation. An RA is a server that acts as a proxy for the

CA, so that CA functions can continue when the CA is unavailable.

Key Pairs

Key pairs are RSA keys, which have the following characteristics:

•

RSA keys can be used for SSH or SSL.

•

•

SCEP enrollment supports the certification of RSA keys.

For the purposes of generating keys, the maximum key modulus for RSA keys is 2048 bits. The default size is 1024. Many SSL connections using identity certificates with RSA key pairs that exceed 1024 bits can cause a high CPU usage on the adaptive security appliance and rejected clientless logins.

•

•

For signature operations, the supported maximum key size is 4096 bits.

You can generate a general purpose RSA key pair, used for both signing and encryption, or you can generate separate RSA key pairs for each purpose. Separate signing and encryption keys help to reduce exposure of the keys, because SSL uses a key for encryption but not signing. However, IKE uses a key for signing but not encryption. By using separate keys for each, exposure of the keys is minimized.

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Trustpoints

Trustpoints let you manage and track CAs and certificates. A trustpoint is a representation of a CA or identity pair. A trustpoint includes the identity of the CA, CA-specific configuration parameters, and an association with one, enrolled identity certificate.

After you have defined a trustpoint, you can reference it by name in commands requiring that you specify a CA. You can configure many trustpoints.

Note

If an adaptive security appliance has multiple trustpoints that share the same CA, only one of these trustpoints sharing the CA can be used to validate user certificates. To control which trustpoint sharing a CA is used for validation of user certificates issued by that CA, use the

support-user-cert-validation

command.

For automatic enrollment, a trustpoint must be configured with an enrollment URL, and the CA that the trustpoint represents must be available on the network and must support SCEP.

You can export and import the keypair and issued certificates associated with a trustpoint in PKCS12 format. This format is useful to manually duplicate a trustpoint configuration on a different adaptive security appliance.

Revocation Checking

When a certificate is issued, it is valid for a fixed period of time. Sometimes a CA revokes a certificate before this time period expires; for example, because of security concerns or a change of name or association. CAs periodically issue a signed list of revoked certificates. Enabling revocation checking forces the adaptive security appliance to check that the CA has not revoked a certificate each time that it uses the certificate for authentication.

When you enable revocation checking, the adaptive security appliance checks certificate revocation status during the PKI certificate validation process, which can use either CRL checking, or OCSP, or both. OCSP is

only

used when the first method returns an error (for example, that the server is unavailable).

With CRL checking, the adaptive security appliance retrieves, parses, and caches CRLs, which provide a complete list of revoked certificates. OCSP offers a more scalable method of checking revocation status in that it localizes certificate status through a validation authority, which it queries for status of a specific certificate.

CRLs

CRLs provide the adaptive security appliance with one way of determining whether a certificate that is within its valid time range has been revoked by the issuing CA. CRL configuration is part of configuration of a trustpoint.

You can configure the adaptive security appliance to make CRL checks mandatory when authenticating a certificate by using the

revocation-check crl

command. You can also make the CRL check optional by using the

revocation-check crl none

command, which allows the certificate authentication to succeed when the CA is unavailable to provide updated CRL data.

The adaptive security appliance can retrieve CRLs from CAs using HTTP, SCEP, or LDAP. CRLs retrieved for each trustpoint are cached for a configurable amount of time for each trustpoint.

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When the adaptive security appliance has cached a CRL for longer than the amount of time it is configured to cache CRLs, the adaptive security appliance considers the CRL too old to be reliable, or

“stale.” The adaptive security appliance tries to retrieve a newer version of the CRL the next time that a certificate authentication requires a check of the stale CRL.

The adaptive security appliance caches CRLs for an amount of time determined by the following two factors:

•

The number of minutes specified with the

cache-time

command. The default value is 60 minutes.

•

The NextUpdate field in the CRLs retrieved, which may be absent from CRLs. You control whether the adaptive security appliance requires and uses the NextUpdate field with the

enforcenextupdate

command.

The adaptive security appliance uses these two factors in the following ways:

•

•

If the NextUpdate field is not required, the adaptive security appliance marks CRLs as stale after the length of time defined by the

cache-time

command.

If the NextUpdate field is required, the adaptive security appliance marks CRLs as stale at the sooner of the two times specified by the

cache-time

command and the NextUpdate field. For example, if the

cache-time

command is set to 100 minutes and the NextUpdate field specifies that the next update is 70 minutes away, the adaptive security appliance marks CRLs as stale in 70 minutes.

If the adaptive security appliance has insufficient memory to store all CRLs cached for a given trustpoint, it deletes the least recently used CRL to make room for a newly retrieved CRL.

OCSP

OCSP provides the adaptive security appliance with a way of determining whether a certificate that is within its valid time range has been revoked by the issuing CA. OCSP configuration is part of trustpoint configuration.

OCSP localizes certificate status on a validation authority (an OCSP server, also called the

responder

) which the adaptive security appliance queries for the status of a specific certificate. This method provides better scalability and more up-to-date revocation status than does CRL checking, and helps organizations with large PKI installations deploy and expand secure networks.

Note

The adaptive security appliance allows a five-second time skew for OCSP responses.

You can configure the adaptive security appliance to make OCSP checks mandatory when authenticating a certificate by using the

revocation-check ocsp

command. You can also make the OCSP check optional by using the

revocation-check ocsp none

command, which allows the certificate authentication to succeed when the validation authority is unavailable to provide updated OCSP data.

OCSP provides three ways to define the OCSP server URL. The adaptive security appliance uses these servers in the following order:

1.

2.

3.

The OCSP URL defined in a match certificate override rule by using the

match certificate

command).

The OCSP URL configured by using the

ocsp url

command.

The AIA field of the client certificate.

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35-5



Note

To configure a trustpoint to validate a self-signed OCSP responder certificate, you import the self-signed responder certificate into its own trustpoint as a trusted CA certificate. Then you configure the

match certificate

command in the client certificate validating trustpoint to use the trustpoint that includes the self-signed OCSP responder certificate to validate the responder certificate. Use the same procedure for configuring validating responder certificates external to the validation path of the client certificate.

The OCSP server (responder) certificate usually signs the OCSP response. After receiving the response, the adaptive security appliance tries to verify the responder certificate. The CA normally sets the lifetime of the OCSP responder certificate to a relatively short period to minimize the chance of being compromised.The CA usually also includes an ocsp-no-check extension in the responder certificate, which indicates that this certificate does not need revocation status checking. However, if this extension is not present, the adaptive security appliance tries to check revocation status using the same method specified in the trustpoint. If the responder certificate is not verifiable, revocation checks fail. To avoid this possibility, use the

revocation-check none

command to configure the responder certificate validating trustpoint, and use the r

evocation-check ocsp

command to configure the client certificate.

The Local CA Server

The local CA performs the following tasks:

•

•

•

Integrates basic certificate authority operation on the adaptive security appliance.

Deploys certificates.

•

•

Provides secure revocation checking of issued certificates.

Provides a certificate authority on the adaptive security appliance for use with browser-based and client-based SSL VPN connections.

Provides trusted digital certificates to users, without the need to rely on external certificate authorization.

•

Provides a secure, in-house authority for certificate authentication and offers straightforward user enrollment by means of a website login.

After you configure a local CA server on the adaptive security appliance, users can enroll for a certificate by logging into a website and entering a username and a one-time password that is provided by the local

CA administrator to validate their eligibility for enrollment.

As shown in Figure 35-1

, the local CA server resides on the adaptive security appliance and handles enrollment requests from website users and CRL inquiries coming from other certificate validating devices and adaptive security appliances. Local CA database and configuration files are maintained either on the adaptive security appliance flash memory (default storage) or on a separate storage device.

35-6


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Figure 35-1 The Local CA

User Enrollment Webpage for PKCS12 Users Certificate

Enrollment and Retrieval

ASDM and CLI configuration and management

Security Device with Local CA

Configured

HTTP CRL retrieval

Local Database in flash memory or Mounted external file system

(CIFS or FTP)

Supported CA Servers

The adaptive security appliance supports the following CA servers:

•

•

•

•

•

•

•

Cisco IOS CS

Baltimore Technologies

Entrust

Microsoft Certificate Services

Netscape CMS

RSA Keon

VeriSign

Certificate Enrollment

The adaptive security appliance needs a CA certificate for each trustpoint and one or two certificates for itself, depending upon the configuration of the keys used by the trustpoint. If the trustpoint uses separate

RSA keys for signing and encryption, the adaptive security appliance needs two certificates, one for each purpose. In other key configurations, only one certificate is needed.

The adaptive security appliance supports enrollment with SCEP and with manual enrollment, which lets you paste a base-64-encoded certificate directly into the terminal. For site-to-site VPNs, you must enroll each adaptive security appliance. For remote access VPNs, you must enroll each adaptive security appliance and each remote access VPN client.

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35-7


Licensing Requirements for Digital Certificates

Storage for Local CA Files

The adaptive security appliance accesses and implements user information, issued certificates, and revocation lists using a local CA database. This database resides in local flash memory by default, or can be configured to reside on an external file system that is mounted and accessible to the adaptive security appliance.

No limits exist on the number of users that can be stored in the local CA user database; however, if flash memory storage issues arise, syslogs are generated to alert the administrator to take action, and the local

CA could be disabled until the storage issues are resolved. Flash memory can store a database with 3500 users or less; however, a database of more than 3500 users requires external storage.

Licensing Requirements for Digital Certificates


Model

All models


Base License.








Does not support replicating sessions in Stateful Failover.

IPv6 Guidelines

Supports IPv6.


For adaptive security appliances that are configured as CA servers or clients, limit the validity period of the certificate to less than the recommended end date of 03:14:08 UTC, January 19, 2038. This guideline also applies to imported certificates from third-party vendors.

35-8


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Configuring CA Certificate Authentication


The CA Certificates pane displays the available certificates, identified by the issued to and issued by CA server, the date that the certificate expires, the associated trustpoints, and the certificate usage or purpose. In the CA Certificates pane, you can perform the following tasks:

•

Authenticate self-signed or subordinate CA certificates.

•

•

•

Install CA certificates on the adaptive security appliance.

Create a new certificate configuration.

Edit an existing certificate configuration.

Obtain a CA certificate manually and import it.

•

•

•

•

Have the adaptive security appliance use SCEP to contact the CA, and then automatically obtain and install the certificate.

Display details and issuer information for a selected certificate.

•

•

Access the CRL for an existing CA certificate.

Remove the configuration of an existing CA certificate.

Save the new or modified CA certificate configuration.

Discard any changes and return the certificate configuration to the original settings.

•


•

Adding or Installing a CA Certificate, page 35-9

•

•

•

•

•

•

•

Editing or Removing a CA Certificate Configuration, page 35-10

Showing CA Certificate Details, page 35-11

Requesting a CRL, page 35-11

Configuring CRL Retrieval Policy, page 35-11

Configuring CRL Retrieval Methods, page 35-12

Configuring OCSP Rules, page 35-13

Configuring Advanced CRL and OCSP Settings, page 35-13

Adding or Installing a CA Certificate

You can add a new certificate configuration from an existing file, by manually pasting a certificate in

PEM format, or by automatic enrollment using SCEP. SCEP is a secure messaging protocol that requires minimal user intervention and lets you enroll and install certificates using only the VPN Concentrator

Manager.

To add or install a CA certificate, perform the following steps:

Step 1

Step 2

Step 3


Configuration > Remote Access VPN > Certificate

Management > CA Certificates

.

Click

Add

.

The Install Certificate dialog box appears. The selected trustpoint name appears in read-only format.

To add a certificate configuration from an existing file, click the

Install from a file

radio button (this is the default setting).


OL-20339-01 35-9



Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Enter the path and file name, or click

Browse

to search for the file. Then click

Install Certificate

.

To enroll manually, click the

Paste certificate in PEM format

radio button.

Copy and paste the PEM format (base64 or hexadecimal) certificate into the area provided, then click


.

To enroll automatically, click the

Use SCEP

radio button. The adaptive security appliance contacts the

CA using SCEP, obtains the certificates, and installs them on the device. To use SCEP, you must enroll with a CA that supports SCEP, and you must enroll via the Internet. Automatic enrollment using SCEP requires that you provide the following information:

•

The path and file name of the certificate to be automatically installed.

•

•

The maximum number of minutes to retry certificate installation.The default is one minute.

The number of retries for installing a certificate. The default is zero, which indicates unlimited retries within the retry period.

To display additional configuration options for new and existing certificates, click

More Options

.

The Configuration Options for CA Certificates pane appears.


“Configuring CA Certificates for Revocation” section on page 35-11 .

Editing or Removing a CA Certificate Configuration

To change or remove an existing CA certificate configuration, perform the following steps:

Step 1

Step 2

To change an existing CA certificate configuration, select it, and then click

Edit

.

The Edit Options for CA Certificates pane appears. To change any of these settings, see the following sections for procedures:

•

“Configuring CRL Retrieval Policy” section on page 35-11

•

•

“Configuring CRL Retrieval Methods” section on page 35-12

“Configuring OCSP Rules” section on page 35-13

•

“Configuring Advanced CRL and OCSP Settings” section on page 35-13

To remove a CA certificate configuration, select it, and then click

Delete

.

Note

After you delete a certificate configuration, it cannot be restored. To recreate the deleted certificate, click

Add

to reenter all of the certificate configuration information.

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Showing CA Certificate Details

To show detailed information about the selected CA certificate, click

Show Details

to display the

Certificate Details dialog box, which includes the following three

display-only

tabs:

•

The General tab displays the values for type, serial number, status, usage, public key type, CRL distribution point, the times within which the certificate is valid, and associated trustpoints. The values apply to both available and pending status.

•

•

The Issued to tab displays the X.500 fields of the subject DN or certificate owner and their values.

The values apply only to available status.

The Issued by tab displays the X.500 fields of the entity granting the certificate. The values apply only to available status.

Requesting a CRL

To update the current version of the CRL, click

Request CRL

. CRL updates provide the current status of certificate users. If the request fails, an error message appears. The CRL is updated and regenerated automatically until it expires; clicking

Request CRL

forces an immediate CRL file update and regeneration.

Configuring CA Certificates for Revocation

To configure CA certificates for revocation, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

In the Configuration Options for CA Certificates pane, click the

Revocation Check

tab.

To disable revocation checking of certificates, click the

Do not check certificates for revocation

radio button.

To select one or more revocation checking methods (CRL or OCSP), click the

Check certificates for revocation

radio button.

In the Revocation Methods area, available methods appear on the left. Click

Add

to move a method to the right and make it available. Click

Move Up

or

Move Down

to change the method order.

The methods you choose are implemented in the order in which you add them. If a method returns an error, the next revocation checking method activates.

Check the

Consider certificate valid if revocation checking returns errors

check box to ignore revocation checking errors during certificate validation.

Click

OK

to close the Revocation Check tab. Alternatively, to continue, see the “Configuring CRL

Retrieval Policy” section on page 35-11

.

Configuring CRL Retrieval Policy

To configure the CRL retrieval policy, perform the following steps:

Step 1


CRL Retrieval Policy

tab.

OL-20339-01


35-11



Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Check the

Use CRL Distribution Point from the certificate

check box to direct revocation checking to the CRL distribution point from the certificate being checked.

Check the

Use Static URLs configured below

check box to list specific URLs to be used for CRL retrieval. The URLs you select are implemented in the order in which you add them. If an error occurs with the specified URL, the next URL in order is taken.

In the Static Configuration area, click

Add

.

The Add Static URL dialog box appears.

In the URL field, enter the static URL to use for distributing the CRLs, and then click

OK

.

The URL that you entered appears in the Static URLs list.

To change the static URL, select it, and then click

Edit

.

To remove an existing static URL, select it, and then click

Delete

.

To change the order in which the static URLs appear, click

Move Up

or

Move Down

.

Click

OK

to close this tab. Alternatively, to continue, see the

“Configuring CRL Retrieval Methods” section on page 35-12 .

Configuring CRL Retrieval Methods

To configure CRL retrieval methods, perform the following steps:

Step 1

Step 2

Step 3


CRL Retrieval Methods

tab.

Choose one of the following three retrieval methods:

•

To enable LDAP for CRL retrieval, check the

Enable Lightweight Directory Access Protocol

(LDAP)

check box. With LDAP, CRL retrieval starts an LDAP session by connecting to a named

LDAP server, accessed by a password. The connection is on TCP port 389 by default. Enter the following required parameters:

–

–

Name

Password

–

–

Confirm Password

Default Server (server name)

•

–

Default Port (389)

To enable HTTP for CRL retrieval, check the

Enable HTTP

check box.

•

To enable SCEP for CRL retrieval, check the

Enable Simple Certificate Enrollment Protocol

(SCEP)

check box.

Click

OK


“Configuring OCSP Rules” section on page 35-13

.

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OL-20339-01



Configuring OCSP Rules

The adaptive security appliance examines OCSP rules in priority order, and applies the first one that matches. X.509 digital certificates are an alternative to using CRLs.

Note

Make sure that you have configured a certificate map before you try to add OCSP rules. If a certificate map has not been configured, an error message appears. To configure a certificate map, choose

Configuration > Network (Client) Access, Advanced > IPSec > Certificate to Connection Profile

Maps > Rules > Add

.

To configure OCSP rules for obtaining revocation status of an X.509 digital certificate, perform the following steps:

Step 4

Step 5

Step 6

Step 7

Step 8

Step 1

Step 2

Step 3

Step 9

Step 10

Step 11


OCSP Rules

tab.

Choose the certificate map to match to this OCSP rule. Certificate maps match user permissions to specific fields in a certificate. The name of the CA that the adaptive security appliance uses to validate responder certificates appears in the Certificate field. The priority number for the rule appears in the

Index field. The URL of the OCSP server for this certificate appears in the URL field.

To add a new OCSP rule, click

Add

.

The Add OCSP Rule dialog box appears.

Choose the certificate map to use from the drop-down list.

Choose the certificate to use from the drop-down list.

Enter the priority number for the rule.

Enter the URL of the OCSP server for this certificate.

When you are done, click

OK


The newly added OCSP rule appears in the list.

To edit an existing OCSP rule, select it, and then click

Edit

.

To delete an OCSP rule, select it, and then click

Delete

.

Click

OK


“Configuring Advanced CRL and OCSP

Settings” section on page 35-13 .

Configuring Advanced CRL and OCSP Settings

When a certificate is issued, it is valid for a fixed period of time. Sometimes a CA revokes a certificate before this time period expires; for example, because of security concerns or a change of name or association. CAs periodically issue a signed list of revoked certificates. Enabling revocation checking forces the adaptive security appliance to check that the CA has not revoked the certificate being verified.

The adaptive security appliance supports two methods of checking revocation status: CRL and OCSP.

To configure additional CRL and OCSP settings, perform the following steps:

Step 1


Advanced

tab.

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Configuring Identity Certificates Authentication

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

In the CRL Options area, enter the number of minutes between cache refreshes. The default is 60 minutes. The range is 1-1440 minutes. To avoid having to retrieve the same CRL from a CA repeatedly, the adaptive security appliance can store retrieved CRLs locally, which is called CRL caching. The CRL cache capacity varies by platform and is cumulative across all contexts. If an attempt to cache a newly retrieved CRL would exceed its storage limits, the adaptive security appliance removes the least recently used CRL until more space becomes available.

Check the

Enforce next CRL update

check box to require valid CRLs to have a Next Update value that has not expired. Uncheck the

Enforce next CRL update

check box to let valid CRLs with no Next

Update value or a Next Update value that has expired.

In the OCSP Options area, enter the URL for the OCSP server. The adaptive security appliance uses

OCSP servers according to the following order:

1.

2.

OCSP URL in a match certificate override rule

OCSP URL configured in the selected OCSP Options attribute

3.

AIA field of a remote user certificate

By default, the

Disable nonce extension

check box is checked, which cryptographically binds requests with responses to avoid replay attacks. This process works by matching the extension in the request to that in the response, ensuring that they are the same. Uncheck the

Disable nonce extension

check box if the OCSP server you are using sends pregenerated responses that do not include this matching nonce extension.

In the Validation Policy area, choose one of the following options:

•

Click the

SSL

radio button or the

IPSec

radio button to restrict the type of remote session that this

CA can be used to validate.

•

Click the

SSL and IPSec

radio button to let the CA validate both types of sessions.

In the Other Options area, choose one of the following options:

•

•

Check the

Accept certificates issued by this CA

check box to indicate that the adaptive security appliance should accept certificates from the specified CA.

Check the

Accept certificates issued by the subordinate CAs of this CA

check box to indicate that the adaptive security appliance should accept certificates from the subordinate CA.

Click

OK

to close this tab, and then click

Apply

to save your configuration changes.

What to Do Next

See the



•

•

•

An identity certificate can be used to authenticate VPN access through the adaptive security appliance.

In the Identity Certificates Authentication pane, you can perform the following tasks:

•

Add or import a new identity certificate.

Display details of an identity certificate.

Delete an existing identity certificate.

Export an existing identity certificate.

35-14


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•

•

Install an existing identity certificate.

•

Enroll for an identity certificate with Entrust.


•

•

•

•

•

Adding or Importing an Identity Certificate, page 35-15

Showing Identity Certificate Details, page 35-17

Deleting an Identity Certificate, page 35-17

Exporting an Identity Certificate, page 35-17

Generating a Certificate Signing Request, page 35-18

Installing Identity Certificates, page 35-19


Adding or Importing an Identity Certificate

To add or import a new identity certificate configuration, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Step 12



Management > Identity Certificates

.

Click

Add

.

The Add Identity Certificate dialog box appears, with the selected trustpoint name displayed at the top.

To import an identity certificate from an existing file, click the

Import the identity certificate from a file

radio button.

Enter the passphrase used to decrypt the PKCS12 file.

Enter the path name of the file, or click

Browse

to display the Import ID Certificate File dialog box. Find the certificate file, and then click

Import ID Certificate File

.

To add a new identity certificate, click the

Add a new identity certificate

radio button.

Click

New

to display the Add Key Pair dialog box.

To use the default key pair name, click the

Use default keypair name

radio button.

To use a new key pair name, click the

Enter a new key pair name

radio button, and type the new name.

The adaptive security appliance supports multiple key pairs.

Choose the modulus size from the drop-down list.

Choose the key pair usage by clicking the

General purpose

radio button (default) or

Special

radio button. When you choose the

Special

radio button, the adaptive security appliance generates two key pairs, one for signature use and one for encryption use. This selection indicates that two certificates are required for the corresponding identity.

Click

Generate Now

to create new key pairs, and then click

Show

to display the Key Pair Details dialog box, which includes the following

display-only

information:

•

The name of the key pair whose public key is to be certified.

•

•

•

•

The time of day and the date when the key pair is generated.

The usage of an RSA key pair.

The modulus size (bits) of the key pairs: 512, 768, 1024, and 2048. The default is 1024.

The key data, which includes the specific key data in text format.

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Step 13

Step 14

Step 15

Step 16

Step 17

Step 18

Step 19

Click

OK

when you are done to close the Key Pair Details dialog box.

Choose a certificate subject DN to form the DN in the identity certificate. and then click

Select

to display the Certificate Subject DN dialog box.

Choose one or more DN attributes that you want to add from the drop-down list, enter a value, and then click

Add

. Available X.500 attributes for the Certificate Subject DN are the following:

•

•

•

Common Name (CN)

Department (OU)

Company Name (O)

Country (C)

•

•

•

State/Province (ST)

Location (L)

•

E-mail Address (EA)

Click

OK

when you are done to close the Certificate Subject DN dialog box.

To create self-signed certificates, check the

Generate self-signed certificate

check box.

To have the identity certificate act as the local CA, check the

Act as local certificate authority and issue dynamic certificates to TLS proxy

check box.

To establish additional identity certificate settings, click

Advanced

.

The Advanced Options dialog box appears, with the following three tabs: Certificate Parameters,

Enrollment Mode, and SCEP Challenge Password.

Note

Enrollment mode settings and the SCEP challenge password are not available for self-signed certificates.

Step 20

Step 21

Step 22

Click the

Certificate Parameters

tab, and then enter the following information:

•

•

•

The FQDN, an unambiguous domain name, to indicate the position of the node in the DNS tree hierarchy.

The e-mail address associated with the identity certificate.

The adaptive security appliance IP address on the network in four-part, dotted-decimal notation.

•

Click the

Enrollment Mode


•

Choose the enrollment method by clicking the

Request by manual enrollment

radio button or the

Request from a CA

radio button.

•

To add the adaptive security appliance serial number to the certificate parameters, check the

Include serial number of the device

check box.

•

The enrollment URL of the certificate to be automatically installed through SCEP.

The maximum number of minutes allowed to retry installing an identity certificate. The default is one minute.

•

The maximum number of retries allowed for installing an identity certificate. The default is zero, which indicates an unlimited number of retries within the retry period.

Click the

SCEP Challenge Password


•

•

The SCEP password

The SCEP password confirmation

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Step 23

Step 24

Step 25

Click

OK

when you are done to close the Advanced Options dialog box.

Click

Add Certificate

in the Add Identity Certificate dialog box.

The new identity certificate appears in the Identity Certificates list.

Click

Apply

to save the new identity certificate configuration.

Showing Identity Certificate Details

To show detailed information about the selected identity certificate, click

Show Details

to display the


display-only

tabs:

•

•




•


Deleting an Identity Certificate

To remove an identity certificate configuration, select it, and then click

Delete

.

Note


Add


Exporting an Identity Certificate

You can export a certificate configuration with all associated keys and certificates in PKCS12 format, which is the public key cryptography standard, and can be base64 encoded or in hexadecimal format. A complete configuration includes the entire chain (root CA certificate, identity certificate, key pair) but not enrollment settings (subject name, FQDN and so on). This feature is commonly used in a failover or load-balancing configuration to replicate certificates across a group of adaptive security appliances; for example, remote access clients calling in to a central organization that has several units to service the calls. These units must have equivalent certificate configurations. In this case, an administrator can export a certificate configuration and then import it across the group of adaptive security appliances.

To export an identity certificate, perform the following steps:

Step 1

Step 2

Step 3

Click

Export

to display the Export Certificate dialog box.

Enter the name of the PKCS12 format file to use in exporting the certificate configuration. Alternatively, click

Browse

to display the Export ID Certificate File dialog box to find the file to which you want to export the certificate configuration.

Choose the certificate format by clicking the

PKCS12 Format

radio button or the

PEM Format

radio button.

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Step 4

Step 5

Step 6

Enter the passphrase used to encrypt the PKCS12 file for export.

Confirm the encryption passphrase.

Click

Export Certificate

to export the certificate configuration.

An information dialog box appears, informing you that the certificate configuration file has been successfully exported to the location that you specified.

Generating a Certificate Signing Request

Note

Entrust supports a key modulus size of 1024

only

. Consult Entrust if you are using any other value.

To generate a certificate signing request to send to Entrust, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Click

Enroll ASA SSL VPN with Entrust

to display the Generate Certificate Signing Request dialog box.

In the Key Pair area, perform the following steps:

a.

Choose one of the configured key pairs from the drop-down list.

b.

c.

d.

Click

Show

to display the Key Details dialog box, which provides information about the selected key pair, including date and time generated, usage (general or special purpose), modulus size, and key data.

Click

OK

when you are done to close Key Details dialog box.

Click

New

to display the Add Key Pair dialog box. To continue, go to Step 8 of the

“Adding or

Importing an Identity Certificate” section on page 35-15 . When you generate the key pair, you can

send it to the adaptive security appliance or save it to a file.

In the Certificate Subject DN area, enter the following information:

a.

The FQDN or IP address of the adaptive security appliance.

b.

The name of the company.

c.

In the Optional Parameters area, perform the following steps:

a.

Click

Select

to display the Additional DN Attributes dialog box.

b.

c.

d.

e.

The two-letter country code.

Choose the attribute to add from the drop-down list, and then enter a value.

Click

Add

to add each attribute to the attribute table.

Click

Delete

to remove an attribute from the attribute table.

Click

OK

when you are done to close the Additional DN Attributes dialog box.

The added attributes appear in the Additional DN Attributes field.

Enter additional fully qualified domain name information if the CA requires it.

Click

Generate Request

to generate the certificate signing request, which you can then send to Entrust, or save to a file and send later.

The Enroll with Entrust dialog box appears, with the CSR displayed.

35-18


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Step 7

Step 8

To complete the enrollment process, click the

request a certificate from Entrust

link by copying and pasting the CSR provided and submitting it through the Entrust web form, provided at http://www.entrust.net/cisco/. Alternatively, to enroll at a later time, save the generated CSR to a file, then click the

enroll with Entrust

link on the Identity Certificates pane to complete the enrollment process.

Entrust issues a certificate after verifying the authenticity of your request. which may take several days.

You then need to install the certificate by selecting the pending request in the Identity Certificate pane and clicking

Install

. Click

Close

to close the Enroll with Entrust dialog box.

Installing Identity Certificates

The Install button on the Identity Certificates pane is dimmed unless an enrollment is pending. Whenever the adaptive security appliance receives a CSR, the Identity Certificates pane displays the pending ID certificate. When you select the pending Identity Certificate, the Install button activates.

When you transmit the pending request to a CA, the CA enrolls it and returns a certificate to the adaptive security appliance. After you have received the certificate, click

Install

and highlight the appropriate identity certificate to complete the operation.

To installing a pending identity certificate, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Step 12

In the Identity Certificates pane, click

Add

to display the Add Identity Certificate dialog box.

In the Add Identity Certificate dialog box, click the

Add a new identity certificate

radio button.

(Optional) Change the key pair or create a new key pair. A key pair is required.

Enter the Certificate Subject DN information, and then click

Select


Specify all of the subject DN attributes required by the CA involved, and then click

OK

to close the

Certificate Subject DN dialog box.

In the Add Identity Certificate dialog box, click

Advanced

to display the Advanced Options dialog box.

To continue, see Steps 17 through 23 of the


In the Add Identity Certificate dialog box, click

Add Certificate

.

The Identity Certificate Request dialog box appears.

Enter the CSR file name of type, text, such as c:\verisign-csr.txt, and then click

OK

.

Send the CSR text file to the CA. Alternatively, you can paste the text file into the CSR enrollment page on the CA website.

When the CA returns the Identity Certificate to you, go to the Identity Certificates pane, select the pending certificate entry, and click

Install

.

The Install Identity Certificate dialog box appears.

Choose one of the following options by clicking the applicable radio button:

•


.

•

Alternatively, click

Browse

to search for the file.

Paste the certificate data in base-64 format

.

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35-19


Configuring Code Signer Certificates

Step 13

Step 14

Paste the copied certificate data into the area provided.

Click


.

Click

Apply

to save the newly installed certificate with the adaptive security appliance configuration.

What to Do Next

See the

“Configuring Code Signer Certificates” section on page 35-20

.


Code signing appends a digital signature to the actual executable code. This digital signature provides enough information to authenticate the signer, and ensure that the code has not been modified after being signed.

Code signer certificates are special certificates whose associated private keys are used to create digital signatures. The certificates used to sign code are obtained from a CA, in which the signed code reveals the certificate origin. You can import code signer certificates on the Code Signer pane, or choose

Configuration > Remote Access VPN > Clientless SSL VPN Access > Advanced > Java Code Signe

r.

In the Code Signer pane, you can perform the following tasks:

•

•

•

•

Display details of a code signer certificate.

Delete an existing code signer certificate.

Import an existing code signer certificate.

Export an existing code signer certificate.

•

Enroll for a code signer certificate with Entrust.


•

•

Showing Code Signer Certificate Details, page 35-20

Deleting a Code Signer Certificate, page 35-21

•

•

Importing a Code Signer Certificate, page 35-21

Exporting a Code Signer Certificate, page 35-21

Showing Code Signer Certificate Details

To show detailed information about the selected identity certificate, click

Show Details

to display the


display-only

tabs:

•


•

•




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OL-20339-01



Deleting a Code Signer Certificate

To remove a code signer certificate configuration, select it, and then click

Delete

.

Note


Import


Importing a Code Signer Certificate

To import a code signer certificate, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

In the Code Signer pane, click

Import

to display the Import Certificate dialog box.

Enter the passphrase used to decrypt the PKCS12-format file.

Enter the name of the file to import, or click

Browse

to display the Import ID Certificate File dialog box and search for the file.

Select the file to import and click

Import ID Certificate File

.

The selected certificate file appears in the Import Certificate dialog box.

Click

Import Certificate

.

The imported certificate appears in the Code Signer pane.

Click

Apply

to save the newly imported code signer certificate configuration.

Exporting a Code Signer Certificate

To export a code signer certificate, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

In the Code Signer pane, click

Export

to display the Export Certificate dialog box.

Enter the name of the PKCS12 format file to use in exporting the certificate configuration.

In the Certificate Format area, to use the public key cryptography standard, which can be base64 encoded or in hexadecimal format, click the

PKCS12 format

radio button. Otherwise, click the

PEM format

radio button.

Click

Browse

to display the

Export ID Certificate File

dialog box to find the file to which you want to export the certificate configuration.

Select the file and click

Export ID Certificate File

.

The selected certificate file appears in the Export Certificate dialog box.

Enter the passphrase used to decrypt the PKCS12 format file for export.

Confirm the decryption passphrase.

Click

Export Certificate

to export the certificate configuration.

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35-21


Authenticating Using the Local CA

What to Do Next

See the

“Authenticating Using the Local CA” section on page 35-22

.


The local CA provides a secure, configurable in-house authority that resides on the adaptive security appliance for certificate authentication to use with browser-based and client-based SSL VPN connections.

Users enroll by logging in to a specified website. The local CA integrates basic certificate authority operations on the adaptive security appliance, deploys certificates, and provides secure revocation checking of issued certificates.

The local CA lets you perform the following tasks:

•

•

•

Configure the local CA server.

Revoke and unrevoke local CA certificates.

Update CRLs.

Add, edit, and delete local CA users.

•


•

Configuring the Local CA Server, page 35-22

•

Deleting the Local CA Server, page 35-25

Configuring the Local CA Server

To configure a local CA server on the adaptive security appliance, perform the following steps:

Step 1

In the CA Server pane, to activate the local CA server, click the

Enable

radio button. The default is disabled. After you enable the local CA server, the adaptive security appliance generates the local CA server certificate, key pair, and necessary database files, and then archives the local CA server certificate and key pair in a PKCS12 file.

Note

Be sure to review all optional settings carefully before you enable the configured local CA. After you enable it, the certificate issuer name and key size server values cannot be changed.

Step 2

The self-signed certificate key usage extension enables key encryption, key signature, CRL signature, and certificate signature.

When you enable the local CA for the first time, you must provide an alphanumeric Enable passphrase, which must have a minimum of seven, alphanumeric characters. The passphrase protects the local CA certificate and the local CA certificate key pair archived in storage, and secures the local CA server from unauthorized or accidental shutdown. The passphrase is required to unlock the PKCS12 archive if the local CA certificate or key pair is lost and must be restored.

Note

The Enable passphrase is required to enable the local CA server. Be sure to keep a record of the

Enable passphrase in a safe location.

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Step 3

Step 4

Step 5

Step 6

Click

Apply

to save the local CA certificate and key pair, so the configuration is not lost if you reboot the adaptive security appliance.

To change or reconfigure the local CA after the local CA has been configured for the first time, you must shut down the local CA server on the adaptive security appliance by clicking the

Disable

radio button.

In this state, the configuration and all associated files remain in storage and enrollment is disabled.

After the configured local CA has been enabled, the following two settings are

display-only

:

•

•

The Issuer Name field, which lists the issuer subject name and domain name, and is formed using the username and the subject-name-default DN setting as cn=FQDN. The local CA server is the entity that grants the certificate. The default certificate name is provided in the format, cn=hostname.domainname.

The CA Server Key Size setting, which is used for the server certificate generated for the local CA server. Key sizes can be 512, 768, 1024, or 2048 bits per key. The default is 1024 bits per key.

From the drop-down list, choose the client key size of the key pair to be generated for each user certificate issued by the local CA server. Key sizes can be 512, 768, 1024, or 2048 bits per key. The default is 1024 bits per key.

Enter the CA certificate lifetime value, which specifies the number of days that the CA server certificate is valid. The default is 3650 days (10 years). Make sure that you limit the validity period of the certificate to less than the recommended end date of 03:14:08 UTC, January 19, 2038.

The local CA server automatically generates a replacement CA certificate 30 days before expiration, which enables the replacement certificate to be exported and imported onto any other devices for local

CA certificate validation of user certificates that have been issued by the local CA after they have expired.

To notify users of the upcoming expiration, the following syslog message appears in the Latest ASDM

Syslog Messages pane:

%ASA-1-717049: Local CA Server certificate is due to expire in

days

days and a replacement certificate is available for export.

Note

When notified of this automatic rollover, the administrator must take action to make sure that the new local CA certificate is imported to all necessary devices before it expires.

Step 7

Step 8

Step 9

Enter the client certificate lifetime value, which specifies the number of days that a user certificate issued by the CA server is valid. The default is 365 days (one year). Make sure that you limit the validity period of the certificate to less than the recommended end date of 03:14:08 UTC, January 19, 2038.

In the SMTP Server & Email Settings area, you set up e-mail access for the local CA server by specifying the following settings:

a.

Enter the SMTP mail server name or IP address. Alternatively, click the ellipses (...) to display the

Browse Server Name/IP Address dialog box, where you can choose the server name or IP address.

Click

OK

when you are done to close the Browse Server Name/IP Address dialog box.

b.

c.

Enter the from address, from which to send e-mail messages to local CA users, in [email protected]

format. Automatic e-mail messages carry one-time passwords to newly enrolled users and issue e-mail messages when certificates need to be renewed or updated.

Enter the subject, which specifies the subject line in all messages that are sent to users by the local

CA server. If you do not specify a subject, the default is “Certificate Enrollment Invitation.”

To configure additional options, click the

More Options

drop-down arrow.

Enter the CRL distribution point, which is the CRL location on the adaptive security appliance. The default location is http://hostname.domain/+CSCOCA+/asa_ca.crl.

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Step 10

To make the CRL available for HTTP download on a given interface and port, choose a publish-CRL interface from the drop-down list. Then enter the port number, which can be any port number from

1-65535. The default port number is TCP port 80.

Note

You cannot rename the CRL; it always has the name, LOCAL-CA-SERVER.crl.

Step 11

Step 12

Step 13

For example, enter the URL, http://10.10.10.100/user8/my_crl_file.

In this case, only the interface with the specified IP address works and when the request comes in, the adaptive security appliance matches the path, /user8/my_crl_file to the configured URL. When the path matches, the adaptive security appliance returns the stored CRL file.

Enter the CRL lifetime in hours that the CRL is valid. The default for the CA certificate is six hours.

The local CA updates and reissues the CRL each time that a user certificate is revoked or unrevoked, but if no revocation changes occur, the CRL is reissued once every CRL lifetime. You can force an immediate CRL update and regeneration by clicking

Request CRL

in the CA Certificates pane.

Enter the database storage location to specify a storage area for the local CA configuration and data files.

The adaptive security appliance accesses and implements user information, issued certificates, and revocation lists using a local CA database. Alternatively, to specify an external file, enter the path name to the external file or click

Browse

to display the Database Storage Location dialog box.

Choose the storage location from the list of folders that appears, and click

OK

.

Note

Flash memory can store a database with 3500 users or less; a database of more than 3500 users requires external storage.

Step 14

Step 15

Enter a default subject (DN string) to append to a username on issued certificates. The permitted DN attributes are provided in the following list:

•

CN (Common Name)

•

•

•

•

SN (Surname)

O (Organization Name)

L (Locality)

C (Country)

•

•

•

•

OU (Organization Unit)

EA (E-mail Address)

ST (State/Province)

T (Title)

Enter the number of hours for which an enrolled user can retrieve a PKCS12 enrollment file to enroll and retrieve a user certificate. The enrollment period is independent of the OTP expiration period. The default is 24 hours.

Note

Certificate enrollment for the local CA is supported

only

for clientless SSL VPN connections.

For this type of connection, communications between the client and the adaptive security appliance is through a web browser that uses standard HTML.

Step 16

Enter the length of time that a one-time password e-mailed to an enrolling user is valid. The default is

72 hours.

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Managing the User Database

Step 17

Step 18

Enter the number of days before expiration reminders are e-mailed to users. The default is 14 days.

Click

Apply

to save the new or modified CA certificate configuration. Alternatively, click

Rese

t to remove any changes and return to the original settings.

Deleting the Local CA Server

To remove the local CA server from the adaptive security appliance, perform the following steps:

Step 1

Step 2

In the CA Server pane, click

Delete Certificate Authority Serve

r.

The Delete Certificate Authority dialog box appears.

To delete the CA server, click

OK

. To retain the CA server, click

Cancel

.

Note

After you delete the local CA server, it cannot be restored or recovered. To recreate the deleted

CA server configuration, you must reenter all of the CA server configuration information.

What to Do Next

See the

“Managing the User Database” section on page 35-25 .


•

•

•

The local CA user database includes user identification information and user status (enrolled, allowed, revoked, and so on). In the Manage User Database pane, you can perform the following tasks:

•

Add a user to the local CA database.

•

•

•

Change existing user identification information.

Remove a user from the local CA database.

Enroll a user.

Update CRLs.

•

•

•

E-mail OTPs to a user.

View or regenerate (replace) an OTP.


•

Adding a Local CA User, page 35-26

•

•

Sending an Initial OTP or Replacing OTPs, page 35-26

Editing a Local CA User, page 35-26

Deleting a Local CA User, page 35-27

Allowing User Enrollment, page 35-27

Viewing or Regenerating an OTP, page 35-27

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35-25



Adding a Local CA User

To add a local CA user, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

To enter a new user into the local CA database, click

Add

to display the Add User dialog box.

Enter a valid username.

Enter an existing valid e-mail address.

Enter the subject (DN string). Alternatively, click

Select


Choose one or more DN attributes that you want to add from the drop-down list, enter a value, and then click

Add


•

Common Name (CN)

•

•

•

Department (OU)

Company Name (O)

Country (C)

State/Province (ST)

•

•

•

Location (L)

E-mail Address (EA)

Click

OK


Check the

Allow enrollment

check box to enroll the user, and then click

Add User

.

The new user appears in the Manage User Database pane.

Sending an Initial OTP or Replacing OTPs

To automatically send an e-mail notice of enrollment permission with a unique OTP and the local CA enrollment URL to the newly added user, click

Email OTP

.

An Information dialog box appears indicating that the OTP was sent to the new user.

To automatically reissue a new OTP and send an e-mail notice with the new password to an existing or new user, click

Replace OTP

.

Editing a Local CA User

To modify information about an existing local CA user in the database, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Select the specific user and click

Edit

to display the Edit User dialog box.

Enter a valid username.

Enter an existing valid e-mail address.

Enter the subject (DN string). Alternatively, click

Select


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Step 5

Step 6

Step 7

Choose one or more DN attributes that you want to change from the drop-down list, enter a value, and then click

Add

or

Delete


•

•

•

•

•

•

Common Name (CN)

Department (OU)

Company Name (O)

Country (C)

State/Province (ST)

Location (L)

•

E-mail Address (EA)

Click

OK


Check the

Allow enrollment

check box to reenroll the user, and then click

Edit User

.

The updated user details appear in the Manage User Database pane.

Deleting a Local CA User

To remove the user from the database and any certificates issued to that user from the local CA database, select the user, and then click

Delete

.

Note

A deleted user cannot be restored. To recreate the deleted user record, click

Add

to reenter all of the user information.

Allowing User Enrollment

To enroll the selected user, click A

llow Enrollment

.

The status of the user changes to “enrolled” in the Manage User Database pane.

Note

If the user is already enrolled, an error message appears.

Viewing or Regenerating an OTP

To view or regenerate the OTP of the selected user, perform the following steps:

Step 1

Step 2

Step 3

Click

View/Regenerate OTP

to display the View & Regenerate OTP dialog box.

The current OTP appears.

After you are done, click

OK

to close the View & Regenerate OTP dialog box.

To regenerate the OTP, click

Regenerate OTP

.

The newly generated OTP appears.

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35-27

Managing User Certificates

Step 4

Click

OK

to close the View & Regenerate OTP dialog box.


What to Do Next

See the

“Managing User Certificates” section on page 35-28 .

Managing User Certificates

To change the certificate status, perform the following steps:

Step 1

Step 2

Step 3

In the Manage User Certificates pane, select specific certificates by username or by certificate serial number.


•

If the user certificate lifetime period runs out, to remove user access, click

Revoke

. The local CA also marks the certificate as revoked in the certificate database, automatically updates the information, and reissues the CRL.

•

To restore access, select a revoked certificate and click

Unrevoke

. The local CA also marks the certificate as unrevoked in the certificate database, automatically updates the certificate information, and reissues an updated CRL.

Click

Apply

when you are done to save your changes.

What to Do Next

See the

“Monitoring CRLs” section on page 35-28

.

Monitoring CRLs

To monitor CRLs, perform the following steps:

Step 1

Step 2

Step 3


Monitoring > Properties > CRL

.

In the CRL area, choose the CA certificate name from the drop-down list.

To display CRL details, click

View CRL

. For example:

CRL Issuer Name:

cn=asa4.cisco.com

LastUpdate: 09:58:34 UTC Nov 11 2009

NextUpdate: 15:58:34 UTC Nov 11 2009

Cached Until: 15:58:34 UTC Nov 11 2009

Retrieved from CRL Distribution Point:

** CDP Not Published - Retrieved via SCEP

Size (bytes): 224

Associated Trustpoints: LOCAL-CA-SERVER

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Feature History for Certificate Management

Step 4

When you are done, click

Clear CRL

to remove the CRL details and choose another CA certificate to view.


Table 35-1

Table 35-1


Feature History for Certificate Management

Feature Name

Certificate Management

Platform

Releases

7.0(1)


Digital certificates (including CA certificates, identity certificates, and code signer certificates) provide digital identification for authentication. A digital certificate includes information that identifies a device or user, such as the name, serial number, company, department, or IP address. CAs are trusted authorities that “sign” certificates to verify their authenticity, thereby guaranteeing the identity of the device or user. CAs issue digital certificates in the context of a PKI, which uses public-key or private-key encryption to ensure security.

The following paths were introduced, based on the type of

VPN connection being used:


Management

Configuration > Site-to-Site VPN > Certificate

Management

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35-30


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35-32


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35-34


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35-36


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35-38


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35-40


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35-44


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35-46


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35-48


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P

A R T

8

Configuring Application Inspection

C H A P T E R

36

Getting Started With Application Layer Protocol

Inspection

This chapter describes how to configure application layer protocol inspection. Inspection engines are required for services that embed IP addressing information in the user data packet or that open secondary channels on dynamically assigned ports. These protocols require the adaptive security appliance to do a

deep packet inspection instead of passing the packet through the fast path (see the “Stateful Inspection

Overview” section on page 1-18

for more information about the fast path). As a result, inspection engines can affect overall throughput. Several common inspection engines are enabled on the adaptive security appliance by default, but you might need to enable others depending on your network.


•

Information about Application Layer Protocol Inspection, page 36-1

•

•

•



Configuring Application Layer Protocol Inspection, page 36-5

Information about Application Layer Protocol Inspection


•

How Inspection Engines Work, page 36-1

•

When to Use Application Protocol Inspection, page 36-2

How Inspection Engines Work

As illustrated in

Figure 36-1 , the adaptive security appliance uses three databases for its basic operation:

•

Access lists—Used for authentication and authorization of connections based on specific networks, hosts, and services (TCP/UDP port numbers).

•

•

Inspections—Contains a static, predefined set of application-level inspection functions.

Connections (XLATE and CONN tables)—Maintains state and other information about each established connection. This information is used by the Adaptive Security Algorithm and cut-through proxy to efficiently forward traffic within established sessions.


36-1 OL-20339-01

Chapter 36 Getting Started With Application Layer Protocol Inspection

Information about Application Layer Protocol Inspection

Figure 36-1 How Inspection Engines Work

ACL

2

Client

1

7

ASA

6

5

Server

3 4

XLATE

CONN

Inspection

In

Figure 36-1

, operations are numbered in the order they occur, and are described as follows:

1.

2.

A TCP SYN packet arrives at the adaptive security appliance to establish a new connection.

The adaptive security appliance checks the access list database to determine if the connection is permitted.

3.

4.

5.

The adaptive security appliance creates a new entry in the connection database (XLATE and CONN tables).

The adaptive security appliance checks the Inspections database to determine if the connection requires application-level inspection.

After the application inspection engine completes any required operations for the packet, the adaptive security appliance forwards the packet to the destination system.

The destination system responds to the initial request.

6.

7.

The adaptive security appliance receives the reply packet, looks up the connection in the connection database, and forwards the packet because it belongs to an established session.

The default configuration of the adaptive security appliance includes a set of application inspection entries that associate supported protocols with specific TCP or UDP port numbers and that identify any special handling required.

When to Use Application Protocol Inspection

When a user establishes a connection, the adaptive security appliance checks the packet against access lists, creates an address translation, and creates an entry for the session in the fast path, so that further packets can bypass time-consuming checks. However, the fast path relies on predictable port numbers and does not perform address translations inside a packet.

Many protocols open secondary TCP or UDP ports. The initial session on a well-known port is used to negotiate dynamically assigned port numbers.

Other applications embed an IP address in the packet that needs to match the source address that is normally translated when it goes through the adaptive security appliance.

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If you use applications like these, then you need to enable application inspection.

When you enable application inspection for a service that embeds IP addresses, the adaptive security appliance translates embedded addresses and updates any checksum or other fields that are affected by the translation.

When you enable application inspection for a service that uses dynamically assigned ports, the adaptive security appliance monitors sessions to identify the dynamic port assignments, and permits data exchange on these ports for the duration of the specific session.








State information for multimedia sessions that require inspection are not passed over the state link for stateful failover. The exception is GTP, which is replicated over the state link.

IPv6 Guidelines

Supports IPv6 for the following inspections:

•

•

•

•

•

•

FTP

HTTP

ICMP

SIP

SMTP

IPSec pass-through


Some inspection engines do not support PAT, NAT, outside NAT, or NAT between same security interfaces. See

“Default Settings”

for more information about NAT support.

For all the application inspections, the adaptive security appliance limits the number of simultaneous, active data connections to 200 connections. For example, if an FTP client opens multiple secondary connections, the FTP inspection engine allows only 200 active connections and the 201 connection is dropped and the adaptive security appliance generates a system error message.


By default, the configuration includes a policy that matches all default application inspection traffic and applies inspection to the traffic on all interfaces (a global policy). Default application inspection traffic includes traffic to the default ports for each protocol. You can only apply one global policy, so if you

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36-3



want to alter the global policy, for example, to apply inspection to non-standard ports, or to add inspections that are not enabled by default, you need to either edit the default policy or disable it and apply a new one.

Table 36-1 lists all inspections supported, the default ports used in the default class map, and the

inspection engines that are on by default, shown in bold. This table also notes any NAT limitations.

Table 36-1 Supported Application Inspection Engines

Application

CTIQBE

1

Default Port NAT Limitations

TCP/2748

—

DCERPC TCP/135

DNS

over UDP UDP/53

—

No NAT support is available for name resolution through

WINS.

Standards

—

—

RFC 1123

2

RFC 959

—

FTP

GTP

TCP/21

UDP/3386

UDP/2123

—

—

H.323 H.225

and

RAS

TCP/1720

UDP/1718

UDP (RAS)

1718-1719

HTTP TCP/80

No NAT on same security interfaces.

No static PAT.

—

ITU-T H.323,

H.245, H225.0,

Q.931, Q.932

RFC 2616

ICMP

ICMP ERROR

ILS (LDAP)

Instant

Messaging (IM)

IP Options

—

—

TCP/389

Varies by client

—

—

—

No PAT.

—

—

—

—

—

RFC 3860

Comments

—

—

No PTR records are changed.

—

Requires a special license.

—

Beware of MTU limitations stripping

ActiveX and Java. If the MTU is too small to allow the Java or ActiveX tag to be included in one packet, stripping may not occur.

All ICMP traffic is matched in the default class map.

All ICMP traffic is matched in the default class map.

—

—

RFC 791, RFC

2113

All IP Options traffic is matched in the default class map.

— —

RFC 2705bis-05 —

MMP

MGCP

NetBIOS Name

Server

over IP

PPTP

RADIUS

Accounting

RSH

TCP 5443 —

UDP/2427,

2727

UDP/137,

138 (Source ports)

—

—

TCP/1723 —

1646 —

TCP/514 No PAT

—

RFC 2637

RFC 2865

Berkeley UNIX

NetBIOS is supported by performing

NAT of the packets for NBNS UDP port

137 and NBDS UDP port 138.

—

—

—

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Configuring Application Layer Protocol Inspection

Table 36-1 Supported Application Inspection Engines (continued)

Application

RTSP

1

Default Port NAT Limitations

TCP/554 No PAT.

Standards

2

RFC 2326, 2327,

1889

Comments

No handling for HTTP cloaking.

SIP

SKINNY

(SCCP)

TCP/5060

UDP/5060

No outside NAT.

No outside NAT.


TCP/2000 No outside NAT.

TCP/25


—

RFC 2543

—

—

Does not handle TFTP uploaded Cisco

IP Phone configurations under certain circumstances.

SMTP

and

ESMTP

SNMP

SQL*Net

Sun RPC over

UDP

and TCP

TFTP

WAAS

XDCMP

UDP/161,

162

UDP/69

—

UDP/177

No NAT or PAT.

TCP/1521 —

UDP/111 No NAT or PAT.

—

—

No NAT or PAT.

RFC 821, 1123 —

RFC 1155, 1157,

1212, 1213, 1215 v.2 RFC 1902-1908; v.3 RFC

2570-2580.

—

— v.1 and v.2.

The default rule includes UDP port 111; if you want to enable Sun RPC inspection for TCP port 111, you need to create a new rule that matches TCP port 111 and performs Sun RPC inspection.

RFC 1350

—

—

Payload IP addresses are not translated.

—

—

1.

Inspection engines that are enabled by default for the default port are in bold.

2.

The adaptive security appliance is in compliance with these standards, but it does not enforce compliance on packets being inspected. For example, FTP commands are supposed to be in a particular order, but the adaptive security appliance does not enforce the order.


This feature uses Security Policy Rules to create a service policy. Service policies provide a consistent and flexible way to configure adaptive security appliance features. For example, you can use a service policy to create a timeout configuration that is specific to a particular TCP application, as opposed to

one that applies to all TCP applications. See Chapter 29, “Configuring a Service Policy,”


Inspection is enabled by default for some applications. See the

“Default Settings” section for more

information. Use this section to modify your inspection policy.

Detailed Steps

Step 1

Step 2

Choose

Configuration > Firewall > Service Policy Rules

.

Add or edit a service policy rule according to the “Adding a Service Policy Rule for Through Traffic” section on page 29-8 .

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36-5



Step 3

Step 4

Step 5

Step 6

Step 7

If you want to match non-standard ports, then create a new rule for the non-standard ports. See the

“Default Settings” section on page 36-3 for the standard ports for each inspection engine. You can

combine multiple rules in the same service policy if desired, so you can create one rule to match certain traffic, and another to match different traffic. However, if traffic matches a rule that contains an inspection action, and then matches another rule that also has an inspection action, only the first matching rule is used.

In the Edit Service Policy Rule > Rule Actions dialog box, click the

Protocol Inspection

tab.

For a new rule, the dialog box is called Add Service Policy Rule Wizard - Rule Actions.

Select each inspection type that you want to apply.

(Optional) Some inspection engines let you control additional parameters when you apply the inspection to the traffic. Click

Configure

for each inspection type to configure an inspect map.

You can either choose an existing map, or create a new one. You can predefine inspect maps in the

Configuration > Firewall > Objects > Inspect Maps pane.

You can configure other features for this rule if desired using the other Rule Actions tabs.

Click

OK

(or

Finish

from the wizard).

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C H A P T E R

37

Configuring Inspection of Basic Internet

Protocols

This chapter describes how to configure application layer protocol inspection. Inspection engines are required for services that embed IP addressing information in the user data packet or that open secondary channels on dynamically assigned ports. These protocols require the adaptive security appliance to do a deep packet inspection instead of passing the packet through the fast path. As a result, inspection engines can affect overall throughput.

Several common inspection engines are enabled on the adaptive security appliance by default, but you might need to enable others depending on your network. This chapter includes the following sections:

•

DNS Inspection, page 37-1

•

•

•

•

•

•

•

•

•

•

•

FTP Inspection, page 37-13

HTTP Inspection, page 37-23

ICMP Inspection, page 37-38

ICMP Error Inspection, page 37-39

Instant Messaging Inspection, page 37-39

IP Options Inspection, page 37-40

IPSec Pass Through Inspection, page 37-44

NetBIOS Inspection, page 37-48

PPTP Inspection, page 37-50

SMTP and Extended SMTP Inspection, page 37-50

TFTP Inspection, page 37-60

DNS Inspection

This section describes DNS application inspection. This section includes the following topics:

•

How DNS Application Inspection Works, page 37-2

•

•

How DNS Rewrite Works, page 37-3

Configuring DNS Rewrite, page 37-3

•

•

Select DNS Inspect Map, page 37-5

DNS Class Map, page 37-6

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37-1

DNS Inspection

Chapter 37 Configuring Inspection of Basic Internet Protocols

•

•

•

•

•

Add/Edit DNS Traffic Class Map, page 37-6

Add/Edit DNS Match Criterion, page 37-7

DNS Inspect Map, page 37-8

Add/Edit DNS Policy Map (Security Level), page 37-10

Add/Edit DNS Policy Map (Details), page 37-11

How DNS Application Inspection Works

The adaptive security appliance tears down the DNS session associated with a DNS query as soon as the

DNS reply is forwarded by the adaptive security appliance. The adaptive security appliance also monitors the message exchange to ensure that the ID of the DNS reply matches the ID of the DNS query.

When DNS inspection is enabled, which is the default, the adaptive security appliance performs the following additional tasks:

•

Translates the DNS record based on the configuration completed using the

alias

,

static

and

nat

commands (DNS Rewrite). Translation only applies to the A-record in the DNS reply; therefore,

DNS Rewrite does not affect reverse lookups, which request the PTR record.

Note

DNS Rewrite is not applicable for PAT because multiple PAT rules are applicable for each

A-record and the PAT rule to use is ambiguous.

•

Enforces the maximum DNS message length (the default is 512 bytes and the maximum length is

65535 bytes). The adaptive security appliance performs reassembly as needed to verify that the packet length is less than the maximum length configured. The adaptive security appliance drops the packet if it exceeds the maximum length.

Note

If you enter the

inspect dns

command without the

maximum-length

option, DNS packet size is not checked

•

•

Enforces a domain-name length of 255 bytes and a label length of 63 bytes.

Verifies the integrity of the domain-name referred to by the pointer if compression pointers are encountered in the DNS message.

Checks to see if a compression pointer loop exists.

•

A single connection is created for multiple DNS sessions, as long as they are between the same two hosts, and the sessions have the same 5-tuple (source/destination IP address, source/destination port, and protocol). DNS identification is tracked by

app_id

, and the idle timer for each app_id runs independently.

Because the app_id expires independently, a legitimate DNS response can only pass through the adaptive security appliance within a limited period of time and there is no resource build-up. However, if you enter the

show conn

command, you will see the idle timer of a DNS connection being reset by a new

DNS session. This is due to the nature of the shared DNS connection and is by design.

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DNS Inspection

How DNS Rewrite Works

When DNS inspection is enabled, DNS rewrite provides full support for NAT of DNS messages originating from any interface.

If a client on an inside network requests DNS resolution of an inside address from a DNS server on an outside interface, the DNS A-record is translated correctly. If the DNS inspection engine is disabled, the

A-record is not translated.

As long as DNS inspection remains enabled, you can configure DNS rewrite using a NAT rule.

DNS Rewrite performs two functions:

•

Translating a public address (the routable or “mapped” address) in a DNS reply to a private address

(the “real” address) when the DNS client is on a private interface.

Translating a private address to a public address when the DNS client is on the public interface.

•

In

Figure 37-1 , the DNS server resides on the external (ISP) network The real address of the server

(192.168.100.1) has been mapped using the

static

command to the ISP-assigned address

(209.165.200.5). When a web client on the inside interface attempts to access the web server with the

URL http://server.example.com, the host running the web client sends a DNS request to the DNS server to resolve the IP address of the web server. The adaptive security appliance translates the non-routable source address in the IP header and forwards the request to the ISP network on its outside interface.

When the DNS reply is returned, the adaptive security appliance applies address translation not only to the destination address, but also to the embedded IP address of the web server, which is contained in the

A-record in the DNS reply. As a result, the web client on the inside network gets the correct address for connecting to the web server on the inside network.

Figure 37-1 Translating the Address in a DNS Reply (DNS Rewrite)

DNS server server.example.com IN A 209.165.200.5

Web server server.example.com

192.168.100.1

Security appliance

192.168.100.1IN A 209.165.200.5

ISP Internet

Web client http://server.example.com

192.168.100.2

DNS rewrite also works if the client making the DNS request is on a DMZ network and the DNS server is on an inside interface.

Configuring DNS Rewrite

You configure DNS rewrite using the NAT configuration.

Figure 37-2 provides a more complex scenario to illustrate how DNS inspection allows NAT to operate

transparently with a DNS server with minimal configuration.

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37-3

DNS Inspection


Figure 37-2 DNS Rewrite with Three NAT Zones

DNS server erver.example.com IN A 209.165.200.5

99.99.99.2

Outside

Inside

Security appliance

DMZ

192.168.100.1

Web server

192.168.100.10

10.10.10.1

Web client

10.10.10.25

In

Figure 37-2

, a web server, server.example.com, has the real address 192.168.100.10 on the DMZ interface of the adaptive security appliance. A web client with the IP address 10.10.10.25 is on the inside interface and a public DNS server is on the outside interface. The site NAT policies are as follows:

•

•

The outside DNS server holds the authoritative address record for server.example.com.

Hosts on the outside network can contact the web server with the domain name server.example.com through the outside DNS server or with the IP address 209.165.200.5.

•

Clients on the inside network can access the web server with the domain name server.example.com through the outside DNS server or with the IP address 192.168.100.10.

When a host or client on any interface accesses the DMZ web server, it queries the public DNS server for the A-record of server.example.com. The DNS server returns the A-record showing that server.example.com binds to address 209.165.200.5.

When a web client on the

outside

network attempts to access http://server.example.com, the sequence of events is as follows:

1.

The host running the web client sends the DNS server a request for the IP address of server.example.com.

2.

3.

The DNS server responds with the IP address 209.165.200.225 in the reply.

The web client sends its HTTP request to 209.165.200.225.

4.

5.

The packet from the outside host reaches the adaptive security appliance at the outside interface.

The static rule translates the address 209.165.200.225 to 192.168.100.10 and the adaptive security appliance directs the packet to the web server on the DMZ.

When a web client on the

inside

network attempts to access http://server.example.com, the sequence of events is as follows:

1.

The host running the web client sends the DNS server a request for the IP address of server.example.com.

2.

The DNS server responds with the IP address 209.165.200.225 in the reply.

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DNS Inspection

3.

4.

The adaptive security appliance receives the DNS reply and submits it to the DNS application inspection engine.

The DNS application inspection engine does the following:

a.

Searches for any NAT rule to undo the translation of the embedded A-record address

“[outside]:209.165.200.5”. In this example, it finds the following static configuration: static (dmz,outside) 209.165.200.225 192.168.100.10 dns

b.

Uses the static rule to rewrite the A-record as follows because the

dns

option is included:

[outside]:209.165.200.225 --> [dmz]:192.168.100.10

Note

If the

dns

option were not included with the

static

command, DNS Rewrite would not be performed and other processing for the packet continues.

5.

c.

Searches for any NAT to translate the web server address, [dmz]:192.168.100.10, when communicating with the inside web client.

No NAT rule is applicable, so application inspection completes.

If a NAT rule (nat or static) were applicable, the

dns

option must also be specified. If the

dns

option were not specified, the A-record rewrite in step b

would be reverted and other processing for the packet continues.

The adaptive security appliance sends the HTTP request to server.example.com on the DMZ interface.

Select DNS Inspect Map

The Select DNS Map dialog box is accessible as follows:

Add/Edit Service Policy Rule Wizard > Rule Actions >

Protocol Inspection Tab >Select DNS Inspect Map

The Select DNS Map dialog box lets you select or create a new DNS map. A DNS map lets you change the configuration values used for DNS application inspection. The Select DNS Map table provides a list of previously configured maps that you can select for application inspection.

Fields

•

Use the default DNS inspection map—Specifies to use the default DNS map.

•

Select a DNS map for fine control over inspection

—

Lets you select a defined application inspection map or add a new one.

•

•

Enable Botnet traffic filter DNS snooping— Enables Botnet Traffic Filter snooping, which compares the domain name with those on the dynamic database or static database, and adds the name and IP address to the Botnet Traffic Filter DNS reverse lookup cache. This cache is then used by the

Botnet Traffic Filter when connections are made to the suspicious address. We suggest that you enable DNS snooping only on interfaces where external DNS requests are going. Enabling DNS snooping on all UDP DNS traffic, including that going to an internal DNS server, creates unnecessary load on the adaptive security appliance. For example, if the DNS server is on the outside interface, you should enable DNS inspection with snooping for all UDP DNS traffic on the outside interface.

Add—Opens the Add Policy Map dialog box for the inspection.

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DNS Inspection

DNS Class Map

The DNS Class Map dialog box is accessible as follows:

Configuration > Global Objects > Class Maps > DNS

The DNS Class Map pane lets you configure DNS class maps for DNS inspection.

An inspection class map matches application traffic with criteria specific to the application. You then identify the class map in the inspect map and enable actions. The difference between creating a class map and defining the traffic match directly in the inspect map is that you can create more complex match criteria and you can reuse class maps. The applications that support inspection class maps are DNS, FTP,

H.323, HTTP, IM, and SIP.

Fields

•

Name—Shows the DNS class map name.

•

Match Conditions—Shows the type, match criterion, and value in the class map.

–

Match Type—Shows the match type, which can be a positive or negative match.

–

–

Criterion—Shows the criterion of the DNS class map.

Value—Shows the value to match in the DNS class map.

•

•

•

•

Description—Shows the description of the class map.

Add—Adds match conditions for the DNS class map.

Edit—Edits match conditions for the DNS class map.

Delete—Deletes match conditions for the DNS class map.

Modes


Firewall Mode

Routed


Multiple

Transparent Single Context

• • • •

System

—

Add/Edit DNS Traffic Class Map

The Add/Edit DNS Traffic Class Map dialog box is accessible as follows:

Configuration > Global Objects > Class Maps > DNS > Add/Edit DNS Traffic Class Map

The Add/Edit DNS Traffic Class Map dialog box lets you define a DNS class map.

Fields

•

Name—Enter the name of the DNS class map, up to 40 characters in length.

•

•

Description—Enter the description of the DNS class map.

Add—Adds a DNS class map.

•

Edit—Edits a DNS class map.

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•

Delete—Deletes a DNS class map.

Modes


DNS Inspection

Firewall Mode

Routed



Multiple

Context

• • • •

System

—

Add/Edit DNS Match Criterion

The Add/Edit DNS Match Criterion dialog box is accessible as follows:

Configuration > Global Objects > Class Maps > DNS > Add/Edit DNS Traffic Class Map >

Add/Edit DNS Match Criterion

The Add/Edit DNS Match Criterion dialog box lets you define the match criterion and value for the DNS class map.

Fields

•

Match Type—Specifies whether the class map includes traffic that matches the criterion, or traffic that does not match the criterion.

•

For example, if No Match is selected on the string “example.com,” then any traffic that contains

“example.com” is excluded from the class map.

Criterion—Specifies which criterion of DNS traffic to match.

–

–

–

–

Header Flag—Match a DNS flag in the header.

Type—Match a DNS query or resource record type.

Class—Match a DNS query or resource record class.

Question—Match a DNS question.

•

•

–

–

Header Flag Criterion Values—Specifies the value details for the DNS header flag match.

–

Match Option—Specifies either an exact match or match all bits (bit mask match).

–

Resource Record—Match a DNS resource record.

Domain Name—Match a domain name from a DNS query or resource record.

Match Value—Specifies to match either the header flag name or the header flag value.

Header Flag Name—Lets you select one or more header flag names to match, including AA

(authoritative answer), QR (query), RA (recursion available), RD (recursion denied), TC

(truncation) flag bits.

Header Flag Value—Lets you enter an arbitrary 16-bit value in hex to match.

Type Criterion Values—Specifies the value details for the DNS type match.

–

DNS Type Field Name—Lists the DNS types to select.

A—IPv4 address

NS—Authoritative name server

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DNS Inspection


•

•

•

•

CNAME—Canonical name

SOA—Start of a zone of authority

TSIG—Transaction signature

–

IXFR—Incremental (zone) transfer

AXFR—Full (zone) transfer

DNS Type Field Value—Specifies to match either a DNS type field value or a DNS type field range.

Value—Lets you enter an arbitrary value between 0 and 65535 to match.

Range—Lets you enter a range match. Both values between 0 and 65535.

Class Criterion Values—Specifies the value details for the DNS class match.

–

–

DNS Class Field Name—Specifies to match on internet, the DNS class field name.

DNS Class Field Value—Specifies to match either a DNS class field value or a DNS class field range.

Value—Lets you enter an arbitrary value between 0 and 65535 to match.

Range—Lets you enter a range match. Both values between 0 and 65535.

Question Criterion Values—Specifies to match on the DNS question section.

Resource Record Criterion Values—Specifies to match on the DNS resource record section.

–

Resource Record— Lists the sections to match.

Additional—DNS additional resource record

Domain Name Criterion Values—Specifies to match on the DNS domain name.

–

Regular Expression—Lists the defined regular expressions to match.

–

Answer—DNS answer resource record

Authority—DNS authority resource record

–

Manage—Opens the Manage Regular Expressions dialog box, which lets you configure regular expressions.

Regular Expression Class—Lists the defined regular expression classes to match.

–

Manage—Opens the Manage Regular Expression Class dialog box, which lets you configure regular expression class maps.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

DNS Inspect Map

The DNS Inspect Map dialog box is accessible as follows:


37-8 OL-20339-01


DNS Inspection

Configuration > Global Objects > Inspect Maps > DNS

The DNS pane lets you view previously configured DNS application inspection maps. A DNS map lets you change the default configuration values used for DNS application inspection.

DNS application inspection supports DNS message controls that provide protection against DNS spoofing and cache poisoning. User configurable rules allow certain DNS types to be allowed, dropped, and/or logged, while others are blocked. Zone transfer can be restricted between servers with this function, for example.

The Recursion Desired and Recursion Available flags in the DNS header can be masked to protect a public server from attack if that server only supports a particular internal zone. In addition, DNS randomization can be enabled avoid spoofing and cache poisoning of servers that either do not support randomization, or utilize a weak pseudo random number generator. Limiting the domain names that can be queried also restricts the domain names which can be queried, which protects the public server further.

A configurable DNS mismatch alert can be used as notification if an excessive number of mismatching

DNS responses are received, which could indicate a cache poisoning attack. In addition, a configurable check to enforce a Transaction Signature be attached to all DNS messages is also supported.

Fields

•

DNS Inspect Maps—Table that lists the defined DNS inspect maps.

•

•

Add—Configures a new DNS inspect map. To edit a DNS inspect map, choose the DNS entry in the

DNS Inspect Maps table and click

Customize

.

Delete—Deletes the inspect map selected in the DNS Inspect Maps table.

•

Security Level—Select the security level (high, medium, or low).

–

Low—Default.

DNS Guard: enabled

NAT rewrite: enabled

–

Protocol enforcement: enabled

ID randomization: disabled

Message length check: enabled

Message length maximum: 512

Mismatch rate logging: disabled

TSIG resource record: not enforced

Medium

DNS Guard: enabled

–



ID randomization: enabled



Mismatch rate logging: enabled


High


OL-20339-01 37-9

DNS Inspection


•

•

DNS Guard: enabled







TSIG resource record: enforced

Customize—Opens the Add/Edit DNS Policy Map dialog box for additional settings.

Default Level—Sets the security level back to the default level of Low.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit DNS Policy Map (Security Level)

The Add/Edit DNS Policy Map dialog box is accessible as follows:

Configuration > Global Objects >

Inspect Maps > DNS > DNS Inspect Map > Basic View

The Add/Edit DNS Policy Map pane lets you configure the security level and additional settings for DNS application inspection maps.

Fields

•

Name—When adding a DNS map, enter the name of the DNS map. When editing a DNS map, the name of the previously configured DNS map is shown.

•

•

Description—Enter the description of the DNS map, up to 200 characters in length.


–

Low—Default.

DNS Guard: enabled



ID randomization: disabled



Mismatch rate logging: disabled


37-10


OL-20339-01


DNS Inspection

•

–

–

Medium

DNS Guard: enabled








High

DNS Guard: enabled





–



TSIG resource record: enforced


Details—Shows the Protocol Conformance, Filtering, Mismatch Rate, and Inspection tabs to configure additional settings.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit DNS Policy Map (Details)

The Add/Edit DNS Policy Map pane lets you configure the security level and additional settings for DNS application inspection maps

Fields

•

Name—When adding a DNS map, enter the name of the DNS map. When editing a DNS map, the name of the previously configured DNS map is shown.

•


•

Security Level—Shows the security level to configure.

OL-20339-01


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DNS Inspection


•

•

•

•

Protocol Conformance—Tab that lets you configure the protocol conformance settings for DNS.

–

–

Enable DNS guard function—Performs a DNS query and response mismatch check using the identification field in the DNS header. One response per query is allowed to go through the security appliance.

Enable NAT re-write function—Enables IP address translation in the A record of the DNS response.

–

–

Enable protocol enforcement—Enables DNS message format check, including domain name, label length, compression, and looped pointer check.

Randomize the DNS identifier for DNS query— Randomizes the DNS identifier in the DNS query message.

–

Enforce TSIG resource record to be present in DNS message—Requires that a TSIG resource record be present in DNS transactions. Actions taken when TSIG is enforced:

Drop packet—Drops the packet (logging can be either enabled or disabled).

Log—Enables logging.

Filtering—Tab that lets you configure the filtering settings for DNS.

–

Global Settings—Applies settings globally.

Drop packets that exceed specified maximum length (global)—Drops packets that exceed maximum length in bytes.

–

Maximum Packet Length—Enter maximum packet length in bytes.

Server Settings—Applies settings on the server only.

–

Drop packets that exceed specified maximum length——Drops packets that exceed maximum length in bytes.


Drop packets sent to server that exceed length indicated by the RR—Drops packets sent to the server that exceed the length indicated by the Resource Record.

Client Settings—Applies settings on the client only.

Drop packets sent to client that exceed length indicated by the RR—Drops packets sent to the client that exceed the length indicated by the Resource Record.

Mismatch Rate—Tab that lets you configure the ID mismatch rate for DNS.

–

Drop packets that exceed specified maximum length——Drops packets that exceed maximum length in bytes.


Enable Logging when DNS ID mismatch rate exceeds specified rate—Reports excessive instances of DNS identifier mismatches.

Mismatch Instance Threshold—Enter the maximum number of mismatch instances before a system message log is sent.

Time Interval—Enter the time period to monitor (in seconds).

Inspections—Tab that shows you the DNS inspection configuration and lets you add or edit.

–

–


Criterion—Shows the criterion of the DNS inspection.

–

Value—Shows the value to match in the DNS inspection.

37-12


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–

–

–

–

–

–

–

Action—Shows the action if the match condition is met.

Log—Shows the log state.

Add—Opens the Add DNS Inspect dialog box to add a DNS inspection.

Edit—Opens the Edit DNS Inspect dialog box to edit a DNS inspection.

Delete—Deletes a DNS inspection.

Move Up—Moves an inspection up in the list.

Move Down—Moves an inspection down in the list.

Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

FTP Inspection

FTP Inspection

•

•

•

This section describes the FTP inspection engine. This section includes the following topics:

•

•

FTP Inspection Overview, page 37-13

Using Strict FTP, page 37-14

•

•

Select FTP Map, page 37-15

FTP Class Map, page 37-15

Add/Edit FTP Traffic Class Map, page 37-16

Add/Edit FTP Match Criterion, page 37-16

FTP Inspect Map, page 37-18

FTP Inspection Overview

The FTP application inspection inspects the FTP sessions and performs four tasks:

•

•

•

Prepares dynamic secondary data connection

Tracks the FTP command-response sequence

•

Generates an audit trail

Translates the embedded IP address

FTP application inspection prepares secondary channels for FTP data transfer. Ports for these channels are negotiated through PORT or PASV commands. The channels are allocated in response to a file upload, a file download, or a directory listing event.

OL-20339-01


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FTP Inspection

Note

If you disable FTP inspection engines with the

no inspect ftp

command, outbound users can start connections only in passive mode, and all inbound FTP is disabled.

Using Strict FTP

Using strict FTP increases the security of protected networks by preventing web browsers from sending embedded commands in FTP requests. To enable strict FTP, click the

Configure

button next to FTP on the Configuration > Firewall > Service Policy Rules > Edit Service Policy Rule > Rule Actions >

Protocol Inspection tab.

After you enable the

strict

option on an interface, FTP inspection enforces the following behavior:

•

An FTP command must be acknowledged before the adaptive security appliance allows a new command.

•

•

The adaptive security appliance drops connections that send embedded commands.

The 227 and PORT commands are checked to ensure they do not appear in an error string.

Caution

Using the

strict

option may cause the failure of FTP clients that are not strictly compliant with FTP

RFCs.

If the

strict

option is enabled, each FTP command and response sequence is tracked for the following anomalous activity:

•

•

Truncated command—Number of commas in the PORT and PASV reply command is checked to see if it is five. If it is not five, then the PORT command is assumed to be truncated and the TCP connection is closed.

Incorrect command—Checks the FTP command to see if it ends with <CR><LF> characters, as required by the RFC. If it does not, the connection is closed.

•

Size of RETR and STOR commands—These are checked against a fixed constant. If the size is greater, then an error message is logged and the connection is closed.

•

•

•

•

Command spoofing—The PORT command should always be sent from the client. The TCP connection is denied if a PORT command is sent from the server.

Reply spoofing—PASV reply command (227) should always be sent from the server. The TCP connection is denied if a PASV reply command is sent from the client. This prevents the security hole when the user executes “227 xxxxx a1, a2, a3, a4, p1, p2.”

TCP stream editing—The adaptive security appliance closes the connection if it detects TCP stream editing.

Invalid port negotiation—The negotiated dynamic port value is checked to see if it is less than 1024.

As port numbers in the range from 1 to 1024 are reserved for well-known connections, if the negotiated port falls in this range, then the TCP connection is freed.

•

•

Command pipelining—The number of characters present after the port numbers in the PORT and

PASV reply command is cross checked with a constant value of 8. If it is more than 8, then the TCP connection is closed.

The adaptive security appliance replaces the FTP server response to the SYST command with a series of Xs. to prevent the server from revealing its system type to FTP clients. To override this default behavior, use the

no mask-syst-reply

command in the FTP map.

37-14


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FTP Inspection

Select FTP Map

The Select FTP Map dialog box is accessible as follows:

Add/Edit Service Policy Rule Wizard > Rule Actions > Protocol Inspection Tab >

Select FTP Map

The Select FTP Map dialog box lets you enable strict FTP application inspection, select an FTP map, or create a new FTP map. An FTP map lets you change the configuration values used for FTP application inspection.The Select FTP Map table provides a list of previously configured maps that you can select for application inspection.

Fields

•

FTP Strict (prevent web browsers from sending embedded commands in FTP requests)

—

Enables strict FTP application inspection, which causes the adaptive security appliance to drop the connection when an embedded command is included in an FTP request.

•

Use the default FTP inspection map—Specifies to use the default FTP map.

•

•

Select an FTP map for fine control over inspection

—



Modes


Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

FTP Class Map

The FTP Class Map dialog box is accessible as follows:

Configuration > Global Objects > Class Maps

> FTP

The FTP Class Map pane lets you configure FTP class maps for FTP inspection.



Fields

•

Name—Shows the FTP class map name.

•


–


–

–

Criterion—Shows the criterion of the FTP class map.

Value—Shows the value to match in the FTP class map.

OL-20339-01


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FTP Inspection


•

•

•

•


Add—Adds an FTP class map.

Edit—Edits an FTP class map.

Delete—Deletes an FTP class map.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit FTP Traffic Class Map

The Add/Edit FTP Traffic Class Map dialog box is accessible as follows:

Configuration > Global Objects > Class Maps > FTP > Add/Edit FTP Traffic Class Map

The Add/Edit FTP Traffic Class Map dialog box lets you define a FTP class map.

Fields

•

Name—Enter the name of the FTP class map, up to 40 characters in length.

•

Description—Enter the description of the FTP class map.

•

•

•

Add—Adds an FTP class map.

Edit—Edits an FTP class map.

Delete—Deletes an FTP class map.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit FTP Match Criterion

The Add/Edit FTP Match Criterion dialog box is accessible as follows:

Configuration > Global Objects > Class Maps > FTP > Add/Edit FTP Traffic Class Map >

Add/Edit FTP Match Criterion

The Add/Edit FTP Match Criterion dialog box lets you define the match criterion and value for the FTP class map.

37-16


OL-20339-01


FTP Inspection

Fields

•




•

Criterion—Specifies which criterion of FTP traffic to match.

–

Request-Command—Match an FTP request command.

–

–

File Name—Match a filename for FTP transfer.

File Type—Match a file type for FTP transfer.

•

–

–

Server—Match an FTP server.

User Name—Match an FTP user.

Request-Command Criterion Values—Specifies the value details for the FTP request command match.

–

Request Command—Lets you select one or more request commands to match.

•

•

APPE—Append to a file.

CDUP—Change to the parent of the current directory.

DELE—Delete a file at the server site.

GET—FTP client command for the retr (retrieve a file) command.

HELP—Help information from the server.

MKD—Create a directory.

PUT—FTP client command for the stor (store a file) command.

RMD—Remove a directory.

RNFR—Rename from.

RNTO—Rename to.

SITE—Specify a server specific command.

STOU—Store a file with a unique name.

File Name Criterion Values—Specifies to match on the FTP transfer filename.

–


–

–



–


File Type Criterion Values—Specifies to match on the FTP transfer file type.

–

–



–

–



OL-20339-01


37-17

FTP Inspection


•

•

Server Criterion Values—Specifies to match on the FTP server.

–

–



–

–



User Name Criterion Values—Specifies to match on the FTP user.

–


–

–



–


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

FTP Inspect Map

The FTP Inspect Map dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > FTP

The FTP pane lets you view previously configured FTP application inspection maps. An FTP map lets you change the default configuration values used for FTP application inspection.

FTP command filtering and security checks are provided using strict FTP inspection for improved security and control. Protocol conformance includes packet length checks, delimiters and packet format checks, command terminator checks, and command validation.

Blocking FTP based on user values is also supported so that it is possible for FTP sites to post files for download, but restrict access to certain users. You can block FTP connections based on file type, server name, and other attributes. System message logs are generated if an FTP connection is denied after inspection.

Fields

•

FTP Inspect Maps—Table that lists the defined FTP inspect maps.

•

Add—Configures a new FTP inspect map. To edit an FTP inspect map, choose the FTP entry in the

FTP Inspect Maps table and click

Customize

.

•

Delete—Deletes the inspect map selected in the FTP Inspect Maps table.

37-18


OL-20339-01


FTP Inspection

•

Security Level—Select the security level (medium or low).

–

Low

Mask Banner Disabled

–

Mask Reply Disabled

Medium—Default.

Mask Banner Enabled

Mask Reply Enabled

–

–

–

File Type Filtering—Opens the Type Filtering dialog box to configure file type filters.

Customize—Opens the Add/Edit FTP Policy Map dialog box for additional settings.

Default Level—Sets the security level back to the default level of Medium.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

File Type Filtering

The File Type Filtering dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > FTP > MIME File Type Filtering

The File Type Filtering dialog box lets you configure the settings for a file type filter.

Fields

•


•

Criterion—Shows the criterion of the inspection.

•

•

•

•

•

Value—Shows the value to match in the inspection.



Add—Opens the Add File Type Filter dialog box to add a file type filter.

•

•

•

Edit—Opens the Edit File Type Filter dialog box to edit a file type filter.

Delete—Deletes a file type filter.

Move Up—Moves an entry up in the list.

Move Down—Moves an entry down in the list.

Modes


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37-19


FTP Inspection

Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

Add/Edit FTP Policy Map (Security Level)

The Add/Edit FTP Policy Map dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > FTP > FTP Inspect Map > Basic View

The Add/Edit FTP Policy Map pane lets you configure the security level and additional settings for FTP application inspection maps.

Fields

•

Name—When adding an FTP map, enter the name of the FTP map. When editing an FTP map, the name of the previously configured FTP map is shown.

•

•

Description—Enter the description of the FTP map, up to 200 characters in length.

Security Level—Select the security level (medium or low).

–

Low

Mask Banner Disabled

•

–

Mask Reply Disabled

Medium—Default.

–

–

Mask Banner Enabled

Mask Reply Enabled

File Type Filtering—Opens the Type Filtering dialog box to configure file type filters.


Details—Shows the Parameters and Inspections tabs to configure additional settings.

Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

Add/Edit FTP Policy Map (Details)

The Add/Edit FTP Policy Map (Details) dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > FTP > FTP Inspect Map > Advanced View

37-20


OL-20339-01


FTP Inspection

The Add/Edit FTP Policy Map pane lets you configure the security level and additional settings for FTP application inspection maps.

•

•

•

Fields

•

Name—When adding an FTP map, enter the name of the FTP map. When editing an FTP map, the name of the previously configured FTP map is shown.

Description—Enter the description of the FTP map, up to 200 characters in length.

Security Level—Shows the security level and file type filtering settings to configure.

Parameters—Tab that lets you configure the parameters for the FTP inspect map.

–

Mask greeting banner from the server—Masks the greeting banner from the FTP server to prevent the client from discovering server information.

•

–

Mask reply to SYST command—Masks the reply to the syst command to prevent the client from discovering server information.

Inspections—Tab that shows you the FTP inspection configuration and lets you add or edit.

–

–

–

–

–

–

–

–

–

–


Criterion—Shows the criterion of the FTP inspection.

Value—Shows the value to match in the FTP inspection.



Add—Opens the Add FTP Inspect dialog box to add an FTP inspection.

Edit—Opens the Edit FTP Inspect dialog box to edit an FTP inspection.

Delete—Deletes an FTP inspection.



Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit FTP Map

The Add/Edit FTP Map dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > FTP > FTP Inspect Map > Advanced View >

Add/Edit FTP Inspect

The Add/Edit FTP Inspect dialog box lets you define the match criterion and value for the FTP inspect map.

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FTP Inspection


Fields

•

Single Match—Specifies that the FTP inspect has only one match statement.

•

Match Type—Specifies whether traffic should match or not match the values.

•



Criterion—Specifies which criterion of FTP traffic to match.

–

–

Request Command—Match an FTP request command.

File Name—Match a filename for FTP transfer.

–

–

File Type—Match a file type for FTP transfer.

Server—Match an FTP server.

•

•

–

User Name—Match an FTP user.

Request Command Criterion Values—Specifies the value details for FTP request command match.

–

Request Command:

APPE—Command that appends to a file.

CDUP—Command that changes to the parent directory of the current working directory.

DELE—Command that deletes a file.

GET—Command that gets a file.

HELP—Command that provides help information.

MKD—Command that creates a directory.

PUT—Command that sends a file.

RMD—Command that deletes a directory.

RNFR—Command that specifies rename-from filename.

RNTO—Command that specifies rename-to filename.

SITE—Commands that are specific to the server system. Usually used for remote administration.

STOU—Command that stores a file using a unique filename.

File Name Criterion Values—Specifies the value details for FTP filename match.

•

–

–



–

–



File Type Criterion Values—Specifies the value details for FTP file type match.

–


–

–



37-22


OL-20339-01


HTTP Inspection

•

•

•

•

•

–

Server Criterion Values—Specifies the value details for FTP server match.

–


–


–



–


User Name Criterion Values—Specifies the value details for FTP user name match.

–

–



–

–



Multiple Matches—Specifies multiple matches for the FTP inspection.

–

FTP Traffic Class—Specifies the FTP traffic class match.

–

Manage—Opens the Manage FTP Class Maps dialog box to add, edit, or delete FTP Class

Maps.

Action—Reset.

Log—Enable or disable.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

HTTP Inspection

•

•

•

This section describes the HTTP inspection engine. This section includes the following topics:

•

HTTP Inspection Overview, page 37-24

Select HTTP Map, page 37-24

HTTP Class Map, page 37-25

•

Add/Edit HTTP Traffic Class Map, page 37-26

Add/Edit HTTP Match Criterion, page 37-26

•

HTTP Inspect Map, page 37-30

OL-20339-01


37-23

HTTP Inspection


•

•

•

•

“URI Filtering” section on page 37-31

“Add/Edit HTTP Policy Map (Security Level)” section on page 37-32

“Add/Edit HTTP Policy Map (Details)” section on page 37-33

“Add/Edit HTTP Map” section on page 37-34

HTTP Inspection Overview

Use the HTTP inspection engine to protect against specific attacks and other threats that may be associated with HTTP traffic. HTTP inspection performs several functions:

•

•

Enhanced HTTP inspection

URL screening through N2H2 or Websense

•

Java and ActiveX filtering

The latter two features are configured in conjunction with Filter rules.

The enhanced HTTP inspection feature, which is also known as an application firewall and is available when you configure an HTTP map, can help prevent attackers from using HTTP messages for circumventing network security policy. It verifies the following for all HTTP messages:

•

Conformance to RFC 2616

•

•

Use of RFC-defined methods only.

Compliance with the additional criteria.

Select HTTP Map

The Select HTTP Map dialog box is accessible as follows:


Select HTTP Map

The Select HTTP Map dialog box lets you select or create a new HTTP map. An HTTP map lets you change the configuration values used for HTTP application inspection. The Select HTTP Map table provides a list of previously configured maps that you can select for application inspection.

Fields

•

Use the default HTTP inspection map—Specifies to use the default HTTP map.

•

Select an HTTP map for fine control over inspection

—


•


Modes


37-24


OL-20339-01


HTTP Inspection

Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

HTTP Class Map

The HTTP Class Map dialog box is accessible as follows:

Configuration > Global Objects > Class Maps > HTTP

The HTTP Class Map pane lets you configure HTTP class maps for HTTP inspection.



Note

If you need to change a match condition for HTTP inspection after configuring the inspection, you must remove the attached service policy command and then reconfigure the service policy.

Changing the class map by removing a match condition causes HTTP inspection to block all

HTTP traffic until you remove and reconfigure the attached service policy so that all the match conditions are reprocessed.

Fields

•

Name—Shows the HTTP class map name.

•


•

•

–

–


Criterion—Shows the criterion of the HTTP class map.

–

Value—Shows the value to match in the HTTP class map.


•

•

Add—Adds an HTTP class map.

Edit—Edits an HTTP class map.

Delete—Deletes an HTTP class map.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

OL-20339-01


37-25


HTTP Inspection

Add/Edit HTTP Traffic Class Map

The Add/Edit HTTP Traffic Class Map dialog box is accessible as follows:

Configuration > Global Objects > Class Maps > HTTP > Add/Edit HTTP Traffic Class Map

The Add/Edit HTTP Traffic Class Map dialog box lets you define a HTTP class map.

Fields

•

Name—Enter the name of the HTTP class map, up to 40 characters in length.

•

Description—Enter the description of the HTTP class map.

•

•

•

Add—Adds an HTTP class map.

Edit—Edits an HTTP class map.

Delete—Deletes an HTTP class map.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit HTTP Match Criterion

The Add/Edit HTTP Match Criterion dialog box is accessible as follows:

Configuration > Global Objects > Class Maps > HTTP > Add/Edit HTTP Traffic Class Map >

Add/Edit HTTP Match Criterion

The Add/Edit HTTP Match Criterion dialog box lets you define the match criterion and value for the

HTTP class map.

Fields

•




•

Criterion—Specifies which criterion of HTTP traffic to match.

–

Request/Response Content Type Mismatch—Specifies that the content type in the response must match one of the MIME types in the accept field of the request.

–

Request Arguments—Applies the regular expression match to the arguments of the request.




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HTTP Inspection

–

–

–

–

–


Request Body Length—Applies the regular expression match to the body of the request with field length greater than the bytes specified.

Greater Than Length—Enter a field length value in bytes that request field lengths will be matched against.

Request Body—Applies the regular expression match to the body of the request.





Request Header Field Count—Applies the regular expression match to the header of the request with a maximum number of header fields.

Predefined—Specifies the request header fields: accept, accept-charset, accept-encoding, accept-language, allow, authorization, cache-control, connection, content-encoding, content-language, content-length, content-location, content-md5, content-range, content-type, cookie, date, expect, expires, from, host, if-match, if-modified-since, if-none-match, if-range, if-unmodified-since, last-modified, max-forwards, pragma, proxy-authorization, range, referer, te, trailer, transfer-encoding, upgrade, user-agent, via, warning.



Greater Than Count—Enter the maximum number of header fields.

Request Header Field Length—Applies the regular expression match to the header of the request with field length greater than the bytes specified.





Request Header Field—Applies the regular expression match to the header of the request.


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HTTP Inspection





–


Request Header Count—Applies the regular expression match to the header of the request with a maximum number of headers.

–

Greater Than Count—Enter the maximum number of headers.

Request Header Length—Applies the regular expression match to the header of the request with length greater than the bytes specified.

–

Greater Than Length—Enter a header length value in bytes.

Request Header non-ASCII—Matches non-ASCII characters in the header of the request.

–

Request Method—Applies the regular expression match to the method of the request.

Method—Specifies to match on a request method: bcopy, bdelete, bmove, bpropfind, bproppatch, connect, copy, delete, edit, get, getattribute, getattributenames, getproperties, head, index, lock, mkcol, mkdir, move, notify, options, poll, post, propfind, proppatch, put, revadd, revlabel, revlog, revnum, save, search, setattribute, startrev, stoprev, subscribe, trace, unedit, unlock, unsubscribe.

Regular Expression—Specifies to match on a regular expression.




–


Request URI Length—Applies the regular expression match to the URI of the request with length greater than the bytes specified.

–

Greater Than Length—Enter a URI length value in bytes.

Request URI—Applies the regular expression match to the URI of the request.





–

Response Body—Applies the regex match to the body of the response.

ActiveX—Specifies to match on ActiveX.

Java Applet—Specifies to match on a Java Applet.



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HTTP Inspection

–

–

–

–




Response Body Length—Applies the regular expression match to the body of the response with field length greater than the bytes specified.

Greater Than Length—Enter a field length value in bytes that response field lengths will be matched against.

Response Header Field Count—Applies the regular expression match to the header of the response with a maximum number of header fields.

Predefined—Specifies the response header fields: accept-ranges, age, allow, cache-control, connection, content-encoding, content-language, content-length, content-location, content-md5, content-range, content-type, date, etag, expires, last-modified, location, pragma, proxy-authenticate, retry-after, server, set-cookie, trailer, transfer-encoding, upgrade, vary, via, warning, www-authenticate.




Response Header Field Length—Applies the regular expression match to the header of the response with field length greater than the bytes specified.





Response Header Field—Applies the regular expression match to the header of the response.






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HTTP Inspection


–

Response Header Count—Applies the regular expression match to the header of the response with a maximum number of headers.

–


Response Header Length—Applies the regular expression match to the header of the response with length greater than the bytes specified.

–


Response Header non-ASCII—Matches non-ASCII characters in the header of the response.

–

Response Status Line—Applies the regular expression match to the status line.





Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

HTTP Inspect Map

The HTTP Inspect Map dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > HTTP

The HTTP pane lets you view previously configured HTTP application inspection maps. An HTTP map lets you change the default configuration values used for HTTP application inspection.

HTTP application inspection scans HTTP headers and body, and performs various checks on the data.

These checks prevent various HTTP constructs, content types, and tunneling and messaging protocols from traversing the security appliance.

HTTP application inspection can block tunneled applications and non-ASCII characters in HTTP requests and responses, preventing malicious content from reaching the web server. Size limiting of various elements in HTTP request and response headers, URL blocking, and HTTP server header type spoofing are also supported.

Fields

•

HTTP Inspect Maps—Table that lists the defined HTTP inspect maps.

•

Add—Configures a new HTTP inspect map. To edit an HTTP inspect map, choose the HTTP entry in the HTTP Inspect Maps table and click

Customize

.

•

Delete—Deletes the inspect map selected in the HTTP Inspect Maps table.

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HTTP Inspection

•

Security Level—Select the security level (low, medium, or high).

–

Low—Default.

Protocol violation action: Drop connection

Drop connections for unsafe methods: Disabled

Drop connections for requests with non-ASCII headers: Disabled

URI filtering: Not configured

Advanced inspections: Not configured

–

–

Medium


Drop connections for unsafe methods: Allow only GET, HEAD, and POST




High

Protocol violation action: Drop connection and log

–

–

–

Drop connections for unsafe methods: Allow only GET and HEAD.

Drop connections for requests with non-ASCII headers: Enabled



URI Filtering—Opens the URI Filtering dialog box to configure URI filters.

Customize—Opens the Edit HTTP Policy Map dialog box for additional settings.


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

URI Filtering

The URI Filtering dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > HTTP > URI Filtering

The URI Filtering dialog box lets you configure the settings for an URI filter.

Fields

•


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HTTP Inspection


•

•

•

•

•

•

•

•

•





Add—Opens the Add URI Filtering dialog box to add a URI filter.

Edit—Opens the Edit URI Filtering dialog box to edit a URI filter.

Delete—Deletes an URI filter.



Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

Add/Edit HTTP Policy Map (Security Level)

The Add/Edit HTTP Policy Map (Security Level) dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > HTTP > HTTP Inspect Map > Basic View

The Add/Edit HTTP Policy Map pane lets you configure the security level and additional settings for

HTTP application inspection maps.

Fields

•

Name—When adding an HTTP map, enter the name of the HTTP map. When editing an HTTP map, the name of the previously configured HTTP map is shown.

•

•

Description—Enter the description of the HTTP map, up to 200 characters in length.


–

Low—Default.


Drop connections for unsafe methods: Disabled




–

Medium


Drop connections for unsafe methods: Allow only GET, HEAD, and POST


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HTTP Inspection

•

–



High

Protocol violation action: Drop connection and log

Drop connections for unsafe methods: Allow only GET and HEAD.

Drop connections for requests with non-ASCII headers: Enabled


–


URI Filtering—Opens the URI Filtering dialog box which lets you configure the settings for an

URI filter.

–

Default Level—Sets the security level back to the default.


Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

Add/Edit HTTP Policy Map (Details)

The Add/Edit HTTP Policy Map (Details) dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > HTTP > HTTP Inspect Map > Advanced View

The Add/Edit HTTP Policy Map pane lets you configure the security level and additional settings for

HTTP application inspection maps.

Fields

•

Name—When adding an HTTP map, enter the name of the HTTP map. When editing an HTTP map, the name of the previously configured HTTP map is shown.

•

•

•

Description—Enter the description of the HTTP map, up to 200 characters in length.

Security Level—Shows the security level and URI filtering settings to configure.

Parameters—Tab that lets you configure the parameters for the HTTP inspect map.

–

Check for protocol violations—Checks for HTTP protocol violations.

–

Action—Drop Connection, Reset, Log.


Spoof server string—Replaces the server HTTP header value with the specified string.

Spoof String—Enter a string to substitute for the server header field. Maximum is 82 characters.

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HTTP Inspection


•

–

Body Match Maximum—The maximum number of characters in the body of an HTTP message that should be searched in a body match. Default is 200 bytes. A large number will have a significant impact on performance.

Inspections—Tab that shows you the HTTP inspection configuration and lets you add or edit.

–


–

–

Criterion—Shows the criterion of the HTTP inspection.

Value—Shows the value to match in the HTTP inspection.

–

–



–

–

Add—Opens the Add HTTP Inspect dialog box to add an HTTP inspection.

Edit—Opens the Edit HTTP Inspect dialog box to edit an HTTP inspection.

–

–

Delete—Deletes an HTTP inspection.


–


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit HTTP Map

The Add/Edit HTTP Map dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > HTTP > HTTP Inspect Map > Advanced View

> Add/Edit HTTP Inspect

The Add/Edit HTTP Inspect dialog box lets you define the match criterion and value for the HTTP inspect map.

Fields

•

Single Match—Specifies that the HTTP inspect has only one match statement.

•


•



Criterion—Specifies which criterion of HTTP traffic to match.

–

–

Request/Response Content Type Mismatch—Specifies that the content type in the response must match one of the MIME types in the accept field of the request.

Request Arguments—Applies the regular expression match to the arguments of the request.


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HTTP Inspection

–

–

–

–

–




Request Body Length—Applies the regular expression match to the body of the request with field length greater than the bytes specified.


Request Body—Applies the regular expression match to the body of the request.





Request Header Field Count—Applies the regular expression match to the header of the request with a maximum number of header fields.





Request Header Field Length—Applies the regular expression match to the header of the request with field length greater than the bytes specified.





Request Header Field—Applies the regular expression match to the header of the request.

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HTTP Inspection





–



Request Header Count—Applies the regular expression match to the header of the request with a maximum number of headers.


–

Request Header Length—Applies the regular expression match to the header of the request with length greater than the bytes specified.


–

–

Request Header non-ASCII—Matches non-ASCII characters in the header of the request.

Request Method—Applies the regular expression match to the method of the request.

Method—Specifies to match on a request method: bcopy, bdelete, bmove, bpropfind, bproppatch, connect, copy, delete, edit, get, getattribute, getattributenames, getproperties, head, index, lock, mkcol, mkdir, move, notify, options, poll, post, propfind, proppatch, put, revadd, revlabel, revlog, revnum, save, search, setattribute, startrev, stoprev, subscribe, trace, unedit, unlock, unsubscribe.






–

Request URI Length—Applies the regular expression match to the URI of the request with length greater than the bytes specified.

Greater Than Length—Enter a URI length value in bytes.

–

Request URI—Applies the regular expression match to the URI of the request.


–




Response Body—Applies the regex match to the body of the response.

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HTTP Inspection

–

–

–

–

ActiveX—Specifies to match on ActiveX.

Java Applet—Specifies to match on a Java Applet.






Response Body Length—Applies the regular expression match to the body of the response with field length greater than the bytes specified.


Response Header Field Count—Applies the regular expression match to the header of the response with a maximum number of header fields.





Response Header Field Length—Applies the regular expression match to the header of the response with field length greater than the bytes specified.





Response Header Field—Applies the regular expression match to the header of the response.



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ICMP Inspection


•

•

•




–

Response Header Count—Applies the regular expression match to the header of the response with a maximum number of headers.


–

Response Header Length—Applies the regular expression match to the header of the response with length greater than the bytes specified.


–

–

Response Header non-ASCII—Matches non-ASCII characters in the header of the response.

Response Status Line—Applies the regular expression match to the status line.





Multiple Matches—Specifies multiple matches for the HTTP inspection.

–

H323 Traffic Class—Specifies the HTTP traffic class match.

–

Manage—Opens the Manage HTTP Class Maps dialog box to add, edit, or delete HTTP Class

Maps.

Action—Drop connection, reset, or log.


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

ICMP Inspection

The ICMP inspection engine allows ICMP traffic to have a “session” so it can be inspected like TCP and

UDP traffic. Without the ICMP inspection engine, we recommend that you do not allow ICMP through the adaptive security appliance in an access list. Without stateful inspection, ICMP can be used to attack your network. The ICMP inspection engine ensures that there is only one response for each request, and that the sequence number is correct.

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ICMP Error Inspection

ICMP Error Inspection

When this feature is enabled, the adaptive security appliance creates translation sessions for intermediate hops that send ICMP error messages, based on the NAT configuration. The adaptive security appliance overwrites the packet with the translated IP addresses.

When disabled, the adaptive security appliance does not create translation sessions for intermediate nodes that generate ICMP error messages. ICMP error messages generated by the intermediate nodes between the inside host and the adaptive security appliance reach the outside host without consuming any additional NAT resource. This is undesirable when an outside host uses the traceroute command to trace the hops to the destination on the inside of the adaptive security appliance. When the adaptive security appliance does not translate the intermediate hops, all the intermediate hops appear with the mapped destination IP address.

The ICMP payload is scanned to retrieve the five-tuple from the original packet. Using the retrieved five-tuple, a lookup is performed to determine the original address of the client. The ICMP error inspection engine makes the following changes to the ICMP packet:

•

In the IP Header, the mapped IP is changed to the real IP (Destination Address) and the IP checksum is modified.

•

•

In the ICMP Header, the ICMP checksum is modified due to the changes in the ICMP packet.

In the Payload, the following changes are made:

–

–

Original packet mapped IP is changed to the real IP

Original packet mapped port is changed to the real Port

–

Original packet IP checksum is recalculated

Instant Messaging Inspection

This section describes the IM inspection engine. This section includes the following topics:

•

IM Inspection Overview, page 37-39

•

Select IM Map, page 37-39

IM Inspection Overview

The IM inspect engine lets you apply fine grained controls on the IM application to control the network usage and stop leakage of confidential data, propagation of worms, and other threats to the corporate network.

Select IM Map

The Select IM Map dialog box is accessible as follows:

Add/Edit Service Policy Rule Wizard > Rule Actions > Protocol Inspection Tab > Select IM Map

The Select IM Map dialog box lets you select or create a new IM map. An IM map lets you change the configuration values used for IM application inspection. The Select IM Map table provides a list of previously configured maps that you can select for application inspection.

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37-39


IP Options Inspection

Fields

•


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—


This section describes the IP Options inspection engine. This section includes the following topics:

•

•

•

•

•

IP Options Inspection Overview, page 37-40

Configuring IP Options Inspection, page 37-41

Select IP Options Inspect Map, page 37-42

IP Options Inspect Map, page 37-43

Add/Edit IP Options Inspect Map, page 37-43

IP Options Inspection Overview

Each IP packet contains an IP header with the Options field. The Options field, commonly referred to as

IP Options, provide for control functions that are required in some situations but unnecessary for most common communications. In particular, IP Options include provisions for time stamps, security, and special routing. Use of IP Options is optional, and the field can contain zero, one, or more options.

You can configure IP Options inspection to control which IP packets with specific IP options are allowed through the adaptive security appliance. Configuring this inspection instructs the adaptive security appliance to allow a packet to pass or to clear the specified IP options and then allow the packet to pass.

IP Options inspection can check for the following three IP options in a packet:

•

•

End of Options List (EOOL) or IP Option 0—This option, which contains just a single zero byte, appears at the end of all options to mark the end of a list of options. This might not coincide with the end of the header according to the header length.

No Operation (NOP) or IP Option 1—The Options field in the IP header can contain zero, one, or more options, which makes the total length of the field variable. However, the IP header must be a multiple of 32 bits. If the number of bits of all options is not a multiple of 32 bits, the NOP option is used as “internal padding” to align the options on a 32-bit boundary.

•

Router Alert (RTRALT) or IP Option 20—This option notifies transit routers to inspect the contents of the packet even when the packet is not destined for that router. This inspection is valuable when implementing RSVP and similar protocols require relatively complex processing from the routers along the packets delivery path.

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Note

IP Options inspection is included by default in the global inspection policy. Therefore, the adaptive security appliance allows RSVP traffic that contains packets with the Router Alert option (option 20) when the adaptive security appliance is in routed mode.

Dropping RSVP packets containing the Router Alert option can cause problems in VoIP implementations.

When you configure the adaptive security appliance to clear the Router Alert option from IP headers, the

IP header changes in the following ways:

•

•

The Options field is padded so that the field ends on a 32 bit boundary.

Internet header length (IHL) changes.

•

•

The total length of the packet changes.

The checksum is recomputed.

If an IP header contains additional options other than EOOL, NOP, or RTRALT, regardless of whether the adaptive security appliance is configured to allow these options, the adaptive security appliance will drop the packet.

Configuring IP Options Inspection

Use the Add Service Policy Rule Wizard - Rule Actions dialog box to configure IP Options inspection.

This wizard is available from the Configuration > Firewall > Service Policy Rules > Add > Add Service

Policy Rule Wizard - Rule Actions dialog box.

Step 1

Step 2

Step 3

Step 4

Step 5

Open the Add Service Policy Rule Wizard by selecting

Configuration > Firewall > Service Policy

Rules > Add

.

Perform the steps to complete the Service Policy, Traffic Classification Criteria, and Traffic Match -

Destination Port pages of the wizard. See the

“Adding a Service Policy Rule for Through Traffic” section on page 29-8 .

The Add Service Policy Rule Wizard - Rule Actions dialog box opens.

Check the

IP-Options

check box.

Click

Configure

.

The Select IP Options Inspect Map dialog box opens.

Perform one of the following:

•

Click the

Use the default IP-Options inspection map

radio button to use the default IP Options map. The default map drops packets containing all the inspected IP options, namely End of Options

List (EOOL), No Operation (NOP), and Router Alert (RTRALT).

•

•

Click the

Select an IP-Options inspect map for fine control over inspection

radio button to select a defined application inspection map.

Click Add to open the Add IP-Options Inspect Map dialog box and create a new inspection map.

(Optional) If you clicked

Add

to create a new inspection map, define the following values for IP Options

Inspection:

a.

Enter a name for the inspection map.

b.

Enter a description for the inspection map, up to 200 characters long.


OL-20339-01 37-41



Step 6

Step 7 c.

From the Parameters area, select which IP options you want to pass through the adaptive security appliance or clear and then pass through the adaptive security appliance:

–

Allow packets with the End of Options List (EOOL) option

This option, which contains just a single zero byte, appears at the end of all options to mark the end of a list of options. This might not coincide with the end of the header according to the header length.

–

Allow packets with the No Operation (NOP) option

The Options field in the IP header can contain zero, one, or more options, which makes the total length of the field variable. However, the IP header must be a multiple of 32 bits. If the number of bits of all options is not a multiple of 32 bits, the NOP option is used as “internal padding” to align the options on a 32-bit boundary.

–

Allow packets with the Router Alert (RTRALT) option

This option notifies transit routers to inspect the contents of the packet even when the packet is not destined for that router. This inspection is valuable when implementing RSVP and similar protocols require relatively complex processing from the routers along the packets delivery path.

–

Clear the option value from the packets

When an option is checked, the

Clear the option value from the packets

check box becomes available for that option. Select the


check box to clear the option from the packet before allowing the packet through the adaptive security appliance.

d.

Click

OK

.

Click

OK

.

Click

Finish

.

Select IP Options Inspect Map

The Select IP Options Inspect Map dialog box is accessible as follows:

Add/Edit Service Policy Rule Wizard > Rule Actions > Protocol Inspection Tab > Select IM Map

The Select IP-Options Inspect Map dialog box lets you select or create a new IP Options inspection map.

Use this inspection map to control whether the adaptive security appliance drops, passes, or clears IP packets containing the following IP options—End of Options List, No Operations, and Router Alert.

Fields

•

Use the default IP-Options inspection map—Specifies to use the default IP Options map. The default map drops packets containing all the inspected IP options, namely End of Options List (EOOL), No

Operation (NOP), and Router Alert (RTRALT).

•

•

Select an IP-Options map for fine control over inspection

—


Add—Opens the Add IP Options Inspect Map dialog box for the inspection.

Modes


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Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

IP Options Inspect Map

The IP Options Inspect Maps pane lets you view previously configured IP Options inspection maps. An

IP Options inspection map lets you change the default configuration values used for IP Option inspection.

You can configure IP Options inspection to control which IP packets with specific IP options are allowed through the security appliance. Configuring this inspection instructs the security appliance to allow a packet to pass or to clear the specified IP options and then allow the packet to pass.

In particular, you can control whether the security appliance drops, clears, or passes packets containing the Router Alert (RTRALT) option. Dropping RSVP packets containing the Router Alert option can cause problems in VoIP implementations. Therefore, you can create IP Options inspection maps to pass packets containing the RTRALT option.

Fields

IP Options Inspect Maps—Table that lists the defined IP Options inspect maps.

Add—Configures a new IP Options inspect map.

Edit—Edits an existing IP Options inspect map. To edit an IP Options inspect map, choose the entry in the table and click Edit.

Delete—Deletes the inspect map selected in the IP Options Inspect Maps table.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit IP Options Inspect Map

The Add/Edit IP Options Inspect Map lets you configure the settings for IP Options inspection maps.

Fields

•

Name—When adding an IP Options inspection map, enter the name of the map. When editing a map, the name of the previously configured map is shown.

•

Description—Enter the description of the IP Options inspection map, up to 200 characters in length.

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37-43


IPSec Pass Through Inspection

•

Parameters—Select which IP options you want to pass through the adaptive security appliance or clear and then pass through the adaptive security appliance:

–

Allow packets with the End of Options List (EOOL) option

This option, which contains just a single zero byte, appears at the end of all options to mark the end of a list of options. This might not coincide with the end of the header according to the header length.

–

Allow packets with the No Operation (NOP) option

The Options field in the IP header can contain zero, one, or more options, which makes the total length of the field variable. However, the IP header must be a multiple of 32 bits. If the number of bits of all options is not a multiple of 32 bits, the NOP option is used as “internal padding” to align the options on a 32-bit boundary.

–

Allow packets with the Router Alert (RTRALT) option

This option notifies transit routers to inspect the contents of the packet even when the packet is not destined for that router. This inspection is valuable when implementing RSVP and similar protocols require relatively complex processing from the routers along the packets delivery path.

–

Clear the option value from the packets

When an option is checked, the


check box becomes available for that option. Select the


check box to clear the option from the packet before allowing the packet through the adaptive security appliance.

Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—


•

•

•

This section describes the IPSec Pass Through inspection engine. This section includes the following topics:

•

•

IPSec Pass Through Inspection Overview, page 37-44

Select IPSec-Pass-Thru Map, page 37-45

IPSec Pass Through Inspect Map, page 37-45

Add/Edit IPSec Pass Thru Policy Map (Security Level), page 37-46

Add/Edit IPSec Pass Thru Policy Map (Details), page 37-47

IPSec Pass Through Inspection Overview

Internet Protocol Security (IPSec) is a protocol suite for securing IP communications by authenticating and encrypting each IP packet of a data stream. IPSec also includes protocols for establishing mutual authentication between agents at the beginning of the session and negotiation of cryptographic keys to

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be used during the session. IPSec can be used to protect data flows between a pair of hosts (for example, computer users or servers), between a pair of security gateways (such as routers or firewalls), or between a security gateway and a host.

IPSec Pass Through application inspection provides convenient traversal of ESP (IP protocol 50) and

AH (IP protocol 51) traffic associated with an IKE UDP port 500 connection. It avoids lengthy access list configuration to permit ESP and AH traffic and also provides security using timeout and max connections.

Specify IPSec Pass Through inspection parameters to identify a specific map to use for defining the parameters for the inspection. Configure a policy map for Specify IPSec Pass Through inspection to access the parameters configuration, which lets you specify the restrictions for ESP or AH traffic. You can set the per client max connections and the idle timeout in parameters configuration.

NAT and non-NAT traffic is permitted. However, PAT is not supported.

Select IPSec-Pass-Thru Map

The Select IPSec-Pass-Thru Map dialog box is accessible as follows:


Select IPSec-Pass-Thru Map

The Select IPSec-Pass-Thru dialog box lets you select or create a new IPSec map. An IPSec map lets you change the configuration values used for IPSec application inspection. The Select IPSec Map table provides a list of previously configured maps that you can select for application inspection.

Fields

•

Use the default IPSec inspection map—Specifies to use the default IPSec map.

•

•

Select an IPSec map for fine control over inspection

—



Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

IPSec Pass Through Inspect Map

The IPSec Pass Through Inspect Map dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > IPSec Pass Through

The IPSec Pass Through pane lets you view previously configured IPSec Pass Through application inspection maps. An IPSec Pass Through map lets you change the default configuration values used for

IPSec Pass Through application inspection. You can use an IPSec Pass Through map to permit certain flows without using an access list.

OL-20339-01


37-45



Fields

•

IPSec Pass Through Inspect Maps—Table that lists the defined IPSec Pass Through inspect maps.

•

Add—Configures a new IPSec Pass Through inspect map. To edit an IPSec Pass Through inspect map, select the IPSec Pass Through entry in the IPSec Pass Through Inspect Maps table and click

Customize.

•

•

Delete—Deletes the inspect map selected in the IPSec Pass Through Inspect Maps table.

Security Level—Select the security level (high or low).

–

Low—Default.

Maximum ESP flows per client: Unlimited.

–

ESP idle timeout: 00:10:00.

Maximum AH flows per client: Unlimited.

AH idle timeout: 00:10:00.

High

Maximum ESP flows per client:10.


Maximum AH flows per client: 10.


–

–

Customize—Opens the Add/Edit IPSec Pass Thru Policy Map dialog box for additional settings.


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit IPSec Pass Thru Policy Map (Security Level)

The Add/Edit IPSec Pass Thru Policy Map (Security Level) dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > IPSec Pass Through>

IPSec Pass Through Inspect Map > Basic View

The Add/Edit IPSec Pass Thru Policy Map pane lets you configure the security level and additional settings for IPSec Pass Thru application inspection maps.

Fields

•

Name—When adding an IPSec Pass Thru map, enter the name of the IPSec Pass Thru map. When editing an IPSec Pass Thru map, the name of the previously configured IPSec Pass Thru map is shown.

•


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•

–

–

Low—Default.

Maximum ESP flows per client: Unlimited.


Maximum AH flows per client: Unlimited.


High

Maximum ESP flows per client:10.

–


Maximum AH flows per client: 10.



Details—Shows additional parameter settings to configure.

Mode


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit IPSec Pass Thru Policy Map (Details)

The Add/Edit IPSec Pass Thru Policy Map (Details) dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps >IPSec Pass Through >

IPSec Pass Through Inspect Map > Advanced View

The Add/Edit IPSec Pass Thru Policy Map pane lets you configure the security level and additional settings for IPSec Pass Thru application inspection maps.

Fields

•

Name—When adding an IPSec Pass Thru map, enter the name of the IPSec Pass Thru map. When editing an IPSec Pass Thru map, the name of the previously configured IPSec Pass Thru map is shown.

•

Description—Enter the description of the IPSec Pass Through map, up to 200 characters in length.

•

•

Security Level—Shows the security level settings to configure.

Parameters—Configures ESP and AH parameter settings.

–

Limit ESP flows per client—Limits ESP flows per client.

Maximum—Specify maximum limit.

–

Apply ESP idle timeout—Applies ESP idle timeout.

Timeout—Specify timeout.

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NetBIOS Inspection


–

Limit AH flows per client—Limits AH flows per client.

–

Maximum—Specify maximum limit.

Apply AH idle timeout—Applies AH idle timeout.

Timeout—Specify timeout.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—



•

NetBIOS Inspection Overview, page 37-48

•

•

•

Select NETBIOS Map, page 37-48

“NetBIOS Inspect Map” section on page 37-49

“Add/Edit NetBIOS Policy Map” section on page 37-49

NetBIOS Inspection Overview

NetBIOS inspection is enabled by default. The NetBios inspection engine translates IP addresses in the

NetBios name service (NBNS) packets according to the adaptive security appliance NAT configuration.

Select NETBIOS Map

The Select NETBIOS Map dialog box is accessible as follows:


Select NetBIOS Map

The Select NETBIOS Map dialog box lets you select or create a new NetBIOS map. A NetBIOS map lets you change the configuration values used for NetBIOS application inspection. The Select NetBIOS

Map table provides a list of previously configured maps that you can select for application inspection.

Fields

•

Use the default IM inspection map—Specifies to use the default NetBIOS map.

•

•

Select a NetBIOS map for fine control over inspection

—



37-48


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Modes


Firewall Mode

Routed


Multiple


• • • •

System

—


NetBIOS Inspect Map

The NetBIOS Inspect Map dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > NetBIOS

The NetBIOS pane lets you view previously configured NetBIOS application inspection maps. A

NetBIOS map lets you change the default configuration values used for NetBIOS application inspection.

NetBIOS application inspection performs NAT for the embedded IP address in the NetBIOS name service packets and NetBIOS datagram services packets. It also enforces protocol conformance, checking the various count and length fields for consistency.

Fields

•

NetBIOS Inspect Maps—Table that lists the defined NetBIOS inspect maps.

•

•

•

Add—Configures a new NetBIOS inspect map.

Edit—Edits the selected NetBIOS entry in the NetBIOS Inspect Maps table.

Delete—Deletes the inspect map selected in the NetBIOS Inspect Maps table.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit NetBIOS Policy Map

The Add/Edit NetBIOS Policy Map dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > NetBIOS > NetBIOS Inspect Map > View

The Add/Edit NetBIOS Policy Map pane lets you configure the protocol violation settings for NetBIOS application inspection maps.

Fields

•

Name—When adding a NetBIOS map, enter the name of the NetBIOS map. When editing an

NetBIOS map, the name of the previously configured NetBIOS map is shown.

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PPTP Inspection


•

•

Description—Enter the description of the NetBIOS map, up to 200 characters in length.

Check for protocol violations—Checks for protocol violations and executes specified action.

–

Action—Drop packet or log.

–


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

PPTP Inspection

PPTP is a protocol for tunneling PPP traffic. A PPTP session is composed of one TCP channel and usually two PPTP GRE tunnels. The TCP channel is the control channel used for negotiating and managing the PPTP GRE tunnels. The GRE tunnels carries PPP sessions between the two hosts.

When enabled, PPTP application inspection inspects PPTP protocol packets and dynamically creates the

GRE connections and xlates necessary to permit PPTP traffic. Only Version 1, as defined in RFC 2637, is supported.

PAT is only performed for the modified version of GRE

[

RFC 2637

]

when negotiated over the PPTP TCP control channel. Port Address Translation is

not

performed for the unmodified version of GRE

[

RFC

1701, RFC 1702

]

.

Specifically, the adaptive security appliance inspects the PPTP version announcements and the outgoing call request/response sequence. Only PPTP Version 1, as defined in RFC 2637, is inspected. Further inspection on the TCP control channel is disabled if the version announced by either side is not Version

1. In addition, the outgoing-call request and reply sequence are tracked. Connections and xlates are dynamic allocated as necessary to permit subsequent secondary GRE data traffic.

The PPTP inspection engine must be enabled for PPTP traffic to be translated by PAT. Additionally, PAT is only performed for a modified version of GRE (RFC2637) and only if it is negotiated over the PPTP

TCP control channel. PAT is not performed for the unmodified version of GRE (RFC 1701 and

RFC 1702).

As described in RFC 2637, the PPTP protocol is mainly used for the tunneling of PPP sessions initiated from a modem bank PAC (PPTP Access Concentrator) to the headend PNS (PPTP Network Server).

When used this way, the PAC is the remote client and the PNS is the server.

However, when used for VPN by Windows, the interaction is inverted. The PNS is a remote single-user

PC that initiates connection to the head-end PAC to gain access to a central network.

SMTP and Extended SMTP Inspection


•

SMTP and ESMTP Inspection Overview, page 37-51

37-50


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•

•

•

•

•

•

Select ESMTP Map, page 37-52

ESMTP Inspect Map, page 37-52

MIME File Type Filtering, page 37-54

Add/Edit ESMTP Policy Map (Security Level), page 37-54

Add/Edit ESMTP Policy Map (Details), page 37-56

Add/Edit ESMTP Inspect, page 37-57


SMTP and ESMTP Inspection Overview

ESMTP application inspection provides improved protection against SMTP-based attacks by restricting the types of SMTP commands that can pass through the adaptive security appliance and by adding monitoring capabilities.

ESMTP is an enhancement to the SMTP protocol and is similar is most respects to SMTP. For convenience, the term SMTP is used in this document to refer to both SMTP and ESMTP. The application inspection process for extended SMTP is similar to SMTP application inspection and includes support for SMTP sessions. Most commands used in an extended SMTP session are the same as those used in an SMTP session but an ESMTP session is considerably faster and offers more options related to reliability and security, such as delivery status notification.

Extended SMTP application inspection adds support for these extended SMTP commands, including

AUTH, EHLO, ETRN, HELP, SAML, SEND, SOML, STARTLS , and VRFY . Along with the support for seven RFC 821 commands (DATA, HELO, MAIL, NOOP, QUIT, RCPT, RSET), the adaptive security appliance supports a total of fifteen SMTP commands.

Other extended SMTP commands, such as ATRN , ONEX , VERB , CHUNKING , and private extensions and are not supported. Unsupported commands are translated into Xs, which are rejected by the internal server. This results in a message such as “500 Command unknown: 'XXX'.” Incomplete commands are discarded.

The ESMTP inspection engine changes the characters in the server SMTP banner to asterisks except for the “2”, “0”, “0” characters. Carriage return (CR) and linefeed (LF) characters are ignored.

With SMTP inspection enabled, a Telnet session used for interactive SMTP may hang if the following rules are not observed: SMTP commands must be at least four characters in length; must be terminated with carriage return and line feed; and must wait for a response before issuing the next reply.

An SMTP server responds to client requests with numeric reply codes and optional human-readable strings. SMTP application inspection controls and reduces the commands that the user can use as well as the messages that the server returns. SMTP inspection performs three primary tasks:

•

•

Restricts SMTP requests to seven basic SMTP commands and eight extended commands.

Monitors the SMTP command-response sequence.

•

Generates an audit trail—Audit record 108002 is generated when invalid character embedded in

t he mail address is replaced. For more information, see RFC 821.

SMTP inspection monitors the command and response sequence for the following anomalous signatures:

•

•

Truncated commands.

Incorrect command termination (not terminated with <CR><LR>).

OL-20339-01


37-51



•

•

•

•

•

The MAIL and RCPT commands specify who are the sender and the receiver of the mail. Mail addresses are scanned for strange characters. The pipeline character (|) is deleted (changed to a blank space) and “<” ‚”>” are only allowed if they are used to define a mail address (“>” must be preceded by “<”).

Unexpected transition by the SMTP server.

For unknown commands, the adaptive security appliance changes all the characters in the packet to

X. In this case, the server generates an error code to the client. Because of the change in the packed, the TCP checksum has to be recalculated or adjusted.

TCP stream editing.

Command pipelining.

Select ESMTP Map

The Select ESMTP Map dialog box is accessible as follows:

Add/Edit Service Policy Rule Wizard > Rule Actions >

Protocol Inspection Tab >Select ESMTP Map

The Select ESMTP Map dialog box lets you select or create a new ESMTP map. An ESMTP map lets you change the configuration values used for ESMTP application inspection. The Select ESMTP Map table provides a list of previously configured maps that you can select for application inspection.

Fields

•

Use the default ESMTP inspection map—Specifies to use the default ESMTP map.

•

Select an ESMTP map for fine control over inspection

—


•


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

ESMTP Inspect Map

The ESMTP Inspect Map dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > ESMTP

The ESMTP pane lets you view previously configured ESMTP application inspection maps. An ESMTP map lets you change the default configuration values used for ESMTP application inspection.

37-52


OL-20339-01



Since ESMTP traffic can be a main source of attack from spam, phising, malformed messages, buffer overflows, and buffer underflows, detailed packet inspection and control of ESMTP traffic are supported. Application security and protocol conformance enforce the sanity of the ESMTP message as well as detect several attacks, block senders and receivers, and block mail relay.

Fields

•

ESMTP Inspect Maps—Table that lists the defined ESMTP inspect maps.

•

•

•

Add—Configures a new ESMTP inspect map. To edit an ESMTP inspect map, choose the ESMTP entry in the ESMTP Inspect Maps table and click

Customize

.

Delete—Deletes the inspect map selected in the ESMTP Inspect Maps table.


–

Low—Default.

Log if command line length is greater than 512

Log if command recipient count is greater than 100

–

Log if body line length is greater than 1000

Log if sender address length is greater than 320

Log if MIME file name length is greater than 255

Medium

Obfuscate Server Banner

Drop Connections if command line length is greater than 512

Drop Connections if command recipient count is greater than 100

Drop Connections if body line length is greater than 1000

–

–

–

–

Drop Connections if sender address length is greater than 320

Drop Connections if MIME file name length is greater than 255

High





Drop Connections and log if sender address length is greater than 320

Drop Connections and log if MIME file name length is greater than 255

MIME File Type Filtering—Opens the MIME Type Filtering dialog box to configure MIME file type filters.

Customize—Opens the Add/Edit ESMTP Policy Map dialog box for additional settings.


Modes


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37-53



Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

MIME File Type Filtering

The MIME File Type Filtering dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > ESMTP > MIME File Type Filtering

The MIME File Type Filtering dialog box lets you configure the settings for a MIME file type filter.

•

•

•

Fields

•


•

•



•

•



Add—Opens the Add MIME File Type Filter dialog box to add a MIME file type filter.

Edit—Opens the Edit MIME File Type Filter dialog box to edit a MIME file type filter.

•

•

Delete—Deletes a MIME file type filter.



Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit ESMTP Policy Map (Security Level)

The Add/Edit ESMTP Policy Map (Security Level) dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > ESMTP > ESMTP Inspect Map > Basic View

The Add/Edit ESMTP Policy Map pane lets you configure the security level and additional settings for

ESMTP application inspection maps.

37-54


OL-20339-01



Fields

•

Name—When adding an ESMTP map, enter the name of the ESMTP map. When editing an ESMTP map, the name of the previously configured ESMTPS map is shown.

•

Description—Enter the description of the ESMTP map, up to 200 characters in length.

•


–

Low—Default.

Log if command line length is greater than 512

Log if command recipient count is greater than 100

–

Log if body line length is greater than 1000

Log if sender address length is greater than 320

Log if MIME file name length is greater than 255

Medium





•

–

Drop Connections if sender address length is greater than 320

Drop Connections if MIME file name length is greater than 255

High





Drop Connections and log if sender address length is greater than 320

–

Drop Connections and log if MIME file name length is greater than 255

MIME File Type Filtering—Opens the MIME Type Filtering dialog box to configure MIME file type filters.

–



Modes


Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

OL-20339-01


37-55



Add/Edit ESMTP Policy Map (Details)

The Add/Edit ESMTP Policy Map (Details) dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > ESMTP > ESMTP Inspect Map > Advanced

View

The Add/Edit ESMTP Policy Map pane lets you configure the security level and additional settings for

ESMTP application inspection maps.

Fields

•

Name—When adding an ESMTP map, enter the name of the ESMTP map. When editing an ESMTP map, the name of the previously configured ESMTP map is shown.

•

Description—Enter the description of the ESMTP map, up to 200 characters in length.

•

•

Security Level—Shows the security level and mime file type filtering settings to configure.

Parameters—Tab that lets you configure the parameters for the ESMTP inspect map.

–

–

Mask server banner—Enforces banner obfuscation.

Configure Mail Relay—Enables ESMTP mail relay.

•

Domain Name—Specifies a local domain.

Action—Drop connection or log.


Inspections—Tab that shows you the ESMTP inspection configuration and lets you add or edit.

–

–


Criterion—Shows the criterion of the ESMTP inspection.

–

–

Value—Shows the value to match in the ESMTP inspection.


–

–


Add—Opens the Add ESMTP Inspect dialog box to add an ESMTP inspection.

–

–

Edit—Opens the Edit ESMTP Inspect dialog box to edit an ESMTP inspection.

Delete—Deletes an ESMTP inspection.

–

–



Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

37-56


OL-20339-01



Add/Edit ESMTP Inspect

The Add/Edit ESMTP Inspect dialog box is accessible as follows:

Configuration > Global Objects > Inspect Maps > ESMTP > ESMTP Inspect Map > Advanced

View > Add/Edit ESMTP Inspect

The Add/Edit ESMTP Inspect dialog box lets you define the match criterion and value for the ESMTP inspect map.

Fields

•




•

Criterion—Specifies which criterion of ESMTP traffic to match.

–

Body Length—Match body length at specified length in bytes.

–

–

Body Line Length—Match body line length matching at specified length in bytes.

Commands—Match commands exchanged in the ESMTP protocol.

–

–

–

–

–

–

–

–

Command Recipient Count—Match command recipient count greater than number specified.

Command Line Length—Match command line length greater than length specified in bytes.

EHLO Reply Parameters—Match an ESMTP ehlo reply parameter.

Header Length—Match header length at length specified in bytes.

Header To Fields Count—Match header To fields count greater than number specified.

Invalid Recipients Count—Match invalid recipients count greater than number specified.

MIME File Type—Match MIME file type.

MIME Filename Length—Match MIME filename.

•

•

•

–

–

MIME Encoding—Match MIME encoding.

Sender Address—Match sender email address.

–

Sender Address Length—Match sender email address length.

Body Length Criterion Values—Specifies the value details for body length match.

–

–

Greater Than Length—Body length in bytes.

Action—Reset, drop connection, log.

–


Body Line Length Criterion Values—Specifies the value details for body line length match.

–

–

Greater Than Length—Body line length in bytes.


–


Commands Criterion Values—Specifies the value details for command match.

–

Available Commands Table:

AUTH

DATA

OL-20339-01


37-57



•

•

•

EHLO

ETRN

HELO

HELP

MAIL

NOOP

QUIT

RCPT

RSET

SAML

SOML

–

VRFY

Add—Adds the selected command from the Available Commands table to the Selected

Commands table.

–

–

Remove—Removes the selected command from the Selected Commands table.

Primary Action—Mask, Reset, Drop Connection, None, Limit Rate (pps).

–

–


Rate Limit—Do not limit rate, Limit Rate (pps).

Command Recipient Count Criterion Values—Specifies the value details for command recipient count match.

–

Greater Than Count—Specify command recipient count.

–

–



Command Line Length Criterion Values—Specifies the value details for command line length.

–

Greater Than Length—Command line length in bytes.

–

–



EHLO Reply Parameters Criterion Values—Specifies the value details for EHLO reply parameters match.

–

Available Parameters Table:

8bitmime auth binarymime checkpoint dsn ecode etrn others

37-58


OL-20339-01



•

•

•

•

•

•

–

–

pipelining size vrfy

Add—Adds the selected parameter from the Available Parameters table to the Selected

Parameters table.


–

–

–

Action—Reset, Drop Connection, Mask, Log.


Header Length Criterion Values—Specifies the value details for header length match.

–

Greater Than Length—Header length in bytes.

–

Action—Reset, Drop Connection, Mask, Log.


Header To Fields Count Criterion Values—Specifies the value details for header To fields count match.

–


–

–



Invalid Recipients Count Criterion Values—Specifies the value details for invalid recipients count match.

–


–

–

MIME File Type Criterion Values—Specifies the value details for MIME file type match.

–


–



–



–

–



–


MIME Filename Length Criterion Values—Specifies the value details for MIME filename length match.

–

–

Greater Than Length—MIME filename length in bytes.

Action—Reset, Drop Connection, Log.

–


MIME Encoding Criterion Values—Specifies the value details for MIME encoding match.

–

Available Encodings table

7bit

OL-20339-01


37-59

TFTP Inspection


•

•

8bit base64 binary

–

–

others quoted-printable

Add—Adds the selected parameter from the Available Encodings table to the Selected

Encodings table.


–

–



Sender Address Criterion Values—Specifies the value details for sender address match.

–


–

–



–

–



–


Sender Address Length Criterion Values—Specifies the value details for sender address length match.

–

–

Greater Than Length—Sender address length in bytes.


–


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

TFTP Inspection

TFTP inspection is enabled by default.

TFTP, described in RFC 1350, is a simple protocol to read and write files between a TFTP server and client.

37-60


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TFTP Inspection

The adaptive security appliance inspects TFTP traffic and dynamically creates connections and translations, if necessary, to permit file transfer between a TFTP client and server. Specifically, the inspection engine inspects TFTP read request (RRQ), write request (WRQ), and error notification

(ERROR).

A dynamic secondary channel and a PAT translation, if necessary, are allocated on a reception of a valid read (RRQ) or write (WRQ) request. This secondary channel is subsequently used by TFTP for file transfer or error notification.

Only the TFTP server can initiate traffic over the secondary channel, and at most one incomplete secondary channel can exist between the TFTP client and server. An error notification from the server closes the secondary channel.

TFTP inspection must be enabled if static PAT is used to redirect TFTP traffic.

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TFTP Inspection


37-62


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C H A P T E R

38

Configuring Inspection for Voice and Video

Protocols



•

CTIQBE Inspection, page 38-1

•

•

•

•

•

H.323 Inspection, page 38-2

MGCP Inspection, page 38-13

RTSP Inspection, page 38-19

SIP Inspection, page 38-23

Skinny (SCCP) Inspection, page 38-36

CTIQBE Inspection

This section describes CTIQBE application inspection. This section includes the following topics:

•

CTIQBE Inspection Overview, page 38-1

•

Limitations and Restrictions, page 38-2

CTIQBE Inspection Overview

CTIQBE protocol inspection supports NAT, PAT, and bidirectional NAT. This enables Cisco IP

SoftPhone and other Cisco TAPI/JTAPI applications to work successfully with Cisco CallManager for call setup across the adaptive security appliance.

TAPI and JTAPI are used by many Cisco VoIP applications. CTIQBE is used by Cisco TSP to communicate with Cisco CallManager.


38-1 OL-20339-01

Chapter 38 Configuring Inspection for Voice and Video Protocols

H.323 Inspection


The following summarizes limitations that apply when using CTIQBE application inspection:

•

CTIQBE application inspection does not support configurations with the

alias

command.

•

•

Stateful failover of CTIQBE calls is not supported.

Debugging CTIQBE inspection may delay message transmission, which may have a performance impact in a real-time environment. When you enable this debugging or logging and

Cisco IP SoftPhone seems unable to complete call setup through the adaptive security appliance, increase the timeout values in the Cisco TSP settings on the system running Cisco IP SoftPhone.

The following summarizes special considerations when using CTIQBE application inspection in specific scenarios:

•

If two Cisco IP SoftPhones are registered with different Cisco CallManagers, which are connected to different interfaces of the adaptive security appliance, calls between these two phones fails.

•

•

When Cisco CallManager is located on the higher security interface compared to

Cisco IP SoftPhones, if NAT or outside NAT is required for the Cisco CallManager IP address, the mapping must be static as Cisco IP SoftPhone requires the Cisco CallManager IP address to be specified explicitly in its Cisco TSP configuration on the PC.

When using PAT or Outside PAT, if the Cisco CallManager IP address is to be translated, its TCP port 2748 must be statically mapped to the same port of the PAT (interface) address for Cisco IP

SoftPhone registrations to succeed. The CTIQBE listening port (TCP 2748) is fixed and is not user-configurable on Cisco CallManager, Cisco IP SoftPhone, or Cisco TSP.


This section describes the H.323 application inspection. This section includes the following topics:

•

•

•

•

•

•

•

•

•

•

•

•

•

•

H.323 Inspection Overview, page 38-3

How H.323 Works, page 38-3

H.239 Support in H.245 Messages, page 38-4

Limitations and Restrictions, page 38-4

Select H.323 Map, page 38-5

H.323 Class Map, page 38-5

Add/Edit H.323 Traffic Class Map, page 38-6

Add/Edit H.323 Match Criterion, page 38-6

H.323 Inspect Map, page 38-7

Phone Number Filtering, page 38-9

Add/Edit H.323 Policy Map (Security Level), page 38-9

Add/Edit H.323 Policy Map (Details), page 38-10

Add/Edit HSI Group, page 38-12

Add/Edit H.323 Map, page 38-12

38-2


OL-20339-01



H.323 Inspection Overview

H.323 inspection provides support for H.323 compliant applications such as Cisco CallManager and

VocalTec Gatekeeper. H.323 is a suite of protocols defined by the International Telecommunication

Union for multimedia conferences over LANs. The adaptive security appliance supports H.323 through

Version 6, including H.323 v3 feature Multiple Calls on One Call Signaling Channel.

With H.323 inspection enabled, the adaptive security appliance supports multiple calls on the same call signaling channel, a feature introduced with H.323 Version 3. This feature reduces call setup time and reduces the use of ports on the adaptive security appliance.

The two major functions of H.323 inspection are as follows:

•

NAT the necessary embedded IPv4 addresses in the H.225 and H.245 messages. Because H.323 messages are encoded in PER encoding format, the adaptive security appliance uses an ASN.1 decoder to decode the H.323 messages.

•

Dynamically allocate the negotiated H.245 and RTP/RTCP connections.

How H.323 Works

The H.323 collection of protocols collectively may use up to two TCP connection and four to eight UDP connections. FastConnect uses only one TCP connection, and RAS uses a single UDP connection for registration, admissions, and status.

An H.323 client can initially establish a TCP connection to an H.323 server using TCP port 1720 to request Q.931 call setup. As part of the call setup process, the H.323 terminal supplies a port number to the client to use for an H.245 TCP connection. In environments where H.323 gatekeeper is in use, the initial packet is transmitted using UDP.

H.323 inspection monitors the Q.931 TCP connection to determine the H.245 port number. If the H.323 terminals are not using FastConnect, the adaptive security appliance dynamically allocates the H.245 connection based on the inspection of the H.225 messages.

Note

The H.225 connection can also be dynamically allocated when using RAS.

Within each H.245 message, the H.323 endpoints exchange port numbers that are used for subsequent

UDP data streams. H.323 inspection inspects the H.245 messages to identify these ports and dynamically creates connections for the media exchange. RTP uses the negotiated port number, while RTCP uses the next higher port number.

The H.323 control channel handles H.225 and H.245 and H.323 RAS. H.323 inspection uses the following ports.

•

1718—Gate Keeper Discovery UDP port

•

•

1719—RAS UDP port

1720—TCP Control Port

You must permit traffic for the well-known H.323 port 1719 for RAS signaling. Additionally, you must permit traffic for the well-known H.323 port 1720 for the H.225 call signaling; however, the H.245 signaling ports are negotiated between the endpoints in the H.225 signaling. When an H.323 gatekeeper is used, the adaptive security appliance opens an H.225 connection based on inspection of the ACF and

RCF nmessages.

OL-20339-01


38-3



After inspecting the H.225 messages, the adaptive security appliance opens the H.245 channel and then inspects traffic sent over the H.245 channel as well. All H.245 messages passing through the adaptive security appliance undergo H.245 application inspection, which translates embedded IP addresses and opens the media channels negotiated in H.245 messages.

The H.323 ITU standard requires that a TPKT header, defining the length of the message, precede the

H.225 and H.245, before being passed on to the reliable connection. Because the TPKT header does not necessarily need to be sent in the same TCP packet as H.225 and H.245 messages, the adaptive security appliance must remember the TPKT length to process and decode the messages properly. For each connection, the adaptive security appliance keeps a record that contains the TPKT length for the next expected message.

If the adaptive security appliance needs to perform NAT on IP addresses in messages, it changes the checksum, the UUIE length, and the TPKT, if it is included in the TCP packet with the H.225 message.

If the TPKT is sent in a separate TCP packet, the adaptive security appliance proxy ACKs that TPKT and appends a new TPKT to the H.245 message with the new length.

Note

The adaptive security appliance does not support TCP options in the Proxy ACK for the TPKT.

Each UDP connection with a packet going through H.323 inspection is marked as an H.323 connection and times out with the H.323 timeout as configured in the Configuration > Firewall > Advanced > Global

Timeouts pane.

Note

You can enable call setup between H.323 endpoints when the Gatekeeper is inside the network. The adaptive security appliance includes options to open pinholes for calls based on the

RegistrationRequest/RegistrationConfirm (RRQ/RCF) messages. Because these RRQ/RCF messages are sent to and from the Gatekeeper, the calling endpoint's IP address is unknown and the adaptive security appliance opens a pinhole through source IP address/port 0/0. By default, this option is disabled.

H.239 Support in H.245 Messages

The adaptive security appliance sits between two H.323 endpoints. When the two H.323 endpoints set up a telepresentation session so that the endpoints can send and receive a data presentation, such as spreadsheet data, the adaptive security appliance ensure successful H.239 negotiation between the endpoints.

H.239 is a standar that provides the ability for H.300 series endpoints to open an additional video channel in a single call. In a call, an endpoint (such as a video phone), sends a channel for video and a channel for data presentation. The H.239 negotiation occurs on the H.245 channel.

The adaptive security appliance opens pinholes for the additional media channel and the media control channel. The endpoints use open logical channel message (OLC) to signal a new channel creation. The message extension is part of H.245 version 13.

The decoding and encoding of of the telepresentation session is enabled by default. H.239 encoding and decoding is preformed by ASN.1 coder.


The following are some of the known issues and limitations when using H.323 application inspection:

38-4


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•

•

•

•

Static PAT may not properly translate IP addresses embedded in optional fields within H.323 messages. If you experience this kind of problem, do not use static PAT with H.323.

H.323 application inspection is not supported with NAT between same-security-level interfaces.

When a NetMeeting client registers with an H.323 gatekeeper and tries to call an H.323 gateway that is also registered with the H.323 gatekeeper, the connection is established but no voice is heard in either direction. This problem is unrelated to the adaptive security appliance.

If you configure a network static address where the network static address is the same as a third-party netmask and address, then any outbound H.323 connection fails.

Select H.323 Map

The Select H.323 Map dialog box lets you select or create a new H.323 map. An H.323 map lets you change the configuration values used for H.323 application inspection. The Select H.323 Map table provides a list of previously configured maps that you can select for application inspection.

Fields

•

Use the default H.323 inspection map—Specifies to use the default H.323 map.

•

•

Select an H.323 map for fine control over inspection

—



Modes


Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

H.323 Class Map

The H.323 Class Map pane lets you configure H.323 class maps for H.323 inspection.



Fields

•

Name—Shows the H.323 class map name.

•


–

–


Criterion—Shows the criterion of the H.323 class map.

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38-5



•

•

•

•

–

Value—Shows the value to match in the H.323 class map.


Add—Adds an H.323 class map.

Edit—Edits an H.323 class map.

Delete—Deletes an H.323 class map.

Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

Add/Edit H.323 Traffic Class Map

The Add/Edit H.323 Traffic Class Map dialog box lets you define a H.323 class map.

Fields

•

Name—Enter the name of the H.323 class map, up to 40 characters in length.

•

•

•

•

Description—Enter the description of the H.323 class map.

Add—Adds an H.323 class map.

Edit—Edits an H.323 class map.

Delete—Deletes an H.323 class map.

Modes


Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

Add/Edit H.323 Match Criterion

The Add/Edit H.323 Match Criterion dialog box lets you define the match criterion and value for the

H.323 class map.

Fields

•


38-6


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•

•

•

•



Criterion—Specifies which criterion of H.323 traffic to match.

–

Called Party—Match the called party.

–

–

Calling Party—Match the calling party.

Media Type—Match the media type.

Called Party Criterion Values—Specifies to match on the H.323 called party.

–


–

–



–


Calling Party Criterion Values—Specifies to match on the H.323 calling party.

–

–



–

–



Media Type Criterion Values—Specifies which media type to match.

–

Audio—Match audio type.

–

–

Video—Match video type.

Data—Match data type.

Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

H.323 Inspect Map

The H.323 pane lets you view previously configured H.323 application inspection maps. An H.323 map lets you change the default configuration values used for H.323 application inspection.

H.323 inspection supports RAS, H.225, and H.245, and its functionality translates all embedded IP addresses and ports. It performs state tracking and filtering and can do a cascade of inspect function activation. H.323 inspection supports phone number filtering, dynamic T.120 control, H.245 tunneling control, HSI groups, protocol state tracking, H.323 call duration enforcement, and audio/video control.

OL-20339-01


38-7



Fields

•

H.323 Inspect Maps—Table that lists the defined H.323 inspect maps.

•

Add—Configures a new H.323 inspect map. To edit an H.323 inspect map, choose the H.323 entry in the H.323 Inspect Maps table and click

Customize

.

•

•

Delete—Deletes the inspect map selected in the H.323 Inspect Maps table.


–

Low—Default.

State Checking h225 Disabled

State Checking ras Disabled

Call Party Number Disabled

Call duration Limit Disabled

RTP conformance not enforced

–

Medium

State Checking h225 Enabled

State Checking ras Enabled



RTP conformance enforced

–

Limit payload to audio or video, based on the signaling exchange: no

High



Call Party Number Enabled

Call duration Limit 1:00:00

–

–


Limit payload to audio or video, based on the signaling exchange: yes

Phone Number Filtering—Opens the Phone Number Filtering dialog box to configure phone number filters.

Customize—Opens the Add/Edit H.323 Policy Map dialog box for additional settings.

–


Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

38-8


OL-20339-01



Phone Number Filtering

The Phone Number Filtering dialog box lets you configure the settings for a phone number filter.

•

•

•

Fields

•


•


•

•

•

•




Add—Opens the Add Phone Number Filter dialog box to add a phone number filter.

•

Edit—Opens the Edit Phone Number Filter dialog box to edit a phone number filter.

Delete—Deletes a phone number filter.



Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit H.323 Policy Map (Security Level)

The Add/Edit H.323 Policy Map pane lets you configure the security level and additional settings for

H.323 application inspection maps.

Fields

•

Name—When adding an H.323 map, enter the name of the H.323 map. When editing an H.323 map, the name of the previously configured H.323 map is shown.

•

•

Description—Enter the description of the H323 map, up to 200 characters in length.


–

Low—Default.

State Checking h225 Disabled

State Checking ras Disabled


–


RTP conformance not enforced

Medium


OL-20339-01 38-9



•




–



Limit payload to audio or video, based on the signaling exchange: no

High



Call Party Number Enabled

Call duration Limit 1:00:00

–

–


Limit payload to audio or video, based on the signaling exchange: yes

Phone Number Filtering—Opens the Phone Number Filtering dialog box which lets you configure the settings for a phone number filter.


Details—Shows the State Checking, Call Attributes, Tunneling and Protocol Conformance, HSI

Group Parameters, and Inspections tabs to configure additional settings.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit H.323 Policy Map (Details)

The Add/Edit H.323 Policy Map pane lets you configure the security level and additional settings for

H.323 application inspection maps.

Fields

•

Name—When adding an H.323 map, enter the name of the H.323 map. When editing an H.323 map, the name of the previously configured H.323 map is shown.

•

Description—Enter the description of the H.323 map, up to 200 characters in length.

•

•

Security Level—Shows the security level and phone number filtering settings to configure.

State Checking—Tab that lets you configure state checking parameters for the H.323 inspect map.

–

–

Check state transition of H.225 messages—Enforces H.323 state checking on H.225 messages.

Check state transition of RAS messages—Enforces H.323 state checking on RAS messages.

38-10


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–

Check RFC messages and open pinholes for call signal addresses in RFQ messages

Note

You can enable call setup between H.323 endpoints when the Gatekeeper is inside the network. The adaptive security appliance includes options to open pinholes for calls based on the RegistrationRequest/RegistrationConfirm (RRQ/RCF) messages. Because these

RRQ/RCF messages are sent to and from the Gatekeeper, the calling endpoint's IP address is unknown and the adaptive security appliance opens a pinhole through source IP address/port 0/0. By default, this option is disabled. You can enable this option by setting the option in the H.323 Inspect Map.

•

•

•

•

Call Attributes—Tab that lets you configure call attributes parameters for the H.323 inspect map.

–

Enforce call duration limit—Enforces the absolute limit on a call.

Call Duration Limit—Time limit for the call (hh:mm:ss).

–

–

Enforce presence of calling and called party numbers—Enforces sending call party numbers during call setup.

Tunneling and Protocol Conformance—Tab that lets you configure tunneling and protocol conformance parameters for the H.323 inspect map.

Check for H.245 tunneling—Allows H.245 tunneling.


–

Check RTP packets for protocol conformance—Checks RTP/RTCP packets on the pinholes for protocol conformance.

Limit payload to audio or video, based on the signaling exchange—Enforces the payload type to be audio or video based on the signaling exchange.

HSI Group Parameters—Tab that lets you configure an HSI group.

–

HSI Group ID—Shows the HSI Group ID.

–

IP Address—Shows the HSI Group IP address.

–

–

–

–

Delete—Deletes an HSI group.

Inspections—Tab that shows you the H.323 inspection configuration and lets you add or edit.

–

–


Criterion—Shows the criterion of the H.323 inspection.

–

Endpoints—Shows the HSI Group endpoints.

Add—Opens the Add HSI Group dialog box to add an HSI group.

Edit—Opens the Edit HSI Group dialog box to edit an HSI group.

–

–

–

Value—Shows the value to match in the H.323 inspection.



Add—Opens the Add H.323 Inspect dialog box to add an H.323 inspection.

–

–

–

–

Edit—Opens the Edit H.323 Inspect dialog box to edit an H.323 inspection.

Delete—Deletes an H.323 inspection.



OL-20339-01


38-11



Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit HSI Group

The Add/Edit HSI Group dialog box lets you configure HSI Groups.

Fields

•

Group ID—Enter the HSI group ID.

•

IP Address—Enter the HSI IP address.

•

•

•

Endpoints—Lets you configure the IP address and interface of the endpoints.

–

IP Address—Enter an endpoint IP address.

–

Interface—Specifies an endpoint interface.

Add—Adds the HSI group defined.

Delete—Deletes the selected HSI group.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit H.323 Map

The Add/Edit H.323 Inspect dialog box lets you define the match criterion and value for the H.323 inspect map.

Fields

•

Single Match—Specifies that the H.323 inspect has only one match statement.

•


•



Criterion—Specifies which criterion of H.323 traffic to match.

–

Called Party—Match the called party.

38-12


OL-20339-01


MGCP Inspection

•

•

•

•

•

–

Calling Party—Match the calling party.

–

Media Type—Match the media type.

Called Party Criterion Values—Specifies to match on the H.323 called party.

–

–



–

–



Calling Party Criterion Values—Specifies to match on the H.323 calling party.

–


–

–



–


Media Type Criterion Values—Specifies which media type to match.

–

–

–

Data—Match data type.

Multiple Matches—Specifies multiple matches for the H.323 inspection.

–

Audio—Match audio type.

Video—Match video type.

–

H323 Traffic Class—Specifies the H.323 traffic class match.

Manage—Opens the Manage H323 Class Maps dialog box to add, edit, or delete H.323 Class

Maps.

Action—Drop packet, drop connection, or reset.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

MGCP Inspection

This section describes MGCP application inspection. This section includes the following topics:

•

MGCP Inspection Overview, page 38-14

•

•

Select MGCP Map, page 38-16

MGCP Inspect Map, page 38-16

OL-20339-01


38-13


MGCP Inspection

•

•

•

Gateways and Call Agents, page 38-17

Add/Edit MGCP Policy Map, page 38-17

Add/Edit MGCP Group, page 38-18

MGCP Inspection Overview

MGCP is a master/slave protocol used to control media gateways from external call control elements called media gateway controllers or call agents. A media gateway is typically a network element that provides conversion between the audio signals carried on telephone circuits and data packets carried over the Internet or over other packet networks. Using NAT and PAT with MGCP lets you support a large number of devices on an internal network with a limited set of external (global) addresses. Examples of media gateways are:

•

Trunking gateways, that interface between the telephone network and a Voice over IP network. Such gateways typically manage a large number of digital circuits.

•

•

Residential gateways, that provide a traditional analog (RJ11) interface to a Voice over IP network.

Examples of residential gateways include cable modem/cable set-top boxes, xDSL devices, broad-band wireless devices.

Business gateways, that provide a traditional digital PBX interface or an integrated soft PBX interface to a Voice over IP network.

Note

To avoid policy failure when upgrading from ASA version 7.1, all layer 7 and layer 3 policies must have distinct names. For instance, a previously configured policy map with the same name as a previously configured MGCP map must be changed before the upgrade.

MGCP messages are transmitted over UDP. A response is sent back to the source address (IP address and UDP port number) of the command, but the response may not arrive from the same address as the command was sent to. This can happen when multiple call agents are being used in a failover configuration and the call agent that received the command has passed control to a backup call agent, which then sends the response.

Figure 38-1

illustrates how NAT can be used with MGCP.

38-14


OL-20339-01


MGCP Inspection

Figure 38-1 Using NAT with MGCP

Cisco

PGW 2200

To PSTN

H.323

M

M

M

Cisco

CallManager

209.165.201.10

209.165.201.11

209.165.201.1

Gateway is told to send its media to 209.165.200.231

(public address of the IP Phone)

MGCP

209.165.200.2

3 1

GW GW

RTP to 209.165.201.1

from 209.165.200.2

3 1

SCCP

209.165.200.2

RTP to 10.0.0.76

from 209.165.200.2

IP IP IP

10.0.0.76

Branch offices

3

3

1

1

MGCP endpoints are physical or virtual sources and destinations for data. Media gateways contain endpoints on which the call agent can create, modify and delete connections to establish and control media sessions with other multimedia endpoints. Also, the call agent can instruct the endpoints to detect certain events and generate signals. The endpoints automatically communicate changes in service state to the call agent.

MGCP transactions are composed of a command and a mandatory response. There are eight types of commands:

•

•

•

•

•

CreateConnection

ModifyConnection

DeleteConnection

NotificationRequest

•

•

•

Notify

AuditEndpoint

AuditConnection

RestartInProgress

The first four commands are sent by the call agent to the gateway. The Notify command is sent by the gateway to the call agent. The gateway may also send a DeleteConnection. The registration of the MGCP gateway with the call agent is achieved by the RestartInProgress command. The AuditEndpoint and the

AuditConnection commands are sent by the call agent to the gateway.

All commands are composed of a Command header, optionally followed by a session description. All responses are composed of a Response header, optionally followed by a session description.

•

The port on which the gateway receives commands from the call agent. Gateways usually listen to

UDP port 2427.

OL-20339-01


38-15

MGCP Inspection


•

The port on which the call agent receives commands from the gateway. Call agents usually listen to

UDP port 2727.

Note

MGCP inspection does not support the use of different IP addresses for MGCP signaling and RTP data.

A common and recommended practice is to send RTP data from a resilient IP address, such as a loopback or virtual IP address; however, the adaptive security appliance requires the RTP data to come from the same address as MGCP signalling.

Select MGCP Map

The Select MGCP Map dialog box lets you select or create a new MGCP map. An MGCP map lets you change the configuration values used for MGCP application inspection. The Select MGCP Map table provides a list of previously configured maps that you can select for application inspection.

Fields

•

Use the default MGCP inspection map—Specifies to use the default MGCP map.

•

Select an MGCP map for fine control over inspection

—


•


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

MGCP Inspect Map

The MGCP pane lets you view previously configured MGCP application inspection maps. An MGCP map lets you change the default configuration values used for MGCP application inspection. You can use an MGCP map to manage connections between VoIP devices and MGCP call agents.

Fields

•

MGCP Inspect Maps—Table that lists the defined MGCP inspect maps.

•

Add—Configures a new MGCP inspect map.

•

•

Edit—Edits the selected MGCP entry in the MGCP Inspect Maps table.

Delete—Deletes the inspect map selected in the MGCP Inspect Maps table.

Modes


38-16


OL-20339-01


MGCP Inspection

Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

Gateways and Call Agents

The Gateways and Call Agents dialog box lets you configure groups of gateways and call agents for the map.

Fields

•

Group ID—Identifies the ID of the call agent group. A call agent group associates one or more call agents with one or more MGCP media gateways. The gateway IP address can only be associated with one group ID. You cannot use the same gateway with different group IDs. The valid range is from 0 to 2147483647Criterion—Shows the criterion of the inspection.

•

•

Gateways—Identifies the IP address of the media gateway that is controlled by the associated call agent. A media gateway is typically a network element that provides conversion between the audio signals carried on telephone circuits and data packets carried over the Internet or over other packet networks. Normally, a gateway sends commands to the default MGCP port for call agents, 2727.

Call Agents—Identifies the IP address of a call agent that controls the MGCP media gateways in the call agent group. Normally, a call agent sends commands to the default MGCP port for gateways,

2427.

•

•

•

Add—Displays the Add MGCP dialog box, which you can use to define a new application inspection map.

Edit—Displays the Edit MGCP dialog box, which you can use to modify the application inspection map selected in the application inspection map table.

Delete—Deletes the application inspection map selected in the application inspection map table.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit MGCP Policy Map

The Add/Edit MGCP Policy Map pane lets you configure the command queue, gateway, and call agent settings for MGCP application inspection maps.

OL-20339-01


38-17

MGCP Inspection


Fields

•

Name—When adding an MGCP map, enter the name of the MGCP map. When editing an MGCP map, the name of the previously configured MGCP map is shown.

•

Description—Enter the description of the MGCP map, up to 200 characters in length.

•

•

Command Queue—Tab that lets you specify the permitted queue size for MGCP commands.

–

Command Queue Size—Specifies the maximum number of commands to queue. The valid range is from 1 to 2147483647.

Gateways and Call Agents—Tab that lets you configure groups of gateways and call agents for this map.

–

Group ID—Identifies the ID of the call agent group. A call agent group associates one or more call agents with one or more MGCP media gateways. The gateway IP address can only be associated with one group ID. You cannot use the same gateway with different group IDs. The valid range is from 0 to 2147483647Criterion—Shows the criterion of the inspection.

–

–

Gateways—Identifies the IP address of the media gateway that is controlled by the associated call agent. A media gateway is typically a network element that provides conversion between the audio signals carried on telephone circuits and data packets carried over the Internet or over other packet networks. Normally, a gateway sends commands to the default MGCP port for call agents, 2727.

Call Agents—Identifies the IP address of a call agent that controls the MGCP media gateways in the call agent group. Normally, a call agent sends commands to the default MGCP port for gateways, 2427.

–

–

Add—Displays the Add MGCP Group dialog box, which you can use to define a new MGCP group of gateways and call agents.

Edit—Displays the Edit MGCP dialog box, which you can use to modify the MGCP group selected in the Gateways and Call Agents table.

–

Delete—Deletes the MGCP group selected in the Gateways and Call Agents table.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit MGCP Group

The Add/Edit MGCP Group dialog box lets you define the configuration of an MGCP group that will be used when MGCP application inspection is enabled.

Fields

•

Group ID—Specifies the ID of the call agent group. A call agent group associates one or more call agents with one or more MGCP media gateways. The valid range is from 0 to 2147483647.

38-18


OL-20339-01


RTSP Inspection

•

–

–

–

–

Gateway to Be Added—Specifies the IP address of the media gateway that is controlled by the associated call agent. A media gateway is typically a network element that provides conversion between the audio signals carried on telephone circuits and data packets carried over the

Internet or over other packet networks. Normally, a gateway sends commands to the default

MGCP port for call agents, 2727.

Add—Adds the specified IP address to the IP address table.

Delete—Deletes the selected IP address from the IP address table.

–

IP Address—Lists the IP addresses of the gateways in the call agent group.

Call Agents

–

–

Call Agent to Be Added—Specifies the IP address of a call agent that controls the MGCP media gateways in the call agent group. Normally, a call agent sends commands to the default MGCP port for gateways, 2427.

Add—Adds the specified IP address to the IP address table.

–

Delete—Deletes the selected IP address from the IP address table.

IP Address—Lists the IP addresses of the call agents in the call agent group.

Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

RTSP Inspection

•

•

•

This section describes RTSP application inspection. This section includes the following topics:

•

•

RTSP Inspection Overview, page 38-19

Using RealPlayer, page 38-20

•

•

Restrictions and Limitations, page 38-20

Select RTSP Map, page 38-21

RTSP Inspect Map, page 38-21

Add/Edit RTSP Policy Map, page 38-22

Add/Edit RTSP Inspect, page 38-22

RTSP Inspection Overview

The RTSP inspection engine lets the adaptive security appliance pass RTSP packets. RTSP is used by

RealAudio, RealNetworks, Apple QuickTime 4, RealPlayer, and Cisco IP/TV connections.

OL-20339-01


38-19


RTSP Inspection

Note

For Cisco IP/TV, use RTSP TCP port 554 and TCP 8554.

RTSP applications use the well-known port 554 with TCP (rarely UDP) as a control channel. The adaptive security appliance only supports TCP, in conformity with RFC 2326. This TCP control channel is used to negotiate the data channels that is used to transmit audio/video traffic, depending on the transport mode that is configured on the client.

The supported RDT transports are: rtp/avp, rtp/avp/udp, x-real-rdt, x-real-rdt/udp, and x-pn-tng/udp.

The adaptive security appliance parses Setup response messages with a status code of 200. If the response message is travelling inbound, the server is outside relative to the adaptive security appliance and dynamic channels need to be opened for connections coming inbound from the server. If the response message is outbound, then the adaptive security appliance does not need to open dynamic channels.

Because RFC 2326 does not require that the client and server ports must be in the SETUP response message, the adaptive security appliance keeps state and remembers the client ports in the SETUP message. QuickTime places the client ports in the SETUP message and then the server responds with only the server ports.

RTSP inspection does not support PAT or dual-NAT. Also, the adaptive security appliance cannot recognize HTTP cloaking where RTSP messages are hidden in the HTTP messages.

Using RealPlayer

When using RealPlayer, it is important to properly configure transport mode. For the adaptive security appliance, add an

access-list

command from the server to the client or vice versa. For RealPlayer, change transport mode by clicking

Options

>

Preferences

>

Transport

>

RTSP Settings

.

If using TCP mode on the RealPlayer, select the

Use TCP to Connect to Server

and

Attempt to use

TCP for all content

check boxes. On the adaptive security appliance, there is no need to configure the inspection engine.

If using UDP mode on the RealPlayer, select the

Use TCP to Connect to Server

and

Attempt to use

UDP for static content

check boxes, and for live content not available via Multicast. On the adaptive security appliance, add an

inspect rtsp

port

command.

Restrictions and Limitations

The following restrictions apply to the RSTP inspection.

•

The adaptive security appliance does not support multicast RTSP or RTSP messages over UDP.

•

•

The adaptive security appliance does not have the ability to recognize HTTP cloaking where RTSP messages are hidden in the HTTP messages.

The adaptive security appliance cannot perform NAT on RTSP messages because the embedded IP addresses are contained in the SDP files as part of HTTP or RTSP messages. Packets could be fragmented and adaptive security appliance cannot perform NAT on fragmented packets.

•

With Cisco IP/TV, the number of translates the adaptive security appliance performs on the SDP part of the message is proportional to the number of program listings in the Content Manager (each program listing can have at least six embedded IP addresses).

38-20


OL-20339-01


RTSP Inspection

•

You can configure NAT for Apple QuickTime 4 or RealPlayer. Cisco IP/TV only works with NAT if the Viewer and Content Manager are on the outside network and the server is on the inside network.

Select RTSP Map

The Select RTSP Map dialog box lets you select or create a new RTSP map. An RTSP map lets you change the configuration values used for RTSP application inspection. The Select RTSP Map table provides a list of previously configured maps that you can select for application inspection.

Fields

•

Use the default RTSP inspection map—Specifies to use the default RTSP inspection map.

•

Select a RTSP inspect map for fine control over inspection

—


•


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

RTSP Inspect Map

The RTSP pane lets you view previously configured RTSP application inspection maps. An RTSP map lets you change the default configuration values used for RTSP application inspection. You can use an

RTSP map to protect RTSP traffic.

Fields

•

RTSP Inspect Maps—Table that lists the defined RTSP inspect maps.

•

Add—Configures a new RTSP inspect map.

•

•

Edit—Edits the selected RTSP entry in the RTSP Inspect Maps table.

Delete—Deletes the inspect map selected in the RTSP Inspect Maps table.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

OL-20339-01


38-21


RTSP Inspection

Add/Edit RTSP Policy Map

The Add/Edit RTSP Policy Map pane lets you configure the parameters and inspections settings for

RTSP application inspection maps.

Fields

•

Name—When adding an RTSP map, enter the name of the RTSP map. When editing an RTSP map, the name of the previously configured RTSP map is shown.

•

Description—Enter the description of the RTSP map, up to 200 characters in length.

•

•

Parameters—Tab that lets you restrict usage on reserved ports during media port negotiation, and lets you set the URL length limit.

–

Enforce Reserve Port Protection—Lets you restrict the use of reserved ports during media port negotiation.

–

Maximum URL Length—Specifies the maximum length of the URL allowed in the message.

Maximum value is 6000.

Inspections—Tab that shows you the RTSP inspection configuration and lets you add or edit.

–

–


Criterion—Shows the criterion of the RTSP inspection.

–

–

Value—Shows the value to match in the RTSP inspection.


–

–


Add—Opens the Add RTSP Inspect dialog box to add a RTSP inspection.

–

–

Edit—Opens the Edit RTSP Inspect dialog box to edit a RTSP inspection.

Delete—Deletes a RTSP inspection.

–

–



Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit RTSP Inspect

The Add/Edit RTSP Inspect dialog box lets you define the match criterion, values, and actions for the

RTSP inspect map.

Fields

•


38-22


OL-20339-01


SIP Inspection

•

•

•

•

•



Criterion—Specifies which criterion of RTSP traffic to match.

–

URL Filter—Match URL filtering.

–

Request Method—Match an RTSP request method.

URL Filter Criterion Values—Specifies to match URL filtering. Applies the regular expression match.

–

–



–

–



URL Filter Actions—Primary action and log settings.

–


–


Request Method Criterion Values—Specifies to match an RTSP request method.

–

Request Method—Specifies a request method: announce, describe, get_parameter, options, pause, play, record, redirect, setup, set_parameters, teardown.

Request Method Actions—Primary action settings.

–

Action—Limit rate (pps).

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

SIP Inspection

•

•

•

This section describes SIP application inspection. This section includes the following topics:

•

SIP Inspection Overview, page 38-24

SIP Instant Messaging, page 38-24

Select SIP Map, page 38-25

•

SIP Class Map, page 38-26

Add/Edit SIP Traffic Class Map, page 38-27

•

•

Add/Edit SIP Match Criterion, page 38-27

SIP Inspect Map, page 38-29

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SIP Inspection


•

•

•

•

Add/Edit SIP Policy Map (Security Level), page 38-31

Add/Edit SIP Policy Map (Details), page 38-32

Add/Edit SIP Inspect, page 38-34

SIP Inspection Overview

SIP, as defined by the IETF, enables call handling sessions, particularly two-party audio conferences, or

“calls.” SIP works with SDP for call signalling. SDP specifies the ports for the media stream. Using SIP, the adaptive security appliance can support any SIP VoIP gateways and VoIP proxy servers. SIP and SDP are defined in the following RFCs:

•

•

SIP: Session Initiation Protocol, RFC 3261

SDP: Session Description Protocol, RFC 2327

To support SIP calls through the adaptive security appliance, signaling messages for the media connection addresses, media ports, and embryonic connections for the media must be inspected, because while the signaling is sent over a well-known destination port (UDP/TCP 5060), the media streams are dynamically allocated. Also, SIP embeds IP addresses in the user-data portion of the IP packet. SIP inspection applies NAT for these embedded IP addresses.

The following limitations and restrictions apply when using PAT with SIP:

•

If a remote endpoint tries to register with a SIP proxy on a network protected by the adaptive security appliance, the registration fails under very specific conditions, as follows:

–

PAT is configured for the remote endpoint.

–

–

The SIP registrar server is on the outside network.

The port is missing in the contact field in the REGISTER message sent by the endpoint to the proxy server.

•

If a SIP device transmits a packet in which the SDP portion has an IP address in the owner/creator field (o=) that is different than the IP address in the connection field (c=), the IP address in the o= field may not be properly translated. This is due to a limitation in the SIP protocol, which does not provide a port value in the o= field.

SIP Instant Messaging

Instant Messaging refers to the transfer of messages between users in near real-time. SIP supports the

Chat feature on Windows XP using Windows Messenger RTC Client version 4.7.0105 only. The

MESSAGE/INFO methods and 202 Accept response are used to support IM as defined in the following

RFCs:

•

•

Session Initiation Protocol (SIP)-Specific Event Notification, RFC 3265

Session Initiation Protocol (SIP) Extension for Instant Messaging, RFC 3428

MESSAGE/INFO requests can come in at any time after registration/subscription. For example, two users can be online at any time, but not chat for hours. Therefore, the SIP inspection engine opens pinholes that time out according to the configured SIP timeout value. This value must be configured at least five minutes longer than the subscription duration. The subscription duration is defined in the

Contact Expires value and is typically 30 minutes.

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SIP Inspection

Because MESSAGE/INFO requests are typically sent using a dynamically allocated port other than port

5060, they are required to go through the SIP inspection engine.

Note

Only the Chat feature is currently supported. Whiteboard, File Transfer, and Application Sharing are not supported. RTC Client 5.0 is not supported.

SIP inspection translates the SIP text-based messages, recalculates the content length for the SDP portion of the message, and recalculates the packet length and checksum. It dynamically opens media connections for ports specified in the SDP portion of the SIP message as address/ports on which the endpoint should listen.

SIP inspection has a database with indices CALL_ID/FROM/TO from the SIP payload. These indices identify the call, the source, and the destination. This database contains the media addresses and media ports found in the SDP media information fields and the media type. There can be multiple media addresses and ports for a session. The adaptive security appliance opens RTP/RTCP connections between the two endpoints using these media addresses/ports.

The well-known port 5060 must be used on the initial call setup (INVITE) message; however, subsequent messages may not have this port number. The SIP inspection engine opens signaling connection pinholes, and marks these connections as SIP connections. This is done for the messages to reach the

SIP application and be translated.

As a call is set up, the SIP session is in the “transient” state until the media address and media port is received from the called endpoint in a Response message indicating the RTP port the called endpoint listens on. If there is a failure to receive the response messages within one minute, the signaling connection is torn down.

Once the final handshake is made, the call state is moved to active and the signaling connection remains until a BYE message is received.

If an inside endpoint initiates a call to an outside endpoint, a media hole is opened to the outside interface to allow RTP/RTCP UDP packets to flow to the inside endpoint media address and media port specified in the INVITE message from the inside endpoint. Unsolicited RTP/RTCP UDP packets to an inside interface does not traverse the adaptive security appliance, unless the adaptive security appliance configuration specifically allows it.

Select SIP Map

The Select SIP Map dialog box lets you select or create a new SIP map. A SIP map lets you change the configuration values used for SIP application inspection. The Select SIP Map table provides a list of previously configured maps that you can select for application inspection.

Fields

•

Use the default SIP inspection map—Specifies to use the default SIP map.

•

•

•

Select a SIP map for fine control over inspection

—



•

Enable encrypted traffic inspection check box—Select to enable the radio buttons to select a proxy type.

Proxy Type

–

TLS Proxy radio button—Use TLS Proxy to enable inspection of encrypted traffic.

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SIP Inspection


–

Phone Proxy radio button—Specifies to associate the Phone Proxy with the TLS Proxy that you select from the TLS Proxy Name field.

–

Configure button—Opens the Configure the Phone Proxy dialog box so that you can specify or edit Phone Proxy configuration settings.

UC-IME Proxy ratio button—Specifies to associate the UC-IME Proxy (Cisco Intercompany

Media Engine proxy) with the TLS Proxy that you select from the TLS Proxy Name field.

•

Configure button—Opens the Configure the UC-IME Proxy dialog box so that you can specify or edit UC-IME Proxy configuration settings.

TLS Proxy Name:—Name of existing TLS Proxy.

•

Manage—Opens the Add TLS Proxy dialog box to add a TLS Proxy.

Only one TLS proxy can be assigned to the Phone Proxy or UC-IME Proxy at a time. If you configure more than one service policy rule for Phone Proxy or UC-IME Proxy inspection and attempt to assign a different TLS proxy to them, ASDM displays a warning that all other service policy rules with Phone

Proxy or UC-IME inspection will be changed to use the latest selected TLS proxy.

The UC-IME Proxy configuration requires two TLS proxies – one for outbound traffic and one for inbound. Rather than associating the TLS proxies directly with the UC-IME Proxy, as is the case with phone proxy, the TLS proxies are associated with it indirectly via SIP inspection rules.

You associate a TLS proxy with the Phone Proxy while defining a SIP inspection action . ASDM will convert the association to the existing phone proxy.

Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

SIP Class Map

The SIP Class Map pane lets you configure SIP class maps for SIP inspection.



Fields

•

Name—Shows the SIP class map name.

•


–

–


Criterion—Shows the criterion of the SIP class map.

–

Value—Shows the value to match in the SIP class map.

38-26


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•

•

•

•


Add—Adds a SIP class map.

Edit—Edits a SIP class map.

Delete—Deletes a SIP class map.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit SIP Traffic Class Map

The Add/Edit SIP Traffic Class Map dialog box lets you define a SIP class map.

Fields

•

Name—Enter the name of the SIP class map, up to 40 characters in length.

•

Description—Enter the description of the SIP class map.

•

•

•

Add—Adds a SIP class map.

Edit—Edits a SIP class map.

Delete—Deletes a SIP class map.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

SIP Inspection

Add/Edit SIP Match Criterion

The Add/Edit SIP Match Criterion dialog box lets you define the match criterion and value for the SIP class map.

Fields

•




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38-27

SIP Inspection


•

•

•

•

•

•

Criterion—Specifies which criterion of SIP traffic to match.

–

–

Called Party—Match the called party as specified in the To header.

Calling Party—Match the calling party as specified in the From header.

–

–

Content Length—Match the Content Length header, between 0 and 65536.

Content Type—Match the Content Type header.

–

–

IM Subscriber—Match the SIP IM subscriber.

Message Path—Match the SIP Via header.

–

–

Request Method—Match the SIP request method.

Third-Party Registration—Match the requester of a third-party registration.

–

URI Length—Match a URI in the SIP headers, between 0 and 65536.

Called Party Criterion Values—Specifies to match the called party. Applies the regular expression match.

–

–



–

–



Calling Party Criterion Values—Specifies to match the calling party. Applies the regular expression match.

–


–

–



–


Content Length Criterion Values—Specifies to match a SIP content header of a length greater than specified.

–


Content Type Criterion Values—Specifies to match a SIP content header type.

–

–

SDP—Match an SDP SIP content header type.

Regular Expression—Match a regular expression.





IM Subscriber Criterion Values—Specifies to match the IM subscriber. Applies the regular expression match.

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SIP Inspection

•

•

•

•

–

–

–




–


Message Path Criterion Values—Specifies to match a SIP Via header. Applies the regular expression match.

–

–



–

–



Request Method Criterion Values—Specifies to match a SIP request method.

–

Request Method—Specifies a request method: ack, bye, cancel, info, invite, message, notify, options, prack, refer, register, subscribe, unknown, update.

Third-Party Registration Criterion Values—Specifies to match the requester of a third-party registration. Applies the regular expression match.

–


–

–



–


URI Length Criterion Values—Specifies to match a URI of a selected type and greater than the specified length in the SIP headers.

–

–

URI type—Specifies to match either SIP URI or TEL URI.

Greater Than Length—Length in bytes.

Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

SIP Inspect Map

The SIP pane lets you view previously configured SIP application inspection maps. A SIP map lets you change the default configuration values used for SIP application inspection.

OL-20339-01


38-29

SIP Inspection


SIP is a widely used protocol for Internet conferencing, telephony, presence, events notification, and instant messaging. Partially because of its text-based nature and partially because of its flexibility, SIP networks are subject to a large number of security threats.

SIP application inspection provides address translation in message header and body, dynamic opening of ports and basic sanity checks. It also supports application security and protocol conformance, which enforce the sanity of the SIP messages, as well as detect SIP-based attacks.

Fields

•

SIP Inspect Maps—Table that lists the defined SIP inspect maps.

•

Add—Configures a new SIP inspect map. To edit a SIP inspect map, choose the SIP entry in the SIP

Inspect Maps table and click

Customize

.

•

•

Delete—Deletes the inspect map selected in the SIP Inspect Maps table.


–

Low—Default.

SIP instant messaging (IM) extensions: Enabled.

Non-SIP traffic on SIP port: Permitted.

Hide server’s and endpoint’s IP addresses: Disabled.

Mask software version and non-SIP URIs: Disabled.

Ensure that the number of hops to destination is greater than 0: Enabled.

–

RTP conformance: Not enforced.

SIP conformance: Do not perform state checking and header validation.

Medium






–

RTP conformance: Enforced.

Limit payload to audio or video, based on the signaling exchange: No

SIP conformance: Drop packets that fail state checking.

High


Non-SIP traffic on SIP port: Denied.


Mask software version and non-SIP URIs: Enabled.



Limit payload to audio or video, based on the signaling exchange: Yes

SIP conformance: Drop packets that fail state checking and packets that fail header validation.

–

Customize—Opens the Add/Edit SIP Policy Map dialog box for additional settings.

38-30


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–


Modes


SIP Inspection

Firewall Mode

Routed



Multiple

Context

• • • •

System

—

Add/Edit SIP Policy Map (Security Level)

The Add/Edit SIP Policy Map pane lets you configure the security level and additional settings for SIP application inspection maps.

Fields

•

Name—When adding a SIP, enter the name of the SIP map. When editing a SIP map, the name of the previously configured SIP map is shown.

•

•

Description—Enter the description of the SIP map, up to 200 characters in length.


–

Low—Default.




–




SIP conformance: Do not perform state checking and header validation.

Medium




–




Limit payload to audio or video, based on the signaling exchange: No

SIP conformance: Drop packets that fail state checking.

High


Non-SIP traffic on SIP port: Denied.

OL-20339-01


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SIP Inspection


•


Mask software version and non-SIP URIs: Enabled.


–


Limit payload to audio or video, based on the signaling exchange: Yes

SIP conformance: Drop packets that fail state checking and packets that fail header validation.


Details—Shows additional filtering, IP address privacy, hop count, RTP conformance, SIP conformance, field masking, and inspections settings to configure.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit SIP Policy Map (Details)

The Add/Edit SIP Policy Map pane lets you configure the security level and additional settings for SIP application inspection maps.

Fields

•

Name—When adding a SIP, enter the name of the SIP map. When editing a SIP map, the name of the previously configured SIP map is shown.

•

Description—Enter the description of the SIP map, up to 200 characters in length.

•

•

Security Level—Shows the security level settings to configure

Filtering—Tab that lets you configure the filtering settings for SIP.

–

–

Enable SIP instant messaging (IM) extensions—Enables Instant Messaging extensions. Default is enabled.

Permit non-SIP traffic on SIP port—Permits non-SIP traffic on SIP port. Permitted by default.

•

•

•

IP Address Privacy—Tab that lets you configure the IP address privacy settings for SIP.

–

Hide server’s and endpoint’s IP addresses—Enables IP address privacy. Disabled by default.

Hop Count—Tab that lets you configure the hop count settings for SIP.

–

Ensure that number of hops to destination is greater than 0—Enables check for the value of

Max-Forwards header is zero.

Action—Drop packet, Drop Connection, Reset, Log.

Log—Enable or Disable.

RTP Conformance—Tab that lets you configure the RTP conformance settings for SIP.

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SIP Inspection

•

•

•

–

Limit payload to audio or video, based on the signaling exchange—Enforces payload type to be audio/video based on the signaling exchange.

SIP Conformance—Tab that lets you configure the SIP conformance settings for SIP.

–

Check RTP packets for protocol conformance—Checks RTP/RTCP packets flowing on the pinholes for protocol conformance.

–

Enable state transition checking—Enables SIP state checking.



Enable strict validation of header fields—Enables validation of SIP header fields.



Field Masking—Tab that lets you configure the field masking settings for SIP.

–

Inspect non-SIP URIs—Enables non-SIP URI inspection in Alert-Info and Call-Info headers.

–

–

–

–

Action—Mask or Log.


Inspect server’s and endpoint’s software version—Inspects SIP endpoint software version in

User-Agent and Server headers.

Action—Mask or Log.


Inspections—Tab that shows you the SIP inspection configuration and lets you add or edit.

–

–


Criterion—Shows the criterion of the SIP inspection.

–

–

–

–

Value—Shows the value to match in the SIP inspection.



Add—Opens the Add SIP Inspect dialog box to add a SIP inspection.

–

Edit—Opens the Edit SIP Inspect dialog box to edit a SIP inspection.

Delete—Deletes a SIP inspection.



Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

OL-20339-01


38-33


SIP Inspection

Add/Edit SIP Inspect

The Add/Edit SIP Inspect dialog box lets you define the match criterion and value for the SIP inspect map.

Fields

•

Single Match—Specifies that the SIP inspect has only one match statement.

•


•



Criterion—Specifies which criterion of SIP traffic to match.

–

–

Called Party—Match a called party as specified in the To header.

Calling Party—Match a calling party as specified in the From header.

–

–

Content Length—Match a content length header.

Content Type—Match a content type header.

•

•

•

•

–

–

IM Subscriber—Match a SIP IM subscriber.

Message Path—Match a SIP Via header.

–

–

Request Method—Match a SIP request method.

Third-Party Registration—Match the requester of a third-party registration.

–

URI Length—Match a URI in the SIP headers.

Called Party Criterion Values—Specifies to match the called party. Applies the regular expression match.

–

–



–

–



Calling Party Criterion Values—Specifies to match the calling party. Applies the regular expression match.

–


–

–



–


Content Length Criterion Values—Specifies to match a SIP content header of a length greater than specified.

–


Content Type Criterion Values—Specifies to match a SIP content header type.

–

SDP—Match an SDP SIP content header type.

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SIP Inspection

•

•

•

•

•

•

–

Regular Expression—Match a regular expression.



IM Subscriber Criterion Values—Specifies to match the IM subscriber. Applies the regular expression match.

–


–



–



–


Message Path Criterion Values—Specifies to match a SIP Via header. Applies the regular expression match.

–

–



–

–



Request Method Criterion Values—Specifies to match a SIP request method.

–

Request Method—Specifies a request method: ack, bye, cancel, info, invite, message, notify, options, prack, refer, register, subscribe, unknown, update.

Third-Party Registration Criterion Values—Specifies to match the requester of a third-party registration. Applies the regular expression match.

–


–

–



–


URI Length Criterion Values—Specifies to match a URI in the SIP headers greater than specified length.

–

–

URI type—Specifies to match either SIP URI or TEL URI.

Greater Than Length—Length in bytes.

Multiple Matches—Specifies multiple matches for the SIP inspection.

–

SIP Traffic Class—Specifies the SIP traffic class match.

–

Manage—Opens the Manage SIP Class Maps dialog box to add, edit, or delete SIP Class Maps.

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38-35


Skinny (SCCP) Inspection

•

Actions—Primary action and log settings.

–

–

Action—Drop packet, drop connection, reset, log. Note: Limit rate (pps) action is available for request methods invite and register.


Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—


•

•

•

•

•

•

This section describes SCCP application inspection. This section includes the following topics:

SCCP Inspection Overview, page 38-36

Supporting Cisco IP Phones, page 38-37

•

•

•

Restrictions and Limitations, page 38-37

Select SCCP (Skinny) Map, page 38-38

SCCP (Skinny) Inspect Map, page 38-38

Message ID Filtering, page 38-40

Add/Edit SCCP (Skinny) Policy Map (Security Level), page 38-40

Add/Edit SCCP (Skinny) Policy Map (Details), page 38-41

Add/Edit Message ID Filter, page 38-42

SCCP Inspection Overview

Note

For specific information about setting up the Phone Proxy on the adaptive security appliance, which is part of the Cisco Unified Communications architecture and supports IP phone deployment, see

Chapter 43, “Configuring the Cisco Phone Proxy.”

.

Skinny (SCCP) is a simplified protocol used in VoIP networks. Cisco IP Phones using SCCP can coexist in an H.323 environment. When used with Cisco CallManager, the SCCP client can interoperate with

H.323 compliant terminals.

The adaptive security appliance supports PAT and NAT for SCCP. PAT is necessary if you have more IP phones than global IP addresses for the IP phones to use. By supporting NAT and PAT of SCCP Signaling packets, Skinny application inspection ensures that all SCCP signalling and media packets can traverse the adaptive security appliance.

38-36


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Normal traffic between Cisco CallManager and Cisco IP Phones uses SCCP and is handled by SCCP inspection without any special configuration. The adaptive security appliance also supports DHCP options 150 and 66, which it accomplishes by sending the location of a TFTP server to Cisco IP Phones and other DHCP clients. Cisco IP Phones might also include DHCP option 3 in their requests, which sets the default route.

Note

The adaptive security appliance supports inspection of traffic from Cisco IP Phones running SCCP protocol version 19 and earlier.

Supporting Cisco IP Phones

Note

For specific information about setting up the Phone Proxy on the adaptive security appliance, which is part of the Cisco Unified Communications architecture and supports IP phone deployment, see

Chapter 43, “Configuring the Cisco Phone Proxy.” .

In topologies where Cisco CallManager is located on the higher security interface with respect to the

Cisco IP Phones, if NAT is required for the Cisco CallManager IP address, the mapping must be

static

as a Cisco IP Phone requires the Cisco CallManager IP address to be specified explicitly in its configuration. An static identity entry allows the Cisco CallManager on the higher security interface to accept registrations from the Cisco IP Phones.

Cisco IP Phones require access to a TFTP server to download the configuration information they need to connect to the Cisco CallManager server.

When the Cisco IP Phones are on a lower security interface compared to the TFTP server, you must use an access list to connect to the protected TFTP server on UDP port 69. While you do need a static entry for the TFTP server, this does not have to be an identity static entry. When using NAT, an identity static entry maps to the same IP address. When using PAT, it maps to the same IP address and port.

When the Cisco IP Phones are on a

higher

security interface compared to the TFTP server and

Cisco CallManager, no access list or static entry is required to allow the Cisco IP Phones to initiate the connection.

Restrictions and Limitations

The following are limitations that apply to the current version of PAT and NAT support for SCCP:

•

PAT does not work with configurations containing the

alias

command.

•

Outside NAT or PAT is

not

supported.

If the address of an internal Cisco CallManager is configured for NAT or PAT to a different IP address or port, registrations for external Cisco IP Phones fail because the adaptive security appliance currently does not support NAT or PAT for the file content transferred over TFTP. Although the adaptive security appliance supports NAT of TFTP messages and opens a pinhole for the TFTP file, the adaptive security appliance cannot translate the Cisco CallManager IP address and port embedded in the Cisco IP Phone configuration files that are transferred by TFTP during phone registration.

Note

The adaptive security appliance supports stateful failover of SCCP calls except for calls that are in the middle of call setup.

OL-20339-01


38-37



Select SCCP (Skinny) Map

The Select SCCP (Skinny) Map dialog box lets you select or create a new SCCP (Skinny) map. An SCCP

(Skinny) map lets you change the configuration values used for SCCP (Skinny) application inspection.

The Select SCCP (Skinny) Map table provides a list of previously configured maps that you can select for application inspection.

Fields

•

Use the default SCCP (Skinny) inspection map—Specifies to use the default SCCP (Skinny) map.

•

Select an SCCP (Skinny) map for fine control over inspection

—


•

•


Encrypted Traffic Inspection—Lets you specify TLS proxy settings for the inspect map.

–

–

Do not inspect Encrypted Traffic—Disables the inspection of Skinny application inspection.

Use Phone Proxy to enable inspection of encrypted traffic—Uses the Phone Proxy configured on the adaptive security appliance to inspect Skinny application traffic. See

Chapter 43,

“Configuring the Cisco Phone Proxy.”

–

Use TLS Proxy to enable inspection of encrypted traffic—Specifies to use Transaction Layer

Security Proxy to enable inspection of encryped traffic.

TLS Proxy Name:—Name of existing TLS Proxy.

New—Opens the Add TLS Proxy dialog box to add a TLS Proxy.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

SCCP (Skinny) Inspect Map

The SCCP (Skinny) pane lets you view previously configured SCCP (Skinny) application inspection maps. An SCCP (Skinny) map lets you change the default configuration values used for SCCP (Skinny) application inspection.

Skinny application inspection performs translation of embedded IP address and port numbers within the packet data, and dynamic opening of pinholes. It also performs additional protocol conformance checks and basic state tracking.

Fields

•

SCCP (Skinny) Inspect Maps—Table that lists the defined SCCP (Skinny) inspect maps.

•

•

Add—Configures a new SCCP (Skinny) inspect map. To edit an SCCP (Skinny) inspect map, choose the SCCP (Skinny) entry in the SCCP (Skinny) Inspect Maps table and click

Customize

.

Delete—Deletes the inspect map selected in the SCCP (Skinny) Inspect Maps table.

38-38


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•


–

Low—Default.

Registration: Not enforced.

Maximum message ID: 0x181.

Minimum prefix length: 4

Media timeout: 00:05:00

Signaling timeout: 01:00:00.

–


Medium



Minimum prefix length: 4.

Media timeout: 00:01:00.



–

–

–

–

Limit payload to audio or video, based on the signaling exchange: No.

High

Registration: Enforced.



Maximum prefix length: 65536.




Limit payload to audio or video, based on the signaling exchange: Yes.

Message ID Filtering—Opens the Messaging ID Filtering dialog box for configuring message

ID filters.

Customize—Opens the Add/Edit SCCP (Skinny) Policy Map dialog box for additional settings.


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

OL-20339-01


38-39



Message ID Filtering

The Message ID Filtering dialog box lets you configure the settings for a message ID filter.

•

•

•

Fields

•


•


•

•

•

•




Add—Opens the Add Message ID Filtering dialog box to add a message ID filter.

•

Edit—Opens the Edit Message ID Filtering dialog box to edit a message ID filter.

Delete—Deletes a message ID filter.



Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit SCCP (Skinny) Policy Map (Security Level)

The Add/Edit SCCP (Skinny) Policy Map pane lets you configure the security level and additional settings for SCCP (Skinny) application inspection maps.

Fields

•

Name—When adding an SCCP (Skinny) map, enter the name of the SCCP (Skinny) map. When editing an SCCP (Skinny) map, the name of the previously configured SCCP (Skinny) map is shown.

•

•

Description—Enter the description of the SCCP (Skinny) map, up to 200 characters in length.


–

Low—Default.



Minimum prefix length: 4

Media timeout: 00:05:00



38-40


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•

–

–

Medium







Limit payload to audio or video, based on the signaling exchange: No.

High

Registration: Enforced.



Maximum prefix length: 65536.



–

–


Limit payload to audio or video, based on the signaling exchange: Yes.

Message ID Filtering—Opens the Messaging ID Filtering dialog box for configuring message

ID filters.


Details—Shows additional parameter, RTP conformance, and message ID filtering settings to configure.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit SCCP (Skinny) Policy Map (Details)

The Add/Edit SCCP (Skinny) Policy Map pane lets you configure the security level and additional settings for SCCP (Skinny) application inspection maps.

Fields

•

Name—When adding an SCCP (Skinny) map, enter the name of the SCCP (Skinny) map. When editing an SCCP (Skinny) map, the name of the previously configured SCCP (Skinny) map is shown.

•


OL-20339-01


38-41



•

•

•

•

Security Level—Shows the security level and message ID filtering settings to configure.

Parameters—Tab that lets you configure the parameter settings for SCCP (Skinny).

–

Enforce endpoint registration—Enforce that Skinny endpoints are registered before placing or receiving calls.

–

Maximum Message ID—Specify value of maximum SCCP message ID allowed.

SCCP Prefix Length—Specifies prefix length value in Skinny messages.

–

–

Minimum Prefix Length—Specify minimum value of SCCP prefix length allowed.

Maximum Prefix Length—Specify maximum value of SCCP prefix length allowed.

Media Timeout—Specify timeout value for media connections.

Signaling Timeout—Specify timeout value for signaling connections.

RTP Conformance—Tab that lets you configure the RTP conformance settings for SCCP (Skinny).

–

Check RTP packets for protocol conformance—Checks RTP/RTCP packets flowing on the pinholes for protocol conformance.

Limit payload to audio or video, based on the signaling exchange—Enforces the payload type to be audio/video based on the signaling exchange.

Message ID Filtering—Tab that lets you configure the message ID filtering settings for SCCP

(Skinny).

–

–



–

–



–

–


Add—Opens the Add Message ID Filtering dialog box to add a message ID filter.

–

–

Edit—Opens the Edit Message ID Filtering dialog box to edit a message ID filter.

Delete—Deletes a message ID filter.

–

–



Modes


Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

Add/Edit Message ID Filter

The Add Message ID Filter dialog box lets you configure message ID filters.

38-42


OL-20339-01



Fields

•




•

Criterion—Specifies which criterion of SCCP (Skinny) traffic to match.

–

Message ID—Match specified message ID.

–

Message ID—Specify value of maximum SCCP message ID allowed.

Message ID Range—Match specified message ID range.

•

•

Lower Message ID—Specify lower value of SCCP message ID allowed.

Upper Message ID—Specify upper value of SCCP message ID allowed.

Action—Drop packet.


OL-20339-01


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38-44


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C H A P T E R

39

Configuring Inspection of Database and

Directory Protocols



•

ILS Inspection, page 39-1

•

•

SQL*Net Inspection, page 39-2

Sun RPC Inspection, page 39-3

ILS Inspection

The ILS inspection engine provides NAT support for Microsoft NetMeeting, SiteServer, and Active

Directory products that use LDAP to exchange directory information with an ILS server.

The adaptive security appliance supports NAT for ILS, which is used to register and locate endpoints in the ILS or SiteServer Directory. PAT cannot be supported because only IP addresses are stored by an

LDAP database.

For search responses, when the LDAP server is located outside, NAT should be considered to allow internal peers to communicate locally while registered to external LDAP servers. For such search responses, xlates are searched first, and then DNAT entries to obtain the correct address. If both of these searches fail, then the address is not changed. For sites using NAT 0 (no NAT) and not expecting DNAT interaction, we recommend that the inspection engine be turned off to provide better performance.

Additional configuration may be necessary when the ILS server is located inside the adaptive security appliance border. This would require a hole for outside clients to access the LDAP server on the specified port, typically TCP 389.

Because ILS traffic only occurs on the secondary UDP channel, the TCP connection is disconnected after the TCP inactivity interval. By default, this interval is 60 minutes and can be adjusted using the

timeout

command.

ILS/LDAP follows a client/server model with sessions handled over a single TCP connection.

Depending on the client's actions, several of these sessions may be created.

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39-1

SQL*Net Inspection

Chapter 39 Configuring Inspection of Database and Directory Protocols

During connection negotiation time, a BIND PDU is sent from the client to the server. Once a successful

BIND RESPONSE from the server is received, other operational messages may be exchanged (such as

ADD, DEL, SEARCH, or MODIFY) to perform operations on the ILS Directory. The ADD REQUEST and SEARCH RESPONSE PDUs may contain IP addresses of NetMeeting peers, used by H.323 (SETUP and CONNECT messages) to establish the NetMeeting sessions. Microsoft NetMeeting v2.X and v3.X provides ILS support.

The ILS inspection performs the following operations:

•

Decodes the LDAP REQUEST/RESPONSE PDUs using the BER decode functions

•

•

•

•

•

•

Parses the LDAP packet

Extracts IP addresses

Translates IP addresses as necessary

Encodes the PDU with translated addresses using BER encode functions

Copies the newly encoded PDU back to the TCP packet

Performs incremental TCP checksum and sequence number adjustment

ILS inspection has the following limitations:

•

Referral requests and responses are not supported

•

•

Users in multiple directories are not unified

Single users having multiple identities in multiple directories cannot be recognized by NAT

Note

Because H.225 call signalling traffic only occurs on the secondary UDP channel, the TCP connection is disconnected after the interval specified by the TCP option in the Configuration > Firewall > Advanced

> Global Timeouts pane. By default, this interval is set at 60 minutes.

SQL*Net Inspection

SQL*Net inspection is enabled by default.

The SQL*Net protocol consists of different packet types that the adaptive security appliance handles to make the data stream appear consistent to the Oracle applications on either side of the adaptive security appliance.

The default port assignment for SQL*Net is 1521. This is the value used by Oracle for SQL*Net, but this value does not agree with IANA port assignments for Structured Query Language (SQL).

Note

Disable SQL*Net inspection when SQL data transfer occurs on the same port as the SQL control TCP port 1521. The security appliance acts as a proxy when SQL*Net inspection is enabled and reduces the client window size from 65000 to about 16000 causing data transfer issues.

The adaptive security appliance translates all addresses and looks in the packets for all embedded ports to open for SQL*Net Version 1.

For SQL*Net Version 2, all DATA or REDIRECT packets that immediately follow REDIRECT packets with a zero data length will be fixed up.

The packets that need fix-up contain embedded host/port addresses in the following format:

(ADDRESS=(PROTOCOL=tcp)(DEV=6)(

HOST=a.b.c.

d)(

PORT=

a))

39-2


OL-20339-01


Sun RPC Inspection

SQL*Net Version 2 TNSFrame types (Connect, Accept, Refuse, Resend, and Marker) will not be scanned for addresses to NAT nor will inspection open dynamic connections for any embedded ports in the packet.

SQL*Net Version 2 TNSFrames, Redirect, and Data packets will be scanned for ports to open and addresses to NAT, if preceded by a REDIRECT TNSFrame type with a zero data length for the payload.

When the Redirect message with data length zero passes through the adaptive security appliance, a flag will be set in the connection data

s tructure to expect the Data or Redirect message that follows to be translated and ports to be dynamically opened. If one of the TNS frames in the preceding paragraph arrive after the Redirect message, the flag will be reset.

The SQL*Net inspection engine will recalculate the checksum, change IP, TCP lengths, and readjust

Sequence Numbers and Acknowledgment Numbers using the delta of the length of the new and old message.

SQL*Net Version 1 is assumed for all other cases. TNSFrame types (Connect, Accept, Refuse, Resend,

Marker, Redirect, and Data) and all packets will be scanned for ports and addresses. Addresses will be translated and port connections will be opened.


This section describes Sun RPC application inspection. This section includes the following topics:

•

Sun RPC Inspection Overview, page 39-3

•

•

“SUNRPC Server” section on page 39-3

“Add/Edit SUNRPC Service” section on page 39-4

Sun RPC Inspection Overview

The Sun RPC inspection engine enables or disables application inspection for the Sun RPC protocol. Sun

RPC is used by NFS and NIS. Sun RPC services can run on any port. When a client attempts to access an Sun RPC service on a server, it must learn the port that service is running on. It does this by querying the port mapper process, usually rpcbind, on the well-known port of 111.

The client sends the Sun RPC program number of the service and the port mapper process responds with the port number of the service. The client sends its Sun RPC queries to the server, specifying the port identified by the port mapper process. When the server replies, the adaptive security appliance intercepts this packet and opens both embryonic TCP and UDP connections on that port.

Note

NAT or PAT of Sun RPC payload information is not supported.

SUNRPC Server

The Configuration > Firewall > Advanced > SUNRPC Server pane shows which SunRPC services can traverse the adaptive security appliance and their specific timeout, on a per server basis.

Fields

•

Interface—Displays the interface on which the SunRPC server resides.

OL-20339-01


39-3



•

•

•

•

•

•

IP address

—

Displays the IP address of the SunRPC server.

Mask—Displays the subnet mask of the IP Address of the SunRPC server.

Service ID

—

Displays the SunRPC program number, or service ID, allowed to traverse the adaptive security appliance.

Protocol—Displays the SunRPC transport protocol (TCP or UDP).

Port—Displays the SunRPC protocol port range.

Timeout—Displays the idle time after which the access for the SunRPC service traffic is closed.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit SUNRPC Service

The Configuration > Firewall > Advanced > SUNRPC Server > Add/Edit SUNRPC Service dialog box lets you specify what SunRPC services are allowed to traverse the adaptive security appliance and their specific timeout, on a per-server basis.

Fields

•

Interface Name

—

Specifies the interface on which the SunRPC server resides.

•

Protocol—Specifies the SunRPC transport protocol (TCP or UDP).

•

•

•

•

•

IP address

—

Specifies the IP address of the SunRPC server.

Port—Specifies the SunRPC protocol port range.

Mask—Specifies the subnet mask of the IP Address of the SunRPC server.

Timeout—Specifies the idle time after which the access for the SunRPC service traffic is closed.

Format is HH:MM:SS.

Service ID—Specifies the SunRPC program number, or service ID, allowed to traverse the adaptive security appliance.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

39-4


OL-20339-01

C H A P T E R

40

Configuring Inspection for Management

Application Protocols



•

DCERPC Inspection, page 40-1

•

•

•

•

•

GTP Inspection, page 40-5

RADIUS Accounting Inspection, page 40-12

RSH Inspection, page 40-16

SNMP Inspection, page 40-16

XDMCP Inspection, page 40-18

DCERPC Inspection

This section describes the DCERPC inspection engine. This section includes the following topics:

•

DCERPC Overview, page 40-1

•

•

•

“Select DCERPC Map” section on page 40-2

“DCERPC Inspect Map” section on page 40-2

“Add/Edit DCERPC Policy Map” section on page 40-4

DCERPC Overview

DCERPC is a protocol widely used by Microsoft distributed client and server applications that allows software clients to execute programs on a server remotely.


40-1 OL-20339-01


Chapter 40 Configuring Inspection for Management Application Protocols

This typically involves a client querying a server called the Endpoint Mapper listening on a well known port number for the dynamically allocated network information of a required service. The client then sets up a secondary connection to the server instance providing the service. The security appliance allows the appropriate port number and network address and also applies NAT, if needed, for the secondary connection.

DCERPC inspect maps inspect for native TCP communication between the EPM and client on well known TCP port 135. Map and lookup operations of the EPM are supported for clients. Client and server can be located in any security zone. The embedded server IP address and Port number are received from the applicable EPM response messages. Since a client may attempt multiple connections to the server port returned by EPM, multiple use of pinholes are allowed, which have user configurable timeouts.

Note

DCERPC inspection only supports communication between the EPM and clients to open pinholes through theadaptive security appliance. Clients using RPC communication that does not use the EPM is not supported with DCERPC inspection.

Select DCERPC Map

The Select DCERPC Map dialog box lets you select or create a new DCERPC map. A DCERPC map lets you change the configuration values used for DCERPC application inspection. The Select DCERPC

Map table provides a list of previously configured maps that you can select for application inspection.

Fields

•

Use the default DCERPC inspection map—Specifies to use the default DCERPC map.

•

•

Select a DCERPC map for fine control over inspection

—



Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

DCERPC Inspect Map

The DCERPC pane lets you view previously configured DCERPC application inspection maps. A

DCERPC map lets you change the default configuration values used for DCERPC application inspection.

DCERPC is a protocol widely used by Microsoft distributed client and server applications that allows software clients to execute programs on a server remotely.

40-2


OL-20339-01



This typically involves a client querying a server called the Endpoint Mapper (EPM) listening on a well known port number for the dynamically allocated network information of a required service. The client then sets up a secondary connection to the server instance providing the service. The security appliance allows the appropriate port number and network address and also applies NAT, if needed, for the secondary connection.

DCERPC inspect maps inspect for native TCP communication between the EPM and client on well known TCP port 135. Map and lookup operations of the EPM are supported for clients. Client and server can be located in any security zone. The embedded server IP address and Port number are received from the applicable EPM response messages. Because a client may attempt multiple connections to the server port returned by EPM, multiple use of pinholes are allowed, which have user configurable timeouts.

Fields

•

DCERPC Inspect Maps—Table that lists the defined DCERPC inspect maps.

•

Add—Configures a new DCERPC inspect map. To edit a DCERPC inspect map, choose the

DCERPC entry in the DCERPC Inspect Maps table and click

Customize

.

•

•

Delete—Deletes the inspect map selected in the DCERPC Inspect Maps table.


–

Low

Pinhole timeout: 00:02:00

–

–

–

–

Endpoint mapper service: not enforced

Endpoint mapper service lookup: enabled

Endpoint mapper service lookup timeout: 00:05:00

Medium—Default.



Endpoint mapper service lookup: disabled.

High


Endpoint mapper service: enforced

Endpoint mapper service lookup: disabled

Customize—Opens the Add/Edit DCERPC Policy Map dialog box for additional settings.


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

OL-20339-01


40-3



Add/Edit DCERPC Policy Map

The Add/Edit DCERPC Policy Map pane lets you configure the security level and parameters for

DCERPC application inspection maps.

Fields

•

Name—When adding a DCERPC map, enter the name of the DCERPC map. When editing a

DCERPC map, the name of the previously configured DCERPC map is shown.

•

Description—Enter the description of the DCERPC map, up to 200 characters in length.

•


–

Low



–

Endpoint mapper service lookup: enabled

Endpoint mapper service lookup timeout: 00:05:00

Medium—Default.


–


Endpoint mapper service lookup: disabled.

High


•

Endpoint mapper service: enforced

Endpoint mapper service lookup: disabled

–


Details—Shows the Parameters to configure additional settings.

–

–

Pinhole Timeout—Sets the pinhole timeout. Because a client may use the server information returned by the endpoint mapper for multiple connections, the timeout value is configurable based on the client application environment. Range is from 0:0:1 to 1193:0:0. Default is 2 minutes.

Enforce endpoint-mapper service—Enforces endpoint mapper service during binding.

–

Enable endpoint-mapper service lookup—Enables the lookup operation of the endpoint mapper service. If disabled, the pinhole timeout is used.

Enforce Service Lookup Timeout—Enforces the service lookup timeout specified.

Service Lookup Timeout—Sets the timeout for pinholes from lookup operation.

Modes


40-4


OL-20339-01


GTP Inspection

Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

GTP Inspection

This section describes the GTP inspection engine. This section includes the following topics:

•

GTP Inspection Overview, page 40-5

•

•

•

•

•

•

“Select GTP Map” section on page 40-6

“GTP Inspect Map” section on page 40-7

“IMSI Prefix Filtering” section on page 40-8

“Add/Edit GTP Policy Map (Security Level)” section on page 40-8

“Add/Edit GTP Policy Map (Details)” section on page 40-9

“Add/Edit GTP Map” section on page 40-11

Note

GTP inspection requires a special license.

GTP Inspection Overview

GPRS provides uninterrupted connectivity for mobile subscribers between GSM networks and corporate networks or the Internet. The GGSN is the interface between the GPRS wireless data network and other networks. The SGSN performs mobility, data session management, and data compression (See

Figure 40-1 ).

OL-20339-01


40-5

GTP Inspection

Figure 40-1 GPRS Tunneling Protocol


Internet

MS

Home PLMN

Gn

SGSN GGSN Gi

Gp

Corporate network 2

Corporate network 1

GRX

Roaming partner

(visited PLMN)

The UMTS is the commercial convergence of fixed-line telephony, mobile, Internet and computer technology. UTRAN is the networking protocol used for implementing wireless networks in this system.

GTP allows multi-protocol packets to be tunneled through a UMTS/GPRS backbone between a GGSN, an SGSN and the UTRAN.

GTP does not include any inherent security or encryption of user data, but using GTP with the adaptive security appliance helps protect your network against these risks.

The SGSN is logically connected to a GGSN using GTP. GTP allows multiprotocol packets to be tunneled through the GPRS backbone between GSNs. GTP provides a tunnel control and management protocol that allows the SGSN to provide GPRS network access for a mobile station by creating, modifying, and deleting tunnels. GTP uses a tunneling mechanism to provide a service for carrying user data packets.

Note

When using GTP with failover, if a GTP connection is established and the active unit fails before data is transmitted over the tunnel, the GTP data connection (with a “j” flag set) is not replicated to the standby unit. This occurs because the active unit does not replicate embryonic connections to the standby unit.

Select GTP Map

The Select GTP Map dialog box lets you select or create a new GTP map. A GTP map lets you change the configuration values used for GTP application inspection. The Select GTP Map table provides a list of previously configured maps that you can select for application inspection.

Note

GTP inspection requires a special license. If you try to enable GTP application inspection on a adaptive security appliance without the required license, the adaptive security appliance displays an error message.

40-6


OL-20339-01


GTP Inspection

Fields

•

Use the default GTP inspection map—Specifies to use the default GTP map.

•

Select an GTP map for fine control over inspection

—


•


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

GTP Inspect Map

The GTP pane lets you view previously configured GTP application inspection maps. A GTP map lets you change the default configuration values used for GTP application inspection.

GTP is a relatively new protocol designed to provide security for wireless connections to TCP/IP networks, such as the Internet. You can use a GTP map to control timeout values, message sizes, tunnel counts, and GTP versions traversing the security appliance.

Note

GTP inspection is not available without a special license.

Fields

•

GTP Inspect Maps—Table that lists the defined GTP inspect maps.

•

•

•

Add—Configures a new GTP inspect map. To edit a GTP inspect map, choose the GTP entry in the

GTP Inspect Maps table and click

Customize

.

Delete—Deletes the inspect map selected in the GTP Inspect Maps table.

Security Level—Security level low only.

–

Do not Permit Errors

–

–

–

–

Maximum Number of Tunnels: 500

GSN timeout: 00:30:00

Pdp-Context timeout: 00:30:00

Request timeout: 00:01:00

•

•

–

–

–

–


Tunnel timeout: 01:00:00.

T3-response timeout: 00:00:20.

Drop and log unknown message IDs.

IMSI Prefix Filtering—Opens the IMSI Prefix Filtering dialog box to configure IMSI prefix filters.

Customize—Opens the Add/Edit GTP Policy Map dialog box for additional settings.


OL-20339-01 40-7

GTP Inspection


•


Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

IMSI Prefix Filtering

The IMSI Prefix tab lets you define the IMSI prefix to allow within GTP requests.

Fields

•

Mobile Country Code—Defines the non-zero, three-digit value identifying the mobile country code.

One or two-digit entries will be prepended by 0 to create a three-digit value.

•

•

•

Mobile Network Code—Defines the two or three-digit value identifying the network code.

Add—Add the specified country code and network code to the IMSI Prefix table.

Delete—Deletes the specified country code and network code from the IMSI Prefix table.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit GTP Policy Map (Security Level)

The Add/Edit GTP Policy Map pane lets you configure the security level and additional settings for GTP application inspection maps.

Fields

•

Name—When adding a GTP map, enter the name of the GTP map. When editing a GTP map, the name of the previously configured GTP map is shown.

•

Description—Enter the description of the GTP map, up to 200 characters in length.

•

Security Level—Security level low only.

Do not Permit Errors

Maximum Number of Tunnels: 500

GSN timeout: 00:30:00

40-8


OL-20339-01


GTP Inspection

•

–

Pdp-Context timeout: 00:30:00

Request timeout: 00:01:00


Tunnel timeout: 01:00:00.

T3-response timeout: 00:00:20.

Drop and log unknown message IDs.

IMSI Prefix Filtering—Opens the IMSI Prefix Filtering dialog box to configure IMSI prefix filters.

–


Details—Shows the Parameters, IMSI Prefix Filtering, and Inspections tabs to configure additional settings.

Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

Add/Edit GTP Policy Map (Details)

The Add/Edit GTP Policy Map pane lets you configure the security level and additional settings for GTP application inspection maps.

Fields

•

Name—When adding a GTP map, enter the name of the GTP map. When editing a GTP map, the name of the previously configured GTP map is shown.

•

•

•

Description—Enter the description of the GTP map, up to 200 characters in length.

Security Level—Shows the security level and IMSI prefix filtering settings to configure.

Permit Parameters—Tab that lets you configure the permit parameters for the GTP inspect map.

–

Object Groups to Add

•

–

–

From object group—Specify an object group or use the browse button to open the Add Network

Object Group dialog box.

To object group—Specify an object group or use the browse button to open the Add Network

Object Group dialog box.



–

Permit Errors—Lets any packets that are invalid or that encountered an error during inspection to be sent through the adaptive security appliance instead of being dropped. By default, all invalid packets or packets that failed during parsing are dropped.

General Parameters—Tab that lets you configure the general parameters for the GTP inspect map.


OL-20339-01 40-9

GTP Inspection


•

•

–

Maximum Number of Requests—Lets you change the default for the maximum request queue size allowed. The default for the maximum request queue size is 200. Specifies the maximum number of GTP requests that will be queued waiting for a response. The permitted range is from

1 to 9999999.

–

–

Maximum Number of Tunnels—Lets you change the default for the maximum number of tunnels allowed. The default tunnel limit is 500. Specifies the maximum number of tunnels allowed. The permitted range is from 1 to 9999999 for the global overall tunnel limit.

Timeouts

GSN timeout—Lets you change the default for the maximum period of inactivity before a GSN is removed. The default is 30 minutes. Timeout is in the format

hh

:

mm

:

ss

, where

hh

specifies the hour,

mm

specifies the minutes, and

ss

specifies the seconds. A value 0 means never tear down.

PDP-Context timeout—Lets you change the default for the maximum period of inactivity before receiving the PDP Context for a GTP session. The default is 30 minutes. Timeout is in the format

hh

:

mm

:

ss

, where

hh

specifies the hour,

mm


ss


Request Queue—Lets you change the default for the maximum period of inactivity before receiving the GTP message during a GTP session. The default is 1 minute. Timeout is in the format

hh

:

mm

:

ss

, where

hh

specifies the hour,

mm


ss


Signaling—Lets you change the default for the maximum period of inactivity before a GTP signaling is removed. The default is 30 minutes. Timeout is in the format

hh

:

mm

:

ss

, where

hh

specifies the hour,

mm


ss


Tunnel—Lets you change the default for the maximum period of inactivity for the GTP tunnel.

The default is 1 hour. Timeout is in the format

hh

:

mm

:

ss

, where

hh

specifies the hour,

mm


ss

specifies the seconds. A value 0 means never tear down Request timeout—Specifies the GTP Request idle timeout.

T3-Response timeout—Specifies the maximum wait time for a response before removing the connection.

IMSI Prefix Filtering—Tab that lets you configure the IMSI prefix filtering for the GTP inspect map.

–

Mobile Country Code—Defines the non-zero, three-digit value identifying the mobile country code. One or two-digit entries will be prepended by 0 to create a three-digit value.

–

–

Mobile Network Code—Defines the two or three-digit value identifying the network code.


–


Inspections—Tab that lets you configure the GTP inspect maps.

–

–


Criterion—Shows the criterion of the GTP inspection.

–

–

Value—Shows the value to match in the GTP inspection.


–

–


Add—Opens the Add GTP Inspect dialog box to add an GTP inspection.

–

Edit—Opens the Edit GTP Inspect dialog box to edit an GTP inspection.

40-10


OL-20339-01


–

–

–

Delete—Deletes an GTP inspection.



Modes


GTP Inspection

Firewall Mode

Routed



Multiple

Context

• • • •

System

—

Add/Edit GTP Map

The Add/Edit GTP Inspect dialog box lets you define the match criterion and value for the GTP inspect map.

Fields

•


•



Criterion—Specifies which criterion of GTP traffic to match.

–

–

–

–

Access Point Name—Match on access point name.

Message ID—Match on the message ID.

Message Length—Match on the message length

Version—Match on the version.

•

Access Point Name Criterion Values—Specifies an access point name to be matched. By default, all messages with valid APNs are inspected, and any APN is allowed.

–


–

–



•

–

–

–


Message ID Criterion Values—Specifies the numeric identifier for the message that you want to match. The valid range is 1 to 255. By default, all valid message IDs are allowed.

–


Action—Drop.

Value—Specifies whether value is an exact match or a range.

Equals—Enter a value.

Range—Enter a range of values.

OL-20339-01


40-11


RADIUS Accounting Inspection

•

•

–

Action—Drop packet or limit rate (pps).

–


Message Length Criterion Values—Lets you change the default for the maximum message length for the UDP payload that is allowed.

–

–

Minimum value—Specifies the minimum number of bytes in the UDP payload. The range is from 1 to 65536.

Maximum value—Specifies the maximum number of bytes in the UDP payload. The range is from 1 to 65536.

–

–



Version Criterion Values—Specifies the GTP version for messages that you want to match. The valid range is 0-255. Use 0 to identify Version 0 and 1 to identify Version 1. Version 0 of GTP uses port

3386, while Version 1 uses port 2123. By default all GTP versions are allowed.

–

Value—Specifies whether value is an exact match or a range.

–

–

Equals—Enter a value.

Range—Enter a range of values.



Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—



•

•

RADIUS Accounting Inspection Overview, page 40-13

Select RADIUS Accounting Map, page 40-13

•

•

•

•

Add RADIUS Accounting Policy Map, page 40-14

RADIUS Inspect Map, page 40-14

RADIUS Inspect Map Host, page 40-15

RADIUS Inspect Map Other, page 40-15

40-12


OL-20339-01



RADIUS Accounting Inspection Overview

One of the well known problems is the over-billing attack in GPRS networks. The over-billing attack can cause consumers anger and frustration by being billed for services that they have not used. In this case, a malicious attacker sets up a connection to a server and obtains an IP address from the SGSN.

When the attacker ends the call, the malicious server will still send packets to it, which gets dropped by the GGSN, but the connection from the server remains active. The IP address assigned to the malicious attacker gets released and reassigned to a legitimate user who will then get billed for services that the attacker will use.

RADIUS accounting inspection prevents this type of attack by ensuring the traffic seen by the GGSN is legitimate. With the RADIUS accounting feature properly configured, the security appliance tears down a connection based on matching the Framed IP attribute in the Radius Accounting Request Start message with the Radius Accounting Request Stop message. When the Stop message is seen with the matching

IP address in the Framed IP attribute, the security appliance looks for all connections with the source matching the IP address.

You have the option to configure a secret pre-shared key with the RADIUS server so the security appliance can validate the message. If the shared secret is not configured, the security appliance does not need to validate the source of the message and will only check that the source IP address is one of the configured addresses allowed to send the RADIUS messages.

Note

When using RADIUS accounting inspection with GPRS enabled, theadaptive security appliance checks for the 3GPP-Session-Stop-Indicator in the Accounting Request STOP messages to properly handle secondary PDP contexts. Specifically, the adaptive security appliance requires that the Accounting

Request STOP messages include the 3GPP-SGSN-Address attribute before it will temrinate the user sessions and all associated connections. Some third-party GGSNs might not send this attribute by default.

Select RADIUS Accounting Map

The Select RADIUS Accounting Map dialog box lets you select a defined RADIUS accounting map or define a new one.

Fields

•

Add—Lets you add a new RADIUS accounting map.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

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Add RADIUS Accounting Policy Map

The Add RADIUS Accounting Policy Map dialog box lets you add the basic settings for the RADIUS accounting map.

Fields

•

Name—Enter the name of the previously configured RADIUS accounting map.

•

Description—Enter the description of the RADIUS accounting map, up to 100 characters in length.

•

Host Parameters tab:

–

Host IP Address—Specify the IP address of the host that is sending the RADIUS messages.

–

–

Key: (optional)—Specify the key.

Add—Adds the host entry to the Host table.

•

–

Delete—Deletes the host entry from the Host table.

Other Parameters tab:

–

–

Attribute Number—Specify the attribute number to validate when an Accounting Start is received.

Add—Adds the entry to the Attribute table.

–

–

Delete—Deletes the entry from the Attribute table.

Send response to the originator of the RADIUS message—Sends a message back to the host from which the RADIUS message was sent.

–

•

Enforce timeout—Enables the timeout for users.

Users Timeout—Timeout for the users in the database (hh:mm:ss).

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

RADIUS Inspect Map

The RADIUS pane lets you view previously configured RADIUS application inspection maps. A

RADIUS map lets you change the default configuration values used for RADIUS application inspection.

You can use a RADIUS map to protect against an overbilling attack.

Fields

•

Name—Enter the name of the inspect map, up to 40 characters in length.

•

Description—Enter the description of the inspect map, up to 200 characters in length.

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•

•

•

RADIUS Inspect Maps—Table that lists the defined RADIUS inspect maps. The defined inspect maps are also listed in the RADIUS area of the Inspect Maps tree.

Add—Adds the new RADIUS inspect map to the defined list in the RADIUS Inspect Maps table and to the RADIUS area of the Inspect Maps tree. To configure the new RADIUS map, select the

RADIUS entry in Inspect Maps tree.

Delete—Deletes the application inspection map selected in the RADIUS Inspect Maps table and from the RADIUS area of the Inspect Maps tree.

Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

RADIUS Inspect Map Host

The RADIUS Inspect Map Host Parameters pane lets you configure the host parameter settings for the inspect map.

Fields

•

Name—Shows the name of the previously configured RADIUS accounting map.

•

•


Host Parameters—Lets you configure host parameters.

•

•

–

–

Host IP Address—Specify the IP address of the host that is sending the RADIUS messages.

Key: (optional)—Specify the key.

Add—Adds the host entry to the Host table.

Delete—Deletes the host entry from the Host table.

Modes


Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

RADIUS Inspect Map Other

The RADIUS Inspect Map Other Parameters pane lets you configure additional parameter settings for the inspect map.

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RSH Inspection


Fields

•

Name—Shows the name of the previously configured RADIUS accounting map.

•


•

Other Parameters—Lets you configure additional parameters.

–

Send response to the originator of the RADIUS message—Sends a message back to the host from which the RADIUS message was sent.

–

Enforce timeout—Enables the timeout for users.

Users Timeout—Timeout for the users in the database (hh:mm:ss).

–

–

Enable detection of GPRS accounting—Enables detection of GPRS accounting. This option is only available when GTP/GPRS license is enabled.

Validate Attribute—Attribute information.

Attribute Number—Specify the attribute number to validate when an Accounting Start is received.

Add—Adds the entry to the Attribute table.

Delete—Deletes the entry from the Attribute table.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

RSH Inspection

RSH inspection is enabled by default. The RSH protocol uses a TCP connection from the RSH client to the RSH server on TCP port 514. The client and server negotiate the TCP port number where the client listens for the STDERR output stream. RSH inspection supports NAT of the negotiated port number if necessary.

SNMP Inspection


•

•

•

SNMP Inspection Overview, page 40-17

“Select SNMP Map” section on page 40-17

“SNMP Inspect Map” section on page 40-17

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SNMP Inspection

SNMP Inspection Overview

SNMP application inspection lets you restrict SNMP traffic to a specific version of SNMP. Earlier versions of SNMP are less secure; therefore, denying certain SNMP versions may be required by your security policy. The adaptive security appliance can deny SNMP versions 1, 2, 2c, or 3. You control the versions permitted by creating an SNMP map.

You then apply the SNMP map when you enable SNMP inspection according to the “Configuring

Application Layer Protocol Inspection” section on page 36-5 .

Select SNMP Map

The Select SNMP Map dialog box lets you select or create a new SNMP map. An SNMP map lets you change the configuration values used for SNMP application inspection. The Select SNMP Map table provides a list of previously configured maps that you can select for application inspection.

Fields

•

Use the default SNMP inspection map—Specifies to use the default SNMP map.

•

Select an SNMP map for fine control over inspection

—


•


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

SNMP Inspect Map

The SNMP pane lets you view previously configured SNMP application inspection maps. An SNMP map lets you change the default configuration values used for SNMP application inspection.

Fields

•

Map Name—Lists previously configured application inspection maps. Select a map and click

Edit

to view or change an existing map.

•

Add—Configures a new SNMP inspect map.

•

•

Edit—Edits the selected SNMP entry in the SNMP Inspect Maps table.

Delete—Deletes the inspect map selected in the SNMP Inspect Maps table.

Modes


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40-17

XDMCP Inspection


Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

Add/Edit SNMP Map

The Add/Edit SNMP Map dialog box lets you create a new SNMP map for controlling SNMP application inspection.

Fields

•

SNMP Map Name—Defines the name of the application inspection map.

•

SNMP version 1—Enables application inspection for SNMP version 1.

•

•

•

SNMP version 2 (party based)—Enables application inspection for SNMP version 2.

SNMP version 2c (community based)—Enables application inspection for SNMP version 2c.

SNMP version 3—Enables application inspection for SNMP version 3.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—


XDMCP inspection is enabled by default; however, the XDMCP inspection engine is dependent upon proper configuration of the

established

command.

XDMCP is a protocol that uses UDP port 177 to negotiate X sessions, which use TCP when established.

For successful negotiation and start of an XWindows session, the adaptive security appliance must allow the TCP back connection from the Xhosted computer. To permit the back connection, use the

established

command on the adaptive security appliance. Once XDMCP negotiates the port to send the display, The

established

command is consulted to verify if this back connection should be permitted.

During the XWindows session, the manager talks to the display Xserver on the well-known port 6000

|

n. Each display has a separate connection to the Xserver, as a result of the following terminal setting.

setenv DISPLAY Xserver:n where

n

is the display number.

When XDMCP is used, the display is negotiated using IP addresses, which the adaptive security appliance can NAT if needed. XDCMP inspection does not support PAT.

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P

A R T

9

Configuring Unified Communications

C H A P T E R

41

Information About Cisco Unified

Communications Proxy Features

This chapter describes how to configure the adaptive security appliance for Cisco Unified

Communications Proxy features.


•

Information About the Adaptive Security Appliance in Cisco Unified Communications, page 41-1

•

•

TLS Proxy Applications in Cisco Unified Communications, page 41-3

Licensing for Cisco Unified Communications Proxy Features, page 41-4

Information About the Adaptive Security Appliance in Cisco

Unified Communications

This section describes the Cisco UC Proxy features on the Cisco ASA 5500 series appliances. The purpose of a proxy is to terminate and reoriginate connections between a client and server. The proxy delivers a range of security functions such as traffic inspection, protocol conformance, and policy control to ensure security for the internal network. An increasingly popular function of a proxy is to terminate encrypted connections in order to apply security policies while maintaining confidentiality of connections. The Cisco ASA 5500 Series appliances are a strategic platform to provide proxy functions for unified communications deployments.

The Cisco UC Proxy includes the following solutions:

Phone Proxy: Secure remote access for Cisco encrypted endpoints, and VLAN traversal for Cisco softphones

The phone proxy feature enables termination of Cisco SRTP/TLS-encrypted endpoints for secure remote access. The phone proxy allows large scale deployments of secure phones without a large scale VPN remote access hardware deployment. End-user infrastructure is limited to just the IP endpoint, without

VPN tunnels or hardware.

The Cisco adaptive security appliance phone proxy is the replacement product for the Cisco Unified

Phone Proxy. Additionally, the phone proxy can be deployed for voice/data VLAN traversal for softphone applications. Cisco IP Communicator (CIPC) traffic (both media and signaling) can be proxied through the adaptive security appliance, thus traversing calls securely between voice and data

VLANs.

For information about the differences between the TLS proxy and phone proxy, go to the following URL for Unified Communications content, including TLS Proxy vs. Phone Proxy white paper:

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Chapter 41 Information About Cisco Unified Communications Proxy Features

Information About the Adaptive Security Appliance in Cisco Unified Communications

http://www.cisco.com/go/secureuc

TLS Proxy: Decryption and inspection of Cisco Unified Communications encrypted signaling

End-to-end encryption often leaves network security appliances “blind” to media and signaling traffic, which can compromise access control and threat prevention security functions. This lack of visibility can result in a lack of interoperability between the firewall functions and the encrypted voice, leaving businesses unable to satisfy both of their key security requirements.

The adaptive security appliance is able to intercept and decrypt encrypted signaling from Cisco encrypted endpoints to the Cisco Unified Communications Manager (Cisco UCM), and apply the required threat protection and access control. It can also ensure confidentiality by re-encrypting the traffic onto the Cisco UCM servers.

Typically, the adaptive security appliance TLS Proxy functionality is deployed in campus unified communications network. This solution is ideal for deployments that utilize end to end encryption and firewalls to protect Unified Communications Manager servers.

Mobility Proxy: Secure connectivity between Cisco Unified Mobility Advantage server and Cisco Unified Mobile

Communicator clients

Cisco Unified Mobility solutions include the Cisco Unified Mobile Communicator (Cisco UMC), an easy-to-use software application for mobile handsets that extends enterprise communications applications and services to mobile phones and the Cisco Unified Mobility Advantage (Cisco UMA) server. The Cisco Unified Mobility solution streamlines the communication experience, enabling single number reach and integration of mobile endpoints into the Unified Communications infrastructure.

The security appliance acts as a proxy, terminating and reoriginating the TLS signaling between the

Cisco UMC and Cisco UMA. As part of the proxy security functionality, inspection is enabled for the

Cisco UMA Mobile Multiplexing Protocol (MMP), the protocol between Cisco UMC and Cisco UMA.

Presence Federation Proxy: Secure connectivity between Cisco Unified Presence servers and Cisco/Microsoft

Presence servers

Cisco Unified Presence solution collects information about the availability and status of users, such as whether they are using communication devices, such as IP phones at particular times. It also collects information regarding their communications capabilities, such as whether web collaboration or video conferencing is enabled. Using user information captured by Cisco Unified Presence, applications such as Cisco Unified Personal Communicator and Cisco UCM can improve productivity by helping users connect with colleagues more efficiently through determining the most effective way for collaborative communication.

Using the adaptive security appliance as a secure presence federation proxy, businesses can securely connect their Cisco Unified Presence (Cisco UP) servers to other Cisco or Microsoft Presence servers, enabling intra-enterprise communications. The security appliance terminates the TLS connectivity between the servers, and can inspect and apply policies for the SIP communications between the servers.

Cisco Intercompany Media Engine Proxy: Secure connectivity between Cisco UCM servers in different enterprises for IP Phone traffic

As more unified communications are deployed within enterprises, cases where business-to-business calls utilize unified communications on both sides with the Public Switched Network (PSTN) in the middle become increasingly common. All outside calls go over circuits to telephone providers and from there are delivered to all external destinations.

The Cisco Intercompany Media Engine gradually creates dynamic, encrypted VoIP connections between businesses, so that a collection of enterprises that work together end up looking like one giant business with secure VoIP interconnections between them.

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TLS Proxy Applications in Cisco Unified Communications

There are three components to a Cisco Intercompany Media Engine deployment within an enterprise: a

Cisco Intercompany Media Engine server, a call agent (the Cisco Unified Communications Manager) and an adaptive security appliance running the Cisco Intercompany Media Engine Proxy.

The adaptive security appliance provides perimeter security by encrypting signaling connections between enterprises and preventing unathorized calls. An adaptive security appliance running the Cisco

Intercompany Media Engine Proxy can either be deployed as an Internet firewall or be designated as a

Cisco Intercompany Media Engine Proxy and placed in the DMZ, off the path of the regular Internet traffic.

TLS Proxy Applications in Cisco Unified Communications

Table 41-1

shows the Cisco Unified Communications applications that utilize the TLS proxy on the adaptive security appliance.

Table 41-1 TLS Proxy Applications and the Security Appliance

Application

Phone Proxy and TLS Proxy

TLS Client

IP phone

Mobility Proxy Cisco UMC

Presence

Federation

Proxy

TLS Server

Cisco UCM

Cisco UMA

Cisco UP or

MS LCS/OCS

Cisco UP or

MS LCS/OCS

Client

Authentication

Yes

No

Yes

Security

Appliance

Server Role

Proxy certificate, self-signed or by internal CA

Security

Appliance

Client Role

Local dynamic certificate signed by the adaptive security appliance CA

(might not need certificate for phone proxy application)

Any static configured certificate

Using the

Cisco UMA private key or certificate impersonation

Proxy certificate, self-signed or by internal CA

Using the

Cisco UP private key or certificate impersonation

The adaptive security appliance supports TLS proxy for various voice applications. For the phone proxy, the TLS proxy running on the adaptive security appliance has the following key features:

•

•

The adaptive security appliance forces remote IP phones connecting to the phone proxy through the

Internet to be in secured mode even when the Cisco UCM cluster is in non-secure mode.

The TLS proxy is implemented on the adaptive security appliance to intercept the TLS signaling from IP phones.

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Licensing for Cisco Unified Communications Proxy Features

•

•

•

The TLS proxy decrypts the packets, sends packets to the inspection engine for NAT rewrite and protocol conformance, optionally encrypts packets, and sends them to Cisco UCM or sends them in clear text if the IP phone is configured to be in nonsecure mode on the Cisco UCM.

The adaptive security appliance acts as a media terminator as needed and translates between SRTP and RTP media streams.

The TLS proxy is a transparent proxy that works based on establishing trusted relationship between the TLS client, the proxy (the adaptive security appliance), and the TLS server.

For the Cisco Unified Mobility solution, the TLS client is a Cisco UMA client and the TLS server is a

Cisco UMA server. The adaptive security appliance is between a Cisco UMA client and a Cisco UMA server. The mobility proxy (implemented as a TLS proxy) for Cisco Unified Mobility allows the use of an imported PKCS-12 certificate for server proxy during the handshake with the client. Cisco UMA clients are not required to present a certificate (no client authentication) during the handshake.

For the Cisco Unified Presence solution, the adaptive security appliance acts as a TLS proxy between the Cisco UP server and the foreign server. This allows the adaptive security appliance to proxy TLS messages on behalf of the server that initiates the TLS connection, and route the proxied TLS messages to the client. The adaptive security appliance stores certificate trustpoints for the server and the client, and presents these certificates on establishment of the TLS session.


The Cisco Unified Communications proxy features supported by the adaptive security appliance require a Unified Communications Proxy license:

•

•

•

•

Phone proxy

TLS proxy for encrypted voice inspection

Presence federation proxy

Intercompany media engine proxy

Model

ASA 5505

ASA 5510

ASA 5520

ASA 5540

Note

In Version 8.2(2) and later, the Mobility Advantage proxy no longer requires a Unified Communications

Proxy license.

The following table shows the Unified Communications Proxy license details by platform for the phone proxy, TLS proxy for encrypted voice inspection, and presence federation proxy:


Base License and Security Plus License: 2 sessions

1

.

Optional license: 24 sessions.


1

.

Optional licenses: 24, 50, or 100 sessions.

Base License: 2 sessions

1

.

Optional licenses: 24, 50, 100, 250, 500, 750, or 1000 sessions.


1

.

Optional licenses: 24, 50, 100, 250, 500, 750, 1000, or 2000 sessions.

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OL-20339-01



Model

ASA 5550

ASA 5580



1

.

Optional licenses: 24, 50, 100, 250, 500, 750, 1000, 2000, or 3000 sessions.


1

.

Optional licenses: 24, 50, 100, 250, 500, 750, 1000, 2000, 3000, 5000, or 10,000 sessions.

2

1.

Phone Proxy, Presence Federation Proxy, and Encrypted Voice Inspection applications use TLS proxy sessions for their connections. Each TLS proxy session is counted against the UC license limit. All of these applications are licensed under the UC Proxy umbrella, and can be mixed and matched. Some applications might use multiple sessions for a connection. For example, if you configure a phone with a primary and backup Cisco Unified

Communications Manager, there are 2 TLS proxy connections, so 2 UC Proxy sessions are used.

Note

: Mobility Advantage Proxy does not require a license, and its TLS proxy sessions do not count towards the UC license limit.


- For license part numbers ending in “K8” (for example, licenses under 250 users), TLS proxy sessions are limited to 1000.

- For license part numbers ending in “K9” (for example, licenses 250 users or larger), the TLS proxy limit depends on your configuration and the platform model. To configure the TLS proxy limit, use the Configuration > Firewall > Unified Communications > TLS Proxy pane.

Note

: K8 and K9 refer to whether the license is restricted for export: K8 is unrestricted, and K9 is restricted.


- For K8 licenses, SRTP sessions are limited to 250.

- For K9 licenses, there is not limit.

Note

: Only calls that require encryption/decryption for media are counted towards the SRTP limit; if passthrough is set for the call, even if both legs are

SRTP, they do not count towards the limit.

2.


Table 41-2

shows the default and maximum TLS session details by platform.

Table 41-2 Default and Maximum TLS Sessions on the Security Appliance

Security Appliance Platform

ASA 5505

ASA 5510

ASA 5520

ASA 5540

ASA 5550

ASA 5580

Default TLS Sessions

10

100

300

1000

2000

4000

Maximum TLS Sessions

80

200

1200

4500

4500

13,000

The following table shows the Unified Communications Proxy license details by platform for intercompany media engine proxy:

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41-5


Model

All models



Intercompany Media Engine license.

When you enable the Intercompany Media Engine (IME) license, you can use TLS proxy sessions up to the platform limit. If you also install the Unified Communications (UC) license, then the sessions available for UC are also available for IME sessions. For example, if the platform limit is 1000 TLS proxy sessions, and you purchase a 750-session UC license, then the first 250 IME sessions do not affect the sessions available for UC. If you need more than 250 sessions for IME, then the remaining

750 sessions of the platform limit are used on a first-come, first-served basis by UC and IME.

The maximum number of IME sessions you can use depends on the TLS proxy session limit:

•

Note


For a license part number ending in “K9”, the TLS proxy limit depends on your configuration and the platform model. To configure the TLS proxy limit, use the Configuration > Firewall >

Unified Communications > TLS Proxy pane.K8 and K9 refer to whether the license is restricted for export: K8 is unrestricted, and K9 is restricted.


•

•

Note




For more information about licensing, see

Chapter 4, “Managing Feature Licenses.”

41-6


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C H A P T E R

42

Using the Cisco Unified Communication Wizard


Communications Proxy features.


•

•

•

•

•

Information the Cisco Unified Communication Wizard, page 42-1

Licensing Requirements for the Unified Communication Wizard, page 42-3


Configuring the Mobility Advantage by using the Unified Communication Wizard, page 42-4

•

•

Configuring the Presence Federation Proxy by using the Unified Communication Wizard, page 42-7

Configuring the UC-IME by using the Unified Communication Wizard, page 42-10

Working with Certificates in the Unified Communication Wizard, page 42-17

Information the Cisco Unified Communication Wizard

Note

The Unified Communication Wizard is supported for the adaptive security appliance version 8.3(1) and later.

The Unified Communication Wizard assists you in configuring the following Unified Communications proxies on the adaptive security appliance:

•

Cisco Mobility Advantage Proxy

See

Configuring the Mobility Advantage by using the Unified Communication Wizard, page 42-4

.

•

•

Cisco Presence Federation Proxy

See

Configuring the Presence Federation Proxy by using the Unified Communication Wizard, page 42-7

.

Cisco Intercompany Media Engine Proxy

See

Configuring the UC-IME by using the Unified Communication Wizard, page 42-10 .

The wizard simplifies the configuration of the Unified Communications proxies in the following ways:

•

You enter all required data in the wizard steps. You are not required to navigate various ASDM screens to configure the Unified Communications proxies.


42-1 OL-20339-01

Chapter 42 Using the Cisco Unified Communication Wizard

Information the Cisco Unified Communication Wizard

•

•

The wizard displays network diagrams to illustrate data collection.

To access the Unified Communication Wizard, choose one of the following paths in the main ASDM application window:

•

The wizard generates configuration settings for the Unified Communications proxies where possible, automatically, without requiring you to enter data. For example, the wizard configures the required access lists, IP address translation (NAT and PAT) statements, self-signed certificates, TLS proxies, and application inspection.

•

Wizards > Unified Communication Wizard

.

Configuration > Firewall > Unified Communications,

and then click

Unified Communication

Wizard

.

Mobility Advantage Proxy: Secure connectivity between Cisco Mobility Advantage server and Cisco Unified

Mobile Communicator clients

Cisco Mobility Advantage solutions include the Cisco Unified Mobile Communicator (Cisco UMC), an easy-to-use software application for mobile handsets that extends enterprise communications applications and services to mobile phones and the Cisco Unified Mobility Advantage (Cisco UMA) server. The Cisco Mobility Advantage solution streamlines the communication experience, enabling single number reach and integration of mobile endpoints into the Unified Communications infrastructure.

The security appliance acts as a proxy, terminating and reoriginating the TLS signaling between the

Cisco UMC and Cisco UMA. As part of the proxy security functionality, inspection is enabled for the

Cisco UMA Mobile Multiplexing Protocol (MMP), the protocol between Cisco UMC and Cisco UMA.

Presence Federation Proxy: Secure connectivity between Cisco Unified Presence servers and Cisco/Microsoft

Presence servers

Cisco Unified Presence solution collects information about the availability and status of users, such as whether they are using communication devices, such as IP phones at particular times. It also collects information regarding their communications capabilities, such as whether web collaboration or video conferencing is enabled. Using user information captured by Cisco Unified Presence, applications such as Cisco Unified Personal Communicator and Cisco UCM can improve productivity by helping users connect with colleagues more efficiently through determining the most effective way for collaborative communication.

Using the adaptive security appliance as a secure presence federation proxy, businesses can securely connect their Cisco Unified Presence (Cisco UP) servers to other Cisco or Microsoft Presence servers, enabling intra-enterprise communications. The security appliance terminates the TLS connectivity between the servers, and can inspect and apply policies for the SIP communications between the servers.

Cisco Intercompany Media Engine Proxy: Secure connectivity between Cisco UCM servers in different enterprises for IP Phone traffic

As more unified communications are deployed within enterprises, cases where business-to-business calls utilize unified communications on both sides with the Public Switched Network (PSTN) in the middle become increasingly common. All outside calls go over circuits to telephone providers and from there are delivered to all external destinations.

The Cisco Intercompany Media Engine (UC-IME) gradually creates dynamic, encrypted VoIP connections between businesses, so that a collection of enterprises that work together end up looking like one giant business with secure VoIP interconnections between them.

There are three components to a Cisco Intercompany Media Engine deployment within an enterprise: a

Cisco Intercompany Media Engine server, a call agent (the Cisco Unified Communications Manager) and an adaptive security appliance running the Cisco Intercompany Media Engine Proxy.


42-2 OL-20339-01


Licensing Requirements for the Unified Communication Wizard

The adaptive security appliance provides perimeter security by encrypting signaling connections between enterprises and preventing unauthorized calls. An adaptive security appliance running the Cisco

Intercompany Media Engine Proxy can either be deployed as an Internet firewall or be designated as a

Cisco Intercompany Media Engine Proxy and placed in the DMZ, off the path of the regular Internet traffic.

Licensing Requirements for the Unified Communication Wizard

To run the Unified Communication Wizard in ASDM, you require the following license:

Model

All models


Base License

However, to run each of the Unified Communications proxy features created by the wizard, you must have the appropriate Unified Communications Proxy licenses.

The Cisco Unified Communications proxy features supported by the adaptive security appliance require a Unified Communications Proxy license:

•

•

TLS proxy for encrypted voice inspection

Presence Federation Proxy

•


See

Licensing for Cisco Unified Communications Proxy Features, page 41-4 for more information.

Note

The Cisco Intercompany Media Engine Proxy does not appear as an option in the Unified

Communication Wizard unless the license required for this proxy is installed on the adaptive security appliance.




Supported in all modes (single context, multicontext, and transparent mode).


Supported in routed firewall mode only.

IPv6 Guidelines

Supports IPv6 addresses.


Using the Unified Communication Wizard to create the Unified Communications proxies has the following limitations and requirements:

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Configuring the Mobility Advantage by using the Unified Communication Wizard

•

•

•

•

•

You must configure at least two interfaces on the adaptive security appliance to use the UC Wizard to configure a Unified Communications proxy.

For all Unified Communications proxies to function correctly, you must synchronize the clock on the adaptive security appliance and all servers associated with each proxy, such as the Cisco Unified

Communication Manager server, the Cisco Mobility Advantage server, the Cisco Unified Presence server, and the Cisco Intercompany Media Engine server.

When you configure the Cisco Intercompany Media Engine Proxy for an off-path deployment, you must ensure that the public IP addresses and ports of the Cisco Unified Communications Manager servers and the public IP address for the media termination address are accessible from the Internet.

The summary page of the Unified Communication Wizard reminds you of the requirements.

If the adaptive security appliance on which you configure the Cisco Mobility Advantage Proxy and the Cisco Presence Federation Proxy is located behind another firewall, you must ensure that the public IP addresses for the Cisco Mobility Advantage server and the Cisco Unified Presence server are accessible from the Internet.

If you use the Unified Communication Wizard to create to the Presence Federation Proxy and the

Cisco Intercompany Media Engine Proxy, you might be required to adjust the configuration of the

access lists created automatically by the wizard for each proxy. See Chapter 46, “Configuring Cisco

Unified Presence” and

Chapter 47, “Configuring Cisco Intercompany Media Engine Proxy” ,

respectively, for information about the access list requirements required by each proxy.

Configuring the Mobility Advantage by using the Unified

Communication Wizard

Note


The Unified Communication wizard guides you through the steps to configure the Mobility Advantage proxy. Choose

Wizards

>

Unified Communication Wizard

from the menu. The Unified

Communication Wizard opens. Click the Cisco Mobility Advantage Proxy radio button under the

Remote Access section.

When using the wizard to create the Mobility Advantage proxy, ASDM automatically creates the necessary TLS proxies, enables MMP inspection for the Mobility Advantage traffic, generates address translation (NAT) statements, and creates the access rules that are necessary to allow traffic between the

Cisco Mobility Advantage server and the mobility clients.

The following steps provide the high-level overview for configuring the Mobility Advantage proxy:

Step 1

Step 2

Specify settings to define the private and public network topology, such the public and private network interfaces, and the IP addresses of the Cisco Mobility Advantage server. See

Configuring the Topology for the Cisco Mobility Advantage Proxy, page 42-5 .

Configure the certificates that are exchanged between the Cisco Mobility Advantage server and the adaptive security appliance. See

Configuring the Server-Side Certificates for the Cisco Mobility

Advantage Proxy, page 42-5

.

42-4


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Step 3

Configure the client-side certificate management, namely the certificates that are exchanged between the

Unified Mobile Communicator clients and the adaptive security appliance. See

Configuring the

Client-Side Certificates for the Cisco Mobility Advantage Proxy, page 42-6

.

The wizard completes by displaying a summary of the configuration created for Mobility Advantage

Proxy.

Configuring the Topology for the Cisco Mobility Advantage Proxy

When configuring the Mobility Advantage Proxy, you specify settings to define the private and public network topology, such the private and public network interfaces, and the private and public IP addresses of the Cisco Mobility Advantage server.

The values that you specify in this page generate the following configuration settings for the Mobility

Advantage Proxy:

•

•

•

Static PAT for the Cisco Mobility Advantage server

Static NAT for Cisco Unified Mobile Communicator clients if the Enable address translation for

Mobility clients check box is checked.

Access lists to allow Cisco Unified Mobile Communicator clients to access the Cisco Mobility

Advantage server

Step 1

Step 2

Step 3

Step 4

Step 5

In the Private Network area, choose the interface from the drop-down list.

In the Unified MA Server area, enter the private and public IP address for the Cisco Mobility Advantage server. Entering ports for these IP addresses is optional. By default port number 5443 is entered, which is the default TCP port for MMP inspection.

In the Public Network area, choose an interface from the drop-down list.

The proxy uses this interface for configuring static PAT for the Cisco Mobility Advantage server and the access lists to allow Cisco Unified Mobile Communicator clients to access the Cisco Mobility Advantage server.

To configure whether address translation (NAT) is used by Cisco Unified Mobile Communicator clients, check the

Enable address translation for Mobility clients

check box and choose whether to use the IP address of the public interface or whether to enter an IP address.

Click

Next

.

Configuring the Server-Side Certificates for the Cisco Mobility Advantage

Proxy

A trusted relationship between the adaptive security appliance and the Cisco UMA server can be established with self-signed certificates. The adaptive security appliance's identity certificate is exported, and then uploaded on the Cisco UMA server truststore. The Cisco UMA server certificate is downloaded, and then uploaded on the adaptive security appliance truststore.

The supports using self-signed certificates only at this step.

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42-5



Step 1

In the ASA’s Identity Certificate area, click

Generate and Export ASA’s Identity Certificate

.

An information dialog boxes appear indicating that the enrollment seceded. In the Enrollment Status dialog box, click

OK

. The Export certificate dialog box appears.

Note •

•

If an identity certificate for the adaptive security appliance has already been created, the button in this area appears as

Export ASA’s Identity Certificate

and the Export certificate dialog box immediately appears.

When using the wizard to configure the Cisco Mobility Advantage proxy, the wizard only supports installing self-signed certificates.

Step 2

Step 3

Step 4

Step 5

Export the identity certificate generated by the wizard for the adaptive security appliance. See

Exporting an Identity Certificate, page 42-17 .

In the Unified MA Server’s Certificate area, click

Install Unified MA Server’s Certificate

. The Install

Certificate dialog appears.

Locate the file containing the Cisco Mobility Advantage server certificate or paste the certificate details

in the dialog box. See Installing a Certificate, page 42-18

.

Click

Next

.

Note

See the Cisco Mobility Advantage server documentation for information on how to export the certificate for this server.

Configuring the Client-Side Certificates for the Cisco Mobility Advantage Proxy

To establish a trust relationship between the Cisco Unified Mobile Communicator (UMC) clients and the adaptive security appliance, the adaptive security appliance uses a CA-signed certificate that is configured with the Cisco Mobility Advantage server’s FQDN (also referred to as certificate impersonation).

In the Client-Side Certificate Management page, you enter both the intermediate CA certificate (if applicable, as in the cases of Verisign) and the signed adaptive security appliance identity certificate.

Note

If the adaptive security appliance already has a signed identity certificate, you can skip

Step 1 in this

procedure and proceed directly to

Step 2 .

Step 1


Generate CSR

. The CSR parameters dialog box appears.

For information about specifying additional parameters for the certificate signing request (CSR), see

Generating a Certificate Signing Request (CSR) for a Unified Communications Proxy, page 42-18 .

Information dialog boxes appear indicating that the wizard is delivering the settings to the adaptive security appliance and retrieving the certificate key pair information. The Identity Certificate Request dialog box appears.

42-6


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Configuring the Presence Federation Proxy by using the Unified Communication Wizard

Step 2

Step 3

Step 4

For information about saving the CSR that was generated and submitting it to a CA, see Saving the

Identity Certificate Request, page 42-19 .

Click

Install ASA’s Identity Certificate

. Install the certificate. See

Installing the ASA Identity

Certificate on the Mobility Advantage Server, page 42-20 .

Click

Install Root CA’s Certificate

. The Install Certificate dialog box appears. Install the certificate.

See

Installing a Certificate, page 42-18 .

Click

Next

.


Proxy.

Configuring the Presence Federation Proxy by using the Unified


Note


To configure the Cisco Unified Presence proxy by using ASDM, choose

Wizards

>

Unified


from the menu. The Unified Communication Wizard opens. From the first page, select the Cisco Unified Presence Proxy option under the Business-to-Business section.

When using the wizard to create the Cisco Presence Federation proxy, ASDM automatically creates the necessary TLS proxies, enables SIP inspection for the Presence Federation traffic, generates address translation (static PAT) statements for the local Cisco Unified Presence server, and creates access lists to allow traffic between the local Cisco Unified Presence server and remote servers.

The following steps provide the high-level overview for configuring the Presence Federation Proxy:

Step 1

Step 2

Step 3

Specify settings to define the private and public network topology, such the private and public IP address of the Presence Federation server. See

Configuring the Topology for the Cisco Presence Federation

Proxy, page 42-8 .

Configure the local-side certificate management, namely the certificates that are exchanged between the local Unified Presence Federation server and the adaptive security appliance. See

Configuring the

Local-Side Certificates for the Cisco Presence Federation Proxy, page 42-8

.

Configure the remote-side certificate management, namely the certificates that are exchanged between the remote server and the adaptive security appliance. See

Configuring the Remote-Side Certificates for the Cisco Presence Federation Proxy, page 42-9 .

The wizard completes by displaying a summary of the configuration created for the Presence Federation proxy.

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42-7



Configuring the Topology for the Cisco Presence Federation Proxy

When configuring the Presence Federation Proxy, you specify settings to define the private and public network topology, such the private and public network interfaces, and the private and public IP addresses of the Cisco Unified Presence server.

The values that you specify in this page generate the following configuration settings for the Presence

Federation Proxy:

•

•

Static PAT for the local Cisco Unified Presence server

Access lists for traffic between the local Cisco Unified Presence server and remote servers

Step 1

Step 2

Step 3

Step 4

In the Private Network area, choose the interface from the drop-down list.

In the Unified Presence Server area, enter the private and public IP address for the Unified Presence server. Entering ports for these IP addresses is optional. By default port number 5061 is entered, which is the default TCP port for SIP inspection.

In the Public Network area, choose the interface of the public network from the drop-down list. The proxy uses this interface for configuring static PAT for the local Cisco Unified Presence server and for configuring access lists to allow remote servers to access the Cisco Unified Presence server.

Click

Next

.

Configuring the Local-Side Certificates for the Cisco Presence Federation

Proxy

Within an enterprise, setting up a trust relationship is achievable by using self-signed certificates. The supports using self-signed certificates only at this step.

Step 1



.

An information dialog box appears indicating that enrollment succeeded. In the Enrollment Status dialog box, click

OK


Note •

•




When using the wizard to configure the Cisco Presence Federation proxy, the wizard only supports installing self-signed certificates.

Step 2

Step 3

Step 4


Exporting an Identity Certificate, page 42-17 .

Local Unified Presence Server’s Certificate area, click

Install Server’s Certificate

. The Install


Locate the file containing the Cisco Unified Presence server certificate or paste the certificate details in the dialog box. See

Installing a Certificate, page 42-18

.

42-8


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Step 5

Click

Next

.

Note

See the Cisco Unified Presence server documentation for information on how to export the certificate for this server.

Configuring the Remote-Side Certificates for the Cisco Presence Federation

Proxy

Establishing a trust relationship across enterprises or across administrative domains is key for federation.

Across enterprises you must use a trusted third-party CA (such as, VeriSign). The security appliance obtains a certificate with the FQDN of the Cisco Unified Presence server (certificate impersonation).

For the TLS handshake, the two entities, namely the local entity and a remote entity, could validate the peer certificate via a certificate chain to trusted third-party certificate authorities. The local entity and the remote entity enroll with the CAs. The adaptive security appliance as the TLS proxy must be trusted by both the local and remote entities. The security appliance is always associated with one of the enterprises. Within that enterprise, the entity and the security appliance authenticate each other by using a self-signed certificate.

To establish a trusted relationship between the security appliance and the remote entity, the security appliance can enroll with the CA on behalf of the Cisco Unified Presence server for the local entity. In the enrollment request, the local entity identity (domain name) is used.

To establish the trust relationship, the security appliance enrolls with the third party CA by using the

Cisco Unified Presence server FQDN as if the security appliance is the Cisco Unified Presence server.

Note


Step 1

in this

procedure and proceed directly to Step 2

.

Step 1

Step 2

Step 3


Generate CSR



Generating a Certificate Signing Request (CSR) for a Unified Communications Proxy, page 42-18

.


For information about saving the CSR that was generated and submitting it to a CA, see Saving the

Identity Certificate Request, page 42-19 .

Click


. See

Installing the ASA Identity Certificate on the Presence

Federation and Cisco Intercompany Media Engine Servers, page 42-21

.

Click

Remote Server’s CA’s Certificate

. The Install Certificate dialog box appears. Install the certificate. See


Note

You must install a root CA certificate for each remote entity that communicates with the adaptive security appliance because different organizations might be using different CAs.

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42-9


Configuring the UC-IME by using the Unified Communication Wizard

Step 4

Click

Next

.

The wizard completes by displaying a summary of the configuration created for the Presence Federation proxy.

Configuring the UC-IME by using the Unified Communication

Wizard

Note


To configure the Cisco Intercompany Media Engine Proxy by using ASDM, choose

Wizards

>

Unified


from the menu. The Unified Communication Wizard opens. From the first page, select the Cisco Intercompany Media Engine Proxy option under the Business-to-Business section and click

Next

.

Note

The Cisco Intercompany Media Engine Proxy does not appear as an option in the Unified

Communication Wizard unless the license required for this proxy is installed on the adaptive security appliance.

When using the wizard to create the Cisco Intercompany Media Engine Proxy, ASDM automatically creates the necessary TLS proxies, enables SIP inspection for Cisco Intercompany Media Engine traffic, generates address translation (static PAT) statements for local Cisco Unified Communications Manager servers, and creates access lists to allow traffic between the local Cisco Unified Communications

Manager servers and the remote servers.

The following steps provide the high-level overview for configuring the Cisco Intercompany Media

Engine Proxy:

Step 1

Step 2

Step 3

Step 4

Step 5

Select the topology of the Cisco Intercompany Media Engine Proxy, namely whether the security appliance is an edge firewall with all Internet traffic flowing through it or whether the security appliance is off the path of the main Internet traffic (referred to as an off-path deployment). See

Configuring the

Topology for the Cisco Intercompany Media Engine Proxy, page 42-11 .

Specify private network settings such as the Cisco UCM IP addresses and the ticket settings. See

Configuring the Private Network Settings for the Cisco Intercompany Media Engine Proxy, page 42-12

.

Specify the public network settings. See

Configuring the Public Network Settings for the Cisco

Intercompany Media Engine Proxy, page 42-13 .

Specify the media termination address settings of the Cisco UMC. See

Configuring the Media

Termination Address for the Cisco Intercompany Media Engine Proxy, page 42-14 .

Configure the local-side certificate management, namely the certificates that are exchanged between the local Cisco Unified Communications Manager servers and the security appliance. See

Configuring the

Local-Side Certificates for the Cisco Intercompany Media Engine Proxy, page 42-15

.

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Step 6

Configure the remote-side certificate management, namely the certificates that are exchanged between the remote server and the adaptive security appliance. This certificate is presented to remote servers so that they can authenticate the adaptive security appliance as a trusted server. See

Configuring the

Remote-Side Certificates for the Cisco Intercompany Media Engine Proxy, page 42-16 .

The wizard completes by displaying a summary of the configuration created for the Cisco Intercompany

Media Engine.

Configuring the Topology for the Cisco Intercompany Media Engine Proxy

Step 1

Step 2

Select the topology of your ICME deployment by click on the following options:

•

All Internet traffic flows through the ASA radio button. This option is also referred to as a basic deployment.

•

This ASA is off the path of the regular Internet traffic. This option is also referred to as an off-path deployment.

Click

Next

.

OL-20339-01

Basic Deployment

In a basic deployment, the Cisco Intercompany Media Engine Proxy sits in-line with the Internet firewall such that all Internet traffic traverses the adaptive security appliance. In this deployment, a single Cisco

UCM or a Cisco UCM cluster is centrally deployed within the enterprise, along with a Cisco

Intercompany Media Engine server (and perhaps a backup). A single Internet connection traverses the adaptive security appliance, which is enabled with the Cisco Intercompany Media Engine Proxy.

The adaptive security appliance sits on the edge of the enterprise and inspects SIP signaling by creating dynamic SIP trunks between enterprises.

Off-path Deployment

In an off path deployment, inbound and outbound Cisco Intercompany Media Engine calls pass through an adaptive security appliance enabled with the Cisco Intercompany Media Engine Proxy. The adaptive security appliance is located in the DMZ and configured to support primarily Cisco Intercompany Media

Engine. Normal Internet facing traffic does not flow through this adaptive security appliance.

For all inbound calls, the signaling is directed to the adaptive security appliance because destined Cisco

UCMs are configured with the global IP address on the adaptive security appliance. For outbound calls, the called party could be any IP address on the Internet; therefore, the adaptive security appliance is configured with a mapping service that dynamically provides an internal IP address on the adaptive security appliance for each global IP address of the called party on the Internet.

Cisco UCM sends all outbound calls directly to the mapped internal IP address on the adaptive security appliance instead of the global IP address of the called party on the Internet. The adaptive security appliance then forwards the calls to the global IP address of the called party.

Note

When you configure the Cisco Intercompany Media Engine for an off-path deployment, you must ensure that the public IP addresses and ports of the Cisco Unified Communications Manager servers and the public IP address for the media termination address are accessible from the Internet. The summary page of the Unified Communication Wizard reminds you of the requirements.


42-11



Configuring the Private Network Settings for the Cisco Intercompany Media

Engine Proxy

When configuring the Cisco Intercompany Media Engine Proxy, you specify settings to define the private network topology, such the private network interface, the IP addresses of the Cisco Unified

Communications servers, and ticket verification. Additionally, when the Cisco Unified Communications servers are operating in secure mode, you specify the X.509 subject name for the Cisco Intercompany

Media Engine Proxy,

The values that you specify in this page generate the following configuration settings for the Cisco

Intercompany Media Engine Proxy:

•

The list of Cisco Unified Communications servers

•

•

The ticket epoch and password used by the Cisco Intercompany Media Engine Proxy

For an off-path deployment only, the mapping service on the same interface as the Cisco Unified

Communications server

Step 1

To configure the Cisco Intercompany Media Engine Proxy as part of a basic deployment, select the interface that connects to the local Cisco Unified Communications servers.

Or

To configure the Cisco Intercompany Media Engine Proxy as part of an off-path deployment, complete the following steps:

a.

b.

From the Listening Interface drop-down list, choose the interface on which the adaptive security appliance listens for the mapping requests.

In the Port field, enter a number between 1024 and 65535 as the TCP port on which the adaptive security appliance listens for the mapping requests. The port number must be 1024 or higher to avoid conflicts with other services on the device, such as Telnet or SSH. By default, the port number is

TCP 8060.

c.

From the UC-IME Interface drop-down list, choose the interface that the adaptive security appliance uses to connect to the remote adaptive security appliance that is enabled with the Cisco

Intercompany Media Engine Proxy.

Note

In a basic and an off-path deployment, all Cisco Unified Communications servers must be on the same interface.

Step 2

Step 3

In the Unified CM Servers area, the wizard displays the private IP address, public IP address, and security mode of any Cisco Unified Communications server configured on the adaptive security appliance. If necessary, click

Add

to add a Cisco Unified Communications server. You must include an entry for each Cisco UCM in the cluster with Cisco Intercompany Media Engine that has a SIP trunk enabled.

In the Ticket Epoch field, enter a integer from 1-255.

The epoch indicates the number of times that password has changed. When the proxy is configured the first time and a password entered for the first time, enter 1 for the epoch integer. Each time you change the password, increment the epoch to indicate the new password. You must increment the epoch value each time your change the password. Typically, you increment the epoch sequentially; however, the security appliance allows you to choose any value when you update the epoch.

If you change the epoch value, the current password is invalidated and you must enter a new password.

42-12


OL-20339-01



Step 4

In the Ticket Password field, enter a minimum of 10 and a maximum of 64 printable character from the

US-ASCII character set. The allowed characters include 0x21 to 0x73 inclusive, and exclude the space character. The ticket password is stored onto flash.

Note

We recommend a password of at least 20 characters. Only one password can be configured at a time.

Step 5

Step 6

Step 7

The epoch and password that you configure on the adaptive security appliance must match the epoch and password configured on the Cisco Intercompany Media Engine server. See the Cisco Intercompany

Media Engine server documentation for information.

In the Confirm Password field, reenter the password.

In the X.509 Subject Name field, enter the distinguished name (DN) of the local enterprise. The name that you enter must match the name configured for the Cisco Unified Communications servers in the cluster. See the Cisco Unified Communications server documentation for information.

Click

Next

.

Adding a Cisco Unified Communications Manager Server for the UC-IME Proxy

You must include an entry for each Cisco UCM in the cluster with Cisco Intercompany Media Engine

Proxy that has a SIP trunk enabled.

Step 1

Step 2

Step 3

Step 4

Step 5

Enter the private IP address and port number (in the range 5000-6000) for the Cisco UCM server.

In the Address Translation area, enter the public IP address for the Cisco UCM server.

If necessary, enter the port number for the public IP address by clicking the Translate address and port radio button and entering a number (in the range 5000-6000) in the Port field.

In the Security Mode area, click the Secure or Non-secure radio button. Specifying secure for Cisco

UCM or Cisco UCM cluster indicates that Cisco UCM or Cisco UCM cluster is initiating TLS.

If you specify that some of the Cisco UCM servers are operating in secure mode, the Unified

Communications Wizard includes a step in the proxy configuration to generate certificates for the local-side communication between the adaptive security appliance and that Cisco UCM server. See

Configuring the Local-Side Certificates for the Cisco Intercompany Media Engine Proxy, page 42-15 .

Click

OK

.

Configuring the Public Network Settings for the Cisco Intercompany Media

Engine Proxy

The public network configuration depends on the deployment scenario you selected in the topology step of this wizard. Specifically, when you are configuring the UC-IME proxy as part of an off-path deployment, this step of the wizard displays fields for address translation, requiring that you specify the private IP address for the UC-IME proxy. Specifying this private IP address, translates IP addresses for inbound traffic.

OL-20339-01


42-13



In an off-path deployment, any existing adaptive security appliance that you have deployed in your environment are not capable of transmitting Cisco Intercompany Media Engine traffic. Therefore, off-path signaling requires that outside addresses translate to an inside (private) IP address. The inside interface address can be used for this mapping service configuration. For the Cisco Intercompany Media

Engine Proxy, the adaptive security appliance creates dynamic mappings for external addresses to the internal IP address.

The values that you specify in this page generate the following configuration settings for the Cisco

Intercompany Media Engine Proxy:

•

Static PAT for the Cisco Unified Communications servers

•

Access lists for traffic between the local and the remote servers

Step 1

Step 2

Step 3

In the Configure public network area, choose an interface from the Interface drop-down list.

When configuring an off-path deployment, in the Address Translation area, specify whether to use the private IP address for the public network.

Or

Click the Specify IP address radio button and enter an IP address in the field.

Click

Next

.

Configuring the Media Termination Address for the Cisco Intercompany Media

Engine Proxy

The data from this step generates the MTA instance to be added to the UC-IME proxy.

For the UC-IME proxy to be fully functional, you must ensure that the public IP address for the media termination address (MTA) is accessible from the Internet. The summary page of the Unified

Communication Wizard reminds you of this requirement.

The MTA IP addresses that you specify must meet specific requirements. See Media Termination

Instance Prerequisites, page 43-5

for information.

Step 1

Step 2

Step 3

In the field for the private IP address, enter the private IP address for the MTA. The IP address of the

MTA must be in within the same subnet as the private interface IP address. The correct subnet range is provided to the right of the field for the private IP address.

In the field for the public IP address, enter the public IP address for the MTA. The IP address of the MTA must be in within the same subnet as the public interface IP address. The correct subnet range is provided to the right of the field for the public IP address.

Click

Next

.

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Configuring the Local-Side Certificates for the Cisco Intercompany Media

Engine Proxy

Completing this step of the wizard generates a self-signed certificate for the adaptive security appliance.

The server proxy certificate is automatically generated using the subject name provided in an earlier step of this wizard.

The wizard supports using self-signed certificates only.

A trusted relationship between the adaptive security appliance and the Cisco UMA server can be established with self-signed certificates. The certificates are used by the security appliance and the Cisco

UCMs to authenticate each other, respectively, during TLS handshakes.

The adaptive security appliance's identity certificate is exported, and then needs to be installed on each

Cisco Unified Communications Manager (UCM) server in the cluster with the proxy and each identity certificate from the Cisco UCMs need to be installed on the security appliance.

This step in the Unified Communications Wizard only appears when the UC-IME proxy that you are creating has at least one secure Cisco Unified Communications Manager server defined. See

Configuring the Topology for the Cisco Intercompany Media Engine Proxy, page 42-11

for information.

Step 1



.

An information dialog boxes appear indicating that the enrollment seceded. In the Enrollment Status dialog box, click

OK


Note •

•




When using the wizard to configure the Cisco Intercompany Media Engine Proxy, the wizard only supports installing self-signed certificates.

Step 2

Step 3

Step 4

Step 5



.

In the Local Unified CM’s Certificate area, click

Install Local Unified CM’s Certificate

. The Install


Locate the file containing the certificate from the Cisco Unified Communications Manager server or paste the certificate details in the dialog box. See

Installing a Certificate, page 42-18 . You must install

the certificate from each Cisco Unified Communications Manager server in the cluster.

Click

Next

.

Note

See the Cisco Intercompany Media Engine server documentation for information on how to export the certificate for this server.

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42-15



Configuring the Remote-Side Certificates for the Cisco Intercompany Media

Engine Proxy

Establishing a trust relationship cross enterprises or across administrative domains is key. Cross enterprises you must use a trusted third-party CA (such as, VeriSign). The adaptive security appliance obtains a certificate with the FQDN of the Cisco Unified Communications Manager server (certificate impersonation).

For the TLS handshake, the two entities could validate the peer certificate via a certificate chain to trusted third-party certificate authorities. Both entities enroll with the CAs. The adaptive security appliance as the TLS proxy must be trusted by both entities. The adaptive security appliance is always associated with one of the enterprises. Within that enterprise, the entity and the adaptive security appliance could authenticate each other via a local CA, or by using self-signed certificates.

To establish a trusted relationship between the adaptive security appliance and the remote entity, the adaptive security appliance can enroll with the CA on behalf of the local enterprise. In the enrollment request, the local Cisco UCM identity (domain name) is used.

To establish the trust relationship, the adaptive security appliance enrolls with the third party CA by using the Cisco Unified Communications Manager server FQDN as if the security appliance is the Cisco

UCM.

Note


Step 1 in this

procedure and proceed directly to

Step 3 .

Step 1

Step 2

Step 3


Generate CSR



Generating a Certificate Signing Request (CSR) for a Unified Communications Proxy, page 42-18 .


For information about saving the CSR that was generated and submitting it to a CA, see

Saving the

Identity Certificate Request, page 42-19

.



.

Installing the ASA

Identity Certificate on the Presence Federation and Cisco Intercompany Media Engine Servers, page 42-21

.

In the Remote Server’s CA’s Certificate area, click

Install Remote Server’s CA’s Certificate

. Installing the root certificates of the CA for the remote servers is necessary so that the adaptive security appliance can determine that the remote servers are trusted.

The Install Certificate dialog box appears. Install the certificate. See


Step 4

Note

You must install the root certificates only when the root certificates for the remote servers are received from a CA other than the one that provided the identity certificate for the adaptive security appliance

Click

Next

.

42-16


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Working with Certificates in the Unified Communication Wizard

The wizard completes by displaying a summary of the configuration created for the Cisco Intercompany

Media Engine.



•

•

•

•

•



Generating a Certificate Signing Request (CSR) for a Unified Communications Proxy, page 42-18

Saving the Identity Certificate Request, page 42-19

•

Installing the ASA Identity Certificate on the Mobility Advantage Server, page 42-20


Engine Servers, page 42-21

Exporting an Identity Certificate

The Cisco Mobility Advantage Proxy, Cisco Presence Federation Proxy, or Cisco Intercompany Media

Engine Proxy require that you export the adaptive security appliance identity certificate to install on the

Cisco Mobility Advantage server, Cisco Presence Federation server, and Cisco Unified Communications server, respectfully.

You use the wizard to export a self-signed identity certificate. The identity certificate has all associated keys and is in PKCS12 format, which is the public key cryptography standard. When configuring a

Unified Communications proxy by using the wizard, you click the Generate and Export ASA’s Identify

Certificate button while in the local-side or server-side certificate management step of the wizard. The

Export certificate dialog box appears.

From the Export certificate dialog box, perform these steps:

Step 1

Step 2

Enter the name of the PKCS12 format file to use in exporting the certificate configuration. Alternatively, click Browse to display the Export ID Certificate File dialog box to find the file to which you want to export the certificate configuration.

Click Export Certificate to export the certificate configuration.

An information dialog box appears informing you that the certificate configuration file has been successfully exported to the location that you specified.

You complete the configuration of the Cisco Mobility Advantage Proxy, Cisco Presence Federation

Proxy, or Cisco Intercompany Media Engine Proxy, you must import the generated adaptive security appliance identify certificate in to the Cisco Mobility Advantage server, Cisco Presence Federation server, and Cisco Unified Communications server, respectfully, depending on which proxy you are configuring.

See the documentation for the for each of these products for information about importing an identity certificate into each.

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42-17



Installing a Certificate

When configuring certificates for the Cisco Mobility Advantage Proxy, the Cisco Presence Federation

Proxy, and Cisco Intercompany Media Engine Proxy, you must install the certificates from the Cisco

Mobility Advantage server, Cisco Presence Federation server, and Cisco Unified Communications

Manager servers, respectively, on the adaptive security appliance. See the documentation for each of these products for information about obtaining the identity certificates from each.

Additionally, when configuring the Cisco Mobility Advantage Proxy, you use the Install Certificate dialog box to install the root certificate received from the certificate authority. The root certificate from the certificate authority is used to sign other certificates. The root certificate is used by the adaptive security appliance to authenticate your signed identity certificate received from the certificate authority.

Note

When using the wizard to configure the Unified Communications proxies, the wizard only supports installing self-signed certificates.

From the Install Certificate dialog box, perform these steps:

Step 1

Step 2

Perform one of the following actions:

•



radio button (this is the default setting). Enter the path and file name, or click

Browse



.

•


Paste certificate in PEM format

radio button. Copy and paste the

PEM format (base64 or hexadecimal) certificate into the area provided.

Click


.

An information dialog box appears informing you that the certificate was installed on the adaptive security appliance successfully.

Generating a Certificate Signing Request (CSR) for a Unified Communications

Proxy

When configuring certificates for the Cisco Mobility Advantage Proxy, Cisco Presence Federation

Proxy, or Cisco Intercompany Media Engine Proxy, you must generate and identity certificate request for the adaptive security appliance.

Note

If the adaptive security appliance already has a signed identity certificate, you do not need to generate a

CSR and can proceed directly to installing this certificate on the adaptive security appliance. See

Installing the ASA Identity Certificate on the Mobility Advantage Server, page 42-20 and

Installing the

ASA Identity Certificate on the Presence Federation and Cisco Intercompany Media Engine Servers, page 42-21

for the steps to install the identity certificate.

The identify certificate that you receive is presented to the following entities for each of the Unified

Communication Proxies:

•

Unified Mobile Communicator clients for the Cisco Mobility Advantage Proxy

42-18


OL-20339-01



•

Remote Presence Federation servers for the Cisco Presence Federation Proxy

•

The remote adaptive security appliancefor the Cisco Intercompany Media Engine Proxy

Before generating the CSR, you can enter additional parameters.

When configuring a Unified Communications proxy by using the wizard, you click the Generate CSR button while in the client-side or remote-side certificate management step of the wizard. The CSR

Parameters dialog box appears.

In the CSR Parameters dialog box, perform the following steps:

Step 1

Step 2

From the Key Pair Size drop-down list, choose the size required for you certificate.

The key size that you select depends on the level of security that you want to configure and on any limitations imposed by the CA from which you are obtaining the certificate. The larger the number that you select, the higher the security level will be for the certificate. Most CAs recommend 2048 for the key modulus size; however, GoDaddy requires a key modulus size of 2048.

In the first field of the Certificate Subject DN section, enter the domain name used by your enterprise or network.

Note

The domain name that you configure for the Cisco Intercompany Media Engine Proxy must match the domain name that set in the local Cisco Unified Communications Manager server; for example, cisco.com. The fully-qualified domain name (FQDN) that you configure for the Cisco

Mobility Advantage Proxy and Cisco Presence Federation Proxy must match the FQDN name set in the Cisco Mobility Advantage server and Cisco Unified Presence server, respectively; for example, myhost.cisco.com

Step 3

Step 4

In the Additional DN Attributes field, enter an attribute.

Or

Click

Select

to display the Additional DN Attributes dialog box.

a.

b.

c.

In the Additional DN Attributes dialog box, choose an attribute from the drop-down list.

Enter a value for the attribute.

Click Add. The attribute appears in the list.

d.

Click OK to return to the CSR Parameters dialog box.

The value you added appears in the Additional DN Attributes field in the CSR Parameters dialog box.

Click

OK

.

Saving the Identity Certificate Request

After successfully generating the identity certificate request for one of the Unified Communications proxies, the Identity Certificate Request dialog box appears and prompts you to save the request.

Step 1

Step 2

In the Save CSR to File field, enter the CSR file name and path; for example, c:\asa-csr.txt.

Click

OK

. An information dialog box appears indicating the CSR was saved successfully.

OL-20339-01


42-19


Step 3

Click

OK

to close the dialog and return to the wizard.


Submit the CSR to the certificate authority (CA), for example, by pasting the CSR text into the CSR enrollment page on the CA website.

When the CA returns the signed identity certificate, rerun the Unified Communications Wizard. From the client-side or remote-side certificate management step of the wizard, click

Install ASA’s Identity

Certificate

. See

Installing the ASA Identity Certificate on the Mobility Advantage Server, page 42-20

and


Engine Servers, page 42-21 for the steps to install the identity certificate.

Installing the ASA Identity Certificate on the Mobility Advantage Server

When configuring certificates for the Cisco Mobility Advantage Proxy, you must install the adaptive security appliance identity certificate on the Cisco Mobility Advantage server.

Typically, a certificate authority returns two certificates: your signed identity certificate and the certificate authority’s certificate (referred to as the root certificate). However, some certificate authorities (for example, VeriSign) might also send you an intermediate certificate.

The root certificate from the certificate authority is used to sign other certificates. The root certificate is used by the adaptive security appliance to authenticate your signed identity certificate received from the certificate authority.

If the certificate authority provided an intermediate certificate, you must enter the certificate text in the

Intermediate Certificate (If Applicable) area of the Install ASA’s Identity Certificate dialog box.

For the Cisco Mobility Advantage Proxy, you install the root certificate in another dialog box. See


for the steps to install the root certificate.

Step 1

Step 2

Step 3

In the Intermediate Certificate (If Applicable) area, perform on of the following actions:

•

•




Browse



.



radio button. Copy and paste the PEM format (base64 or hexadecimal) certificate into the area provided.

In the ASA’s Identity Certificate area, perform on of the following actions:

•




Browse



.

•




Click


.

42-20


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Installing the ASA Identity Certificate on the Presence Federation and Cisco

Intercompany Media Engine Servers

When configuring certificates for the Cisco Presence Federation Proxy and Cisco Intercompany Media

Engine Proxy, you must install the adaptive security appliance identity certificate and the root certificate on the Cisco Presence Federation server and Cisco Intercompany Media Engine server, respectively.

Typically, a certificate authority returns two certificates: your signed identity certificate and the certificate authority’s certificate (referred to as the root certificate). The root certificate from the certificate authority is used to sign other certificates. The root certificate is used by the adaptive security appliance to authenticate your signed identity certificate received from the certificate authority.

Step 1

Step 2

Step 3

In the Root CA’s Certificate area, perform on of the following actions:

•




Browse



.

•




In the ASA’s Identity Certificate area, perform on of the following actions:

•

•




Browse



.




Click


.

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42-22


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C H A P T E R

43

Configuring the Cisco Phone Proxy

This chapter describes how to configure the adaptive security appliance for Cisco Phone Proxy feature.


•

•

•

•

•

•

Information About the Cisco Phone Proxy, page 43-1

Licensing Requirements for the Phone Proxy, page 43-4

Prerequisites for the Phone Proxy, page 43-5

Phone Proxy Guidelines and Limitations, page 43-11

Configuring the Phone Proxy, page 43-13

Feature History for the Phone Proxy, page 43-21

Information About the Cisco Phone Proxy

The Cisco Phone Proxy on the adaptive security appliance bridges IP telephony between the corporate

IP telephony network and the Internet in a secure manner by forcing data from remote phones on an untrusted network to be encrypted.

Phone Proxy Functionality

Telecommuters can connect their IP phones to the corporate IP telephony network over the Internet securely via the phone proxy without the need to connect over a VPN tunnel as illustrated by

Figure 43-1 .


43-1 OL-20339-01

Chapter 43 Configuring the Cisco Phone Proxy


Phone Proxy Secure Deployment Figure 43-1

Trusted / Inside / Un-Secured Un-trusted / Outside / Secured

M

M

M

Enterprise

M

M

TCP/RTP

ASA

TLS/SRTP

IP

Internal

IP phone

Internet

Home Router w/NAT

IP

Remote

IP phone

Home Router w/NAT

IP

Remote

IP phone

Unencrypted signaling

Encrypted signaling

The phone proxy supports a Cisco UCM cluster in mixed mode or nonsecure mode. Regardless of the cluster mode, the remote phones that are capable of encryption are always forced to be in encrypted mode. TLS (signaling) and SRTP (media) are always terminated on the adaptive security appliance. The adaptive security appliance can also perform NAT, open pinholes for the media, and apply inspection policies for the SCCP and SIP protocols. In a nonsecure cluster mode or a mixed mode where the phones are configured as nonsecure, the phone proxy behaves in the following ways:

•

•

The TLS connections from the phones are terminated on the adaptive security appliance and a TCP connection is initiated to the Cisco UCM.

SRTP sent from external IP phones to the internal network IP phone via the adaptive security appliance is converted to RTP.

In a mixed mode cluster where the internal IP phones are configured as authenticated, the TLS connection is not converted to TCP to the Cisco UCM but the SRTP is converted to RTP.

In a mixed mode cluster where the internal IP phone is configured as encrypted, the TLS connection remains a TLS connection to the Cisco UCM and the SRTP from the remote phone remains SRTP to the internal IP phone.

Since the main purpose of the phone proxy is to make the phone behave securely while making calls to a nonsecure cluster, the phone proxy performs the following major functions:

•

Creates the certificate trust list (CTL) file, which is used to perform certificate based authentication with remote phones.

•

•

•

•

Modifies the IP phone configuration file when it is requested via TFTP, changes security fields from nonsecure to secure, and signs all files sent to the phone. These modifications secure remote phones by forcing the phones to perform encrypted signaling and media.

Terminates TLS signaling from the phone and initiates TCP or TLS to Cisco UCM

Inserts itself into the media path by modifying the Skinny and SIP signaling messages.

Terminates SRTP and initiates RTP/SRTP to the called party.

43-2


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Note

As an alternative to authenticating remote IP phones through the TLS handshake, you can configure authentication via LSC provisioning. With LSC provisioning you create a password for each remote IP phone user and each user enters the password on the remote IP phones to retrieve the LSC.

Because using LSC provisioning to authenticate remote IP phones requires the IP phones first register in nonsecure mode, Cisco recommends LSC provisioning be done inside the corporate network before giving the IP phones to end-users. Otherwise, having the IP phones register in nonsecure mode requires the Administrator to open the nonsecure signaling port for SIP and SCCP on the adaptive security appliance.

See also the Cisco Unified Communications Manager Security Guide for information on Using the

Certificate Authority Proxy Function (CAPF) to install a locally significant certificate (LSC).

Supported Cisco UCM and IP Phones for the Phone Proxy

Cisco Unified Communications Manager

The following release of the Cisco Unified Communications Manager are supported with the phone proxy:

•

•

•

•

•

•

Cisco Unified CallManager Version 4.

x

Cisco Unified CallManager Version 5.0

Cisco Unified CallManager Version 5.1

Cisco Unified Communications Manager 6.1

Cisco Unified Communications Manager 7.0

Cisco Unified Communications Manager Express 7.0

Cisco Unified IP Phones

The phone proxy supports these IP phone features:

•

•

The Music on Hold (MoH) voice feature

Enterprise features like conference calls on remote phones connected through the phone proxy

•

XML services

Note

The phone proxy supports only the features described in the list above. All other IP phone features not described by this list are unsupported by the phone proxy.

The phone proxy does not support displaying the lock icon on IP phone screens. IP phones display the lock icon on the phone screen during encrypted calls. Even though the lock icon is not displayed on the screen, the IP phone call is still encrypted because the phone proxy encrypts calls by default.

The following IP phones in the Cisco Unified IP Phones 7900 Series are supported with the phone proxy:

•

•

Cisco Unified IP Phone 7975

•

•




OL-20339-01


43-3

Licensing Requirements for the Phone Proxy

•

•

•

•

•

•

•

•

•

•

•



Cisco Unified IP Phone 7961G-GE

Cisco Unified IP Phone 7960 (SCCP protocol support only)




Cisco Unified IP Phone 7941G-GE

Cisco Unified IP Phone 7940 (SCCP protocol support only)

Cisco Unified Wireless IP Phone 7921

Cisco Unified Wireless IP Phone 7925


Note

To support Cisco Unified Wireless IP Phone 7925, you must also configure MIC or LSC on the

IP phone so that it properly works with the phone proxy.

•

CIPC for softphones ( CIPC versions with Authenticated mode only)

Note

The Cisco IP Communicator is supported with the phone proxy VLAN Traversal in authenticated TLS mode. We do not recommend it for remote access because SRTP/TLS is not supported currently on the Cisco IP Communicator.

Note

The adaptive security appliance supports inspection of traffic from Cisco IP Phones running SCCP protocol version 19 and earlier.

Licensing Requirements for the Phone Proxy

The Cisco Phone Proxy feature supported by the adaptive security appliance require a Unified

Communications Proxy license.

The following table shows the Unified Communications Proxy license details by platform:

Model

ASA 5505

ASA 5510

ASA 5520

ASA 5540



1

.



1

.



1

.



1

.


43-4


OL-20339-01


Prerequisites for the Phone Proxy

Model

ASA 5550

ASA 5580



1

.



1

.


2

1.



Note





Note





Note



2.





This section contains the following topics:

•

Media Termination Instance Prerequisites, page 43-5

•

•

•

•

•

•

•

•

•

•

Certificates from the Cisco UCM, page 43-6

DNS Lookup Prerequisites, page 43-7

Cisco Unified Communications Manager Prerequisites, page 43-7

Access List Rules, page 43-7

NAT and PAT Prerequisites, page 43-8

Prerequisites for IP Phones on Multiple Interfaces, page 43-8

7960 and 7940 IP Phones Support, page 43-9

Cisco IP Communicator Prerequisites, page 43-9

Prerequisites for Rate Limiting TFTP Requests, page 43-10

End-User Phone Provisioning, page 43-10

Media Termination Instance Prerequisites

The adaptive security appliance must have a media termination instance that meets the following criteria:

OL-20339-01


43-5



•

•

•

•

•

•

•

•

•

You must configure one media termination for each phone proxy on the adaptive security appliance.

Multiple media termination instances on the adaptive security appliance are not supported.

For the media termination instance, you can configure a global media-termination address for all interfaces or configure a media-termination address for different interfaces. However, you cannot use a global media-termination address and media-termination addresses configured for each interface at the same time.

If you configure a media termination address for multiple interfaces, you must configure an address on each interface that the adaptive security appliance uses when communicating with IP phones.

For example, if you had three interfaces on the adaptive security appliance (one internal interface and two external interfaces) and only one of the external interfaces were used to communicate with

IP phones, you would configure two media termination addresses: one on the internal interface and one on the external interface that communicated with the IP phones.

Only one media-termination address can be configured per interface.

The IP addresses are publicly routable addresses that are unused IP addresses within the address range on that interface.

The IP address on an interface cannot be the same address as that interface on the adaptive security appliance.

The IP addresses cannot overlap with existing static NAT pools or NAT rules.

The IP addresses cannot be the same as the Cisco UCM or TFTP server IP address.

For IP phones behind a router or gateway, you must also meet this prerequisite. On the router or gateway, add routes to the media termination address on the adaptive security appliance interface that the IP phones communicate with so that the phone can reach the media termination address.

Certificates from the Cisco UCM

Import the following certificates which are stored on the Cisco UCM. These certificates are required by the adaptive security appliance for the phone proxy.

•

•

•

•

Cisco_Manufacturing_CA

CAP-RTP-001

CAP-RTP-002

CAPF certificate (Optional)

If LSC provisioning is required or you have LSC enabled IP phones, you must import the CAPF certificate from the Cisco UCM. If the Cisco UCM has more than one CAPF certificate, you must import all of them to the adaptive security appliance.

Note

You can configure LSC provisioning for additional end-user authentication. See the Cisco Unified

Communications Manager configuration guide for information.

For example, the CA Manufacturer certificate is required by the phone proxy to validate the IP phone certificate.

43-6


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DNS Lookup Prerequisites

•

•

•

If you have an fully qualified domain name (FQDN) configured for the Cisco UCM rather than an

IP address, you must configure and enable DNS lookup on the adaptive security appliance.

After configuring the DNS lookup, make sure that the adaptive security appliance can ping the Cisco

UCM with the configured FQDN.

You must configure DNS lookup when you have a CAPF service enabled and the Cisco UCM is not running on the Publisher but the Publisher is configured with a FQDN instead of an IP address.

Cisco Unified Communications Manager Prerequisites

•

•

•

The TFTP server must reside on the same interface as the Cisco UCM.

The Cisco UCM can be on a private network on the inside but you need to have a static mapping for the Cisco UCM on the adaptive security appliance to a public routable address.

If NAT is required for Cisco UCM, it must be configured on the adaptive security appliance, not on the existing firewall.

Access List Rules

If the phone proxy is deployed behind an existing firewall, access-list rules to permit signaling, TFTP requests, and media traffic to the phone proxy must be configured.

If NAT is configured for the TFTP server or Cisco UCMs, the translated “global” address must be used in the access lists.

Table 43-1

lists the ports that are required to be configured on the existing firewall:

Table 43-1 Port Configuration Requirements

Address

Media Termination

TFTP Server

Cisco UCM

Cisco UCM

Port

1024-65535

69

2443

5061

CAPF Service (on Cisco

UCM)

3804

Protocol

UDP

UDP

TCP

TCP

TCP

Description

Allow incoming SRTP

Allow incoming TFTP

Allow incoming secure

SCCP

Allow incoming secure

SIP

Allow CAPF service for

LSC provisioning

Note

All these ports are configurable on the Cisco UCM, except for TFTP. These are the default values and should be modified if they are modified on the Cisco UCM. For example, 3804 is the default port for the CAPF Service. This default value should be modified if it is modified on the

Cisco UCM.

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43-7



NAT and PAT Prerequisites

NAT Prerequisites

•

If NAT is configured for the TFTP server, the NAT configuration must be configured prior to configuring the TFTP Server for the phone proxy.

•

If NAT is configured for the TFTP server or Cisco UCMs, the translated “global” address must be used in the access lists.

PAT Prerequisites

•

When the Skinny inspection global port is configured to use a non-default port, then you must configure the nonsecure port as the global_sccp_port+443

.

Therefore, if

global_sccp_port

is 7000, then the global secure SCCP port is 7443. Reconfiguring the port might be necessary when the phone proxy deployment has more than one Cisco UCM and they must share the interface IP address or a global IP address.

Note

Both PAT configurations—for the nonsecure and secure ports—must be configured.

•

When the IP phones must contact the CAPF on the Cisco UCM and the Cisco UCM is configured with static PAT (LCS provisioning is required), you must configure static PAT for the default CAPF port 3804.

Prerequisites for IP Phones on Multiple Interfaces

When IP phones reside on multiple interfaces, the phone proxy configuration must have the correct IP address set for the Cisco UCM in the CTL file.

See the following example topology for information about how to correctly set the IP address: phones --- (dmz)-----|

|----- ASA PP --- (outside Internet) --- phones phones --- (inside)--|

In this example topology, the following IP address are set:

•

Cisco UCM on the inside interface is set to 10.0.0.5

•

•

The DMZ network is 192.168.1.0/24

The inside network is 10.0.0.0/24

The Cisco UCM is mapped with different global IP addresses from DMZ > outside and inside interfaces

> outside interface.

In the CTL file, the Cisco UCM must have two entries because of the two different IP addresses. For example, if the static statements for the Cisco UCM are as follows: static (inside,outside) 128.106.254.2 10.0.0.5

static (inside,dmz) 192.168.1.2 10.0.0.5

There must be two CTL file record entries for the Cisco UCM: record-entry cucm trustpoint cucm_in_to_out address 128.106.254.2

record-entry cucm trustpoint cucm_in_to_dmz address 192.168.1.2

43-8


OL-20339-01



7960 and 7940 IP Phones Support

•

An LSC must be installed on these IP phones because they do not come pre installed with a MIC.

Install the LSC on each phone before using them with the phone proxy to avoid opening the nonsecure SCCP port for the IP phones to register in nonsecure mode with the Cisco UCM.

See the following document for the steps to install an LSC on IP phones: http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/security/7_0_1/secugd/secucapf.html#w p1093518

Note

If an IP phone already has an LSC installed on it from a different Cisco UCM cluster, delete the

LSC from the different cluster and install an LSC from the current Cisco UCM cluster.

Note

You can configure LSC provisioning for additional end-user authentication. See the Cisco

Unified Communications Manager configuration guide for information.

•

•

•

•

The CAPF certificate must be imported onto the adaptive security appliance.

The CTL file created on the adaptive security appliance must be created with a CAPF record-entry.

The phone must be configured to use only the SCCP protocol because the SIP protocol does not support encryption on these IP phones.

If LSC provisioning is done via the phone proxy, you must add an ACL to allow the IP phones to register with the Cisco UCM on the nonsecure port 2000.

Cisco IP Communicator Prerequisites

To configure Cisco IP Communicator (CIPC) with the phone proxy, you must meet the following prerequisites:

•

Go to Configuration > Firewall > Unified Communications > Phone Proxy and select the “Enable

CICP security mode authentication” check box under the Call Manager and Phone Settings area.

•

•

Create an ACL to allow CIPC to register with the Cisco UCM in nonsecure mode.

Configure null-sha1 as one of the SSL encryption ciphers.

Current versions of Cisco IP Communicator (CIPC) support authenticated mode and perform TLS signaling but not voice encryption.

Because CIPC requires an LSC to perform the TLS handshake, CIPC needs to register with the Cisco

UCM in nonsecure mode using cleartext signaling. To allow the CIPC to register, create an ACL that allows the CIPC to connect to the Cisco UCM on the nonsecure SIP/SCCP signalling ports (5060/2000).

Note

You can configure LSC provisioning for additional end-user authentication. See the Cisco Unified

Communications Manager configuration guide for information.

CIPC uses a different cipher when doing the TLS handshake and requires the null-sha1 cipher and SSL encryption be configured. To add the null-shal cipher, use the show run all ssl command to see the output for the ssl encryption command and add null-shal to the end of the SSL encryption list.

OL-20339-01


43-9



Note

When used with CIPC, the phone proxy does not support end-users resetting their device name in CIPC

(Preferences > Network tab > Use this Device Name field) or Administrators resetting the device name in Cisco Unified CM Administration console (Device menu > Phone Configuration > Device Name field). To function with the phone proxy, the CIPC configuration file must be in the format:

SEP<mac_address>.cnf.xml. If the device name does not follow this format (SEP<mac_address>), CIPC cannot retrieve its configuration file from Cisco UMC via the phone proxy and CIPC will not function.

Prerequisites for Rate Limiting TFTP Requests

In a remote access scenario, we recommend that you configure rate limiting of TFTP requests because any IP phone connecting through the Internet is allowed to send TFTP requests to the TFTP server.

To configure rate limiting of TFTP requests, configure the

police

command in the Modular Policy

Framework. See the


for information about using the

police

command.

Policing is a way of ensuring that no traffic exceeds the maximum rate (in bits/second) that you configure, thus ensuring that no one traffic flow can take over the entire resource. When traffic exceeds the maximum rate, the adaptive security appliance drops the excess traffic. Policing also sets the largest single burst of traffic allowed.

Rate Limiting Configuration Example

The following example describes how you configure rate limiting for TFTP requests by using the

police

command and the Modular Policy Framework.

Begin by determining the conformance rate that is required for the phone proxy. To determine the conformance rate, use the following formula:

X * Y * 8

Where

X = requests per second

Y = size of each packet, which includes the L2, L3, and L4 plus the payload

Therefore, if a rate of 300 TFTP requests/second is required, then the conformance rate would be calculated as follows:

300 requests/second * 80 bytes * 8 = 192000

To control which hosts can ping the media termination address, create an ICMP rule. Go to Configuration

> Device Management > Management Access > ICMP and click the Add button.

End-User Phone Provisioning

The phone proxy is a transparent proxy with respect to the TFTP and signaling transactions. If NAT is not configured for the Cisco UCM TFTP server, then the IP phones need to be configured with the Cisco

UCM cluster TFTP server address.

If NAT is configured for the Cisco UCM TFTP server, then the Cisco UCM TFTP server global address is configured as the TFTP server address on the IP phones.

43-10


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Phone Proxy Guidelines and Limitations

Ways to Deploy IP Phones to End Users

In both options, deploying a remote IP phone behind a commercial Cable/DSL router with NAT capabilities is supported.

Option 1 (Recommended)

Stage the IP phones at corporate headquarters before sending them to the end users:

•

•

The phones register inside the network. IT ensures there are no issues with the phone configurations, image downloads, and registration.

If Cisco UCM cluster was in mixed mode, the CTL file should be erased before sending the phone to the end user.

Advantages of this option are:

•

Easier to troubleshoot and isolate problems with the network or phone proxy because you know whether the phone is registered and working with the Cisco UCM.

•

Better user experience because the phone does not have to download firmware from over a broadband connection, which can be slow and require the user to wait for a longer time.

Option 2

Send the IP phone to the end user. When using option 2, the user must be provided instructions to change the settings on phones with the appropriate Cisco UCM and TFTP server IP address.

Note

As an alternative to authenticating remote IP phones through the TLS handshake, you can configure authentication via LSC provisioning. With LSC provisioning you create a password for each remote IP phone user and each user enters the password on the remote IP phones to retrieve the LSC.

Because using LSC provisioning to authenticate remote IP phones requires the IP phones first register in nonsecure mode, Cisco recommends LSC provisioning be done inside the corporate network before giving the IP phones to end-users. Otherwise, having the IP phones register in nonsecure mode requires the Administrator to open the nonsecure signaling port for SIP and SCCP on the adaptive security appliance.

See also the Cisco Unified Communications Manager Security Guide for information on Using the

Certificate Authority Proxy Function (CAPF) to install a locally significant certificate (LSC).



•

General Guidelines and Limitations, page 43-11

•

Media Termination Address Guidelines and Limitations, page 43-13

General Guidelines and Limitations

The phone proxy has the following general limitations:

•

Only one phone proxy instance can be configured on the adaptive security appliance by using the

phone-proxy

command. See the


for information about the

phone-proxy

command. See also

Creating the Phone Proxy Instance, page 43-17 .


OL-20339-01 43-11



•

•

•

•

•

•

•

•

•

The phone proxy only supports one Cisco UCM cluster. See

Creating the CTL File, page 43-14

for the steps to configure the Cisco UCM cluster for the phone proxy.

The phone proxy is not supported when the adaptive security appliance is running in transparent mode or multiple context mode.

When a remote IP phone calls an invalid internal or external extension, the phone proxy does not support playing the annunciator message from the Cisco UCM. Instead, the remote IP phone plays a fast busy signal instead of the annunciator message "Your call cannot be completed ..." However, when an internal IP phone dials in invalid extension, the annunciator messages plays "Your call cannot be completed ..."

Packets from phones connecting to the phone proxy over a VPN tunnel are not inspected by the adaptive security appliance inspection engines.

The phone proxy does not support IP phones sending Real-Time Control Protocol (RTCP) packets through the adaptive security appliance. Disable RTCP packets in the Cisco Unified CM

Administration console from the Phone Configuration page. See your Cisco Unified

Communications Manager (CallManager) documentation for information about setting this configuration option.

When used with CIPC, the phone proxy does not support end-users resetting their device name in

CIPC (Preferences > Network tab > Use this Device Name field) or Administrators resetting the device name in Cisco Unified CM Administration console (Device menu > Phone Configuration >

Device Name field). To function with the phone proxy, the CIPC configuration file must be in the format: SEP<mac_address>.cnf.xml. If the device name does not follow this format

(SEP<mac_address>), CIPC cannot retrieve its configuration file from Cisco UMC via the phone proxy and CIPC will not function.

The phone proxy does not support IP phones sending SCCP video messages using Cisco VT

Advantage because SCCP video messages do not support SRTP keys.

For mixed-mode clusters, the phone proxy does not support the Cisco Unified Call Manager using

TFTP to send encrypted configuration files to IP phones through the adaptive security appliance.

Multiple IP phones behind one NAT device must be configured to use the same security mode.

When the phone proxy is configured for a mixed-mode cluster and multiple IP phones are behind one NAT device and registering through the phone proxy, all the SIP and SCCP IP phones must be configured as authenticated or encrypted, or all as non-secure on the Unified Call Manager.

For example, if there are four IP phones behind one NAT device where two IP phones are configured using SIP and two IP phones are configured using SCCP, the following configurations on the Unified

Call Manager are acceptable:

–

Two SIP IP phones: one IP phone in authenticated mode and one in encrypted mode, both in authenticated mode, or both in encrypted mode

Two SCCP IP phones: one IP phone in authenticated mode and one in encrypted mode, both in authenticated mode, or both in encrypted mode

–

Two SIP IP phones: both in non-secure mode

Two SCCP IP phones: one IP phone in authenticated mode and one in encrypted mode, both in authenticated mode, both in encrypted mode

–

Two SIP IP phones: one IP phone in authenticated mode and one in encrypted mode, both in authenticated mode, both in encrypted mode

Two SCCP IP phones: both in non-secure mode

This limitation results from the way the application-redirect rules (rules that convert TLS to TCP) are created for the IP phones.

43-12


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Configuring the Phone Proxy

•

•

•

When the adaptive security appliance is used with Unified Communications Manager Express

(Cisco UCME), Directory Services does not work on remote IP phones that register with Cisco UME through the adaptive security appliance. This limitation occurs because the adaptive security appliance requires HTTPS.

When the adaptive security appliance is used with Unified Communications Manager Express

(Cisco UCME), the phone proxy does not support remote IP phones configured with MTP and G729 codec option for media. G729 is supported; however, this configuration results in one way audio when both IP phones used in the call are remote.

The phone proxy does not support displaying the lock icon on IP phone screens. IP phones display the lock icon on the phone screen during encrypted calls. Even though the lock icon is not displayed on the screen, the IP phone call is still encrypted because the phone proxy encrypts calls by default.

Media Termination Address Guidelines and Limitations

The phone proxy has the following limitations relating to configuring the media-termination address:

•

When configuring the media-termination address, the phone proxy does not support having internal

IP phones (IP phones on the inside network) being on a different network interface from the Cisco

UCM unless the IP phones are forced to use the non-secure Security mode.

When internal IP phones are on a different network interface than the Cisco UCM, the IP phones signalling sessions still go through adaptive security appliance; however, the IP phone traffic does not go through the phone proxy. Therefore, Cisco recommends that you deploy internal IP phones on the same network interface as the Cisco UMC.

If the Cisco UMC and the internal IP phones must be on different network interfaces, you must add routes for the internal IP phones to access the network interface of the media-termination address where Cisco UMC resides.

•

•

When the phone proxy is configured to use a global media-termination address, all IP phones see the same global address, which is a public routable address.

If you decide to configure a media-termination address on interfaces (rather than using a global interface), you must configure a media-termination address on at least two interfaces (the inside and an outside interface) before applying the phone-proxy service policy. Otherwise, you will receive an error message when enabling the Phone Proxy with SIP and Skinny Inspection.

The phone proxy can use only one type of media termination instance at a time; for example, you can configure a global media-termination address for all interfaces or configure a media-termination address for different interfaces. However, you cannot use a global media-termination address and media-termination addresses configured for each interface at the same time.



•

Task Flow for Configuring the Phone Proxy, page 43-14

•

•

Creating the CTL File, page 43-14

Adding or Editing a Record Entry in a CTL File, page 43-15

•

•

•

Creating the Media Termination Instance, page 43-16

Creating the Phone Proxy Instance, page 43-17

Adding or Editing the TFTP Server for a Phone Proxy, page 43-19

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43-13



•

Configuring Linksys Routers with UDP Port Forwarding for the Phone Proxy, page 43-20

Task Flow for Configuring the Phone Proxy

Note

This feature is not supported for the Adaptive Security Appliance version 8.1.2.

Configuring the Phone Proxy requires the following steps:

Step 1: Create the CTL file. See

Creating the CTL File, page 43-14 .

Step 2: Create the TLS Proxy instance to handle the encrypted signaling. See

Adding a TLS Proxy

Instance, page 44-8

.

Step 3: Create the Phone Proxy instance. See the

“Creating the Phone Proxy Instance” section on page 43-17

.

Step 4: Configure the media termination address for the Phone Proxy. See

Creating the Media

Termination Instance, page 43-16

.

Note

Before you enable SIP and Skinny inspection for the Phone Proxy (which is done by applying the Phone

Proxy to a service policy rule), the Phone Proxy must have an MTA instance, TLS Proxy, and CTL file assigned to it before the Phone Proxy can be applied to a service policy. Additionally, once a Phone

Proxy is applied to a service policy rule, the Phone Proxy cannot be changed or removed.

Step 5: Enable the Phone Proxy with SIP and Skinny inspection. See

SIP Inspection, page 38-23

and

Skinny (SCCP) Inspection, page 38-36 .

Creating the CTL File

Create a Certificate Trust List (CTL) file that is required by the Phone Proxy. Specify the certificates needed by creating a new CTL file or by specifying the path of an exiting CTL file to parse from Flash memory.

Create trustpoints and generate certificates for each entity in the network (CUCM, CUCM and TFTP,

TFTP server, CAPF) that the IP phones must trust. The certificates are used in creating the CTL file. You need to create trustpoints for each CUCM (primary and secondary if a secondary CUCM is used) and

TFTP server in the network. The trustpoints need to be in the CTL file for the phones to trust the CUCM.

Create the CTL File that will be presented to the IP phones during the TFTP. The address must be the translated or global address of the TFTP server or CUCM if NAT is configured.

When the file is created, it creates an internal trustpoint used by the Phone Proxy to sign the TFTP files.

The trustpoint is named

_internal_PP_

ctl-instance_filename

.

Note

When a CTL file instance is assigned to the Phone Proxy, you cannot modify it in the CTL File pane and the pane is disabled. To modify a CTL File that is assigned to the Phone Proxy, go to the Phone Proxy pane (Configuration > Firewall > Unified Communications > Phone Proxy), and deselect the Use the

Certificate Trust List File generated by the CTL instance check box.

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Use the Create a Certificate Trust List (CTL) File pane to create a CTL file for the Phone Proxy. This pane creates the CTL file that is presented to the IP phones during the TFTP handshake with the adaptive security appliance. For a detailed overview of the CTL file used by the Phone Proxy, see the

“Creating the CTL File” section on page 43-14

.

The Create a Certificate Trust List (CTL) File pane is used to configure the attributes for generating the

CTL file. The name of the CTL file instance is generated by the ASDM. When the user tries to edit the

CTL file instance configuration, the ASDM automatically generates the

shutdown

CLI command first and the

no shutdown

CLI command as the last command.

This pane is available from the Configuration > Firewall > Unified Communications > CTL File pane.

Step 1

Step 2

Step 3

Step 4

Step 5

Open the Configuration > Firewall > Unified Communications > CTL File pane.

Check the Enable Certificate Trust List File check box to enable the feature.

To specify the CTL file to use for the Phone Proxy, perform one of the following:

•

If there is an existing CTL file available, download the CTL file to Flash memory by using the File

Management Tool in the ASDM Tools menu. Select the Use certificates present in the CTL stored in flash radio button and specify the CTL file name and path in the text box.

Use an existing CTL file to install the trustpoints for each entity in the network (CUCM, CUCM and

TFTP, TFTP server, CAPF) that the IP phones must trust. If you have an existing CTL file that contains the correct IP addresses of the entities (namely, the IP address that the IP phones use for the CUCM or TFTP servers), you can be use it to create a new CTL file. Store a copy of the existing

CTL file to Flash memory and rename it something other than

CTLFile.tlv

•

If there is no existing CTL file available, select Create new CTL file radio button.

Add Record entries for each entity in the network such as CUCM, TFTP, and CUCM-TFTP option by clicking

Add

. The Add Record Entry dialog box opens. See

Adding or Editing a Record Entry in a CTL File, page 43-15 .

Specify the number SAST certificate tokens required. The default is 2. maximum allowed is 5.

Because the Phone Proxy generates the CTL file, it needs to create the System Administrator Security

Token (SAST) key to sign the CTL file itself. This key can be generated on the adaptive security appliance. A SAST is created as a self-signed certificate. Typically, a CTL file contains more than one

SAST. In case a SAST is not recoverable, the other one can be used to sign the file later.

Click

Apply

to save the CTL file configuration settings.

Adding or Editing a Record Entry in a CTL File

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Note


Use the Add/Edit Record Entry dialog box to specify the trustpoints to be used for the creation of the

CTL file.

Add additional record-entry configurations for each entity that is required in the CTL file.

Step 1

Step 2

Open the Configuration > Firewall > Unified Communications > CTL File pane.

Check the Enable Certificate Trust List File check box to enable the feature.


43-15



Step 3

Step 4

Step 5

Step 6

In the Type field, specify the type of trustpoint to create:

•

•

cucm: Specifies the role of this trustpoint to be CCM. Multiple CCM trustpoints can be configured.

cucm-tftp: Specifies the role of this trustpoint to be CCM+TFTP. Multiple CCM+TFTP trustpoints can be configured.

•

•

tftp: Specifies the role of this trustpoint to be TFTP. Multiple TFTP trustpoints can be configured.

capf: Specifies the role of this trustpoint to be CAPF. Only one CAPF trustpoint can be configured.

In the Host field, specify the IP address of the trustpoint. The IP address you specify must be the global address of the TFTP server or CUCM if NAT is configured. The global IP address is the IP address as seen by the IP phones because it will be the IP address used for the CTL record for the trustpoint.

In the Certificate field, specify the Identity Certificate for the record entry in the CTL file. You can create a new Identity Certificate by clicking

Manage

. The Manage Identify Certificates dialog box opens. See the

“Configuring Identity Certificates Authentication” section on page 35-14

.

You can add an Identity Certificate by generating a self-signed certificate, obtaining the certificate through SCEP enrollment, or by importing a certificate in PKCS-12 format. Choose the best option based on the requirements for configuring the CTL file.

(Optional) In the Domain Name field, specify the domain name of the trustpoint used to create the DNS field for the trustpoint. This is appended to the Common Name field of the Subject DN to create the DNS

Name. The domain name should be configured when the FQDN is not configured for the trustpoint. Only one domain-name can be specified.

Note

If you are using domain names for your CUCM and TFTP server, you must configure DNS lookup on the adaptive security appliance. Add an entry for each of the outside interfaces on the adaptive security appliance into your DNS server, if such entries are not already present. Each adaptive security appliance outside IP address should have a DNS entry associated with it for lookups. These DNS entries must also be enabled for Reverse Lookup. Additionally, define your DNS server IP address on the adaptive security appliance; for example: dns name-server 10.2.3.4

(IP address of your DNS server).

Creating the Media Termination Instance

Create the media termination instance that you will use in the phone proxy.

The media termination address you configure must meet the requirements as described in

Media

Termination Instance Prerequisites, page 43-5 .

Note

In versions before 8.2(1), you configured one media-termination address (MTA) on the outside interface of the adaptive security appliance where the remote Cisco IP phones were located. In Version 8.2(1) and later, you can configure a global media-termination address for all interfaces or configure a media-termination address for different interfaces.

As a result of this enhancement, the old configuration has been deprecated. You can continue to use the old configuration if desired. However, if you need to change the configuration at all, only the new configuration method is accepted; you cannot later restore the old configuration. If you need to maintain downgrade compatibility, you should keep the old configuration as is.

Step 1

Step 2

Open the Configuration > Firewall > Unified Communications > Media Termination Address pane.

Check the Enable Media Termination Address check box to enable the feature.


43-16 OL-20339-01



Step 3

Step 4

Step 5

In the Media Termination Address Settings area, specify whether to configure a media-termination address (MTA) per interface or to configure a global MTA. You can configure a global media-termination address for all interfaces or configure a media-termination address for different interfaces.

•

To configure an MTA per interface, click the Configure MTA per Interface radio button and click the

Add

button. In the dialog box that appears, specify the interface name and enter an IP address or hostname.

If you configure a media termination address for multiple interfaces, you must configure an address on each interface that the adaptive security appliance uses when communicating with IP phones. The

IP addresses are publicly routable addresses that are unused IP addresses within the address range on that interface.

•

See Media Termination Instance Prerequisites, page 43-5 for the complete list of requirements that

you must follow when creating the media termination instance and configuring the media termination addresses.

To configure a global MTA, click the Configure global MTA on interface radio button and enter the

IP address in the text box. See Media Termination Instance Prerequisites, page 43-5

for the complete list of requirements that you must follow when configuring a global media termination address.

Specify the minimum and maximum values for the RTP port range for the media termination instance.

The minimum port and the maximum port can be a value from 1024 to 65535.

Click

Apply

to save the media termination address configuration settings.

Creating the Phone Proxy Instance

Create the phone proxy instance. To have a fully functional phone proxy, you must also complete additional tasks, such as creating the MTA and enabling SIP and SCCP (Skinny) inspection. See

Task

Flow for Configuring the Phone Proxy, page 43-14

for the complete list of tasks.

Prerequisites

You must have already created the CTL file and TLS proxy instance for the phone proxy.

See

Creating the CTL File, page 43-14 and

Adding a TLS Proxy Instance, page 44-8 .

Note


Use the Configure Phone Proxy pane to add a Phone Proxy.

This pane is available from the Configuration > Firewall > Unified Communications > Phone Proxy pane.

Step 1

Step 2

Step 3

Open the Configuration > Firewall > Unified Communications > Phone Proxy pane.

Check the Enable Phone Proxy check box to enable the feature.

Check the Apply MTA instance to Phone Proxy check box to add the media termination address to the

Phone Proxy instance. You must have a media termination address instance configured. The configured address is added to the Phone Proxy instance.

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Step 4

Note

To configure the media termination address, click the Configure MTA button. The Media

Termination Address dialog box appears. Once you click the Add MTA instance to Phone Proxy check box, the media termination address instance cannot be modified and the button changes to

View MTA Configuration. To change the media termination address, uncheck the Add MTA instance to Phone Proxy check box.

If necessary, add a TFTP server for the Phone Proxy. To add a new TFTP server for the Phone Proxy, click

Add

. The Add TFTP Server dialog box opens. See

Adding or Editing the TFTP Server for a Phone

Proxy, page 43-19 .

Note

The TFTP server must reside on the same interface as the Cisco Unified Call Manager. Additionally, If

NAT is configured for the TFTP server, the NAT configuration must be configured prior to configuring the specifying the TFTP server while creating the Phone Proxy instance.

Step 5

Step 6

Step 7

Step 8

Specify the CTL File to use for the Phone Proxy by doing one of the following:

•

•

To use an existing CTL File, check the Use the Certificate Trust List File generated by the CTL instance check box.

To create a new CTL file for the Phone Proxy, click the link Generate Certificate Trust List File. The

Create a Certificate Trust List (CTL) File pane opens. See

“Creating the CTL File” section on page 43-14

.

To specify the security mode of the CUCM cluster, click one of the following options in the CUCM

Cluster Mode field:

•

Non-secure—Specifies the cluster mode to be in nonsecure mode when configuring the Phone Proxy feature.

•

Mixed—Specifies the cluster mode to be in mixed mode when configuring the Phone Proxy feature.

To configure the idle timeout after which the secure-phone entry is removed from the Phone Proxy database (the default is 5 minutes), enter a value in the format

hh

:

mm

:

ss

.

Since secure phones always request a CTL file upon bootup, the Phone Proxy creates a database that marks the phone as secure. The entries in the secure phone database are removed after a specified configured timeout. The entry timestamp is updated for each registration refresh the Phone Proxy receives for SIP phones and KeepAlives for SCCP phones.

Specify a value that is greater than the maximum timeout value for SCCP KeepAlives and SIP Register refresh. For example, if the SCCP KeepAlives are configured for 1 minute intervals and the SIP Register

Refresh is configured for 3 minutes, configure this timeout value greater than 3 minutes.

To preserve Call Manager configuration on the IP phones, check the Preserve the Call Manager’s configuration on the phone... check box. When this check box is uncheck, the following service settings are disabled on the IP phones:

•

PC Port

•

•

•

•

Gratuitous ARP

Voice VLAN access

Web Access

Span to PC Port

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Step 9

Step 10

Step 11

To force Cisco IP Communicator (CIPC) softphones to operate in authenticated mode when CIPC softphones are deployed in a voice and data VLAN scenario, check the Enable CIPC security mode authentication check box.

Because CIPC requires an LSC to perform the TLS handshake, CIPC needs to register with the CUCM in nonsecure mode using cleartext signaling. To allow the CIPC to register, create an ACL that allows the CIPC to connect to the CUCM on the nonsecure SIP/SCCP signalling ports (5060/2000).

CIPC uses a different cipher when doing the TLS handshake and requires the null-sha1 cipher and SSL encryption be configured. To add the null-shal cipher, go to Configuration > Device Management >

Advanced > SSL Settings > Encryption section. Select the null-shal SSL encryption type and add it to the Available Algorithms.

Current versions of Cisco IP Communicator (CIPC) support authenticated mode and perform TLS signaling but not voice encryption.

To configure an HTTP proxy for the Phone Proxy feature that is written into the IP phone's configuration file under the <proxyServerURL> tag, do the following:

a.

b.

Check the Configure a http-proxy which would be written into the phone’s config file... check box.

In the IP Address field, type the IP address of the HTTP proxy and the listening port of the HTTP proxy.

c.

The IP address you enter should be the global IP address based on where the IP phone and HTTP proxy server is located. You can enter a hostname in the IP Address field when that hostname can be resolved to an IP address by the adaptive security appliance (for example, DNS lookup is configured) because the adaptive security appliance will resolve the hostname to an IP address. If a port is not specified, the default will be 8080.

In the Interface field, select the interface on which the HTTP proxy resides on the adaptive security appliance.

Setting the proxy server configuration option for the Phone Proxy allows for an HTTP proxy on the DMZ or external network in which all the IP phone URLs are directed to the proxy server for services on the phones. This setting accommodates nonsecure HTTP traffic, which is not allowed back into the corporate network.

Click

Apply

to save the Phone Proxy configuration settings.

Note

After creating the Phone Proxy instance, you enable it with SIP and Skinny inspection. See

SIP

Inspection, page 38-23 and

Skinny (SCCP) Inspection, page 38-36

.

However, before you enable SIP and Skinny inspection for the Phone Proxy (which is done by applying the Phone Proxy to a service policy rule), the Phone Proxy must have an MTA instance, TLS Proxy, and

CTL file assigned to it before the Phone Proxy can be applied to a service policy. Additionally, once a

Phone Proxy is applied to a service policy rule, the Phone Proxy cannot be changed or removed.

Adding or Editing the TFTP Server for a Phone Proxy

Note


OL-20339-01


43-19



Step 1

Step 2

Step 3

Open the Configuration > Firewall > Unified Communications > Phone Proxy pane.

Check the Enable Phone Proxy check box to enable the feature.

To add or edit the TFTP Server information for the phone proxy, click the

Add

or

Edit

button. The

Add/Edit TFTP Server dialog box appears.

Use the Add/Edit TFTP Server dialog box to specify the IP address of the TFTP server and the interface on which the TFTP server resides.

The Phone Proxy must have at least one CUCM TFTP server configured. Up to five TFTP servers can be configured for the Phone Proxy.

The TFTP server is assumed to be behind the firewall on the trusted network; therefore, the Phone Proxy intercepts the requests between the IP phones and TFTP server.

Note

If NAT is configured for the TFTP server, the NAT configuration must be configured prior to specifying the TFTP server while creating the Phone Proxy instance.

Step 4

Step 5

Step 6

Step 7

In the TFTP Server IP Address field, specify the address of the TFTP server. Create the TFTP server using the actual internal IP address.

(Optional) In the Port field, specify the port the TFTP server is listening in on for the TFTP requests.

This should be configured if it is not the default TFTP port 69.

In the Interface field, specify the interface on which the TFTP server resides. The TFTP server must reside on the same interface as the Cisco Unified Call Manager (CUCM).

Click OK to apply the settings.

Configuring Linksys Routers with UDP Port Forwarding for the Phone Proxy

When IP phones are behind a NAT-capable router, the router can be configured to forward the UDP ports to the IP address of the IP phone. Specifically, configure the router for UDP port forwarding when an IP phone is failing during TFTP requests and the failure is due to the router dropping incoming TFTP data packets. Configure the router to enable UDP port forwarding on port 69 to the IP phone.

As an alternative of explicit UDP forwarding, some Cable/DSL routers require you to designate the IP phone as a DMZ host. For Cable/DSL routers, this host is a special host that receives all incoming connections from the public network.

When configuring the phone proxy, there is no functional difference between an IP phone that has UDP ports explicitly forwarded or an IP phone designated as a DMZ host. The choice is entirely dependent upon the capabilities and preference of the end user.

Configuring Your Router

Your firewall/router needs to be configured to forward a range of UDP ports to the IP phone. This will allow the IP phone to receive audio when you make/receive calls.

Note

Different Cable/DSL routers have different procedures for this configuration. Furthermore most

NAT-capable routers will only allow a given port range to be forwarded to a single IP address

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Feature History for the Phone Proxy

The configuration of each brand/model of firewall/router is different, but the task is the same. For specific instructions for your brand and model of router, please contact the manufacturer’s website.

Linksys Routers

Step 1

Step 2

Step 3

From your web browser, connect to the router administrative web page. For Linksys, this is typically something like http://192.168.1.1

.

Click Applications & Gaming or the Port Forwarding tab (whichever is present on your router).

Locate the table containing the port forwarding data and add an entry containing the following values:

Table 43-2

Application

IP phone

TFTP

Port Forwarding Values to Add to Router

Start

1024

69

End

65535

69

Protocol

UDP

UDP

IP Address

Phone IP address

Phone IP address

Enabled

Checked

Checked

Step 4

Click Save Settings. Port forwarding is configured.


Table 43-3


Table 43-3 Feature History for Cisco Phone Proxy

Feature Name

Cisco Phone Proxy

NAT for the media termination address

Releases

8.0(4)

8.1(2)


The phone proxy feature was introduced. The Phone Proxy feature was accessible in ASDM by choosing the following options:

Configuration > Firewall > Advanced > Encrypted Traffic

Inspection > Phone Proxy pane

The Media Termination fields were removed from the

Phone Proxy pane and added to the Media Termination pane:

Configuration > Firewall > Advanced > Encrypted Traffic

Inspection > Media Termination Address pane

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C H A P T E R

44

Configuring the T

LS Proxy for Encrypted Voice

Inspection

This chapter describes how to configure the adaptive security appliance for the TLS Proxy for Encrypted

Voice Inspection feature.


•

Information about the TLS Proxy for Encrypted Voice Inspection, page 44-1

•

•

•

•

Licensing for the TLS Proxy, page 44-3

Prerequisites for the TLS Proxy for Encrypted Voice Inspection, page 44-4

Configuring the TLS Proxy for Encrypted Voice Inspection, page 44-5

Feature History for the TLS Proxy for Encrypted Voice Inspection, page 44-17

Information about the TLS Proxy for Encrypted Voice Inspection

End-to-end encryption often leaves network security appliances “blind” to media and signaling traffic, which can compromise access control and threat prevention security functions. This lack of visibility can result in a lack of interoperability between the firewall functions and the encrypted voice, leaving businesses unable to satisfy both of their key security requirements.

The adaptive security appliance is able to intercept and decrypt encrypted signaling from Cisco encrypted endpoints to the Cisco Unified Communications Manager (Cisco UCM), and apply the required threat protection and access control. It can also ensure confidentiality by re-encrypting the traffic onto the Cisco UCM servers.

Typically, the adaptive security appliance TLS Proxy functionality is deployed in campus unified communications network. This solution is ideal for deployments that utilize end to end encryption and firewalls to protect Unified Communications Manager servers.

The security appliance in

Figure 44-1 serves as a proxy for both client and server, with Cisco IP Phone

and Cisco UCM interaction.


44-1 OL-20339-01

Chapter 44 Configuring the TLS Proxy for Encrypted Voice Inspection

Information about the TLS Proxy for Encrypted Voice Inspection

Figure 44-1 TLS Proxy Flow

Cisco IP Phone

IP

Client Hello

Cisco ASA

(Proxy) Server Hello

(Proxy) Server Certificate

(Proxy) Server Key Exchange

Certificate Request

(Proxy) Server Hello Done

Client Certificate

Client Key Exchange

Certificate Verify

[Change Cipher Spec]

Finished


Finished

(Proxy) Client Hello

Cisco CallManager

M

Server Hello

Server Certificate

Server Key Exchange

Certificate Request

Server Hello Done

(Proxy) Dynamic Client Certificate

(Proxy) Client Key Exchange

Certificate Verify


Finished

Application Data INSPECTION


Finished

Application Data

Decryption and Inspection of Unified Communications Encrypted Signaling

With encrypted voice inspection, the security appliance decrypts, inspects and modifies (as needed, for example, performing NAT fixup), and re-encrypts voice signaling traffic while all of the existing VoIP inspection functions for Skinny and SIP protocols are preserved. Once voice signaling is decrypted, the plaintext signaling message is passed to the existing inspection engines.

The security appliance acts as a TLS proxy between the Cisco IP Phone and Cisco UCM. The proxy is transparent for the voice calls between the phone and theCisco UCM. Cisco IP Phones download a

Certificate Trust List from the Cisco UCM before registration which contains identities (certificates) of the devices that the phone should trust, such as TFTP servers and Cisco UCM servers. To support server

44-2


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Licensing for the TLS Proxy

proxy, the CTL file must contain the certificate that the security appliance creates for the Cisco UCMs.

To proxy calls on behalf of the Cisco IP Phone, the security appliance presents a certificate that the Cisco

UCM can verify, which is a Local Dynamic Certificate for the phone, issued by the certificate authority on the security appliance.

TLS proxy is supported by the Cisco Unified CallManager Release 5.1 and later. You should be familiar with the security features of the Cisco UCM. For background and detailed description of Cisco UCM security, see the Cisco Unified CallManager document: http://www.cisco.com/univercd/cc/td/doc/product/voice/c_callmg/5_0/sec_vir/ae/sec504/index.htm

TLS proxy applies to the encryption layer and must be configured with an application layer protocol inspection. You should be familiar with the inspection features on the adaptive security appliance, especially Skinny and SIP inspection.

Model

ASA 5505

ASA 5510

ASA 5520

ASA 5540

ASA 5550

ASA 5580

Licensing for the TLS Proxy

The TLS proxy for encrypted voice inspection feature supported by the adaptive security appliance require a Unified Communications Proxy license.




1

.



1

.



1

.



1

.



1

.



1

.


2

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44-3


Prerequisites for the TLS Proxy for Encrypted Voice Inspection

1.



Note





Note





Note



2.


Table 44-1 shows the default and maximum TLS session details by platform.

Table 44-1 Default and Maximum TLS Sessions on the Security Appliance

Security Appliance Platform

ASA 5505

ASA 5510

ASA 5520

ASA 5540

ASA 5550

ASA 5580

Default TLS Sessions

10

100

300

1000

2000

4000

Maximum TLS Sessions

80

200

1200

4500

4500

13,000



Prerequisites for the TLS Proxy for Encrypted Voice Inspection

Before configuring TLS proxy, the following prerequisites are required:

•

•

You must set clock on the security appliance before configuring TLS proxy. To set the clock manually and display clock, use the

clock set

and

show clock

commands. We recommend that the security appliance use the same NTP server as the Cisco Unified CallManager cluster. TLS handshake may fail due to certificate validation failure if clock is out of sync between the security appliance and the Cisco Unified CallManager server.

3DES-AES license is needed to interoperate with the Cisco Unified CallManager. AES is the default cipher used by the Cisco Unified CallManager and Cisco IP Phone.

•

Import the following certificates which are stored on the Cisco UCM. These certificates are required by the adaptive security appliance for the phone proxy.

–

Cisco_Manufacturing_CA

–

CAP-RTP-001

44-4


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–

–

CAP-RTP-002

CAPF certificate (Optional)

If LSC provisioning is required or you have LSC enabled IP phones, you must import the CAPF certificate from the Cisco UCM. If the Cisco UCM has more than one CAPF certificate, you must import all of them to the adaptive security appliance.

See Chapter 43, “Configuring the Cisco Phone Proxy.” For example, the CA Manufacturer certificate

is required by the phone proxy to validate the IP phone certificate.



•

Configure TLS Proxy Pane, page 44-7

•

•

•

•

•

•

Adding a TLS Proxy Instance, page 44-8

Add TLS Proxy Instance Wizard – Server Configuration, page 44-9

Add TLS Proxy Instance Wizard – Client Configuration, page 44-10

Add TLS Proxy Instance Wizard – Other Steps, page 44-12

Edit TLS Proxy Instance – Server Configuration, page 44-12

Edit TLS Proxy Instance – Client Configuration, page 44-13

CTL Provider

Use the CTL Provider option to configure Certificate Trust List provider service.

The CTL Provider pane lets you define and configure Certificate Trust List provider service to enable inspection of encrypted traffic.

Fields

•

CTL Provider Name—Lists the CTL Provider name.

•

Client Details—Lists the name and IP address of the client.

•

•

•

•

–

–

Interface Name—Lists the defined interface name.

IP Address—Lists the defined interface IP address.

Certificate Name—Lists the certificate to be exported.

Add—Adds a CTL Provider.

Edit—Edits a CTL Provider.

Delete—Deletes a CTL Provider.

Modes


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44-5


CTL Provider

Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

Add/Edit CTL Provider

The Add/Edit CTL Provider dialog box lets you define the parameters for the CTL Provider.

Fields

•

CTL Provider Name—Specifies the CTL Provider name.

•

Certificate to be Exported—Specifies the certificate to be exported to the client.

–

Certificate Name—Specifies the name of the certificate to be exported to the client.

•

–

Manage—Manages identity certificates.

Client Details—Specifies the clients allowed to connect.

–

Client to be Added—Specifies the client interface and IP address to add to the client list.

Interface—Specifies client interface.

•

IP Address—Specifies the client IP address.

Add—Adds the new client to the client list.

Delete—Deletes the selected client from the client list.

More Options—Specifies the available and active algorithms to be announced or matched during the

TLS handshake.

–

–

Parse the CTL file provided by the CTL Client and install trustpoints—Trustpoints installed by this option have names prefixed with “_internal_CTL_.” If disabled, each Call Manager server and CAPF certificate must be manually imported and installed.

Port Number—Specifies the port to which the CTL provider listens. The port must be the same as the one listened to by the CallManager servers in the cluster (as configured under Enterprise

Parameters on the CallManager administration page). The default is 2444.

–

Authentication—Specifies the username and password that the client authenticates with the provider.

Username—Client username.

Password—Client password.

Confirm Password—Client password.

Modes


44-6


OL-20339-01


Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

CTL Provider

Configure TLS Proxy Pane

OL-20339-01

Note


You can configure the TLS Proxy from the Configuration > Firewall > Unified Communications > TLS

Proxy pane.

Configuring a TLS Proxy lets you use the TLS Proxy to enable inspection of SSL encrypted VoIP signaling, namely Skinny and SIP, interacting with Cisco Call Manager and enable the adaptive security appliance for the Cisco Unified Communications features:

•

TLS Proxy for the Cisco Unified Presence Server (CUPS), part of Presence Federation

•

•

TLS Proxy for the Cisco Unified Mobility Advantage (CUMA) server, part of Mobile Advantage

Phone Proxy

Fields

•

TLS Proxy Name—Lists the TLS Proxy name.

•

•

Server Proxy Certificate—Lists the trustpoint, which is either self-signed or enrolled with a certificate server.

Local Dynamic Certificate Issuer—Lists the local certificate authority to issue client or server dynamic certificates.

•

•

•

•

•

Client Proxy Certificate—Lists the proxy certificate for the TLS client. The adaptive security appliance uses the client proxy certificate to authenticate the TLS client during the handshake between the proxy and the TLS client. The certificate can be either self-signed, enrolled with a certificate authority, or issued by the third party.

Add—Adds a TLS Proxy by launching the Add TLS Proxy Instance Wizard. See

Adding a TLS

Proxy Instance, page 44-8

for the steps to create a TLS Proxy instance.

Edit—Edits a TLS Proxy. The fields in the Edit panel area identical to the fields displayed when you add a TLS Proxy instance. See

Edit TLS Proxy Instance – Server Configuration, page 44-12 and

Edit

TLS Proxy Instance – Client Configuration, page 44-13 .

Delete—Deletes a TLS Proxy.

Maximum Sessions—Lets you specify the maximum number of TLS Proxy sessions to support.

–

Specify the maximum number of TLS Proxy sessions that the ASA needs to support.

–

Maximum number of sessions—The minimum is 1. The maximum is dependent on the platform:

Cisco ASA 5505 security appliance: 10



44-7

CTL Provider






Note

The maximum number of sessions is global to all TLS proxy sessions.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Adding a TLS Proxy Instance

Note


Use the Add TLS Proxy Instance Wizard to add a TLS Proxy to enable inspection of SSL encrypted VoIP signaling, namely Skinny and SIP, interacting with Cisco Call Manager and to support the Cisco Unified

Communications features on the adaptive security appliance.

This wizard is available from the Configuration > Firewall > Unified Communications > TLS Proxy pane.

Step 1

Step 2

Step 3

Step 4

Open the Configuration > Firewall > Unified Communications > TLS Proxy pane.

To add a new TLS Proxy Instance, click

Add

.

The Add TLS Proxy Instance Wizard opens.

In the TLS Proxy Name field, type the TLS Proxy name.

Click

Next

.

The Add TLS Proxy Instance Wizard – Server Configuration dialog box opens. In this step of the wizard, configure the server proxy parameters for original TLS Server—the Cisco Unified Call Manager

(CUCM) server, the Cisco Unified Presence Server (CUPS), or the Cisco Unified Mobility Advantage

(CUMA) server. See the

“Add TLS Proxy Instance Wizard – Server Configuration” section on page 44-9

.

After configuring the server proxy parameters, the wizard guides you through configuring client proxy parameters (see

“Add TLS Proxy Instance Wizard – Client Configuration” section on page 44-10

) and provides instructions on the steps to complete outside the ASDM to make the TLS Proxy fully functional

(see the

“Add TLS Proxy Instance Wizard – Other Steps” section on page 44-12

).

44-8


OL-20339-01


Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add TLS Proxy Instance Wizard – Server Configuration

CTL Provider

Note




The Add TLS Proxy Instance Wizard is available from the Configuration > Firewall > Unified

Communications > TLS Proxy pane.

Step 1

Step 2

Step 3

Complete the first step of the Add TLS Proxy Instance Wizard. See “Adding a TLS Proxy Instance” section on page 44-8 .

The Add TLS Proxy Instance Wizard – Server Configuration dialog box opens.

Specify the server proxy certificate by doing one of the following:

•

To add a new certificate, click

Manage

. The Manage Identify Certificates dialog box opens.

When the Phone Proxy is operating in a mixed-mode CUCM cluster, you must import the CUCM certificate by clicking

Add

in the Manage Identify Certificates dialog box. See

“Configuring

Identity Certificates Authentication” section on page 35-14

.

•

To select an existing certificate, select one from the drop-down list.

When you are configuring the TLS Proxy for the Phone Proxy, select the certificate that has a filename beginning with

_internal_PP_

. When you create the CTL file for the Phone Proxy, the adaptive security appliance, creates an internal trustpoint used by the Phone Proxy to sign the TFTP files. The trustpoint is named

_internal_PP_


.

The server proxy certificate is used to specify the trustpoint to present during the TLS handshake. The trustpoint can be self-signed or enrolled locally with the certificate service on the proxy. For example, for the Phone Proxy, the server proxy certificate is used by the Phone Proxy during the handshake with the IP phones.

To install the TLS server certificate in the adaptive security appliance trust store, so that the adaptive security appliance can authenticate the TLS server during TLS handshake between the proxy and the

TLS server, click

Install TLS Server’s Certificate

.

The Manage CA Certificates dialog box opens. See the


. Click

Add

to open the Install Certificate dialog box. See the “Adding or Installing a CA

Certificate” section on page 35-9 .

OL-20339-01


44-9


CTL Provider

Step 4

Step 5

When you are configuring the TLS Proxy for the Phone Proxy, click


and install the Cisco Unified Call Manager (CUCM) certificate so that the proxy can authenticate the IP phones on behalf of the CUCM server.

To require the adaptive security appliance to present a certificate and authenticate the TLS client during

TLS handshake, check the Enable client authentication during TLS Proxy handshake check box.

When adding a TLS Proxy Instance for Mobile Advantage (the CUMC client and CUMA server), disable the check box when the client is incapable of sending a client certificate.

Click

Next

.

The Add TLS Proxy Instance Wizard – Client Configuration dialog box opens. In this step of the wizard, configure the client proxy parameters for original TLS Client—the CUMC client for Mobile Advantage,

CUP or MS LCS/OCS client for Presence Federation, or the IP phone for the Phone Proxy. See the

“Add

TLS Proxy Instance Wizard – Client Configuration” section on page 44-10

.

After configuring the client proxy parameters, the wizard provides instructions on the steps to complete outside the ASDM to make the TLS Proxy fully functional (see the

“Add TLS Proxy Instance Wizard –

Other Steps” section on page 44-12

).

Add TLS Proxy Instance Wizard – Client Configuration

Note




This wizard is available from the Configuration > Firewall > Unified Communications > TLS Proxy pane.

Step 1

Step 2

Complete the first two steps of the Add TLS Proxy Instance Wizard. See the “Adding a TLS Proxy

Instance” section on page 44-8 and

“Add TLS Proxy Instance Wizard – Client Configuration” section on page 44-10

.

The Add TLS Proxy Instance Wizard – Client Configuration dialog box opens.

To specify a client proxy certificate to use for the TLS Proxy, perform the following. Select this option when the client proxy certificate is being used between two servers; for example, when configuring the

TLS Proxy for Presence Federation, which uses the Cisco Unified Presence Server (CUPS), both the TLS client and TLS server are both servers.

a.

b.

Check the Specify the proxy certificate for the TLS Client... check box.

Select a certificate from the drop-down list.

Or

To create a new client proxy certificate, click

Manage



.

44-10


OL-20339-01


CTL Provider

Note

When you are configuring the TLS Proxy for the Phone Proxy and it is using the mixed security mode for the CUCM cluster, you must configure the LDC Issuer. The LDC Issuer lists the local certificate authority to issue client or server dynamic certificates.

Step 3

To specify an LDC Issuer to use for the TLS Proxy, perform the following. When you select and configure the LDC Issuer option, the adaptive security appliance acts as the certificate authority and issues certificates to TLS clients.

a.

Click the Specify the internal Certificate Authority to sign the local dynamic certificate for phones... check box.

b.

Click the Certificates radio button and select a self-signed certificate from the drop-down list or click

Manage

to create a new LDC Issuer. The Manage Identify Certificates dialog box opens. See the


Or

Click the Certificate Authority radio button to specify a Certificate Authority (CA) server. When you specify a CA server, it needs to be created and enabled in the adaptive security appliance. To create and enable the CA server, click

Manage

. The Edit CA Server Settings dialog box opens. See the

“Authenticating Using the Local CA” section on page 35-22

.

Note

To make configuration changes after the local certificate authority has been configured for the first time, disable the local certificate authority.

Step 4

Step 5 c.

In the Key-Pair Name field, select a key pair from the drop-list. The list contains the already defined

RSA key pair used by client dynamic certificates. To see the key pair details, including generation time, usage, modulus size, and key data, click

Show

.

Or

To create a new key pair, click

New

. The Add Key Pair dialog box opens. See the

“Configuring


for details about the Key Pair fields.

In the Security Algorithms area, specify the available and active algorithms to be announced or matched during the TLS handshake.

•

Available Algorithms—Lists the available algorithms to be announced or matched during the TLS handshake: des-sha1, 3des-sha1, aes128-sha1, aes256-sha1, and null-sha1.

Add—Adds the selected algorithm to the active list.

Remove—Removes the selected algorithm from the active list.

•

Active Algorithms—Lists the active algorithms to be announced or matched during the TLS handshake: des-sha1, 3des-sha1, aes128-sha1, aes256-sha1, and null-sha1. For client proxy (acting as a TLS client to the server), the user-defined algorithms replace the original ones from the hello message for asymmetric encryption method between the two TLS legs. For example, the leg between the proxy and Call Manager may be NULL cipher to offload the Call Manager.

Move Up—Moves an algorithm up in the list.

Move Down—Moves an algorithm down in the list.

Click

Next

.

OL-20339-01


44-11

CTL Provider


The Add TLS Proxy Instance Wizard – Other Steps dialog box opens. The Other Steps dialog box provides instructions on the steps to complete outside the ASDM to make the TLS Proxy fully functional

(see

“Add TLS Proxy Instance Wizard – Other Steps” section on page 44-12 ).

Add TLS Proxy Instance Wizard – Other Steps

Note


The last dialog box of the Add TLS Proxy Instance Wizard specifies the additional steps required to make TLS Proxy fully functional. In particular, you need to perform the following tasks to complete the

TLS Proxy configuration:

•

Export the local CA certificate or LDC Issuer and install them on the original TLS server.

To export the LDC Issuer, go to Configuration > Firewall > Advanced > Certificate Management >

Identity Certificates > Export. See the

“Exporting an Identity Certificate” section on page 35-17

.

•

•

•

For the TLS Proxy, enable Skinny and SIP inspection between the TLS server and TLS clients. See the

“SIP Inspection” section on page 38-23

and the

“Skinny (SCCP) Inspection” section on page 38-36

. When you are configuring the TLS Proxy for Presence Federation (which uses CUP), you only enable SIP inspection because the feature supports only the SIP protocol.

For the TLS Proxy for CUMA, enable MMP inspection.

When using the internal Certificate Authority of the adaptive security appliance to sign the LDC

Issuer for TLS clients, perform the following:

–

Use the Cisco CTL Client to add the server proxy certificate to the CTL file and install the CTL file on the adaptive security appliance.

–

For information on the Cisco CTL Client, see “Configuring the Cisco CTL Client” in

Cisco

Unified CallManager Security Guide

.

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/security/5_0_4/secuauth.html

To install the CTL file on the adaptive security appliance, go to Configuration > Firewall >

Unified Communications > CTL Provider > Add. The Add CTL Provider dialog box opens. For information on using this dialog box to install the CTL file, see the

“Add/Edit CTL Provider” section on page 44-6 .

Create a CTL provider instance for connections from the CTL clients. See the

“Add/Edit CTL

Provider” section on page 44-6 .

Edit TLS Proxy Instance – Server Configuration

Note


The TLS Proxy enables inspection of SSL encrypted VoIP signaling, namely Skinny and SIP, interacting with Cisco Call Manager and to support the Cisco Unified Communications features on the adaptive security appliance.

44-12


OL-20339-01


CTL Provider

Use the Edit TLS Proxy – Server Configuration tab to edit the server proxy parameters for the original

TLS Server—the Cisco Unified Call Manager (CUCM) server, the Cisco Unified Presence Server

(CUPS), or the Cisco Unified Mobility Advantage (CUMA) server.

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7


To edit a TLS Proxy Instance, click

Edit

.

The Edit TLS Proxy Instance dialog box opens.

If necessary, click the

Server Configuration

tab.

Specify the server proxy certificate by doing one of the following:

•

To add a new certificate, click

Manage

. The Manage Identify Certificates dialog box opens.

When the Phone Proxy is operating in a mixed-mode CUCM cluster, you must import the CUCM certificate by clicking

Add

in the Manage Identify Certificates dialog box. See the

“Configuring CA

Certificate Authentication” section on page 35-9

.

•

To select an existing certificate, select one from the drop-down list.

When you are configuring the TLS Proxy for the Phone Proxy, select the certificate that has a filename beginning with

_internal_PP_

. When you create the CTL file for the Phone Proxy, the adaptive security appliance, creates an internal trustpoint used by the Phone Proxy to sign the TFTP files. The trustpoint is named

_internal_PP_


.

The server proxy certificate is used to specify the trustpoint to present during the TLS handshake. The trustpoint can be self-signed or enrolled locally with the certificate service on the proxy. For example, for the Phone Proxy, the server proxy certificate is used by the Phone Proxy during the handshake with the IP phones.

To install the TLS server certificate in the adaptive security appliance trust store, so that the adaptive security appliance can authenticate the TLS server during TLS handshake between the proxy and the

TLS server, click


.

The Manage CA Certificates dialog box opens. See the


. Click

Add

to open the Install Certificate dialog box. See the “Configuring CA Certificate

Authentication” section on page 35-9 .

When you are configuring the TLS Proxy for the Phone Proxy, click


and install the Cisco Unified Call Manager (CUCM) certificate so that the proxy can authenticate the IP phones on behalf of the CUCM server.

To require the adaptive security appliance to present a certificate and authenticate the TLS client during

TLS handshake, check the Enable client authentication during TLS Proxy handshake check box.

When adding a TLS Proxy Instance for Mobile Advantage (the CUMC client and CUMA server), disable the check box when the client is incapable of sending a client certificate.

Click

Apply


Edit TLS Proxy Instance – Client Configuration

Note


OL-20339-01


44-13


CTL Provider

The TLS Proxy enables inspection of SSL encrypted VoIP signaling, namely Skinny and SIP, interacting with Cisco Call Manager and to support the Cisco Unified Communications features on the adaptive security appliance.

The fields in the Edit TLS Proxy dialog box are identical to the fields displayed when you add a TLS

Proxy instance. Use the Edit TLS Proxy – Client Configuration tab to edit the client proxy parameters for the original TLS Client, such as IP phones, CUMA clients, the Cisco Unified Presence Server

(CUPS), or the Microsoft OCS server.

Step 1

Step 2

Step 3

Step 4


To edit a TLS Proxy Instance, click

Edit

.

The Edit TLS Proxy Instance dialog box opens.

If necessary, click the

Client Configuration

tab.

To specify a client proxy certificate to use for the TLS Proxy, perform the following. Select this option when the client proxy certificate is being used between two servers; for example, when configuring the

TLS Proxy for Presence Federation, which uses the Cisco Unified Presence Server (CUPS), both the TLS client and TLS server are both servers.

a.

Check the Specify the proxy certificate for the TLS Client... check box.

b.

Select a certificate from the drop-down list.

Or

To create a new client proxy certificate, click

Manage



.

Note

When you are configuring the TLS Proxy for the Phone Proxy and it is using the mixed security mode for the CUCM cluster, you must configure the LDC Issuer. The LDC Issuer lists the local certificate authority to issue client or server dynamic certificates.

Step 5

To specify an LDC Issuer to use for the TLS Proxy, perform the following. When you select and configure the LDC Issuer option, the adaptive security appliance acts as the certificate authority and issues certificates to TLS clients.

a.

Click the Specify the internal Certificate Authority to sign the local dynamic certificate for phones... check box.

b.

Click the Certificates radio button and select a self-signed certificate from the drop-down list or click

Manage

to create a new LDC Issuer. The Manage Identify Certificates dialog box opens. See the


.

Or

Click the Certificate Authority radio button to specify a Certificate Authority (CA) server. When you specify a CA server, it needs to be created and enabled in the adaptive security appliance. To create and enable the CA server, click

Manage

. The Edit CA Server Settings dialog box opens. See the

“Authenticating Using the Local CA” section on page 35-22 .

Note

To make configuration changes after the local certificate authority has been configured for the first time, disable the local certificate authority.

44-14


OL-20339-01


TLS Proxy

Step 6

Step 7 c.

In the Key-Pair Name field, select a key pair from the drop-list. The list contains the already defined

RSA key pair used by client dynamic certificates. To see the key pair details, including generation time, usage, modulus size, and key data, click

Show

.

Or

To create a new key pair, click

New

. The Add Key Pair dialog box opens. See the

“Configuring


for details about the Key Pair fields.

In the Security Algorithms area, specify the available and active algorithms to be announced or matched during the TLS handshake.

•

Available Algorithms—Lists the available algorithms to be announced or matched during the TLS handshake: des-sha1, 3des-sha1, aes128-sha1, aes256-sha1, and null-sha1.



•

Active Algorithms—Lists the active algorithms to be announced or matched during the TLS handshake: des-sha1, 3des-sha1, aes128-sha1, aes256-sha1, and null-sha1. For client proxy (acting as a TLS client to the server), the user-defined algorithms replace the original ones from the hello message for asymmetric encryption method between the two TLS legs. For example, the leg between the proxy and Call Manager may be NULL cipher to offload the Call Manager.



Click

Apply


TLS Proxy

This feature is supported only for ASA versions 8.0.x prior to 8.0.4 and for version 8.1.

Note

This feature is not supported for the Adaptive Security Appliance versions prior to 8.0.4 and for version

8.1.2.

Use the TLS Proxy option to enable inspection of SSL encrypted VoIP signaling, namely Skinny and

SIP, interacting with Cisco CallManager.

The TLS Proxy pane lets you define and configure Transaction Layer Security Proxy to enable inspection of encrypted traffic.

Fields

•

TLS Proxy Name—Lists the TLS Proxy name.

•

Server—Lists the trustpoint, which is either self-signed or enrolled with a certificate server.

•

•

•

•


Local Dynamic Certificate Key Pair—Lists the RSA key pair used by client or server dynamic certificates.

Add—Adds a TLS Proxy.

Edit—Edits a TLS Proxy.


OL-20339-01 44-15

TLS Proxy


•

•

Delete—Deletes a TLS Proxy.

Maximum Sessions—Lets you specify the maximum number of TLS Proxy sessions to support.

–

Specify the maximum number of TLS Proxy sessions that the ASA needs to support. By default,

ASA supports 300 sessions.—Enables maximum number of sessions option.

–

Maximum number of sessions:—The minimum is 1. The maximum is dependent on the platform. The default is 300.

Modes


Firewall Mode

Routed


Multiple


• • • •

Add/Edit TLS Proxy

System

—

Note

This feature is not supported for the Adaptive Security Appliance versions prior to 8.0.4 and for version

8.1.2.

The Add/Edit TLS Proxy dialog box lets you define the parameters for the TLS Proxy.

Fields

•

TLS Proxy Name—Specifies the TLS Proxy name.

•

Server Configuration—Specifies the proxy certificate name.

–

Server—Specifies the trustpoint to be presented during the TLS handshake. The trustpoint could be self-signed or enrolled locally with the certificate service on the proxy.

•

Client Configuration—Specifies the local dynamic certificate issuer and key pair.

–


Certificate Authority Server—Specifies the certificate authority server.

Certificate—Specifies a certificate.

•

–

Manage—Configures the local certificate authority. To make configuration changes after it has been configured for the first time, disable the local certificate authority.

Local Dynamic Certificate Key Pair—Lists the RSA key pair used by client dynamic certificates.

Key-Pair Name—Specifies a defined key pair.

Show—Shows the key pair details, including generation time, usage, modulus size, and key data.

New—Lets you define a new key pair.

More Options—Specifies the available and active algorithms to be announced or matched during the

TLS handshake.

44-16


OL-20339-01


Feature History for the TLS Proxy for Encrypted Voice Inspection

–

–

Available Algorithms—Lists the available algorithms to be announced or matched during the

TLS handshake: des-sha1, 3des-sha1, aes128-sha1, aes256-sha1, and null-sha1.



Active Algorithms—Lists the active algorithms to be announced or matched during the TLS handshake: des-sha1, 3des-sha1, aes128-sha1, aes256-sha1, and null-sha1. For client proxy

(acting as a TLS client to the server), the user-defined algorithms replace the original ones from the hello message for asymmetric encryption method between the two TLS legs. For example, the leg between the proxy and CallManager may be NULL cipher to offload the CallManager.




Table 44-2



Feature Name

TLS Proxy

Releases

8.0(2)


The TLS proxy feature was introduced.

OL-20339-01


44-17



44-18


OL-20339-01

C H A P T E R

45



Communications Mobility Advantage Proxy features.


•

•

•

•

Information about the Cisco Mobility Advantage Proxy Feature, page 45-1

Licensing for the Cisco Mobility Advantage Proxy Feature, page 45-6

Configuring Cisco Mobility Advantage, page 45-6

Feature History for Cisco Mobility Advantage, page 45-7

Information about the Cisco Mobility Advantage Proxy Feature


•

•

•

Cisco Mobility Advantage Proxy Functionality, page 45-1

Mobility Advantage Proxy Deployment Scenarios, page 45-2

Trust Relationships for Cisco UMA Deployments, page 45-5

Cisco Mobility Advantage Proxy Functionality

To support Cisco UMA for the Cisco Mobility Advantage solution, the mobility advantage proxy

(implemented as a TLS proxy) includes the following functionality:

•

•

The ability to allow no client authentication during the handshake with clients.

Allowing an imported PKCS-12 certificate to server as a proxy certificate.

The adaptive security appliance includes an inspection engine to validate the Cisco UMA Mobile

Multiplexing Protocol (MMP).

MMP is a data transport protocol for transmitting data entities between Cisco UMA clients and servers.

As shown in

Figure 45-1 , MMP must be run on top of a connection-oriented protocol (the underlying

transport) and is intended to be run on top of a secure transport protocol such as TLS. The Orative

Markup Language (OML) protocol is intended to be run on top of MMP for the purposes of data synchronization, as well as the HTTP protocol for uploading and downloading large files.


45-1 OL-20339-01

Chapter 45 Configuring Cisco Mobility Advantage


Figure 45-1

OML

MMP Stack

HTTP

MMP

TLS/SSL

TCP

I P etc.

The TCP/TLS default port is 5443. There are no embedded NAT or secondary connections.

Cisco UMA client and server communications can be proxied via TLS, which decrypts the data, passes it to the inspect MMP module, and re-encrypt the data before forwarding it to the endpoint. The inspect

MMP module verifies the integrity of the MMP headers and passes the OML/HTTP to an appropriate handler. The adaptive security appliance takes the following actions on the MMP headers and data:

•

•

•

Verifies that client MMP headers are well-formed. Upon detection of a malformed header, the TCP session is terminated.

Verifies that client to server MMP header lengths are not exceeded. If an MMP header length is exceeded (4096), then the TCP session is terminated.

Verifies that client to server MMP content lengths are not exceeded. If an entity content length is exceeded (4096), the TCP session is terminated.

Note

4096 is the value currently used in MMP implementations.

Because MMP headers and entities can be split across packets, the adaptive security appliance buffers data to ensure consistent inspection. The SAPI (stream API) handles data buffering for pending inspection opportunities. MMP header text is treated as case insensitive and a space is present between header text and values. Reclaiming of MMP state is performed by monitoring the state of the TCP connection.

Mobility Advantage Proxy Deployment Scenarios

Figure 45-2

and

Figure 45-3

show the two deployment scenarios for the TLS proxy used by the Cisco

Mobility Advantage solution. In scenario 1 (the recommended deployment architecture), the adaptive security appliance functions as both the firewall and TLS proxy. In scenario 2, the adaptive security appliance functions as the TLS proxy only and works with an existing firewall. In both scenarios, the clients connect from the Internet.

In the scenario 1 deployment, the adaptive security appliance is between a Cisco UMA client and a Cisco

UMA server. The Cisco UMA client is an executable that is downloaded to each smartphone. The Cisco

UMA client applications establishes a data connection, which is a TLS connection, to the corporate

Cisco UMA server. The adaptive security appliance intercepts the connections and inspects the data that the client sends to the Cisco UMA server.

45-2


OL-20339-01


Figure 45-2


The TLS proxy for the Cisco Mobility Advantage solution does not support client authentication because the Cisco UMA client cannot present a certificate.

Security

Appliance as Firewall with Mobility Advantage Proxy and MMP Inspection

Enterprise Services

Mobile Data

Network (GPRS

Data Channel)

MMP/SSL/TLS

Cisco UMC Client

PSTN

Hostname: cuma.example.com

Network: 192.0.2.0/24

IP Address: 192.0.2.140

Port: 5443

Voice Channel

ASA with

TLS Proxy

Network:

10.1.1.0/24

IP Address:

10.1.1.2

Port: 5443

Active Directory

Exchange

MMP/SSL/TLS

Cisco Unified

Presence

Network:

10.1.1.0/24

IP Address:

10.1.1.1

Cisco UMA

Server

MP

Voice mail

M

Cisco UCM

Conference

In Figure 45-2 , the adaptive security appliance performs static NAT by translating the Cisco UMA server

10.1.1.2 IP address to 192.0.2.140.

Figure 45-3 shows deployment scenario 2, where the adaptive security appliance functions as the TLS

proxy only and does not function as the corporate firewall. In this scenario, the adaptive security appliance and the corporate firewall are performing NAT. The corporate firewall will not be able to predict which client from the Internet needs to connect to the corporate Cisco UMA server. Therefore, to support this deployment, you can take the following actions:

•

Set up a NAT rule for inbound traffic that translates the destination IP address 192.0.2.41 to

172.16.27.41.

•

Set up an interface PAT rule for inbound traffic translating the source IP address of every packet so that the corporate firewall does not need to open up a wildcard pinhole. The Cisco UMA server receives packets with the source IP address 192.0.12.183.

See Chapter 27, “Configuring Network Object NAT”

and

Chapter 28, “Configuring Twice NAT”

for information.

Note

This interface PAT rule converges the Cisco UMA client IP addresses on the outside interface of the adaptive security appliance into a single IP address on the inside interface by using different source ports. Performing this action is often referred as “outside PAT”. “Outside PAT” is not recommended when TLS proxy for Cisco Mobility Advantage is enabled on the same interface of the adaptive security appliance with phone proxy, Cisco Unified Presence, or any other features involving application inspection. “Outside PAT” is not supported completely by application inspection when embedded address translation is needed.

OL-20339-01


45-3



Figure 45-3 Cisco UMC/Cisco UMA Architecture – Scenario 2: Security Appliance as Mobility

Advantage Proxy Only

Client connects to cuma.example.com

(192.0.2.41)

Cisco UMC Client

Internet

ISP

Gateway

Corporate

Firewall

DMZ Internal Network

IP Address:

172.16.27.41

(DMZ routable) eth0

192.0.2.41/24 outside

192.0.2.182/24

ASA with inside

TLS Proxy

Cisco UMA

M

Cisco UCM

Active

Directory

Exchange

Enterprise Network

Cisco Unified

Presence

Voice mail

MP

Conference

Mobility Advantage Proxy Using NAT/PAT

In both scenarios (

Figure 45-2 and

Figure 45-3 ), NAT can be used to hide the private address of the Cisco

UMA servers.

In scenario 2 ( Figure 45-3

), PAT can be used to converge all client traffic into one source IP, so that the firewall does not have to open up a wildcard pinhole for inbound traffic.

45-4


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Trust Relationships for Cisco UMA Deployments

To establish a trust relationship between the Cisco UMC client and the adaptive security appliance, the adaptive security appliance uses the Cisco UMA server certificate and keypair or the adaptive security appliance obtains a certificate with the Cisco UMA server FQDN (certificate impersonation). Between the adaptive security appliance and the Cisco UMA server, the adaptive security appliance and Cisco

UMA server use self-signed certificates or certificates issued by a local certificate authority.

Figure 45-4 shows how you can import the Cisco UMA server certificate onto the adaptive security

appliance. When the Cisco UMA server has already enrolled with a third-party CA, you can import the certificate with the private key onto the adaptive security appliance. Then, the adaptive security appliance has the full credentials of the Cisco UMA server. When a Cisco UMA client connects to the

Cisco UMA server, the adaptive security appliance intercepts the handshake and uses the Cisco UMA server certificate to perform the handshake with the client. The adaptive security appliance also performs a handshake with the server.

Figure 45-4 How the Security Appliance Represents Cisco UMA – Private Key Sharing

3rd Party CA

Certificate

Authority

Enroll with FQDN of Cisco UMA

Certificate

ASA

Cisco UMA

Internet

Cisco UMC Client

TLS (Cisco UMA Certificate)

Key 1

Inspected and

Modified

(if needed)

Certificate with

Private Key

TLS (Self-signed, or from local CA)

Key 2

Figure 45-5 shows another way to establish the trust relationship. Figure 45-5

shows a green field deployment, because each component of the deployment has been newly installed. The adaptive security appliance enrolls with the third-party CA by using the Cisco UMA server FQDN as if the adaptive security appliance is the Cisco UMA server. When the Cisco UMA client connects to the adaptive security appliance, the adaptive security appliance presents the certificate that has the Cisco UMA server

FQDN. The Cisco UMA client believes it is communicating to with the Cisco UMA server.

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45-5


Licensing for the Cisco Mobility Advantage Proxy Feature

Figure 45-5 How the Security Appliance Represents Cisco UMA – Certificate Impersonation

3rd Party CA

Certificate

Authority

Enroll with FQDN of Cisco UMA

Certificate

ASA

Cisco UMA

Internet

Cisco UMC Client

TLS (ASA Certificate with Cisco UMA FQDN)

Key 1

Inspected and

Modified

(if needed)


Key 2

A trusted relationship between the adaptive security appliance and the Cisco UMA server can be established with self-signed certificates. The adaptive security appliance's identity certificate is exported, and then uploaded on the Cisco UMA server truststore. The Cisco UMA server certificate is downloaded, and then uploaded on the adaptive security appliance truststore by creating a trustpoint and using the

crypto ca authenticate

command.

Licensing for the Cisco Mobility Advantage Proxy Feature

The Cisco Unified Communications proxy features (Cisco Phone Proxy, TLS proxy for encrypted voice inspection, and the Cisco Presence Federation Proxy) supported by the adaptive security appliance require a Unified Communications Proxy license. However, in Version 8.2(2) and later, the Mobility

Advantage proxy no longer requires a Unified Communications Proxy license.

The following table shows the licensing requirements for the Mobility Advantage proxy:

Model

All models


Base License.




This section includes the following topic:

•

Task Flow for Configuring Cisco Mobility Advantage, page 45-7

45-6


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Feature History for Cisco Mobility Advantage

Task Flow for Configuring Cisco Mobility Advantage

To configure for the adaptive security appliance to perform TLS proxy and MMP inspection as shown in

Figure 45-2

and

Figure 45-3

, perform the following tasks.

It is assumed that self-signed certificates are used between the adaptive security appliance and the Cisco

UMA server.

To configure the Cisco Mobility Advantage Proxy by using ASDM, choose Wizards > Unified

Communications Wizard from the menu. The Unified Communications Wizard opens. From the first page, select the Cisco Mobility Advantage Proxy option under the Remote Access section.

The wizard automatically creates the necessary TLS proxy, then guides you through creating the Unified

Presence Proxy instance, importing and installing the required certificates, and finally enables the MMP inspection for the Mobility Advantage traffic automatically.

The wizard guides you through four steps to create the Mobility Advantage Proxy:

Step 1

Step 2

Step 3

Step 4

Select the Mobility Advantage Proxy option.

Specify setting to define the proxy topology, such the IP address of the Mobility Advantage server.

Configure the server-side certificate management, namely the certificates that are exchanged between the local Mobility Advantage server and the adaptive security appliance.

Configure the client-side certificate management, namely the certificates that are exchanged between the

Unified Mobile Communicator and the adaptive security appliance


Proxy. See

Chapter 42, “Using the Cisco Unified Communication Wizard”



Table 45-1



Feature Name

Cisco Mobility Advantage Proxy

Releases

8.0(4)

Cisco Mobility Advantage Proxy 8.3(1)


The Cisco Mobility Advantage Proxy feature was introduced.

The Unified Communications Wizard was added to ASDM.

By using the wizard, you can configure the Cisco Mobility

Advantage Proxy.

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45-7



45-8


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C H A P T E R

46

Configuring Cisco Unified Presence

This chapter describes how to configure the adaptive security appliance for Cisco Unified Presence.


•

•

•

•

Information About Cisco Unified Presence, page 46-1

Licensing for Cisco Unified Presence, page 46-7

Configuring Cisco Unified Presence Proxy for SIP Federation, page 46-7

Feature History for Cisco Unified Presence, page 46-8

Information About Cisco Unified Presence


•

•

•

•

•

Architecture for Cisco Unified Presence for SIP Federation Deployments, page 46-1

Trust Relationship in the Presence Federation, page 46-3

Security Certificate Exchange Between Cisco UP and the Security Appliance, page 46-4

XMPP Federation Deployments, page 46-5

Configuration Requirements for XMPP Federation, page 46-5

Architecture for Cisco Unified Presence for SIP Federation Deployments

Figure 46-1 depicts a Cisco Unified Presence/LCS Federation scenario with the adaptive security

appliance as the presence federation proxy (implemented as a TLS proxy). The two entities with a TLS connection are the “Routing Proxy” (a dedicated Cisco UP) in Enterprise X and the Microsoft Access

Proxy in Enterprise Y. However, the deployment is not limited to this scenario. Any Cisco UP or Cisco

UP cluster could be deployed on the left side of the adaptive security appliance; the remote entity could be any server (an LCS, an OCS, or another Cisco UP).

The following architecture is generic for two servers using SIP (or other adaptive security appliance inspected protocols) with a TLS connection.

Entity X: Cisco UP/Routing Proxy in Enterprise X

Entity Y: Microsoft Access Proxy/Edge server for LCS/OCS in Enterprise Y


46-1 OL-20339-01

Chapter 46 Configuring Cisco Unified Presence


Figure 46-1

Cisco UCM

Cisco UP

(UK)

Typical Cisco Unified Presence/LCS Federation Scenario

Enterprise X

DMZ

Enterprise Y

DMZ private network

Cisco UCM private

Cisco UP

(HK)

AD

Cisco UCM

Cisco UP

(US)

10.0.0.2

Routing

Proxy

(Cisco UP)

Inside

192.0.2.1

ASA

8.0.4

Outside

SIP

Internet

192.0.2.254

Access

Proxy

LCS

Director

LCS

UC

(Ann)

Orative

(Ann)

IPPM

(Ann)

Functions as:

• TLS Proxy

• NAT w/SIP

rewrite

• Firewall

MOC

(Yao)

MOC

(Zak)

In the above architecture, the adaptive security appliance functions as a firewall, NAT, and TLS proxy, which is the recommended architecture. However, the adaptive security appliance can also function as

NAT and the TLS proxy alone, working with an existing firewall.

Either server can initiate the TLS handshake (unlike IP Telephony or Cisco Unified Mobility, where only the clients initiate the TLS handshake). There are by-directional TLS proxy rules and configuration.

Each enterprise can have an adaptive security appliance as the TLS proxy.

In

Figure 46-1

, NAT or PAT can be used to hide the private address of Entity X. In this situation, static

NAT or PAT must be configured for foreign server (Entity Y) initiated connections or the TLS handshake

(inbound). Typically, the public port should be 5061. The following static PAT command is required for the Cisco UP that accepts inbound connections: hostname(config)#

static (inside,outside) tcp 192.0.2.1 5061 10.0.0.2 5061 netmask

255.255.255.255

The following static PAT must be configured for each Cisco UP that could initiate a connection (by sending SIP SUBSCRIBE) to the foreign server.

For Cisco UP with the address 10.0.0.2, enter the following command: hostname(config)#


255.255.255.255

hostname(config)#

static (inside,outside) udp 192.0.2.1 5070 10.0.0.2 5070 netmask

255.255.255.255

hostname(config)#


255.255.255.255

For another Cisco UP with the address 10.0.0.3, you must use a different set of PAT ports, such as 45062 or 45070: hostname(config)#


255.255.255.255

46-2


OL-20339-01



hostname(config)#


255.255.255.255

hostname(config)#

static (inside,outside) udp 192.0.2.1 45070 10.0.0.3 5070 netmask

255.255.255.255

hostname(config)#


255.255.255.255

hostname(config)#


255.255.255.255

Dynamic NAT or PAT can be used for the rest of the outbound connections or the TLS handshake. The adaptive security appliance SIP inspection engine takes care of the necessary translation (fixup).

hostname(config)#

global (outside) 102 192.0.2.1 netmask 255.255.255.255

hostname(config)#

nat (inside) 102 0.0.0.0 0.0.0.0

Figure 46-2 illustrates an abstracted scenario with Entity X connected to Entity Y through the presence

federation proxy on the adaptive security appliance. The proxy is in the same administrative domain as

Entity X. Entity Y could have another adaptive security appliance as the proxy but this is omitted for simplicity.

Figure 46-2 Abstracted Presence Federation Proxy Scenario between Two Server Entities

Enterprise X Enterprise Y

Entity X

I nside ASA

TLS Pro x y

Outside

10.0.0.2

10.0.0.1

192.0.2.1

192.0.2.2

S I P/TLS

I nternet

192.0.2.254

Entity Y

Enterprise Y Firewall omitted

For the Entity X domain name to be resolved correctly when the adaptive security appliance holds its credential, the adaptive security appliance could be configured to perform NAT for Entity X, and the domain name is resolved as the Entity X public address for which the adaptive security appliance provides proxy service.

For further information about configuring Cisco Unified Presence Federation for SIP Federation, see the

Integration Guide for Configuring Cisco Unified Presence for Interdomain Federation.: http://www.cisco.com/en/US/products/ps6837/products_installation_and_configuration_guides_list.ht

ml

Trust Relationship in the Presence Federation

Within an enterprise, setting up a trust relationship is achievable by using self-signed certificates or you can set it up on an internal CA.

Establishing a trust relationship cross enterprises or across administrative domains is key for federation.

Cross enterprises you must use a trusted third-party CA (such as, VeriSign). The adaptive security appliance obtains a certificate with the FQDN of the Cisco UP (certificate impersonation).

OL-20339-01


46-3



For the TLS handshake, the two entities could validate the peer certificate via a certificate chain to trusted third-party certificate authorities. Both entities enroll with the CAs. The adaptive security appliance as the TLS proxy must be trusted by both entities. The adaptive security appliance is always associated with one of the enterprises. Within that enterprise (Enterprise X in

Figure 46-1

), the entity and the adaptive security appliance could authenticate each other via a local CA, or by using self-signed certificates.

To establish a trusted relationship between the adaptive security appliance and the remote entity (Entity

Y), the adaptive security appliance can enroll with the CA on behalf of Entity X (Cisco UP). In the enrollment request, the Entity X identity (domain name) is used.

Figure 46-3

shows the way to establish the trust relationship. The adaptive security appliance enrolls with the third party CA by using the Cisco UP FQDN as if the adaptive security appliance is the Cisco

UP.

Figure 46-3 How the Security Appliance Represents Cisco Unified Presence – Certificate

Impersonate

3rd Party CA

Certificate

Authority

Enroll with FQDN of Cisco UP

Certificate

Cisco UP

ASA

Internet

Microsoft Presence Server

Access

Proxy

LCS/OCS

Director

Certificate with

Private Key


Key 1

Inspected and

Modified

(if needed)

TLS (Cisco UP Certificate)

Key 2

Security Certificate Exchange Between Cisco UP and the Security Appliance

You need to generate the keypair for the certificate (such as cup_proxy_key

) used by the adaptive security appliance, and configure a trustpoint to identify the self-signed certificate sent by the adaptive security appliance to Cisco UP (such as cup_proxy

) in the TLS handshake.

For the adaptive security appliance to trust the Cisco UP certificate, you need to create a trustpoint to identify the certificate from the Cisco UP (such as cert_from_cup

), and specify the enrollment type as terminal to indicate that you will paste the certificate received from the Cisco UP into the terminal.

46-4


OL-20339-01



XMPP Federation Deployments

Figure 46-4 provides an example of an XMPP federated network between Cisco Unified Presence

enterprise deployment and an IBM Sametime enterprise deployment. TLS is optional for XMPP federation. adaptive security appliance acts only as a firewall for XMPP federation; it does not provide

TLS proxy functionality or PAT for XMPP federation.

Figure 46-4 Basic XMPP Federated Network between Cisco Unified Presence and IBM Sametime

Enterprise X Enterprise Z

DMZ private network

CUCM

Inter-cluster communication

CUP

CUP

CUP (UK)

CUCM

CUP

CUP

CUP (US)

private DMZ

*ASA

8.0

Passthrough for

XMPP Requesting

No Termination of connections

Internet

XMPP

IBM

Sametime

Gateway

Directory

XMPP

Client

(Ann)

XMPP

Client

(Tom)

Sametime

(Bob)

Sametime

(Bill)

*Cisco Adaptive Security Appliance

ASA functions as:

• Firewall

• Open Port 5269

There are two DNS servers within the internal Cisco Unified Presence enterprise deployment. One DNS server hosts the Cisco Unified Presence private address. The other DNS server hosts the Cisco Unified

Presence public address and a DNS SRV records for SIP federation (_sipfederationtle), and XMPP federation (_xmpp-server) with Cisco Unified Presence. The DNS server that hosts the Cisco Unified

Presence public address is located in the local DMZ.

For further information about configuring Cisco Unified Presence Federation for XMPP Federation, see the

Integration Guide for Configuring Cisco Unified Presence Release 8.0 for Interdomain Federation

: http://www.cisco.com/en/US/products/ps6837/products_installation_and_configuration_guides_list.ht

ml

Configuration Requirements for XMPP Federation

For XMPP Federation, adaptive security appliance acts as a firewall only. You must open port 5269 for both incoming and outgoing XMPP federated traffic on adaptive security appliance.


OL-20339-01 46-5



These are sample access lists to open port 5269 on adaptive security appliance.

Allow traffic from any address to any address on port 5269: access-list ALLOW-ALL extended permit tcp any any eq 5269

Allow traffic from any address to any single node on port 5269: access-list ALLOW-ALL extended permit tcp any host <private cup IP address> eq 5269

If you do not configure the access list above, and you publish additional XMPP federation nodes in DNS, you must configure access to each of these nodes, for example: object network obj_host_<private cup ip address>

#host <private cup ip address> object network obj_host_<private cup2 ip address>

#host <private cup2 ip address> object network obj_host_<public cup ip address>

#host <public cup ip address>

....

Configure the following NAT commands: nat (inside,outside) source static obj_host_<private cup1 IP> obj_host_<public cup IP> service obj_udp_source_eq_5269 obj_udp_source_eq_5269 nat (inside,outside) source static obj_host_<private cup1 IP> obj_host_<public cup IP> service obj_tcp_source_eq_5269 obj_tcp_source_eq_5269

If you publish a single public IP address in DNS, and use arbitrary ports, configure the following:

(This example is for two additional XMPP federation nodes) nat (inside,outside) source static obj_host_<private cup2 ip> obj_host_<public cup IP> service obj_udp_source_eq_5269 obj_udp_source_eq_25269 nat (inside,outside) source static obj_host_<private cup2 ip> obj_host_<public cup IP> service obj_tcp_source_eq_5269 obj_tcp_source_eq_25269 nat (inside,outside) source static obj_host_<private cup3 ip> obj_host_<public cup IP> service obj_udp_source_eq_5269 obj_udp_source_eq_35269 nat (inside,outside) source static obj_host_<private cup3 ip> obj_host_<public cup IP> service obj_tcp_source_eq_5269 obj_tcp_source_eq_35269

If you publish multiple public IP addresses in DNS all using port 5269, configure the following:

(This example is for two additional XMPP federation nodes) nat (inside,outside) source static obj_host_<private cup2 ip> obj_host_<public cup2 IP> service obj_udp_source_eq_5269 obj_udp_source_eq_5269 nat (inside,outside) source static obj_host_<private cup2 ip> obj_host_<public cup2 IP> service obj_tcp_source_eq_5269 obj_tcp_source_eq_5269 nat (inside,outside) source static obj_host_<private cup3 ip> obj_host_<public cup3 IP> service obj_udp_source_eq_5269 obj_udp_source_eq_5269 nat (inside,outside) source static obj_host_<private cup3 ip> obj_host_<public cup IP> service obj_tcp_source_eq_5269 obj_tcp_source_eq_5269

46-6


OL-20339-01


Licensing for Cisco Unified Presence

Licensing for Cisco Unified Presence

The Cisco Unified Presence feature supported by the adaptive security appliance require a Unified

Communications Proxy license.


Model

ASA 5505

ASA 5510

ASA 5520



1

.



1

.



1

.

ASA 5540

ASA 5550

ASA 5580



1

.



1

.



1

.


2

1.



Note





Note





Note



2.




Configuring Cisco Unified Presence Proxy for SIP Federation

This section contains the following topic:

•

Task Flow for Configuring Cisco Unified Presence Federation Proxy for SIP Federation, page 46-8

OL-20339-01


46-7


Feature History for Cisco Unified Presence

Task Flow for Configuring Cisco Unified Presence Federation Proxy for SIP

Federation

To configure a Cisco Unified Presence/LCS Federation scenario with the adaptive security appliance as the TLS proxy where there is a single Cisco UP that is in the local domain and self-signed certificates are used between the Cisco UP and the adaptive security appliance (like the scenario shown in

Figure 46-1

), perform the following tasks.

To configure the Cisco Unified Presence proxy by using ASDM, choose Wizards > Unified

Communications Wizard from the menu. The Unified Communications Wizard opens. From the first page, select the Cisco Unified Presence Proxy option under the Business-to-Business section.

The wizard automatically creates the necessary TLS proxy, then guides you through creating the Unified

Presence Proxy instance, importing and installing the required certificates, and finally enables the SIP and SCCP inspection for the Presence Federation traffic automatically.

The wizard guides you through four steps to create the Presence Federation Proxy:

Step 1

Step 2

Step 3

Step 4

Select the Presence Federation Proxy option.

Specify setting to define the proxy topology, such the IP address of the Presence Federation server.

Configure the local-side certificate management, namely the certificates that are exchanged between the local Unified Presence Federation server and the adaptive security appliance.

Configure the remote-side certificate management, namely the certificates that are exchanged between the remote server and the adaptive security appliance

The wizard completes by displaying a summary of the configuration created for Presence Federation.

See the Unified Communications Wizard section in this documentation for more information.

Feature History for Cisco Unified Presence



Feature Name



Releases

8.0(4)

8.3(1)


The Cisco Unified Presence proxy feature was introduced.

The Unified Communications Wizard was added to ASDM.

By using the wizard, you can configure the Cisco Presence

Federation Proxy.

Support for XMPP Federation was introduced.

46-8


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C H A P T E R

47

Configuring Cisco Intercompany Media Engine

Proxy

This chapter describes how to configure the adaptive security appliance for Cisco Intercompany Media

Engine Proxy.


•

Information About Cisco Intercompany Media Engine Proxy, page 47-1

•

•

•

•

Licensing for Cisco Intercompany Media Engine, page 47-8


Configuring Cisco Intercompany Media Engine Proxy, page 47-11

Feature History for Cisco Intercompany Media Engine Proxy, page 47-38

Information About Cisco Intercompany Media Engine Proxy


•

•

Features of Cisco Intercompany Media Engine Proxy, page 47-1

How the UC-IME Works with the PSTN and the Internet, page 47-2

•

•

•

Tickets and Passwords, page 47-3

Call Fallback to the PSTN, page 47-5

Architecture and Deployment Scenarios for Cisco Intercompany Media Engine, page 47-5

Features of Cisco Intercompany Media Engine Proxy

Cisco Intercompany Media Engine enables companies to interconnect on-demand, over the Internet with advanced features made available by VoIP technologies. Cisco Intercompany Media Engine allows for business-to-business federation between Cisco Unified Communications Manager clusters in different enterprises by utilizing peer-to-peer, security, and SIP protocols to create dynamic SIP trunks between businesses. A collection of enterprises work together to end up looking like one large business with inter-cluster trunks between them.

The adaptive security appliance applies its existing TLS proxy, SIP Application Layer Gateway (ALG), and SIP verification features to the functioning of Cisco Intercompany Media Engine.

Cisco Intercompany Media Engine has the following key features:


OL-20339-01 47-1

Chapter 47 Configuring Cisco Intercompany Media Engine Proxy


•

•

•

•

•

•

•

•

•

•

•

Works with existing phone numbers: Cisco Intercompany Media Engine works with the phone numbers an enterprise currently has and does not require an enterprise to learn new numbers or change providers to use Cisco Intercompany Media Engine.

Works with existing IP phones: Cisco Intercompany Media Engine works with the existing IP phones within an enterprise. However, the feature set in business-to-business calls is limited to the capabilities of the IP phones.

Does not require purchasing new services: Cisco Intercompany Media Engine does not require any new services from any service providers. Customers continue to use the PSTN connectivity they have and the Internet connectivity they have today. Cisco Intercompany Media Engine gradually moves calls off the PSTN and onto the Internet.

Provides a full Cisco Unified Communications experience: Because Cisco Intercompany Media

Engine creates inter-cluster SIP trunks between enterprises, any Unified Communication features that work over the SIP trunk and only require a SIP trunk work with the Cisco Intercompany Media

Engine, thus providing a Unified Communication experience across enterprises.

Works on the Internet: Cisco Intercompany Media Engine was designed to work on the Internet. It can also work on managed extranets.

Provides worldwide reach: Cisco Intercompany Media Engine can connect to any enterprise anywhere in the world, as long as the enterprise is running Cisco Intercompany Media Engine technology. There are no regional limitations. This is because Cisco Intercompany Media Engine utilizes two networks that both have worldwide reach—the Internet and the PSTN.

Allows for unlimited scale: Cisco Intercompany Media Engine can work with any number of enterprises.

Is self-learning: The system is primarily self-learning. Customers do not have to enter information about other businesses: no phone prefixes, no IP address, no ports, no domain names, nor certificates. Customers need to configure information about their own networks, and provide policy information if they want to limit the scope of Cisco Intercompany Media Engine.

Is secure: Cisco Intercompany Media Engine is secure, utilizing a large number of different technologies to accomplish this security.

Includes anti-spam: Cisco Intercompany Media Engine prevents people from setting up software on the Internet that spams enterprises with phone calls. It provides an extremely high barrier to entry.

Provides for QoS management: Cisco Intercompany Media Engine provides features that help customers manage the QoS on the Internet, such as the ability to monitor QoS of the RTP traffic in real-time and fallback to PSTN automatically if problems arise.

How the UC-IME Works with the PSTN and the Internet

The Cisco Intercompany Media Engine utilizes two networks that both have worldwide reach—the

Internet and the PSTN. Customers continue to use the PSTN connectivity they have. The Cisco

Intercompany Media Engine gradually moves calls off the PSTN and onto the Internet. However, if QoS problems arise, the Cisco Intercompany Media Engine Proxy monitors QoS of the RTP traffic in real-time and fallbacks to PSTN automatically.

The Cisco Intercompany Media Engine uses information from PSTN calls to validate that the terminating side owns the number that the originated side had called. After the PSTN call terminates, the enterprises involved in the call send information about the call to their Cisco IME server. The Cisco

IME server on the originating side validates the call.

Figure 47-1 shows the initial call flow through the

PSTN.

47-2


OL-20339-01



On successful verification, the terminating side creates a ticket that grants permission to the call originator to make a Cisco IME call to a specific number. See

Tickets and Passwords, page 47-3 for

information.

Figure 47-1 Interaction of the UC-IME Proxy with the PSTN

Enterpri s e A

IP

UC-IME

S erver

Ci s co UCM

M

IP

A S A

P ub lic

Internet

A S A

Enterpri s e B

UC-IME

S erver

Ci s co UCM

IP

M

IP

P S TN

Tickets and Passwords

Cisco Intercompany Media Engine utilizes tickets and passwords to provide enterprise verification.

Verification through the creation of tickets ensures an enterprise is not subject to denial-of-service

(DOS) attacks from the Internet or endless VoIP spam calls. Ticket verification prevents spam and DOS attacks because it introduces a cost to the VoIP caller; namely, the cost of a PSTN call. A malicious user cannot set up just an open source asterisk PBX on the Internet and begin launching SIP calls into an enterprise running Cisco Intercompany Media Engine. Having the Cisco Intercompany Media Engine

Proxy verify tickets allows incoming calls from a particular enterprise to a particular number only when that particular enterprise has previously called that phone number on the PSTN.

To send a spam VoIP call to every phone within an enterprise, an organization would have to purchase the Cisco Intercompany Media Engine and Cisco Unified Communications Manager and have called each phone number within the enterprise over the PSTN and completed each call successfully. Only then can it launch a VoIP call to each number.

The Cisco Intercompany Media Engine server creates tickets and the adaptive security appliance validates them. The adaptive security appliance and Cisco Intercompany Media Engine server share a password that is configured so that the adaptive security appliance detects the ticket was created by a trusted Cisco Intercompany Media Engine server. The ticket contains information that indicates that the enterprise is authorized to call specific phone numbers at the target enterprise. See

Figure 47-2 for the

ticket verification process and how it operates between the originating and terminating-call enterprises.

Note

Because the initial calls are over the PSTN, they are subject to any national regulations regarding telemarketing calling. For example, within the United States, they would be subject to the national do-not-call registry.

OL-20339-01


47-3



Figure 47-2

Enterpri s e A

M

Ci s co UCM

IP

Ticket Verification Process with Cisco Intercompany Media Engine

UC-IME

S erver

1

Enterpri s e B get s au thoriz a tion ticket from A a t end of v a lid a tion protocol

Internet

Enterpri s e B

UC-IME

S erver

2

UC-IME s erver p ass e s ticket to UCM a nd it’ s s tored as p a rt of VoIP ro u te

M

Ci s co UCM

IP

4

A S A

A S A v a lid a te s ticket

Enterpri s e B c a ll s A a nd incl u de s ticket

3

A S A

IP

IP

As illustrated in Figure 47-2 . Enterprise B makes a PSTN call to enterprise A. That call completes

successfully. Later, Enterprise B Cisco Intercompany Media Engine server initiates validation procedures with Enterprise A. These validation procedures succeed. During the validation handshake,

Enterprise B sends Enterprise A its domain name. Enterprise A verifies that this domain name is not on the blacklisted set of domains. Assuming it is not, Enterprise A creates a ticket.

Subsequently, someone in Enterprise B calls that number again. That call setup message from Enterprise

B to Enterprise A includes the ticket in the X-Cisco-UC-IME-Ticket header field in the SIP INVITE message. This message arrives at the Enterprise A adaptive security appliance. The adaptive security appliance verifies the signature and computes several checks on the ticket to make sure it is valid. If the ticket is valid, the adaptive security appliance forwards the request to Cisco UCM (including the ticket).

Because the adaptive security appliance drops requests that lack a valid ticket, unauthorized calls are never received by Cisco UCM.

The ticket password is a 128 bit random key, which can be thought of as a shared password between the adaptive security appliance and the Cisco Intercompany Media Engine server. This password is generated by the Cisco Intercompany Media Engine server and is used by a Cisco Intercompany Media

Engine SIP trunk to generate a ticket to allow a call to be made between Cisco Intercompany Media

Engine SIP trunks. A ticket is a signed object that contains a number of fields that grant permission to the calling domain to make a Cisco Intercompany Media Engine call to a specific number. The ticket is signed by the ticket password.

The Cisco Intercompany Media Engine also required that you configure an epoch for the password. The epoch contains an integer that updates each time that the password is changed. When the proxy is configured the first time and a password entered for the first time, enter 1 for the epoch integer. Each time you change the password, increment the epoch to indicate the new password. You must increment the epoch value each time your change the password.

Typically, you increment the epoch sequentially; however, the adaptive security appliance allows you to choose any value when you update the epoch. If you change the epoch value, the tickets in use at remote enterprises become invalid. The incoming calls from the remote enterprises fallback to the PSTN until the terminating enterprise reissues tickets with the new epoch value and password.

The epoch and password that you configure on the adaptive security appliance must match the epoch and password configured on the Cisco Intercompany Media Engine server. If you change the password or epoch on the adaptive security appliance, you must update them on the Cisco Intercompany Media

Engine server. See the Cisco Intercompany Media Engine server documentation for information.

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Call Fallback to the PSTN

Cisco Intercompany Media Engine provides features that manage the QoS on the Internet, such as the ability to monitor QoS of the RTP traffic in real-time and fallback to PSTN automatically if problems arise. Call fallback from Internet VoIP calls to the public switched telephone network (PSTN) can occur for two reasons changes in connection quality and signal failure for the Cisco Intercompany Media

Engine.

Internet connections can vary wildly in their quality and vary over time. Therefore, even if a call is sent over VoIP because the quality of the connection was good, the connection quality might worsen mid-call.

To ensure an overall good experience for the end user, Cisco Intercompany Media Engine attempts to perform a mid-call fallback.

Performing a mid-call fallback requires the adaptive security appliance to monitor the RTP packets coming from the Internet and send information into an RTP Monitoring Algorithm (RMA) API, which will indicates to the adaptive security appliance whether fallback is required. If fallback is required, the adaptive security appliance sends a REFER message to Cisco UCM to tell it that it needs to fallback the call to PSTN.

The TLS signaling connections from the Cisco UCM are terminated on the adaptive security appliance and a TCP or TLS connection is initiated to the Cisco UCM. SRTP (media) sent from external IP phones to the internal network IP phone via the adaptive security appliance is converted to RTP. The adaptive security appliance inserts itself into the media path by modifying the SIP signaling messages that are sent over the SIP trunk between Cisco UCMs. TLS (signaling) and SRTP are always terminated on the adaptive security appliance.

If signaling problems occur, the call falls back to the PSTN; however, the Cisco UCM initiates the PSTN fall back and the adaptive security appliance does not send REFER message.

Architecture and Deployment Scenarios for Cisco Intercompany Media Engine


•

•

•

Architecture, page 47-5

Basic Deployment, page 47-6

Off Path Deployment, page 47-7

Architecture

Within the enterprise, Cisco Intercompany Media Engine is deployed with the following components for the following purposes:

•

•

•

The adaptive security appliance—Enabled with the Cisco Intercompany Media Engine Proxy, provides perimeter security functions and inspects SIP signaling between SIP trunks.

Cisco Intercompany Media Engine (UC-IME) server— Located in the DMZ, provides an automated provisioning service by learning new VoIP routes to particular phone numbers, and recording those routes in Cisco UCM. The Cisco Intercompany Media Engine server does not perform call control.

Cisco Unified Communications Manager (Cisco UCM)—Responsible for call control and processing. Cisco UCM connects to the Cisco Intercompany Media Engine server by using the

Access Protocol to publish and exchange updates. The architecture can consist of a single Cisco

UCM or a Cisco UCM cluster within the enterprise.

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47-5



•

Cisco Intercompany Media Engine (UC-IME) Bootstrap server—Provides a certificate required admission onto the public peer-to-peer network for Cisco Intercompany Media Engine.

Figure 47-3

illustrates the components of the Cisco Intercompany Media Engine in a basic deployment.

Figure 47-3 Cisco Intercompany Media Engine Architecture in a Basic Deployment

In s ide Enterpri s e DMZ Out s ide Enterpri s e

Ci s co UCM Cl us ter

M

M

M

M M

UC-IME

Boot s tr a p S erver

UC-IME

Acce ss Protocol

TCP/TL S

UC-IME S erver

A S A En ab led with

UC-IME Proxy

Peer-to-peer

V a lid a tion

S IP/TL S

S IP/ S CCP

IP

RTP/ S RTP

S RTP

IP

IP

Basic Deployment

In a basic deployment, the Cisco Intercompany Media Engine Proxy sits in-line with the Internet firewall such that all Internet traffic traverses the adaptive security appliance. In this deployment, a single Cisco

UCM or a Cisco UCM cluster is centrally deployed within the enterprise, along with a Cisco

Intercompany Media Engine server (and perhaps a backup).

As shown in

Figure 47-4

, the adaptive security appliance sits on the edge of the enterprise and inspects

SIP signaling by creating dynamic SIP trunks between enterprises.

47-6


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Figure 47-4

Enterpri s e A

Basic Deployment Scenario

UC-IME


Enterpri s e B

M

Ci s co UCM

UC-IME

S erver

A S A En ab led with UC-IME Proxy

IP

IP

V

P S TN G a tew a y

Internet

S IP Tr u nk

P S TN

UC-IME

S erver

M

Ci s co UCM

A S A En ab led with UC-IME Proxy

IP

IP

V

P S TN G a tew a y

Off Path Deployment

In an off path deployment, inbound and outbound Cisco Intercompany Media Engine calls pass through an adaptive security appliance enabled with the Cisco Intercompany Media Engine Proxy. The adaptive security appliance is located in the DMZ and is configured to support only the Cisco Intercompany

Media Engine traffic (SIP signaling and RTP traffic). Normal Internet facing traffic does not flow through this adaptive security appliance.

For all inbound calls, the signaling is directed to the adaptive security appliance because destined Cisco

UCMs are configured with the global IP address on the adaptive security appliance. For outbound calls, the called party could be any IP address on the Internet; therefore, the adaptive security appliance is configured with a mapping service that dynamically provides an internal IP address on the adaptive security appliance for each global IP address of the called party on the Internet.

Cisco UCM sends all outbound calls directly to the mapped internal IP address on the adaptive security appliance instead of the global IP address of the called party on the Internet. The adaptive security appliance then forwards the calls to the global IP address of the called party.

Figure 47-5 illustrates the architecture of the Cisco Intercompany Media Engine in an off path

deployment.

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47-7


Licensing for Cisco Intercompany Media Engine

Figure 47-5 Off Path Deployment of the Adaptive Security Appliance

In s ide Enterpri s e DMZ

UC-IME

S erver

Out s ide Enterpri s e

UC-IME


Ci s co UCM Cl us ter

M

M

M

Internet

M M

IP

IP

IP

Intr a net

Firew a ll

A S A en ab led with UC-IME proxy

Only UC-IME c a ll s p ass thro u gh the A S A en ab led with the UC-IME proxy.

Internet

Firew a ll

V

P S TN

G a tew a y

P S TN

Licensing for Cisco Intercompany Media Engine

The Cisco Intercompany Media Engine feature supported by the adaptive security appliance require a

Unified Communications Proxy license.

The following table shows the details of the Unified Communications Proxy license:

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Model

All models


Intercompany Media Engine license.

When you enable the Intercompany Media Engine (IME) license, you can use TLS proxy sessions up to the platform limit. If you also install the Unified Communications (UC) license, then the sessions available for UC are also available for IME sessions. For example, if the platform limit is 1000 TLS proxy sessions, and you purchase a 750-session UC license, then the first 250 IME sessions do not affect the sessions available for UC. If you need more than 250 sessions for IME, then the remaining

750 sessions of the platform limit are used on a first-come, first-served basis by UC and IME.

The maximum number of IME sessions you can use depends on the TLS proxy session limit:

•

Note


For a license part number ending in “K9”, the TLS proxy limit depends on your configuration and the platform model. To configure the TLS proxy limit, use the Configuration > Firewall >

Unified Communications > TLS Proxy pane.K8 and K9 refer to whether the license is restricted for export: K8 is unrestricted, and K9 is restricted.


•

•

Note








Supported in single context mode only.


Supported in routed firewall mode only.

IPv6 Guidelines

Does not support IPv6 addresses.


Cisco Intercompany Media Engine has the following limitations:

•

Fax is not supported. Fax capability needs to be disabled on the SIP trunk.

•

Stateful failover of Cisco Unified Intercompany Media Engine is not supported. During failover, existing calls traversing the Cisco Intercompany Media Engine Proxy disconnect; however, new calls successfully traverse the proxy after the failover completes.

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47-9



•

•

•

•

•

•

•

Having Cisco UCMs on more than one of the adaptive security appliance interfaces is not supported with the Cisco Intercompany Media Engine Proxy. Having the Cisco UCMs on one trusted interface is especially necessary in an off path deployment because the adaptive security appliance requires that you specify the listening interface for the mapping service and the Cisco UCMs must be connected on one trusted interface.

Multipart MIME is not supported.

Only existing SIP features and messages are supported.

RTCP is not supported. The adaptive security appliance drops any RTCP traffic sent from the inside interface to the outside interface. The adaptive security appliance does not convert RTCP traffic from the inside interface into SRTP traffic.

The Cisco Intercompany Media Engine Proxy configured on the adaptive security appliance creates a dynamic SIP trunk for each connection to a remote enterprise. However, you cannot configure a unique subject name for each SIP trunk. The Cisco Intercompany Media Engine Proxy can have only one subject name configured for the proxy.

Additionally, the subject DN you configure for the Cisco Intercompany Media Engine Proxy match the domain name that has been set for the local Cisco UCM.

If a service policy rule for the Cisco Intercompany Media Engine Proxy is removed (by using the no service policy command) and reconfigured, the first call traversing the adaptive security appliance will fail. The call fails over to the PSTN because the Cisco UCM does not know the connections are cleared and tries to use the recently cleared IME SIP trunk for the signaling.

To resolve this issue, you must additionally enter the

clear connection all

command and restart the adaptive security appliance. If the failure is due to failover, the connections from the primary adaptive security appliance are not synchronized to the standby adaptive security appliance.

After the


command is issued on an adaptive security appliance enabled with a

UC-IME Proxy and the IME call fails over to the PSTN, the next IME call between an originating and terminating SCCP IP phone completes but does not have audio and is dropped after the signaling session is established.

An IME call between SCCP IP phones use the IME SIP trunk in both directions. Namely, the signaling from the calling to called party uses the IME SIP trunk. Then, the called party uses the reverse IME SIP trunk for the return signaling and media exchange. However, this connection is already cleared on the adaptive security appliance, which causes the IME call to fail.

The next IME call (the third call after the


command is issued), will be completely successful.

Note

This limitation does not apply when the originating and terminating IP phones are configured with SIP.

•

The adaptive security appliance must be licensed and configured with enough TLS proxy sessions to handle the IME call volume. See Licensing for Cisco Intercompany Media Engine for information about the licensing requirements for TLS proxy sessions.

This limitation occurs because an IME call cannot fall back to the PSTN when there are not enough

TLS proxy sessions left to complete the IME call. An IME call between two SCCP IP phones requires the adaptive security appliance to use two TLS proxy sessions to successfully complete the

TLS handshake.

Assume for example, the adaptive security appliance is configured to have a maximum of 100 TLS proxy sessions and IME calls between SCCP IP phones establish 101 TLS proxy sessions. In this example, the next IME call is initiated successfully by the originating SCCP IP phone but fails after

47-10


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the call is accepted by the terminating SCCP IP phone. The terminating IP phone rings and on answering the call, the call hangs due to an incomplete TLS handshake. The call does not fall back to the PSTN.



•

•

•

•

•

•

•

•

•

•

•

Task Flow for Configuring Cisco Intercompany Media Engine, page 47-11

Configuring NAT for Cisco Intercompany Media Engine Proxy, page 47-12

Configuring PAT for the Cisco UCM Server, page 47-14

Creating Access Lists for Cisco Intercompany Media Engine Proxy, page 47-16

Creating the Media Termination Instance, page 47-17

Creating the Cisco Intercompany Media Engine Proxy, page 47-18

Creating Trustpoints and Generating Certificates, page 47-22

Creating the TLS Proxy, page 47-25

Enabling SIP Inspection for the Cisco Intercompany Media Engine Proxy, page 47-26

(Optional) Configuring TLS within the Local Enterprise, page 47-28

(Optional) Configuring Off Path Signaling, page 47-31

Task Flow for Configuring Cisco Intercompany Media Engine

Figure 47-6 provides an example for a basic deployment of the Cisco Intercompany Media Engine. The following tasks include command line examples based on Figure 47-6 .

Figure 47-6 Example for Basic (in-line) Deployment Tasks

Local Enterpri s e

Loc a l

Ci s co UCM s

Loc a l

UC-IME

S erver

UC-IME

Boot s tr a p

S erver

M

M

192.16

8 .10.

3 0

192.16

8 .10.

3 1

Corpor a te

Network

IP

TCP

IP

192.16

8 .10.12

IP

A S A in s ide interf a ce

192.16

8 .10.1

In s ide medi a termin a tion

192.16

8 .10.

3

A S A o u t s ide interf a ce

209.165.200.225

TL S

Internet

Loc a l A S A

O u t s ide medi a termin a tion

209.165.200.226

O u t s ide Ci s co UMC

209.165.200.22

8

Remote Enterpri s e

Remote

UC-IME

S erver

Remote A S A

M

Remote

Ci s co UCM

Note

Step 1 through Step 8 apply to both basic (in-line) and off path deployments and Step 9 applies only to off path deployment.

OL-20339-01


47-11



To configure a Cisco Intercompany Media Engine for a basic deployment, perform the following tasks.

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Configure static NAT for Cisco UCM. See Configuring NAT for Cisco Intercompany Media Engine

Proxy, page 47-12 .

Or

Configure PAT for the UCM server. See Configuring PAT for the Cisco UCM Server, page 47-14 .

Create access lists for Cisco Intercompany Media Engine Proxy. See Creating Access Lists for Cisco


Create the media termination address instance for Cisco Intercompany Media Engine Proxy. See

Creating the Media Termination Instance, page 47-17 .

Create the Cisco Intercompany Media Engine Proxy. See Creating the Cisco Intercompany Media

Engine Proxy, page 47-18 .

Create trustpoints and generate certificates for the Cisco Intercompany Media Engine Proxy. See

Creating Trustpoints and Generating Certificates, page 47-22 .

Create the TLS proxy. See Creating the TLS Proxy, page 47-25 .

Configure SIP inspection for the Cisco Intercompany Media Engine Proxy. See Enabling SIP Inspection for the Cisco Intercompany Media Engine Proxy, page 47-26 .

(Optional) Configure TLS within the enterprise. See (Optional) Configuring TLS within the Local

Enterprise, page 47-28 .

(Optional) Configure off path signaling. See (Optional) Configuring Off Path Signaling, page 47-31 .

Note

You only perform Step 9 when you are configuring the Cisco Intercompany Media Engine Proxy in an off path deployment.

Configuring NAT for Cisco Intercompany Media Engine Proxy

To configure auto NAT, you first configure an object; then use the

nat

command in the object configuration mode.

The example command lines in this task are based on a basic (in-line) deployment. See Figure 47-6 on page 47-11 for an illustration explaining the example command lines in this task.

Alternatively, you can configure PAT for the Cisco Intercompany Media Engine Proxy. See Configuring

PAT for the Cisco UCM Server, page 47-14 .

47-12


OL-20339-01



Figure 47-7 Example for Configuring NAT for a Deployment


Loc a l Ci s co UCM s

192.16

8 .10.

3 0

199.16

8 .10.

3 1

Config

192.16

192.16

u

8

8 re NAT:

.10.

.10.

3

3

0

1

209.165.200.22

8

209.165.200.22

8

M

TCP

Corpor a te

Network

M

IP

IP

IP

TL S

Internet

Loc a l A S A

O u t s ide Ci s co UCM a ddre ss

209.165.200.22

8

To configure auto NAT rules for the Cisco UCM server, perform the following steps:

Command

Step 1

hostname(config)#

object network

name

Examples:

hostname(config)# object network ucm_real_192.168.10.30 hostname(config)# object network ucm_real_192.168.10.31

Step 2

hostname(config-network-object)#

host

ip_address

Examples:

hostname(config-network-object)# host 192.168.10.30


Step 3

(Optional) hostname(config-network-object)#

description

string

Example:

hostname(config-network-object)# description “Cisco

UCM Real Address”

Step 4


exit

Step 5

hostname(config)#

object network

name

Example:

hostname(config)# object network ucm_map_209.165.200.228

Step 6


host

ip_address

Example:

hostname(config-network-object)# host

209.165.200.228

Step 7

(Optional) hostname(config-network-object)#

description

string

Example:

hostname(config-network-object)# description “Cisco

UCM Mapped Address”

Purpose

Configures a network object for the real address of

Cisco UCM that you want to translate.

Specifies the real IP address of the Cisco UCM host for the network object.

Provides a description of the network object.

Exits from the objects configuration mode.

Configures a network object for the mapped address of the Cisco UCM.

Specifies the mapped IP address of the Cisco UCM host for the network object.

Provides a description of the network object.

OL-20339-01


47-13



Command

Step 8


exit

Purpose


Step 9

hostname(config)#

nat (inside,outside) source static

real_obj mapped_obj

Examples:

hostname(config)# nat (inside,outside) source static ucm_real_192.168.10.30 ucm_209.165.200.228

hostname(config)# nat (inside,outside) source static ucm_real_192.168.10.31 ucm_209.165.200.228

Specifies the address translation on the network objects created in this procedure.

Where

real_obj

is the

name

that you created in

Step 1 in this task.

Where

mapped_obj

is the

name

that you created in

Step 5 in this task.

What to Do Next

Create the access lists for the Cisco Intercompany Media Engine Proxy. See Creating Access Lists for

Cisco Intercompany Media Engine Proxy, page 47-16 .

Configuring PAT for the Cisco UCM Server

Perform this task as an alternative to configuring NAT for the Cisco Intercompany Media Engine Proxy.

Figure 47-8 Example for Configuring PAT for a Deployment


Loc a l Ci s co UCM s

192.16

8 .10.

3 0

199.16

8 .10.

3 1

Config

192.16

192.16

u

8

8 re PAT:

.10.

.10.

3

3

0:5070

1:5071

M

TCP

Corpor a te

Network

M

IP

IP

IP

TL S

209.165.200.22

8 :5570

209.165.200.22

8 :5571

Loc a l A S A

O u t s ide Ci s co UCM a ddre ss

209.165.200.22

8

Internet

Note

You only perform this step when NAT is not configured for the Cisco UCM server.

To configure PAT for the Cisco UCM server, perform the following steps:

47-14


OL-20339-01



Command

Step 1

hostname(config)#

object network

name

Examples:

hostname(config)# object network ucm-pat-209.165.200.228

Step 2


host

ip_address

Example:

hostname(config-network-object)# host

209.165.200.228

Step 3


exit

Step 4

hostname(config)#

object service

name

Examples:

hostname(config)# object service tcp_5070 hostname(config)# object service tcp_5071

Step 5

hostname(config-service-object)#

tcp source eq

port

Examples:

hostname(config-service-object)# tcp source eq 5070 hostname(config-service-object)# tcp source eq 5071

Step 6


exit

Step 7

hostname(config)#

object network

name

Examples:

hostname(config)# object network ucm-real-192.168.10.30

hostname(config)# object network ucm-real-192.168.10.31

Step 8


host

ip_address

Examples:



Step 9


exit

Step 10

hostname(config)#

object service

name

Examples:

hostname(config)# object service tcp_5570 hostname(config)# object service tcp_5571

Step 11


tcp source eq

port

Example:

hostname(config-service-object)# tcp source eq 5570 hostname(config-service-object)# tcp source eq 5571

Purpose

Configures a network object for the outside IP address of Cisco UCM that you want to translate.



Creates a service object for the outside Cisco

Intercompany Media Engine port.

Specifies the port number.


Configures a network object to represent the real IP address of Cisco UCM.



Creates a service objects for Cisco UCM SIP port.

Specifies the port number.

Step 12


exit


Step 13

hostname(config)#

nat (inside,outside) source static

real_obj mapped_obj

service

real_port mapped_port

Examples:

hostname(config)# nat (inside,outside) source static ucm-real-192.168.10.30 ucm-pat-209.165.200.228 service tcp_5070 tcp_5570 hostname(config)# nat (inside,outside) source static ucm-real-192.168.10.31 ucm-pat-128.106.254.5 service tcp_5071 tcp_5571

Creates a static mapping for Cisco UCM.

Where real_obj is the name that you created in

Step 1 in this task.

Where mapped_obj is the name that you created in


Where real_port is the name that you created in


Where mapped_obj is the name that you created in


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47-15



Creating Access Lists for Cisco Intercompany Media Engine Proxy

To configure access lists for the Cisco Intercompany Media Engine Proxy to reach the Cisco UCM server, perform the following steps.


Command Purpose

Step 1

hostname(config)#

access-list

id

extended permit tcp any host

ip_address

eq

port

Example:

hostname(config)# access-list incoming extended permit tcp any host 192.168.10.30 eq 5070

Adds an Access Control Entry (ACE). An access list is made up of one or more ACEs with the same access list ID. This ACE provides access control by allowing incoming access for Cisco Intercompany

Media Engine connections on the specified port.

In the

ip_address

argument, provide the real IP address of Cisco UCM.

Step 2

hostname(config)#

access-group

access-list

in interface

interface_name

Example:

hostname(config)# access-group incoming in interface outside

Binds the access list to an interface.

Step 3

hostname(config)#

access-list

id

extended permit tcp any host

ip_address

eq

port

Example:

hostname(config)# access-list ime-inbound-sip extended permit tcp any host 192.168.10.30 eq 5070

Adds an ACE. This ACE allows the adaptive security appliance to allow inbound SIP traffic for

Cisco Intercompany Media Engine. This entry is used to classify traffic for the class and policy map.

Note

The port that you configure here must match the trunk settings configured on Cisco UCM.

See the Cisco Unified Communications

Manager documentation for information about this configuration setting.

Step 4

hostname(config)#

access-list

id

extended permit tcp

ip_address mask

any range

range

Example:

hostname(config)# access-list ime-outbound-sip extended permit tcp 192.168.10.30 255.255.255.255 any range 5000 6000

Adds an ACE. This ACE allows the adaptive security appliance to allow outbound SIP traffic for

Cisco Intercompany Media Engine (in the example, any TCP traffic with source as 192.168.10.30 and destination port range between 5000 and 6000). This entry is used to classify traffic for the class and policy map.

Note

Ensure that TCP traffic between Cisco UCM and the Cisco Intercompany Media Engine server does not use this port range (if that connection goes through the adaptive security appliance).

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Command

Step 5

hostname(config)#

access-list

id

permit tcp any host

ip_address

eq 6084

Example:

hostname(config)# access-list ime-traffic permit tcp any host 192.168.10.12 eq 6084

Purpose

Adds an ACE. This ACE allows the adaptive security appliance to allow traffic from the Cisco

Intercompany Media Engine server to remote Cisco

Intercompany Media Engine servers.

Step 6

hostname(config)#

access-list

id

permit tcp any host

ip_address

eq 8470

Example:

hostname(config)# access-list ime-bootserver-traffic permit tcp any host 192.168.10.12 eq 8470

Adds an ACE. This ACE allows the adaptive security appliance to allow traffic from the Cisco

Intercompany Media Engine server to the Bootstrap server for the Cisco Intercompany Media Engine.

What to Do Next

Create the media termination instance on the adaptive security appliance for the Cisco Intercompany

Media Engine Proxy. See Creating the Media Termination Instance, page 47-17 .

Creating the Media Termination Instance

Guidelines

The media termination address you configure must meet these requirements:

•

If you decide to configure a media-termination address on interfaces (rather than using a global interface), you must configure a media-termination address on at least two interfaces (the inside and an outside interface) before applying the service policy for the Cisco Intercompany Media Engine

Proxy. Otherwise, you will receive an error message when enabling the proxy with SIP inspection.

Note

Cisco recommends that you configure the media-termination address for the Cisco Intercompany

Media Engine Proxy on interfaces rather than configuring a global media-termination address.

•

Note

The Cisco Intercompany Media Engine Proxy can use only one type of media termination instance at a time; for example, you can configure a global media-termination address for all interfaces or configure a media-termination address for different interfaces. However, you cannot use a global media-termination address and media-termination addresses configured for each interface at the same time.

If you change any Cisco Intercompany Media Engine Proxy settings after you create the media-termination address for the proxy, you must reconfigure the media-termination address by using the

no media-termination

command, and then reconfiguring it as described in this procedure.

Procedure

Create the media termination instance to use with the Cisco Intercompany Media Engine Proxy.


To create the media termination instance for the Cisco Intercompany Media Engine Proxy, perform the following steps:

OL-20339-01


47-17



Command

Step 1

hostname(config)#

media-termination

instance_name

Example:

hostname(config)#


uc-ime-media-term

Step 2

hostname(config-media-termination)#

address

ip_address

interface

intf_name

Examples:

hostname(config-media-termination)# address

209.165.200.228 interface outside

Step 3

hostname(config-media-termination)#

address

ip_address

interface

intf_name

Examples:

hostname(config-media-termination)# address

192.168.10.3 interface inside

Step 4

(Optional) hostname(config-media-termination)#

rtp-min-port

port1

rtp-maxport

port2

Examples:

hostname(config-media-termination)# rtp-min-port

1000 rtp-maxport 2000

Purpose

Creates the media termination instance that you attach to the Cisco Intercompany Media Engine

Proxy.

Configures the media-termination address used by the outside interface of the adaptive security appliance.

The outside IP address must be a publicly routable address that is an unused IP address within the address range on that interface.

See Creating the Cisco Intercompany Media Engine

Proxy, page 47-18 for information about the

UC-IME proxy settings. See


Configuration Guide using the CLI


no service-policy

command.

Configures a media termination address used by the inside interface of the adaptive security appliance.

Note

The IP address must be an unused IP address within the same subnet on that interface.

Configures the rtp-min-port and rtp-max-port limits for the Cisco Intercompany Media Engine Proxy.

Configure the RTP port range for the media termination point when you need to scale the number of calls that the Cisco Intercompany Media

Engine supports.

Where

port1

specifies the minimum value for the

RTP port range for the media termination point, where port1 can be a value from 1024 to 65535. By default, the value for

port1

is 16384.

Where

port2

specifies the maximum value for the

RTP port range for the media termination point, where port2 can be a value from 1024 to 65535. By default, the value for

port2

is 32767.

What To Do Next

Once you have created the media termination instance, create the Cisco Intercompany Media Engine

Proxy. See Creating the Cisco Intercompany Media Engine Proxy, page 47-18 .

Creating the Cisco Intercompany Media Engine Proxy

To create the Cisco Intercompany Media Engine Proxy, perform the following steps.


47-18


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Note

You cannot change any of the configuration settings for the Cisco Intercompany Media Engine

Proxy described in this procedure when the proxy is enabled for SIP inspection. Remove the

Cisco Intercompany Media Engine Proxy from SIP inspection before changing any of the settings described in this procedure.

Command

Step 1

hostname(config)#

uc-ime

uc_ime_name

Example:

hostname(config)# uc-ime local-ent-ime

Step 2

hostname(config-uc-ime)#


mta_instance_name

Example:

hostname(config-uc-ime)# media-termination ime-media-term

Purpose

Configures the Cisco Intercompany Media Engine

Proxy.

Where

uc_ime_name

is the name of the Cisco

Intercompany Media Engine Proxy. The name is limited to 64 characters.

Only one Cisco Intercompany Media Engine Proxy can be configured on the adaptive security appliance.

Specifies the media termination instance used by the

Cisco Intercompany Media Engine Proxy.

Note

You must create the media termination instance before you specify it in the Cisco

Intercompany Media Engine Proxy.

Where

mta_instance_name

is the

instance_name

that you created in Step 1 of Creating the Media

Termination Instance .

See Creating the Media Termination Instance, page 47-17 for the steps to create the media termination instance.

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Command

Step 3


ucm address

ip_address

trunk-security-mode

[

nonsecure

|

secure

]

Example:

hostname(config-uc-ime)# ucm address 192.168.10.30 trunk-security-mode non-secure

Purpose

Specifies the Cisco UCM server in the enterprise.

You must specify the real IP address of the Cisco

UCM server. Do not specify a mapped IP address for the server.

Note

You must include an entry for each Cisco

UCM in the cluster with Cisco Intercompany

Media Engine that has a SIP trunk enabled.

Where the

nonsecure

and

secure

options specify the security mode of the Cisco UCM or cluster of Cisco

UCMs.

Note

Specifying

secure

for Cisco UCM or Cisco

UCM cluster indicates that Cisco UCM or

Cisco UCM cluster is initiating TLS; therefore, you must configure TLS for components. See (Optional) Configuring

TLS within the Local Enterprise, page 47-28 .

You can specify the

secure

option in this task or you can update it later while configuring TLS for the enterprise. See Step 11 in (Optional) Configuring

TLS within the Local Enterprise, page 47-28 .

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Command

Step 4


ticket epoch

n

password

password

Example:

hostname(config-uc-ime)# ticket epoch 1 password password1234


Purpose

Configures the ticket epoch and password for Cisco

Intercompany Media Engine.

Where

n

is an integer from 1-255. The epoch contains an integer that updates each time that the password is changed. When the proxy is configured the first time and a password entered for the first time, enter 1 for the epoch integer. Each time you change the password, increment the epoch to indicate the new password. You must increment the epoch value each time your change the password.

Typically, you increment the epoch sequentially; however, the adaptive security appliance allows you to choose any value when you update the epoch.


Where

password

contains a minimum of 10 and a maximum of 64 printable character from the

US-ASCII character set. The allowed characters include 0x21 to 0x73 inclusive, and exclude the space character.

We recommend a password of at least 20 characters.

Only one password can be configured at a time.

The ticket password is stored onto flash. The output of the

show running-config uc-ime

command displays ***** instead of the password string.

Note

The epoch and password that you configure on the adaptive security appliance must match the epoch and password configured on the Cisco Intercompany Media Engine server. See the Cisco Intercompany Media

Engine server documentation for information.

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Step 5

Step 6

Command

(Optional) hostname(config-uc-ime)#

fallback monitoring timer

timer_millisec

|

hold-down timer

timer_sec

Examples:

hostname(config-uc-ime)# fallback monitoring timer

120 hostname(config-uc-ime)# fallback hold-down timer 30

(Optional) hostname(config-uc-ime)#

fallback sensitivity-file

file_name

Example:

hostname(config-uc-ime)# fallback sensitivity-file ime-fallback-sensitvity.fbs

Purpose

Specifies the fallback timers for Cisco Intercompany

Media Engine.

Specifying

monitoring timer

sets the time between which the adaptive security appliance samples the

RTP packets received from the Internet. The adaptive security appliance uses the data sample to determine if fallback to the PSTN is needed for a call.

Where

timer_millisec

specifies the length of the monitoring timer. By default, the length is 100 milliseconds for the monitoring timer and the allowed range is 10-600 ms.

Specifying

hold-down timer

sets the amount of time that adaptive security appliance waits before notifying Cisco UCM whether to fall back to PSTN.

Where

timer_sec

specifies the length of the hold-down timer. By default, the length is 20 seconds for the hold-down timer and the allowed range is 10-360 seconds.

If you do not use this command to specify fallback timers, the adaptive security appliance uses the default settings for the fallback timers.

Specifies the file to use for mid-call PSTN fallback.

Where

file_name

must be the name of a file on disk that includes the .fbs file extension.

The fallback file is used to determine whether the

QoS of the call is poor enough for the Cisco

Intercompany Media Engine to move the call to the

PSTN.

What to Do Next

Install the certificate on the local entity truststore. You could also enroll the certificate with a local CA trusted by the local entity.

Creating Trustpoints and Generating Certificates

You need to generate the keypair for the certificate used by the adaptive security appliance, and configure a trustpoint to identify the certificate sent by the adaptive security appliance in the TLS handshake.


Note

This task instructs you on how to create trustpoints for the local enterprise and the remote enterprise and how to exchange certificates between these two enterprises. This task does not provide steps for creating trustpoints and exchanging certificates between the local Cisco UCM and the local adaptive security appliance. However, if you require additional security within the local enterprise, you must perform the

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optional task (Optional) Configuring TLS within the Local Enterprise, page 47-28 . Performing that task allows for secure TLS connections between the local Cisco UCM and the local adaptive security appliance. The instructions in that task describe how to create trustpoints between the local Cisco UCM and the local adaptive security appliance.

Prerequisites for Installing Certificates

To create a proxy certificate on the adaptive security appliance that is trusted by the remote entity, obtain a certificate from a trusted CA or export it from the remote enterprise adaptive security appliance.

To export the certificate from the remote enterprise, you enter the following command on the remote adaptive security appliance: hostname(config)#

crypto ca export trustpoint identity-certificate

The adaptive security appliance prompts displays the certificate in the terminal screen. Copy the certificate from the terminal screen. You will need the certificate text in Step 5 of this task.

Procedure

To create the trustpoints and generate certificates, perform the following steps:

Command

Step 1

hostname(config)#

crypto key generate rsa label

key-pair-label

modulus

size

Example:

hostname(config)# crypto key generate rsa label local-ent-key modulus 2048

Step 2

hostname(config)#

crypto ca trustpoint

trustpoint_name

Example:

hostname(config)# crypto ca trustpoint local_ent

Purpose

On the local adaptive security appliance, creates the RSA keypair that can be used for the trustpoints. This is the keypair and trustpoint for the local entities signed certificate.

The modulus key size that you select depends on the level of security that you want to configure and on any limitations imposed by the CA from which you are obtaining the certificate. The larger the number that you select, the higher the security level will be for the certificate. Most

CAs recommend 2048 for the key modulus size; however,

Note

GoDaddy requires a key modulus size of

2048.

Enters the trustpoint configuration mode for the specified trustpoint so that you can create the trustpoint for the local entity.

A trustpoint represents a CA identity and possibly a device identity, based on a certificate issued by the CA. Maximum name length is 128 characters.

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Command

Step 3

hostname(config-ca-trustpoint)#

subject-name

X.500_name

Example:

hostname(config-ca-trustpoint)# subject-name cn=Ent-local-domain-name**

Purpose

Includes the indicated subject DN in the certificate during enrollment.

Note

The domain name that you enter here must match the domain name that has been set for the local Cisco UCM.

For information about how to configure the domain name for Cisco UCM, see the

Cisco Unified Communications

Manager documentation for information.

Specifies the key pair whose public key is to be certified.

Step 4


keypair

keyname

Example:

hostname(config-ca-trustpoint)# keypair local-ent-key

Step 5


enroll terminal

Step 6


exit

Step 7

hostname(config)#

crypto ca enroll

trustpoint

Example:

hostname(config)# crypto ca enroll remote-ent

%

% Start certificate enrollment ...

% The subject name in the certificate will be:

% cn=enterpriseA

% The fully-qualified domain name in the certificate will

@ be: ciscoasa

% Include the device serial number in the subject name?

[yes/no]: no

Display Certificate Request to terminal? [yes/no]: yes

Specifies that you will use the “copy and paste” method of enrollment with this trustpoint (also known as manual enrollment).

Exits from the CA Trustpoint configuration mode.

Starts the enrollment process with the CA.

Where

trustpoint

entered for

is the same as the value you

trustpoint_name

in Step 2 .

When the trustpoint is configured for manual enrollment (

enroll terminal

command), the adaptive security appliance writes a base-64-encoded PKCS10 certification request to the console and then displays the CLI prompt.

Copy the text from the prompt.

Submit the certificate request to the CA, for example, by pasting the text displayed at the prompt into the certificate signing request enrollment page on the CA website.

Step 8

hostname(config)#

crypto ca import

trustpoint

certificate

Example:

hostname(config)# crypto ca import remote-ent certificate

When the CA returns the signed identity certificate, proceed to Step 8 in this procedure.

Imports the signed certificate received from the

CA in response to a manual enrollment request.

Where

trustpoint

specifies the trustpoint you created in Step 2 .

The adaptive security appliance prompts you to paste the base-64 formatted signed certificate onto the terminal.

Step 9

hostname(config)#


trustpoint

Example:

hostname(config)# crypto ca authenticate remote-ent

Authenticates the third-party identity certificate received from the CA. The identity certificate is associated with a trustpoint created for the remote enterprise.

The adaptive security appliance prompts you to paste the base-64 formatted identity certificate from the CA onto the terminal.

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What to Do Next

Create the TLS proxy for the Cisco Intercompany Media Engine. See the “Creating the TLS Proxy” section on page 47-25 .

Creating the TLS Proxy

Because either enterprise, namely the local or remote Cisco UCM servers, can initiate the TLS handshake (unlike IP Telephony or Cisco Mobility Advantage, where only the clients initiate the TLS handshake), you must configure by-directional TLS proxy rules. Each enterprise can have an adaptive security appliance as the TLS proxy.

Create TLS proxy instances for the local and remote entity initiated connections respectively. The entity that initiates the TLS connection is in the role of “TLS client.” Because the TLS proxy has a strict definition of “client” and “server” proxy, two TLS proxy instances must be defined if either of the entities could initiate the connection.


To create the TLS proxy, perform the following steps:

Command

Step 1

hostname(config)#

tls-proxy

proxy_name

Example:

hostname(config)# tls-proxy local_to_remote-ent

Step 2

hostname(config-tlsp)#

client trust-point

proxy_trustpoint

Example:

hostname(config-tlsp)# client trust-point local-ent

Step 3


client cipher-suite

cipher_suite

Example:

hostname(config-tlsp)# client cipher-suite aes128-sha1 aes256-sha1 3des-sha1 null-sha1

Step 4


exit

Step 5

hostname(config)#

tls-proxy

proxy_name

Example:

hostname(config)# tls-proxy remote_to_local-ent

Purpose

Creates the TLS proxy for the outbound connections.

For

outbound

connections, specifies the trustpoint and associated certificate that the adaptive security appliance uses in the TLS handshake when the adaptive security appliance assumes the role of the

TLS client. The certificate must be owned by the adaptive security appliance (identity certificate).

Where

proxy_trustpoint

specifies the trustpoint defined by the


command in

Step 2 in “Creating Trustpoints and Generating

Certificates” section on page 47-22 .

For outbound connections, controls the TLS handshake parameter for the cipher suite.

Where

cipher_suite

includes des-sha1, 3des-sha1, aes128-sha1, aes256-sha1, or null-sha1.

For client proxy (the proxy acts as a TLS client to the server), the user-defined cipher suite replaces the default cipher suite, or the one defined by the

ssl encryption

command. Use this command to achieve difference ciphers between the two TLS sessions.

You should use AES ciphers with the Cisco UCM server.

Exits from the TLS proxy configuration mode.

Create the TLS proxy for inbound connections.

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Command

Step 6


server trust-point

proxy_trustpoint

Example:

hostname(config-tlsp)# server trust-point local-ent

Step 7



cipher_suite

Example:

hostname(config-tlsp)# client cipher-suite aes128-sha1 aes256-sha1 3des-sha1 null-sha1

Step 8


exit

Step 9

hostname(config)# ssl encryption 3des-sha1 aes128-sha1 [

algorithms

]

Purpose

For

inbound

connections, specifies the proxy trustpoint certificate presented during TLS handshake. The certificate must be owned by the adaptive security appliance (identity certificate).

Where

proxy_trustpoint

specifies the trustpoint defined by the


command in

Step 2 in “Creating Trustpoints and Generating

Certificates” section on page 47-22 .

Because the TLS proxy has strict definition of client proxy and server proxy, two TLS proxy instances must be defined if either of the entities could initiate the connection.

For inbound connections, controls the TLS handshake parameter for the cipher suite.

Where

cipher_suite

includes des-sha1, 3des-sha1, aes128-sha1, aes256-sha1, or null-sha1.

Exits from the TSL proxy configuration mode.

Specifies the encryption algorithms that the

SSL/TLS protocol uses. Specifying the 3des-shal and aes128-shal is required. Specifying other algorithms is optional.

Note

The Cisco Intercompany Media Engine

Proxy requires that you use strong encryption. You must specify this command when the proxy is licensed using a K9 license.

What to Do Next

Once you have created the TLS proxy, enable it for SIP inspection.

Enabling SIP Inspection for the Cisco Intercompany Media Engine Proxy

Enable the TLS proxy for SIP inspection and define policies for both entities that could initiate the connection.


Note

If you want to change any Cisco Intercompany Media Engine Proxy settings after you enable SIP inspection, you must enter the


command, and then reconfigure the service policy as described in this procedure. Removing and reconfiguring the service policy does not affect existing calls; however, the first call traversing the Cisco Intercompany Media Engine Proxy will fail. Enter the

clear connection

command and restart the adaptive security appliance.

To enable SIP inspection for the Cisco Intercompany Media Engine Proxy, perform the following steps:

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Command

Step 1

hostname(config)#

class-map

class_map_name

Examples:

hostname(config)# class-map ime-inbound-sip

Step 2

hostname(config-cmap)#


access_list_name

Examples:

hostname(config-cmap)# match access-list ime-inbound-sip

Step 3


exit

Step 4

hostname(config)#

class-map

class_map_name

Examples:

hostname(config)# class-map ime-outbound-sip

Step 5

hostname(config)#


access_list_name

Examples:

hostname(config-cmap)# match access-list ime-outbound-sip

Step 6


exit

Step 7

hostname(config)#

policy-map

name

Examples:

hostname(config)# policy-map ime-policy

Step 8

hostname(config-pmap)#

class

classmap_name

Examples:

hostname(config-pmap)# class ime-outbound-sip

Purpose

Defines a class for the inbound Cisco Intercompany

Media Engine SIP traffic.

Identifies the SIP traffic to inspect.

Where the

access_list_name

is the access list you created in Step 3, page 47-16 of the task Creating

Access Lists for Cisco Intercompany Media Engine

Proxy .

Exits from the class map configuration mode.

Defines a class for the outbound SIP traffic from

Cisco Intercompany Media Engine.

Identifies which outbound SIP traffic to inspect.

Where the

access_list_name

is the access list you created in Step 4, page 47-16 of the task Creating

Access Lists for Cisco Intercompany Media Engine

Proxy .

Exits from the class map configuration mode.

Defines the policy map to which to attach the actions for the class of traffic.

Step 9

hostname(config-pmap-c)# inspect sip [sip_map] uc-ime

uc_ime_map

tls-proxy

proxy_name

Examples:

hostname(config-pmap-c)# inspect sip uc-ime local-ent-ime tls-proxy local_to_remote-ent

Step 10

hostname(config-cmap-c)#

exit

Step 11


class

class_map_name

Examples:

hostname(config-pmap)# class ime-inbound-sip

Step 12

hostname(config-pmap-c)# inspect sip [sip_map] uc-ime

uc_ime_map

tls-proxy

proxy_name

Examples:

hostname(config-pmap-c)# inspect sip uc-ime local-ent-ime tls-proxy remote_to_local-ent

Step 13

hostname(config-pmap-c)#

exit

Assigns a class map to the policy map so that you can assign actions to the class map traffic.

Where

classmap_name

is the name of the SIP class map that you created in Step 1 in this task.

Enables the TLS proxy and Cisco Intercompany

Media Engine Proxy for the specified SIP inspection session.

Exits from the policy map class configuration mode.

Assigns a class map to the policy map so that you can assign actions to the class map traffic.

Where

classmap_name

is the name of the SIP class map that you created in Step 4 in this task.

Enables the TLS proxy and Cisco Intercompany

Media Engine Proxy for the specified SIP inspection session.

Exits from the policy map class configuration mode.

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Command

Step 14


exit

Step 15

hostname(config)#

service-policy

policymap_name

global

Examples:

hostname(config)# service-policy ime-policy global

Purpose

Exits from the policy map configuration mode.

Enables the service policy for SIP inspection for all interfaces.

Where

policymap_name

is the name of the policy map you created in Step 7 of this task.

See Creating the Cisco Intercompany Media Engine

Proxy, page 47-18 for information about the

UC-IME proxy settings. See





command.

What to Do Next

Once you have enabled the TLS proxy for SIP inspection, if necessary, configure TLS within the enterprise. See (Optional) Configuring TLS within the Local Enterprise, page 47-28 .

(Optional) Configuring TLS within the Local Enterprise

This task is not required if TCP is allowable within the inside network.

TLS within the enterprise refers to the security status of the Cisco Intercompany Media Engine trunk as seen by the adaptive security appliance.

Note

If the transport security for the Cisco Intercompany Media Engine trunk changes on Cisco UCM, it must be changed on the adaptive security appliance as well. A mismatch will result in call failure. The adaptive security appliance does not support SRTP with non-secure IME trunks. The adaptive security appliance assumes SRTP is allowed with secure trunks. So ‘SRTP Allowed’ must be checked for IME trunks if TLS is used. The adaptive security appliance supports SRTP fallback to RTP for secure IME trunk calls.

Prerequisites

On the local Cisco UCM, download the Cisco UCM certificate. See the Cisco Unified Communications

Manager documentation for information. You will need this certificate when performing Step 6 of this procedure.

Procedure

To configure TLS within the local enterprise, perform the following steps on the local adaptive security appliance:

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Commands

Step 1

hostname(config)#

crypto key generate rsa label

key-pair-label

hostname(config)#


trustpoint_name


enroll self


keypair

keyname


subject-name

x.500_name

Example:

hostname(config)# crypto key generate rsa label local-ent-key hostname(config)# crypto ca trustpoint local-asa hostname(config-ca-trustpoint)# enroll self hostname(config-ca-trustpoint)# keypair key-local-asa hostname(config-ca-trustpoint)# subject-name

cn=Ent-local-domain-name**

., o="Example Corp"

Step 2


exit

Step 3

hostname(config)#

crypto ca export

trustpoint

identity-certificate

Example:

hostname(config)# crypto ca export local-asa identity-certificate

Step 4

hostname(config)#


trustpoint_name


enroll terminal

Example:

hostname(config)# crypto ca trustpoint local-ent-ucm hostname(config-ca-trustpoint)# enroll terminal

Step 5


exit

Purpose

Creates an RSA key and trustpoint for the self-signed certificate.

Where

key-pair-label

is the RSA key for the local adaptive security appliance.

Where

trustpoint_name

is the trustpoint for the local adaptive security appliance.

Where

keyname

is key pair for the local adaptive security appliance.

Where

x.500_name

includes the X.500 distinguished name of the local adaptive security appliance; for example,

cn=Ent-local-domain-name**

.

Note

The domain name that you enter here must match the domain name that has been set for the local Cisco UCM. For information about how to configure the domain name for Cisco

UCM, see the Cisco Unified

Communications Manager documentation for information.

Exits from Trustpoint Configuration mode.

Exports the certificate you created in Step 1 . The certificate contents appear on the terminal screen.

Copy the certificate from the terminal screen. This certificate enables Cisco UCM to validate the certificate that the adaptive security appliance sends in the TLS handshake.

On the local Cisco UCM, upload the certificate into the Cisco UCM trust store. See the Cisco Unified

Communications Manager documentation for information.

Note

The subject name you enter while uploading the certificate to the local Cisco UCM is compared with the X.509 Subject Name field entered on the SIP Trunk Security

Profile on Cisco UCM. For example,

“Ent-local-domain-name” was entered in

Step 1 of this task; therefore,

“Ent-local-domain-name” should be entered in the Cisco UCM configuration.

Creates a trustpoint for local Cisco UCM.

Where

trustpoint_name

local Cisco UCM.

is the trustpoint for the

Exits from Trustpoint Configuration mode.

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Commands

Step 6

hostname(config)#


trustpoint

Example:

hostname(config)# crypto ca authenticate local-ent-ucm

Step 7

hostname(config)#

tls-proxy

proxy_name



proxy_trustpoint



proxy_trustpoint



aes128-sha1 aes256-sha1 3des-sha1 null-sha1

Example:

hostname(config)# tls-proxy local_to_remote-ent hostname(config-tlsp)# server trust-point local-ent-ucm hostname(config-tlsp)# client trust-point local-ent hostname(config-tlsp)# client cipher-suite aes128-sha1 aes256-sha1 3des-sha1 null-sha1

Step 8


exit

Step 9

hostname(config)#

tls-proxy

proxy_name hostname(config-tlsp)#


proxy_trustpoint



proxy_trustpoint



aes128-sha1 aes256-sha1 3des-sha1 null-sha1

Example:

hostname(config)# tls-proxy remote_to_local-ent hostname(config-tlsp)# server trust-point local-ent hostname(config-tlsp)# client trust-point local-ent-ucm hostname(config-tlsp)# client cipher-suite aes128-sha1 aes256-sha1 3des-sha1 null-sha1

Step 10


exit

Step 11

hostname(config)#

uc-ime

uc_ime_name


ucm address

ip_address

trunk-security-mode secure

Example:

hostname(config)# uc-ime local-ent-ime hostname(config-uc-ime)# ucm address 192.168.10.30 trunk-security-mode secure

Purpose

Imports the certificate from local Cisco UCM.

Where

trustpoint

is the trustpoint for the local Cisco

UCM.

Paste the certificate downloaded from the local

Cisco UCM. This certificate enables the adaptive security appliance to validate the certificate that

Cisco UCM sends in the TLS handshake.

Updates the TLS proxy for

outbound

connections.

Where

proxy_name

is the name you entered in

Step 1 of the task Creating the TLS Proxy .

Where

proxy_trustpoint

for the


command is the name you entered in Step 4 of this procedure.

Where

proxy_trustpoint

for the


command is the name you entered in Step 2 of the task Creating Trustpoints and Generating

Certificates .

Note

In this step, you are creating different trustpoints for the client and the server.

Exits from TLS Proxy Configuration mode.

Updates the TLS proxy for

inbound

connections.

Where

proxy_name


Step 5 of the task Creating the TLS Proxy .

Where

proxy_trustpoint

for the


command is the name you entered in Step 2 of the task Creating Trustpoints and Generating

Certificates .

Where

proxy_trustpoint

for the


command is the name you entered in Step 4 of this procedure.

Exits from TLS Proxy Configuration mode.

Updates the Cisco Intercompany Media Engine

Proxy for trunk-security-mode.

Where

uc_ime_name


Step 1 of the task Creating the Cisco Intercompany

Media Engine Proxy .

Only perform this step if you entered nonsecure in

Step 3 of the task Creating the Cisco Intercompany

Media Engine Proxy .

What to Do Next

Once you have configured the TLS within the enterprise, if necessary, configure off path signaling for an off path deployment. See (Optional) Configuring Off Path Signaling, page 47-31 .

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(Optional) Configuring Off Path Signaling

Perform this task only when you are configuring the Cisco Intercompany Media Engine Proxy as part of an off path deployment. You might choose to have an off path deployment when you want to use the

Cisco Intercompany Media Engine but do not want to replace your existing Internet firewall with an adaptive security appliance enabled with the Cisco Intercompany Media Engine Proxy.

In an off path deployment, normal Internet facing trafficflows through the existing Internet firewall while the Cisco Intercompany Media Engine traffic flows through the adaptive security appliance enabled with the Cisco Intercompany Media Engine Proxy.

Off path signaling requires that outside IP addresses translate to an inside IP address. The inside interface address can be used for this mapping service configuration. For the Cisco Intercompany Media

Engine Proxy, the adaptive security appliance creates dynamic mappings for external addresses to the internal IP address; therefore, using the dynamic NAT configuration on outbound calls, Cisco UCM sends SIP traffic to this internal IP address, and the adaptive security appliance uses that mapping to determine the real destination on inbound calls. The static NAT or PAT mapping is used for inbound calls in an off path configuration.

Figure 47-9 Example for Configuring Off Path Signaling in an Off Path Deployment


OUT S IDE 0.0.0.0 0.0.0.0

192.16

8 .10.1

ip_address

:

port

Loc a l Ci s co UCM

A S A in s ide interf a ce

192.16

8 .10.1

M

Internet

TCP

TL S

Corpor a te

Network

Loc a l A S A O u t s ide Ci s co UCM a ddre ss

209.165.200.22

8

IP

IP

IP

After you configure off path signaling, the adaptive security appliance mapping service listens on interface “inside” for requests. When it receives a request, it creates a dynamic mapping for the “outside” as the destination interface.

To configure off path signaling for the Cisco Intercompany Media Engine Proxy, perform the following steps:

Command

Step 1

hostname(config)#

object network

name

Example:

hostname(config)# object network outside-any

Step 2


subnet

ip_address

Example:

hostname(config-network-object)# subnet 0.0.0.0

0.0.0.0

Step 3


nat inside dynamic interface

Purpose

For the off path adaptive security appliance, creates a network object to represent all outside addresses.

Specifies the IP address of the subnet.

Creates a mapping for the Cisco UCM of remote enterprises.

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Command

Step 4


exit

Step 5

hostname(config)#

uc-ime

uc_ime_name

Example:

hostname(config)# uc-ime local-ent-ime

Step 6


mapping-service listening-interface

interface_name

[

listening-port

port

]

uc-ime-interface

uc-ime-interface_name

Example:

hostname(config-uc-ime)# mapping-service listening-interface inside listening-port 8060 uc-ime-interface outside

Purpose


Specifies the Cisco Intercompany Media Engine

Proxy that you created in the task Creating the Cisco


Where

uc_ime_name

is the name you specified in

Step 1 of Creating the Cisco Intercompany Media

Engine Proxy, page 47-18 .

For the off path adaptive security appliance, adds the mapping service to the Cisco Intercompany Media

Engine Proxy.

Specifies the interface and listening port for the adaptive security appliance mapping service.

You can only configure one mapping server for the

Cisco Intercompany Media Engine Proxy.

Where

interface_name

is the name of the interface on which the adaptive security appliance listens for the mapping requests.

Where port is the TCP port on which the adaptive security appliance listens for the mapping requests.

The port number must be between 1024 and 65535 to avoid conflicts with other services on the device, such as Telnet or SSH. By default, the port number is TCP 8060.

Where

uc-ime-interface_name

is the name of the interface that connects to the remote Cisco UCM.

This section contains the following sections:

•

•

Configuring the Cisco UC-IMC Proxy by using the UC-IME Proxy Pane, page 47-32

Configuring the Cisco UC-IMC Proxy by using the Unified Communications Wizard, page 47-34

Configuring the Cisco UC-IMC Proxy by using the UC-IME Proxy Pane

Use the Configure Cisco Intercompany Media Engine (UC-IME) proxy pane to add or edit a Cisco

Intercompany Media Engine Proxy instance.

Note

The Cisco Intercompany Media Engine Proxy does not appear as an option under the Unified

Communications section of the navigation pane unless the license required for this proxy is installed on the adaptive security appliance.

Use this pane to create the proxy instance; however, for the UC-IME proxy to be fully functionally, you must complete additional tasks, such as create the required NAT statements, access lists, and MTA, set up the certificates, create the TLS Proxy, and enable SIP inspection.

Depending on whether the UC-IME proxy is deployed off path or in-line of Internet traffic, you must create the appropriate network objects with embedded NAT/PAT statements for the Cisco UCMs.

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This pane is available from the Configuration > Firewall > Unified Communications > UC-IME Proxy.

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Open the Configuration > Firewall > Unified Communications > UC-IME Proxy pane.

Check the Enable Cisco UC-IME proxy check box to enable the feature.

In the Unified CM Servers area, enter an IP address or hostname for the Cisco Unified Communications

Manager (Cisco UCM) or click the ellipsis to open a dialog and browse for an IP address or hostname.

In the Trunk Security Mode field, click a security option. Specifying

secure

for Cisco UCM or Cisco

UCM cluster indicates that Cisco UCM or Cisco UCM cluster is initiating TLS.

Click

Add

to add the Cisco UCM for the Cisco Intercompany Media Engine Proxy. You must include an entry for each Cisco UCM in the cluster with Cisco Intercompany Media Engine that has a SIP trunk enabled.

In the Ticket Epoch field, enter an integer from 1-255.

The epoch contains an integer that updates each time that the password is changed. When the proxy is configured the first time and a password entered for the first time, enter 1 for the epoch integer. Each time you change the password, increment the epoch to indicate the new password. You must increment the epoch value each time your change the password.

Typically, you increment the epoch sequentially; however, the adaptive security appliance allows you to choose any value when you update the epoch.


Note

The epoch and password that you configure in this step on the adaptive security appliance must match the epoch and password that you configure on the Cisco Intercompany Media Engine server. See the

Cisco Intercompany Media Engine server documentation for information.

Step 7

Step 8

In the Ticket Password field, enter a minimum of 10 printable character from the US-ASCII character set. The allowed characters include 0x21 to 0x73 inclusive, and exclude the space character. The ticket password can be up to 64 characters. Confirm the password you entered. Only one password can be configured at a time.

Check the Apply MTA to UC-IME Link proxy check box to associate the media termination address with the Cisco Intercompany Media Engine Proxy.

Note

You must create the media termination instance before you associate it with the Cisco

Intercompany Media Engine Proxy. If necessary, click the Configure MTA button to configure a media termination address instance.

Step 9

If the Cisco Intercompany Media Engine Proxy is being configured as part of off path deployment, check the Enable off path address mapping service checkbox and configure the off path deployment settings:

a.

b.

c.

From the Listening Interface field, select an adaptive security appliance interface. This is the interface on which the adaptive security appliance listens for the mapping requests.

In the Port field, enter a number between 1024 and 65535 as the TCP port on which the adaptive security appliance listens for the mapping requests. The port number must be 1024 or higher to avoid conflicts with other services on the device, such as Telnet or SSH. By default, the port number is

TCP 8060.

From the UC-IME Interface field, select an interface from the list. This is the interface that the adaptive security appliance uses to connect to the remote Cisco UCM.

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Note

In an off path deployment any existing adaptive security appliance that you have deployed in your environment are not capable of transmitting Cisco Intercompany Media Engine traffic.

Off-path signaling requires that outside addresses are translated (using NAT) to an inside IP address. The inside interface address can be used for this mapping service configuration. For the

Cisco Intercompany Media Engine Proxy, the adaptive security appliance creates dynamic mappings for external addresses to the internal IP address.

Step 10

In the Fallback area, configure the fallback timer for the Cisco Intercompany Media Engine by specifying the following settings:

a.

In the Fallback Sensitivity File field, enter the path to a file in flash memory that the adaptive security appliance uses for mid-call PSTN fallback. The file name that you enter must be the name of a file on disk that includes the .fbs file extension. Alternatively, click the Browse Flash button to locate and select the file from flash memory.

b.

c.

In the Call Quality Evaluation Interval field, enter a number between 10-600 (in milliseconds). This number controls the frequency at which the adaptive security appliance samples the RTP packets received from the Internet. The adaptive security appliance uses the data sample to determine if fallback to the PSTN is needed for a call. By default, the length is 100 milliseconds for the timer.

In the Notification Interval field, enter a number between 10-360 (in seconds). This number controls the amount of time that the adaptive security appliance waits before notifying Cisco UCM whether to fall back to PSTN. By default, the length is 20 seconds for this timer.

Note

When you change the fallback timer for the Cisco Intercompany Media Engine Proxy, ASDM automatically removes the proxy from SIP inspection and then reapplies SIP inspection when the proxy is re-enabled.

Step 11

Click Apply to save the configuration changes for the Cisco Intercompany Media Engine Proxy.

Configuring the Cisco UC-IMC Proxy by using the Unified Communications

Wizard

To configure the Cisco Intercompany Media Engine Proxy by using ASDM, choose Wizards > Unified

Communications Wizard from the menu. The Unified Communications Wizard opens. From the first page, select the Cisco Intercompany Media Engine Proxy option under the Business-to-Business section.

The wizard automatically creates the necessary TLS proxy, then guides you through creating the

Intercompany Media Engine proxy, importing and installing the required certificates, and finally enables the SIP inspection for the Intercompany Media Engine traffic automatically.

The wizard guides you through these steps to create the Cisco Intercompany Media Engine Proxy:

Step 1

Step 2

Step 3

Select the Intercompany Media Engine Proxy option.

Select the topology of the Cisco Intercompany Media Engine Proxy, namely whether the adaptive security appliance is an edge firewall with all Internet traffic flowing through it or whether the adaptive security appliance is off the path of the main Internet traffic (referred to as an off path deployment).

Specify private network settings such as the Cisco UCM IP addresses and the ticket settings.

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Step 4

Step 5

Step 6

Step 7

Specify the public network settings.

Specify the media termination address settings of Cisco UCM.

Configure the local-side certificate management, namely the certificates that are exchanged between the local Cisco Unified Communications Manager servers and the adaptive security appliance. The identity certificate that the wizard generates in this step needs to be installed on each Cisco Unified

Communications Manager (UCM) server in the cluster with the proxy and each identity certificate from the Cisco UCMs need to be installed on the adaptive security appliance. The certificates are used by the adaptive security appliance and the Cisco UCMs to authenticate each other, respectively, during TLS handshakes. The wizard only supports self-signed certificates for this step.

Configure the remote-side certificate management, namely the certificates that are exchanged between the remote server and the adaptive security appliance. In this step, the wizard generates a certificate signing request (CSR). After successfully generating the identity certificate request for the proxy, the wizard prompts you to save the file.

You must send the CSR text file to a certificate authority (CA), for example, by pasting the text file into the CSR enrollment page on the CA website. When the CA returns the Identity Certificate, you must install it on the adaptive security appliance. This certificate is presented to remote servers so that they can authenticate the adaptive security appliance as a trusted server.

Finally, this step of the wizard assists you in installing the root certificates of the CA from the remote servers so that the adaptive security appliance can determine that the remote servers are trusted.

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The wizard completes by displaying a summary of the configuration created for Cisco Intercompany

Media Engine. See the Unified Communications Wizard section in this documentation for more information.

This section describes how to certain options of the

show uc-ime

command to obtain troubleshooting information for the Cisco Intercompany Media Engine Proxy. See the

Cisco ASA 5500 Series Command

Reference

for detailed information about the syntax for these commands.

show uc-ime signaling-sessions

Displays the corresponding SIP signaling sessions stored by the Cisco Intercompany Media Engine

Proxy. Use this command to troubleshoot media or signaling failure. The command also displays the fallback parameters extracted from the SIP message headers, whether RTP monitoring is enabled or disabled, and whether SRTP keys are set.

Through the use of the Cisco Intercompany Media Engine Proxy, not only signaling but also media is secured for communication. It provides signaling encryption and SRTP/RTP conversion with SRTP enforced on the Internet side. The Cisco Intercompany Media Engine Proxy inserts itself into the media path by modifying the SIP signaling messages from Cisco UCMs.The Cisco Intercompany Media Engine

Proxy sits on the edge of the enterprise and inspects SIP signaling between SIP trunks created between enterprises. It terminates TLS signaling from the Internet and initiates TCP or TLS to the local Cisco

UCM. hostname# show uc-ime signaling-sessions

1 in use, 3 most used

inside 192.168.10.30:39608 outside 10.194.108.118:5070

Local Media (audio) conn: 10.194.108.119/29824 to 10.194.108.109/21558

Local SRTP key set : Remote SRTP key set

Remote Media (audio) conn: 192.168.10.51/19520 to 192.168.10.3/30930

Call-ID: [email protected]

FB Sensitivity: 3

Session ID: 2948-32325449-0@81a985c9-f3a1-55a0-3b19-96549a027259


47-35



SIP Trunk URI: 81a985c9-f3a1-55a0-3b19-9654@UCM-30;maddr=192.168.10.30

Codec-name: G722

Payload type: 9

Note

If calls are not going through the Cisco Intercompany Media Engine, you can also use the

show tls-proxy session

command to troubleshoot the success of the TLS handshake between the components in the Cisco Intercompany Media Engine system. See the


Command Reference

for information about this command.

show uc-ime signaling-sessions statistics

Displays statistical information about corresponding signaling sessions stored by Cisco Intercompany

Media Engine Proxy. Failure of signaling sessions in the Cisco Intercompany Media Engine can occur for different call-related reasons; such as failure of ticket verification or domain name verification, or offering RTP over the Internet. hostname# show uc-ime signaling-sessions statistics


15 terminated

Ticket integrity check failed: 2

Ticket decode failed: 1

Ticket epoch mismatch: 1

Ticket DID mismatch: 0

Ticket timestamp invalid: 4

Ticket domain check failed: 2

Ticket not found: 0

Route domain name check failed: 1

RTP over UC-IME: 2

Note

Call-related failures, for example, can be due to the service policy rule being reconfigured or the primary adaptive security appliance operating in failover mode. If a service policy rule for the Cisco

Intercompany Media Engine Proxy is removed (by using the

no service policy

command) and reconfigured, the first call trasversing the adaptive security appliance will fail. To resolve this issue, you must additionally enter the

clear connection

command and restart the adaptive security appliance. If the failure is due to failover, the connections from the primary adaptive security appliance are not synchronized to the standby adaptive security appliance.

show uc-ime media-sessions detail

Displays the details about all active media sessions (calls) stored for the Cisco Intercompany Media

Engine Proxy. Use this command to display output from successful calls. Additionally, use this command to troubleshoot problems with IP phone audio, such as one-way audio. If no calls are currently up, this output will be blank.

hostname(config)# show uc-ime media-sessions detail


Media-session: 10.194.108.109/21558 :: client ip 192.168.10.51/19520

Call ID: [email protected]

Session ID: 2948-32325449-0@81a985c9-f3a1-55a0-3b19-96549a027259

Lcl SRTP conn 10.194.108.109/21558 to 10.194.108.119/29824 tx_pkts 20203 rx_pkts 20200

refcnt 3 : created by Inspect SIP, passthrough not set

RTP monitoring is enabled

Failover_state : 0

Sum_all_packets : 20196

Codec_payload_format : 9

RTP_ptime_ms : 20

Max_RBLR_pct_x100 : 0

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Max_ITE_count_in_8_sec : 0

Max_BLS_ms : 0

Max_PDV_usec : 1000

Min_PDV_usec : 0

Mov_avg_PDV_usec : 109

Total_ITE_count : 0

Total_sec_count : 403

Concealed_sec_count : 0

Severely_concealed_sec_count : 0

Max_call_interval_ms : 118

Total_SequenceNumber_Resets : 0

Media-session: 192.168.10.3/30930 :: client ip 10.194.108.119/29824

Call ID: N/A

Lcl RTP conn 192.168.10.3/30930 to 192.168.10.51/19520 tx_pkts 20201 rx_pkts 20203

show uc-ime fallback-notification statistics

Displays statistics about the PSTN fallback notifications to the Cisco UMC. Even if a call is sent over

VoIP because the quality of the connection was good, the connection quality might worsen mid-call. To ensure an overall good experience for the end user, Cisco Intercompany Media Engine attempts to perform a mid-call fallback. Performing a mid-call fallback requires the adaptive security appliance to monitor the RTP packets coming from the Internet. If fallback is required, the adaptive security appliance sends a REFER message to Cisco UCM to tell it that it needs to fallback the call to PSTN.

Cisco Intercompany Media Engine uses a configurable hold-down timer to set the amount of time that adaptive security appliance waits before notifying Cisco UCM whether to fall back to PSTN.

hostname# show uc-ime fallback-notification statistics

UCM address: 172.23.32.37

Total Notifications Sent: 10

show uc-ime mapping-service-sessions

When the Cisco Intercompany Media Engine Proxy is configured for an off path deployment, displays mapping-service requests and replies between the proxy and the local Cisco UMC. A TCP port on the adaptive security appliance is configured to listen for mapping requests.

The port number must be 1024 or higher to avoid conflicts with other services on the device, such as

Telnet or SSH. By default, the port number is TCP 8060.

Hostname# show uc-b2blink mapping-service-sessions

Total active sessions: 2

Session client (IP:Port) Idle time

192.168.1.10:2001 0:01:01

192.168.1.20:3001 0:10:20

show uc-ime mapping-service-sessions statistics

Displays statistical information about the Cisco Intercompany Media Engine Proxy mapping service used in off path signaling.

Hostname# show uc-ime mapping-service-sessions statistics

Total active sessions: 2

Session client Total Responses Failed Pending Idle

(IP:Port) requests sent requests responses time

192.168.1.10:2001 10 9 1 0 0:01:01

192.168.1.20:3001 19 19 0 0 0:10:20

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Feature History for Cisco Intercompany Media Engine Proxy

Feature History for Cisco Intercompany Media Engine Proxy



Feature Name


Releases

8.3(1)


The Cisco Intercompany Media Engine Proxy was introduced.

The following pane was added to the ASDM:

Configuration > Firewall > Unified Communications >

UC-IME Proxy

The following wizard was added to ASDM, which allows you to configure the Unified Communication proxies

(including the Cisco Intercompany Media Engine Proxy):

Wizards > Unified Communications Wizard

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P

A R T

1 0

Configuring Connection Settings and QoS

C H A P T E R

48


This chapter describes how to configure connection settings for connections that go through the adaptive security appliance, or for management connections, that go to the adaptive security appliance.

Connection settings include:

•

Maximum connections (TCP and UDP connections, embryonic connections, per-client connections)

•

•

•

Connection timeouts

Dead connection detection

TCP sequence randomization

TCP normalization customization

•

•

•

TCP state bypass

Global timeouts


•

Information About Connection Settings, page 48-1

•

•

•

•

•

Licensing Requirements for Connection Settings, page 48-4



Configuring Connection Settings, page 48-5

Feature History for Connection Settings, page 48-11

Information About Connection Settings

This section describes why you might want to limit connections and includes the following topics:

•

TCP Intercept and Limiting Embryonic Connections, page 48-2

•

•

•

•

•

Disabling TCP Intercept for Management Packets for Clientless SSL Compatibility, page 48-2

Dead Connection Detection (DCD), page 48-2

TCP Sequence Randomization, page 48-2

TCP Normalization, page 48-3

TCP State Bypass, page 48-3


48-1 OL-20339-01

Chapter 48 Configuring Connection Settings


TCP Intercept and Limiting Embryonic Connections

Limiting the number of embryonic connections protects you from a DoS attack. The adaptive security appliance uses the per-client limits and the embryonic connection limit to trigger TCP Intercept, which protects inside systems from a DoS attack perpetrated by flooding an interface with TCP SYN packets.

An embryonic connection is a connection request that has not finished the necessary handshake between source and destination. TCP Intercept uses the SYN cookies algorithm to prevent TCP SYN-flooding attacks. A SYN-flooding attack consists of a series of SYN packets usually originating from spoofed IP addresses. The constant flood of SYN packets keeps the server SYN queue full, which prevents it from servicing connection requests. When the embryonic connection threshold of a connection is crossed, the adaptive security appliance acts as a proxy for the server and generates a SYN-ACK response to the client SYN request. When the adaptive security appliance receives an ACK back from the client, it can then authenticate the client and allow the connection to the server.

To view TCP Intercept statistics, including the top 10 servers under attack, see

Chapter 51, “Configuring

Threat Detection.”

Disabling TCP Intercept for Management Packets for Clientless SSL

Compatibility

By default, TCP management connections have TCP Intercept always enabled. When TCP Intercept is enabled, it intercepts the 3-way TCP connection establishment handshake packets and thus deprives the adaptive security appliance from processing the packets for clientless SSL. Clientless SSL requires the ability to process the 3-way handshake packets to provide selective ACK and other TCP options for clientless SSL connections. To disable TCP Intercept for management traffic, you can set the embryonic connection limit; only after the embryonic connection limit is reached is TCP Intercept enabled.

Dead Connection Detection (DCD)

DCD detects a dead connection and allows it to expire, without expiring connections that can still handle traffic. You configure DCD when you want idle, but valid connections to persist.

When you enable DCD, idle timeout behavior changes. With idle timeout, DCD probes are sent to each of the two end-hosts to determine the validity of the connection. If an end-host fails to respond after probes are sent at the configured intervals, the connection is freed, and reset values, if configured, are sent to each of the end-hosts. If both end-hosts respond that the connection is valid, the activity timeout is updated to the current time and the idle timeout is rescheduled accordingly.

Enabling DCD changes the behavior of idle-timeout handling in the TCP normalizer. DCD probing resets the idle timeout on the connections seen in the

show conn

command. To determine when a connection that has exceeded the configured timeout value in the timeout command but is kept alive due to DCD probing, the

show service-policy

command includes counters to show the amount of activity from DCD.

TCP Sequence Randomization

Each TCP connection has two ISNs: one generated by the client and one generated by the server. The adaptive security appliance randomizes the ISN of the TCP SYN passing in both the inbound and outbound directions.

48-2


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Randomizing the ISN of the protected host prevents an attacker from predecting the next ISN for a new connection and potentially hijacking the new session.

TCP initial sequence number randomization can be disabled if required. For example:

•

If another in-line firewall is also randomizing the initial sequence numbers, there is no need for both firewalls to be performing this action, even though this action does not affect the traffic.

•

•

If you use eBGP multi-hop through the adaptive security appliance, and the eBGP peers are using

MD5. Randomization breaks the MD5 checksum.

You use a WAAS device that requires the adaptive security appliance not to randomize the sequence numbers of connections.

TCP Normalization

The TCP normalization feature identifies abnormal packets that the adaptive security appliance can act on when they are detected; for example, the adaptive security appliance can allow, drop, or clear the packets. TCP normalization helps protect the adaptive security appliance from attacks. TCP normalization is always enabled, but you can customize how some features behave.

The TCP normalizer includes non-configurable actions and configurable actions. Typically, non-configurable actions that drop or clear connections apply to packets that are always bad.

Configurable actions (as detailed in

“Customizing the TCP Normalizer with a TCP Map” section on page 48-6

) might need to be customized depending on your network needs.

See the following guidelines for TCP normalization:

•

The normalizer does not protect from SYN floods. The adaptive security appliance includes SYN flood protection in other ways.

•

The normalizer always sees the SYN packet as the first packet in a flow unless the adaptive security appliance is in loose mode due to failover.

TCP State Bypass

By default, all traffic that goes through the adaptive security appliance is inspected using the Adaptive

Security Algorithm and is either allowed through or dropped based on the security policy. The adaptive security appliance maximizes the firewall performance by checking the state of each packet (is this a new connection or an established connection?) and assigning it to either the session management path (a new connection SYN packet), the fast path (an established connection), or the control plane path (advanced

inspection). See the “Stateful Inspection Overview” section on page 1-18 for more detailed information

about the stateful firewall.

TCP packets that match existing connections in the fast path can pass through the adaptive security appliance without rechecking every aspect of the security policy. This feature maximizes performance.

However, the method of establishing the session in the fast path using the SYN packet, and the checks that occur in the fast path (such as TCP sequence number), can stand in the way of asymmetrical routing solutions: both the outbound and inbound flow of a connection must pass through the same adaptive security appliance.

For example, a new connection goes to adaptive security appliance 1. The SYN packet goes through the session management path, and an entry for the connection is added to the fast path table. If subsequent packets of this connection go through adaptive security appliance 1, then the packets will match the entry in the fast path, and are passed through. But if subsequent packets go to adaptive security appliance 2, where there was not a SYN packet that went through the session management path, then there is no entry

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48-3


Licensing Requirements for Connection Settings

in the fast path for the connection, and the packets are dropped.

Figure 48-1

shows an asymmetric routing example where the outbound traffic goes through a different adaptive security appliance than the inbound traffic:

Figure 48-1 Asymmetric Routing

ISP A ISP B

Security appliance 1

Security appliance 2

Outbound?Traffic

Return?Traffic

Inside network

If you have asymmetric routing configured on upstream routers, and traffic alternates between two adaptive security appliances, then you can configure TCP state bypass for specific traffic. TCP state bypass alters the way sessions are established in the fast path and disables the fast path checks. This feature treats TCP traffic much as it treats a UDP connection: when a non-SYN packet matching the specified networks enters the adaptive security appliance, and there is not an fast path entry, then the packet goes through the session management path to establish the connection in the fast path. Once in the fast path, the traffic bypasses the fast path checks.

Licensing Requirements for Connection Settings

Model

All models


Base License.


This section includes the following guidelines and limitations:

•

TCP State Bypass Guidelines and Limitations, page 48-5

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TCP State Bypass Guidelines and Limitations






Failover is supported.

Unsupported Features

The following features are not supported when you use TCP state bypass:

•

Application inspection—Application inspection requires both inbound and outbound traffic to go through the same adaptive security appliance, so application inspection is not supported with TCP state bypass.

•

•

•

•

AAA authenticated sessions—When a user authenticates with one adaptive security appliance, traffic returning via the other adaptive security appliance will be denied because the user did not authenticate with that adaptive security appliance.

TCP Intercept, maximum embryonic connection limit, TCP sequence number randomization—The adaptive security appliance does not keep track of the state of the connection, so these features are not applied.

TCP normalization—The TCP normalizer is disabled.

SSM and SSC functionality—You cannot use TCP state bypass and any application running on an

SSM or SSC, such as IPS or CSC.

NAT Guidelines

Because the translation session is established separately for each adaptive security appliance, be sure to configure static NAT on both adaptive security appliances for TCP state bypass traffic; if you use dynamic NAT, the address chosen for the session on adaptive security appliance 1 will differ from the address chosen for the session on adaptive security appliance 2.



TCP state bypass is disabled by default.



•

•

Customizing the TCP Normalizer with a TCP Map, page 48-6

Configuring Connection Settings, page 48-8

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48-5



•

Configuring Global Timeouts, page 48-9

Task Flow For Configuring Configuration Settings (Except Global Timeouts)

Step 1

Step 2

Step 3

For TCP normalization customization, create a TCP map according to the

“Customizing the TCP

Normalizer with a TCP Map” section on page 48-6 .

For all connection settings except for global timeouts, configure a service policy according to

Chapter 29, “Configuring a Service Policy.”

Configure connection settings according to the

“Configuring Connection Settings” section on page 48-8

.

Customizing the TCP Normalizer with a TCP Map

To customize the TCP normalizer, first define the settings using a TCP map.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Choose the

Configuration > Firewall > Objects > TCP Maps

pane, and click

Add

.

The Add TCP Map dialog box appears.

In the TCP Map Name field, enter a name.

In the Queue Limit field, enter the maximum number of out-of-order packets, between 0 and 250 packets.

The Queue Limit sets the maximum number of out-of-order packets that can be buffered and put in order for a TCP connection. The default is 0, which means this setting is disabled and the default system queue limit is used depending on the type of traffic:

•

Connections for application inspection, IPS, and TCP check-retransmission have a queue limit of 3 packets. If the adaptive security appliance receives a TCP packet with a different window size, then the queue limit is dynamically changed to match the advertised setting.

•

For other TCP connections, out-of-order packets are passed through untouched.

If you set the Queue Limit command to be 1 or above, then the number of out-of-order packets allowed for all TCP traffic matches this setting. For application inspection, IPS, and TCP check-retransmission traffic, any advertised settings are ignored. For other TCP traffic, out-of-order packets are now buffered and put in order instead of passed through untouched.

In the Timeout field, set the maximum amount of time that out-of-order packets can remain in the buffer, between 1 and 20 seconds.

If they are not put in order and passed on within the timeout period, then they are dropped. The default is 4 seconds. You cannot change the timeout for any traffic if the Queue Limit is set to 0; you need to set the limit to be 1 or above for the Timeout to take effect.

In the Reserved Bits area, click

Clear and allow

,

Allow only

, or

Drop

.

Allow only allows packets with the reserved bits in the TCP header.

Clear and allow clears the reserved bits in the TCP header and allows the packet.

Drop drops the packet with the reserved bits in the TCP header.

Check any of the following options:


48-6 OL-20339-01



•

•

•

•

•

•

•

•

•

•

•

Clear urgent flag—Clears the URG flag through the adaptive security appliance. The URG flag is used to indicate that the packet contains information that is of higher priority than other data within the stream. The TCP RFC is vague about the exact interpretation of the URG flag, therefore end systems handle urgent offsets in different ways, which may make the end system vulnerable to attacks.

Drop connection on window variation—Drops a connection that has changed its window size unexpectedly. The window size mechanism allows TCP to advertise a large window and to subsequently advertise a much smaller window without having accepted too much data. From the

TCP specification, “shrinking the window” is strongly discouraged. When this condition is detected, the connection can be dropped.

Drop packets that exceed maximum segment size—Drops packets that exceed MSS set by peer.

Check if transmitted data is the same as original—Enables the retransmit data checks.

Drop packets which have past-window sequence—Drops packets that have past-window sequence numbers, namely the sequence number of a received TCP packet is greater than the right edge of the

TCP receiving window. If you do not check this option, then the Queue Limit must be set to 0

(disabled).

Drop SYN Packets with data—Drops SYN packets with data.

Enable TTL Evasion Protection—Enables the TTL evasion protection offered by the adaptive security appliance. Do not enable this option if you want to prevent attacks that attempt to evade security policy.

For example, an attacker can send a packet that passes policy with a very short TTL. When the TTL goes to zero, a router between the adaptive security appliance and the endpoint drops the packet. It is at this point that the attacker can send a malicious packet with a long TTL that appears to the adaptive security appliance to be a retransmission and is passed. To the endpoint host, however, it is the first packet that has been received by the attacker. In this case, an attacker is able to succeed without security preventing the attack.

Verify TCP Checksum—Enables checksum verification.

Drop SYNACK Packets with data—Drops TCP SYNACK packets that contain data.

Drop packets with invalid ACK—Drops packets with an invalid ACK. You might see invalid ACKs in the following instances:

–

–

In the TCP connection SYN-ACK-received status, if the ACK number of a received TCP packet is not exactly same as the sequence number of the next TCP packet sending out, it is an invalid

ACK.

Whenever the ACK number of a received TCP packet is greater than the sequence number of the next TCP packet sending out, it is an invalid ACK.

Note

TCP packets with an invalid ACK are automatically allowed for WAAS connections.

Step 7

To set TCP options, check any of the following options:

•

•

•

Clear Selective Ack—Sets whether the selective-ack TCP option is allowed or cleared.

Clear TCP Timestamp—Sets whether the TCP timestamp option is allowed or cleared.

•

Clear Window Scale—Sets whether the window scale timestamp option is allowed or cleared.

Range—Sets the valid TCP options ranges, which should fall within 6-7 and 9-255. The lower bound should be less than or equal to the upper bound. Choose

Allow

or

Drop

for each range.

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Step 8

Click

OK

.


To set connection settings, perform the following steps.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Configure a service policy on the Configuration > Firewall > Service Policy Rules pane according to


You can configure connection limits as part of a new service policy rule, or you can edit an existing service policy.

On the Rule Actions dialog box, click the

Connection Settings

tab.

To set maximum connections, configure the following values in the Maximum Connections area:

•

TCP & UDP Connections—Specifies the maximum number of simultaneous TCP and UDP connections for all clients in the traffic class, up to 65,536. The default is 0 for both protocols, which means the maximum possible connections are allowed.

•

•

Embryonic Connections—Specifies the maximum number of embryonic connections per host up to

65,536. An embryonic connection is a connection request that has not finished the necessary handshake between source and destination. This limit enables the TCP Intercept feature. The default is

0

, which means the maximum embryonic connections. TCP Intercept protects inside systems from a DoS attack perpetrated by flooding an interface with TCP SYN packets. When the embryonic limit has been surpassed, the TCP intercept feature intercepts TCP SYN packets from clients to servers on a higher security level. SYN cookies are used during the validation process and help to minimize the amount of valid traffic being dropped. Thus, connection attempts from unreachable hosts will never reach the server.

Per Client Connections—Specifies the maximum number of simultaneous TCP and UDP connections for each client. When a new connection is attempted by a client that already has opened the maximum per-client number of connections, the adaptive security appliance rejects the connection and drops the packet.

•

Per Client Embryonic Connections—Specifies the maximum number of simultaneous TCP embryonic connections for each client. When a new TCP connection is requested by a client that already has the maximum per-client number of embryonic connections open through the adaptive security appliance, the adaptive security appliance proxies the request to the TCP Intercept feature, which prevents the connection.

To configure connection timeouts, configure the following values in the TCP Timeout area:

•

•

•

Connection Timeout—Specifies the idle time until a connection slot (of

any

protocol, not just TCP) is freed. Enter 0:0:0 to disable timeout for the connection. This duration must be at least 5 minutes.

The default is 1 hour.

Send reset to TCP endpoints before timeout—Specifies that the adaptive security appliance should send a TCP reset message to the endpoints of the connection before freeing the connection slot.

Embryonic Connection Timeout—Specifies the idle time until an embryonic connection slot is freed. Enter 0:0:0 to disable timeout for the connection. The default is 30 seconds.

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Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

•

Half Closed Connection Timeout—Specifies the idle time until a half closed connection slot is freed.

Enter 0:0:0 to disable timeout for the connection. This duration must be at least 5 minutes. The default is 10 minutes.

To disable randomized sequence numbers, uncheck

Randomize Sequence Number

.

TCP initial sequence number randomization can be disabled if another in-line firewall is also randomizing the initial sequence numbers, because there is no need for both firewalls to be performing this action. However, leaving ISN randomization enabled on both firewalls does not affect the traffic.

Each TCP connection has two ISNs: one generated by the client and one generated by the server. The security appliance randomizes the ISN of the TCP SYN passing in the outbound direction. If the connection is between two interfaces with the same security level, then the ISN will be randomized in the SYN in both directions.

Randomizing the ISN of the protected host prevents an attacker from predecting the next ISN for a new connection and potentially hijacking the new session.

To configure TCP normalization, check

Use TCP Map

. Choose an existing TCP map from the drop-down list (if available), or add a new one by clicking

New

.

The Add TCP Map dialog box appears. See the

“Customizing the TCP Normalizer with a TCP Map” section on page 48-6 .

Click

OK

.

To set the time to live, check

Decrement time to live for a connection

.

To enable TCP state bypass, in the Advanced Options area, check


.

Click

OK

or

Finish

.

Configuring Global Timeouts

The Configuration > Properties > Timeouts pane lets you set the timeout durations for use with the adaptive security appliance. All durations are displayed in the format hh:mm:ss. It sets the idle time for the connection and translation slots of various protocols. If the slot has not been used for the idle time specified, the resource is returned to the free pool. TCP connection slots are freed approximately 60 seconds after a normal connection close sequence.

Fields

In all cases, except for Authentication absolute and Authentication inactivity, unchecking the check boxes means there is no timeout value. For those two cases, clearing the check box means to reauthenticate on every new connection.

•

Connection—Modifies the idle time until a connection slot is freed. Enter 0:0:0 to disable timeout for the connection. This duration must be at least 5 minutes. The default is 1 hour.

•

•

•

•

Half-closed—Modifies the idle time until a TCP half-closed connection closes. The minimum is 5 minutes. The default is 10 minutes. Enter 0:0:0 to disable timeout for a half-closed connection.

UDP—Modifies the idle time until a UDP protocol connection closes. This duration must be at least

1 minute. The default is 2 minutes. Enter 0:0:0 to disable timeout.

ICMP—Modifies the idle time after which general ICMP states are closed.

H.323—Modifies the idle time until an H.323 media connection closes. The default is 5 minutes.

Enter 0:0:0 to disable timeout.

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48-9



•

•

•

•

•

•

•

•

•

•

H.225—Modifies the idle time until an H.225 signaling connection closes. The H.225 default timeout is 1 hour (01:00:00). Setting the value of 00:00:00 means never close this connection. To close this connection immediately after all calls are cleared, a value of 1 second (00:00:01) is recommended.

MGCP—Modifies the timeout value for MGCP which represents the idle time after which MGCP media ports are closed. The MGCP default timeout is 5 minutes (00:05:00). Enter 0:0:0 to disable timeout.

MGCP PAT—Modifies the idle time after which an MGCP PAT translation is removed. The default is 5 minutes (00:05:00). The minimum time is 30 seconds. Uncheck the check box to return to the default value.

SUNRPC—Modifies the idle time until a SunRPC slot is freed. This duration must be at least 1 minute. The default is 10 minutes. Enter 0:0:0 to disable timeout.

SIP—Modifies the idle time until an SIP signalling port connection closes. This duration must be at least 5 minutes. The default is 30 minutes.

SIP Media—Modifies the idle time until an SIP media port connection closes. This duration must be at least 1 minute. The default is 2 minutes.

SIP Provisional Media—Modifies the timeout value for SIP provisional media connections, between

0:1:0 and 1193:0:0. The default is 2 minutes.

SIP Invite—Modifies the idle time after which pinholes for PROVISIONAL responses and media xlates will be closed. The minimum value is 0:1:0, the maximum value is 0:30:0. The default value is 0:03:00.

SIP Disconnect—Modifies the idle time after which SIP session is deleted if the 200 OK is not received for a CANCEL or a BYE message. The minimum value is 0:0:1, the maximum value is

0:10:0. The default value is 0:02:00.

Authentication absolute—Modifies the duration until the authentication cache times out and you have to reauthenticate a new connection. This duration must be shorter than the Translation Slot value. The system waits until you start a new connection to prompt you again. Enter 0:0:0 to disable caching and reauthenticate on every new connection.

Note

Do not set this value to 0:0:0 if passive FTP is used on the connections.

Note

When Authentication Absolute = 0, HTTPS authentication may not work. If a browser initiates multiple TCP connections to load a web page after HTTPS authentication, the first connection is permitted through, but subsequent connections trigger authentication. As a result, users are continuously presented with an authentication page, even after successful authentication. To work around this, set the authentication absolute timeout to 1 second. This workaround opens a

1-second window of opportunity that might allow non-authenticated users to go through the firewall if they are coming from the same source IP address.

•

•

Authentication inactivity—Modifies the idle time until the authentication cache times out and users have to reauthenticate a new connection. This duration must be shorter than the Translation Slot value.

Translation Slot—Modifies the idle time until a translation slot is freed. This duration must be at least 1 minute. The default is 3 hours. Enter 0:0:0 to disable timeout.

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Feature History for Connection Settings


Table 48-1


Table 48-1 Feature History for Connection Settings

Feature Name

TCP state bypass

Platform

Releases

8.2(1)

Connection timeout for all protocols 8.2(2)


This feature was introduced. The following command was introduced:

set connection advanced-options tcp-state-bypass

.

The idle timeout was changed to apply to all protocols, not just TCP.


Firewall > Service Policies > Rule Actions > Connection

Settings.

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C H A P T E R

49

Configuring QoS

Have you ever participated in a long-distance phone call that involved a satellite connection? The conversation might be interrupted with brief, but perceptible, gaps at odd intervals. Those gaps are the time, called the latency, between the arrival of packets being transmitted over the network. Some network traffic, such as voice and video, cannot tolerate long latency times. Quality of service (QoS) is a feature that lets you give priority to critical traffic, prevent bandwidth hogging, and manage network bottlenecks to prevent packet drops.

This chapter describes how to apply QoS policies and includes the following sections:

•

•

Information About QoS, page 49-1

Configuring QoS, page 49-5

Information About QoS

You should consider that in an ever-changing network environment, QoS is not a one-time deployment, but an ongoing, essential part of network design.

Note

QoS is only available in single context mode.

This section describes the QoS features supported by the adaptive security appliance and includes the following topics:

•

•

•

•

•

•

Supported QoS Features, page 49-2

What is a Token Bucket?, page 49-2

Information About Policing, page 49-3

Information About Priority Queueing, page 49-3

Information About Traffic Shaping, page 49-4

DSCP and DiffServ Preservation, page 49-5


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Chapter 49 Configuring QoS


Supported QoS Features

The adaptive security appliance supports the following QoS features:

•

Policing—To prevent individual flows from hogging the network bandwidth, you can limit the maximum bandwidth used per flow. See the

“Information About Policing” section on page 49-3


•

•

Priority queuing—For critical traffic that cannot tolerate latency, such as Voice over IP (VoIP), you can identify traffic for Low Latency Queuing (LLQ) so that it is always transmitted ahead of other

traffic. See the “Information About Priority Queueing” section on page 49-3 for more information.

Traffic shaping—If you have a device that transmits packets at a high speed, such as a adaptive security appliance with Fast Ethernet, and it is connected to a low speed device such as a cable modem, then the cable modem is a bottleneck at which packets are frequently dropped. To manage networks with differing line speeds, you can configure the adaptive security appliance to transmit packets at a fixed slower rate. See the

“Information About Traffic Shaping” section on page 49-4 for

more information.

What is a Token Bucket?

A token bucket is used to manage a device that regulates the data in a flow. For example, the regulator might be a traffic policer or a traffic shaper. A token bucket itself has no discard or priority policy.

Rather, a token bucket discards tokens and leaves to the flow the problem of managing its transmission queue if the flow overdrives the regulator.

A token bucket is a formal definition of a rate of transfer. It has three components: a burst size, an average rate, and a time interval. Although the average rate is generally represented as bits per second, any two values may be derived from the third by the relation shown as follows: average rate = burst size / time interval

Here are some definitions of these terms:

•

•

Average rate—Also called the committed information rate (CIR), it specifies how much data can be sent or forwarded per unit time on average.

Burst size—Also called the Committed Burst (Bc) size, it specifies in bits or bytes per burst how much traffic can be sent within a given unit of time to not create scheduling concerns. (For traffic shaping, it specifies bits per burst; for policing, it specifies bytes per burst.)

•

Time interval—Also called the measurement interval, it specifies the time quantum in seconds per burst.

In the token bucket metaphor, tokens are put into the bucket at a certain rate. The bucket itself has a specified capacity. If the bucket fills to capacity, newly arriving tokens are discarded. Each token is permission for the source to send a certain number of bits into the network. To send a packet, the regulator must remove from the bucket a number of tokens equal in representation to the packet size.

If not enough tokens are in the bucket to send a packet, the packet either waits until the bucket has enough tokens (in the case of traffic shaping) or the packet is discarded or marked down (in the case of policing). If the bucket is already full of tokens, incoming tokens overflow and are not available to future packets. Thus, at any time, the largest burst a source can send into the network is roughly proportional to the size of the bucket.

Note that the token bucket mechanism used for traffic shaping has both a token bucket and a data buffer, or queue; if it did not have a data buffer, it would be a policer. For traffic shaping, packets that arrive that cannot be sent immediately are delayed in the data buffer.

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For traffic shaping, a token bucket permits burstiness but bounds it. It guarantees that the burstiness is bounded so that the flow will never send faster than the token bucket capacity, divided by the time interval, plus the established rate at which tokens are placed in the token bucket. See the following formula:

(token bucket capacity in bits / time interval in seconds) + established rate in bps = maximum flow speed in bps

This method of bounding burstiness also guarantees that the long-term transmission rate will not exceed the established rate at which tokens are placed in the bucket.

Information About Policing

Policing is a way of ensuring that no traffic exceeds the maximum rate (in bits/second) that you configure, thus ensuring that no one traffic flow or class can take over the entire resource. When traffic exceeds the maximum rate, the adaptive security appliance drops the excess traffic. Policing also sets the largest single burst of traffic allowed.

Information About Priority Queueing

LLQ priority queueing lets you prioritize certain traffic flows (such as latency-sensitive traffic like voice and video) ahead of other traffic.

The adaptive security appliance supports two types of priority queueing:

•

Standard priority queueing—Standard priority queueing uses an LLQ priority queue on an interface

(see the

“Creating the Standard Priority Queue for an Interface” section on page 49-5

), while all other traffic goes into the “best effort” queue. Because queues are not of infinite size, they can fill and overflow. When a queue is full, any additional packets cannot get into the queue and are dropped. This is called

tail drop

. To avoid having the queue fill up, you can increase the queue buffer size. You can also fine-tune the maximum number of packets allowed into the transmit queue. These options let you control the latency and robustness of the priority queuing. Packets in the LLQ queue are always transmitted before packets in the best effort queue.

•

Hierarchical priority queueing—Hierarchical priority queueing is used on interfaces on which you enable a traffic shaping queue. A subset of the shaped traffic can be prioritized. The standard priority queue is not used. See the following guidelines about hierarchical priority queueing:

–

Priority packets are always queued at the head of the shape queue so they are always transmitted ahead of other non-priority queued packets.

–

–

–

Priority packets are never dropped from the shape queue unless the sustained rate of priority traffic exceeds the shape rate.

For IPSec-encrypted packets, you can only match traffic based on the DSCP or precedence setting.

IPSec-over-TCP is not supported for priority traffic classification.

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49-3



Information About Traffic Shaping

Traffic shaping is used to match device and link speeds, thereby controlling packet loss, variable delay, and link saturation, which can cause jitter and delay.

Note

Traffic shaping is not supported on the ASA 5580.

•

•

•

•

•

Traffic shaping must be applied to all outgoing traffic on a physical interface or in the case of the

ASA 5505, on a VLAN. You cannot configure traffic shaping for specific types of traffic.

Traffic shaping is implemented when packets are ready to be transmitted on an interface, so the rate calculation is performed based on the actual size of a packet to be transmitted, including all the possible overhead such as the IPSec header and L2 header.

The shaped traffic includes both through-the-box and from-the-box traffic.

The shape rate calculation is based on the standard token bucket algorithm. The token bucket size is twice the Burst Size value. See the

“What is a Token Bucket?” section on page 49-2 .

When bursty traffic exceeds the specified shape rate, packets are queued and transmitted later.

Following are some characteristics regarding the shape queue (for information about hierarchical priority queueing, see the

“Information About Priority Queueing” section on page 49-3

):

–

The queue size is calculated based on the shape rate. The queue can hold the equivalent of

200-milliseconds worth of shape rate traffic, assuming a 1500-byte packet. The minimum queue size is 64.

–

–

When the queue limit is reached, packets are tail-dropped.

Certain critical keep-alive packets such as OSPF Hello packets are never dropped.

–

The time interval is derived by

time_interval

=

burst_size

/

average_rate

. The larger the time interval is, the burstier the shaped traffic might be, and the longer the link might be idle. The effect can be best understood using the following exaggerated example:

Average Rate = 1000000

Burst Size = 1000000

In the above example, the time interval is 1 second, which means, 1 Mbps of traffic can be bursted out within the first 10 milliseconds of the 1-second interval on a 100 Mbps FE link and leave the remaining 990 milliseconds idle without being able to send any packets until the next time interval. So if there is delay-sensitive traffic such as voice traffic, the Burst Size should be reduced compared to the average rate so the time interval is reduced.

How QoS Features Interact

You can configure each of the QoS features alone if desired for the adaptive security appliance. Often, though, you configure multiple QoS features on the adaptive security appliance so you can prioritize some traffic, for example, and prevent other traffic from causing bandwidth problems.

See the following supported feature combinations per interface:

•

•

Standard priority queuing (for specific traffic) + Policing (for the rest of the traffic).

You cannot configure priority queueing and policing for the same set of traffic.

Traffic shaping (for all traffic on an interface) + Hierarchical priority queueing (for a subset of traffic).

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Configuring QoS

You cannot configure traffic shaping and standard priority queueing for the same interface; only hierarchical priority queueing is allowed. For example, if you configure standard priority queueing for the global policy, and then configure traffic shaping for a specific interface, the feature you configured last is rejected because the global policy overlaps the interface policy.

Typically, if you enable traffic shaping, you do not also enable policing for the same traffic, although the adaptive security appliance does not restrict you from configuring this.

DSCP and DiffServ Preservation

•

•

•

DSCP markings are preserved on all traffic passing through the adaptive security appliance.

The adaptive security appliance does not locally mark/remark any classified traffic, but it honors the

Expedited Forwarding (EF) DSCP bits of every packet to determine if it requires “priority” handling and will direct those packets to the LLQ.

DiffServ marking is preserved on packets when they traverse the service provider backbone so that

QoS can be applied in transit (QoS tunnel pre-classification).

Configuring QoS


•

•

•

Creating the Standard Priority Queue for an Interface, page 49-5

Creating a Policy for Standard Priority Queueing and/or Policing, page 49-7

Creating a Policy for Traffic Shaping and Hierarchical Priority Queueing, page 49-8

Creating the Standard Priority Queue for an Interface

If you enable standard priority queueing for traffic on a physical interface, then you need to also create the priority queue on each interface. Each physical interface uses two queues: one for priority traffic, and the other for all other traffic. For the other traffic, you can optionally configure policing.

Note

The standard priority queue is not required for hierarchical priority queueing with traffic shaping; see the

“Information About Priority Queueing” section on page 49-3 for more information.

You cannot create a priority queue for a Ten Gigabit Ethernet interface; priority queuing is not necessary for an interface with high bandwidth.


•

•

Determining the Queue and TX Ring Limits, page 49-6

Configuring the Priority Queue, page 49-7

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Configuring QoS

Determining the Queue and TX Ring Limits

To determine the priority queue and TX ring limits, use the worksheets below.

Table 49-1 shows how to calculate the priority queue size. Because queues are not of infinite size, they

can fill and overflow. When a queue is full, any additional packets cannot get into the queue and are dropped (called

tail drop

). To avoid having the queue fill up, you can adjust the queue buffer size according to the

“Configuring the Priority Queue” section on page 49-7 .

Table 49-1 Queue Limit Worksheet

Step 1

__________

Outbound bandwidth

(Mbps or Kbps)

1

Mbps

x

125

=

__________

# of bytes/ms

Kbps

x

.125

=

__________

# of bytes/ms

Step 2

___________

# of bytes/ms from Step 1

÷

__________

Average packet size (bytes)

2

x

__________

Delay (ms)

3

=

__________

Queue limit

(# of packets)

1.

For example, DSL might have an uplink speed of 768 Kbps. Check with your provider.

2.

Determine this value from a codec or sampling size. For example, for VoIP over VPN, you might use 160 bytes. We recommend 256 bytes if you do not know what size to use.

3.

The delay depends on your application. For example, the recommended maximum delay for VoIP is 200 ms. We recommend 500 ms if you do not know what delay to use.

Table 49-2 shows how to calculate the TX ring limit. This limit determines the maximum number of

packets allowed into the Ethernet transmit driver before the driver pushes back to the queues on the interface to let them buffer packets until the congestion clears. This setting guarantees that the hardware-based transmit ring imposes a limited amount of extra latency for a high-priority packet.

Table 49-2 TX Ring Limit Worksheet

Step 1

__________

Outbound bandwidth

(Mbps or Kbps)

1

Mbps

x

125

=

__________

# of bytes/ms

Kbps

x

0.125

=

__________

# of bytes/ms

Step 2

___________

# of bytes/ms from Step 1

÷

__________

Maximum packet size (bytes)

2

x

__________

Delay (ms)

3

=

__________

TX ring limit

(# of packets)

1.

For example, DSL might have an uplink speed of 768 Kbps.Check with your provider.

2.

Typically, the maximum size is 1538 bytes, or 1542 bytes for tagged Ethernet. If you allow jumbo frames (if supported for your platform), then the packet size might be larger.

3.

The delay depends on your application. For example, to control jitter for VoIP, you should use 20 ms.


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Configuring QoS

Configuring the Priority Queue

To create the priority queue, perform the following steps.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Go to Configuration > Device Management > Advanced > Priority Queue, and click

Add

.

The Add Priority Queue dialog box displays.

From the Interface drop-down list, choose the physical interface name on which you want to enable the priority queue, or for the ASA 5505, the VLAN interface name.

To change the size of the priority queues, in the Queue Limit field, enter the number of average, 256-byte packets that the specified interface can transmit in a 500-ms interval.

A packet that stays more than 500 ms in a network node might trigger a timeout in the end-to-end application. Such a packet can be discarded in each network node.

Because queues are not of infinite size, they can fill and overflow. When a queue is full, any additional packets cannot get into the queue and are dropped (called

tail drop

). To avoid having the queue fill up, you can use this option to increase the queue buffer size.

The upper limit of the range of values for this option is determined dynamically at run time. The key determinants are the memory needed to support the queues and the memory available on the device.

The Queue Limit that you specify affects both the higher priority low-latency queue and the best effort queue.

To specify the depth of the priority queues, in the Transmission Ring Limit field, enter the number of maximum 1550-byte packets that the specified interface can transmit in a 10-ms interval.

This setting guarantees that the hardware-based transmit ring imposes no more than 10-ms of extra latency for a high-priority packet.

This option sets the maximum number of low-latency or normal priority packets allowed into the

Ethernet transmit driver before the driver pushes back to the queues on the interface to let them buffer packets until the congestion clears.

The upper limit of the range of values is determined dynamically at run time. The key determinants are the memory needed to support the queues and the memory available on the device.

The Transmission Ring Limit that you specify affects both the higher priority low-latency queue and the best-effort queue.

Creating a Policy for Standard Priority Queueing and/or Policing

You can configure standard priority queueing and policing for different class maps within the same

policy map. See the “How QoS Features Interact” section on page 49-4

for information about valid QoS configurations.

To create a policy map, perform the following steps.

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49-7


Configuring QoS

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

To configure priority queueing, configure a service policy rule in the Configuration > Firewall > Service

Policy Rules pane according to


You can configure QoS as part of a new service policy rule, or you can edit an existing service policy.

For priority traffic, identify only latency-sensitive traffic. You can match traffic based on many characteristics, including access lists, tunnel groups, DSCP, precedence, and more. You cannot use the

class-default

class map for priority traffic. You cannot configure priority queueing for the global policy if you also enable traffic shaping on any interfaces.

In the Rule Actions dialog box, click the

QoS

tab.

Click

Enable priority for this flow

.

If this service policy rule is for an individual interface, ASDM automatically creates the priority queue for the interface (Configuration > Properties > Priority Queue; for more information, see the

“Creating the Standard Priority Queue for an Interface” section on page 49-5

). If this rule is for the global policy, then you need to manually add the priority queue to one or more interfaces

before

you configure the service policy rule.

Click

Finish

. The service policy rule is added to the rule table.

To configure policing, configure a service policy rule for the same interface in the Configuration >

Firewall > Service Policy Rules pane according to


For policing traffic, you can choose to police all traffic that you are not prioritizing, or you can limit the traffic to certain types.


QoS

tab.

Click

Enable policing

, then check the

Input policing

or

Output policing

(or both) check boxes to enable the specified type of traffic policing. For each type of traffic policing, configure the following fields:

•

Committed Rate—The rate limit for this traffic flow; this is a value in the range 8000-2000000000, specifying the maximum speed (bits per second) allowed.

•

•

Conform Action—The action to take when the rate is less than the conform-burst value. Values are transmit or drop.

Exceed Action—Take this action when the rate is between the conform-rate value and the conform-burst value. Values are transmit or drop.

•

Burst Rate—A value in the range 1000-512000000, specifying the maximum number of instantaneous bytes allowed in a sustained burst before throttling to the conforming rate value.

Click

Finish


Click

Apply

to send the configuration to the device.

Creating a Policy for Traffic Shaping and Hierarchical Priority Queueing

You can configure traffic shaping for all traffic on an interface, and optionally hierarchical priority queueing for a subset of latency-sensitive traffic. See the

“How QoS Features Interact” section on page 49-4 for information about valid QoS configurations.

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Configuring QoS

Detailed Steps

Note

One side-effect of priority queueing is packet re-ordering. For IPSec packets, out-of-order packets that are not within the anti-replay window generate warning syslog messages. These warnings are false alarms in the case of priority queueing. You can configure the IPSec anti-replay window size to avoid possible false alarms. See the Configuration > VPN > IPSec > IPSec Rules > Enable Anti-replay window size option in the

“Adding Crypto Maps” section on page 63-10

.

Traffic shaping is not supported on the ASA 5580.

Step 1

Step 2

Step 3

Step 4

Configure a service policy on the Configuration > Firewall > Service Policy Rules pane according to


You can configure QoS as part of a new service policy rule, or you can edit an existing service policy.

For traffic shaping, all traffic on an interface must be shaped. You can only use the

class-default

class map, which is automatically created by the adaptive security appliance, and which matches all traffic.

You cannot configure a separate traffic shaping rule on the same interface for which you configure a priority queueing rule (see the

“Creating a Policy for Standard Priority Queueing and/or Policing” section on page 49-7 ); you can, however, configure priority queueing for a subset of shaped traffic under

the traffic shaping rule. You also cannot configure traffic shaping for the global policy if you also enable priority queueing on any interfaces.


QoS

tab.

Click

Enable traffic shaping

, and configure the following fields:

•

Average Rate—Sets the average rate of traffic in bits per second over a given fixed time period, between 64000 and 154400000. Specify a value that is a multiple of 8000.

•

Burst Size—Sets the average burst size in bits that can be transmitted over a given fixed time period, between 2048 and 154400000. Specify a value that is a multiple of 128. If you do not specify the

Burst Size, the default value is equivalent to 4-milliseconds of traffic at the specified Average Rate.

For example, if the average rate is 1000000 bits per second, 4 ms worth = 1000000 * 4/1000 = 4000.

(Optional) To configure priority queueing for a subset of shaped traffic:

a.

b.

c.

Click

Enforce priority to selected shape traffic

.

Click

Configure

to identify the traffic that you want to prioritize.

You are prompted to identify the traffic for which you want to apply priority queueing.

After you identify the traffic (see the “Adding a Service Policy Rule for Through Traffic” section on page 29-8

), click

Next

.

d.

e.

Click

Enable priority for this flow

.

Click

Finish

.

You return to the QoS tab.

Note

For this type of priority queueing, you do

not

need to create a priority queue on an interface

(Configuration > Properties > Priority Queue).

Step 5

Click

Finish


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49-9

Configuring QoS

Step 6

Click

Apply

to send the configuration to the device.


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Configuring QoS

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49-11

Configuring QoS


49-12


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Configuring QoS

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Configuring QoS


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Configuring QoS

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Configuring QoS


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Configuring QoS


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P

A R T

1 1

Configuring Advanced Network Protection

C H A P T E R

50


Malware is malicious software that is installed on an unknowing host. Malware that attempts network activity such as sending private data (passwords, credit card numbers, key strokes, or proprietary data) can be detected by the Botnet Traffic Filter when the malware starts a connection to a known bad IP address. The Botnet Traffic Filter checks incoming and outgoing connections against a dynamic database of known bad domain names and IP addresses (the

blacklist

), and then logs or blocks any suspicious activity.

You can also supplement the Cisco dynamic database with blacklisted addresses of your choosing by adding them to a static blacklist; if the dynamic database includes blacklisted addresses that you think should not be blacklisted, you can manually enter them into a static

whitelist

. Whitelisted addresses still generate syslog messages, but because you are only targeting blacklist syslog messages, they are informational.

Note

If you do not want to use the Cisco dynamic database at all, because of internal requirements, you can use the static blacklist alone if you can identify all the malware sites that you want to target.

This chapter describes how to configure the Botnet Traffic Filter and includes the following sections:

•

•

•

•

•

•

•

•

Information About the Botnet Traffic Filter, page 50-1

Licensing Requirements for the Botnet Traffic Filter, page 50-5



Configuring the Botnet Traffic Filter, page 50-6

Monitoring the Botnet Traffic Filter, page 50-13


Feature History for the Botnet Traffic Filter, page 50-15

Information About the Botnet Traffic Filter

This section includes information about the Botnet Traffic Filter and includes the following topics:

•

•

•

Botnet Traffic Filter Address Categories, page 50-2

Botnet Traffic Filter Actions for Known Addresses, page 50-2

Botnet Traffic Filter Databases, page 50-2

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50-1

Chapter 50 Configuring the Botnet Traffic Filter


•

How the Botnet Traffic Filter Works, page 50-4

Botnet Traffic Filter Address Categories

Addresses monitored by the Botnet Traffic Filter include:

•

Known malware addresses—These addresses are on the blacklist identified by the dynamic database and the static blacklist.

•

•

Known allowed addresses—These addresses are on the whitelist. The whitelist is useful when an address is blacklisted by the dynamic database and also identified by the static whitelist.

Ambiguous addresses—These addresses are associated with multiple domain names, but not all of these domain names are on the blacklist. These addresses are on the

greylist

.

•

Unlisted addresses—These addresses are unknown, and not included on any list.

Botnet Traffic Filter Actions for Known Addresses

You can configure the Botnet Traffic Filter to log suspicious activity, and you can optionally configure it to block suspicious traffic automatically.

Unlisted addresses do not generate any syslog messages, but addresses on the blacklist, whitelist, and greylist generate syslog messages differentiated by type. See the

“Botnet Traffic Filter Syslog

Messaging” section on page 50-13


Botnet Traffic Filter Databases

The Botnet Traffic Filter uses two databases for known addresses. You can use both databases together, or you can disable use of the dynamic database and use the static database alone. This section includes the following topics:

•

•

•

Information About the Dynamic Database, page 50-2

Information About the Static Database, page 50-3

Information About the DNS Reverse Lookup Cache and DNS Host Cache, page 50-3

Information About the Dynamic Database

The Botnet Traffic Filter can receive periodic updates for the dynamic database from the Cisco update server. This database lists thousands of known bad domain names and IP addresses.

The adaptive security appliance uses the dynamic database as follows:

1.

When the domain name in a DNS reply matches a name in the dynamic database, the Botnet Traffic

Filter adds the name and IP address to the

DNS reverse lookup cache

.

2.

3.

When the infected host starts a connection to the IP address of the malware site, then the adaptive security appliance sends a syslog message informing you of the suspicious activity and optionally drops the traffic if you configured the adaptive security appliance to do so.

In some cases, the IP address itself is supplied in the dynamic database, and the Botnet Traffic Filter logs or drops any traffic to that IP address without having to inspect DNS requests.

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The database files are stored in running memory; they are not stored in flash memory. If you need to delete the database, use theConfiguration > Firewall > Botnet Traffic Filter > Botnet Database pane

Purge Botnet Database button instead. Be sure to first disable use of the database by unchecking the

Use

Botnet data dynamically downloaded from updater server

check box in the Configuration > Firewall

> Botnet Traffic Filter > Botnet Database > Dynamic Database Configuration area.

Note

To use the database, be sure to configure a domain name server for the adaptive security appliance so that it can access the URL.

To use the domain names in the dynamic database, you need to enable DNS packet inspection with

Botnet Traffic Filter snooping; the adaptive security appliance looks inside the DNS packets for the domain name and associated IP address.

Information About the Static Database

You can manually enter domain names or IP addresses (host or subnet) that you want to tag as bad names in a blacklist. Static blacklist entries are always designated with a Very High threat level. You can also enter names or IP addresses in a whitelist, so that names or addresses that appear on both the

dynamic

blacklist and the whitelist are identified only as whitelist addresses in syslog messages and reports. Note that you see syslog messages for whitelisted addresses even if the address is not also in the dynamic blacklist.

When you add a domain name to the static database, the adaptive security appliance waits 1 minute, and then sends a DNS request for that domain name and adds the domain name/IP address pairing to the

DNS host cache

. (This action is a background process, and does not affect your ability to continue configuring the adaptive security appliance). We recommend also enabling DNS packet inspection with Botnet

Traffic Filter snooping. The adaptive security appliance uses Botnet Traffic Filter snooping instead of the regular DNS lookup to resolve static blacklist domain names in the following circumstances:

•

•

The adaptive security appliance DNS server is unavailable.

A connection is initiated during the 1 minute waiting period before the adaptive security appliance sends the regular DNS request.

If DNS snooping is used, when an infected host sends a DNS request for a name on the static database, the adaptive security appliance looks inside the DNS packets for the domain name and associated IP address and adds the name and IP address to the DNS reverse lookup cache.

If you do not enable Botnet Traffic Filter snooping, and one of the above circumstances occurs, then that traffic will not be monitored by the Botnet Traffic Filter.

Information About the DNS Reverse Lookup Cache and DNS Host Cache

When you use the dynamic database with DNS snooping, entries are added to the DNS reverse lookup cache. If you use the static database, entries are added to the DNS host cache (see the

“Information

About the Static Database” section on page 50-3 about using the static database with DNS snooping and

the DNS reverse lookup cache).

Entries in the DNS reverse lookup cache and the DNS host cache have a time to live (TTL) value provided by the DNS server. The largest TTL value allowed is 1 day (24 hours); if the DNS server provides a larger TTL, it is truncated to 1 day maximum.

For the DNS reverse lookup cache, after an entry times out, the adaptive security appliance renews the entry when an infected host initiates a connection to a known address, and DNS snooping occurs.

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For the DNS host cache, after an entry times out, the adaptive security appliance periodically requests a refresh for the entry.

For the DNS host cache, the maximum number of blacklist entries and whitelist entries is 1000 each.

Table 50-1 lists the maximum number of entries in the DNS reverse lookup cache per model.

Table 50-1

ASA Model

ASA 5505

ASA 5510

ASA 5520

ASA 5540

ASA 5550

ASA 5580

DNS Reverse Lookup Cache Entries per Model

Maximum Entries

5000

10,000

20,000

40,000

40,000

100,000

How the Botnet Traffic Filter Works

Figure 50-1

shows how the Botnet Traffic Filter works with the dynamic database plus DNS inspection with Botnet Traffic Filter snooping.

Figure 50-1 How the Botnet Traffic Filter Works with the Dynamic Database

Security Appliance

1

DNS Request: bad.example.com

DNS

Reverse

Lookup Cache

3a. Match?

Dynamic

Database

2a. Add

1a. Match?

DNS Snoop

Infected

Host

3

Connection to:

209.165.201.3

Botnet Traffic

Filter

3b. Send

Syslog Message/Drop Traffic

Syslog Server

Internet

DNS Server

2

DNS Reply:

209.165.201.3

Malware Home Site

209.165.201.3

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Licensing Requirements for the Botnet Traffic Filter

Figure 50-2 shows how the Botnet Traffic Filter works with the static database.

Figure 50-2 How the Botnet Traffic Filter Works with the Static Database

Infected

Host

3

Connection to:

209.165.201.3

DNS


Host Cache

2a. Add

Static

1

Database

Add entry: bad.example.com

DNS Server

3a. Match?

1a. DNS Request: bad.example.com

2

DNS Reply:

209.165.201.3

Internet

Botnet Traffic

Filter

3b. Send

Syslog Message/Drop Traffic

Syslog Server

Malware Home Site

209.165.201.3

Licensing Requirements for the Botnet Traffic Filter


Model

All models


You need the following licenses:

•

•

Botnet Traffic Filter License.

Strong Encryption (3DES/AES) License to download the dynamic database.








Does not support replication of the DNS reverse lookup cache, DNS host cache, or the dynamic database in Stateful Failover.

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IPv6 Guidelines



•

TCP DNS traffic is not supported.

•

You can add up to 1000 blacklist entries and 1000 whitelist entries in the static database.


By default, the Botnet Traffic Filter is disabled, as is use of the dynamic database.

For DNS inspection, which is enabled by default, Botnet Traffic Filter snooping is disabled by default.



•

•

•

•

•

•

•

Task Flow for Configuring the Botnet Traffic Filter, page 50-6

Configuring the Dynamic Database, page 50-7

Enabling DNS Snooping, page 50-9

Adding Entries to the Static Database, page 50-8

Enabling Traffic Classification and Actions for the Botnet Traffic Filter, page 50-10

Blocking Botnet Traffic Manually, page 50-12

Searching the Dynamic Database, page 50-13

Task Flow for Configuring the Botnet Traffic Filter

To configure the Botnet Traffic Filter, perform the following steps:

Step 1

Step 2

Step 3

Enable use of the dynamic database. See the

“Configuring the Dynamic Database” section on page 50-7 .

This procedure enables database updates from the Cisco update server, and also enables use of the downloaded dynamic database by the adaptive security appliance. Disallowing use of the downloaded database is useful in multiple context mode so you can configure use of the database on a per-context basis.

(Optional) Add static entries to the database. See the

“Adding Entries to the Static Database” section on page 50-8 .

This procedure lets you augment the dynamic database with domain names or IP addresses that you want to blacklist or whitelist. You might want to use the static database instead of the dynamic database if you do not want to download the dynamic database over the Internet.

Enable DNS snooping. See the

“Enabling DNS Snooping” section on page 50-9 .

This procedure enables inspection of DNS packets, compares the domain name with those in the dynamic database or the static database (when a DNS server for the adaptive security appliance is unavailable), and adds the name and IP address to the DNS reverse lookup cache. This cache is then used by the Botnet Traffic Filter when connections are made to the suspicious address.


50-6 OL-20339-01



Step 4

Step 5

Enable traffic classification and actions for the Botnet Traffic Filter. See the

“Enabling Traffic

Classification and Actions for the Botnet Traffic Filter” section on page 50-10

.

This procedure enables the Botnet Traffic Filter, which compares the source and destination IP address in each initial connection packet to the IP addresses in the dynamic database, static database, DNS reverse lookup cache, and DNS host cache, and sends a syslog message or drops any matching traffic.

(Optional) Block traffic manually based on syslog message information. See the

“Blocking Botnet

Traffic Manually” section on page 50-12 .

If you choose not to block malware traffic automatically, you can block traffic manually by configuring an access rule to deny traffic, or by using the

shun

command in the Command Line Interface tool to block all traffic to and from a host.

Configuring the Dynamic Database

This procedure enables database updates, and also enables use of the downloaded dynamic database by the adaptive security appliance. Disabling use of the downloaded database is useful in multiple context mode so you can configure use of the database on a per-context basis.

By default, downloading and using the dynamic database is disabled.

Prerequisites

Enable adaptive security appliance use of a DNS server in the Device Management > DNS > DNS Client

> DNS Lookup area. In multiple context mode, enable DNS per context.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

Enable downloading of the dynamic database.

•

In Single mode, choose the

Configuration > Firewall > Botnet Traffic Filter > Botnet Database

pane, then check the

Enable Botnet Updater Client

check box.

•

In multiple context mode in the System execution space, choose the

Configuration > Device

Management > Botnet Database

pane, then check the

Enable Botnet Updater Client

check box.

This setting enables downloading of the dynamic database from the Cisco update server. In multiple context mode, enter this command in the system execution space. If you do not have a database already installed on the adaptive security appliance, it downloads the database after approximately 2 minutes.

The update server determines how often the adaptive security appliance polls the server for future updates, typically every hour.

(Multiple context mode only) In multiple context mode, click

Apply

. Then change to the context where you want to configure the Botnet Traffic Filter by double-clicking the context name in the Device List.

In the Configuration > Firewall > Botnet Traffic Filter > Botnet Database > Dynamic Database

Configuration area, check the

Use Botnet data dynamically downloaded from updater server

check box.

Click

Apply

.

(Optional) If you want to later remove the database from running memory, perform the following steps:

a.

Disable use of the database by unchecking the


check box.

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Configuring the Botnet Traffic Filter b.

c.

d.

e.

Click

Apply

.

Click

Purge Botnet Database

.

To redownload the database, re-check the


check box.

Click

Apply

.

Note

The Fetch Botnet Database button is for testing purposes only; it downloads and verifies the dynamic database, but does not store it in running memory.

For information about the Search Dynamic Database area, see the

“Searching the Dynamic Database” section on page 50-13 .

What to Do Next

See the

“Adding Entries to the Static Database” section on page 50-8 .

Adding Entries to the Static Database

The static database lets you augment the dynamic database with domain names or IP addresses that you want to blacklist or whitelist. Static blacklist entries are always designated with a Very High threat level.

See the

“Information About the Static Database” section on page 50-3


Prerequisites

•

•

In multiple context mode, perform this procedure in the context execution space.

Enable adaptive security appliance use of a DNS server in the Device Management > DNS > DNS

Client > DNS Lookup area. In multiple context mode, enable DNS per context.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Choose the

Configuration > Firewall > Botnet Traffic Filter > Black

or White List pane, click

Add

for the Whitelist or Blacklist.

The Enter hostname or IP Address dialog box appears.

In the Addresses field, enter one or more domain names, IP addresses, and IP address/netmasks.

Enter multiple entries separated by commas, spaces, lines, or semi-colons. You can enter up to 1000 entries for each type.

Click

OK

.

Click

Apply

.

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What to Do Next

See the

“Enabling DNS Snooping” section on page 50-9 .

Enabling DNS Snooping

This procedure enables inspection of DNS packets and enables Botnet Traffic Filter snooping, which compares the domain name with those on the dynamic database or static database, and adds the name and IP address to the Botnet Traffic Filter DNS reverse lookup cache. This cache is then used by the

Botnet Traffic Filter when connections are made to the suspicious address.

Prerequisites

•

•


You must first configure DNS inspection for traffic that you want to snoop using the Botnet Traffic

Filter. See the “DNS Inspection” section on page 37-1

and

Chapter 29, “Configuring a Service

Policy,” for detailed information about configuring advanced DNS inspection options using the

Modular Policy Framework.

Note

You can also configure DNS snooping directly in the Configuration > Firewall > Service

Policy Rules > Rule Actions > Protocol Inspection > Select DNS Inspect Map dialog box by checking the

Enable Botnet traffic filter DNS snooping

check box.

Restrictions

TCP DNS traffic is not supported.

Default DNS Inspection Configuration and Recommended Configuration

The default configuration for DNS inspection inspects all UDP DNS traffic on all interfaces, and does not have DNS snooping enabled.

We suggest that you enable DNS snooping only on interfaces where external DNS requests are going.

Enabling DNS snooping on all UDP DNS traffic, including that going to an internal DNS server, creates unnecessary load on the adaptive security appliance.

For example, if the DNS server is on the outside interface, you should enable DNS inspection with snooping for all UDP DNS traffic on the outside interface.

Detailed Steps

Step 1

Step 2

Step 3

Choose the

Configuration > Firewall > Botnet Traffic Filter > DNS Snooping

pane.

All existing service rules that include DNS inspection are listed in the table.

For each rule for which you want to enable DNS snooping, in the DNS Snooping Enabled column, check the check box.

Click

Apply

.

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50-9



What to Do Next

See the

“Enabling Traffic Classification and Actions for the Botnet Traffic Filter” section on page 50-10

.

Enabling Traffic Classification and Actions for the Botnet Traffic Filter

This procedure enables the Botnet Traffic Filter. The Botnet Traffic Filter compares the source and destination IP address in each initial connection packet to the following:

•

Dynamic database IP addresses

•

•

Static database IP addresses

DNS reverse lookup cache (for dynamic database domain names)

•

DNS host cache (for static database domain names)

When an address matches, the adaptive security appliance sends a syslog message. The only additional action currently available is to drop the connection.

Prerequisites


Recommended Configuration

Although DNS snooping is not required, we recommend configuring DNS snooping for maximum use of the Botnet Traffic Filter (see the

“Enabling DNS Snooping” section on page 50-9

). Without DNS snooping for the dynamic database, the Botnet Traffic Filter uses only the static database entries, plus any IP addresses in the dynamic database; domain names in the dynamic database are not used.

We recommend enabling the Botnet Traffic Filter on all traffic on the Internet-facing interface, and enabling dropping of traffic with a severity of moderate and higher.

Detailed Steps

50-10

Step 1

Step 2

Step 3

Choose the

Configuration > Firewall > Botnet Traffic Filter > Traffic Settings

pane.

To enable the Botnet Traffic Filter on specified traffic, perform the following steps:

a.

In the Traffic Classification area, check the

Traffic Classified

check box for each interface on which you want to enable the Botnet Traffic Filter.

b.

You can configure a global classification that applies to all interfaces by checking the Traffic

Classified check box for Global (All Interfaces). If you configure an interface-specific classification, the settings for that interface overrides the global setting.

For each interface, from the

ACL Used

drop-down list choose either --ALL TRAFFIC-- (the default), or any access list configured on the adaptive security appliance.

For example, you might want to monitor all port 80 traffic on the outside interface.

To add or edit access lists, click

Manage ACL

to bring up the ACL Manager. See the

Chapter 15,

“Using the ACL Manager,”


(Optional) To treat greylisted traffic as blacklisted traffic for action purposes, in the Ambiguous Traffic

Handling area, check the

Treat ambiguous (greylisted) traffic as malicious (blacklisted) traffic

check box.


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Step 4

If you do not enable this option, greylisted traffic will not be dropped if you configure a rule in the

Blacklisted Traffic Actions area. See the

“Botnet Traffic Filter Address Categories” section on page 50-2

for more information about the greylist.

(Optional) To automatically drop malware traffic, perform the following steps.

To manually drop traffic, see the

“Blocking Botnet Traffic Manually” section on page 50-12 .

a.

In the Blacklisted Traffic Actions area, click

Add

.

The Add Blacklisted Traffic Action dialog box appears.

b.

c.

From the Interface drop-down list, choose the interface on which you want to drop traffic. Only interfaces on which you enabled Botnet Traffic Filter traffic classification are available.

In the Threat Level area, choose one of the following options to drop traffic specific threat levels.

The default level is a range between Moderate and Very High.

Note

We highly recommend using the default setting unless you have strong reasons for changing the setting.

•

Value—Specify the threat level you want to drop:

–

–

Very Low

Low

–

–

–

Moderate

High

Very High

Note

Static blacklist entries are always designated with a Very High threat level.

• d.

Range—Specify a range of threat levels.

In the ACL Used area, from the

ACL Used

drop-down list choose either --ALL TRAFFIC-- (the default), or any access list configured on the adaptive security appliance.

Note

Be sure the access list is a subset of the traffic you specified in the Traffic Classification area.

e.

f.

To add or edit access lists, click

Manage

to bring up the ACL Manager. See

Chapter 15, “Using the

ACL Manager,”


Click

OK

.

You return to the Traffic Settings pane.

If you want to apply additional rules to a given interface, repeat steps

a through e .

Make sure you do not specify overlapping traffic in multiple rules for a given interface. Because you cannot control the exact order that rules are matched, overlapping traffic means you do not know which command will be matched. For example, do not specify both a rule that matches --ALL

TRAFFIC-- as well as a command with and access list for a given interface. In this case, the traffic might never match the command with the access list. Similarly, if you specify multiple commands with access lists, make sure each access list is unique, and that the networks do not overlap.

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Step 5

Click

Apply

.

Blocking Botnet Traffic Manually

If you choose not to block malware traffic automatically (see the

“Enabling Traffic Classification and

Actions for the Botnet Traffic Filter” section on page 50-10 ), you can block traffic manually by

configuring an access rule to deny traffic, or by using the

shun

command in the Command Line Interface tool to block all traffic to and from a host. For some messages, you can automatically configure access rules in ASDM.

For example, you receive the following syslog message:

ASA-4-338002: Dynamic Filter permitted black listed TCP traffic from inside:10.1.1.45/6798

(209.165.201.1/7890) to outside:209.165.202.129/80 (209.165.202.129/80), destination

209.165.202.129 resolved from dynamic list: bad.example.com

You can then perform one of the following actions:

•

Create an access rule to deny traffic.

For example, using the syslog message above, you might want to deny traffic from the infected host at 10.1.1.45 to the malware site at 209.165.202.129. Or, if there are many connections to different blacklisted addresses, you can create an access list to deny all traffic from 10.1.1.45 until you resolve the infection on the host computer.

For the following syslog messages, a reverse access rule can be automatically created from the Real

Time Log Viewer:

–

–

338001, 338002, 338003, 338004 (blacklist)

338201, 338202 (greylist)

See

Chapter 71, “Configuring Logging,”

and

Chapter 30, “Configuring Access Rules,” for more

information about creating an access rule.

Note

If you create a reverse access rule form a Botnet Traffic Filter syslog message, and you do not have any other access rules applied to the interface, then you might inadvertently block all traffic. Normally, without an access rule, all traffic from a high security to a low security interface is allowed. But when you apply an access rule, all traffic is denied except traffic that you explicitly permit. Because the reverse access rule is a deny rule, be sure to edit the resulting access policy for the interface to permit other traffic.

Access lists block all future connections. To block the current connection, if it is still active, enter the

clear conn

command. For example, to clear only the connection listed in the syslog message, enter the

clear conn address 10.1.1.45 address 209.165.202.129

command. See the



•

Shun the infected host.

Shunning blocks all connections from the host, so you should use an access list if you want to block connections to certain destination addresses and ports. To shun a host, enter the following command in Tools > Command Line Interface. To drop the current connection as well as blocking all future connections, enter the destination address, source port, destination port, and optional protocol.

shun

src_ip

[

dst_ip src_port dest_port

[

protocol

]]

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Monitoring the Botnet Traffic Filter

For example, to block future connections from 10.1.1.45, and also drop the current connection to the malware site in the syslog message, enter:

shun 10.1.1.45 209.165.202.129 6798 80

After you resolve the infection, be sure to remove the access list or the shun. To remove the shun, enter

no shun

src_ip

.

Searching the Dynamic Database

If you want to check if a domain name or IP address is included in the dynamic database, you can search the database for a string.

Detailed Steps

Step 1

Step 2

Step 3

Go to the Search Dynamic Database area:

•

In Single mode or within a context, choose the

Configuration > Firewall > Botnet Traffic Filter

> Botnet Database Update

pane.

•

In multiple context mode in the System execution space, choose the


Management > Botnet Database Update

pane.

In the Search string field, enter a string at least 3 characters in length, and click

Find Now

.

The first two matches are shown. To refine your search for a more specific match, enter a longer string.

To clear the displayed matches and the search string, click

Clear

, or you can just enter a new string and click

Find Now

to get a new display.


Whenever a known address is classified by the Botnet Traffic Filter, then a syslog message is generated.

You can also monitor Botnet Traffic Filter statistics and other parameters by entering commands on the adaptive security appliance. This section includes the following topics:

•

•

Botnet Traffic Filter Syslog Messaging, page 50-13

Botnet Traffic Filter Monitor Panes, page 50-14

Botnet Traffic Filter Syslog Messaging

The Botnet Traffic Filter generates detailed syslog messages numbered 338

nnn

. Messages differentiate between incoming and outgoing connections, blacklist, whitelist, or greylist addresses, and many other variables. (The greylist includes addresses that are associated with multiple domain names, but not all of these domain names are on the blacklist.)

See the

Cisco ASA 5500 Series System Log Messages

for detailed information about syslog messages.

For the following syslog messages, a reverse access rule can be automatically created from the Real Time

Log Viewer:

•

338001, 338002, 338003, 338004 (blacklist)

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50-13


•

338201, 338202 (greylist)

See

Chapter 71, “Configuring Logging.”

Botnet Traffic Filter Monitor Panes

To monitor the Botnet Traffic Filter, see the following panes:


Command

Home > Firewall Dashboard

Monitoring > Botnet Traffic Filter > Statistics

Monitoring > Botnet Traffic Filter > Real-time

Reports

Purpose

Shows the Top Botnet Traffic Filter Hits, which shows reports of the top

10 malware sites, ports, and infected hosts. This report is a snapshot of the data, and may not match the top 10 items since the statistics started to be collected. If you right-click an IP address, you can invoke the whois tool to learn more about the botnet site.

•

Top Malware Sites—Shows top malware sites.

•

•

Top Malware Ports—Shows top malware ports.

Top Infected Hosts—Shows the top infected hosts.

Shows how many connections were monitored and dropped with the

Botnet Traffic Filter, and how many of those connections match the whitelist, blacklist, and greylist. (The greylist includes addresses that are associated with multiple domain names, but not all of these domain names are on the blacklist.) The Details button shows how many packets at each threat level were classified or dropped.

Generates reports of the top 10 malware sites, ports, and infected hosts monitored. The top 10 malware-sites report includes the number of connections dropped, and the threat level and category of each site. This report is a snapshot of the data, and may not match the top 10 items since the statistics started to be collected.

If you right-click a site IP address, you can invoke the whois tool to learn more about the malware site. Reports can be saved as a PDF file.

Monitoring > Botnet Traffic Filter > Infected

Hosts

Generates reports about infected hosts. These reports contain detailed history about infected hosts, showing the correlation between infected hosts, visited malware sites, and malware ports. The Maximum

Connections option shows the 20 infected hosts with the most number of connections. The Latest Activity option shows the 20 hosts with the most recent activity. The Highest Threat Level option shows the 20 hosts that connected to the malware sites with the highest threat level. The Subnet option shows up to 20 hosts within the specified subnet.

Reports can be saved as a PDF file, as either the Current View or the

Whole Buffer. The Whole Buffer option shows all buffered infected-hosts information.

Monitoring > Botnet Traffic Filter > Updater

Client

Shows information about the updater server, including the server IP address, the next time the adaptive security appliance will connect with the server, and the database version last installed.

50-14


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Command

Monitoring > Botnet Traffic Filter > DNS

Snooping

Monitoring > Botnet Traffic Filter > Dynamic

Database

Monitoring > Botnet Traffic Filter > ASP Table

Hits

Purpose

Shows the Botnet Traffic Filter DNS snooping actual IP addresses and names. All inspected DNS data is included in this output, and not just matching names in the blacklist. DNS data from static entries are not included.

Shows information about the dynamic database, including when the dynamic database was last downloaded, the version of the database, how many entries the database contains, and 10 sample entries.

Shows the Botnet Traffic Filter rules that are installed in the accelerated security path.


•

•

To configure the syslog server, see


To block connections with an access rule, see Chapter 30, “Configuring Access Rules.”

Feature History for the Botnet Traffic Filter

Table 50-2


Table 50-2 Feature History for the Botnet Traffic Filter

Feature Name


Automatic blocking, and blacklist category and threat level reporting.

Platform

Releases

8.2(1)

8.2(2)



The Botnet Traffic Filter now supports automatic blocking of blacklisted traffic based on the threat level. You can also view the category and threat level of malware sites in statistics and reports.

The 1 hour timeout for reports for top hosts was removed; there is now no timeout.


Configuration > Firewall > Botnet Traffic Filter > Traffic

Settings, and Monitoring > Botnet Traffic Filter > Infected

Hosts.

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Feature History for the Botnet Traffic Filter


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C H A P T E R

51

Configuring Threat Detection

This chapter describes how to configure threat detection statistics and scanning threat detection and includes the following sections:

•

Information About Threat Detection, page 51-1

•

•

•

Configuring Basic Threat Detection Statistics, page 51-1

Configuring Advanced Threat Detection Statistics, page 51-5

Configuring Scanning Threat Detection, page 51-8

Information About Threat Detection

The threat detection feature consists of the following elements:

•

Different levels of statistics gathering for various threats.

Threat detection statistics can help you manage threats to your adaptive security appliance; for example, if you enable scanning threat detection, then viewing statistics can help you analyze the threat. You can configure two types of threat detection statistics:

–

Basic threat detection statistics—Includes information about attack activity for the system as a whole. Basic threat detection statistics are enabled by default and have no performance impact.

•

–

Advanced threat detection statistics—Tracks activity at an object level, so the adaptive security appliance can report activity for individual hosts, ports, protocols, or access lists. Advanced threat detection statistics can have a major performance impact, depending on the statistics gathered, so only the access list statistics are enabled by default.

Scanning threat detection, which determines when a host is performing a scan.

You can optionally shun any hosts determined to be a scanning threat.

Configuring Basic Threat Detection Statistics

Basic threat detection statistics include activity that might be related to an attack, such as a DoS attack.


•

•

•

Information About Basic Threat Detection Statistics, page 51-2



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•

•

•

Configuring Basic Threat Detection Statistics, page 51-4

Monitoring Basic Threat Detection Statistics, page 51-4

Feature History for Basic Threat Detection Statistics, page 51-4

Chapter 51 Configuring Threat Detection

Information About Basic Threat Detection Statistics

Using basic threat detection statistics, the adaptive security appliance monitors the rate of dropped packets and security events due to the following reasons:

•

Denial by access lists

•

•

•

Bad packet format (such as invalid-ip-header or invalid-tcp-hdr-length)

Connection limits exceeded (both system-wide resource limits, and limits set in the configuration)

•

DoS attack detected (such as an invalid SPI, Stateful Firewall check failure)

Basic firewall checks failed (This option is a combined rate that includes all firewall-related packet drops in this bulleted list. It does not include non-firewall-related drops such as interface overload, packets failed at application inspection, and scanning attack detected.)

•

•

•

•

Suspicious ICMP packets detected

Packets failed application inspection

Interface overload

Scanning attack detected (This option monitors scanning attacks; for example, the first TCP packet is not a SYN packet, or the TCP connection failed the 3-way handshake. Full scanning threat detection (see the

“Configuring Scanning Threat Detection” section on page 51-8 ) takes this

scanning attack rate information and acts on it by classifying hosts as attackers and automatically shunning them, for example.)

•

Incomplete session detection such as TCP SYN attack detected or no data UDP session attack detected

When the adaptive security appliance detects a threat, it immediately sends a system log message

(730100). The adaptive security appliance tracks two types of rates: the average event rate over an interval, and the burst event rate over a shorter burst interval. The burst rate interval is 1/30th of the average rate interval or 10 seconds, whichever is higher. For each received event, the adaptive security appliance checks the average and burst rate limits; if both rates are exceeded, then the adaptive security appliance sends two separate system messages, with a maximum of one message for each rate type per burst period.

Basic threat detection affects performance only when there are drops or potential threats; even in this scenario, the performance impact is insignificant.



Security Context Guidelines

Supported in single mode only. Multiple mode is not supported.



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Types of Traffic Monitored

Only through-the-box traffic is monitored; to-the-box traffic is not included in threat detection.


Basic threat detection statistics are enabled by default.

Table 51-1

lists the default settings. You can view all these default settings using the

show running-config all threat-detection

command in Tools > Command Line Interface.

Table 51-1 Basic Threat Detection Default Settings

Packet Drop Reason

•

•

DoS attack detected

Bad packet format

Trigger Settings

Average Rate Burst Rate

100 drops/sec over the last 600 seconds.

400 drops/sec over the last 10 second period.



•

•

Connection limits exceeded

Suspicious ICMP packets detected

Scanning attack detected

Incomplete session detected such as

TCP SYN attack detected or no data

UDP session attack detected

(combined)





Denial by access lists 400 drops/sec over the last 600 seconds.


320 drops/sec over the last

3600 seconds.


•

•

Basic firewall checks failed

Packets failed application inspection

Interface overload








3600 seconds.



600 seconds.


3600 seconds.



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This section describes how to configure basic threat detection statistics, including enabling or disabling it and changing the default limits.

Detailed Steps

Step 1

Step 2

To enable or disable basic threat detection, choose the

Configuration > Firewall > Threat Detection

pane, and check the

Enable Basic Threat Detection

check box.

Click

Apply

.

Monitoring Basic Threat Detection Statistics

To monitor basic threat detection statistics, perform the following task:

Path Purpose

Home > Firewall Dashboard > Traffic Overview Displays basic threat detection statistics.

For a description of each event type, see the

“Information About Basic

Threat Detection Statistics” section on page 51-2 .

Feature History for Basic Threat Detection Statistics



Table 51-2

Feature Name

Burst rate interval changed to 1/30th of the average rate.

Feature History for Basic Threat Detection Statistics

Basic threat detection statistics

Improved memory usage

Platform

Releases

8.0(2)

8.2(1)

8.3(1)


Basic threat detection statistics was introduced.


Firewall > Threat Detection, Home > Firewall Dashboard >

Traffic Overview.

In earlier releases, the burst rate interval was 1/60th of the average rate. To maximize memory usage, the sampling interval was reduced to 30 times during the average rate.

The memory usage for threat detection was improved.

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Configuring Advanced Threat Detection Statistics


You can configure the adaptive security appliance to collect extensive statistics. This section includes the following topics:

•

Information About Advanced Threat Detection Statistics, page 51-5

•

•

•

•

•



Configuring Advanced Threat Detection Statistics, page 51-5

Monitoring Advanced Threat Detection Statistics, page 51-7

Feature History for Advanced Threat Detection Statistics, page 51-8

Information About Advanced Threat Detection Statistics

Advanced threat detection statistics show both allowed and dropped traffic rates for individual objects such as hosts, ports, protocols, or access lists.

Caution

Enabling advanced statistics can affect the adaptive security appliance performance, depending on the type of statistics enabled. Enabling host statistics affects performance in a significant way; if you have a high traffic load, you might consider enabling this type of statistics temporarily. Port statistics, however, has modest impact.




Only TCP Intercept statistics are available in multiple mode.






By default, statistics for access lists are enabled.


By default, statistics for access lists are enabled. To enable other statistics, perform the following steps.

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Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Choose the


pane.

In the Scanning Threat Statistics area, choose one of the following options:

•

•

Enable

all

statistics—Click the

Enable All Statistics

radio button.

Disable

all

statistics—Click the

Disable All Statistics

radio button.

•

Enable only certain statistics—Click the

Enable Only Following Statistics

radio button.

If you chose to

Enable Only Following Statistics

, then check one or more of the following check boxes:

•

•

Hosts

—Enables host statistics. The host statistics accumulate for as long as the host is active and in the scanning threat host database. The host is deleted from the database (and the statistics cleared) after 10 minutes of inactivity.

Access Rules

(enabled by default)—Enables statistics for access rules.

•

•

Port

—Enables statistics for TCP and UDP ports.

Protocol

—Enables statistics for non-TCP/UDP IP protocols.

• TCP-Intercept

—Enables statistics for attacks intercepted by TCP Intercept (see the

“Configuring

Connection Settings” section on page 48-8 to enable TCP Intercept).

For host, port, and protocol statistics, you can change the number of rate intervals collected. In the Rate

Intervals area, choose

1 hour

,

1 and 8 hours

, or

1, 8 and 24 hours

for each statistics type. The default interval is

1 hour

, which keeps the memory usage low.

For TCP Intercept statistics, you can set the following options in the TCP Intercept Threat Detection area:

•

Monitoring Window Size

—Sets the size of the history monitoring window, between 1 and 1440 minutes. The default is 30 minutes. The adaptive security appliance samples the number of attacks

30 times during the rate interval, so for the default 30 minute period, statistics are collected every

60 seconds.

•

•

Burst Threshold Rate

—Sets the threshold for syslog message generation, between 25 and

2147483647. The default is 400 per second. When the burst rate is exceeded, syslog message 733104 is generated.

Average Threshold Rate

—Sets the average rate threshold for syslog message generation, between

25 and 2147483647. The default is 200 per second. When the average rate is exceeded, syslog message 733105 is generated.

Click

Set Default

to restore the default values.

Click

Apply

.

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Monitoring Advanced Threat Detection Statistics

To monitor advanced threat detection statistics, perform one of the following tasks:

Path

Home > Firewall Dashboard > Top 10 Access

Rules

Home > Firewall Dashboard > Top Usage

Statistics

Purpose

Displays the top 10 statistics.

For the Top 10 Access Rules, permitted and denied traffic are not differentiated in this display. In the Traffic Overview > Dropped Packets

Rate graph, you can track access list denies.

The Top 10 Sources and Top 10 Destinations tabs show statistics for hosts.

The Top 10 Services tab shows statistics for both ports and protocols (both must be enabled for the display), and shows the combined statistics of

TCP/UDP port and IP protocol types. TCP (protocol 6) and UDP

(protocol 17) are not included in the display for IP protocols; TCP and

UDP ports are, however, included in the display for ports. If you only enable statistics for one of these types, port or protocol, then you will only view the enabled statistics.

The Top Ten Protected Servers under SYN Attack area shows the TCP

Intercept statistics. The display includes the top 10 protected servers under attack. The

detail

button shows history sampling data. The adaptive security appliance samples the number of attacks 30 times during the rate interval, so for the default 30 minute period, statistics are collected every

60 seconds.

From the Interval drop-down list, choose

Last 1 hour

,

Last 8 hour

, or

Last 24 hour

.

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Configuring Scanning Threat Detection

Feature History for Advanced Threat Detection Statistics

Table 51-3



Feature History for Advanced Threat Detection Statistics

Feature Name

Advanced threat detection statistics

TCP Intercept statistics

Customize host statistics rate intervals


Customize port and protocol statistics rate intervals


Platform

Releases

8.0(2)


Advanced threat detection statistics was introduced.

The following screens were introduced: Configuration >

Firewall > Threat Detection, Home > Firewall Dashboard >

Top 10 Access Rules, Home > Firewall Dashboard > Top

Usage Status, Home > Firewall Dashboard > Top 10

Protected Servers Under SYN Attack.

8.0(4)/8.1(2) TCP Intercept statistics were introduced.

8.1(2)

8.2(1)

8.3(1)

8.3(1)


Configuration > Firewall > Threat Detection, Home >

Firewall Dashboard > Top 10 Protected Servers Under SYN

Attack.

You can now customize the number of rate intervals for which statistics are collected. The default number of rates was changed from 3 to 1.


Firewall > Threat Detection.


You can now customize the number of rate intervals for which statistics are collected. The default number of rates was changed from 3 to 1.






•

Information About Scanning Threat Detection, page 51-9

•

•

•



Configuring Scanning Threat Detection, page 51-10

51-8


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•

•

Feature History for Scanning Threat Detection, page 51-11

Feature History for Scanning Threat Detection, page 51-11


Information About Scanning Threat Detection

A typical scanning attack consists of a host that tests the accessibility of every IP address in a subnet (by scanning through many hosts in the subnet or sweeping through many ports in a host or subnet). The scanning threat detection feature determines when a host is performing a scan. Unlike IPS scan detection that is based on traffic signatures, the adaptive security appliance scanning threat detection feature maintains an extensive database that contains host statistics that can be analyzed for scanning activity.

The host database tracks suspicious activity such as connections with no return activity, access of closed service ports, vulnerable TCP behaviors such as non-random IPID, and many more behaviors.

If the scanning threat rate is exceeded, then the adaptive security appliance sends a syslog message

(733101), and optionally shuns the attacker. The adaptive security appliance tracks two types of rates: the average event rate over an interval, and the burst event rate over a shorter burst interval. The burst event rate is 1/30th of the average rate interval or 10 seconds, whichever is higher. For each event detected that is considered to be part of a scanning attack, the adaptive security appliance checks the average and burst rate limits. If either rate is exceeded for traffic sent from a host, then that host is considered to be an attacker. If either rate is exceeded for traffic received by a host, then that host is considered to be a target.

Caution

The scanning threat detection feature can affect the adaptive security appliance performance and memory significantly while it creates and gathers host- and subnet-based data structure and information.




Supported in single mode only. Multiple mode is not supported.




•


•

Traffic that is denied by an access list does not trigger scanning threat detection; only traffic that is allowed through the adaptive security appliance and that creates a flow is affected by scanning threat detection.

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Table 51-4 lists the default rate limits for scanning threat detection.

Table 51-4 Default Rate Limits for Scanning Threat Detection

Average Rate



Burst Rate



The burst rate is calculated as the average rate every

N

seconds, where

N

is the burst rate interval. The burst rate interval is 1/60th of the rate interval or 10 seconds, whichever is larger.


Detailed Steps

Step 1

Step 2

Step 3

Step 4

Choose the


pane, and check the

Enable Scanning

Threat Detection

check box.

(Optional) To automatically terminate a host connection when the adaptive security appliance identifies the host as an attacker, check the

Shun Hosts detected by scanning threat

check box.

(Optional) To except host IP addresses from being shunned, enter an address in the Networks excluded from shun field.

You can enter multiple addresses or subnets separated by commas. To choose a network from the list of

IP address objects, click the

...

button.

(Optional) To set the duration of a shun for an attacking host, check the

Set Shun Duration

check box and enter a value between 10 and 2592000 seconds. The default length is 3600 seconds (1 hour). To restore the default value, click

Set Default

.

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Feature History for Scanning Threat Detection

Table 51-5

Table 51-5


Feature History for Scanning Threat Detection

Feature Name

Scanning threat detection

Shun duration



Platform

Releases

8.0(2)


Scanning threat detection was introduced.



8.0(4)/8.1(2) You can now set the shun duration,

8.2(1)

8.3(1)





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51-12


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51-14


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51-16


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51-18


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Using Protection Tools

C H A P T E R

52

This chapter describes some of the many tools available to protect your network and includes the following sections:

•

Preventing IP Spoofing, page 52-1

•

•

•

Configuring the Fragment Size, page 52-2

Configuring TCP Options, page 52-3

Configuring IP Audit for Basic IPS Support, page 52-5

Preventing IP Spoofing

This section lets you enable Unicast Reverse Path Forwarding on an interface. Unicast RPF guards against IP spoofing (a packet uses an incorrect source IP address to obscure its true source) by ensuring that all packets have a source IP address that matches the correct source interface according to the routing table.

Normally, the adaptive security appliance only looks at the destination address when determining where to forward the packet. Unicast RPF instructs the adaptive security appliance to also look at the source address; this is why it is called Reverse Path Forwarding. For any traffic that you want to allow through the adaptive security appliance, the adaptive security appliance routing table must include a route back to the source address. See RFC 2267 for more information.

For outside traffic, for example, the adaptive security appliance can use the default route to satisfy the

Unicast RPF protection. If traffic enters from an outside interface, and the source address is not known to the routing table, the adaptive security appliance uses the default route to correctly identify the outside interface as the source interface.

If traffic enters the outside interface from an address that is known to the routing table, but is associated with the inside interface, then the adaptive security appliance drops the packet. Similarly, if traffic enters the inside interface from an unknown source address, the adaptive security appliance drops the packet because the matching route (the default route) indicates the outside interface.

Unicast RPF is implemented as follows:

•

ICMP packets have no session, so each packet is checked.

•

UDP and TCP have sessions, so the initial packet requires a reverse route lookup. Subsequent packets arriving during the session are checked using an existing state maintained as part of the session. Non-initial packets are checked to ensure they arrived on the same interface used by the initial packet.


52-1 OL-20339-01

Chapter 52 Using Protection Tools

Configuring the Fragment Size

Configuration > Firewall > Advanced > Anti-Spoofing Fields

•

Interface—Lists the interface names.

•

Anti-Spoofing Enabled—Shows whether an interface has Unicast RPF enabled, Yes or No.

•

•

Enable—Enables Unicast RPF for the selected interface.

Disable—Disables Unicast RPF for the selected interface.

Configuring the Fragment Size

By default, the adaptive security appliance allows up to 24 fragments per IP packet, and up to 200 fragments awaiting reassembly. You might need to let fragments on your network if you have an application that routinely fragments packets, such as NFS over UDP. However, if you do not have an application that fragments traffic, we recommend that you do not allow fragments through the adaptive security appliance. Fragmented packets are often used as DoS attacks.

To modify the IP fragment database parameters of an interface, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Choose the

Configuration > Firewall > Advanced > Fragment

pane, choose the interface to change in the Fragment table, and click

Edit

.

The Edit Fragment dialog box appears.

In the Size field, set the maximum number of packets that can be in the IP reassembly database waiting for reassembly. The default is 200.

In the Chain field, set the maximum number of packets into which a full IP packet can be fragmented.

The default is 24 packets.

In the Timeout field, set the maximum number of seconds to wait for an entire fragmented packet to arrive.

The timer starts after the first fragment of a packet arrives. If all fragments of the packet do not arrive by the number of seconds specified, all fragments of the packet that were already received will be discarded. The default is 5 seconds.

Click

OK

.

Click

Apply

.

To view the fragment statistics, click

Show Fragment

. See the

“Show Fragment” section on page 52-2


Show Fragment

The Configuration > Properties > Fragment > Show Fragment pane displays the current IP fragment database statistics for each interface.

Fields

•

Size—

Display only

. Displays the number of packets in the IP reassembly database waiting for reassembly. The default is 200.

•

Chain—

Display only

. Displays the number of packets into which a full IP packet can be fragmented.

The default is 24 packets.

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Configuring TCP Options

•

•

•

•

•

•

Timeout—

Display only

. Displays the number of seconds to wait for an entire fragmented packet to arrive. The timer starts after the first fragment of a packet arrives. If all fragments of the packet do not arrive by the number of seconds displayed, all fragments of the packet that were already received will be discarded. The default is 5 seconds.

Threshold—

Display only

. Displays the IP packet threshold, or the limit after which no new chains can be created in the reassembly module.

Queue—

Display only

. Displays the number of IP packets waiting in the queue for reassembly.

Assembled—

Display only

. Displays the number of IP packets successfully reassembled.

Fail—

Display only

. Displays the number of failed reassembly attempts.

Overflow—

Display only

. Displays the number of IP packets in the overflow queue.


The Configuration > Properties > TCP Options pane lets you set parameters for TCP connections.

Fields

•

Inbound and Outbound Reset—Sets whether to reset denied TCP connections for inbound and outbound traffic.

–

Interface—Shows the interface name.

•

–

–

Inbound Reset—Shows the interface reset setting for inbound TCP traffic, Yes or No. Enabling this setting causes the adaptive security appliance to send TCP resets for all inbound TCP sessions that attempt to transit the adaptive security appliance and are denied by the adaptive security appliance based on access lists or AAA settings. Traffic between same security level interfaces is also affected. When this option is not enabled, the adaptive security appliance silently discards denied packets.

Outbound Reset—Shows the interface reset setting for outbound TCP traffic, Yes or No.

Enabling this setting causes the adaptive security appliance to send TCP resets for all outbound

TCP sessions that attempt to transit the adaptive security appliance and are denied by the adaptive security appliance based on access lists or AAA settings. Traffic between same security level interfaces is also affected. When this option is not enabled, the adaptive security appliance silently discards denied packets.

–

Edit—Sets the inbound and outbound reset settings for the interface.

Other Options—Sets additional TCP options.

–

–

Send Reset Reply for Denied Outside TCP Packets—Enables resets for TCP packets that terminate at the least secure interface and are denied by the adaptive security appliance based on access lists or AAA settings. When this option is not enabled, the adaptive security appliance silently discards denied packets. If you enable Inbound Resets for the least secure interface (see

TCP Reset Settings

), then you do not also have to enable this setting; Inbound Resets handle to-the-adaptive security appliance traffic as well as through the adaptive security appliance traffic.

Force Maximum Segment Size for TCP—Sets the maximum TCP segment size in bytes, between 48 and any maximum number. The default value is 1380 bytes. You can disable this feature by setting the bytes to 0. Both the host and the server can set the maximum segment size when they first establish a connection. If either maximum exceeds the value you set here, then

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–

–

the adaptive security appliance overrides the maximum and inserts the value you set. For example, if you set a maximum size of 1200 bytes, when a host requests a maximum size of

1300 bytes, then the adaptive security appliance alters the packet to request 1200 bytes.

Force Minimum Segment Size for TCP

—

Overrides the maximum segment size to be no less than the number of bytes you set, between 48 and any maximum number. This feature is disabled by default (set to 0). Both the host and the server can set the maximum segment size when they first establish a connection. If either maximum is less than the value you set for the

Force Minimum Segment Size for TCP Proxy field, then the adaptive security appliance overrides the maximum and inserts the “minimum” value you set (the minimum value is actually the smallest maximum allowed). For example, if you set a minimum size of 400 bytes, if a host requests a maximum value of 300 bytes, then the adaptive security appliance alters the packet to request 400 bytes.

Force TCP Connection to Linger in TIME_WAIT State for at Least 15 Seconds

—

Forces each

TCP connection to linger in a shortened TIME_WAIT state of at least 15 seconds after the final normal TCP close-down sequence. You might want to use this feature if an end host application default TCP terminating sequence is a simultaneous close. The default behavior of the adaptive security appliance is to track the shutdown sequence and release the connection after two FINs and the ACK of the last FIN segment. This quick release heuristic enables the adaptive security appliance to sustain a high connection rate, based on the most common closing sequence, known as the normal close sequence. However, in a simultaneous close, both ends of the transaction initiate the closing sequence, as opposed to the normal close sequence where one end closes and the other end acknowledges prior to initiating its own closing sequence (see RFC 793). Thus, in a simultaneous close, the quick release forces one side of the connection to linger in the

CLOSING state. Having many sockets in the CLOSING state can degrade the performance of an end host. For example, some WinSock mainframe clients are known to exhibit this behavior and degrade the performance of the mainframe server. Using this feature creates a window for the simultaneous close down sequence to complete.

TCP Reset Settings

The Configuration > Properties > TCP Options > TCP Reset Settings dialog box sets the inbound and outbound reset settings for an interface.

Fields

•

Send Reset Reply for Denied Inbound TCP Packets—Sends TCP resets for all inbound TCP sessions that attempt to transit the adaptive security appliance and are denied by the adaptive security appliance based on access lists or AAA settings. Traffic between same security level interfaces is also affected. When this option is not enabled, the adaptive security appliance silently discards denied packets.

You might want to explicitly send resets for inbound traffic if you need to reset identity request

(IDENT) connections. When you send a TCP RST (reset flag in the TCP header) to the denied host, the RST stops the incoming IDENT process so that you do not have to wait for IDENT to time out.

Waiting for IDENT to time out can cause traffic to slow because outside hosts keep retransmitting the SYN until the IDENT times out, so the

service resetinbound

command might improve performance.

•

Send Reset Reply for Denied Outbound TCP Packets—Sends TCP resets for all outbound TCP sessions that attempt to transit the adaptive security appliance and are denied by the adaptive security appliance based on access lists or AAA settings. Traffic between same security level

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Configuring IP Audit for Basic IPS Support

interfaces is also affected. When this option is not enabled, the adaptive security appliance silently discards denied packets. This option is enabled by default. You might want to disable outbound resets to reduce the CPU load during traffic storms, for example.


The IP audit feature provides basic IPS support for the adaptive security appliance that does not have an

AIP SSM. It supports a basic list of signatures, and you can configure the adaptive security appliance to perform one or more actions on traffic that matches a signature.


•

IP Audit Policy, page 52-5

•

•

•

Add/Edit IP Audit Policy Configuration, page 52-6

IP Audit Signatures, page 52-6

IP Audit Signature List, page 52-7

IP Audit Policy

The Configuration > Properties > IP Audit > IP Audit Policy pane lets you add audit policies and assign them to interfaces. You can assign an attack policy and an informational policy to each interface. The attack policy determines the action to take with packets that match an attack signature; the packet might be part of an attack on your network, such as a DoS attack. The informational policy determines the action to take with packets that match an informational signature; the packet is not currently attacking your network, but could be part of an information-gathering activity, such as a port sweep. For a

complete list of signatures, see the IP Audit Signature List .

•

•

•

Fields

•

Name—Shows the names of the defined IP audit policies. Although the default actions for a named policy are listed in this table (“--Default Action--”), they are not named policies that you can assign to an interface. Default actions are used by named policies if you do not set an action for the policy.

You can modify the default actions by selecting them and clicking the Edit button.

•

•

Type—Shows the policy type, either Attack or Info.

Action—Shows the actions taken against packets that match the policy, Alarm, Drop, and/or Reset.

Multiple actions can be listed.

•

Add—Adds a new IP audit policy.

Edit—Edits an IP audit policy or the default actions.

Delete—Deletes an IP audit policy. You cannot delete a default action.

Policy-to-Interface Mappings—Assigns an attack and informational policy to each interface.

–

–

–

Interface—Shows the interface name.

Attack Policy—Lists the attack audit policy names available. Assign a policy to an interface by clicking the name in the list.

Info Policy—Lists the informational audit policy names available. Assign a policy to an interface by clicking the name in the list.

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Add/Edit IP Audit Policy Configuration

The Configuration > Properties > IP Audit > IP Audit Policy > Add/Edit IP Audit Policy Configuration dialog box lets you add or edit a named IP audit policy that you can assign to interfaces, and lets you modify the default actions for each signature type.

Fields

•

Policy Name—Sets the IP audit policy name. You cannot edit the name after you add it.

•

Policy Type—Sets the policy type. You cannot edit the policy type after you add it.

•

–

–

Attack—Sets the policy type as attack.

Information—Sets the policy type as informational.

Action—Sets one or more actions to take when a packet matches a signature. If you do not choose an action, then the default policy is used.

–

Alarm—Generates a system message showing that a packet matched a signature. For a complete list of signatures, see

IP Audit Signature List .

–

–

Drop—Drops the packet.

Reset—Drops the packet and closes the connection.

IP Audit Signatures

The Configuration > Properties > IP Audit > IP Audit Signatures pane lets you disable audit signatures.

You might want to disable a signature if legitimate traffic continually matches a signature, and you are willing to risk disabling the signature to avoid large numbers of alarms.

For a complete list of signatures, see the

“IP Audit Signature List” section on page 52-7

.

Fields

•

Enabled—Lists the enabled signatures.

•

•

•

Disabled—Lists the disabled signatures.

Disable—Moves the selected signature to the Disabled pane.

Enable—Moves the selected signature to the Enabled pane.

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IP Audit Signature List

Table 52-1

Table 52-1

lists supported signatures and system message numbers.

Signature IDs and System Message Numbers

Signature

ID

1000

Message

Number Signature Title

400000 IP options-Bad Option List

1001

1002

1003

1004

1005

1006

1100

1102

400001 IP options-Record Packet Route

400002 IP options-Timestamp

400003 IP options-Security

400004 IP options-Loose Source Route

400005 IP options-SATNET ID

400006 IP options-Strict Source Route

400007 IP Fragment Attack

400008 IP Impossible Packet

Signature Type Description

Informational Triggers on receipt of an IP datagram where the list of IP options in the IP datagram header is incomplete or malformed. The IP options list contains one or more options that perform various network management or debugging tasks.

Informational Triggers on receipt of an IP datagram where the IP option list for the datagram includes option 7 (Record Packet Route).

Informational Triggers on receipt of an IP datagram where the IP option list for the datagram includes option 4 (Timestamp).

Informational Triggers on receipt of an IP datagram where the IP option list for the datagram includes option 2 (Security options).

Informational Triggers on receipt of an IP datagram where the IP option list for the datagram includes option 3 (Loose Source Route).

Informational Triggers on receipt of an IP datagram where the IP option list for the datagram includes option 8 (SATNET stream identifier).

Informational Triggers on receipt of an IP datagram in which the IP option list for the datagram includes option 2 (Strict Source Routing).

Attack

Attack

Triggers when any IP datagram is received with an offset value less than 5 but greater than 0 indicated in the offset field.

Triggers when an IP packet arrives with source equal to destination address. This signature will catch the so-called Land

Attack.

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Table 52-1 Signature IDs and System Message Numbers (continued)

Signature

ID

1103

2000

2001

Message

Number Signature Title Signature Type Description

400009 IP Overlapping Fragments (Teardrop) Attack Triggers when two fragments contained within the same IP datagram have offsets that indicate that they share positioning within the datagram. This could mean that fragment A is being completely overwritten by fragment B, or that fragment A is partially being overwritten by fragment B. Some operating systems do not properly handle fragments that overlap in this manner and may throw exceptions or behave in other undesirable ways upon receipt of overlapping fragments, which is how the Teardrop attack works to create a DoS.

400010 ICMP Echo Reply

400011 ICMP Host Unreachable

Informational Triggers when a IP datagram is received with the protocol field of the IP header set to 1

(ICMP) and the type field in the ICMP header set to 0 (Echo Reply).

Informational Triggers when an IP datagram is received with the protocol field of the IP header set to

1 (ICMP) and the type field in the ICMP header set to 3 (Host Unreachable).

2002

2003

2004

2005

2006

2007

400012

400013

ICMP Source Quench

ICMP Redirect

Informational Triggers when an IP datagram is received with the protocol field of the IP header set to

1 (ICMP) and the type field in the ICMP header set to 4 (Source Quench).


(ICMP) and the type field in the ICMP header set to 5 (Redirect).

400014 ICMP Echo Request

400015 ICMP Time Exceeded for a Datagram Informational Triggers when a IP datagram is received with the protocol field of the IP header set to 1

(ICMP) and the type field in the ICMP header set to 11(Time Exceeded for a Datagram).

400016 ICMP Parameter Problem on

Datagram


(ICMP) and the type field in the ICMP header set to 8 (Echo Request).

400017 ICMP Timestamp Request


(ICMP) and the type field in the ICMP header set to 12 (Parameter Problem on Datagram).


(ICMP) and the type field in the ICMP header set to 13 (Timestamp Request).

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Table 52-1

Signature

ID

2008

Message

Number Signature Title

400018 ICMP Timestamp Reply

2009

2010

2011

2012

2150

2151

2154

3040

3041

Signature IDs and System Message Numbers (continued)

400019

400020

400021

400022

400023

400024

400025

400026

400027

ICMP Information Request

ICMP Information Reply

ICMP Address Mask Request

ICMP Address Mask Reply

Fragmented ICMP Traffic

Large ICMP Traffic

Ping of Death Attack

TCP NULL flags

TCP SYN+FIN flags



(ICMP) and the type field in the ICMP header set to 14 (Timestamp Reply).


(ICMP) and the type field in the ICMP header set to 15 (Information Request).


(ICMP) and the type field in the ICMP header set to 16 (ICMP Information Reply).


(ICMP) and the type field in the ICMP header set to 17 (Address Mask Request).


(ICMP) and the type field in the ICMP header set to 18 (Address Mask Reply).

Attack

Attack

Triggers when a IP datagram is received with the protocol field of the IP header set to 1

(ICMP) and either the more fragments flag is set to 1 (ICMP) or there is an offset indicated in the offset field.

Triggers when a IP datagram is received with the protocol field of the IP header set to

1(ICMP) and the IP length > 1024.

Attack

Attack

Attack

Triggers when a IP datagram is received with the protocol field of the IP header set to

1(ICMP), the Last Fragment bit is set, and (IP offset * 8) + (IP data length) > 65535 that is to say, the IP offset (which represents the starting position of this fragment in the original packet, and which is in 8 byte units) plus the rest of the packet is greater than the maximum size for an IP packet.

Triggers when a single TCP packet with none of the SYN, FIN, ACK, or RST flags set has been sent to a specific host.

Triggers when a single TCP packet with the

SYN and FIN flags are set and is sent to a specific host.

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Signature

ID

3042

3153

3154

4050

4051

4052

6050

6051

6052

6053

6100

6101

6102

6103

6150

6151

Message

Number

400028

400029

400030

400031

400032

400033

400034

Signature Title

TCP FIN only flags

FTP Improper Address Specified

FTP Improper Port Specified

UDP Bomb attack

UDP Snork attack

UDP Chargen DoS attack

DNS HINFO Request


Attack Triggers when a single orphaned TCP FIN packet is sent to a privileged port (having port number less than 1024) on a specific host.

Informational Triggers if a port command is issued with an address that is not the same as the requesting host.

Informational Triggers if a port command is issued with a data port specified that is <1024 or >65535.

Attack

Attack

Triggers when the UDP length specified is less than the IP length specified. This malformed packet type is associated with a denial of service attempt.

Triggers when a UDP packet with a source port of either 135, 7, or 19 and a destination port of 135 is detected.

Attack This signature triggers when a UDP packet is detected with a source port of 7 and a destination port of 19.

Informational Triggers on an attempt to access HINFO records from a DNS server.

400035 DNS Zone Transfer Informational Triggers on normal DNS zone transfers, in which the source port is 53.

400036 DNS Zone Transfer from High Port Informational Triggers on an illegitimate DNS zone transfer, in which the source port is not equal to 53.

400037 DNS Request for All Records

400038 RPC Port Registration

Informational Triggers on a DNS request for all records.

Informational Triggers when attempts are made to register new RPC services on a target host.

400039 RPC Port Unregistration

400040

400041

400042

400043

RPC Dump

Proxied RPC Request ypserv (YP server daemon) Portmap

Request ypbind (YP bind daemon) Portmap

Request

Informational Triggers when attempts are made to unregister existing RPC services on a target host.

Informational Triggers when an RPC dump request is issued to a target host.

Attack Triggers when a proxied RPC request is sent to the portmapper of a target host.

Informational Triggers when a request is made to the portmapper for the YP server daemon

(ypserv) port.

Informational Triggers when a request is made to the portmapper for the YP bind daemon (ypbind) port.

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Signature

ID

6152

6153

6154

6155

6175

6180

6190

Message

Number

400044

400045

Signature Title

yppasswdd (YP password daemon)

Portmap Request

400046 ypxfrd (YP transfer daemon) Portmap

Request

400047

400048

400049

400050 ypupdated (YP update daemon)

Portmap Request mountd (mount daemon) Portmap

Request rexd (remote execution daemon)

Portmap Request rexd (remote execution daemon)

Attempt statd Buffer Overflow


Informational Triggers when a request is made to the portmapper for the YP password daemon

(yppasswdd) port.

Informational Triggers when a request is made to the portmapper for the YP update daemon

(ypupdated) port.

Informational Triggers when a request is made to the portmapper for the YP transfer daemon

(ypxfrd) port.

Informational Triggers when a request is made to the portmapper for the mount daemon (mountd) port.

Informational Triggers when a request is made to the portmapper for the remote execution daemon

(rexd) port.

Informational Triggers when a call to the rexd program is made. The remote execution daemon is the server responsible for remote program execution. This may be indicative of an attempt to gain unauthorized access to system resources.

Attack Triggers when a large statd request is sent.

This could be an attempt to overflow a buffer and gain access to system resources.

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P

A R T

1 2

Configuring Applications on SSMs and

SSCs

C H A P T E R

53

Managing SSMs and SSCs

This chapter describes how to manage a Security Services Card (SSC) or a Security Services Module

(SSM) that is installed in the adaptive security appliance. The SSM and SSC run advanced security applications, such as IPS and Content Security and Control.

Note

For information about the 4GE SSM, which is an interface module and does not run intelligent software, see

Chapter 8, “Configuring Interfaces.”


•

Information About SSMs and SSCs, page 53-1

•

•

•

•

•



Configuring the SSC Management Interface, page 53-4


Feature History for the SSM and SSC, page 53-7

Information About SSMs and SSCs

This section describes SSMs and SSCs and includes the following topics:

•

Supported Applications, page 53-1

•

Information About Management Access, page 53-2

Supported Applications

The following applications are supported on the SSM:

•

•

IPS software (on the AIP SSM)

Content Security and Control software (on the CSC SSM)

The following applications are supported on the SSC:

•

IPS software (on the AIP SSC)


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Chapter 53 Managing SSMs and SSCs

Information About SSMs and SSCs

Note

You cannot change the software type installed on the SSM/SSC; if you purchase an AIP SSM, you cannot later install CSC software on it.

Information About Management Access

You can manage the module application using ASDM or by using the module application CLI. This section includes the following topics:

•

•

•

Sessioning to the Module, page 53-2

Using ASDM, page 53-2

•

•

Using SSH or Telnet, page 53-3

Other Uses for the Module Management Interface, page 53-3

Routing Considerations for Accessing the Management Interface, page 53-3

Sessioning to the Module

If you have CLI access to the adaptive security appliance, then you can session to the module over the backplane and access the module CLI.

Using ASDM

After you launch ASDM on the adaptive security appliance, ASDM connects to the SSM or SSC management interface to configure the module application.

On the SSM, ASDM connects to an external Gigabit Ethernet port. If you cannot use the default address, you can change the interface IP address and other network parameters by sessioning to the module and setting the parameters at the module CLI. See the documentation for the module application for more information.

On the SSC, you can configure a VLAN as a management VLAN to allow access to an internal management IP address over the backplane. To change the network parameters, see the

“Configuring the

SSC Management Interface” section on page 53-4 .

See the

“Default Settings” section on page 53-4 for information about the default management interface

parameters.

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Using SSH or Telnet

You can access the module CLI directly using SSH or Telnet to the module management interface.

(Telnet access requires additional configuration in the SSM/SSC application). See the “Using ASDM” section on page 53-2 for more information about the management interface.

Other Uses for the Module Management Interface

The module management interface can be used for sending syslog messages or allowing updates for the module application, such as signature database updates on the AIP SSM or SSC.

Routing Considerations for Accessing the Management Interface

To make sure ASDM can manage the SSC, be sure that the adaptive security appliance can access the module management interface address.

For the SSC, be sure to configure an IP address for the adaptive security appliance VLAN that you are also using for the SSC management interface, and assign that VLAN to a switch port so the SSC interface is physically connected to the network. The SSC management interface will then be on a directly-connected network for the adaptive security appliance, so ASDM can access the management interface without any additional routing configuration.

For the SSM, the external management interface is not considered to be an adaptive security appliance interface, so it is not automatically on a directly-connected network. Depending on how you cable your network, the SSM external interface can be on the same network as an adaptive security appliance interface (through a switch), or you can put it on a different network (through a router).



See the chapter for each SSM or SSC application for context mode guidelines.


See the chapter for each SSM or SSC application for firewall mode guidelines.


For the SSC, make sure you configure the management IP addresses on both units to be on the same subnet and VLAN.


For model support for the SSC and SSMs, see the

“Module Support” section on page 1-2 .


You cannot change the software type installed on the SSM/SSC; if you purchase an AIP SSM, you cannot later install CSC software on it.

You cannot set up the SSC in ASDM if you use an IP address that goes through NAT.

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Table 53-1 lists the default network settings for SSMs and SSCs.

Table 53-1 Default Network Parameters

Parameters

Management VLAN (SSC only)

Management IP address

Management hosts (SSC only)

Gateway

Default

VLAN 1

192.168.1.2/24

192.168.1.0/24

192.168.1.1


Note

The default management IP address on the adaptive security appliance is 192.168.1.1/24.

Configuring the SSC Management Interface

An SSC does not have any external interfaces. You can configure a VLAN as a management VLAN to allow access to an internal management IP address over the backplane. By default, VLAN 1 is enabled for the SSC management address. You can only assign one VLAN as the SSC management VLAN. This section describes how to change the management VLAN. It also describes how to change the default

management IP address, allowed hosts, and gateway. See the “Default Settings” section on page 53-4 for

more information about defaults.

Prerequisites

For the VLAN you want to use for the SSC management interface, configure the switch port and VLAN

interface on the ASA 5505 according to the procedures listed in Chapter 8, “Starting Interface

Configuration (ASA 5505).” This configuration is required so the SSC interface is physically connected

to the network.

Restrictions

Do not configure NAT for the management address if you intend to access it using ASDM. For initial setup with ASDM, you need to access the real address. After initial setup (where you set the password in the SSC), you can configure NAT and supply ASDM with the translated address when you want to access the SSC.

Detailed Steps

Step 1

If you are configuring the SSC for the first time, in the ASDM main window, choose

Configuration >

Device Setup > SSC Setup

.

Note

If you click the

IPS

tab before you have configured the SSC, the Stop dialog box appears. Click

OK

to have ASDM redirect you to the SSC Setup pane. You must define the settings in the SSC

Setup pane before you can access any part of the GUI.

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Step 2

In the Management Interface area, do the following:

a.

Choose the Interface VLAN from the drop-down list.

This setting allows you to manage the SSC using this VLAN.

Note

The following settings are written to the SSC application configuration, not the adaptive security appliance configuration.

Step 3 b.

c.

d.

Enter the IP address.

Choose the subnet mask from the drop-down list.

Enter the default gateway IP address.

If the management station is on a directly-connected adaptive security appliance network, then set the gateway to be the ASA 5505 VLAN interface address. If the management station is on a remote network, then set the gateway to the address of an upstream router on the management VLAN.

In the Management Access List area, do the following.

Note


a.

b.

c.

Enter the IP address for the host network.

Choose the subnet mask from the drop-down list.

Click

Add

to add these settings to the Allowed Hosts/Networks list.

Note

After you click

Add

, make sure you save the management settings you have just defined by clicking

Apply

. If you decide to remove these settings, continue to the next substep.

Otherwise, go to

Step 4 .

Step 4 d.

To delete these settings, in the ASDM main window, click the

IPS

tab. Choose

Configuration > IPS

> Sensor Setup > Allowed Hosts/Networks

. Choose the host or network that you want to remove from the list, and click

Delete

. To add new management settings, you can either click

Add

in the existing pane or return to the SSC Setup pane by choosing

Configuration > Device Setup > SSC

Setup

.

In the IPS Password area, do the following:

Note


Step 5

Step 6 a.

Enter the password. The default password is “cisco.”

b.

Enter the new password, and confirm the change.

Click

Apply

to save the settings to the running configuration.

The SSC Setup completed dialog box appears only after the initial configuration.

To complete the SSC application configuration and have ASDM go directly to the Configuration > IPS

> Sensor Setup > Startup Wizard screen, do one of the following:

•

Click the

IPS

button in the navigation pane.


OL-20339-01 53-5



•

Click the

Configure the IPS SSC module

link.

Note

If you want to change the SSC configuration settings at a later date, click the

IPS

tab.

Password Troubleshooting

You can reset the SSM/SSC password to the default; for IPS, password reset is supported if the SSM/SSC is running IPS Version 6.0 or later. The default password is “cisco” (without the quotation marks). After resetting the password, you should change it to a unique value using the SSM/SSC application.

Resetting the SSM/SSC password causes the SSM/SSC to reboot. Services are not available while the

SSM/SSC is rebooting.

After you log in and define a new password, you do not need to log in to the software again. If you cannot connect to the software with the new password, restart ASDM and try to log in again.

If you defined a new password and still have an existing password that is different from the new password, clear the password cache by choosing

File > Clear ASDM Password Cache

, then restart

ASDM and try to log in again.

Detailed Steps

Step 1

Step 2

Step 3

From the ASDM menu bar, choose

Tools > IPS Password Reset

or

Tools > CSC Password Reset

.

The IPS/CSC Password Reset confirmation dialog box appears.

Click

OK

to reset the password to the default.

A dialog box displays the success or failure of the password reset.For IPS, if the password was not reset, make sure you are using IPS Version 6.0 or later on the AIP SSM/SSC.

Click

Close

to close the dialog box.

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To configure the AIP SSM or SSC, see

Chapter 54, “Configuring the IPS Application on the

AIP SSM and SSC.”

To configure the CSC SSM, see

Chapter 55, “Configuring the Content Security and Control Application on the CSC SSM.”

Feature History for the SSM and SSC

Table 53-2


Table 53-2

Feature Name

SSM

Feature History for the SSM and SSC

Platform

Releases Feature Information

ASA 7.0(1) SSMs were introduced to support multiple applications.

Password reset

SSC

ASA 7.2(2) The

Tools > IPS/CSC Password Reset


ASA 8.2(1) The SSC was introduced for the ASA 5505.

The

Configuration > Device Setup > SSC Setup


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C H A P T E R

54

Configuring the IPS Application on the

AIP SSM and SSC

This chapter describes how to configure the IPS application that runs on an Advanced Inspection and

Prevention Security Services Module (AIP SSM) or an Advanced Inspection and Prevention Security

Security Services Card (AIP SSC).

Note

The SSC is supported on the ASA 5505. See the “Module Support” section on page 1-2

for more information about which models support SSMs.


•

•

Information About the AIP SSM and SSC, page 54-1

Licensing Requirements for the AIP SSM/SSC, page 54-4

•

•

•

•


Configuring the AIP SSM/SSC, page 54-5

Feature History for the AIP SSM/SSC, page 54-9

Feature History for the AIP SSM/SSC, page 54-9

Information About the AIP SSM and SSC

You can install the AIP SSM/SSC into an ASA 5500 series adaptive security appliance. The AIP

SSM/SSC runs advanced IPS software that provides proactive, full-featured intrusion prevention services to stop malicious traffic, including worms and network viruses, before they can affect your network. This section includes the following topics:

•

•

How the AIP SSM/SSC Works with the Adaptive Security Appliance, page 54-2

Operating Modes, page 54-2

•

•

Using Virtual Sensors (AIP SSM Only), page 54-3

Differences Between the AIP SSM and the AIP SSC, page 54-4


54-1 OL-20339-01

Chapter 54 Configuring the IPS Application on the AIP SSM and SSC


How the AIP SSM/SSC Works with the Adaptive Security Appliance

The AIP SSM/SSC runs a separate application from the adaptive security appliance. The AIP SSM/SSC does not contain any external interfaces itself (except for the management interface on the SSM only).

Traffic goes through the firewall checks before being forwarded to the AIP SSM/SSC. When you identify traffic for IPS inspection on the adaptive security appliance, traffic flows through the adaptive security appliance and the AIP SSM/SSC in the following way:

a.

Traffic enters the adaptive security appliance.

b.

Firewall policies are applied.

c.

Traffic is sent to the AIP SSM/SSC over the backplane.

See the

“Operating Modes” section on page 54-2

for information about only sending a copy of the traffic to the AIP SSM/SSC.

d.

The AIP SSM/SSC applies its security policy to the traffic, and takes appropriate actions.

e.

Valid traffic is sent back to the adaptive security appliance over the backplane; the AIP

SSM/SSC might block some traffic according to its security policy, and that traffic is not passed on.

f.

VPN policies are applied (if configured).

g.

Traffic exits the adaptive security appliance.

Figure 54-1

shows the traffic flow when running the AIP SSM/SSC. In this example, the AIP

SSM/SSC automatically blocks traffic that it identified as an attack. All other traffic is forwarded through the adaptive security appliance.

Figure 54-1 AIP SSM/SSC Traffic Flow in the Adaptive Security Appliance

inside


Main System

VPN

Policy

Firewall

Policy outside

Diverted Traffic

Backplane

Block

IPS inspection

AIP SSM/SSC

Operating Modes

You can send traffic to the AIP SSM/SSC using one of the following modes:

•

Inline mode—This mode places the AIP SSM/SSC directly in the traffic flow (see

Figure 54-1

). No traffic that you identified for IPS inspection can continue through the adaptive adaptive security appliance without first passing through, and being inspected by, the AIP SSM/SSC. This mode is the

54-2


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•

most secure because every packet that you identify for inspection is analyzed before being allowed through. Also, the AIP SSM/SSC can implement a blocking policy on a packet-by-packet basis. This mode, however, can affect throughput.

Promiscuous mode—This mode sends a duplicate stream of traffic to the AIP SSM/SSC. This mode is less secure, but has little impact on traffic throughput. Unlike the inline mode, in promiscuous mode the AIP SSM/SSC can only block traffic by instructing the adaptive adaptive security appliance to shun the traffic or by resetting a connection on the adaptive adaptive security appliance.

Also, while the AIP SSM/SSC is analyzing the traffic, a small amount of traffic might pass through

the adaptive adaptive security appliance before the AIP SSM/SSC can shun it. Figure 54-2

shows the AIP SSM/SSC in promiscuous mode. In this example, the AIP SSM/SSC sends a shun message to the adaptive security appliance for traffic it identified as a threat.

Figure 54-2 AIP SSM/SSC Traffic Flow in the Adaptive Security Appliance: Promiscuous Mode

inside


Main System

VPN

Policy

Shun message

Firewall

Policy

Copied Traffic outside

Backplane

IPS inspection

AIP SSM/SSC

Using Virtual Sensors (AIP SSM Only)

The AIP SSM running IPS software Version 6.0 and above can run multiple virtual sensors, which means you can configure multiple security policies on the AIP SSM. You can assign each context or single mode adaptive security appliance to one or more virtual sensors, or you can assign multiple security contexts to the same virtual sensor. See the IPS documentation for more information about virtual sensors, including the maximum number of sensors supported.

Figure 54-3 shows one security context paired with one virtual sensor (in inline mode), while two

security contexts share the same virtual sensor.

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54-3


Licensing Requirements for the AIP SSM/SSC

Figure 54-3 Security Contexts and Virtual Sensors

Context

1


Main System

Context

2

Context

3

Sensor

1

AIP SSM/SSC

Sensor

2

Figure 54-4

shows a single mode adaptive security appliance paired with multiple virtual sensors (in inline mode); each defined traffic flow goes to a different sensor.

Figure 54-4 Single Mode Security Appliance with Multiple Virtual Sensors


Main System

Traffic 1

Traffic 2

Traffic 3

Sensor

1

AIP SSM/SSC

Sensor

2

Sensor

3

Differences Between the AIP SSM and the AIP SSC

The AIP SSM supports the higher performance requirements of the ASA 5510 and above, while the

AIP SSC is designed for the small office installation of the ASA 5505 adaptive security appliance. The following features are supported on the AIP SSM, but not on the AIP SSC:

•

Virtual sensors

•

•

Anomaly detection

Unretirement of default retired signatures

Licensing Requirements for the AIP SSM/SSC


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Model

All models


Base License.

The IPS application on the AIP SSM/SSC requires a separate Cisco Services for IPS license in order to support signature updates. All other updates are available without a license.




The ASA 5505 adaptive security appliance does not support multiple context mode, so multiple context features, such as virtual sensors, are not supported on the AIP SSC.




•

The SSC is supported on the ASA 5505 only. See the more information about which models support SSMs.

“Module Support” section on page 1-2

for

•

The ASA 5505 adaptive security appliance does not support multiple context mode, so multiple context features, such as virtual sensors, are not supported on the AIP SSC.

Configuring the AIP SSM/SSC

This section describes how to configure IPS for the AIP SSM and AIP SSC and includes the following topics:

•

•

AIP SSM/SSC Task Overview, page 54-5

Configuring the Security Policy on the AIP SSM/SSC, page 54-6

•

•

Assigning Virtual Sensors to a Security Context (AIP SSM Only), page 54-7

Diverting Traffic to the AIP SSM/SSC, page 54-8

AIP SSM/SSC Task Overview

Configuring the AIP SSM/SSC is a process that includes configuration of the IPS software on the

SSM/SSC and then configuration of the ASA 5500 series adaptive security appliance. To configure the

AIP SSM/SSC, perform the following steps:

Step 1

On the AIP SSM/SSC, configure the inspection and protection policy, which determines how to inspect traffic and what to do when an intrusion is detected. For the AIP SSM only, configure the inspection and protection policy for each virtual sensor if you want to run the AIP SSM in multiple sensor mode. See the

“Configuring the Security Policy on the AIP SSM/SSC” section on page 54-6 .

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Step 2

Step 3

(AIP SSM only) On the ASA 5500 in multiple context mode, specify which IPS virtual sensors are available for each context (if you configured virtual sensors). See the

“Assigning Virtual Sensors to a

Security Context (AIP SSM Only)” section on page 54-7 .

On the ASA 5500, identify traffic to divert to the AIP SSM/SSC. See the

“Diverting Traffic to the AIP

SSM/SSC” section on page 54-8 .

Configuring the Security Policy on the AIP SSM/SSC

This section describes how to access the IPS application in the AIP SSM/SSC.

Detailed Steps

Note

See also the

“Configuring the SSC Management Interface” section on page 53-4

to configure the SSC management interface for ASDM access and other uses.

Step 1

Step 2

Step 3

To access IDM from ASDM, click

Configuration > IPS

.

You are asked for the IP address or hostname of the AIP SSM/SSC.

•

If the AIP SSM/SSC is running IPS Version 6.0 or later, ASDM retrieves IDM from the AIP

SSM/SSC and displays it as part of the ASDM interface. Enter the AIP SSM/SSC password and click

OK

.

The IDM panes appear in the ASDM window.

•

For the AIP SSM only, if it is running an earlier version of IPS software, ASDM displays a link to

IDM. Click the link to launch IDM in a new browser window. You need to provide a username and password to access IDM.

If the password to access IDM is lost, you can reset the password using ASDM. See the

“Password

Troubleshooting” section on page 53-6 , for more information.

Configure the IPS security policy.

For the AIP SSM only, if you configure virtual sensors in IPS Version 6.0 or above, you identify one of the sensors as the default. If the ASA 5500 series adaptive adaptive security appliance does not specify a virtual sensor name in its configuration, the default sensor is used.

Because the IPS software that runs on the AIP SSM/SSC is beyond the scope of this document, detailed configuration information is available in the IPS documents at the following location: http://www.cisco.com/en/US/products/hw/vpndevc/ps4077/tsd_products_support_series_home.html

What to Do Next

•

•

For the adaptive security appliance in multiple context mode, see the

“Assigning Virtual Sensors to a Security Context (AIP SSM Only)” section on page 54-7 .

For the adaptive security appliance in single context mode, see the



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Assigning Virtual Sensors to a Security Context (AIP SSM Only)

If the adaptive security appliance is in multiple context mode, then you can assign one or more IPS virtual sensors to each context. Then, when you configure the context to send traffic to the AIP SSM, you can specify a sensor that is assigned to the context; you cannot specify a sensor that you did not assign to the context. If you do not assign any sensors to a context, then the default sensor configured on the AIP SSM is used. You can assign the same sensor to multiple contexts.

Prerequisites

Note

You do not need to be in multiple context mode to use virtual sensors; you can be in single mode and use different sensors for different traffic flows.

For more information about configuring contexts, see the

“Configuring a Security Context” section on page 6-17

.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

In the ASDM Device List pane, double-click

System


On the Context Management > Security Contexts pane, choose a context that you want to configure, and click

Edit

.

The Edit Context dialog box appears. For more information about configuring contexts, see the

“Configuring a Security Context” section on page 6-17 .

In the IPS Sensor Allocation area, click

Add

.

The IPS Sensor Selection dialog box appears.

From the Sensor Name drop-down list, choose a sensor name from those configured on the AIP SSM.

(Optional) To assign a mapped name to the sensor, enter a value in the Mapped Sensor Name field.

This sensor name can be used within the context instead of the actual sensor name. If you do not specify a mapped name, the sensor name is used within the context. For security purposes, you might not want the context administrator to know which sensors are being used by the context. Or you might want to genericize the context configuration. For example, if you want all contexts to use sensors called

“sensor1” and “sensor2,” then you can map the “highsec” and “lowsec” sensors to sensor1 and sensor2 in context A, but map the “medsec” and “lowsec” sensors to sensor1 and sensor2 in context B.

Click

OK

to return to the Edit Context dialog box.

(Optional) To set one sensor as the default sensor for this context, from the Default Sensor drop-down list, choose a sensor name.

If you do not specify a sensor name when you configure IPS within the context configuration, the context uses this default sensor. You can only configure one default sensor per context. If you do not specify a sensor as the default, and the context configuration does not include a sensor name, then traffic uses the default sensor on the AIP SSM.

Repeat this procedure for each security context.

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Step 9

Change to each context to configure the IPS security policy as described in



What to Do Next

Change to each context to configure the IPS security policy as described in



Diverting Traffic to the AIP SSM/SSC

This section identifies traffic to divert from the adaptive adaptive security appliance to the AIP

SSM/SSC.

Prerequisites

In multiple context mode, perform these steps in each context execution space.

Detailed Steps

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

In the ASDM Device List pane, double-click the context name under the active device

IP address

>

Contexts.

Click


.

You can edit an existing rule or create a new one:

•

For an existing rule, choose the rule and click

Edit

The Edit Service Policy Rule dialog box appears.

.

•

For a new rule, choose

Add > Add Service Policy Rule

.

The Add Service Policy Rule Wizard - Service Policy dialog box appears. Complete the Service

Policy and Traffic Classification Criteria dialog boxes. See the

“Adding a Service Policy Rule for

Through Traffic” section on page 29-8

for more information. Click

Next

to show the Add Service

Policy Rule Wizard - Rule Actions dialog box.

Click the

Intrusion Prevention

tab.

You can also set other feature actions for the same traffic using the other tabs.

Check the

Enable IPS for this traffic flow

check box.

In the Mode area, click

Inline Mode

or

Promiscuous Mode

.

See the

“Operating Modes” section on page 54-2 for more details.

In the If IPS Card Fails area, click

Permit traffic

or

Close traffic

.

The Close traffic option sets the adaptive security appliance to block all traffic if the AIP SSM/SSC is unavailable.

The Permit traffic option sets the adaptive security appliance to allow all traffic through, uninspected, if the AIP SSM/SSC is unavailable.

(AIP SSM Only) From the IPS Sensor to use drop-down list, choose a virtual sensor name.

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Feature History for the AIP SSM/SSC

Step 9

If you use virtual sensors on the AIP SSM only, you can specify a sensor name using this option. If you use multiple context mode on the adaptive security appliance, you can only specify sensors that you assigned to the context (see the

“Assigning Virtual Sensors to a Security Context (AIP SSM Only)” section on page 54-7 ). If you do not specify a sensor name, then the traffic uses the default sensor. In

multiple context mode, you can specify a default sensor for the context. In single mode or if you do not specify a default sensor in multiple mode, the traffic uses the default sensor that is set on the AIP SSM.

Click

OK

.


Table 54-1


Table 54-1

Feature Name

AIP SSM

Feature History for the AIP SSM/SSC

Platform

Releases

7.0(1)

Virtual sensors

AIP SSC for the ASA 5505

8.0(2)

8.2(1)


The AIP SSM was introduced.


Firewall > Service Policy Rules > Add/Edit Service Policy

Rule > Intrusion Prevention.

Virtual sensor support was introduced. Virtual sensors let you configure multiple security policies on the AIP SSM.

The following screen was modified: Context Management >

Security Contexts > Edit Context.

The AIP SSC was introduced.


Device Setup > SSC Setup.

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C H A P T E R

55

Configuring the Content Security and Control

Application on the CSC SSM

This chapter describes how to configure the Content Security and Control (CSC) application that is installed in a CSC SSM in the adaptive security appliance.


•

Information About the CSC SSM, page 55-1

•

•

•

•

Licensing Requirements for the CSC SSM, page 55-5

Prerequisites for the CSC SSM, page 55-5



•

•

•

•

•

Configuring the CSC SSM, page 55-7

Monitoring the CSC SSM, page 55-10



Feature History for the CSC SSM, page 55-15

Information About the CSC SSM

Note

The ASA 5580 does not support the CSC SSM feature.

The ASA 5500 series adaptive security appliance supports the CSC SSM, which runs Content Security and Control software. The CSC SSM provides protection against viruses, spyware, spam, and other unwanted traffic by scanning the FTP, HTTP, POP3, and SMTP packets that you configure the adaptive security appliance to send to it.

For more information about the CSC SSM, see the following URL: http://www.cisco.com/en/US/products/ps6823/index.html

Figure 55-1 shows the flow of traffic through an adaptive security appliance that has the following:

•

A CSC SSM installed and configured.

•

A service policy that determines what traffic is diverted to the CSC SSM for scanning.

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55-1

Chapter 55 Configuring the Content Security and Control Application on the CSC SSM


In this example, the client could be a network user who is accessing a website, downloading files from an FTP server, or retrieving mail from a POP3 server. SMTP scans differ in that you should configure the adaptive security appliance to scan traffic sent from the outside to SMTP servers protected by the adaptive security appliance.

Figure 55-1 Flow of Scanned Traffic with CSC SSM

Client

Request sent inside

Reply forwarded

Adaptive


Main System

modular service policy

Diverted Traffic

Request forwarded outside

Reply sent

Server content security scan

CSC SSM

You use ASDM for system setup and monitoring of the CSC SSM. For advanced configuration of content security policies in the CSC SSM software, you access the web-based GUI for the CSC SSM by clicking links within ASDM. The CSC SSM GUI appears in a separate web browser window. To access the CSC

SSM, you must enter the CSC SSM password. To use the CSC SSM GUI, see the

Cisco Content Security and Control (CSC) SSM Administrator Guide

.

Note

ASDM and the CSC SSM maintain separate passwords. You can configure their passwords to be identical; however, changing one of these two passwords does not affect the other password.

The connection between the host running ASDM and the adaptive security appliance is made through a management port on the adaptive security appliance. The connection to the CSC SSM GUI is made through the SSM management port. Because these two connections are required to manage the CSC

SSM, any host running ASDM must be able to reach the IP address of both the adaptive security appliance management port and the SSM management port.

Figure 55-2

shows an adaptive security appliance with a CSC SSM that is connected to a dedicated management network. While use of a dedicated management network is not required, we recommend it.

In this configuration, the following items are of particular interest:

•

An HTTP proxy server is connected to the inside network and to the management network. This

HTTP proxy server enables the CSC SSM to contact the Trend Micro Systems update server.

•

•

The management port of the adaptive security appliance is connected to the management network.

To allow management of the adaptive security appliance and the CSC SSM, hosts running ASDM must be connected to the management network.

The management network includes an SMTP server for e-mail notifications for the CSC SSM and a syslog server to which the CSC SSM can send syslog messages.

55-2


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Figure 55-2

HTTP

Proxy


CSC SSM Deployment with a Management Network

Adaptive Security

Appliance

inside

192.168.100.1

Main System

management port

192.168.50.1

outside

10.6.13.67

Internet

Trend Micro

Update Server

ASDM

CSC SSM

192.168.50.38 SSM management port

Syslog

Notifications

SMTP Server

Determining What Traffic to Scan

The CSC SSM can scan FTP, HTTP, POP3, and SMTP traffic only when the destination port of the packet requesting the connection is the well-known port for the specified protocol. The CSC SSM can scan only the following connections:

•

•

•

FTP connections opened to TCP port 21.

HTTP connections opened to TCP port 80.

POP3 connections opened to TCP port 110.

•

SMTP connections opened to TCP port 25.

You can choose to scan traffic for all of these protocols or any combination of them. For example, if you do not allow network users to receive POP3 e-mail, do not configure the adaptive security appliance to divert POP3 traffic to the CSC SSM. Instead, block this traffic.

To maximize performance of the adaptive security appliance and the CSC SSM, divert only the traffic to the CSC SSM that you want the CSC SSM to scan. Diverting traffic that you do not want scanned, such as traffic between a trusted source and destination, can adversely affect network performance.

Note

When traffic is first classified for CSC inspection, it is flow-based. If traffic is part of a pre-existing connection, the traffic goes directly to the service policy set for that connection.

You can apply service policies that include CSC scanning globally or to specific interfaces; therefore, you can choose to enable CSC scans globally or for specific interfaces. For more information, see the

“Determining Service Policy Rule Actions for CSC Scanning” section on page 55-9 .

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55-3



Based on the configuration shown in

Figure 55-3

, configure the adaptive security appliance to divert to the CSC SSM only requests from clients on the inside network for HTTP, FTP, and POP3 connections to the outside network, and incoming SMTP connections from outside hosts to the mail server on the

DMZ network. Exclude from scanning HTTP requests from the inside network to the web server on the

DMZ network.

Figure 55-3 Common Network Configuration for CSC SSM Scanning

192.168.10.0

Adaptive Security

Appliance

inside outside

192.168.30.0

192.168.20.0

(dmz)

Internet

Web server Mail server

There are many ways you could configure the adaptive security appliance to identify the traffic that you want to scan. One approach is to define two service policies: one on the inside interface and the other on the outside interface, each with access lists that match traffic to be scanned.

Figure 55-4

shows service policy rules that select only the traffic that the adaptive security appliance should scan.

Figure 55-4 Optimized Traffic Selection for CSC Scans

In the inside-policy, the first class, inside-class1, ensures that the adaptive security appliance does not scan HTTP traffic between the inside network and the DMZ network. The Match column indicates this setting by displaying the “Do not match” icon. This setting does not mean the adaptive security appliance blocks traffic sent from the 192.168.10.0 network to TCP port 80 on the 192.168.20.0 network. Instead, this setting exempts the traffic from being matched by the service policy applied to the inside interface, which prevents the adaptive security appliance from sending the traffic to the CSC SSM.

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Licensing Requirements for the CSC SSM

The second class of the inside-policy, inside-class matches FTP, HTTP, and POP3 traffic between the inside network and any destination. HTTP connections to the DMZ network are exempted because of the inside-class1 setting. As previously mentioned, policies that apply CSC scanning to a specific interface affect both incoming and outgoing traffic, but by specifying 192.168.10.0 as the source network, inside-class1 matches only connections initiated by the hosts on the inside network.

In the outside-policy, outside-class matches SMTP traffic from any outside source to the DMZ network.

This setting protects the SMTP server and inside users who download e-mail from the SMTP server on the DMZ network, without having to scan connections from SMTP clients to the server.

If the web server on the DMZ network receives files uploaded by HTTP from external hosts, you can add a rule to the outside policy that matches HTTP traffic from any source to the DMZ network. Because the policy is applied to the outside interface, the rule would only match connections from HTTP clients outside the adaptive security appliance.



Model

ASA 5505

ASA 5510

ASA 5520

•


No support.






ASA 5540


For the ASA 5510, 5520, and 5540:

•

With a Base License, the features enabled by default are SMTP virus scanning, POP3 virus scanning and content filtering, webmail virus scanning, HTTP file blocking, FTP virus scanning and file blocking, logging, and automatic updates.

With a Security Plus License, the additional features enabled by default are SMTP anti-spam, SMTP content filtering,

POP3 anti-spam, URL blocking, and URL filtering

.

Prerequisites for the CSC SSM

The CSC SSM has the following prerequisites:

•

•

•

A CSC SSM card must be installed in the adaptive security appliance.

A Product Authorization Key (PAK) for use in registering the CSC SSM.

•

Activation keys that you receive by e-mail after you register the CSC SSM.

The management port of the CSC SSM must be connected to your network to allow management and automatic updates of the CSC SSM software.

•

•

The CSC SSM management port IP address must be accessible by the hosts used to run ASDM.

You must obtain the following information to use in configuring the CSC SSM:

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–

The CSC SSM management port IP address, netmask, and gateway IP address.

–

–

DNS server IP address.

HTTP proxy server IP address (needed only if your security policies require the use of a proxy server for HTTP access to the Internet).

–

–

Domain name and hostname for the CSC SSM.

An e-mail address and an SMTP server IP address and port number for e-mail notifications.

–

–

IP addresses of hosts or networks that are allowed to manage the CSC SSM. The IP addresses for the CSC SSM management port and the adaptive security appliance management interface can be in different subnets.

Password for the CSC SSM.






Supported in routed and transparent modes.


Does not support sessions in Stateful Failover. The CSC SSM does not maintain connection information, and therefore cannot provide the failover unit with the required information. The connections that a CSC

SSM is scanning are dropped when the adaptive security appliance in which the CSC SSM is installed fails. When the standby adaptive security appliance becomes active, it forwards the scanned traffic to the

CSC SSM and the connections are reset.

IPv6 Guidelines



Supported on the ASA 5510, ASA 5520, and ASA 5540 only.


Table 55-1 lists the default settings for the CSC SSM.

Table 55-1 Default CSC SSM Parameters

Parameter Default

FTP inspection on the adaptive security appliance Enabled

All features included in the license(s) that you have purchased

Enabled

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Configuring the CSC SSM


This section describes how to configure the CSC SSM and includes the following topics:

•

Before Configuring the CSC SSM, page 55-7

•

Connecting to the CSC SSM, page 55-8

Before Configuring the CSC SSM

Before configuring the adaptive security appliance and the CSC SSM, perform the following steps:

Step 1

Step 2

Step 3

Step 4

If the CSC SSM did not come preinstalled in a Cisco ASA 5500 series adaptive security appliance, install it and connect a network cable to the management port of the SSM. For assistance with installation and connecting the SSM, see the

Cisco ASA 5500 Series Adaptive Security Appliance Getting Started Guide

.

The management port of the CSC SSM must be connected to your network to allow management of and automatic updates to the CSC SSM software. Additionally, the CSC SSM uses the management port for e-mail notifications and syslog messages.

You should have received a Product Authorization Key (PAK) with the CSC SSM. Use the PAK to register the CSC SSM at the following URL.

http://www.cisco.com/go/license

After you register, you receive activation keys by e-mail. The activation keys are required before you can

complete Step 6

.

Obtain the following information for use in Step 6

:

•

Activation keys

•

•

•

CSC SSM management port IP address, netmask, and gateway IP address

DNS server IP address

•

•

•

HTTP proxy server IP address (needed only if your security policies require the use of a proxy server for HTTP access to the Internet)

Domain name and hostname for the CSC SSM

An e-mail address, and SMTP server IP address and port number for e-mail notifications

IP addresses of hosts or networks that are allowed to manage the CSC SSM

•

Password for the CSC SSM

In a web browser, access ASDM for the adaptive security appliance in which the CSC SSM is installed.

Note

If you are accessing ASDM for the first time, see the

“Additional References” section on page 55-14

.

Step 5

For more information about enabling ASDM access, see the

“Configuring Device Access for ASDM,

Telnet, or SSH” section on page 32-1

.

Verify time settings on the adaptive security appliance. Time setting accuracy is important for logging of security events and for automatic updates of CSC SSM software. Do one of the following:

•

If you manually control time settings, verify the clock settings, including time zone. Choose

Configuration > Properties > Device Administration > Clock

.

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55-7



Step 6

Step 7

Step 8

Step 9

•

If you are using NTP, verify the NTP configuration. Choose

Configuration > Properties > Device

Administration > NTP

.

Open ASDM.

Connect to and log in to the CSC SSM. For instructions, see the

“Connecting to the CSC SSM” section on page 55-8

.

Run the CSC Setup Wizard.

•

To access the CSC Setup Wizard, choose

Configuration > Trend Micro Content Security > CSC

Setup > Wizard Setup > Launch Setup Wizard

.

•

If you are rerunning the CSC Setup Wizard, perform the same steps listed in the previous bullet.

The CSC Setup Wizard appears.

Complete the CSC Setup Wizard, which includes configuration of service policies to divert traffic that you want scanned to the CSC SSM.

Note

If you create a global service policy to divert traffic for CSC scans, all traffic (inbound and outbound) for the supported protocols is scanned. To maximize performance of the adaptive security appliance and the CSC SSM, scan traffic only from untrusted sources.

Step 10

Step 11

To reduce the load on the CSC SSM, configure the service policy rules that send packets to the CSC SSM to support only HTTP, SMTP, POP3, or FTP traffic. For instructions, see the

“Determining Service

Policy Rule Actions for CSC Scanning” section on page 55-9

.

(Optional) Review the default content security policies in the CSC SSM GUI, which are suitable for most implementations. You review the content security policies by viewing the enabled features in the CSC

SSM GUI. For the availability of features, see the

“Licensing Requirements for the CSC SSM” section on page 55-5

. For the default settings, see the “Default Settings” section on page 55-6 .

What to Do Next

See the

“Connecting to the CSC SSM” section on page 55-8 .

Connecting to the CSC SSM

With each session you start in ASDM, the first time you access features related to the CSC SSM, you must specify the management IP address and provide the password for the CSC SSM. After you successfully connect to the CSC SSM, you are not prompted again for the management IP address and password. If you start a new ASDM session, the connection to the CSC SSM is reset and you must specify the IP address and the CSC SSM password again. The connection to the CSC SSM is also reset if you change the time zone on the adaptive security appliance.

Note

The CSC SSM has a password that is maintained separately from the ASDM password. You can configure the two passwords to be identical, but changing the CSC SSM password does not affect the

ASDM password.

55-8


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To connect to the CSC SSM, perform the following steps:

Step 1

Step 2

Step 3

Step 4

In the ASDM main application window, click the

Content Security

tab.

In the Connecting to CSC dialog box, click one of the following radio buttons:

•

To connect to the IP address of the management port on the SSM, click

Management IP Address

.

ASDM automatically detects the IP address for the SSM in the adaptive security appliance. If this detection fails, you can specify the management IP address manually.

•

To connect to an alternate IP address or hostname on the SSM, click

Other IP Address or

Hostname

.

Enter the port number in the Port field, and then click

Continue

.

In the CSC Password field, type your CSC password, and then click

OK

.

Step 5

Note

If you have not completed the CSC Setup Wizard (choose

Configuration > Trend Micro

Content Security > CSC Setup > Wizard Setup

), complete the configuration in the CSC

Setup Wizard, which includes changing the default password, “cisco.”

For ten minutes after you have entered the password, you do not need to reenter the CSC SSM password to access other parts of the CSC SSM GUI.

To access the CSC SSM GUI, choose

Configuration > Trend Micro Content Security

, and then click one of the following tabs:

Web

,

Mail

,

File Transfer

, or

Updates

.

What to Do Next

See the

“Determining Service Policy Rule Actions for CSC Scanning” section on page 55-9 .

Determining Service Policy Rule Actions for CSC Scanning

The CSC SSM scans only HTTP, SMTP, POP3, and FTP traffic. If your service policy includes traffic that supports other protocols in addition to these four, packets for other protocols are passed through the

CSC SSM without being scanned. You should configure the service policy rules that send packets to the

CSC SSM to support only HTTP, SMTP, POP3, or FTP traffic.

The CSC Scan tab in the Add Service Policy Rule Wizard lets you determine whether or not the CSC

SSM scans traffic identified by the current traffic class. This tab appears only if a CSC SSM is installed in the adaptive security appliance.

To configure service policy rules for CSC scanning, perform the following steps:

Step 1

Step 2

Step 3



.

On the toolbar, click

Add

.

The Add Service Policy Rule Wizard screen appears.

Click the


option, and then click

Next

.

The Traffic Classification Criteria screen appears.

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55-9


Monitoring the CSC SSM

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Click the


option, type a name for the traffic class in the adjacent field, check the

Any traffic

check box, and then click

Next

.

The Rule Actions screen appears.

Click the

CSC Scan

tab, and then check the

Enable CSC scan for this traffic flow

check box.

Choose whether the adaptive security appliance should permit or deny selected traffic to pass if the CSC

SSM is unavailable by making the applicable selection in the area labeled:

If CSC card fails, then

.

When this check box is checked, the other parameters on this tab become active.

In the If CSC card fails area, if the CSC SSM becomes inoperable, choose one of the following actions:

•

•

To allow traffic, check the

Permit traffic

check box.

To block traffic, check the

Close traffic

check box.

Click

Finish

.

The new service policy rule appears in the Service Policy Rules pane.

Click

Apply

.

The adaptive security appliance begins diverting traffic to the CSC SSM, which performs the content security scans that have been enabled according to the license that you purchased.

What to Do Next

See the

“Monitoring the CSC SSM” section on page 55-10

.


ASDM lets you monitor the CSC SSM statistics as well as CSC SSM-related features.

Note

If you have not completed the CSC Setup Wizard in Configuration > Trend Micro Content Security >

CSC Setup, you cannot access the panes under Monitoring > Trend Micro Content Security. Instead, a dialog box appears and lets you access the CSC Setup Wizard directly from Monitoring > Trend Micro

Content Security.

•

•

•


•

•

Threats, page 55-11

Live Security Events, page 55-11

Live Security Events Log, page 55-12

Software Updates, page 55-13

Resource Graphs, page 55-13

55-10


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Threats

To view information about various types of threats detected by the CSC SSM in a graph, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Choose

Monitoring > Trend Micro Content Security > Threats

.

The Available Graphs area lists the components whose statistics you can view in a graph. You can include a maximum of four graphs in one frame. The graphs display real-time data in 12-second intervals for the following:

•

•

•

•

•

•

Viruses detected

URLs filtered, URLs blocked

Spam detected

Files blocked

Spyware blocked

Damage Cleanup Services

The Graph Window Title lists the types of statistics available for monitoring. You can choose up to four types of statistics to show in one graph window. You can open multiple graph windows at the same time.

The statistics already included in the graph window appear in the Selected Graphs list.

To move the selected statistics type in the Available Graphs For list to the Selected Graphs list, click

Add

.

To remove the selected statistics type from the Selected Graphs list, click

Remove

. The button name changes to

Delete

if the item you are removing was added from another pane, and is not being returned to the Available Graphs pane.

To display a new window that shows a Graph tab and an updated graph with the selected statistics, click

Show Graphs

. Click the

Table

tab to display the same information in tabular form.

From the Graph or Table tab, click

Export

in the menu bar or choose

File > Export

to save the graph or tabular information as a file on your local PC.

From the Graph or Table tab, click

Print

in the menu bar or choose

File > Print

to print the information displayed in the window.

What to Do Next

See the

“Live Security Events” section on page 55-11

.

Live Security Events

To view live, real-time security events in a separate window, perform the following steps:

Step 1

Choose

Monitoring > Trend Micro Content Security > Live Security Events

.

The Buffer Limit field shows the maximum number of log messages that you may view. The default is

1000.

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Step 2

Click

View

to display the Live Security Events Log dialog box. You can pause incoming messages, clear the message window, and save event messages. You can also search messages for specific text.

What to Do Next

See the

“Live Security Events Log” section on page 55-12 .

Live Security Events Log

To view live security events messages that are received from the CSC SSM, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

To filter security event messages from the Filter By drop-down list, choose one of the following:

•

Filter by Text, type the text, then click

Filter

.

•

Show All, to display all messages or remove the filter.

To use the Latest CSC Security Events pane, in which all columns are

display-only

, choose one of the following options:

•

•

•

The time an event occurred.

The IP address or hostname from which the threat came.

•

The type of threat, or the security policy that determines event handling, or in the case of a URL filtering event, the filter that triggered the event.

The subject of e-mails that include a threat, or the names of FTP files that include a threat, or blocked or filtered URLs.

•

•

•

•

The recipient of e-mails that include a threat, or the IP address or hostname of a threatened node, or the IP address of a threatened client.

The type of event (such as Web, Mail, or FTP), or the name of a user or group for HTTP or FTP events, which include a threat.

The action taken upon the content of a message, such as cleaning attachments or deleting attachments.

The action taken on a message, such as delivering it unchanged, delivering it after deleting the attachments, or delivering it after cleaning the attachments.

To search security event messages based on the text that you enter, choose one of the following:

•

In the Text field, enter the text to search for in the security event messages log, then click

Find

Messages

.

•

To find the next entry that matches the text you typed in this field, click

Find

.

To pause scrolling of the Latest CSC Security Events pane, click

Pause

. To resume scrolling of the Latest

CSC Security Events pane, click

Resume

.

To save the log to a file on your PC, click

Save

.

To clear the list of messages shown, click

Clear Display

.

To close the pane and return to the previous one, click

Close

.

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What to Do Next

See the

“Software Updates” section on page 55-13 .


Software Updates

To view information about CSC SSM software updates, choose

Monitoring > Trend Micro Content

Security > Software Updates

.

The Software Updates pane displays the following information, which is refreshed automatically about every 12 seconds:

•

•

The names of parts of the CSC SSM software that can be updated.

The current version of the corresponding component.

•

•

The date and time that the corresponding component was last updated. If the component has not been updated since the CSC SSM software was installed, “None” appears in this column.

The date and time that ASDM last received information about CSC SSM software updates.

What to Do Next

See the

“CSC CPU” section on page 55-13

.

Resource Graphs

The adaptive security appliance lets you monitor CSC SSM status, including CPU resources and memory usage. This section includes the following topics:

•

•

CSC CPU, page 55-13

CSC Memory, page 55-14

CSC CPU

To view CPU usage by the CSC SSM in a graph, perform the following steps:

Step 1

Step 2

Choose

Monitoring > Trend Micro Content Security > Resource Graphs > CSC CPU

.

The CSC CPU pane displays the components whose statistics you can view in a graph, including statistics for CPU usage on the CSC SSM.

To continue, go to Step 2 of the

“Threats” section on page 55-11 .

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55-13



What to Do Next

See the

“CSC Memory” section on page 55-14

.

CSC Memory

To view information about memory usage on the CSC SSM in a graph, perform the following steps:

Step 1

Step 2

Choose

Monitoring > Trend Micro Content Security > Resource Graphs > CSC Memory

.

The Available Graphs area lists the components whose statistics you can view in a graph, including the following.

•

The amount of memory not in use.

•

The amount of memory in use.

To continue, go to Step 2 of the

“Threats” section on page 55-11

.


For instructions on how to use the CSC SSM GUI, see the

Cisco Content Security and Control (CSC)

SSM Administrator Guide.


For additional information related to implementing the CSC SSM, see the following documents:

Related Topic

Assistance with SSM hardware installation and connection to the adaptive security appliance.

Document Title

Cisco ASA 5500 Series Hardware Installation Guide

Accessing ASDM for the first time and assistance with the Startup Wizard.

Instructions on use of the CSC SSM GUI.

Additional licensing requirements of specific windows available in the CSC SSM GUI.

Reviewing the default content security policies in the CSC SSM GUI before modifying them or entering advanced configuration settings.

Technical Documentation, Marketing, and

Support-related information.



See the following URL: http://www.cisco.com/en/US/products/ps6823/index.html

.

55-14


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Feature History for the CSC SSM


Table 55-2


Table 55-2 Feature History for the CSC SSM

Feature Name

CSC SSM

CSC SSM

Platform Releases Feature Information

7.0(1) The CSC SSM runs Content Security and Control software, which provides protection against viruses, spyware, spam, and other unwanted traffic.

8.1(1) and 8.1(2)

CSC syslog format 8.3(1)

The CSC Setup Wizard enables you to configure the CSC SSM in ASDM. The following screen was introduced: Configuration > Trend Micro Content Security

> CSC Setup.

This feature is not supported on the ASA 5580.

Clearing CSC events

6.3(2)

CSC syslog format is consistent with the adaptive security appliance syslog format. Syslog message explanations have been added to the

Cisco Content

Security and Control (CSC) SSM Administrator Guide

. The source and destination

IP information has been added to the ASDM Log Viewer GUI. All syslog messages include predefined syslog priorities and cannot be configured through the CSC

SSM GUI.

Support for clearing CSC events in the Latest CSC Security Events pane has been added. The following screen was modified: Home > Content Security.

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55-16


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55-18


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C H A P T E R

56

Configuring Trend Micro Content Security

Note

The ASA 5580 does not support the CSC SSM feature.

This chapter describes how to configure the CSC SSM using the CSC Setup Wizard in ASDM and the

CSC SSM GUI, and includes the following sections:

•

•

•

•

•

•

•

•

•

•

Information About the CSC SSM, page 56-2

Licensing Requirements for the CSC SSM, page 56-2

Prerequisites for the CSC SSM, page 56-2



CSC SSM Setup, page 56-4

Using the CSC SSM GUI, page 56-13



Feature History for the CSC SSM, page 56-17

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56-1

Chapter 56 Configuring Trend Micro Content Security



The ASA 5500 series adaptive security appliance supports the CSC SSM, which runs Content Security and Control software. The CSC SSM provides protection against viruses, spyware, spam, and other unwanted traffic by scanning the FTP, HTTP, POP3, and SMTP packets that you configure the adaptive security appliance to send to it.



Model

ASA 5505

ASA 5510


No support.




ASA 5520

ASA 5540

•




For the ASA 5510, 5520, and 5540:

With a Base License, the features enabled by default are SMTP virus scanning, POP3 virus scanning and content filtering, webmail virus scanning, HTTP file blocking, FTP virus scanning and file blocking, logging, and automatic updates.

•

With a Security Plus License, the additional features enabled by default are SMTP anti-spam, SMTP content filtering,

POP3 anti-spam, URL blocking, and URL filtering

.

Prerequisites for the CSC SSM

The CSC SSM has the following prerequisites:

•

A CSC SSM card must be installed in the adaptive security appliance.

•

•

•

A Product Authorization Key (PAK) for use in registering the CSC SSM.

Activation keys that you receive by e-mail after you register the CSC SSM.

•

•

The management port of the CSC SSM must be connected to your network to allow management and automatic updates of the CSC SSM software.

The CSC SSM management port IP address must be accessible by the hosts used to run ASDM.

You must obtain the following information to use in configuring the CSC SSM:

–

The CSC SSM management port IP address, netmask, and gateway IP address.

–

–

DNS server IP address.

HTTP proxy server IP address (needed only if your security policies require the use of a proxy server for HTTP access to the Internet).

–

Domain name and hostname for the CSC SSM.

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–

–

–

An e-mail address and an SMTP server IP address and port number for e-mail notifications.

IP addresses of hosts or networks that are allowed to manage the CSC SSM. The IP addresses for the CSC SSM management port and the adaptive security appliance management interface can be in different subnets.

Password for the CSC SSM.




Supported in single and multiple context modes. In multiple-context mode, all panes under the CSC

Setup node are available

only

in the admin context. You can restore the default password only in multiple-context mode in the system context.




Does not support sessions in Stateful Failover. The CSC SSM does not maintain connection information, and therefore cannot provide the failover unit with the required information. The connections that a CSC

SSM is scanning are dropped when the adaptive security appliance in which the CSC SSM is installed fails. When the standby adaptive security appliance becomes active, it forwards the scanned traffic to the

CSC SSM and the connections are reset.

IPv6 Guidelines



Supported on the ASA 5510, ASA 5520, and ASA 5540 only.


Table 56-1

lists the default settings for the CSC SSM.

Table 56-1 Default CSC SSM Parameters

Parameter Default

FTP inspection on the adaptive security appliance Enabled

All features included in the license(s) that you have purchased

Enabled

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CSC SSM Setup

CSC SSM Setup

The CSC Setup Wizard lets you configure basic operational parameters for the CSC SSM. You must complete this wizard at least once before you can configure options in each screen separately. After you complete the CSC Setup Wizard, you can modify each screen individually without using this wizard again.

Additionally, you cannot access the panes under Configuration > Trend Micro Content Security > CSC

Setup or under Monitoring > Trend Micro Content Security > Content Security until you complete the

CSC Setup Wizard. If you try to access these panes before completing this wizard, a dialog box appears and lets you access the wizard directly to complete the configuration.


•

Activation/License, page 56-4

•

•

•

•

•

•

IP Configuration, page 56-5

Host/Notification Settings, page 56-5

Management Access Host/Networks, page 56-6

Password, page 56-7

Restoring the Default Password, page 56-8

Wizard Setup, page 56-8

Activation/License

The Activation/License pane lets you review or renew activation codes for the CSC SSM Base License and the Plus License.

You can use ASDM to configure CSC licenses only once each for the two licenses. Renewed license activation codes are downloaded automatically with scheduled software updates. Links to the licensing status pane and the CSC UI home pane appear at the bottom of this window. The serial number for the assigned license is filled in automatically.

To review license status or renew a license, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Choose

Configuration > Trend Micro Content Security > CSC Setup > Activation/License.

The Activation/License pane shows the following display-only information for the Base License and the

Plus License:

•

•

•

The name of the component.

The activation code for the corresponding Product field.

•

The status of the license. If the license is valid, the expiration date appears. If the expiration date has passed, this field indicates that the license has expired.

The maximum number of network devices that the Base License supports. The Plus License does not affect the number of network devices supported; therefore, the Nodes field does not appear in the Plus License area.

To review license status or renew your license, click the link provided.

To go to the CSC home pane in ASDM, click the link provided.

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CSC SSM Setup

What to Do Next

See the

“IP Configuration” section on page 56-5

.

IP Configuration

The IP Configuration pane lets you configure management access for the CSC SSM, the DNS servers it should use, and a proxy server for retrieving CSC SSM software updates.

To configure management access and other related details for the CSC SSM, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Choose

Configuration > Trend Micro Content Security > CSC Setup > IP Configuration

.

Set the following parameters for management access to the CSC SSM:

•

Enter the IP address for management access to the CSC SSM.

•

•

Enters the netmask for the network containing the management IP address of the CSC SSM.

Enter the IP address of the gateway device for the network that includes the management IP address of the CSC SSM.

Set parameters of the DNS servers for the network that includes the management IP address of the CSC

SSM.

•

Enter the IP address of the primary DNS server.

•

(Optional) Enter the IP address of the secondary DNS server.

(Optional) Enter parameters for an HTTP proxy server, used by the CSC SSM to contact a CSC SSM software update server. If your network configuration does not require the CSC SSM to use a proxy server, leave the fields in this group blank.

•

•

Enter the IP address of the proxy server.

Enter the listening port of the proxy server.

What to Do Next

See the

“Host/Notification Settings” section on page 56-5 .

Host/Notification Settings

The Host/Notification Settings pane lets you configure details about hostname, domain name, e-mail notifications, and a domain name for e-mail to be excluded from detailed scanning.

To configure host and notification settings, perform the following steps:

Step 1

Step 2

Choose Configuration > Trend Micro Content Security > CSC Setup > Host/Notification Settings.

In the Host and Domain Names area, set the hostname and domain name of the CSC SSM.

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CSC SSM Setup

Step 3

In the Incoming E-mail Domain Name area, set the trusted incoming e-mail domain name for

SMTP-based e-mail. The CSC SSM scans SMTP e-mail sent to this domain. The types of threats that the CSC SSM scans for depend on the license that you purchased for the CSC SSM and the configuration of the CSC SSM software.

Note

CSC SSM lets you configure a list of many incoming e-mail domains. ASDM displays only the first domain in the list. To configure additional incoming e-mail domains, access the CSC SSM interface. To do so, choose

Configuration > Trend Micro Content Security > CSC Setup >

Mail,

and then click one of the links. After logging in to the CSC SSM, choose

Mail (SMTP) >

Configuration

, and then click the

Incoming Mail

tab.

Step 4

Configure the following settings for e-mail notification of events:

•

•

•

The administrator e-mail address for the account to which notification e-mails should be sent.

The IP address of the SMTP server.

The port to which the SMTP server listens.

What to Do Next

See the

“Management Access Host/Networks” section on page 56-6 .

Management Access Host/Networks

The Management Access Host/Networks pane lets you specify the hosts and networks for which management access to the CSC SSM is permitted. You must specify at least one permitted host or network, up to a maximum of eight permitted hosts or networks.

To specify hosts and networks for which management access to the CSC SSM is allowed, perform the following steps:

Step 1

Step 2

Step 3

Choose

Configuration > Trend Micro Content Security > CSC Setup > Management Access

Host/Networks

.

Enter the IP address of a host or network that you want to add to the Selected Hosts/Network list.

Enter the netmask for the host or network that you specified in the IP Address field.

Note

To allow all hosts and networks, enter

0.0.0.0

in the IP Address field, and choose 0.0.0.0 from the Mask list.

Step 4

Step 5

The Selected Hosts/Networks list displays the hosts or networks trusted for management access to the

CSC SSM.

To add the host or network that you specified in the IP Address field in the Selected Hosts/Networks list, click

Add

.

To remove a host or network from the Selected Hosts/Networks list, choose an entry from the list and click

Delete

.

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CSC SSM Setup

What to Do Next

See the

“Password” section on page 56-7 .

Password

The Password pane lets you change the password required for management access to the CSC SSM. The

CSC SSM has a password that is maintained separately from the ASDM password. You can configure them to be identical; however, changing the CSC SSM password does not affect the ASDM password.

If ASDM is connected to the CSC SSM and you change the CSC SSM password, the connection to the

CSC SSM is dropped. As a result, ASDM displays a confirmation dialog box that you must respond to before the password is changed.

Tip

Whenever the connection to the CSC SSM is dropped, you can reestablish it. To do so, click the

Connection to Device

icon on the status bar to display the Connection to Device dialog box, and then click

Reconnect

. ASDM prompts you for the CSC SSM password, which is the new password that you have defined.

Passwords must be 5 - 32 characters long.

Passwords appears as asterisks when you type them.

Note

The default password is “cisco.”

To change the password required for management access to the CSC SSM, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Choose

Configuration > Trend Micro Content Security > CSC Setup > Password

.

In the Old Password field, enter the current password for management access to the CSC SSM.

In the New Password field, enter the new password for management access to the CSC SSM.

In the Confirm New Password field, reenter the new password for management access to the CSC SSM.

What to Do Next

If required, see the “Restoring the Default Password” section on page 56-8 .

See the

“Wizard Setup” section on page 56-8

.

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56-7


CSC SSM Setup

Restoring the Default Password

You can use ASDM to reset the CSC SSM password. You can reset this password to the default value, which is “cisco” (excluding quotation marks). If the CSC password-reset policy has been set to

“Denied,” then you cannot reset the password through the ASDM CLI. To change this policy, you must access the CSC SSM through the adaptive security appliance CLI by entering the

session

command. For more information, see the Cisco Content Security and Control (CSC) SSM Administrator Guide.

Note

This option does not appear in the menu if an SSM is not installed.

To reset the CSC SSM password to the default value, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Choose

Tools > CSC Password Reset

.

The CSC Password Reset confirmation dialog box appears.

Click

OK

to reset the CSC SSM password to the default value.

A dialog box appears, indicating the success or failure of the password reset. If the password was not reset, make sure you are using Version 8.0(2) software on the adaptive security appliance and the most recent Version 6.1.x software on the CSC SSM.

Click

Close

to close the dialog box.

After you have reset the password, you should change it to a unique value.

What to Do Next

See the

“Password” section on page 56-7

.

Wizard Setup

The Wizard Setup screen lets you start the CSC Setup Wizard. To start the CSC Setup Wizard, click

Launch Setup Wizard

. To access the Wizard Setup screen, choose

Configuration > Trend Micro

Content Security > CSC Setup > Wizard Setup

.

Before you can directly access any of the other screens under CSC Setup, you must complete the CSC

Setup Wizard. This wizard includes the following screens:

•

•

•

CSC Setup Wizard Activation Codes Configuration, page 56-9

CSC Setup Wizard IP Configuration, page 56-9

CSC Setup Wizard Host Configuration, page 56-9

CSC Setup Wizard Management Access Configuration, page 56-10

•

•

•

CSC Setup Wizard Password Configuration, page 56-10

CSC Setup Wizard Traffic Selection for CSC Scan, page 56-11

•

CSC Setup Wizard Summary, page 56-12

After you complete the CSC Setup Wizard once, you can change any settings in screens related to the

CSC SSM without using the CSC Setup Wizard again.

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CSC SSM Setup

CSC Setup Wizard Activation Codes Configuration

To display the activation codes that you have entered to enable features on the CSC SSM, perform the following steps:

Choose

Configuration > Trend Micro Content Security > CSC Setup > Activation/License

.

The activation code settings that you have made appear on this screen, according to the type of license you have, as follows:

•

The activation code for the Base License appears. The Base License includes anti-virus, anti-spyware, and file blocking.

•

The activation code for the Plus License appears, if you have entered one. If not, this field is blank.

The Plus License includes anti-spam, anti-phishing, content filtering, URL blocking and filtering, and web reputation.

What to Do Next

See the

“CSC Setup Wizard IP Configuration” section on page 56-9

.

CSC Setup Wizard IP Configuration

To display the IP configuration settings that you have entered for the CSC SSM, perform the following steps:

Choose

Configuration > Trend Micro Content Security > CSC Setup > IP Configuration

.

The IP configuration settings that you have entered for the CSC SSM appear, including the following:

•

The IP address for the management interface of the CSC SSM.

•

•

The network mask for the management interface of the CSC SSM that you have selected from the drop-down list.

The IP address of the gateway device for the network that contains the CSC SSM management interface.

•

•

•

•

The primary DNS server IP address.

The secondary DNS server IP address (if configured).

The proxy server (if configured).

The proxy port (if configured).

What to Do Next

See the

“CSC Setup Wizard IP Configuration” section on page 56-9

.

CSC Setup Wizard Host Configuration

To display the host configuration settings that you have entered for the CSC SSM, perform the following steps:

Choose

Configuration > Trend Micro Content Security > CSC Setup > Host Configuration

.

The host configuration settings that you have entered for the CSC SSM appear, including the following:

•

•

The hostname of the CSC SSM.

The name of the domain in which the CSC SSM resides.


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CSC SSM Setup

•

•

•

•

The domain name for incoming e-mail.

The e-mail address of the domain administrator.

The IP address of the e-mail server.

The port number through which you connect to the CSC SSM.

What to Do Next

See the

“CSC Setup Wizard Management Access Configuration” section on page 56-10

.

CSC Setup Wizard Management Access Configuration

To display the subnet and host settings that you have entered to grant access to the CSC SSM, perform the following steps:

Step 1

Step 2

Step 3

Choose

Configuration > Trend Micro Content Security > CSC Setup > Management Access

Configuration

.

The management access configuration settings that you have entered for the CSC SSM appear, including the following:

•

•

The IP address for networks and hosts that are allowed to connect to the CSC SSM.

The network mask for networks and hosts that are allowed to connect to the CSC SSM that you have selected from the drop-down list.

To add the IP address of the networks and hosts that you want to allow to connect to the CSC SSM, click

Add

.

To remove the IP address of a network or host whose ability to connect to the CSC SSM you no longer want, click

Delete

.

The Selected Hosts/Networks table lists the IP addresses of networks and hosts whose connection to the

CSC SSM you have added.

What to Do Next

See the

“CSC Setup Wizard Password Configuration” section on page 56-10

.

CSC Setup Wizard Password Configuration

To change the password required for management access to the CSC SSM, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Choose

Configuration > Trend Micro Content Security > CSC Setup > Password

.

In the Old Password field, enter the current password for management access to the CSC SSM.

In the New Password field, enter the new password for management access to the CSC SSM.

In the Confirm New Password field, reenter the new password for management access to the CSC SSM.

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CSC SSM Setup

What to Do Next

See the

“CSC Setup Wizard Traffic Selection for CSC Scan” section on page 56-11 .

CSC Setup Wizard Traffic Selection for CSC Scan

To display the settings that you have made to select traffic for CSC scanning, perform the following steps:

Step 1

Step 2

Choose

Configuration > Trend Micro Content Security > CSC Setup > Traffic Selection for CSC

Scan

.

The traffic selection for CSC scanning configuration settings that you have entered for the CSC SSM appear, including the following:

•

The interface to the CSC SSM that you have chosen from the drop-down list.

•

•

•

The source or destination service for the CSC SSM to scan.


•

The source of network traffic for the CSC SSM to scan.

The destination of network traffic for the CSC SSM to scan.

•

To specify additional traffic details for CSC scanning, click

Add

. For more information, see

“Specifying Traffic for CSC Scanning” section on page 56-11 .

To modify additional traffic details for CSC scanning, click

Edit

. For more information, see

“Specifying Traffic for CSC Scanning” section on page 56-11 .

•

To remove additional traffic details for CSC scanning, click

Delete

.

Specifying Traffic for CSC Scanning

To define, modify, or remove additional settings for selecting traffic for CSC scanning, perform the following steps:

Step 3

Step 4

Step 5

Step 6

Step 7

Step 1

Step 2

Step 8

In the Traffic Selection for CSC Scan screen, click

Specify traffic for CSC Scan

.

The Specify traffic for CSC Scan dialog box appears.

Choose the type of interface to the CSC SSM from the drop-down list. Available settings are global (all interfaces), inside, management, and outside.

Choose the source of network traffic for the CSC SSM to scan from the drop-down list.

Choose the destination of network traffic for the CSC SSM to scan from the drop-down list.

Choose the type of service for the CSC SSM to scan from the drop-down list.

Enter a description for the network traffic that you define for the CSC SSM to scan.

Specify whether or not to allow the CSC SSM to scan network traffic if the CSC card fails. Choose one of the following options:

•

•

To allow traffic through without being scanned, click

Permit

.

To prevent traffic from going through without being scanned, click

Close

.

Click

OK


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CSC SSM Setup

Step 9

The added traffic details appear on the CSC Setup Wizard Traffic selection for CSC Scan screen.

Click

Cancel

to discard these settings and return to the CSC Setup Wizard Traffic selection for CSC

Scan screen. If you click

Cancel

, ASDM displays a dialog box to confirm your decision.

What to Do Next

See the

“CSC Setup Wizard Summary” section on page 56-12

.

CSC Setup Wizard Summary

To review the settings that you have made with the CSC Setup Wizard, perform the following steps:

Step 1

Step 2

Choose

Configuration > Trend Micro Content Security > CSC Setup > Summary

.

The CSC Setup Wizard Summary screen shows the following display-only settings:

•

•

The settings that you made in the Activation Codes Configuration screen, including the Base

License activation code and the Plus License activation code, if you entered one. If not, this field is blank.

The settings that you made in the IP Configuration screen, including the following information:

–

–

IP address and netmask for the management interface of the CSC SSM.

IP address of the gateway device for the network that includes the CSC SSM management interface.

•

–

–

Primary DNS server IP address.

Secondary DNS server IP address (if configured).

–

Proxy server and port (if configured).

The settings that you made in the Host Configuration screen, including the following information:

–

–

Hostname of the CSC SSM.

Domain name for the domain that includes the CSC SSM.

–

–

Domain name for incoming e-mail.

Administrator e-mail address.

•

–

E-mail server IP address and port number.

The settings that you made on the Management Access Configuration screen. The drop-down list includes the hosts and networks from which the CSC SSM allows management connections.

•

Indicates whether or not you have changed the password in the Password Configuration screen.

(Optional) Click

Back

to return to the previous screens of the CSC Setup Wizard to change any settings.

Note

The Next button is dimmed; however, if you click

Back

to access any of the preceding screens in this wizard, click

Next

to return to the Summary screen.

Step 3

Click

Finish

to complete the CSC Setup Wizard and save all settings that you have specified. After you click

Finish

, you can change any settings related to the CSC SSM without using the CSC Setup Wizard again.

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Using the CSC SSM GUI

Step 4

Step 5

A summary of the status of commands that were sent to the device appears.

Click

Close

to close this screen, and then click

Next

.

A message appears indicating that the CSC SSM has been activated and is ready for use.

(Optional) Click

Cancel

to exit the CSC Setup Wizard without saving any of the selected settings. If you click

Cancel

, a dialog box appears to confirm your decision.

What to Do Next

See the

“Using the CSC SSM GUI” section on page 56-13

.

Using the CSC SSM GUI

This section describes how to configure features using the CSC SSM GUI, and includes the following topics:

•

Web, page 56-13

•

•

•

Mail, page 56-14

File Transfer, page 56-15

Updates, page 56-16

Web

Note

To access the CSC SSM, you must reenter the CSC SSM password. Sessions in the CSC SSM browser time out after ten minutes of inactivity. If you close the CSC SSM browser and click another link in

ASDM, you are not prompted for the CSC SSM password again, because one session is already open.

To view whether or not web-related features are enabled and access the CSC SSM GUI for configuring these features, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Choose

Configuration > Trend Micro Content Security > Web

.

The URL Blocking and Filtering area is display-only and shows whether or not URL blocking is enabled on the CSC SSM.

Click

Configure URL Blocking

to open a screen for configuring URL blocking on the CSC SSM.

The URL Filtering area is display-only and shows whether or not URL filtering is enabled on the CSC

SSM.

Click

Configure URL Filtering

to open a screen for configuring URL filtering rules on the CSC SSM.

The File Blocking area is display-only and shows whether or not URL file blocking is enabled on the

CSC SSM.

Click

Configure File Blocking

to open a screen for configuring file blocking settings on the CSC SSM.

The HTTP Scanning area is display-only and shows whether or not HTTP scanning is enabled on the

CSC SSM.

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56-13

Mail


Step 5

Step 6

Click

Configure Web Scanning

to open a screen for configuring HTTP scanning settings on the CSC

SSM.

The Web Reputation area is display-only and shows whether or not the Web Reputation service is enabled on the CSC SSM.

Click

Configure Web Reputation

to open a screen for configuring the Web Reputation service on the

CSC SSM.

What to Do Next

See the

“Mail” section on page 56-14

.

Mail

The Mail pane lets you see whether or not e-mail-related features are enabled and lets you access the

CSC SSM GUI to configure these features. To configure e-mail related features, choose

Configuration

> Trend Micro Content Security > Mail

.


•

SMTP Tab, page 56-14

•

POP3 Tab, page 56-15

SMTP Tab

Note



To configure SMTP scanning, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Click the

SMTP

Tab.

The Incoming Scan area is display-only and shows whether or not the incoming SMTP scanning feature is enabled on the CSC SSM. Click

Configure Incoming Scan

to open a screen for configuring incoming

SMTP scan settings on the CSC SSM.

The Outgoing Scan area is display-only and shows whether or not the outgoing SMTP scanning feature is enabled on the CSC SSM. Click

Configure Outgoing Scan

to open a screen for configuring outgoing

SMTP scan settings on the CSC SSM.

The Incoming Filtering area is display-only and shows whether or not content filtering for incoming

SMTP e-mail is enabled on the CSC SSM. Click

Configure Incoming Filtering

to open a screen for configuring incoming SMTP e-mail content filtering settings on the CSC SSM.

The Outgoing Filtering area is display-only and shows whether or not content filtering for outgoing

SMTP e-mail is enabled on the CSC SSM. Click

Configure Outgoing Filtering

to open a screen for configuring outgoing SMTP e-mail content filtering settings on the CSC SSM.

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File Transfer

Step 6

The Anti-spam area is display-only and shows whether or not the SMTP anti-spam feature is enabled on the CSC SSM. Click

Configure Anti-spam

to open a screen for configuring SMTP anti-spam settings, including E-mail Reputation, on the CSC SSM.

POP3 Tab

Note



To configure POP3 scanning, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Click the

POP3

Tab.

The Scanning area is display-only and shows whether or not POP3 e-mail scanning is enabled on the

CSC SSM. Click

Configure Scanning

to open a window for configuring POP3 e-mail scanning on the

CSC SSM.

The Anti-spam area is display-only and shows whether or not the POP3 anti-spam feature is enabled on the CSC SSM. Click

Configure Anti-spam

to open a window for configuring the POP3 anti-spam feature on the CSC SSM.

The Content Filtering area is display-only and shows whether or not POP3 e-mail content filtering is enabled on the CSC SSM. Click

Configure Content Filtering

to open a window for configuring POP3 e-mail content filtering on the CSC SSM.

What to Do Next

See the

“File Transfer” section on page 56-15

.

File Transfer

The File Transfer pane lets you view whether or not FTP-related features are enabled and lets you access the CSC SSM for configuring FTP-related features.

Note



To view the status or configure FTP-related features, perform the following steps:

Step 1

Click the

File Transfer

tab.

The File Scanning area is display-only and shows whether or not FTP file scanning is enabled on the

CSC SSM.

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56-15


Updates

Step 2

Step 3

Click

Configure File Scanning

to open a window for configuring FTP file scanning settings on the CSC

SSM.

The File Blocking area is display-only and shows whether or not FTP blocking is enabled on the CSC

SSM.

Click

Configure File Blocking

to open a window for configuring FTP file blocking settings on the CSC

SSM.

What to Do Next

See the

“Updates” section on page 56-16 .

Updates

The Updates pane lets you view whether or not scheduled updates are enabled and lets you access the

CSC SSM for configuring scheduled updates.

Note



To view the status or configure scheduled update settings, perform the following steps:

Step 1

Step 2

Click the

Updates

tab.

The Scheduled Updates area is display-only and shows whether or not scheduled updates are enabled on the CSC SSM.

The Scheduled Update Frequency area displays information about when updates are scheduled to occur, such as “Hourly at 10 minutes past the hour.”

The Component area displays names of parts of the CSC SSM software that can be updated.

In the Components area, the Scheduled Updates area is display-only and shows whether or not scheduled updates are enabled for the corresponding components.

Click

Configure Updates

to open a window for configuring scheduled update settings on the CSC SSM.

Note

If you restart the adaptive security appliance, the SSM is not automatically restarted. For more information, see the “Managing SSMs and SSCs” section in the

Cisco ASA 5500 Series Configuration

Guide using the CLI

.


See the

“Monitoring the CSC SSM” section on page 55-10

.

56-16


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For additional information related to implementing the CSC SSM, see the following documents:

Related Topic Document Title

Instructions on use of the CSC SSM GUI.

Additional licensing requirements of specific windows available in the CSC SSM GUI.

Reviewing the default content security policies in the CSC SSM GUI before modifying them or entering advanced configuration settings.


Accessing ASDM for the first time and assistance with the Startup Wizard.

Assistance with SSM hardware installation and connection to the adaptive security appliance.


Cisco ASA 5500 Series Hardware Installation Guide

Technical Documentation, Marketing, and

Support-related information

See the following URL: http://www.cisco.com/en/US/products/ps6823/index.html

.


Table 56-2

lists the release history for this feature. ASDM is backwards-compatible with multiple platform releases, so the specific ASDM release in which support was added is not listed.

Table 56-2 Feature History for the CSC SSM

Feature Name

CSC SSM

CSC SSM

Syslog format

Releases Feature Information

ASA 7.0(1) The CSC SSM runs Content Security and Control software, which provides protection against viruses, spyware, spam, and other unwanted traffic.

The CSC Setup Wizard enables you to configure the CSC SSM in ASDM. The following screen was introduced:

Configuration > Trend Micro Content Security > CSC Setup

.

This feature is not supported.

ASA 8.1(1),

ASA 8.1(2)

ASA 8.3(1) CSC syslog format is consistent with the adaptive security appliance syslog format.

Syslog message explanations have been added to the

Cisco Content Security and Control

(CSC) SSM Administrator Guide

. The source and destination IP information has been added to the ASDM Log Viewer GUI. All syslog messages include predefined syslog priorities and cannot be configured through the CSC SSM GUI.

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P

A R T

1 3

Configuring High Availability

C H A P T E R

57

Information About High Availability

This chapter provides an overview of the failover features that enable you to achieve high availability on the Cisco 5500 series adaptive security appliances. For information about configuring high availability, see

Chapter 60, “Configuring Active/Active Failover”

or Chapter 59, “Configuring Active/Standby

Failover.”


•

•

•

•

•

Information About Failover and High Availability, page 57-1

Failover System Requirements, page 57-2

Failover and Stateful Failover Links, page 57-2

Active/Active and Active/Standby Failover, page 57-5

•

•

•

•

•

Stateless (Regular) and Stateful Failover, page 57-6

Auto Update Server Support in Failover Configurations, page 57-8

Failover Health Monitoring, page 57-10

Failover Feature/Platform Matrix, page 57-12

Failover Times by Platform, page 57-12

Failover Messages, page 57-13

Information About Failover and High Availability

Configuring high availability requires two identical adaptive security appliances connected to each other through a dedicated failover link and, optionally, a Stateful Failover link. The health of the active interfaces and units is monitored to determine if specific failover conditions are met. If those conditions are met, failover occurs.

The adaptive security appliance supports two failover configurations, Active/Active failover and

Active/Standby failover. Each failover configuration has its own method for determining and performing failover.

With Active/Active failover, both units can pass network traffic. This also lets you configure traffic sharing on your network. Active/Active failover is available only on units running in multiple context mode.

With Active/Standby failover, only one unit passes traffic while the other unit waits in a standby state.

Active/Standby failover is available on units running in either single or multiple context mode.

Both failover configurations support stateful or stateless (regular) failover.

OL-20339-01


57-1

Chapter 57 Information About High Availability

Failover System Requirements

Note

When the security appliance is configured for Active/Active Stateful Failover, you cannot enable IPsec or SSL VPN. Therefore, these features are unavailable. VPN failover is available for Active/Standby failover configurations only.

Failover System Requirements

This section describes the hardware, software, and license requirements for adaptive security appliances in a failover configuration.


•

•

•

Hardware Requirements, page 57-2

Software Requirements, page 57-2

License Requirements, page 57-2

Hardware Requirements

The two units in a failover configuration must be the same model, have the same number and types of interfaces, the same SSMs installed (if any), and the same RAM installed.

If you are using units with different flash memory sizes in your failover configuration, make sure the unit with the smaller flash memory has enough space to accommodate the software image files and the configuration files. If it does not, configuration synchronization from the unit with the larger flash memory to the unit with the smaller flash memory will fail.

Software Requirements

The two units in a failover configuration must be in the same operating modes (routed or transparent, single or multiple context). They must have the same major (first number) and minor (second number) software version. However, you can use different versions of the software during an upgrade process; for example, you can upgrade one unit from Version 7.0(1) to Version 7.0(2) and have failover remain active.

We recommend upgrading both units to the same version to ensure long-term compatibility.

License Requirements

The two units in a failover configuration do not need to have identical licenses; the licenses combine to make a failover cluster license. See the

“Failover Licenses” section on page 4-19 for more information.

Failover and Stateful Failover Links

This section describes the failover and the Stateful Failover links, which are dedicated connections between the two units in a failover configuration. This section includes the following topics:

•

Failover Link, page 57-3

•

Stateful Failover Link, page 57-3

57-2


OL-20339-01



Failover Link

The two units in a failover pair constantly communicate over a failover link to determine the operating status of each unit. The following information is communicated over the failover link:

•

The unit state (active or standby)

•

•

•

•

Hello messages (keep-alives)

Network link status

MAC address exchange

Configuration replication and synchronization

Caution

All information sent over the failover and Stateful Failover links is sent in clear text unless you secure the communication with a failover key. If the adaptive security appliance is used to terminate VPN tunnels, this information includes any usernames, passwords and preshared keys used for establishing the tunnels. Transmitting this sensitive data in clear text could pose a significant security risk. We recommend securing the failover communication with a failover key if you are using the adaptive security appliance to terminate VPN tunnels.

You can use any unused Ethernet interface on the device as the failover link; however, you cannot specify an interface that is currently configured with a name. The LAN failover link interface is not configured as a normal networking interface; it exists for failover communication only. This interface should only be used for the LAN failover link (and optionally for the Stateful Failover link).

Connect the LAN failover link in one of the following two ways:

•

•

Using a switch, with no other device on the same network segment (broadcast domain or VLAN) as the LAN failover interfaces of the adaptive security appliance.

Using a crossover Ethernet cable to connect the appliances directly, without the need for an external switch.

Note

When you use a crossover cable for the LAN failover link, if the LAN interface fails, the link is brought down on both peers. This condition may hamper troubleshooting efforts because you cannot easily determine which interface failed and caused the link to come down.

Note

The adaptive security appliance supports Auto-MDI/MDIX on its copper Ethernet ports, so you can either use a crossover cable or a straight-through cable. If you use a straight-through cable, the interface automatically detects the cable and swaps one of the transmit/receive pairs to MDIX.

Stateful Failover Link

To use Stateful Failover, you must configure a Stateful Failover link to pass all state information. You have three options for configuring a Stateful Failover link:

•

•

•

You can use a dedicated Ethernet interface for the Stateful Failover link.

If you are using LAN-based failover, you can share the failover link.

You can share a regular data interface, such as the inside interface. However, this option is not recommended.


OL-20339-01 57-3



If you are using a dedicated Ethernet interface for the Stateful Failover link, you can use either a switch or a crossover cable to directly connect the units. If you use a switch, no other hosts or routers should be on this link.

Note

Enable the PortFast option on Cisco switch ports that connect directly to the adaptive security appliance.

If you use a data interface as the Stateful Failover link, you receive the following warning when you specify that interface as the Stateful Failover link:

******* WARNING ***** WARNING ******* WARNING ****** WARNING *********

Sharing Stateful failover interface with regular data interface is not

a recommended configuration due to performance and security concerns.

******* WARNING ***** WARNING ******* WARNING ****** WARNING *********

Sharing a data interface with the Stateful Failover interface can leave you vulnerable to replay attacks.

Additionally, large amounts of Stateful Failover traffic may be sent on the interface, causing performance problems on that network segment.

Note

Using a data interface as the Stateful Failover interface is supported in single context, routed mode only.

In multiple context mode, the Stateful Failover link resides in the system context. This interface and the failover interface are the only interfaces in the system context. All other interfaces are allocated to and configured from within security contexts.

Note

The IP address and MAC address for the Stateful Failover link does not change at failover unless the

Stateful Failover link is configured on a regular data interface.

Caution

All information sent over the failover and Stateful Failover links is sent in clear text unless you secure the communication with a failover key. If the adaptive security appliance is used to terminate VPN tunnels, this information includes any usernames, passwords, and preshared keys used for establishing the tunnels. Transmitting this sensitive data in clear text could pose a significant security risk. We recommend securing the failover communication with a failover key if you are using the adaptive security appliance to terminate VPN tunnels.

Failover Interface Speed for Stateful Links

If you use the failover link as the Stateful Failover link, you should use the fastest Ethernet interface available. If you experience performance problems on that interface, consider dedicating a separate interface for the Stateful Failover interface.

Use the following failover interface speed guidelines for the adaptive security appliances:

•

Cisco ASA 5510

•

–

Stateful link speed can be 100 Mbps, even though the data interface can operate at 1 Gigabit due to the CPU speed limitation.

Cisco ASA 5520/5540/5550

–

Stateful link speed should match the fastest data link.

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Active/Active and Active/Standby Failover

•

Cisco ASA 5580

–

Use only non-management 1 Gigabit ports for the stateful link because management ports have lower performance and cannot meet the performance requirement for Stateful Failover.

For optimum performance when using long distance LAN failover, the latency for the failover link should be less than 10 milliseconds and no more than 250 milliseconds. If latency is more than10 milliseconds, some performance degradation occurs due to retransmission of failover messages.

All platforms support sharing of failover heartbeat and stateful link, but we recommend using a separate heartbeat link on systems with high Stateful Failover traffic.

Active/Active and Active/Standby Failover

Two types of failover configurations are supported by the adaptive security appliance: Active/Standby and Active/Active.

In Active/Standby failover, one unit is the active unit. It passes traffic. The standby unit does not actively pass traffic. When a failover occurs, the active unit fails over to the standby unit, which then becomes active. You can use Active/Standby failover for adaptive security appliances in single or multiple context mode, although it is most commonly used for adaptive security appliances in single context mode.

Active/Active failover is only available to adaptive security appliances in multiple context mode. In an

Active/Active failover configuration, both adaptive security appliances can pass network traffic. In

Active/Active failover, you divide the security contexts on the adaptive security appliance into

failover groups

. A failover group is simply a logical group of one or more security contexts. Each group is assigned to be active on a specific adaptive security appliance in the failover pair. When a failover occurs, it occurs at the failover group level.

For more detailed information about each type of failover, refer the following information:

•

•

Chapter 59, “Configuring Active/Standby Failover”

Chapter 60, “Configuring Active/Active Failover”

Determining Which Type of Failover to Use

The type of failover you choose depends upon your adaptive security appliance configuration and how you plan to use the adaptive security appliances.

If you are running the adaptive security appliance in single mode, then you can use only Active/Standby failover. Active/Active failover is only available to adaptive security appliances running in multiple context mode.

If you are running the adaptive security appliance in multiple context mode, then you can configure either Active/Active failover or Active/Standby failover.

•

To allow both members of the failover pair to share the traffic, use Active/Active failover. Do not exceed 50% load on each device.

•

If you do not want to share the traffic in this way, use Active/Standby or Active/Active failover.

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57-5


Stateless (Regular) and Stateful Failover

Table 57-1 provides a comparison of some of the features supported by each type of failover

configuration:

Table 57-1 Failover Configuration Feature Support

Feature

Single Context Mode

Multiple Context Mode

Traffic Sharing Network Configurations

Unit Failover

Failover of Groups of Contexts

Failover of Individual Contexts

Active/Active

No

Yes

Yes

Yes

Yes

No

Active/Standby

Yes

Yes

No

Yes

No

No


The adaptive security appliance supports two types of failover, regular and stateful. This section includes the following topics:

•

Stateless (Regular) Failover, page 57-6

•

Stateful Failover, page 57-6

Stateless (Regular) Failover

When a failover occurs, all active connections are dropped. Clients need to reestablish connections when the new active unit takes over.

Note

In Version 8.0 and later, some configuration elements for WebVPN (such as bookmarks and customization) use the VPN failover subsystem, which is part of Stateful Failover. You must use Stateful

Failover to synchronize these elements between the members of the failover pair. Stateless (regular) failover is not recommended for WebVPN.

Stateful Failover

When Stateful Failover is enabled, the active unit continually passes per-connection state information to the standby unit. After a failover occurs, the same connection information is available at the new active unit. Supported end-user applications are not required to reconnect to keep the same communication session.

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Table 57-2

list the state information that is and is not passed to the standby unit when Stateful Failover is enabled.

Table 57-2 State Information

State Information Passed to Standby Unit

NAT translation table

State Information Not Passed to Standby Unit

The HTTP connection table (unless HTTP replication is enabled).

The user authentication (uauth) table.

TCP connection states

UDP connection states

The ARP table

The Layer 2 bridge table (when running in transparent firewall mode)

The routing tables. After a failover occurs, some packets may be lost or routed out of the wrong interface (the default route) while the dynamic routing protocols rediscover routes.

State information for Security Service Modules.

DHCP server address leases.

The HTTP connection states (if HTTP replication is enabled)

The ISAKMP and IPSec SA table

Stateful Failover for phone proxy. When the active unit goes down, the call fails, media stops flowing, and the phone should unregister from the failed unit and reregister with the active unit. The call must be re-established.

—

GTP PDP connection database

SIP signalling sessions

—

—

The following WebVPN features are not supported with Stateful Failover:

•

•

•

•

•

•

Smart Tunnels

Port Forwarding

Plugins

Java Applets

IPv6 clientless or Anyconnect sessions

Citrix authentication (Citrix users must reauthenticate after failover)

Note

If failover occurs during an active Cisco IP SoftPhone session, the call remains active because the call session state information is replicated to the standby unit. When the call is terminated, the IP SoftPhone client loses connection with the Cisco CallManager. This occurs because there is no session information for the CTIQBE hangup message on the standby unit. When the IP SoftPhone client does not receive a response back from the Call Manager within a certain time period, it considers the CallManager unreachable and unregisters itself.

For VPN failover, VPN end-users should not have to reauthenticate or reconnect the VPN session in the event of a failover. However, applications operating over the VPN connection could lose packets during the failover process and not recover from the packet loss.

OL-20339-01


57-7


Auto Update Server Support in Failover Configurations


You can use Auto Update Server to deploy software images and configuration files to adaptive security appliances in an Active/Standby failover configuration. To enable Auto Update on an Active/Standby failover configuration, enter the Auto Update Server configuration on the primary unit in the failover pair.

The following restrictions and behaviors apply to Auto Update Server support in failover configurations:

•

•

•

Only single mode, Active/Standby configurations are supported.

When loading a new platform software image, the failover pair stops passing traffic.

•

When using LAN-based failover, new configurations must not change the failover link configuration. If they do, communication between the units will fail.

Only the primary unit will perform the call home to the Auto Update Server. The primary unit must be in the active state to call home. If it is not, the adaptive security appliance automatically fails over to the primary unit.

•

•

•

Only the primary unit downloads the software image or configuration file. The software image or configuration is then copied to the secondary unit.

The interface MAC address and hardware-serial ID is from the primary unit.

The configuration file stored on the Auto Update Server or HTTP server is for the primary unit only.

Auto Update Process Overview

The following is an overview of the Auto Update process in failover configurations. This process assumes that failover is enabled and operational. The Auto Update process cannot occur if the units are synchronizing configurations, if the standby unit is in the failed state for any reason other than SSM card failure, or if the failover link is down.

1.

2.

Both units exchange the platform and ASDM software checksum and version information.

The primary unit contacts the Auto Update Server. If the primary unit is not in the active state, the adaptive security appliance first fails over to the primary unit and then contacts the Auto Update

Server.

3.

4.

The Auto Update Server replies with software checksum and URL information.

If the primary unit determines that the platform image file needs to be updated for either the active or standby unit, the following occurs:

a.

The primary unit retrieves the appropriate files from the HTTP server using the URL from the

Auto Update Server.

b.

The primary unit copies the image to the standby unit and then updates the image on itself.

c.

If both units have new image, the secondary (standby) unit is reloaded first.

–

If hitless upgrade can be performed when secondary unit boots, then the secondary unit becomes the active unit and the primary unit reloads. The primary unit becomes the active unit when it has finished loading.

–

If hitless upgrade cannot be performed when the standby unit boots, then both units reload at the same time.

d.

If only the secondary (standby) unit has new image, then only the secondary unit reloads. The primary unit waits until the secondary unit finishes reloading.

57-8


OL-20339-01



5.

6.

7.

e.

If only the primary (active) unit has new image, the secondary unit becomes the active unit, and the primary unit reloads.

f.

The update process starts again at step 1.

If the adaptive security appliance determines that the ASDM file needs to be updated for either the primary or secondary unit, the following occurs:

a.

The primary unit retrieves the ASDM image file from the HTTP server using the URL provided by the Auto Update Server.

b.

The primary unit copies the ASDM image to the standby unit, if needed.

c.

The primary unit updates the ASDM image on itself.

d.

The update process starts again at step 1.

If the primary unit determines that the configuration needs to be updated, the following occurs:

a.

The primary unit retrieves the configuration file from the using the specified URL.

b.

The new configuration replaces the old configuration on both units simultaneously.

c.

The update process begins again at step 1.

If the checksums match for all image and configuration files, no updates are required. The process ends until the next poll time.

Monitoring the Auto Update Process

You can use the

debug auto-update client

or

debug fover cmd-exe

commands to display the actions performed during the Auto Update process. The following is sample output from the

debug auto-update client

command. Run

debug

commands from a terminal session.

Auto-update client: Sent DeviceDetails to /cgi-bin/dda.pl of server 192.168.0.21

Auto-update client: Processing UpdateInfo from server 192.168.0.21

Component: asdm, URL: http://192.168.0.21/asdm.bint, checksum:

0x94bced0261cc992ae710faf8d244cf32

Component: config, URL: http://192.168.0.21/config-rms.xml, checksum:

0x67358553572688a805a155af312f6898

Component: image, URL: http://192.168.0.21/cdisk73.bin, checksum:

0x6d091b43ce96243e29a62f2330139419

Auto-update client: need to update img, act: yes, stby yes name ciscoasa(config)# Auto-update client: update img on stby unit...

auto-update: Fover copyfile, seq = 4 type = 1, pseq = 1, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 501, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 1001, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 1501, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 2001, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 2501, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 3001, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 3501, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 4001, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 4501, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 5001, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 5501, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 6001, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 6501, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 7001, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 7501, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 8001, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 8501, len = 1024 auto-update: Fover copyfile, seq = 4 type = 1, pseq = 9001, len = 1024


OL-20339-01 57-9


Failover Health Monitoring

auto-update: Fover file copy waiting at clock tick 6129280 fover_parse: Rcvd file copy ack, ret = 0, seq = 4 auto-update: Fover filecopy returns value: 0 at clock tick 6150260, upd time 145980 msecs

Auto-update client: update img on active unit...

fover_parse: Rcvd image info from mate auto-update: HA safe reload: reload active waiting with mate state: 20 auto-update: HA safe reload: reload active waiting with mate state: 20 auto-update: HA safe reload: reload active waiting with mate state: 20 auto-update: HA safe reload: reload active waiting with mate state: 20 auto-update: HA safe reload: reload active waiting with mate state: 20 auto-update: HA safe reload: reload active waiting with mate state: 20 auto-update: HA safe reload: reload active waiting with mate state: 20 auto-update: HA safe reload: reload active waiting with mate state: 20 auto-update: HA safe reload: reload active waiting with mate state: 20 auto-update: HA safe reload: reload active waiting with mate state: 20 auto-update: HA safe reload: reload active waiting with mate state: 20 auto-update: HA safe reload: reload active waiting with mate state: 20 auto-update: HA safe reload: reload active waiting with mate state: 20 auto-update: HA safe reload: reload active waiting with mate state: 20 auto-update: HA safe reload: reload active waiting with mate state: 20

Beginning configuration replication: Sending to mate.

auto-update: HA safe reload: reload active waiting with mate state: 50 auto-update: HA safe reload: reload active waiting with mate state: 50 auto-update: HA safe reload: reload active waiting with mate state: 80

Sauto-update: HA safe reload: reload active unit at clock tick: 6266860

Auto-update client: Succeeded: Image, version: 0x6d091b43ce96243e29a62f2330139419

The following system log message is generated if the Auto Update process fails:

%ASA4-612002: Auto Update failed:

file

version:

version

reason:

reason

The

file

is “image”, “asdm”, or “configuration”, depending on which update failed. The

version

is the version number of the update. And the

reason

is the reason the update failed.


The adaptive security appliance monitors each unit for overall health and for interface health. See the following sections for more information about how the adaptive security appliance performs tests to determine the state of each unit:

•

Unit Health Monitoring, page 57-11

•

Interface Monitoring, page 57-11

57-10


OL-20339-01



Unit Health Monitoring

The adaptive security appliance determines the health of the other unit by monitoring the failover link.

When a unit does not receive three consecutive hello messages on the failover link, the unit sends interface hello messages on each interface, including the failover interface, to validate whether or not the peer interface is responsive. The action that the adaptive security appliance takes depends upon the response from the other unit. See the following possible actions:

•

If the adaptive security appliance receives a response on the failover interface, then it does not fail over.

•

•

If the adaptive security appliance does not receive a response on the failover link, but it does receive a response on another interface, then the unit does not failover. The failover link is marked as failed.

You should restore the failover link as soon as possible because the unit cannot fail over to the standby while the failover link is down.

If the adaptive security appliance does not receive a response on any interface, then the standby unit switches to active mode and classifies the other unit as failed.

You can configure the frequency of the hello messages and the hold time before failover occurs. A faster poll time and shorter hold time speed the detection of unit failures and make failover occur more quickly, but it can also cause “false” failures due to network congestion delaying the keepalive packets.

Interface Monitoring

You can monitor up to 250 interfaces divided between all contexts. You should monitor important interfaces. For example, you might configure one context to monitor a shared interface. (Because the interface is shared, all contexts benefit from the monitoring.)

When a unit does not receive hello messages on a monitored interface for half of the configured hold time, it runs the following tests:

1.

Link Up/Down test—A test of the interface status. If the Link Up/Down test indicates that the interface is operational, then the adaptive security appliance performs network tests. The purpose of these tests is to generate network traffic to determine which (if either) unit has failed. At the start of each test, each unit clears its received packet count for its interfaces. At the conclusion of each test, each unit looks to see if it has received any traffic. If it has, the interface is considered operational.

If one unit receives traffic for a test and the other unit does not, the unit that received no traffic is considered failed. If neither unit has received traffic, then the next test is used.

2.

3.

Network Activity test—A received network activity test. The unit counts all received packets for up to 5 seconds. If any packets are received at any time during this interval, the interface is considered operational and testing stops. If no traffic is received, the ARP test begins.

ARP test—A reading of the unit ARP cache for the 2 most recently acquired entries. One at a time, the unit sends ARP requests to these machines, attempting to stimulate network traffic. After each request, the unit counts all received traffic for up to 5 seconds. If traffic is received, the interface is considered operational. If no traffic is received, an ARP request is sent to the next machine. If at the end of the list no traffic has been received, the ping test begins.

4.

Broadcast Ping test—A ping test that consists of sending out a broadcast ping request. The unit then counts all received packets for up to 5 seconds. If any packets are received at any time during this interval, the interface is considered operational and testing stops.

If an interface has IPv4 and IPv6 addresses configured on it, the adaptive security appliance uses the

IPv4 addresses to perform the health monitoring.

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57-11


Failover Feature/Platform Matrix

If an interface has only IPv6 addresses configured on it, then the adaptive security appliance uses IPv6 neighbor discovery instead of ARP to perform the health monitoring tests. For the broadcast ping test, the adaptive security appliance uses the IPv6 all nodes address (FE02::1).

If all network tests fail for an interface, but this interface on the other unit continues to successfully pass traffic, then the interface is considered to be failed. If the threshold for failed interfaces is met, then a failover occurs. If the other unit interface also fails all the network tests, then both interfaces go into the

“Unknown” state and do not count towards the failover limit.

An interface becomes operational again if it receives any traffic. A failed adaptive security appliance returns to standby mode if the interface failure threshold is no longer met.

Note

If a failed unit does not recover and you believe it should not be failed, you can reset the state by entering the

failover reset

command. If the failover condition persists, however, the unit will fail again.

Failover Feature/Platform Matrix

Table 57-3 shows the failover features supported by each hardware platform.

Table 57-3 Failover Feature Support by Platform

Platform

Cisco ASA 5505 adaptive security appliance

Cisco ASA 5500 series adaptive security appliance

(other than the ASA 5505)

LAN-Based

Failover

Yes

Yes

Stateful

Failover

No

Yes

Active/Standby

Failover

Yes

Yes

Active/Active

Failover

No

Yes

Failover Times by Platform

Table 57-4 shows the minimum, default, and maximum failover times for the Cisco ASA 5500 series

adaptive security appliance.

Table 57-4 Cisco ASA 5500 Series Adaptive Security Appliance Failover Times

Failover Condition Minimum

Active unit loses power or stops normal operation.

800 milliseconds

Active unit main board interface link down.

Active unit 4GE card interface link down.

Active unit IPS or CSC card fails.

Active unit interface up, but connection problem causes interface testing.

500 milliseconds

2 seconds

2 seconds

5 seconds

Default

15 seconds

5 seconds

5 seconds

2 seconds

25 seconds

Maximum

45 seconds

15 seconds

15 seconds

2 seconds

75 seconds

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Failover Messages


When a failover occurs, both adaptive security appliances send out system messages. This section includes the following topics:

•

Failover System Messages, page 57-13

•

•

Debug Messages, page 57-13

SNMP, page 57-13

Failover System Messages

The adaptive security appliance issues a number of system messages related to failover at priority level

2, which indicates a critical condition. To view these messages, see the

Cisco ASA 5500 Series System

Log Messages

guide. To enable logging, see


Note

During switchover, failover logically shuts down and then bring up interfaces, generating syslog 411001 and 411002 messages. This is normal activity.

Debug Messages

To see debug messages, enter the

debug fover

command. See the

Cisco ASA 5500 Series Command

Reference


Note

Because debugging output is assigned high priority in the CPU process, it can drastically affect system performance. For this reason, use the

debug fover

commands only to troubleshoot specific problems or during troubleshooting sessions with Cisco TAC.

SNMP

To receive SNMP syslog traps for failover, configure the SNMP agent to send SNMP traps to SNMP management stations, define a syslog host, and compile the Cisco syslog MIB into your SNMP

management station. See Chapter 73, “Configuring SNMP”


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57-13



57-14


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C H A P T E R

58

Using the

High Availability and Scalability Wizard

The High Availability and Scalability Wizard guides you through configuring failover with high availability and configuring VPN cluster load balancing. This chapter includes the following sections:

•

Information About the High Availability and Scalability Wizard, page 58-1

•

•

•

•

•

Licensing Requirements for the High Availability and Scalability Wizard, page 58-1

Prerequisites for the High Availability and Scalability Wizard, page 58-2


Configuring Failover with the High Availability and Scalability Wizard, page 58-2

•

Configuring VPN Cluster Load Balancing with the High Availability and Scalability Wizard, page 58-9

Feature History for the High Availability and Scalability Wizard, page 58-11

Information About the High Availability and Scalability Wizard

For more information about failover, see

Information About Failover and High Availability, page 57-1

.

Licensing Requirements for the High Availability and Scalability

Wizard


Model

All models


Base License for failover only.

ASA 5510, ASA 5520, or ASA 5540 Plus License with 3DES or AES active for VPN cluster load balancing. The security appliance checks for the existence of this license before enabling load balancing. If it does not detect an active 3DES license or AES license, the security appliance prevents the enabling of load balancing and internal configuration of 3DES by the load balancing system (unless the license permits this usage).


58-1 OL-20339-01

Chapter 58 Using the High Availability and Scalability Wizard

Prerequisites for the High Availability and Scalability Wizard

Prerequisites for the High Availability and Scalability Wizard

To complete the High Availability and Scalability Wizard, make sure that you have the following information available:

•

LAN failover settings and stateful failover settings, including the following:

–

–

Interface name

Active IP address of the primary unit and secondary unit

•

–

–

Subnet mask of the primary unit and secondary unit

Logical name

–

Role (either primary or secondary)

A 32-character shared key in hexadecimal format (optional) for encrypted communicatoin on the failover link







IPv6 Guidelines

IPv6 addresses are supported for data and failover interfaces.


•

Supports the ASA 5510, 5520, 5540, 5550, and 5580.

Configuring Failover with the High Availability and Scalability

Wizard

You can configure either Active/Active or Active/Standby failover with the High Availability and

Scalability Wizard. This section explains how to use the wizard and contains the following topics:

•

Accessing the High Availability and Scalability Wizard, page 58-3

•

•

•

Configuring Active/Active Failover with the High Availability and Scalability Wizard, page 58-3

Configuring Active/Standby Failover with the High Availability and Scalability Wizard, page 58-4

High Availability and Scalability Wizard Screens, page 58-5

58-2


OL-20339-01


Configuring Failover with the High Availability and Scalability Wizard

Accessing the High Availability and Scalability Wizard

From the ASDM main application window, access the High Availability and Scalability Wizard by choosing one of the following:

•

Wizards > High Availability and Scalability Wizard

• Configuration > Device Management > High Availability > HA/Scalability Wizard

, and then click

Launch High Availability and Scalability Wizard

.

To move to the next screen of the wizard, click

Next

. You must complete the required fields of each screen before you may proceed to the next one.

To return to a previous screen of the wizard, click

Back

. If settings added in later screens of the wizard are not affected by the changes that you made to an earlier screen, that information remains on the screen as you proceed through the wizard again. You do not need to reenter it.

To leave the wizard at any time without saving any changes, click

Cancel

.

To send configuration settings to the adaptive security appliance in the Summary screen of the wizard, click

Finish

.

To obtain additional online information, click

Help

.

Configuring Active/Active Failover with the High Availability and Scalability

Wizard

The following procedure provides a high-level overview for configuring Active/Active failover using the

High Availability and Scalability Wizard. Each step in the procedure corresponds to a wizard screen.

Click

Next

after completing each step, except for the last one, before proceeding to the next step. Each step also includes a reference to additional information that you may need to complete the step.

Step 1

Step 2

Step 3

Step 4

Step 5

In the Configuration Type screen, click

Configure Active/Active failover

.

See

Configuration Type, page 58-5 for more information about this screen.

Enter the IP address of the failover peer in the Failover Peer Connectivity and Compatibility Check screen. Click

Test Compatibility

. You cannot move to the next screen until all compatibility tests have been passed.

See

Failover Peer Connectivity and Compatibility Check, page 58-6 for more information about this

screen.

If the adaptive security appliance or the failover peer are in single context mode, change them to multiple context mode in the Change Device to Multiple Mode screen. When you change the adaptive security appliance to multiple context mode, it reboots. ASDM automatically reestablishes communication with the adaptive security appliance when it has finished rebooting.

See

Change a Device to Multiple Mode, page 58-6

for more information about this screen.

Assign security contexts to failover groups in the Context Configuration screen. You can add and delete contexts in this screen.

See

Security Context Configuration, page 58-7


Define the Failover Link in the Failover Link Configuration screen.

See

Failover Link Configuration, page 58-7 for more information about this screen.

OL-20339-01


58-3



Step 6

Step 7

Step 8

Step 9

(Not available on the ASA 5505 adaptive security appliance) Define the Stateful Failover link in the State

Link Configuration screen.

See

State Link Configuration, page 58-7


Add standby addresses to the adaptive security appliance interfaces in the Standby Address

Configuration screen.

See

Standby Address Configuration, page 58-8


Review your configuration in the Summary screen. If necessary, click

Back

to return to a previous screen and make changes.

See

Summary, page 58-9 for more information about this screen.

Click

Finish

.

The failover configuration is sent to the adaptive security appliance and to the failover peer.

Configuring Active/Standby Failover with the High Availability and Scalability

Wizard

The following procedure provides a high-level overview for configuring Active/Standby failover using the High Availability and Scalability Wizard. Each step in the procedure corresponds to a wizard screen.

Click

Next


Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7


Configure Active/Standby failover

.

See


Enter the IP address of the failover peer on the Failover Peer Connectivity and Compatibility Check screen. Click

Test Compatibility

. You cannot move to the next screen until all compatibility tests have been passed.

See

Failover Peer Connectivity and Compatibility Check, page 58-6


Define the Failover Link in the Failover Link Configuration screen.

See

Failover Link Configuration, page 58-7


(Not available on the ASA 5505 adaptive security appliance) Define the Stateful Failover link in the State

Link Configuration screen.

See



Add standby addresses to the adaptive security appliance interfaces in the Standby Address

Configuration screen.

See




Back

to go to a previous screen and make changes.

See

Summary, page 58-9 for more information about this screen.

Click

Finish

.

58-4


OL-20339-01



The failover configuration is sent to the adaptive security appliance and to the failover peer.

High Availability and Scalability Wizard Screens

The High Availability and Scalability Wizard guides you through a step-by-step process of creating either an Active/Active failover configuration, an Active/Standby failover configuration, or a VPN

Cluster Load Balancing configuration.

As you go through the wizard, screens appear according to the type of failover that you are configuring and the hardware platform that you are using.


•

Configuration Type, page 58-5

•

•

•

•

•

•

•

•

Failover Peer Connectivity and Compatibility Check, page 58-6

Change a Device to Multiple Mode, page 58-6

Security Context Configuration, page 58-7

Failover Link Configuration, page 58-7



VPN Cluster Load Balancing Configuration, page 58-9

Summary, page 58-9

Configuration Type

The Configuration Type screen lets you select the type of failover or VPN cluster load balancing to configure. The Firewall Hardware/Software Profile area shows the following

display-only

information:

•

Hardware model number of the adaptive security appliance.

•

•

Number of interfaces available on the adaptive security appliance.

Number of modules installed on the adaptive security appliance.

•

•

•

Version of the platform software on the adaptive security appliance.

Type of failover license installed on the device. You may need to purchase an upgraded license to configure failover.

•

Firewall mode (routed or transparent) and the context mode (single or multiple).

To choose the type of failover configuration that you want, click one of the following options:

•

•

Configure Active/Active Failover

for Active/Active failover.

Configure Active/Standby Failover

for Active/Standby failover.

Configure VPN Cluster Load Balancing

to participate in VPN load balancing as part of a cluster.

OL-20339-01


58-5



Failover Peer Connectivity and Compatibility Check

The Failover Peer Connectivity and Compatibility Check screen lets you verify that the selected failover peer is reachable and compatible with the current unit. If any of the connectivity and compatibility tests fail, you must correct the problem before you can proceed with the wizard.

To check failover peer connectivity and compatibility, perform the following steps:

Step 1

Step 2

•

•

•

Enter the IP address of the peer unit. This address does not have to be the failover link address, but it must be an interface that has ASDM access enabled on it. The field accepts both IPv4 and IPv6 addresses.

Click

Next

to perform the following connectivity and compatibility tests:

•

Connectivity test from this ASDM to the peer unit

•

•

•

Connectivity test from this firewall device to the peer firewall device

Hardware compatibility test for the platform

Software version compatibility

Failover license compatibility

Firewall mode compatibility (routed or transparent)

Context mode compatibility (single or multiple)

Change a Device to Multiple Mode

The Change Device to Multiple Mode dialog box appears

only

for an Active/Active failover configuration. Active/Active failover requires that the adaptive security appliance be in multiple context mode. This dialog box lets you convert a adaptive security appliance in single context mode to multiple context mode.

When you convert from single context mode to multiple context mode, the adaptive security appliance creates the system configuration and the admin context from the current running configuration. The admin context configuration is stored in the admin.cfg file. The conversion process does not save the previous startup configuration, so if the startup configuration differed from the running configuration, those differences are lost.

Converting the adaptive security appliance from single context mode to multiple context mode causes the adaptive security appliance and its peer to reboot. However, the High Availability and Scalability

Wizard restores connectivity with the newly created admin context and reports the status in the Devices

Status field in this dialog box.

Note

You must convert both the current adaptive security appliance and its peer to multiple context mode before you can proceed.

To change the current adaptive security appliance to multiple context mode, perform the following steps:

Step 1

Step 2

Click

Change

device

To Multiple Context

, where

device

is the hostname of the adaptive security appliance.

Repeat this step for the peer adaptive security appliance.

58-6


OL-20339-01



The status of the adaptive security appliance appears during conversion to multiple context mode.

Security Context Configuration

The Security Context Configuration screen appears

only

for an Active/Active configuration, and lets you assign security contexts to failover groups. It displays the name of currently configured security contexts, lets you add new ones, and change or remove existing ones as needed. In addition, it displays the failover group number to which the context is assigned and lets you change the failover group as needed. Although you can create security contexts in this screen, you cannot assign interfaces to those contexts or configure other properties for them. To configure context properties and assign interfaces to a context, choose

System > Security Contexts

.

Failover Link Configuration

The Failover Link Configuration screen appears

only

if you are configuring LAN-based failover.

To configure LAN-based failover, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Choose the LAN interface to use for failover communication from the drop-down list.

Enter a name for the interface.

Enter the IP address used for the failover link on the unit that has failover group 1 in the active state.

This field accepts an IPv4 or IPv6 address.

Enter the IP address used for the failover link on the unit that has failover group 1 in the standby state.


Enter or choose a subnet mask (IPv4 addresses or a prefix (IPv6 Addresses) for the Active IP and

Standby IP addresses.

(For ASA 5505 only) Choose the switch port from the drop-down list, which includes the current VLAN assigned to each switch port and any name associated with the VLAN. Because a default VLAN exists for every switch port, do not choose VLAN 1 for the inside port, because one less inside port will be available for another use.

Note

To provide sufficient bandwidth for failover, do not use trunks or PoE for failover.

Step 7

(Optional) Enter the secret key used to encrypt failover communication. If you leave this field blank, failover communication, including any passwords or keys in the configuration that are sent during command replication, will be in clear text.

State Link Configuration

Note

The State Link Configuration screen does not appear on the ASA 5505.

OL-20339-01


58-7



The State Link Configuration screen lets you enable and disable Stateful Failover, and configure Stateful

Failover link properties.

To enable Stateful Failover, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

To pass state information across the LAN-based failover link, click

Use the LAN link as the State Link

.

To disable Stateful Failover, click

Disable Stateful Failover

.

To configure an unused interface as the Stateful Failover interface, click

Configure another interface for Stateful failover

.

Choose the interface to use for Stateful Failover communication from the drop-down list.

Enter the name for the Stateful Failover interface.

Enter the IP address for the Stateful Failover link on the unit that has failover group 1 in the active state.


Enter the IP address for the Stateful Failover link on the unit that has failover group 1 in the standby state. This field accepts an IPv4 or IPv6 address.

Enter or choose a subnet mask (IPv4 addresses or a prefix (IPv6 Addresses) for the Active IP and

Standby IP addresses.

Standby Address Configuration

Use the Standby Address Configuration screen to assign standby IP addresses to the interface on the adaptive security appliance. The interfaces currently configured on the failover devices appear. The interfaces are grouped by context, and the contexts are grouped by failover group.

To assign standby IP addresses to the interface on the adaptive security appliance, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

(For Active/Standby failover) Click the plus sign (+) by a device name to display the interfaces on that device. Click the minus sign (-) by a device name to hide the interfaces on that device.

(For Active/Active failover) Click the plus sign (+) by a device, failover group, or context name to expand the list. Click the minus sign (-) by a device, failover group, or context name to collapse the list.

Double-click the

Active IP

field to edit or add an active IP address. Changes to this field also appear in the Standby IP field for the corresponding interface on the failover peer unit. This field accepts IPv4 or

IPv6 addresses.

Double-click the

Standby IP

field to edit or add a standby IP address. Changes to this field also appear in the Active IP field for the corresponding interface on the failover peer unit. This field accepts IPv4 or

IPv6 addresses.

Check the

Is Monitored

check box to enable health monitoring for that interface. Uncheck the check box to disable health monitoring. By default, health monitoring of physical interfaces is enabled, and health monitoring of virtual interfaces is disabled.

Choose the asynchronous group ID from the drop-down list. This setting is only available for physical interface. For virtual interfaces, this field displays “None.”

58-8


OL-20339-01


Configuring VPN Cluster Load Balancing with the High Availability and Scalability Wizard

Summary

The Summary screen displays the results of the configuration steps that you performed in the previous wizard screens.

Verify your settings and click

Finish

to send your configuration to the device. If you are configuring failover, the configuration is also sent to the failover peer. If you need to change a setting, click

Back

to return to the screen that you want to change. Make the change, and click

Next

until you return to the

Summary screen.

Configuring VPN Cluster Load Balancing with the High

Availability and Scalability Wizard

The following procedure provides a high-level overview for configuring VPN cluster load balancing using the High Availability and Scalability Wizard. See

Accessing the High Availability and Scalability

Wizard, page 58-3 , for information about accessing the wizard.

Each step in the procedure corresponds to a wizard screen. Click

Next


Step 1

Step 2

Step 3

Step 4


Configure VPN Cluster Load Balancing

.

See


Configure the VPN load balancing settings in the VPN Cluster Load Balancing Configuration screen.

See

VPN Cluster Load Balancing Configuration, page 58-9 for more information about this screen.


Back

to return to a previous screen and make changes.

See

Summary, page 58-9


Click

Finish

.

The VPN cluster load balancing configuration is sent to the adaptive security appliance.

VPN Cluster Load Balancing Configuration

If you have a remote-client configuration in which you are using two or more adaptive security appliances connected to the same network to handle remote sessions, you can configure these devices to share their session load. This feature is called load balancing, which directs session traffic to the least loaded device, thereby distributing the load among all devices. Load balancing makes efficient use of system resources and provides increased performance and system availability.

Use the VPN Cluster Load Balancing Configuration screen to set required parameters for a device to participate in a load balancing cluster.

Enabling load balancing involves the following:

•

Configuring the load-balancing cluster by establishing a common virtual cluster IP address, UDP port (if necessary), and IPSec shared secret for the cluster. These values are identical for each device in the cluster.


OL-20339-01 58-9


Configuring VPN Cluster Load Balancing with the High Availability and Scalability Wizard

•

Configuring the participating device by enabling load balancing on the device and defining device-specific properties. These values vary from device to device.

Note

Load balancing is effective only on remote sessions initiated with the Cisco VPN client (Version 3.0 and later), the Cisco VPN 3002 hardware client (Version 3.5 and later), or the ASA 5505 configured as an

Easy VPN client. All other clients, including LAN-to-LAN connections, can connect to a adaptive security appliance on which load balancing is enabled, but these clients cannot participate in load balancing.

To implement load balancing, you logically group together two or more devices on the same private

LAN-to-LAN network into a virtual cluster by performing the following steps:

Step 1

Step 2

Step 3

Choose the single IP address that represents the entire virtual cluster. Specify an IP address that is within the public subnet address range shared by all the adaptive security appliances in the virtual cluster.

Specify the UDP port for the virtual cluster in which this device is participating. The default value is

9023. If another application is using this port, enter the UDP destination port number that you want to use for load balancing.

To enable IPSec encryption and ensure that all load-balancing information communicated between the devices is encrypted, check the

Enable IPSec Encryption

check box. You must also specify and verify a shared secret. The adaptive security appliances in the virtual cluster communicate via LAN-to-LAN tunnels using IPSec. To disable IPSec encryption, uncheck the

Enable IPSec Encryption

check box.

Note

When using encryption, you must have previously configured the load balancing inside interface. If that interface is not enabled on the load balancing inside interface, an error message appears when you try to configure cluster encryption.

If the load balancing inside interface is enabled when you configured cluster encryption, but is disabled before you configure the participation of the device in the virtual cluster, an error message appears when you check the

Participate in Load Balancing Cluster

check box, and encryption is not enabled for the cluster.

Step 4

Step 5

Specify the shared secret to between IPSec peers when you enable IPSec encryption. The value that you enter appears as consecutive asterisk characters.

Specify the priority assigned to this device within the cluster. The range is from 1 to 10. The priority indicates the likelihood of this device becoming the virtual cluster master, either at startup or when an existing master fails. The higher the priority set (for example, 10), the more likely that this device will become the virtual cluster master.

Note

If the devices in the virtual cluster are powered up at different times, the first device to be powered up assumes the role of virtual cluster master. Because every virtual cluster requires a master, each device in the virtual cluster checks when it is powered up to ensure that the cluster has a virtual master. If none exists, that device assumes the role. Devices powered up and added to the cluster later become secondary devices. If all the devices in the virtual cluster are powered up simultaneously, the device with the highest priority setting becomes the virtual cluster master.

If two or more devices in the virtual cluster are powered up simultaneously, and both have the highest priority setting, the one with the lowest IP address becomes the virtual cluster master.

Step 6

Specify the name or IP address of the public interface for this device.

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Feature History for the High Availability and Scalability Wizard

Step 7

Step 8

Specify the name or IP address of the private interface for this device.

Check the

Send FQDN to client instead of an IP address when redirecting

check box to have the VPN cluster master send a fully qualified domain name using the host and domain name of the cluster device instead of the outside IP address when redirecting VPN client connections to that cluster device.


Table 58-1


Table 58-1 Feature History for the High Availability and Scalability Wizard

Feature Name

High Availability and Scalability Wizard

IPv6 Address Support in Failover

Configurations

ASDM Releases

5.2(1)

6.2(5)



This features was introduced. The following screens of the High Availability and Scalability Wizard were modified to allow the use of IPv6 Addresses:

•

Failover Peer Connectivity and Compatibility

Check

•

•

•

Failover Link Configuration

State Link Configuration

Standby Address Configuration

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58-12


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C H A P T E R

59


This chapter describes how to configure active/standby failover and includes the following sections:

•

Information About Active/Standby Failover, page 59-1

•

•

•

•

•

•

•

Licensing Requirements for Active/Standby Failover, page 59-5

Prerequisites for Active/Standby Failover, page 59-5


Configuring Active/Standby Failover, page 59-6

Controlling Failover, page 59-12

Monitoring Active/Standby Failover, page 59-14

Feature History for Active/Standby Failover, page 59-17

Information About Active/Standby Failover

This section describes Active/Standby failover and includes the following topics:

•

Active/Standby Failover Overview, page 59-1

•

•

•

•

•

Primary/Secondary Status and Active/Standby Status, page 59-2

Device Initialization and Configuration Synchronization, page 59-2

Command Replication, page 59-3

Failover Triggers, page 59-3

Failover Actions, page 59-4

Active/Standby Failover Overview

Active/Standby failover enables you to use a standby adaptive security appliance to take over the functionality of a failed unit. When the active unit fails, it changes to the standby state while the standby unit changes to the active state. The unit that becomes active assumes the IP addresses (or, for transparent firewall, the management IP address) and MAC addresses of the failed unit and begins passing traffic.

The unit that is now in standby state takes over the standby IP addresses and MAC addresses. Because network devices see no change in the MAC to IP address pairing, no ARP entries change or time out anywhere on the network.


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Chapter 59 Configuring Active/Standby Failover


Note

For multiple context mode, the adaptive security appliance can fail over the entire unit (including all contexts) but cannot fail over individual contexts separately.

Primary/Secondary Status and Active/Standby Status

The main differences between the two units in a failover pair are related to which unit is active and which unit is standby, namely which IP addresses to use and which unit actively passes traffic.

However, a few differences exist between the units based on which unit is primary (as specified in the configuration) and which unit is secondary:

•

The primary unit always becomes the active unit if both units start up at the same time (and are of equal operational health).

•

The primary unit MAC addresses are always coupled with the active IP addresses. The exception to this rule occurs when the secondary unit is active and cannot obtain the primary unit MAC addresses over the failover link. In this case, the secondary unit MAC addresses are used.

Device Initialization and Configuration Synchronization

Configuration synchronization occurs when one or both devices in the failover pair boot. Configurations are always synchronized from the active unit to the standby unit. When the standby unit completes its initial startup, it clears its running configuration (except for the failover commands needed to communicate with the active unit), and the active unit sends its entire configuration to the standby unit.

The active unit is determined by the following:

•

If a unit boots and detects a peer already running as active, it becomes the standby unit.

•

•

If a unit boots and does not detect a peer, it becomes the active unit.

If both units boot simultaneously, then the primary unit becomes the active unit, and the secondary unit becomes the standby unit.

Note

If the secondary unit boots without detecting the primary unit, it becomes the active unit. It uses its own

MAC addresses for the active IP addresses. However, when the primary unit becomes available, the secondary unit changes the MAC addresses to those of the primary unit, which can cause an interruption in your network traffic. To avoid this, configure the failover pair with virtual MAC addresses. See the

“Configuring Virtual MAC Addresses” section on page 59-11


When the replication starts, the adaptive security appliance console on the active unit displays the message “Beginning configuration replication: Sending to mate,” and when it is complete, the adaptive security appliance displays the message “End Configuration Replication to mate.” During replication, commands entered on the active unit may not replicate properly to the standby unit, and commands entered on the standby unit may be overwritten by the configuration being replicated from the active unit.

Avoid entering commands on either unit in the failover pair during the configuration replication process.

Depending upon the size of the configuration, replication can take from a few seconds to several minutes.

Note

The

crypto ca server

command and related sub-commands are not synchronized to the failover peer.

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Note

On the standby unit, the configuration exists only in running memory. To save the configuration to the flash memory on the standby unit, select


from the menu bar. Startup configurations saved on external servers are accessible from either unit over the network and do not need to be saved separately for each unit. Alternatively, you can copy the contexts on disk from the active unit to an external server, and then copy them to disk on the standby unit, where they become available when the unit reloads.

Command Replication

Command replication always flows from the active unit to the standby unit. As you apply your changes to the active unit in ASDM, the associated commands are sent across the failover link to the standby unit.

You do not have to save the active configuration to flash memory to replicate the commands.

Table 59-1

lists the commands that are and are not replicated to the standby unit:

Table 59-1 Command Replication

Command Replicated to the Standby Unit Commands Not Replicated to the Standby Unit

all configuration commands except for the

mode

,

firewall

, and

failover lan unit

commands

copy running-config startup-config

all forms of the

copy

command except for

copy running-config startup-config

all forms of the

write

command except for

write memory delete mkdir rename rmdir crypto ca server debug failover lan unit firewall

and associated sub-commands

write memory

—

—

mode show terminal pager

and

pager

Note

Changes made on the standby unit are not replicated to the active unit. If you enter a command on the standby unit, the adaptive security appliance displays the message

**** WARNING **** Configuration

Replication is NOT performed from Standby unit to Active unit. Configurations are no longer synchronized.

This message displays even when you enter many commands that do not affect the configuration.

Replicated commands are stored in the running configuration. To save replicated commands to the flash memory on the standby unit, select


from the menu bar.

Failover Triggers

The unit can fail if one of the following events occurs:

•

The unit has a hardware failure or a power failure.

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59-3


•

•

•

The unit has a software failure.

Too many monitored interfaces fail.

You force a failover (see

Forcing Failover, page 59-12

).


Failover Actions

In Active/Standby failover, failover occurs on a unit basis. Even on systems running in multiple context mode, you cannot fail over individual or groups of contexts.

Table 59-2 shows the failover action for each failure event. For each failure event, the table shows the

failover policy (failover or no failover), the action taken by the active unit, the action taken by the standby unit, and any special notes about the failover condition and actions.

Table 59-2 Failover Behavior

Failure Event

Active unit failed (power or hardware)

Policy

Failover

Active Action

n/a

Formerly active unit recovers No failover Become standby

Standby unit failed (power or hardware)

No failover Mark standby as failed

Failover link failed during operation

No failover Mark failover interface as failed

Failover link failed at startup No failover Mark failover interface as failed

Stateful Failover link failed No failover No action

Standby Action

Become active

Mark active as failed

No action n/a

Mark failover interface as failed

Become active

No action

Become active

Notes

No hello messages are received on any monitored interface or the failover link.

None.

When the standby unit is marked as failed, then the active unit does not attempt to fail over, even if the interface failure threshold is surpassed.

You should restore the failover link as soon as possible because the unit cannot fail over to the standby unit while the failover link is down.

If the failover link is down at startup, both units become active.

State information becomes out of date, and sessions are terminated if a failover occurs.

None.

Interface failure on active unit above threshold

Interface failure on standby unit above threshold

Failover Mark active as failed

No failover No action Mark standby as failed

When the standby unit is marked as failed, then the active unit does not attempt to fail over even if the interface failure threshold is surpassed.

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Licensing Requirements for Active/Standby Failover

Optional Active/Standby Failover Settings

You can configure the following Active/Standby failover options when you initially configuring failover or after failover has been configured:

•

HTTP replication with Stateful Failover—Allows connections to be included in the state information replication.

•

•

Interface monitoring—Allows you to monitor up to 250 interfaces on a unit and control which interfaces affect your failover.

Interface health monitoring—Enables the security appliance to detect and respond to interface failures more quickly.

•

•

Failover criteria setup—Allows you to specify a specific number of interfaces or a percentage of monitored interfaces that must fail before failover occurs.

Virtual MAC address configuration—Ensures that the secondary unit uses the correct MAC addresses when it is the active unit, even if it comes online before the primary unit.

Licensing Requirements for Active/Standby Failover


Model

ASA 5505

All other models


Security Plus License. (Stateful Failover is not supported.)

Base License.

Prerequisites for Active/Standby Failover

Active/Standby failover has the following prerequisites:

•

•

Both units must be identical security appliances that are connected to each other through a dedicated failover link and, optionally, a Stateful Failover link.

Both units must have the same software configuration and the proper license.

•

Both units must be in the same mode (single or multiple, transparent or routed).




•


•

For multiple context mode, perform all steps in the system execution space unless otherwise noted.


•

Supported in transparent and routed firewall mode.

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IPv6 Guidelines

•

IPv6 failover is supported.


•

Stateful failover is not supported on the Cisco ASA 5505 adaptive security appliance.


The following guidelines and limitations apply for Active/Standby failover:

•

•

To receive packets from both units in a failover pair, standby IP addresses need to be configured on all interfaces.

The standby IP addresses are used on the security appliance that is currently the standby unit, and they must be in the same subnet as the active IP address on the corresponding interface on the active unit.

•

•

•

If you change the console terminal pager settings on the active unit in a failover pair, the active console terminal pager settings change, but the standby unit settings do not. A default configuration issued on the active unit does affect behavior on the standby unit.

When you enable interface monitoring, you can monitor up to 250 interfaces on a unit.

By default, the security appliance does not replicate HTTP session information when Stateful

Failover is enabled. Because HTTP sessions are typically short-lived, and because HTTP clients typically retry failed connection attempts, not replicating HTTP sessions increases system performance without causing serious data or connection loss. The failover replication http command enables the stateful replication of HTTP sessions in a Stateful Failover environment, but it could have a negative impact upon system performance.


This section describes how to configure Active/Standby failover.


•

•

Configuring Failover, page 59-6

Configuring Optional Active/Standby Failover Settings, page 59-9

Configuring Failover

Follow these steps to configure Active/Standby failover on both units.

The speed and duplex settings for the failover interface cannot be changed when Failover is enabled. To change these settings for the failover interface, you must configure them in the Configuration >

Interfaces pane before enabling failover.

Step 1

Step 2

Open the

Configuration > Device Management > Failover > Setup

tab.

Check the Enable Failover checkbox.

Note

Failover is not actually enabled until you apply your changes to the device.

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Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

To encrypt the failover link, do the following:

a.

b.


Use 32 hexadecimal character key

encryption key in the Shared Key box.

Enter the encryption key in the

Shared Key

box.

to enter a hexadecimal value for the

If you checked the Use 32 hexadecimal character key check box, then enter a hexadecimal encryption key. The key must be 32 hexadecimal characters (0-9, a-f).

If the Use 32 hexadecimal character key check box is unchecked, then enter an alphanumeric shared secret. The shared secret can be from 1 to 63 characters. Valid character are any combination of numbers, letters, or punctuation. The shared secret is used to generate the encryption key.

Select the interface to use for the failover link from the

Interface

list. Failover requires a dedicated interface, however you can share the interface with Stateful Failover.

Only unconfigured interfaces or subinterfaces are displayed in this list and can be selected as the LAN

Failover interface. Once you specify an interface as the LAN Failover interface, you cannot edit that interface in the Configuration > Interfaces pane.

Specify the logical name of the interface used for failover communication in the

Logical Name

field.

Specify the active IP address for the interface in the

Active IP

field. The IP address can be either an IPv4 or an IPv6 address. You cannot configure both types of addresses on the failover link interface.

Depending upon the type of address specified for the Active IP, enter a subnet mask (IPv4 addresses) or a prefix length (IPv6 address) for the failover interface in the

Subnet Mask/Prefix Lenght

field. The name of the field changes depending upon the type of address specified in the Active IP field.

Specify the IP address used by the secondary unit to communicate with the primary unit in the

Standby

IP

field. The IP address can be an IPv4 or an IPv6 address.

Select

Primary

or

Secondary

in the

Preferred Role

field to specify whether the preferred role for this adaptive security appliance is as the primary or secondary unit.

(Optional) Configure the Stateful Failover link by doing the following:

Note

Stateful Failover is not available on the ASA 5505 platform. This area does not appear on ASDM running on an ASA 5505 adaptive security appliance.

a.

Specifies the interface used for state communication. You can choose an unconfigured interface or subinterface, the LAN Failover interface, or the Use Named option.

Note

We recommend that you use two separate, dedicated interfaces for the LAN Failover interface and the Stateful Failover interface.

If you choose an unconfigured interface or subinterface, you must supply the Active IP, Subnet

Mask, Standby IP, and Logical Name for the interface.

If you choose the LAN Failover interface, you do not need to specify the Active IP, Subnet Mask,

Logical Name, and Standby IP values; the values specified for the LAN Failover interface are used.

If you choose the Use Named option, the Logical Name field becomes a drop-down list of named interfaces. Choose the interface from this list. The Active IP, Subnet Mask/Prefix Length, and

Standby IP values do not need to be specified. The values specified for the interface are used. Be sure to specify a standby IP address for the selected interface on the Interfaces tab.

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59-7



Note

Because Stateful Failover can generate a large amount of traffic, performance for both Stateful

Failover and regular traffic can suffer when you use a named interface.

Step 11 b.

c.

Specify the IP address for the Stateful Failover interfacein the

Active IP

field. The IP address can be either an IPv4 or an IPv6 address. You cannot configure both types of addresses on the failover link interface. This field is dimmed if the LAN Failover interface or Use Named option is chosen from the Interface drop-down list.

Specify the mask (IPv4 address) or prefix (IPv6 address) for the Stateful Failover interface in the

Subnet Mask/Prefix Length

. This field is dimmed if the LAN Failover interface or Use Named option is selected in the Interface drop-down list.

d.

e.

Specify the interface name used for failover communication in the

Logical Name

field. If you chose the Use Named option in the Interface drop-down list, this field displays a list of named interfaces.

This field is dimmed if the LAN Failover interface is chosen from the Interface drop-down list.

Specify the IP address used by the secondary unit to communicate with the primary unit in the

Standby IP

field. The IP address can be an IPv4 or an IPv6 address. This field is dimmed if the LAN

Failover interface or Use Named option is chosen from the Interface drop-down list.

f.

(Optional) Enable HTTP replication by checking the Enable HTTP Replication check box. This enables Stateful Failover to copy active HTTP sessions to the standby firewall. If you do not allow

HTTP replication, then HTTP connections are disconnected in the event of a failover.

Click

Apply

.

The configuration is saved to the devices in the failover pair.

Configuring Interface Standby Addresses

Configuring standby IP address in ASDM changes depending upon the mode in which the unit is operating. This section includes the following topics:

•

•

Configuring Interface Standby Addresses in Routed Firewall Mode, page 59-8

Configuring the Management Interface Standby Address in Transparent Firewall Mode, page 59-9

Configuring Interface Standby Addresses in Routed Firewall Mode

To configure a standby address for each interface on the adaptive security appliance, follow these steps:

Step 1

Step 2

Open the

Configuration > Device Management > High Availability > Failover > Interfaces

tab.

A list of configured interfaces appears. The IP address for each interface appears in the Active IP

Address column. If configured, the standby IP address for the interface appears in the Standby IP address column. The failover interface and Stateful failover interface do not display IP address; you cannot change those address from this tab.

For each interface that does not have a standby IP address, double-click the Standby IP Address field and do one of the following:

•

Click the

...

button and select an IP address from the list.

59-8


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•

Type an IP address into the field. The address can be an IPv4 or an IPv6 address.

You can also specify whether or not the interface is monitored from this tab. For more information about configuring interface monitoring, see

Disabling and Enabling Interface Monitoring, page 59-9 .

Configuring the Management Interface Standby Address in Transparent Firewall Mode

If you are in multiple context mode, you must perform this procedure in each context.

To configure the management interface standby address on the adaptive security appliance, follow these steps:

Step 1

Step 2

Open the


tab.

A list of configured interfaces appears. Only th e Management interface shows an IP address.

For the Management interface that does not have a standby IP address, double-click the Standby IP

Address field and do one of the following:

•

•

Click the

...

button and select an IP address from the list.

Type an IP address into the field. The address can be an IPv4 or an IPv6 address.

You can also specify whether or not the interface is monitored from this tab. For more information about configuring interface monitoring, see

Disabling and Enabling Interface Monitoring, page 59-9 .

Configuring Optional Active/Standby Failover Settings


•

Disabling and Enabling Interface Monitoring, page 59-9

•

•

Configuring Failover Criteria, page 59-10

Configuring the Unit and Interface Health Poll Times, page 59-11

•

Configuring Virtual MAC Addresses, page 59-11

You can configure the optional Active/Standby failover settings when initially configuring the primary unit in a failover pair or on the active unit in the failover pair after the initial configuration.

Disabling and Enabling Interface Monitoring

You can control which interfaces affect your failover policy by disabling the monitoring of specific interfaces and enabling the monitoring of others. This feature enables you to exclude interfaces attached to less critical networks from affecting your failover policy.

You can monitor up to 250 interfaces on a unit. By default, monitoring physical interfaces is enabled and monitoring subinterfaces is disabled.

Hello messages are exchanged during every interface poll frequency time period between the security appliance failover pair. The failover interface poll time is 3 to 15 seconds. For example, if the poll time is set to 5 seconds, testing begins on an interface if 5 consecutive hellos are not heard on that interface

(25 seconds).

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59-9



Monitored failover interfaces can have the following status:

•

•

•

•

•

•

Unknown—Initial status. This status can also mean the status cannot be determined.

Normal—The interface is receiving traffic.

Testing—Hello messages are not heard on the interface for five poll times.

Link Down—The interface or VLAN is administratively down.

No Link—The physical link for the interface is down.

Failed—No traffic is received on the interface, yet traffic is heard on the peer interface.

To enable or disable health monitoring for specific interfaces on units in single configuration mode, enter one of the following commands. Alternately, for units in multiple configuration mode, you must enter the commands within each security context.

To disable or enable monitoring of an interface, follow these steps:

Step 1

Step 2

Step 3

Open the


tab.

A list of configured interfaces appears. The Monitored column displays whether or not an interface is monitored as part of your failover criteria. If it is monitored, a check appears in the Monitored checkbox.

To disable monitoring of a listed interface, uncheck the

Monitored

checkboxfor the interface.

To enable monitoring of a listed interface, check the

Monitored

checkbox for the interface.

Configuring Failover Criteria

You can specify a specific number of interface or a percentage of monitored interfaces that must fail be fore failover occurs. By default, a single interface failure causes failover.

Use the Configuration > Device Management > High Availability > Criteria tab to define criteria for failover, such as how many interfaces must fail and how long to wait between polls. The hold time specifies the interval to wait without receiving a response to a poll before unit failover.

For information about configuring the hold and poll times, see

Configuring the Unit and Interface Health

Poll Times, page 59-11

.

To configure the interface policy, follow these steps:

Step 1

Step 2

Step 3

Open the

Configuration > Device Management > High Availability > Failover > Criteria

tab.

In the

Interface Policy

area, do one of the following:

•

•

To define a specific number of interfaces that must fail to trigger failover, enter a number from 1 to

250 in the

Number of failed interfaces

field. When the number of failed monitored interfaces exceeds the value you specify, the adaptive security appliance fails over.

To define a percentage of configured interfaces that must fail to trigger failover, enter a percentage in the

Percentage of failed interfaces

field. When the number of failed monitored interfaces exceeds the percentage you set, the adaptive security appliance fails over.

Click

Apply

.

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Configuring the Unit and Interface Health Poll Times

The adaptive security appliance sends hello packets out of each data interface to monitor interface health.

The appliance sends hello messages across the failover link to monitor unit health. If the adaptive security appliance does not receive a hello packet from the corresponding interface on the peer unit for over half of the hold time, then the additional interface testing begins. If a hello packet or a successful test result is not received within the specified hold time, the interface is marked as failed. Failover occurs if the number of failed interfaces meets the failover criteria.

Decreasing the poll and hold times enables the adaptive security appliance to detect and respond to interface failures more quickly, but may consume more system resources. Increasing the poll and hold times prevents the adaptive security appliance from failing over on networks with higher latency.

Step 1

Step 2

Step 3

Step 4

Open the

Configuration > Device Management > High Availability > Failover > Criteria

tab.

To configure the interface poll and hold times, change the following values in the

Failover Poll Times

area:

•

Monitored Interfaces

—The amount of time between polls among interfaces. The range is between

1and 15 seconds or 500 to 999 milliseconds.

•

Interface Hold Time

—Sets the time during which a data interface must receive a hello message on the data interface, after which the peer is declared failed. Valid values are from 5 to 75 seconds.

To configure the unit poll and hold times, change the following values in the

Failover Poll Times

area:

•

•

Unit Failover

—The amount of time between hello messages among units. The range is between 1 and 15 seconds or between 200 and 999 milliseconds.

Unit Hold Time

—Sets the time during which a unit must receive a hello message on the failover link, or else the unit begins the testing process for peer failure. The range is between 1and 45 seconds or between 800 and 999 milliseconds. You cannot enter a value that is less than 3 times the polltime.

Click

Apply

.

Configuring Virtual MAC Addresses

The

Configuration > Device Management > High Availability > MAC Addresses

tab displays the virtual MAC addresses for the interfaces in an Active/Standby failover pair.

Note

This tab is not available on the ASA 5505 platform.

In Active/Standby failover, the MAC addresses for the primary unit are always associated with the active

IP addresses. If the secondary unit boots first and becomes active, it uses the burned-in MAC address for its interfaces. When the primary unit comes online, the secondary unit obtains the MAC addresses from the primary unit. The change can disrupt network traffic.

You can configure virtual MAC addresses for each interface to ensure that the secondary unit uses the correct MAC addresses when it is the active unit, even if it comes online before the primary unit. If you do not specify virtual MAC addresses the failover pair uses the burned-in NIC addresses as the MAC addresses.

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59-11


Controlling Failover

Note

You cannot configure a virtual MAC address for the failover or Stateful Failover links. The MAC and IP addresses for those links do not change during failover.

To configure the virtual MAC address for an interface, follow these steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Open the Configuration > Device Management > High Availability > Failover > MAC Addresses tab.

To edit an existing virtual MAC address entry, double-click the row for the interface whose MAC addresses you want to change. To add a new virtual MAC address entry, click

Add

.

The Add/Edit Interface MAC Address dialog box appears.

Type the new MAC address for the active interface in the

Active MAC Address

field.

Type the new MAC address for the standby interface in the

Standby MAC Address

field.

Click

OK

.

To delete a virtual MAC address entry, follow these steps:

a.

b.

c.

Click the interface to select the table row.

Click

Delete

.

Click

OK

.


This sections describes how to control and monitor failover. This section includes the following topics:

•

Forcing Failover, page 59-12

•

•

Disabling Failover, page 59-12

Restoring a Failed Unit, page 59-13

Forcing Failover

To force the standby unit to become active, follow these steps:

Step 1

Step 2

Open

Monitoring > Properties > Failover > Status

.

Click one of the following buttons:

•

•

Click

Make Active

to make the unit the active unit.

Click

Make Standby

to make the other unit in the pair the active unit.

Disabling Failover

To disable failover, follow these steps:

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OL-20339-01


Step 1

Step 2

Open

Configuration > Device Management > High Availability > Failover

.

Uncheck the

Enable Failover

checkbox.


Restoring a Failed Unit

To restore a failed unit to an unfailed state, follow these steps:

Step 1

Step 2

Open

Monitoring > Properties > Failover > Status

.

Click

Reset Failover

.

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59-13


Monitoring Active/Standby Failover


Use the following screen in the

Monitoring > Properties > Failover

area to monitor Active/Standby failover.

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Screen

M

onitoring > Properties > Failover > Status

Purpose

The Status pane displays the failover state of the system. In single context mode you can control the failover state of the system by doing the following:

•

Forcing a failover.

•

•

Resetting a failed device.

Reloading the standby unit.

See

Controlling Failover, page 59-12

, for more information.

The Failover state of the system field contains the output of the

show failover

command. Refer to


for more information about the displayed output.

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59-15



Screen Purpose

M

onitoring > Properties > Failover > Graphs

The Graphs pane lets you view failover statistics in graph and table form.

In multiple context mode, the Graphs pane is only available in the admin context. The information in the graphs relate to Stateful Failover only.

Available Graphs for

—Lists the types of statistical information available for monitoring. You can choose up to four statistic types to display in one graph window. Double-clicking a statistic type in this field moves it to the Selected Graphs field. Single-clicking a statistic type in this field selects the entry. You can select multiple entries.

The following types of statistics are available in graph or table format in the graph window. They show the number of packets sent to and received from the other unit in the failover pair.

•

RPC services information—Displays the adaptive security appliance

RPC service information.

•

•

•

•

TCP Connection Information—Displays the adaptive security appliance TCP connection information.

UDP Connection Information—Displays the adaptive security appliance UDP connection information.

ARP Table Information—Displays the adaptive security appliance

ARP table information.

L2Bridge Table Information—(Transparent Firewall Mode Only)

Displays the layer 2 bridge table packet counts.

•

•

Xmit Queue—(Single Mode Only) Displays the current, maximum, and total number of packets transmitted.

Receive Queue—(Single Mode Only) Displays the current, maximum, and total number of packets received.

Graph Window

—Shows the graph window name to which you want to add a statistic type. If you have a graph window already open, a new graph window is listed by default. If you want to add a statistic type to an already open graph, select the open graph window name. The statistics already included in the graph window are shown in the Selected Graphs field, to which you can add additional types (up to a maximum of four types per window).

Add

—Click this button to move the selected entries in the Available

Graphs for field to the Selected Graphs field.

Remove—Removes the selected statistic type from the Selected Graphs field.

Selected Graphs

—Shows the statistic types you want to show in the selected graph window. You can include up to four types. Double-clicking a statistic type in this field removes the selected statistic type from the field. Single-clicking a statistic type in this field selects the statistic type.

You can select multiple statistic types.

Show Graphs

—Click this button to display a new or updated graph window with the selected statistics.

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Feature History for Active/Standby Failover


Table 59-3


Table 59-3 Feature History for Optional Active/Standby Failover Settings

Feature Name


IPv6 support for failover added.

Releases

7.0

8.2(2)



The following screens were changed:

Configuration > Device Managment > High

Availability > Failover > Setup


Availability > Failover > Interfaces

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59-18


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C H A P T E R

60


This chapter describes how to configure Active/Active failover and includes the following sections:

•

Information About Active/Active Failover, page 60-1

•

•

•

•

•

•

Licensing Requirements for Active/Active Failover, page 60-6

Prerequisites for Active/Active Failover, page 60-6


Configuring Active/Active Failover, page 60-8

Monitoring Active/Active Failover, page 60-18

Feature History for Active/Active Failover, page 60-19

Information About Active/Active Failover

This section describes Active/Active failover. This section includes the following topics:

•

•

•

•

•

Active/Active Failover Overview, page 60-1

Primary/Secondary Status and Active/Standby Status, page 60-2

Device Initialization and Configuration Synchronization, page 60-3

Command Replication, page 60-3

•

Replicated commands are not saved to the flash memory when replicated to the peer unit. They are added to the running configuration. Failover Triggers, page 60-4

Failover Actions, page 60-5

Active/Active Failover Overview

Active/Active failover is only available to adaptive security appliances in multiple context mode. In an

Active/Active failover configuration, both adaptive security appliances can pass network traffic.

In Active/Active failover, you divide the security contexts on the adaptive security appliance into

failover groups

. A failover group is simply a logical group of one or more security contexts. You can create a maximum of two failover groups. The admin context is always a member of failover group 1.

Any unassigned security contexts are also members of failover group 1 by default.


60-1 OL-20339-01

Chapter 60 Configuring Active/Active Failover


The failover group forms the base unit for failover in Active/Active failover. Interface failure monitoring, failover, and active/standby status are all attributes of a failover group rather than the unit. When an active failover group fails, it changes to the standby state while the standby failover group becomes active. The interfaces in the failover group that becomes active assume the MAC and IP addresses of the interfaces in the failover group that failed. The interfaces in the failover group that is now in the standby state take over the standby MAC and IP addresses.

Note

A failover group failing on a unit does not mean that the unit has failed. The unit may still have another failover group passing traffic on it.

When creating the failover groups, you should create them on the unit that will have failover group 1 in the active state.

Note

Active/Active failover generates virtual MAC addresses for the interfaces in each failover group. If you have more than one Active/Active failover pair on the same network, it is possible to have the same default virtual MAC addresses assigned to the interfaces on one pair as are assigned to the interfaces of the other pairs because of the way the default virtual MAC addresses are determined. To avoid having duplicate MAC addresses on your network, make sure you assign each physical interface a virtual active and standby MAC address.

Primary/Secondary Status and Active/Standby Status

As in Active/Standby failover, one unit in an Active/Active failover pair is designated the primary unit, and the other unit the secondary unit. Unlike Active/Standby failover, this designation does not indicate which unit becomes active when both units start simultaneously. Instead, the primary/secondary designation does two things:

•

•

Determines which unit provides the running configuration to the pair when they boot simultaneously.

Determines on which unit each failover group appears in the active state when the units boot simultaneously. Each failover group in the configuration is configured with a primary or secondary unit preference. You can configure both failover groups be in the active state on a single unit in the pair, with the other unit containing the failover groups in the standby state. However, a more typical configuration is to assign each failover group a different role preference to make each one active on a different unit, distributing the traffic across the devices.

Note

The adaptive security appliance also provides load balancing, which is different from failover. Both failover and load balancing can exist on the same configuration. For information about load balancing, see the

“Configuring Load Balancing” section on page 63-19

.

Which unit each failover group becomes active on is determined as follows:

•

•

When a unit boots while the peer unit is not available, both failover groups become active on the unit.

When a unit boots while the peer unit is active (with both failover groups in the active state), the failover groups remain in the active state on the active unit regardless of the primary or secondary preference of the failover group until one of the following:

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•

–

–

–

A failover occurs.

You manually force a failover.

You configured preemption for the failover group, which causes the failover group to automatically become active on the preferred unit when the unit becomes available.

When both units boot at the same time, each failover group becomes active on its preferred unit after the configurations have been synchronized.

Device Initialization and Configuration Synchronization

Configuration synchronization occurs when one or both units in a failover pair boot. The configurations are synchronized as follows:

•

•

When a unit boots while the peer unit is active (with both failover groups active on it), the booting unit contacts the active unit to obtain the running configuration regardless of the primary or secondary designation of the booting unit.

When both units boot simultaneously, the secondary unit obtains the running configuration from the primary unit.

When the replication starts, the adaptive security appliance console on the unit sending the configuration displays the message “Beginning configuration replication: Sending to mate,” and when it is complete, the adaptive security appliance displays the message “End Configuration Replication to mate.” During replication, commands entered on the unit sending the configuration may not replicate properly to the peer unit, and commands entered on the unit receiving the configuration may be overwritten by the configuration being received. Avoid entering commands on either unit in the failover pair during the configuration replication process. Depending upon the size of the configuration, replication can take from a few seconds to several minutes.

Note

On the unit receiving the configuration, the configuration exists only in running memory. To save the configuration to the flash memory on both units, select

File > Save Running Configuration to flash

from the menu bar in the system execution space on the unit that has failover group 1 in the active state.

Startup configurations saved on external servers are accessible from either unit over the network and do not need to be saved separately for each unit. Alternatively, you can copy the contexts configuration files from the disk on the primary unit to an external server, and then copy them to disk on the secondary unit, where they become available when the unit reloads.

Command Replication

After both units are running, commands are replicated from one unit to the other as follows:

•

Changes entered within a security context are replicated from the unit on which the security context appears in the active state to the peer unit.

Note

A context is considered in the active state on a unit if the failover group to which it belongs is in the active state on that unit.

•

Changes entered in the system execution space are replicated from the unit on which failover group

1 is in the active state to the unit on which failover group 1 is in the standby state.

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•

Changes entered in the admin context are replicated from the unit on which failover group 1 is in the active state to the unit on which failover group 1 is in the standby state.

Failure to enter the changes on the appropriate unit for command replication to occur causes the configurations to be out of synchronization. Those changes may be lost the next time the initial configuration synchronization occurs.

Table 60-1 lists the commands that are and are not replicated to the standby unit.

Table 60-1 Command Replication

Commands Replicated to the Standby Unit Commands Not Replicated to the Standby Unit

all configuration commands except for the

mode

,

firewall

, and

failover lan unit

commands all forms of the

copy

command except for

copy running-config startup-config copy running-config startup-config

all forms of the

write

command except for

write memory debug delete mkdir rename failover lan unit firewall rmdir write memory mode show

Replicated commands are not saved to the flash memory when replicated to the peer unit. They are added to the running configuration.

Failover Triggers

In Active/Active failover, failover can be triggered at the unit level if one of the following events occurs:

•

The unit has a hardware failure.

•

•

The unit has a power failure.

The unit has a software failure.

•


Forcing Failover, page 60-17 ).

Failover is triggered at the failover group level when one of the following events occurs:

•

•

Too many monitored interfaces in the group fail.


Forcing Failover, page 60-17 ).

You configure the failover threshold for each failover group by specifying the number or percentage of interfaces within the failover group that must fail before the group fails. Because a failover group can contain multiple contexts, and each context can contain multiple interfaces, it is possible for all interfaces in a single context to fail without causing the associated failover group to fail.

See the

“Failover Health Monitoring” section on page 57-10

for more information about interface and unit monitoring.

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Failover Actions

In an Active/Active failover configuration, failover occurs on a failover group basis, not a system basis.

For example, if you designate both failover groups as active on the primary unit, and failover group 1 fails, then failover group 2 remains active on the primary unit while failover group 1 becomes active on the secondary unit.

Note

When configuring Active/Active failover, make sure that the combined traffic for both units is within the capacity of each unit.

Table 60-2

shows the failover action for each failure event. For each failure event, the policy (whether or not failover occurs), actions for the active failover group, and actions for the standby failover group are given.

Failover Behavior for Active/Active Failover Table 60-2

Failure Event

A unit experiences a power or software failure

Policy

Failover

Active Group

Action

Become standby

Mark as failed

Standby Group

Action Notes

Become active

Mark active as failed

When a unit in a failover pair fails, any active failover groups on that unit are marked as failed and become active on the peer unit.

Become active None.

Interface failure on active failover group above threshold

Interface failure on standby failover group above threshold

Failover Mark active group as failed

No failover No action

Formerly active failover group recovers

No failover No action

Mark standby group as failed

No action

When the standby failover group is marked as failed, the active failover group does not attempt to fail over, even if the interface failure threshold is surpassed.

Unless failover group preemption is configured, the failover groups remain active on their current unit.

Failover link failed at startup

Stateful Failover link failed

No failover Become active Become active If the failover link is down at startup, both failover groups on both units become active.

No failover No action No action State information becomes out of date, and sessions are terminated if a failover occurs.

Failover link failed during operation No failover n/a n/a Each unit marks the failover interface as failed. You should restore the failover link as soon as possible because the unit cannot fail over to the standby unit while the failover link is down.

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60-5


Licensing Requirements for Active/Active Failover

Optional Active/Active Failover Settings

You can configure the following Active/Standby failover options when you initially configuring failover or after failover has been configured:

•

Failover Group Preemption—Assigns a primary or secondary priority to a failover group to specify on which unit in the failover group becomes active when both units boot simultaneously.

•

•

HTTP replication with Stateful Failover—Allows connections to be included in the state information replication.

Interface monitoring—Allows you to monitor up to 250 interfaces on a unit and control which interfaces affect your failover.

•

•

•

Interface health monitoring—Enables the security appliance to detect and respond to interface failures more quickly.

Failover criteria setup—Allows you to specify a specific number of interfaces or a percentage of monitored interfaces that must fail before failover occurs.

Virtual MAC address configuration—Ensures that the secondary unit uses the correct MAC addresses when it is the active unit, even if it comes online before the primary unit.

Licensing Requirements for Active/Active Failover


Model

ASA 5505

ASA 5510

All other models


No support.

Security Plus License.

Base License.

Prerequisites for Active/Active Failover

In Active/Active failover, both units must have the following:

•

The same hardware model

•

•

•

The same number of interfaces

The same types of interfaces

•

•

•

The same software version, with the same major (first number) and minor (second number) version numbers. However you can use different versions of the software during an upgrade process; for example you can upgrade one unit from Version 7.0(1) to Version 7.9(2) and have failover remain active. We recommend upgrading both units to the same version to ensure long-term compatibility.

(See the

“Performing the Downgrade” section on page 75-20

for more information about upgrading the software on a failover pair.)

The same software configuration

The same mode (multiple context mode)

The proper license

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OL-20339-01






Supported in multiple context mode only.


Supported only in routed and transparent firewall mode.

IPv6 Guidelines

IPv6 failover is supported.


Active/Active failover is not available on the Cisco ASA 5505 adaptive security appliance.


The following features are not supported for Active/Active failover:

•

To receive packets from both units in a failover pair, standby IP addresses need to be configured on all interfaces.

•

•

•

•

•

The standby IP address is used on the security appliance that is currently the standby unit, and it must be in the same subnet as the active IP address.

You can define a maximum number of two failover groups.

Failover groups can only be added to the system context of devices that are configured for multiple context mode.

You can create and remove failover groups only when failover is disabled.

•

•

•

Entering the failover group command puts you in the failover group command mode. The primary, secondary, preempt, replication http, interface-policy, mac address, and polltime interface commands are available in the failover group configuration mode. Use the exit command to return to global configuration mode.

The failover polltime interface, failover interface-policy, failover replication http, and failover MAC address commands have no effect on Active/Active failover configurations. They are overridden by the following failover group configuration mode commands: polltime interface, interface-policy, replication http, and mac address.

When removing failover groups, you must remove failover group 1 last. Failover group1 always contains the admin context. Any context not assigned to a failover group defaults to failover group 1.

You cannot remove a failover group that has contexts explicitly assigned to it.

VPN failover is unavailable. (It is available in Active/Standby failover configurations only.)

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Failover-Multiple Mode, Security Context

The fields displayed on the Failover pane in multiple context mode change depending upon whether the context is in transparent or routed firewall mode.


•

Failover - Routed

•

Failover - Transparent

Failover - Routed

Use this pane to define the standby IP address for each interface in the security context and to specify whether the status of the interface should be monitored.

Fields

•

Interface table—Lists the interfaces on the adaptive security appliance and identifies their active IP address, standby IP address, and monitoring status.

–

Interface Name column—Identifies the interface name.

•

–

–

Active IP column—Identifies the active IP address for this interface.

Standby IP column—Identifies the IP address of the corresponding interface on the standby failover unit.

–

Is Monitored column—Specifies whether this interface is monitored for failure.

Edit—Displays the

Edit Failover Interface Configuration dialog box for the selected interface.

Edit Failover Interface Configuration

Use the Edit Failover Interface Configuration dialog box to define the standby IP address for an interface and to specify whether the status of the interface should be monitored.

Fields

•

Interface Name—Identifies the interface name.

•

Active IP Address—Identifies the IP address for this interface. This field does not appear if an IP address has not been assigned to the interface.

•

•

•

Subnet Mask/Prefix Length—Identifies the mask (for IPv4 addresses) or prefix (for IPv6 addresses) for this interface. This field does not appear if an IP address has not been assigned to the interface.

Standby IP Address—Specifies the IP address of the corresponding interface on the standby failover unit. This field does not appear if an IP address has not been assigned to the interface.

Monitor interface for failure—Specifies whether this interface is monitored for failure. The number of interfaces that can be monitored for the security appliance is 250. Hello messages are exchanged between the security appliance failover pair during every interface poll time period. Monitored failover interfaces can have the following status:

–


–



60-8 OL-20339-01



–

–

–

–


Link Down—The interface is administratively down.



Failover - Transparent

Use this pane to define the standby IP address for the management interface for the security context and to specify whether the status of the interfaces on the security context should be monitored.

Fields

•

Interface—Lists the interfaces for the security context and identifies their monitoring status.

–


•

•

•

–

Is Monitored—Specifies whether this interface is monitored for failure.

Edit—Displays the

Edit Failover Interface Configuration

dialog box for the selected interface.

Management IP Address—Identifies the active and standby management IP addresses for the security context.

–

Active—Identifies the management IP address for the active failover unit.

–

Standby—Specifies the management IP address for the standby failover unit.

Management Netmask—Identifies the mask associated with the management address.

Edit Failover Interface Configuration

Use the Edit Failover Interface Configuration dialog box to specify whether the status of the interface should be monitored.

Fields

•


•

Monitor interface for failure—Specifies whether this interface is monitored for failure. The number of interfaces that can be monitored for the security appliance is 250. Hello messages are exchanged between the security appliance failover pair during every interface poll time period. Monitored failover interfaces can have the following status:

–

–

–

–




Link Down—The interface is administratively down.

–

–



Failover-Multiple Mode, System

This pane includes tabs for configuring the system-level failover settings in the system context of a adaptive security appliance in multiple context mode. In multiple mode, you can configure

Active/Standby or Active/Active failover. Active/Active failover is automatically enabled when you


OL-20339-01 60-9



create failover groups in the device manager. For both types of failover, you need to provide system-level failover settings in the system context, and context-level failover settings in the individual security

contexts. For more information about configuring failover in general, see Chapter 57, “Information

About High Availability.”

.

Seethe following topics for more information:

•

Failover > Setup Tab

•

•

•

Failover > Criteria Tab


Failover > MAC Addresses Tab

Failover > Setup Tab

Use this tab to enable failover on a adaptive security appliance in multiple context mode. You also designate the failover link and the state link, if using Stateful Failover, on this tab.

Note

During a successful failover event on the adaptive security appliance, the interfaces are brought down, roles are switched (IP addresses and MAC addresses are swapped), and the interfaces are brought up again. However, the process is transparent to users. The adaptive security appliance does not send link-down messages or system log messages to notify users that interfaces were taken down during failover (or link-up messages for interfaces brought up by the failover process).

Fields

•

Enable Failover—Checking this check box enables failover and lets you configure a standby adaptive security appliance.

Note

The speed and duplex settings for an interface cannot be changed when Failover is enabled. To change these settings for the failover interface, you must configure them in the Configuration >

Interfaces pane before enabling failover.

•

•

•

Use 32 hexadecimal character key—Check this check box to enter a hexadecimal value for the encryption key in the Shared Key field. Uncheck this check box to enter an alphanumeric shared secret in the Shared Key field.

Shared Key—Specifies the failover shared secret or key for encrypted and authenticated communications between failover pairs.

If you checked the Use 32 hexadecimal character key check box, then enter a hexadecimal encryption key. The key must be 32 hexadecimal characters (0-9, a-f).

If you cleared the Use 32 hexadecimal character key check box, then enter an alphanumeric shared secret. The shared secret can be from 1 to 63 characters. Valid character are any combination of numbers, letters, or punctuation. The shared secret is used to generate the encryption key.

LAN Failover—Contains the fields for configuring LAN Failover.

–

Interface—Specifies the interface used for failover communication. Failover requires a dedicated interface, however, you can use the same interface for Stateful Failover.

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•

–

–

Only unconfigured interfaces or subinterfaces that have not been assigned to a context are displayed in this list and can be selected as the LAN Failover interface. Once you specify an interface as the LAN Failover interface, you cannot edit that interface in the Configuration >

Interfaces pane or assign that interface to a context.

Active IP—Specifies the IP address for the failover interface on the active unit. The IP address can be an IPv4 or an IPv6 address.

Subnet Mask/Prefix Length—Depending upon the type of address specified for the Active IP, enter a subnet mask (IPv4 addresses) or a prefix length (IPv6 address) for the failover interface on the primary and secondary unit.

–

–

–

Preferred Role—Specifies whether the preferred role for this adaptive security appliance is as the primary or secondary unit in a LAN failover.

State Failover—Contains the fields for configuring Stateful Failover.

–

Logical Name—Specifies the logical name of the interface used for failover communication.

Standby IP—Specifies the IP address used by the secondary unit to communicate with the primary unit. The IP address can be an IPv4 or an IPv6 address.

Interface—Specifies the interface used for failover communication. You can choose an unconfigured interface or subinterfaces or the LAN Failover interface.

If you choose the LAN Failover interface, the interface needs enough capacity to handle both the LAN Failover and Stateful Failover traffic. Also, you do not need to specify the Active IP,

Subnet Mask, Logical Name, and Standby IP values; the values specified for the LAN Failover interface are used.

Note

We recommend that you use two separate, dedicated interfaces for the LAN Failover interface and the Stateful Failover interface.

–

–

–

–

–

Active IP—Specifies the IP address for the Stateful Failover interface on the primary unit. This field is dimmed if the LAN Failover interface or Use Named option is chosen from the Interface drop-down list.

Subnet Mask/Prefix Length—Specifies the mask (IPv4 address) or prefix (IPv6 address) for the

Stateful Failover interfaces on the primary and secondary units. This field is dimmed if the LAN

Failover interface or Use Named option is selected in the Interface drop-down list.

Logical Name—Specifies the logical interface used for failover communication. If you chose the Use Named option in the Interface drop-down list, this field displays a list of named interfaces. This field is dimmed if the LAN Failover interface is chosen from the Interface drop-down list.

Standby IP—Specifies the IP address used by the secondary unit to communicate with the primary unit. This field is dimmed if the LAN Failover interface or Use Named option is chosen from the Interface drop-down list.

Enable HTTP replication—Checking this check box enables Stateful Failover to copy active

HTTP sessions to the standby firewall. If you do not allow HTTP replication, then HTTP connections are disconnected at failover. Disabling HTTP replication reduces the amount of traffic on the state link.

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Failover > Criteria Tab

Use this tab to define criteria for failover, such as how many interfaces must fail and how long to wait between polls. The hold time specifies the interval to wait without receiving a response to a poll before unit failover.

Note

If you are configuring Active/Active failover, you do not use this tab to define the interface policy; instead, you define the interface policy for each failover group using the


.

With Active/Active failover, the interface policy settings defined for each failover group override the settings on this tab. If you disable Active/Active failover, then the settings on this tab are used.

Fields

•

Interface Policy—Contains the fields for defining the policy for failover when monitoring detects an interface failure.

–

–

Number of failed interfaces that triggers failover—When the number of failed monitored interfaces exceeds the value you set with this command, then the adaptive security appliance fails over. The range is between 1 and 250 failures.

Percentage of failed interfaces that triggers failover—When the number of failed monitored interfaces exceeds the percentage you set with this command, then the adaptive security appliance fails over.

•

Failover Poll Times—Contains the fields for defining how often hello messages are sent on the failover link, and, optionally, how long to wait before testing the peer for failure if no hello messages are received.

–

Unit Failover—The amount of time between hello messages among units. The range is between

1 and 15 seconds or between 200 and 999 milliseconds.

–

Unit Hold Time—Sets the time during which a unit must receive a hello message on the failover link, or else the unit begins the testing process for peer failure. The range is between 1and 45 seconds or between 800 and 999 milliseconds. You cannot enter a value that is less than 3 times the polltime.

–

Monitored Interfaces—The amount of time between polls among interfaces. The range is between 1and 15 seconds or 500 to 999 milliseconds.

–

Interface Hold Time—Sets the time during which a data interface must receive a hello message on the data interface, after which the peer is declared failed. Valid values are from 5 to 75 seconds.

Failover > Active/Active Tab

Use this tab to enable Active/Active failover on the adaptive security appliance by defining failover groups. In an Active/Active failover configuration, both adaptive security appliances pass network traffic. Active/Active failover is only available to adaptive security appliances in multiple mode.

A failover group is simply a logical group of security contexts. You can create two failover groups on the adaptive security appliance. You must create the failover groups on the active unit in the failover pair.

The admin context is always a member of failover group 1. Any unassigned security contexts are also members of failover group 1 by default.

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Note

During a successful failover event on the adaptive security appliance, the interfaces are brought down, roles are switched (IP addresses and MAC addresses are swapped), and the interfaces are brought up again. However, the process is transparent to users. The adaptive security appliance does not send link-down messages or system log messages to notify users that interfaces were taken down during failover (or link-up messages for interfaces brought up by the failover process).

Note

When configuring Active/Active failover, make sure that the combined traffic for both units is within the capacity of each unit.

Fields

•

Failover Groups—Lists the failover groups currently defined on the adaptive security appliance.

–

–

Group Number—Specifies the failover group number. This number is used when assigning contexts to failover groups.

Preferred Role—Specifies the unit in the failover pair, primary or secondary, on which the failover group appears in the active state when both units start up simultaneously or when the preempt option is specified. You can have both failover groups be in the active state on a single unit in the pair, with the other unit containing the failover groups in the standby state. However, a more typical configuration is to assign each failover group a different role preference to make each one active on a different unit, balancing the traffic across the devices.

–

–

–

–

Preempt Enabled—Specifies whether the unit that is the preferred failover device for this failover group should become the active unit after rebooting.

Preempt Delay—Specifies the number of seconds that the preferred failover device should wait after rebooting before taking over as the active unit for this failover group. The range is between

0 and 1200 seconds.

Interface Policy—Specifies either the number of monitored interface failures or the percentage of failures that are allowed before the group fails over. The range is between 1 and 250 failures or 1 and 100 percent.

Interface Poll Time—Specifies the amount of time between polls among interfaces. The range is between 1 and 15 seconds.

•

•

•

–

Replicate HTTP—Identifies whether Stateful Failover should copy active HTTP sessions to the standby firewall for this failover group. If you do not allow HTTP replication, then HTTP connections are disconnected at failover. Disabling HTTP replication reduces the amount of traffic on the state link. This setting overrides the HTTP replication setting on the Setup tab.

Add—Displays the Add Failover Group dialog box. This button is only enabled if less than 2

failover groups exist. See Add/Edit Failover Group


Edit—Displays the Edit Failover Group dialog box for the selected failover group. See Add/Edit

Failover Group for more information.

Delete—Removes the currently selected failover group from the failover groups table. This button is only enabled if the last failover group in the list is selected.

Add/Edit Failover Group

Use the Add/Edit Failover Group dialog box to define failover groups for an Active/Active failover configuration.

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Fields

•

Preferred Role—Specifies the unit in the failover pair, primary or secondary, on which the failover group appears in the active state. You can have both failover groups be in the active state on a single unit in the pair, with the other unit containing the failover groups in the standby state. However, a more typical configuration is to assign each failover group a different role preference to make each one active on a different unit, balancing the traffic across the devices.

•

Preempt after booting with optional delay of—Checking this check box causes the unit that is the preferred failover device for a failover group to become the active unit after rebooting. Checking this check box also enables the Preempt after booting with optional delay of field in which you can specify a period of time that the device should wait before becoming the active unit.

•

•

Preempt after booting with optional delay of—Specifies the number of seconds that a unit should wait after rebooting before taking over as the active unit for any failover groups for which it is the preferred failover device. The range is between 0 and 1200 seconds.

Interface Policy—Contains the fields for defining the policy for failover when monitoring detects an interface failure. These settings override any interface policy settings on the Criteria tab.

–

–

Number of failed interfaces that triggers failover—When the number of failed monitored interfaces exceeds the value you set with this command, then the adaptive security appliance fails over. The range is between 1 and 250 failures.

Percentage of failed interfaces that triggers failover—When the number of failed monitored interfaces exceeds the percentage you set with this command, then the adaptive security appliance fails over.

•

•

•

•

•

•

Poll time interval for monitored interfaces—The amount of time between polls among interfaces.

The range is between 1 and 15 seconds.

Enable HTTP replication—Checking this check box enables Stateful Failover to copy active HTTP sessions to the standby firewall. If you do not allow HTTP replication, then HTTP connections are disconnected at failover. Disabling HTTP replication reduces the amount of traffic on the state link.

This setting overrides the HTTP replication setting on the Setup tab.

MAC Addresses—Lists physical interfaces on the adaptive security appliance for which an active and standby virtual MAC address has been configured.

–

Physical Interface—Displays the physical interface for which failover virtual MAC addresses are configured.

–

–

Active MAC Address—Displays the MAC address for the interface and failover group on the unit where the failover group is active.

Standby MAC Address—Displays the MAC address for the interface and failover group on the unit where the failover group is in the standby state.

Add—Displays the Add Interface MAC Address dialog box. You cannot assign virtual MAC addresses to the LAN failover and Stateful Failover interfaces. See

Add/Edit Interface MAC

Address for more information.

Edit—Displays the Edit Interface MAC Address dialog box for the selected interface. See

Add/Edit

Interface MAC Address for more information.

Delete—Removes the currently selected interface from the MAC addresses table. There is no confirmation or undo.

60-14


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Add/Edit Interface MAC Address

Use the Add/Edit Interface MAC Address dialog box to define the active and standby virtual MAC addresses for the interfaces in a failover group. If you do not specify a virtual MAC address for an interface, the interface is given a default virtual MAC address as follows:

•

•

Active unit default MAC address: 00a0.c9

physical_port_number

.

failover_group_id

01.

Standby unit default MAC address: 00a0.c9:

physical_port_number

.

failover_group_id

02.

Note

If you have more than one Active/Active failover pair on the same network, it is possible to have the same default virtual MAC addresses assigned to the interfaces on one pair as are assigned to the interfaces of the other pairs because of the way the default virtual MAC addresses are determined. To avoid having duplicate MAC addresses on your network, make sure you assign each physical interface a virtual active and standby MAC address.

These MAC addresses override the physical MAC addresses for the interface.

Fields

•

Physical Interface—Specifies the physical interface for which you are defining failover virtual MAC addresses. Because the MAC addresses do not change for the LAN failover and Stateful Failover interfaces during failover, you cannot choose these interfaces.

•

MAC Addresses—Contains the fields for specifying the active and standby virtual MAC addresses for the interface.

–

–

Active Interface—Specifies the MAC address for the interface and failover group on the unit where the failover group is active. Each interface may have up to two MAC addresses, one for each failover group, which override the physical MAC address. Enter the MAC address in hexadecimal format (for example, 0123.4567.89AB).

Standby Interface—Specifies the MAC address for the interface and failover group on the unit where the failover group is in the standby state. Each interface may have up to two MAC addresses, one for each failover group, which override the physical MAC address. Enter the

MAC address in hexadecimal format (for example, 0123.4567.89AB).

Failover > MAC Addresses Tab

The MAC Addresses tab lets you configure the virtual MAC addresses for the interfaces in an

Active/Standby failover pair.

In Active/Standby failover, the MAC addresses for the primary unit are always associated with the active

IP addresses. If the secondary unit boots first and becomes active, it uses the burned-in MAC address for its interfaces. When the primary unit comes online, the secondary unit obtains the MAC addresses from the primary unit. The change can disrupt network traffic.

You can configure virtual MAC addresses for each interface to ensure that the secondary unit uses the correct MAC addresses when it is the active unit, even if it comes online before the primary unit. If you do not specify virtual MAC addresses, then the failover pair uses the burned-in NIC address as the MAC address.

Note

You cannot configure a virtual MAC address for the failover or state links. The MAC and IP addresses for those links do not change during failover.

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60-15



In Active/Active failover, the MAC addresses configured on this tab are not in effect. Instead, the MAC addresses defined in the failover groups are used.

Fields

•

MAC Addresses—Lists physical interfaces on the adaptive security appliance for which an active and standby virtual MAC address has been configured.

–

–

Physical Interface—Identifies the physical interface for which failover virtual MAC addresses are configured.

Active MAC Address—Identifies the MAC address on the active adaptive security appliance

(usually primary).

•

•

•

–

Standby MAC Address—Identifies the MAC address on the standby adaptive security appliance

(usually secondary).

Add—Displays the

Add/Edit Interface MAC Address dialog box.

Edit—Displays the

Add/Edit Interface MAC Address

dialog box for the selected interface.

Delete—Removes the currently selected interface from the MAC addresses table. There is no confirmation or undo.

Add/Edit Interface MAC Address

Use the Add/Edit Interface MAC Address dialog box to define the active and standby virtual MAC addresses for an interface.

Fields

•

Physical Interface—Specifies the physical interface for which you are defining failover virtual MAC addresses. Because the MAC addresses do not change for the LAN failover and Stateful Failover interfaces during failover, you cannot choose these interfaces.

•

MAC Addresses—Contains the fields for specifying the active and standby virtual MAC addresses for the interface.

–

–

Active Interface—Specifies the MAC address of the interface on the active adaptive security appliance (usually primary). Enter the MAC address in hexadecimal format (for example,

0123.4567.89AB).

Standby Interface—Specifies the MAC address of the interface on the standby adaptive security appliance (usually secondary). Enter the MAC address in hexadecimal format (for example,

0123.4567.89AB).


This sections describes how to control and monitor failover. This section includes the following topics:

•

•

Forcing Failover, page 60-17

Disabling Failover, page 60-17

•

Restoring a Failed Unit or Failover Group, page 60-17

60-16


OL-20339-01


Forcing Failover

To force failover at the unit level, follow these steps:

Step 1

Step 2

Open

System > Monitoring > Failover > System

.

Click one of the following buttons:

•

•

Click

Make Active

to make the unit the active unit.

Click

Make Standby

to make the other unit the active unit.


To force failover at the failover group level, follow these steps:

Step 1

Step 2

Open

System > Monitoring > Failover > Failover Group

#

, where

#

is the number of the failover group you want to control.

Cick one of the following buttons:

•

Click

Make Active

to make the the failover group active on the security appliance.

•

Click

Make Standby

to make the failover group active on the other security appliance.

Disabling Failover

Disabling failover on an Active/Active failover pair causes the failover groups to remain in the active state on whichever unit they are currently active on, no matter which unit they are configured to prefer.

Enter the

no failover

command in the system execution space.

To disable failover, perform the following steps:

Step 1

Step 2

Open the

System > Configuration> Device Setup > High Availability > Failover > Setup

tab.

Clear the

Enable Failover

checkbox.

Restoring a Failed Unit or Failover Group

Restoring a failed unit or failover group moves the unit or failover group from the failed state to the standby state; it does not automatically make the failover group or unit active. Restored units or groups remain in the standby state until made active by failover (forced or natural). An exception is a failover group configured with failover preemption. If previously active, a failover group becomes active if it is configured with preemption and if the unit on which it failed is the preferred unit.

To restore a failed unit to an unfailed state, follow these steps:

Step 1

Open

System > Monitoring > Failover > System

.

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60-17


Monitoring Active/Active Failover

Step 2

Click

Reset Failover

. Clicking this button on the active unit resets the standby unit.

To restore a failed failover group to an unfailed state, follow these steps:

Step 1

Step 2

Open Open

System > Monitoring > Failover > Failover Group

#

, where

#

is the number of the failover group you want to restore.

Click

Reset Failover

.

Monitoring Active/Active Failover

Use the following screens in the Monitoring > Properties > Failover area to monitor Active/Active failover:

•

System, page 60-18

•

Failover Group 1 and Failover Group 2, page 60-19

System

The System pane displays the failover state of the system. You can also control the failover state of the system by:

•

•

•

Toggling the active/standby state of the device.

Resetting a failed device.

Reloading the standby unit.

Fields

Failover state of the system—

Display only

. Displays the failover state of the adaptive security appliance.

The information shown is the same output you would receive from the

show failover

command. Refer to


for more information about the displayed output.

The following actions are available on the System pane:

•

•

•

•

•

Make Active—Click this button to make the adaptive security appliance the active unit in an active/standby configuration. In an active/active configuration, clicking this button causes both failover groups to become active on the adaptive security appliance.

Make Standby—Click this button to make the adaptive security appliance the standby unit in an active/standby pair. In an active/active configuration, clicking this button causes both failover groups to go to the standby state on the adaptive security appliance.

Reset Failover—Click this button to reset a system from the failed state to the standby state. You cannot reset a system to the active state. Clicking this button on the active unit resets the standby unit.

Reload Standby—Click this button to force the standby unit to reload.

Refresh—Click this button to refresh the status information in the Failover state of the system field.

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Feature History for Active/Active Failover

Failover Group 1 and Failover Group 2

The Failover Group 1 and Failover Group 2 panes display the failover state of the selected group.You can also control the failover state of the group by toggling the active/standby state of the group or by resetting a failed group.

Fields

Failover state of Group[

x

]—

Display only

. Displays the failover state of the selected failover group. The information shown is the same as the output you would receive from the

show failover group

command.

You can perform the following actions from this pane:

•

•

•

•

Make Active—Click this button to make the failover group active unit on the adaptive security appliance.

Make Standby—Click this button to force the failover group into the standby state on the adaptive security appliance.

Reset Failover—Click this button to reset a system from the failed state to the standby state. You cannot reset a system to the active state. Clicking this button on the active unit resets the standby unit.

Refresh—Click this button to refresh the status information in the Failover state of the system field.


Table 60-3


Table 60-3 Feature History for Active/Active Failover

Feature Name

Active/Active failover

Releases

7.0

IPv6 Support in failover 8.2(2)


In an Active/Active failover configuration, both adaptive security appliances can pass network traffic.

This feature and the relevant commands were introduced.

The following screens were changed:


Availability > Failover > Setup


Availability > Failover > Interfaces

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60-20


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P

A R T

1 4

Configuring VPN

C H A P T E R

61

SSL VPN Wizard

SSL VPN Connection Type

Clientless, browser-based SSL VPN lets users establish a secure, remote-access VPN tunnel to the adaptive security appliance using a web browser. After authentication, users access a portal page and can access specific, supported internal resources. The network administrator provides access to resources by users on a group basis. Users have no direct access to resources on the internal network.

The Cisco AnyConnect VPN client provides secure SSL connections to the adaptive security appliance for remote users with full VPN tunneling to corporate resouces. Without a previously-installed client, remote users enter the IP address in their browser of an interface configured to accept clientless SSL

VPN connections. The adaptive security appliance downloads the client that matches the operating system of the remote computer. After downloading, the client installs and configures itself, establishes a secure SSL connection and either remains or uninstalls itself (depending on the adaptive security appliance configuration) when the connection terminates. In the case of a previously installed client, when the user authenticates, the adaptive security appliance examines the revision of the client, and upgrades the client as necessary.

Fields

•


—Enables clientless, browser-based connections for specific, supported internal resources through a portal page.

•

Cisco SSL VPN Client (AnyConnect VPN Client)

—Enables SSL VPN client connections for full network access. Enables the adaptive security appliance to download the AnyConnect client to remote users.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—


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Chapter 61 SSL VPN Wizard

SSL VPN Interface

SSL VPN Interface

Provide a Connection name (previously called

tunnel group

), enable an interface for SSL VPN connections, and provide digital certificate information in this window.

Fields

•

Connection Name—Provide a connection name for this group of connection-oriented attributes.

•

SSL VPN Interface—Specify the interface to allow SSL VPN connections.

•

•

•

Digital Certificate—Specify a certificate, if any, that the adaptive security appliance sends to the remote PC.

–

Certificate—Specify the name of the certificate.

Connection Group Settings—You can enable the adaptive security appliance to display a group alias for this connection on the login page.

–

Connection Group Alias—Specify an alias name for the connection.

–

Display Group Alias list at the login page—Enable to display the group alias.

Information—Displays information remote users need for establishing SSL VPN connections and

ASDM connections.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

User Authentication

Specify authentication information on this screen.

Fields

•

Authenticate using a AAA server group—Enable to let the adaptive security appliance contact a remote AAA server group to authenticate the user.

•

AAA Server Group Name—Select a AAA server group from the list of pre-configured groups, or click

New

to create a new group.

•

Authenticate using the local user database—Add new users to the local database stored on the adaptive security appliance.

–

Username—Create a username for the user.

–

–

Password—Create a password for the user.

Confirm Password—Re-type the same password to confirm.

–

Add/Delete—Add or delete the user from the local database.

61-2


OL-20339-01


Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Group Policy

Group Policy

Group policies configure common attributes for groups of users. Create a new group policy or select an existing one to modify.

Fields

•

Create new group policy—Enable to create a new group policy. Provide a name for the new policy.

•

Modify existing group policy—Select an existing group policy to modify.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Bookmark List

Bookmark lists appear on the portal page for Clientless, browser-based connections. SSL VPN client users do not see these bookmarks. Create a new bookmark list on this window.

Fields

•

Bookmark List—Select an existing list or click

Manage

to create a new list, or import or export bookmark lists.

Modes


OL-20339-01


61-3


IP Address Pools and Client Image

Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

IP Address Pools and Client Image

Provide a range of IP addresses to remote SSL VPN users and identify SSL VPN client images to the adaptive security appliance in this window.

Fields

•

IP Address Pool—SSL VPN clients receive new IP addresses when they connect to the adaptive security appliance. Clientless connections do not require new IP addresses. Address Pools define a range of addresses that remote clients can receive.

•

IP Address Pool—Select an existing IP Address Pool, or click

New

to create a new pool.

•

AnyConnect VPN Client Image Location—Identify to the adaptive security appliance files in flash memory that are SSL VPN client images. Click Browse to locate images on your local PC.

–

Location—Provide the path and filename of a valid SSL VPN client image located in flash memory.

–

Download Latest AnyConnect VPN Client form CCO—Click this link to go to the Software

Download page for the latest client image.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Summary

Provides a summary of your selections from the previous wizard windows.

Modes


61-4


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Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Summary

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61-5

Summary


61-6


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C H A P T E R

62

VPN

OL-20339-01

This chapter describes how to configure a basic VPN connection using the IPsec VPN wizard. It includes the following sections:

•

VPN Wizard

•

•

•

•

•

VPN Tunnel Type

Remote Site Peer

IKE Policy

IPsec Rule

•

•

•

•

Hosts and Networks

Remote Access Client

VPN Client Authentication Method and Name


•

•

•

•

•

New Authentication Server Group

User Accounts

Address Pool

Attributes Pushed to Client

IPsec Settings (Optional)

Summary

The adaptive security appliance creates a virtual private network by creating a secure connection across a TCP/IP network (such as the Internet) that users see as a private connection. It can create single-user-to-LAN connections and LAN-to-LAN connections. The secure connection is called a tunnel, and the adaptive security appliance uses tunneling protocols to negotiate security parameters, create and manage tunnels, encapsulate packets, transmit or receive them through the tunnel, and unencapsulate them. The adaptive security appliance functions as a bidirectional tunnel endpoint: it can receive plain packets, encapsulate them, and send them to the other end of the tunnel, where they are unencapsulated and sent to their final destination. It can also receive encapsulated packets, unencapsulate them, and send them to their final destination.

The adaptive security appliance performs the following VPN functions:

•

•

•

Establishes tunnels


Enforces VPN policies


62-1

VPN Wizard

Chapter 62 VPN

•

•

Authenticates users

Authorizes users for specific levels of use and access

Performs accounting functions

•

•

•

•





•

•

Manages data transfer inbound and outbound as a tunnel endpoint or router

The adaptive security appliance invokes various standard protocols to accomplish these functions

VPN Wizard

The VPN wizard lets you configure basic LAN-to-LAN and remote access VPN connections. Use

ASDM to edit and configure advanced features.

Note

The VPN wizard lets you assign either preshared keys or digital certificates for authentication. However, to use certificates, you must enroll with a certification authority and configure a trustpoint prior to using the wizard. Use the ASDM Device Administration > Certificate panes and online Help to accomplish these tasks.

VPN Overview

The adaptive security appliance creates a Virtual Private Network by creating a secure connection across a TCP/IP network (such as the Internet) that users see as a private connection. It can create single-user-to-LAN connections and LAN-to-LAN connections.

For LAN-to-LAN connections using both IPv4 and IPv6 addressing, the security appliance supports

VPN tunnels if both peers are Cisco ASA 5500 series security appliances, and if both inside networks have matching addressing schemes (both IPv4 or both IPv6). This is also true if both peer inside networks are IPv6 and the outside network is IPv6.

The secure connection is called a tunnel, and the adaptive security appliance uses tunneling protocols to negotiate security parameters, create and manage tunnels, encapsulate packets, transmit or receive them through the tunnel, and unencapsulate them. The adaptive security appliance functions as a bidirectional tunnel endpoint: it can receive plain packets, encapsulate them, and send them to the other end of the tunnel where they are unencapsulated and sent to their final destination. It can also receive encapsulated packets, unencapsulate them, and send them to their final destination.

The adaptive security appliance performs the following functions:

•

•

•

•

•

•

Establishes tunnels


Authenticates users





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Chapter 62 VPN

VPN Wizard

•

•


Manages data transfer inbound and outbound as a tunnel endpoint or router

VPN Tunnel Type

Use the VPN Tunnel Type pane to select the type of VPN tunnel to define, remote access or

LAN-to-LAN, and to identify the interface that connects to the remote IPsec peer.

Fields

•

Site-to-Site—Click to create a LAN-to-LAN VPN configuration. Use between two IPsec security gateways, which can include adaptive security appliances, VPN concentrators, or other devices that support site-to-site IPsec connectivity. When you select this option, the VPN wizard displays a series of panes that let you to enter the attributes a site-to-site VPN requires.

The adaptive security appliance supports LAN-to-LAN VPN connections to Cisco or third-party peers when the two peers have IPv4 inside and outside networks (IPv4 addresses on the inside and outside interfaces).

For LAN-to-LAN connections using mixed IPv4 and IPv6 addressing, or all IPv6 addressing, the security appliance supports VPN tunnels if both peers are Cisco ASA 5500 series security appliances, and if both inside networks have matching addressing schemes (both IPv4 or both IPv6).


–

The adaptive security appliances have IPv4 inside networks and the outside network is IPv6

(IPv4 addresses on the inside interfaces and IPv6 addresses on the outside interfaces).

–

–


(IPv6 addresses on the inside interface and IPv4 addresses on the outside interfaces).


(IPv6 addresses on the inside and outside interfaces).

•

•

•

Remote Access—Click to create a configuration that achieves secure remote access for VPN clients, such as mobile users. This option lets remote users securely access centralized network resources.

When you select this option, the VPN wizard displays a series of panes that let you enter the attributes a remote access VPN requires.

VPN Tunnel Interface—Choose the interface that establishes a secure tunnel with the remote IPsec peer. If the adaptive security appliance has multiple interfaces, you need to plan the VPN configuration before running this wizard, identifying the interface to use for each remote IPsec peer with which you plan to establish a secure connection.

Enable inbound IPsec sessions to bypass interface access lists—Enable IPsec authenticated inbound sessions to always be permitted through the security appliance (that is, without a check of the interface access-list statements). Be aware that the inbound sessions bypass only the interface ACLs.

Configured group-policy, user, and downloaded ACLs still apply.

Modes


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62-3

Chapter 62 VPN

VPN Wizard

Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Remote Site Peer

Use the Remote Site Peer pane for the following tasks:

1.

2.

3.

Providing the IP address of the remote IPsec peer that terminates this VPN tunnel.

Selecting and configuring an authentication method.

Creating a connection policy (tunnel group).

Fields

•

Peer IP Address—Type the IP address of the remote IPsec peer that terminates the VPN tunnel. The peer might be another adaptive security appliance, a VPN concentrator, or any other gateway device that supports IPsec.

•

Authentication Method—The remote site peer authenticates either with a preshared key or a certificate.

–

Pre-shared Key—Click to use a preshared key for authentication between the local adaptive security appliance and the remote IPsec peer.

Using a preshared key is a quick and easy way to set up communication with a limited number of remote peers and a stable network. It may cause scalability problems in a large network because each IPsec peer requires configuration information for each peer with which it establishes secure connections.

–

Each pair of IPsec peers must exchange preshared keys to establish secure tunnels. Use a secure method to exchange the preshared key with the administrator of the remote site.

Pre-shared Key—Type the preshared key. Maximum 127 characters.

–

Certificate—Click to use certificates for authentication between the local adaptive security appliance and the remote IPsec peer. To complete this section, you must have previously enrolled with a CA and downloaded one or more certificates to the adaptive security appliance.

Digital certificates are an efficient way to manage the security keys used to establish an IPsec tunnel. A digital certificate contains information that identifies a user or device, such as a name, serial number, company, department or IP address. A digital certificate also contains a copy of the public key.

To use digital certificates, each peer enrolls with a certification authority (CA), which is responsible for issuing digital certificates. A CA can be a trusted vendor or a private CA that you establish within an organization.

When two peers want to communicate, they exchange certificates and digitally sign data to authenticate each other. When you add a new peer to the network, it enrolls with a CA, and none of the other peers require additional configuration.

–

Certificate Signing Algorithm—Displays the algorithm for signing digital certificates, rsa-sig for RSA.

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Chapter 62 VPN

VPN Wizard

•

–

Certificate Name—Choose the name that identifies the certificate the adaptive security appliance sends to the remote peer. This list displays trustpoints with a certificate of the type previously selected in the certificate signing algorithm list.

–

Challenge/response authentication (CRACK)—Provides strong mutual authentication when the client authenticates using a popular method such as RADIUS and the server uses public key authentication. The security appliance supports CRACK as an IKE option in order to authenticate the Nokia VPN Client on Nokia 92xx Communicator Series devices.

Tunnel Group Name—Type a name to create the record that contains tunnel connection policies for this IPsec connection. A connection policy can specify authentication, authorization, and accounting servers, a default group policy, and IKE attributes. A policy that you configure with this VPN wizard specifies an authentication method, and uses the adaptive security appliance Default Group Policy.

By default, ASDM populates this field with the value of the Peer IP address. You can change this name. Maximum 64 characters.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

IKE Policy

IKE, also called Internet Security Association and Key Management Protocol (ISAKMP), is the negotiation protocol that lets two hosts agree on how to build an IPsec Security Association. Each IKE negotiation is divided into two sections called Phase1 and Phase 2.

•

•

Phase 1 creates the first tunnel, which protects later IKE negotiation messages.

Phase 2 creates the tunnel that protects data.

Use the IKE Policy pane to set the terms of the Phase 1 IKE negotiations, which include the following:

•

An encryption method to protect the data and ensure privacy.

•

•

An authentication method to ensure the identity of the peers.

A Diffie-Hellman group to establish the strength of the of the encryption-key-determination algorithm. The adaptive security appliance uses this algorithm to derive the encryption and hash keys.

Fields

•

Encryption—Select the symmetric encryption algorithm the adaptive security appliance uses to establish the Phase 1 SA that protects Phase 2 negotiations. The adaptive security appliance supports the following encryption algorithms:

Algorithm

DES

3DES

Explanation

Data Encryption Standard. Uses a 56-bit key.

Triple DES. Performs encryption three times using a 56-bit key.

OL-20339-01


62-5

VPN Wizard

Chapter 62 VPN

Algorithm

AES-128

AES-192

AES-256

Explanation

Advanced Encryption Standard. Uses a 128-bit key.

AES using a 192-bit key.

AES using a 256-bit key

•

•

The default, 3DES, is more secure than DES but requires more processing for encryption and decryption. Similarly, the AES options provide increased security, but also require increased processing.

Authentication—Choose the hash algorithm used for authentication and ensuring data integrity. The default is SHA. MD5 has a smaller digest and is considered to be slightly faster than SHA. There has been a demonstrated successful (but extremely difficult) attack against MD5. However, the

Keyed-Hash Message Authentication Code (HMAC) version used by the adaptive security appliance prevents this attack.

Diffie-Hellman Group—Choose the Diffie-Hellman group identifier, which the two IPsec peers use to derive a shared secret without transmitting it to each other. The default, Group 2 (1024-bit

Diffie-Hellman), requires less CPU time to execute but is less secure than Group 5 (1536-bit).

Note

The default value for the VPN 3000 Series Concentrator is MD5. A connection between the adaptive security appliance and the VPN Concentrator requires that the authentication method for Phase I and II

IKE negotiations be the same on both sides of the connection.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

IPsec Rule

Use this IPsec Rule pane to select the encryption and authentication methods to use for Phase 2 IKE negotiations, which create the secure VPN tunnel. These values must be exactly the same for both peers.

Fields

•

Encryption—Choose the symmetric encryption algorithm the adaptive security appliance uses to establish the VPN tunnel. The adaptive security appliance uses encryption to protect the data that travels across the tunnel and ensure privacy. Valid encryption methods include the following:

Encryption

Method

DES

3DES

AES-128

Explanation

Data Encryption Standard. Uses a 56-bit key.

Triple DES. Encrypts three times using a 56-bit key.

Advanced Encryption Standard. Uses a 128-bit key.

62-6


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Chapter 62 VPN

VPN Wizard

Encryption

Method

AES-192

AES-256

Explanation

AES using a 192-bit key.

AES using a 256-bit key

•

The default, 3DES, is more secure than DES but requires more processing for encryption and decryption. Similarly, the AES options provide increased security, but also require increased processing.

Authentication—Choose the hash algorithm used for authentication and ensuring data integrity. The default is SHA. MD5 has a smaller digest and is considered to be slightly faster than SHA. There has been a demonstrated successful (but extremely difficult) attack against MD5. However, the

Keyed-Hash Message Authentication Code (HMAC) version used by the adaptive security appliance prevents this attack.

Note

The default value for the VPN 3000 Series Concentrator is MD5. A connection between the adaptive security appliance and the VPN Concentrator requires that the authentication method for Phase I and

Phase II IKE negotiations be the same on both sides of the connection.

•

Enable Perfect Forwarding Secrecy (PFS)—Specify whether to use Perfect Forward Secrecy, and the size of the numbers to use, in generating Phase 2 IPsec keys. PFS is a cryptographic concept where each new key is unrelated to any previous key. In IPsec negotiations, Phase 2 keys are based on Phase 1 keys unless PFS is enabled. PFS uses Diffie-Hellman techniques to generate the keys.

PFS ensures that a session key derived from a set of long-term public and private keys is not compromised if one of the private keys is compromised in the future.

PFS must be enabled on both sides of the connection.

–

Diffie-Hellman Group—Select the Diffie-Hellman group identifier, which the two IPsec peers use to derive a shared secret without transmitting it to each other. The default, Group 2 (1024-bit


Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Hosts and Networks

Use the Hosts and Networks pane to identify local and remote hosts and networks that can use this

LAN-to-LAN IPsec tunnel to send and receive data.

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Chapter 62 VPN

For IPsec to succeed, both peers in the LAN-to-LAN connection must have compatible entries for hosts and networks. The hosts and networks you configure as Local Hosts and Networks in this pane must be configured as Remote Hosts and Networks on the device at the remote site for the LAN-to-LAN connection. The local adaptive security appliance and the remote device must have at least one transform set in common for this LAN-to-LAN connection.

The security appliance supports IPv6 for IKEv1 IPsec LAN-to-LAN VPN connections, including support for both inside and outside networks using the inner and outer IP headers.

Fields

•

Network Type—Choose IPv4 or IPv6.

•

Local networks—Select the local hosts and networks.

•

•

Remote networks—Select the remote hosts and networks.

Exempt ASA side host/network from address translation—Allows traffic to pass through the security appliance without address translation.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Remote Access Client

Use the Remote Access Client pane to identify the type of remote access users this connection serves.

Fields

•

Cisco VPN Client Version 3.x or higher, or other Easy VPN Remote product—Click for IPsec connections, including compatible software and hardware clients other than those named here.

•

Microsoft Windows client using L2TP over IPsec—Click to enable connections from Microsoft

Windows and Microsoft Windows Mobile clients over a public IP network. L2TP uses PPP over

UDP (port 1701) to tunnel the data. Enable one or more of the following PPP authentication protocols:

–

PAP—Passes cleartext username and password during authentication and is not secure.

–

–

CHAP—In response to the server challenge, the client returns the encrypted [challenge plus password] with a cleartext username. This protocol is more secure than the PAP, but it does not encrypt data.

MS-CHAP, Version 1—Similar to CHAP but more secure in that the server stores and compares only encrypted passwords rather than cleartext passwords as in CHAP.

–

–

MS-CHAP, Version 2—Contains security enhancements over MS-CHAP, Version 1.

EAP-Proxy—Enables EAP which permits the adaptive security appliance to proxy the PPP authentication process to an external RADIUS authentication server.

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VPN Wizard

•

Client will send the tunnel group name as username@tunnelgroup—Check to enable the adaptive security appliance to associate different users that are establishing L2TP over IPsec connections with different connection policies. Since each connection policy has its own AAA server group and

IP address pools, users can authenticate through methods specific to their policy.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

VPN Client Authentication Method and Name

Use the VPN Client Authentication Method and Name pane to configure an authentication method and create a connection policy (tunnel group).

Fields

•

Authentication Method—The remote site peer authenticates either with a preshared key or a certificate.

–

Pre-shared Key—Click to use a preshared key for authentication between the local adaptive security appliance and the remote IPsec peer.

Using a preshared key is a quick and easy way to set up communication with a limited number of remote peers and a stable network. It may cause scalability problems in a large network because each IPsec peer requires configuration information for each peer with which it establishes secure connections.

–

–

Each pair of IPsec peers must exchange preshared keys to establish secure tunnels. Use a secure method to exchange the preshared key with the administrator of the remote site.

Pre-shared Key—Type the preshared key.

Certificate—Click to use certificates for authentication between the local adaptive security appliance and the remote IPsec peer. To complete this section, you must have previously enrolled with a CA and downloaded one or more certificates to the adaptive security appliance.

Digital certificates are an efficient way to manage the security keys used to establish an IPsec tunnel. A digital certificate contains information that identifies a user or device, such as a name, serial number, company, department or IP address. A digital certificate also contains a copy of the public key.

–

To use digital certificates, each peer enrolls with a certification authority (CA), which is responsible for issuing digital certificates. A CA can be a trusted vendor or a private CA that you establish within an organization.

When two peers want to communicate, they exchange certificates and digitally sign data to authenticate each other. When you add a new peer to the network, it enrolls with a CA, and none of the other peers require additional configuration.

Certificate Name—Choose the name that identifies the certificate the adaptive security appliance sends to the remote peer.

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Chapter 62 VPN

•

–

Certificate Signing Algorithm—Displays the algorithm for signing digital certificates, rsa-sig for RSA.

–

Challenge/response authentication (CRACK)—Provides strong mutual authentication when the client authenticates using a popular method such as RADIUS and the server uses public key authentication. The security appliance supports CRACK as an IKE option in order to authenticate the Nokia VPN Client on Nokia 92xx Communicator Series devices.

Name—Type a name to create the record that contains tunnel connection policies for this IPsec connection. A connection policy can specify authentication, authorization, and accounting servers, a default group policy, and IKE attributes. A connection policy that you configure with this VPN wizard specifies an authentication method, and uses the adaptive security appliance Default Group

Policy.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Client Authentication

Use the Client Authentication pane to select the method by which the adaptive security appliance authenticates remote users.

Fields

Select one of the following options:

•

•

Authenticate using the local user database—Click to use authentication internal to the adaptive security appliance. Use this method for environments with a small, stable number of users. The next pane lets you create accounts on the adaptive security appliance for individual users.

Authenticate using an AAA server group—Click to use an external server group for remote user authentication.

•

•

AAA Server Group Name—Choose a AAA server group configured previously.

New ...—Click to configure a new AAA server group.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

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Chapter 62 VPN

VPN Wizard

New Authentication Server Group

User the New Authentication Server Group pane to define one or more new AAA servers.

Fields

To configure a new AAA server group that contains just one server, provide the following information:

•

Server Group Name—Type a name for the server group. You associate this name with users whom you want to authenticate using this server.

•

•

•

•

Authentication Protocol—Select the authentication protocol the server uses. Options include

TACACS+, RADIUS, SDI, NT, and Kerberos.

Server IP Address—Type the IP address for the AAA server.

Interface—Choose the adaptive security appliance interface on which the AAA server resides.

Server Secret Key—Type a case-sensitive, alphanumeric keyword of up to 127 characters. The server and adaptive security appliance use the key to encrypt data that travels between them. The key must be the same on both the adaptive security appliance and server. You can use special characters, but not spaces.

•

Confirm Server Secret Key—Type the secret key again.

To add more servers to this new group, or to change other AAA server settings, go to Configuration >

Features > Properties > AAA.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

User Accounts

Use the User Accounts pane to add new users to the adaptive security appliance internal user database for authentication purposes.

•

•

•

Fields

Provide the following information:

•

Use the fields in this section to add a user.

–

Username—Enter the username.

–

–

Password—(Optional) Enter a password.

Confirm Password—(Optional) Reenter the password.

Change user password—Check to change the user password.

User authentication using MSCHAP—Check to use MS-CHAP for user authentication.

Add—Click to add a user to the database after you have entered the username and optional password.


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Chapter 62 VPN

•

•

•

Edit—Click to edit a user that you have added to the database.

Access Restriction—Choose one of the following options:

–

Full access (ASDM, SSH, Telnet, and console)

–

Privilege Level—Choose the correct one from the drop-down list. Administrators are usually assigned 15, the highest available.

CLI login prompt for SSH, Telnet, and console (no ASDM access)

–

No ASDM, SSH, Telnet, or console access

Delete—To remove a user from the database, highlight the appropriate username and click

Delete

.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Address Pool

Use the Address Pool pane to configure a pool of local IP addresses that the adaptive security appliance assigns to remote VPN clients.

Fields

•

Name—Displays the name of the connection policy to which the address pool applies. You set this name in the VPN Client Name and Authentication Method pane.

•

•

•

•

•

Pool Name—Select a descriptive identifier for the address pool.

New...—Click to configure a new address pool.

Range Start Address—Type the starting IP address in the address pool.

Range End Address—Type the ending IP address in the address pool.

Subnet Mask—(Optional) Choose the subnet mask for these IP addresses

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

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VPN Wizard

Attributes Pushed to Client

Use the Attributes Pushed to Client (Optional) pane to have the adaptive security appliance pass information about DNS and WINS servers and the default domain name to remote access clients.

Fields

Provide information for remote access clients to use.

•

Tunnel Group—Displays the name of the connection policy to which the address pool applies. You set this name in the VPN Client Name and Authentication Method pane.

•

•

•

•

•

Primary DNS Server—Type the IP address of the primary DNS server.

Secondary DNS Server—Type the IP address of the secondary DNS server.

Primary WINS Server—Type the IP address of the primary WINS server.

Secondary WINS Server— Type the IP address of the secondary WINS server.

Default Domain Name—Type the default domain name.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

IPsec Settings (Optional)

Use the IPsec Settings (Optional) pane to identify local hosts/networks which do not require address translation. By default, the adaptive security appliance hides the real IP addresses of internal hosts and networks from outside hosts by using dynamic or static Network Address Translation (NAT). NAT minimizes risks of attack by untrusted outside hosts, but may be improper for those who have been authenticated and protected by VPN.

For example, an inside host using dynamic NAT has its IP address translated by matching it to a randomly selected address from a pool. Only the translated address is visible to the outside. Remote VPN clients that attempt to reach these hosts by sending data to their real IP addresses cannot connect to these hosts, unless you configure a NAT exemption rule.

Note

If you want all hosts and networks to be exempt from NAT, configure nothing on this pane. If you have even one entry, all other hosts and networks are subject to NAT.

Fields

•

Host/Network to Be Added—Complete these fields to exempt a particular host or network from

NAT.

–

Interface—Select the name of the interface that connects to the hosts or networks you have selected.

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Chapter 62 VPN

•

•

•

•

–

IP address—Select the IP address of the host or network. Either type the IP address or click the adjacent ... button to view a diagram of the network and select a host or network.

Add—Click to add the host or network the Selected Hosts/Networks list after you have completed the applicable fields.

Selected Hosts/Networks—Displays the hosts and networks that are exempt from NAT. If you want all hosts and networks to be exempt from NAT, leave this list empty.

Enable split tunneling—Select to have traffic from remote access clients destined for the public

Internet sent unencrypted. Split tunneling causes traffic for protected networks to be encrypted, while traffic to unprotected networks is unencrypted. When you enable split tunneling, the adaptive security appliance pushes a list of IP addresses to the remote VPN client after authentication. The remote VPN client encrypts traffic to the IP addresses that are behind the adaptive security appliance. All other traffic travels unencrypted directly to the Internet without involving the adaptive security appliance.

Enable Perfect Forwarding Secrecy (PFS)—Specify whether to use Perfect Forward Secrecy, and the size of the numbers to use, in generating Phase 2 IPsec keys. PFS is a cryptographic concept where each new key is unrelated to any previous key. In IPsec negotiations, Phase 2 keys are based on Phase 1 keys unless PFS is enabled. PFS uses Diffie-Hellman techniques to generate the keys.

PFS ensures that a session key derived from a set of long-term public and private keys is not compromised if one of the private keys is compromised in the future.

PFS must be enabled on both sides of the connection.

–

Diffie-Hellman Group—Select the Diffie-Hellman group identifier, which the two IPsec peers use to derive a shared secret without transmitting it to each other. The default, Group 2 (1024-bit


Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Summary

The Summary pane displays all of the attributes of this VPN LAN-to-LAN connection as configured.

Fields

Back—To make changes, click

Back

until you reach the appropriate pane.

Finish—When you are satisfied with the configuration, click

Finish

. ASDM saves the LAN-to-LAN configuration. After you click

Finish

, you can no longer use the VPN wizard to make changes to this configuration. Use ASDM to edit and configure advanced features.

Cancel—To remove the configuration, click

Cancel

.

Modes


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Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

VPN Wizard

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Chapter 62 VPN

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C H A P T E R

63

Configuring IKE, Load Balancing, and NAC

IKE, also called ISAKMP, is the negotiation protocol that lets two hosts agree on how to build an IPsec security association. To configure the adaptive security appliance for virtual private networks, you set global IKE parameters that apply system wide, and you also create IKE policies that the peers negotiate to establish a VPN connection.

Load balancing distributes VPN traffic among two or more adaptive security appliances in a VPN cluster.

Network Access Control (NAC) protects the enterprise network from intrusion and infection from worms, viruses, and rogue applications by performing endpoint compliance and vulnerability checks as a condition for production access to the network. We refer to these checks as

posture validation.

This chapter describes how to configure IKE, load balancing, and NAC. It includes the following sections:

Setting IKE Parameters

Creating IKE Policies

Configuring IPsec

Configuring Load Balancing

Setting Global NAC Parameters

Configuring Network Admission Control Policies

Setting IKE Parameters

This pane lets you set system wide values for VPN connections. The following sections describe each of the options.

Enabling IKE on Interfaces

You must enable IKE for each interface that you want to use for VPN connections.

Enabling IPsec over NAT-T

NAT-T lets IPsec peers establish both remote access and LAN-to-LAN connections through a NAT device. It does this by encapsulating IPsec traffic in UDP datagrams, using port 4500, thereby providing

NAT devices with port information. NAT-T auto-detects any NAT devices, and only encapsulates IPsec traffic when necessary. This feature is disabled by default.

•

The adaptive security appliance can simultaneously support standard IPsec, IPsec over TCP, NAT-T, and IPsec over UDP, depending on the client with which it is exchanging data.

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Chapter 63 Configuring IKE, Load Balancing, and NAC


•

When both NAT-T and IPsec over UDP are enabled, NAT-T takes precedence.

•

When enabled, IPsec over TCP takes precedence over all other connection methods.

The adaptive security appliance implementation of NAT-T supports IPsec peers behind a single

NAT/PAT device as follows:

•

•

To use NAT-T you must:

•

Open port 4500 on the adaptive security appliance.

•

One LAN-to-LAN connection.

Either a LAN-to-LAN connection or multiple remote access clients, but not a mixture of both.

•

Enable IPsec over NAT-T globally in this pane.

Choose the second or third option for the Fragmentation Policy parameter in the Configuration >

VPN > IPsec > Pre-Fragmentation pane. These options let traffic travel across NAT devices that do not support IP fragmentation; they do not impede the operation of NAT devices that do support IP fragmentation.

Enabling IPsec over TCP

IPsec over TCP enables a VPN client to operate in an environment in which standard ESP or IKE cannot function, or can function only with modification to existing firewall rules. IPsec over TCP encapsulates both the IKE and IPsec protocols within a TCP packet, and enables secure tunneling through both NAT and PAT devices and firewalls. This feature is disabled by default.

Note

This feature does not work with proxy-based firewalls.

IPsec over TCP works with remote access clients. It works on all physical and VLAN interfaces. It is a client to adaptive security appliance feature only. It does not work for LAN-to-LAN connections.

•

•

The adaptive security appliance can simultaneously support standard IPsec, IPsec over TCP,

NAT-Traversal, and IPsec over UDP, depending on the client with which it is exchanging data.

The VPN 3002 hardware client, which supports one tunnel at a time, can connect using standard

IPsec, IPsec over TCP, NAT-Traversal, or IPsec over UDP.

•

When enabled, IPsec over TCP takes precedence over all other connection methods.

You enable IPsec over TCP on both the adaptive security appliance and the client to which it connects.

You can enable IPsec over TCP for up to 10 ports that you specify. If you enter a well-known port, for example port 80 (HTTP) or port 443 (HTTPS), the system displays a warning that the protocol associated with that port will no longer work. The consequence is that you can no longer use a browser to manage the adaptive security appliance through the IKE-enabled interface. To solve this problem, reconfigure the HTTP/HTTPS management to different ports.

You must configure TCP port(s) on the client as well as on the adaptive security appliance. The client configuration must include at least one of the ports you set for the adaptive security appliance.

Determining ID Method

During IKE negotiations the peers must identify themselves to each other. You can choose the identification methods from the following options:

Address

Hostname

Uses the IP addresses of the hosts exchanging ISAKMP identity information.

Uses the fully-qualified domain name of the hosts exchanging ISAKMP identity information (default). This name comprises the hostname and the domain name.

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Key ID

Automatic


Uses the string the remote peer uses to look up the preshared key.

Determines IKE negotiation by connection type:

•

•

IP address for preshared key

Cert DN for certificate authentication.

Disabling Inbound Aggressive Mode Connections

Phase 1 IKE negotiations can use either Main mode or Aggressive mode. Both provide the same services, but Aggressive mode requires only two exchanges between the peers, rather than three. Aggressive mode is faster, but does not provide identity protection for the communicating parties. It is therefore necessary that they exchange identification information prior to establishing a secure SA in which to encrypt in formation. This feature is disabled by default.

Alerting Peers Before Disconnecting

Client or LAN-to-LAN sessions may be dropped for several reasons, such as: a adaptive security appliance shutdown or reboot, session idle timeout, maximum connection time exceeded, or administrator cut-off.

The adaptive security appliance can notify qualified peers (in LAN-to-LAN configurations), VPN

Clients and VPN 3002 hardware clients of sessions that are about to be disconnected, and it conveys to them the reason. The peer or client receiving the alert decodes the reason and displays it in the event log or in a pop-up pane. This feature is disabled by default.

This pane lets you enable the feature so that the adaptive security appliance sends these alerts, and conveys the reason for the disconnect.

Qualified clients and peers include the following:

•

•

•

•

Security appliances with Alerts enabled.

VPN clients running 4.0 or later software (no configuration required).

VPN 3002 hardware clients running 4.0 or later software, and with Alerts enabled.

VPN 3000 concentrators running 4.0 or later software, with Alerts enabled.

Waiting for Active Sessions to Terminate Prior to Reboot

You can schedule a adaptive security appliance reboot to occur only when all active sessions have terminated voluntarily. This feature is disabled by default.

Fields

•

Enable IKE—Shows IKE status for all configured interfaces.

–

Interface—Displays names of all configured adaptive security appliance interfaces.

•

–

–

NAT Transparency—Lets you enable or disable IPsec over NAT-T and IPsec over TCP.

–

Enable IPsec over NAT-T—Choose to enable IPsec over NAT-T.

–

IKE Enabled—Shows whether IKE is enabled for each configured interface.

Enable/Disables—Click to enable or disable IKE for the highlighted interface.

–

NAT Keepalive—Type the number of seconds that can elapse with no traffic before the adaptive security appliance terminates the NAT-T session. The default is 20 seconds. The range is 10 to

3600 seconds (one hour).

Enable IPsec over TCP—Choose to enable IPsec over TCP.

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Creating IKE Policies

•

–

Enter up to 10 comma-separated TCP port values—Type up to 10 ports on which to enable IPsec over TCP. Use a comma to separate the ports. You do not need to use spaces. The default port is 10,000. The range is 1 to 65,635.

Identity to Be Sent to Peer—Lets you set the way that IPsec peers identify themselves to each other.

–

Identity—Choose one of the following methods by which IPsec peers identify themselves:

Address

Hostname

Key ID

Automatic

Uses the IP addresses of the hosts.

Uses the fully-qualified domain names of the hosts. This name comprises the hostname and the domain name.

Uses the string the remote peer uses to look up the preshared key.

Determines IKE negotiation by connection type: IP address for preshared key or cert DN for certificate authentication.

•

•

•

–

Key Id String—Type the alpha-numeric string the peers use to look up the preshared key.

Disable inbound aggressive mode connections—Choose to disable aggressive mode connections.

Alert peers before disconnecting—Choose to have the adaptive security appliance notify qualified

LAN-to-LAN peers and remote access clients before disconnecting sessions.

Wait for all active sessions to voluntarily terminate before rebooting—Choose to have the adaptive security appliance postpone a scheduled reboot until all active sessions terminate.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—


Each IKE negotiation is divided into two sections called Phase1 and Phase 2.

Phase 1 creates the first tunnel, which protects later IKE negotiation messages. Phase 2 creates the tunnel that protects data.

To set the terms of the IKE negotiations, you create one or more IKE policies, which include the following:

•

A unique priority (1 through 65,543, with 1 the highest priority).

•

•

An authentication method, to ensure the identity of the peers.

An encryption method, to protect the data and ensure privacy.

•

•

An HMAC method to ensure the identity of the sender, and to ensure that the message has not been modified in transit.

A Diffie-Hellman group to establish the strength of the of the encryption-key-determination algorithm. The adaptive security appliance uses this algorithm to derive the encryption and hash keys.

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•

A limit for how long the adaptive security appliance uses an encryption key before replacing it.

If you do not configure any IKE policies, the adaptive security appliance uses the default policy, which is always set to the lowest priority, and which contains the e default value for each parameter. If you do not specify a value for a specific parameter, the default value takes effect.

When IKE negotiation begins, the peer that initiates the negotiation sends all of its policies to the remote peer, and the remote peer searches for a match with its own policies, in priority order.

A match between IKE policies exists if they have the same encryption, hash, authentication, and

Diffie-Hellman values, and an SA lifetime less than or equal to the lifetime in the policy sent. If the lifetimes are not identical, the shorter lifetime—from the remote peer policy—applies. If no match exists, IKE refuses negotiation and the IKE SA is not established.

Fields

•

Policies—Displays parameter settings for each configured IKE policy.

–

Priority #—Shows the priority of the policy.

–

–

–

–

Encryption—Shows the encryption method.

Hash—Shows the has algorithm.

D-H Group—Shows the Diffie-Hellman group.

Authentication—Shows the authentication method.

•

–

Lifetime (secs)—Shows the SA lifetime in seconds.

Add/Edit/Delete—Click to add, edit, or delete an IKE policy.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit IKE Policy

Fields

Priority #—Type a number to set a priority for the IKE policy. The range is 1 to 65,543, with 1 the highest priority.

Encryption—Choose an encryption method. This is a symmetric encryption method that protects data transmitted between two IPsec peers.The choices follow: des

3des aes aes-192 aes-256

56-bit DES-CBC. Less secure but faster than the alternatives. The default.

168-bit Triple DES.

128-bit AES.

192-bit AES.

256-bit AES.

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Hash—Choose the hash algorithm that ensures data integrity. It ensures that a packet comes from whom you think it comes from, and that it has not been modified in transit.

sha md5

SHA-1 The default is SHA-1. MD5 has a smaller digest and is considered to

MD5 be slightly faster than SHA-1. A successful (but extremely difficult) attack against MD5 has occurred; however, the HMAC variant IKE uses prevents this attack.

Authentication—Choose the authentication method the adaptive security appliance uses to establish the identity of each IPsec peer. Preshared keys do not scale well with a growing network but are easier to set up in a small network. The choices follow: pre-share rsa-sig crack

Preshared keys.

A digital certificate with keys generated by the RSA signatures algorithm.

IKE Challenge/Response for Authenticated Cryptographic Keys protocol for mobile

IPsec-enabled clients which use authentication techniques other than certificates.

2

5

D-H Group—Choose the Diffie-Hellman group identifier, which the two IPsec peers use to derive a shared secret without transmitting it to each other.

1 Group 1 (768-bit) The default, Group 2 (1024-bit Diffie-Hellman) requires less

CPU time to execute but is less secure than Group 2 or 5.

Group 2 (1024-bit

Group 5 (1536-bit)

Lifetime (secs)—Either choose Unlimited or type an integer for the SA lifetime. The default is 86,400 seconds or 24 hours. With longer lifetimes, the adaptive security appliance sets up future IPsec security associations more quickly. Encryption strength is great enough to ensure security without using very fast rekey times, on the order of every few minutes. We recommend that you accept the default.

Time Measure—Choose a time measure. The adaptive security appliance accepts the following values:.

120 - 86,400 seconds

2 - 1440 minutes

1 - 24 hours

1 day

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

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Assignment Policy

IP addresses make internetwork connections possible. They are like telephone numbers: both the sender and receiver must have an assigned number to connect. But with VPNs, there are actually two sets of addresses: the first set connects client and server on the public network; and once that connection is made, the second set connects client and server through the VPN tunnel.

In adaptive security appliance address management, we are dealing with the second set of IP addresses: those private IP addresses that connect a client with a resource on the private network, through the tunnel, and let the client function as if it were directly connected to the private network. Furthermore, we are dealing only with the private IP addresses that get assigned to clients. The IP addresses assigned to other resources on your private network are part of your network administration responsibilities, not part of adaptive security appliance management.

Therefore, when we discuss IP addresses here, we mean those IP addresses available in your private network addressing scheme, that let the client function as a tunnel endpoint.

The Assignment Policy pane lets you choose a way to assign IP addresses to remote access clients.

Fields

•

Use authentication server—Choose to assign IP addresses retrieved from an authentication server on a per-user basis. If you are using an authentication server (external or internal) that has IP addresses configured, we recommend using this method. Configure AAA servers in the

Configuration > AAA Setup pane.

•

•

Use DHCP— Choose to obtain IP addresses from a DHCP server. If you use DHCP, configure the server in the Configuration > DHCP Server pane.

Use internal address pools—Choose to have the adaptive security appliance assign IP addresses from an internally configured pool. Internally configured address pools are the easiest method of address pool assignment to configure. If you use this method, configure the IP address pools in

Configuration > Remote Access VPN > Network (Client) Access > Address Assignment >

Address Pools pane.

–

Allow the reuse of an IP address __ minutes after it is released—Delays the reuse of an IP address after its return to the address pool. Adding a delay helps to prevent problems firewalls can experience when an IP address is reassigned quickly. By default, this is unchecked, meaning the adaptive security appliance does not impose a delay. If you want one, check the box and enter the number of minutes in the range 1 - 480 to delay IP address reassignment.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

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Address Pools

The IP Pool area shows each configured address pool by name, and with their IP address range, for example: 10.10.147.100 to 10.10.147.177. If no pools exist, the area is empty. The adaptive security appliance uses these pools in the order listed: if all addresses in the first pool have been assigned, it uses the next pool, and so on.

If you assign addresses from a non-local subnet, we suggest that you add pools that fall on subnet boundaries to make adding routes for these networks easier.

Fields

•

Pool Name—Displays the name of each configured address pool.

•

•

•

•

Starting Address—Shows first IP address available in each configured pool.

Ending Address—Shows the last IP address available in each configured pool.

Subnet Mask—Shows the subnet mask for addresses in each configured pool.

Add—Click to add a new address pool.

•

Edit/Delete—Click to edit or delete an already configured address pool.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit IP Pool

These panes let you:

•

Add a new pool of IP addresses from which the adaptive security appliance assigns addresses to clients.

•

Modify an IP address pool that you have previously configured.

The IP addresses in the pool range must not be assigned to other network resources.

Fields

•

Name—Assign an alpha-numeric name to the address pool. Limit 64 characters

•

Starting IP Address—Enter the first IP address available in this pool. Use dotted decimal notation, for example: 10.10.147.100.

•

•

Ending IP Address—Enter the last IP address available in this pool. Use dotted decimal notation, for example: 10.10.147.100.

Subnet Mask—Choose the subnet mask for the IP address pool.

Modes


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Configuring IPsec

Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—


The adaptive security appliance uses IPsec for LAN-to-LAN VPN connections, and provides the option of using IPsec for client-to-LAN VPN connections. In IPsec terminology, a “peer” is a remote-access client or another secure gateway.

Note

The ASA supports LAN-to-LAN IPsec connections with Cisco peers (IPv4 or IPv6), and with third-party peers that comply with all relevant standards.

During tunnel establishment, the two peers negotiate security associations that govern authentication, encryption, encapsulation, and key management. These negotiations involve two phases: first, to establish the tunnel (the IKE SA); and second, to govern traffic within the tunnel (the IPsec SA).

A LAN-to-LAN VPN connects networks in different geographic locations. In IPsec LAN-to-LAN connections, the adaptive security appliance can function as initiator or responder. In IPsec client-to-LAN connections, the adaptive security appliance functions only as responder. Initiators propose SAs; responders accept, reject, or make counter-proposals—all in accordance with configured

SA parameters. To establish a connection, both entities must agree on the SAs.

The adaptive security appliance supports these IPsec attributes:

•

•

•

Main mode for negotiating phase one ISAKMP security associations when using digital certificates for authentication

Aggressive mode for negotiating phase one ISAKMP Security Associations (SAs) when using preshared keys for authentication

Authentication Algorithms:

•

•

•

•

–

–

ESP-MD5-HMAC-128

ESP-SHA1-HMAC-160

Authentication Modes:

–

Preshared Keys

–

X.509 Digital Certificates

Diffie-Hellman Groups 1, 2, and 5.

Encryption Algorithms:

–

AES-128, -192, and -256

–

–

3DES-168

DES-56

–

ESP-NULL

Extended Authentication (XAuth)

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•

•

•

Mode Configuration (also known as ISAKMP Configuration Method)

Tunnel Encapsulation Mode

IP compression (IPCOMP) using LZS

Adding Crypto Maps

This pane shows the currently configured crypto maps, including the IPsec rules. Use it to add, edit, delete and move up, move down, cut, copy, and paste an IPsec rule.

Fields

Note

You cannot edit, delete, or copy an implicit rule. The adaptive security appliance implicitly accepts the traffic selection proposal from remote clients when configured with a dynamic tunnel policy. You can override it by giving a specific traffic selection.

•

•

•

•

•

•

•

•

•

Add—Click to launch the Create IPsec Rule dialog box, where you can configure basic, advanced, and traffic selection parameters for a rule.

Edit—Click to edit an existing rule.

Delete—Click to delete a rule highlighted in the table.

Cut—Deletes a highlighted rule in the table and keeps it in the clipboard for copying.

Copy—Copies a highlighted rule in the table.

Find—Click to enable the Find toolbar where you can specify the parameters of existing rules that you want to find:

–

Filter—Filter the find results by selecting Interface, Source, Destination, Destination Service, or Rule Query, selecting is or contains, and entering the filter parameter. Click ... to launch a browse dialog box that displays all existing entries that you can choose.

Diagram—Displays a diagram that illustrates the highlighted IPsec rule.

Type: Priority—Displays the type of rule (static or dynamic) and its priority.

Traffic Selection

–

#—Indicates the rule number.

–

–

Source—Indicates the IP addresses that are subject to this rule when traffic is sent to the IP addresses listed in the Remote Side Host/Network column. In detail mode (see the Show Detail button), an address column might contain an interface name with the word any, such as inside:any. any means that any host on the inside interface is affected by the rule.

Destination—Lists the IP addresses that are subject to this rule when traffic is sent from the IP addresses listed in the Security Appliance Side Host/Network column. In detail mode (see the

Show Detail button), an address column might contain an interface name with the word any, such as outside:any. any means that any host on the outside interface is affected by the rule. Also in detail mode, an address column might contain IP addresses in square brackets, for example,

[209.165.201.1-209.165.201.30]. These addresses are translated addresses. When an inside host makes a connection to an outside host, the adaptive security appliance maps the inside host's address to an address from the pool. After a host creates an outbound connection, the adaptive security appliance maintains this address mapping. This address mapping structure is called an xlate, and remains in memory for a period of time.

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•

•

•

•

•

•

•

•

•

•

•

–

Service—Specifies the service and protocol specified by the rule (TCP, UDP, ICMP, or IP).

–

Action—Specifies the type of IPsec rule (protect or do not protect).

Transform Set—Displays the transform set for the rule.

Peer—Identifies the IPsec peer.

PFS—Displays perfect forward secrecy settings for the rule.

NAT-T Enabled—Indicates whether NAT Traversal is enabled for the policy.

Reverse Route Enabled—Indicates whether Reverse Route Injection is enabled for the policy.

Connection Type—(Meaningful only for static tunnel policies.) Identifies the connection type for this policy as bidirectional, originate-only, or answer-only).

SA Lifetime—Displays the SA lifetime for the rule.

CA Certificate—Displays the CA certificate for the policy. This applies to static connections only.

IKE Negotiation Mode—Displays whether IKE negotiations use main or aggressive mode.

Description—(Optional) Specifies a brief description for this rule. For an existing rule, this is the description you typed when you added the rule. An implicit rule includes the following description:

“Implicit rule.” To edit the description of any but an implicit rule, right-click this column, and choose Edit Description or double-click the column.

Enable Anti-replay window size—Sets the anti-replay window size, between 64 and 1028 in multiples of 64. One side-effect of priority queueing in a hierarchical QoS policy with traffic shaping (see the “Rule Actions > QoS Tab” ) is packet re-ordering. For IPsec packets, out-of-order packets that are not within the anti-replay window generate warning syslog messages. These warnings becomes false alarms in the case of priority queueing. Configuring the anti-replay pane size helps you avoid possible false alarms.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Creating an IPsec Rule/Tunnel Policy (Crypto Map) - Basic Tab

Use this pane to define a new Tunnel Policy for an IPsec rule. The values you define here appear in the

IPsec Rules table after you click OK. All rules are enabled by default as soon as they appear in the IPsec

Rules table.

The Tunnel Policy pane lets you define a tunnel policy that is used to negotiate an IPsec (Phase 2) security association (SA). ASDM captures your configuration edits, but does not save them to the running configuration until you click Apply.

Every tunnel policy must specify a transform set and identify the security appliance interface to which it applies. The transform set identifies the encryption and hash algorithms that perform IPsec encryption and decryption operations. Because not every IPsec peer supports the same algorithms, you might want to specify a number of policies and assign a priority to each. The security appliance then negotiates with the remote IPsec peer to agree on a transform set that both peers support.

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Tunnel policies can be

static

or

dynamic

. A static tunnel policy identifies one or more remote IPsec peers or subnetworks to which your security appliance permits IPsec connections. A static policy can be used whether your security appliance initiates the connection or receives a connection request from a remote host. A static policy requires you to enter the information necessary to identify permitted hosts or networks.

A dynamic tunnel policy is used when you cannot or do not want to provide information about remote hosts that are permitted to initiate a connection with the security appliance. If you are only using your security appliance as a VPN client in relation to a remote VPN central-site device, you do not need to configure any dynamic tunnel policies. Dynamic tunnel policies are most useful for allowing remote access clients to initiate a connection to your network through a security appliance acting as the VPN central-site device. A dynamic tunnel policy is useful when the remote access clients have dynamically assigned IP addresses or when you do not want to configure separate policies for a large number of remote access clients.

Fields

•

Interface—Choose the interface name to which this policy applies.

•

Policy Type—Choose the type, static or dynamic, of this tunnel policy.

•

•

•

Priority—Enter the priority of the policy.

Transform Set to Be Added—Choose the transform set for the policy and click Add to move it to the list of active transform sets. Click Move Up or Move Down to rearrange the order of the transform sets in the list box. You can add a maximum of 11 transform sets to a crypto map entry or a dynamic crypto map entry.

Peer Settings - Optional for Dynamic Crypto Map Entries—Configure the peer settings for the policy.

–

Connection Type—(Meaningful only for static tunnel policies.) Choose bidirectional, originate-only, or answer-only to specify the connection type of this policy. For LAN-to-LAN connections, choose bidirectional or answer-only (not originate-only). Choose answer-only for

LAN-to-LAN redundancy.

•

•

–

IP Address of Peer to Be Added—Enter the IP address of the IPsec peer you are adding.

Enable Perfect Forwarding Secrecy—Check to enable perfect forward secrecy for the policy. PFS is a cryptographic concept where each new key is unrelated to any previous key. In IPsec negotiations,

Phase 2 keys are based on Phase 1 keys unless you specify Perfect Forward Secrecy.

Diffie-Hellman Group—When you enable PFS you must also choose a Diffie-Hellman group which the adaptive security appliance uses to generate session keys. The choices are as follows:

–

Group 1 (768-bits) = Use perfect forward secrecy, and use Diffie-Hellman Group 1 to generate

IPsec session keys, where the prime and generator numbers are 768 bits. This option is more secure but requires more processing overhead.

–

–


IPsec session keys, where the prime and generator numbers are 1024 bits. This option is more secure than Group 1 but requires more processing overhead.


IPsec session keys, where the prime and generator numbers are 1536 bits. This option is more secure than Group 2 but requires more processing overhead.

Modes


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Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Creating IPsec Rule/Tunnel Policy (Crypto Map) - Advanced Tab

Fields

•

Security Association Lifetime parameters—Configures the duration of a Security Association (SA).

This parameter specifies how to measure the lifetime of the IPsec SA keys, which is how long the

IPsec SA lasts until it expires and must be renegotiated with new keys.

–

–

Time—Specifies the SA lifetime in terms of hours (hh), minutes (mm) and seconds (ss).

Traffic Volume—Defines the SA lifetime in terms of kilobytes of traffic. Enter the number of kilobytes of payload data after which the IPsec SA expires. Minimum is 100 KB, default is

10000 KB, maximum is 2147483647 KB.

•

•

•

Enable NAT-T— Enables NAT Traversal (NAT-T) for this policy.

Enable Reverse Route Injection—Enables Reverse Route Injection for this policy.

Reverse Route Injection (RRI) is used to populate the routing table of an internal router that runs dynanmic routing protocols such as Open Shortest Path First (OSPF), or Enhanced Interior Gateway

Routing Protocol (EIGRP) , if you run ASA 8.0, or Routing Information Protocol (RIP) for remote

VPN Clients or LAN²LAN sessions.

Static Type Only Settings—Specifies parameters for static tunnel policies.

–

CA Certificate—Choose the certificate to use. If you choose something other than None (Use

Preshared Keys), which is the default, the Enable entire chain transmission check box becomes active.

–

–

Enable entire chain transmission—Enables transmission of the entire trust point chain.

IKE Negotiation Mode—Chooses the IKE negotiation mode, Main or Aggressive. This parameter sets the mode for exchanging key information and setting up the SAs. It sets the mode that the initiator of the negotiation uses; the responder auto-negotiates. Aggressive Mode is faster, using fewer packets and fewer exchanges, but it does not protect the identity of the communicating parties. Main Mode is slower, using more packets and more exchanges, but it protects the identities of the communicating parties. This mode is more secure and it is the default selection. If you choose Aggressive, the Diffie-Hellman Group list becomes active.

–

Diffie-Hellman Group—Choose the Diffie-Hellman group to apply. The choices are as follows:

Group 1 (768-bits), Group 2 (1024-bits), or Group 5 (1536-bits).

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

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Creating IPsec Rule/Traffic Selection Tab

This pane lets you define what traffic to protect (permit) or not protect (deny).

Fields

•

Action—Specify the action for this rule to take. The selections are protect and do not protect.

•

Source—Specify the IP address, network object group or interface IP address for the source host or network. A rule cannot use the same address as both the source and destination. Click ... to launch the Browse Source dialog box that contains the following fields:

–

Add/Edit—Choose IP Address or Network Object Group to add more source addresses or groups.

–

–

Delete—Click to delete an entry.

Filter—Enter an IP Address to filter the results displayed.

•

–

–

Name—Indicates that the parameters that follow specify the name of the source host or network.

IP Address—Indicates that the parameters that follow specify the interface, IP address, and subnet mask of the source host or network.

–

–

Netmask—Chooses a standard subnet mask to apply to the IP address. This parameter appears when you choose the IP Address option button.

Description—Enter a description.

–

Selected Source—Click

Source

to include the selected entry as a source.

Destination—Specify the IP address, network object group or interface IP address for the destination host or network. A rule cannot use the same address as both the source and destination.

Click ... to launch the Browse Destination dialog box that contains the following fields:

•

•

•

–

–

Add/Edit—Choose IP Address or Network Object Group to add more destination addresses or groups.

Delete—Click to delete an entry.

–

–

Filter—Enter an IP Address to filter the results displayed.

Name—Indicates that the parameters that follow specify the name of the destination host or network.

–

–

IP Address—Indicates that the parameters that follow specify the interface, IP address, and subnet mask of the destination host or network.

Netmask—Chooses a standard subnet mask to apply to the IP address. This parameter appears when you choose the IP Address option button.

–

–

Description—Enter a description.

Selected Destination—Click

Destination

to include the selected entry as a destination.

Service—Enter a service or click ... to launch the browse service dialog box where you can choose from a list of services.

Description—Enter a description for the Traffic Selection entry.

More Options

–

Enable Rule—Click to enable this rule.

–

–

Source Service—Enter a service or click

...

to launch the browse service dialog box where you can choose from a list of services.

Time Range—Define a time range for which this rule applies.


63-14 OL-20339-01



•

–

–

–

Group—Indicates that the parameters that follow specify the interface and group name of the source host or network.

Interface—Choose the interface name for the IP address. This parameter appears when you choose the IP Address option button.

IP address—Specifies the IP address of the interface to which this policy applies. This parameter appears when you choose the IP Address option button.

–

–

–

–

Destination—Specify the IP address, network object group or interface IP address for the source or destination host or network. A rule cannot use the same address as both the source and destination. Click ... for either of these fields to launch the Browse dialog box that contain the following fields:

Name—Choose the interface name to use as the source or destination host or network. This parameter appears when you choose the Name option button. This is the only parameter associated with this option.

Interface—Choose the interface name for the IP address. This parameter appears when you choose the Group option button.

Group—Choose the name of the group on the specified interface for the source or destination host or network. If the list contains no entries, you can enter the name of an existing group. This parameter appears when you choose the Group option button.

Protocol and Service

—Specifies protocol and service parameters relevant to this rule.

Note

“Any - any” IPsec rules are not allowed. This type of rule would prevent the device and its peer from supporting multiple LAN -to-LAN tunnels.

–

–

–

–

–

–

–

–

–

–

TCP

—Specifies that this rule applies to TCP connections. This selection also displays the

Source Port

and

Destination Port

group boxes.

UDP

—Specifies that this rule applies to UDP connections. This selection also displays the

Source Port

and


group boxes.

ICMP

—Specifies that this rule applies to ICMP connections. This selection also displays the

ICMP Type

group box.

IP

—Specifies that this rule applies to IP connections. This selection also displays the

IP

Protocol

group box.

Manage Service Groups

—Displays the Manage Service Groups pane, on which you can add, edit, or delete a group of TCP/UDP services/ports.

Source Port

and


—Contains TCP or UDP port parameters, depending on which option button you chose in the Protocol and Service group box.

Service

—Indicates that you are specifying parameters for an individual service. Specifies the name of the service and a boolean operator to use when applying the filter.

Boolean operator

(unlabeled)—Lists the boolean conditions (equal, not equal, greater than, less than, or range) to use in matching the service specified in the service box.

Service

(unlabeled)—Identifies the service (such as https, kerberos, or any) to be matched. If you specified the range service operator this parameter becomes two boxes, into which you enter the start and the end of the range.

...

—Displays a list of services from which you can choose the service to display in the Service box.

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•

–

Service Group

—Indicates that you are specifying the name of a service group for the source port.

–

–

Service

(unlabeled)—Choose the service group to use.

ICMP Type

—Specifies the ICMP type to use. The default is any. Click the

...

button to display a list of available types.

Options

–

Time Range

—Specify the name of an existing time range or create a new range.

–

–

...

—Displays the Add Time Range pane, on which you can define a new time range.

Please enter the description below (optional)

—Provides space for you to enter a brief description of the rule.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Pre-Fragmentation

Use this pane to set the IPsec pre-fragmentation policy and do-not-fragment (DF) bit policy for any interface.

The IPsec pre-fragmentation policy specifies how to treat packets that exceed the maximum transmission unit (MTU) setting when tunneling traffic through the public interface. This feature provides a way to handle cases where a router or NAT device between the adaptive security appliance and the client rejects or drops IP fragments. For example, suppose a client wants to FTP get from an FTP server behind a adaptive security appliance. The FTP server transmits packets that when encapsulated would exceed the adaptive security appliance’s MTU size on the public interface. The selected options determine how the adaptive security appliance processes these packets. The pre-fragmentation policy applies to all traffic travelling out the adaptive security appliance public interface.

The adaptive security appliance encapsulates all tunneled packets. After encapsulation, the adaptive security appliance fragments packets that exceed the MTU setting before transmitting them through the public interface. This is the default policy. This option works for situations where fragmented packets are allowed through the tunnel without hindrance. For the FTP example, large packets are encapsulated and then fragmented at the IP layer. Intermediate devices may drop fragments or just out-of-order fragments. Load-balancing devices can introduce out-of-order fragments.

When you enable pre-fragmentation, the adaptive security appliance fragments tunneled packets that exceed the MTU setting before encapsulating them. If the DF bit on these packets is set, the adaptive security appliance clears the DF bit, fragments the packets, and then encapsulates them. This action creates two independent non-fragmented IP packets leaving the public interface and successfully transmits these packets to the peer site by turning the fragments into complete packets to be reassembled at the peer site. In our example, the adaptive security appliance overrides the MTU and allows fragmentation by clearing the DF bit.

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Note

Changing the MTU or the pre-fragmentation option on

any

interface tears down

all

existing connections.

For example, if 100 active tunnels terminate on the public interface, and you change the MTU or the pre-fragmentation option on the external interface, all of the active tunnels on the public interface are dropped.

Fields

• Pre-Fragmentation

—Shows the current pre-fragmentation configuration for every configured interface.

–

Interface

—Shows the name of each configured interface.

•

–

–

Pre-Fragmentation Enabled

—Shows, for each interface, whether pre-fragmentation is enabled.

DF Bit Policy

—Shows the DF Bit Policy for each interface.

Edit

—Displays the Edit IPsec Pre-Fragmentation Policy dialog box.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Edit IPsec Pre-Fragmentation Policy

Use this pane to modify an existing IPsec pre-fragmentation policy and do-not-fragment (DF) bit policy for an interface selected on the parent pane,

Configuration > VPN > IPsec > Pre-Fragmentation

Fields

•

Interface

—Identifies the chosen interface. You cannot change this parameter using this dialog box.

•

•

Enable IPsec pre-fragmentation

—Enables or disables IPsec pre-fragmentation. The adaptive security appliance fragments tunneled packets that exceed the MTU setting before encapsulating them. If the DF bit on these packets is set, the adaptive security appliance clears the DF bit, fragments the packets, and then encapsulates them. This action creates two independent, non-fragmented IP packets leaving the public interface and successfully transmits these packets to the peer site by turning the fragments into complete packets to be reassembled at the peer site.

DF Bit Setting Policy

—Choose the do-not-fragment bit policy: Copy, Clear, or Set.

Modes


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Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

IPsec Transform Sets

Use this pane to view and add or edit transform sets. A transform is a set of operations done on a data flow to provide data authentication, data confidentiality, and data compression. For example, one transform is the ESP protocol with 3DES encryption and the HMAC-MD5 authentication algorithm

(ESP-3DES-MD5).

•

•

•

Fields

•

Transform Sets

—Shows the configured transform sets.

–

–

Name

—Shows the name of the transform sets.

Mode

—Shows the mode, Tunnel, of the transform set. This parameter specifies the mode for applying ESP encryption and authentication; in other words, what part of the original IP packet has ESP applied. Tunnel mode applies ESP encryption and authentication to the entire original

IP packet (IP header and data), thus hiding the ultimate source and destination addresses.

–

–

ESP Encryption

—Shows the Encapsulating Security Protocol (ESP) encryption algorithms for the transform sets. ESP provides data privacy services, optional data authentication, and anti-replay services. ESP

encapsulates

the data being protected.

ESP Authentication

—Shows the ESP authentication algorithms for the transform sets.

Add

—Opens the Add Transform Set dialog box, in which you can add a new transform set.

Edit

—Opens the Edit Transform Set dialog box, in which you can modify an existing transform set.

Delete

—Removes the selected transform set. There is no confirmation or undo.

Modes


Firewall Mode

Routed

•



—

•

Multiple

Context

—

System

—

Add/Edit Transform Set

Use this pane to add or modify a transform set. A transform is a set of operations done on a data flow to provide data authentication, data confidentiality, and data compression. For example, one transform is the ESP protocol with 3DES encryption and the HMAC-MD5 authentication algorithm

(ESP-3DES-MD5).

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Configuring Load Balancing

Fields

•

Set Name

—Specifies a name for this transform set.

•

Properties

—Configures properties for this transform set. These properties appear in the Transform

Sets table.

–

–

–

Mode

—Shows the mode, Tunnel, of the transform set. This field shows the mode for applying

ESP encryption and authentication; in other words, what part of the original IP packet has ESP applied. Tunnel mode applies ESP encryption and authentication to the entire original IP packet

(IP header and data), thus hiding the ultimate source and destination addresses.

ESP Encryption

—Choose the Encapsulating Security Protocol (ESP) encryption algorithms for the transform sets. ESP provides data privacy services, optional data authentication, and anti-replay services. ESP

encapsulates

the data being protected.

ESP Authentication

—Choose the ESP authentication algorithms for the transform sets.

Note

The IPsec ESP (Encapsulating Security Payload) protocol provides both encryption and authentication. Packet authentication proves that data comes from whom you think it comes from; it is often referred to as “data integrity.”

Modes


14-32

Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—


If you have a remote-client configuration in which you are using two or more adaptive security appliances connected to the same network to handle remote sessions, you can configure these devices to share their session load. This feature is called

load balancing

. Load balancing directs session traffic to the least loaded device, thus distributing the load among all devices. It makes efficient use of system resources and provides increased performance anodize availability.

Note

To use VPN load balancing, you must have an ASA Model 5510 with a Plus license or an ASA Model

5520 or higher. VPN load balancing also requires an active 3DES/AES license. The security appliance checks for the existence of this crypto license before enabling load balancing. If it does not detect an active 3DES or AES license, the security appliance prevents the enabling of load balancing and also prevents internal configuration of 3DES by the load balancing system unless the license permits this usage.

The following sections explain load balancing:

•

Eligible Clients

•

Enabling Load Balancing

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•

•

•

•

Creating Virtual Clusters

Mixed Cluster Scenarios

Comparing Load Balancing to Failover

Load Balancing Prerequisites

Eligible Clients

Load balancing is effective only on remote sessions initiated with the following clients:

•

•

•

•

•

•

Cisco AnyConnect VPN Client (Release 2.0 and later)

Cisco VPN Client (Release 3.0 and later)

Cisco ASA 5505 Security Appliance (when acting as an Easy VPN client)

Cisco VPN 3002 Hardware Client (Release 3.5 or later)

Cisco PIX 501/506E when acting as an Easy VPN client

IOS EZVPN Client devices supporting IKE-redirect (IOS 831/871)

•

Clientless SSL VPN (not a client)

Load balancing works with IPsec clients and SSL VPN client and clientless sessions. All other VPN connection types (L2TP, PPTP, L2TP/IPsec), including LAN-to-LAN, can connect to an adaptive security appliance on which load balancing is enabled, but they cannot participate in load balancing.

Enabling Load Balancing

This pane lets you enable load balancing on the adaptive security appliance. Enabling load balancing involves:

•

Configuring the load-balancing cluster by establishing a common virtual cluster IP address, UDP port (if necessary), and IPsec shared secret for the cluster. These values are identical for every device in the cluster.

•

Configuring the participating device by enabling load balancing on the device and defining device-specific properties. These values vary from device to device.

Creating Virtual Clusters

To implement load balancing, you group together logically two or more devices on the same private

LAN-to-LAN network into a

virtual cluster

.

All devices in the virtual cluster carry session loads. One device in the virtual cluster, the

virtual cluster master

, directs incoming calls to the other devices, called

backup devices

. The virtual cluster master monitors all devices in the cluster, keeps track of how busy each is, and distributes the session load accordingly. The role of virtual cluster master is not tied to a physical device; it can shift among devices.

For example, if the current virtual cluster master fails, one of the backup devices in the cluster takes over that role and immediately becomes the new virtual cluster master.

The virtual cluster appears to outside clients as a single

virtual cluster IP address

. This IP address is not tied to a specific physical device. It belongs to the current virtual cluster master; hence, it is virtual. A

VPN client attempting to establish a connection connects first to this virtual cluster IP address. The

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virtual cluster master then sends back to the client the public IP address of the least-loaded available host in the cluster. In a second transaction (transparent to the user) the client connects directly to that host.

In this way, the virtual cluster master directs traffic evenly and efficiently across resources.

Note

All clients other than the Cisco VPN client, the Cisco VPN 3002 Hardware Client, or the ASA 5505 operating as an Easy VPN Client connect directly to the adaptive security appliance as usual; they do not use the virtual cluster IP address.

If a machine in the cluster fails, the terminated sessions can immediately reconnect to the virtual cluster

IP address. The virtual cluster master then directs these connections to another active device in the cluster. Should the virtual cluster master itself fail, a backup device in the cluster immediately and automatically takes over as the new virtual session master. Even if several devices in the cluster fail, users can continue to connect to the cluster as long as any one device in the cluster is up and available

A load-balancing cluster can consist of adaptive security appliances of the same release, of mixed releases, as well as VPN 3000 concentrators, or a mixture of these, subject to the following restrictions:

•

Load-balancing clusters that consist of both same release adaptive security appliances and VPN

3000 concentrators can run load balancing for a mixture of IPsec, AnyConnect, and clientless SSL

VPN client and clientless sessions.

•

Load-balancing clusters that include mixed release adaptive security appliances or same release adaptive security appliances and VPN 3000 concentrators or both can support only IPsec sessions.

In such a configuration, however, the adaptive security appliances might not reach their full IPsec capacity.

“Scenario 1: Mixed Cluster with No SSL VPN Connections” on page 22

, illustrates this situation.

Since Release 7.1(1), IPsec and SSL VPN sessions count or weigh equally in determining the load that each device in the cluster carries. This represents a departure from the load balancing calculation for the

ASA Release 7.0(x) software and the VPN 3000 concentrator, in that these platforms both use a weighting algorithm that, on some hardware platforms, calculates SSL VPN session load differently from IPsec session load.

The virtual master of the cluster assigns session requests to the members of the cluster. The adaptive security appliance regards all sessions, SSL VPN or IPsec, as equal and assigns them accordingly. You can configure the number of IPsec and SSL VPN sessions to allow, up to the maximum allowed by your configuration and license.

We have tested up to ten nodes in a load-balancing cluster. Larger clusters might work, but we do not officially support such topologies.

Mixed Cluster Scenarios

If you have a mixed configuration—that is, if your load-balancing cluster includes devices running a mixture of ASA software releases or at least one adaptive security appliance running ASA Release 7.1(1) or later and a VPN 3000 concentrator—the difference in weighting algorithms becomes an issue if the initial cluster master fails and another device takes over as master.

The following scenarios illustrate the use of VPN load balancing in clusters consisting of a mixture of adaptive security appliances running ASA Release 7.1(1) and ASA Release 7.0(x) software, as well as

VPN 3000 Series Concentrators.

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Scenario 1: Mixed Cluster with No SSL VPN Connections

In this scenario, the cluster consists of a mixture of adaptive security appliances and VPN 3000

Concentrators. Some of the adaptive security appliance cluster peers are running ASA Release 7.0(x), and some are running Release 7.1(1). The pre-7.1(1) and VPN 3000 peers do not have any SSL VPN connections, and the 7.1(1) cluster peers have only the base SSL VPN license, which allows two SSL

VPN sessions, but there are no SSL VPN connections. In this case, all the connections are IPsec, and load balancing works fine.

The two SSL VPN licenses have a very small effect on the user’s taking advantage of the maximum IPsec session limit, and then only when a VPN 3000 Concentrator is the cluster master. In general, the smaller the number of SSL VPN licenses is on a adaptive security appliance in a mixed cluster, the smaller the effect on the ASA 7.1(1) device being able to reach its IPsec session limit in a scenario where there are only IPsec sessions.

Scenario 2: Mixed Cluster Handling SSL VPN Connections

Suppose, for example, a adaptive security appliance running ASA Release 7.1(1) software is the initial cluster master; then that device fails. Another device in the cluster takes over automatically as master and applies its own load-balancing algorithm to determine processor loads within the cluster. A cluster master running ASA Release 7.1(1) software cannot weight session loads in any way other than what that software provides. Therefore, it cannot assign a combination of IPsec and SSL VPN session loads properly to ASA devices running earlier versions nor to VPN 3000 Concentrators. Conversely, a VPN

3000 Concentrator acting as the cluster master cannot assign loads properly to an ASA Release 7.1(1) adaptive security appliance. The following scenario illustrates this dilemma.

This scenario is similar to the previous one, in that the cluster consists of a mixture of adaptive security appliances and VPN 3000 Concentrators. Some of the adaptive security appliance cluster peers are running ASA Release 7.0,(x) and some are running Release 7.1(1). In this case, however, the cluster is handling SSL VPN connections as well as IPsec connections.

If a device that is running software earlier than ASA Release 7.1(1) is the cluster master, the master applies the protocol and logic in effect prior to Release 7.1(1). That is, sessions might be directed to load-balancing peers that have exceeded their session limit. In that case, the user is denied access.

If the cluster master is a device running ASA Release 7.0(x) software, the old session-weighting algorithm applies only to the pre-7.1(1) peers in the cluster. No one should be denied access in this case.

Because the pre-7.1(1) peers use the session-weighting algorithm, they are more lightly loaded.

An issue arises, however, because you cannot guarantee that the 7.1(1) peer is always the cluster master.

If the cluster master fails, another peer assumes the role of master. The new master might be any of the eligible peers. Because of the innately unpredictability of the results, we recommend that you avoid configuring this type of cluster.

Comparing Load Balancing to Failover

Both load balancing and failover are high-availability features, but they function differently and have different requirements. In some circumstances you can use both load balancing and failover. The following sections describe the differences between these features.

Load balancing

is a mechanism for equitably distributing remote-access VPN traffic among the devices in a virtual cluster. It is based on simple distribution of traffic without taking into account throughput or other factors. A load-balancing cluster consists of two or more devices, one of which is the virtual master, and the others backup. These devices do not need to be of the exact same type, or have identical software versions or configurations. All active devices in a virtual cluster carry session loads. Load balancing directs traffic to the least loaded device in the cluster, distributing the load among all devices.

It makes efficient use of system resources and provides increased performance and high availability.


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A

failover

configuration requires two identical adaptive security appliances connected to each other through a dedicated failover link and, optionally, a stateful failover link. The health of the active interfaces and units is monitored to determine when specific failover conditions are met. If those conditions occur, failover occurs. Failover supports both VPN and firewall configurations.

The adaptive security appliance supports two failover configurations, Active/Active failover and

Active/Standby failover. VPN connections run only in Active/Standby, single routed mode.

Active/Active failover requires multi-context mode, so does not support VPN connections.

With Active/Active failover, both units can pass network traffic. This is not true load balancing, although it might appear to have the same effect. When failover occurs, the remaining active unit takes over passing the combined traffic, based on he configured parameters. Therefore, when configuring

Active/Active failover, you must make sure that the combined traffic for both units is within the capacity of each unit.

With Active/Standby failover, only one unit passes traffic, while the other unit waits in a standby state and does not pass traffic. Active/Standby failover lets you use a second adaptive security applianceto take over the functions of a failed unit. When the active unit fails, it changes to the standby state, while the standby unit changes to the active state. The unit that becomes active assumes the IP addresses (or, for transparent firewall, the management IP address) and MAC addresses of the failed unit and begins passing traffic. The unit that is now in standby state takes over the standby IP addresses of the active unit. If an active unit fails, the standby takes over without any interruption to the client VPN tunnel.

Load Balancing Prerequisites

Load balancing is disabled by default. You must explicitly enable load balancing.

You must have first configured the public and private interfaces and also have previously configured the the interface to which the virtual cluster IP address refers.

All devices that participate in a cluster must share the same cluster-specific values: IP address, encryption settings, encryption key, and port. All of the outside and inside network interfaces on the load-balancing devices in a cluster must be on the same IP network.

Fields

•

VPN Load Balancing

—Configures virtual cluster device parameters.

–

–

Participate in Load Balancing Cluster

—Specifies that this device is a participant in the load-balancing cluster.

VPN Cluster Configuration

—Configures device parameters that must be the same for the entire virtual cluster. All servers in the cluster must have an identical cluster configuration.

–

–

–

Cluster IP Address

—Specifies the single IP address that represents the entire virtual cluster.

Choose an IP address that is within the public subnet address range shared by all the adaptive security appliances in the virtual cluster.

UDP Port

—Specifies the UDP port for the virtual cluster in which this device is participating.

The default value is 9023. If another application is using this port, enter the UDP destination port number you want to use for load balancing.

Enable IPsec Encryption

—Enables or disables IPsec encryption. If you check this box, you must also specify and verify a shared secret.The adaptive security appliances in the virtual cluster communicate via LAN-to-LAN tunnels using IPsec. To ensure that all load-balancing information communicated between the devices is encrypted, check this box.

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Note

When using encryption, you must have previously configured the load-balancing inside interface. If that interface is not enabled on the load-balancing inside interface, you get an error message when you try to configure cluster encryption.

If the load-balancing inside interface was enabled when you configured cluster encryption, but was disabled before you configured the participation of the device in the virtual cluster, you get an error message when you check the Participate in Load Balancing Cluster check box, and encryption is not enabled for the cluster.

•

–

IPsec Shared Secret

—Specifies the shared secret to between IPsec peers when you have enabled IPsec encryption. The value you enter in the box appears as consecutive asterisk characters.

–

Verify Secret

—Confirms the shared secret value entered in the IPsec Shared Secret box.

VPN Server Configuration

—Configures parameters for this specific device.

–

Interfaces

—Configures the public and private interfaces and their relevant parameters.

–

–

–

Public

—Specifies the name or IP address of the public interface for this device.

Private

—Specifies the name or IP address of the private interface for this device.

Priority

—Specifies the priority assigned to this device within the cluster. The range is from 1 to 10. The priority indicates the likelihood of this device becoming the virtual cluster master, either at start-up or when an existing master fails. The higher you set the priority (for example,

10), the more likely this device becomes the virtual cluster master.

Note

If the devices in the virtual cluster are powered up at different times, the first device to be powered up assumes the role of virtual cluster master. Because every virtual cluster requires a master, each device in the virtual cluster checks when it is powered-up to ensure that the cluster has a virtual master. If none exists, that device takes on the role. Devices powered up and added to the cluster later become backup devices. If all the devices in the virtual cluster are powered up simultaneously, the device with the highest priority setting becomes the virtual cluster master.

If two or more devices in the virtual cluster are powered up simultaneously, and both have the highest priority setting, the one with the lowest IP address becomes the virtual cluster master.

–

NAT Assigned IP Address

—Specifies the IP address that this device’s IP address is translated to by NAT. If NAT is not being used (or if the device is not behind a firewall using NAT), leave the field blank.

–

Send FQDN to client

—Check this check box to cause the VPN cluster master to send a fully qualified domain name using the host and domain name of the cluster device instead of the outside IP address when redirecting VPN client connections to that cluster device.

By default, the ASA sends only IP addresses in load-balancing redirection to a client. If certificates are in use that are based on DNS names, the certificates will be invalid when redirected to a backup device.

As a VPN cluster master, this adaptive security appliance can send a fully qualified domain name (FQDN), using reverse DNS lookup, of a cluster device (another adaptive security appliance in the cluster), instead of its outside IP address, when redirecting VPN client connections to that cluster device.

All of the outside and inside network interfaces on the load-balancing devices in a cluster must be on the same IP network.

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Setting Global NAC Parameters

To enable Clientless SSL VPN load balancing using FQDNs rather than IP addresses, perform the following configuration steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Enable the use of FQDNs for Load Balancing by checking the Send FQDN to client... checkbox.

Add an entry for each of your adaptive security appliance outside interfaces into your DNS server, if such entries are not already present. Each adaptive security appliance outside IP address should have a

DNS entry associated with it for lookups. These DNS entries must also be enabled for Reverse Lookup.

Enable DNS lookups on your adaptive security appliance on the dialog box Configuration > Device

Management > DNS > DNS Client for whichever interface has a route to your DNS server.

Define your DNS server IP address on the adaptive security appliance. To do this, click Add on this dialog box. This opens the Add DNS Server Group dialog box. Enter the IP address of the DNS server you want to add; for example,

192.168.1.1

(IP address of your DNS server).

Click OK and Apply.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Setting Global NAC Parameters

The adaptive security appliance uses Extensible Authentication Protocol (EAP) over UDP (EAPoUDP) messaging to validate the posture of remote hosts. Posture validation involves checking a remote host for compliancy with safety requirements before the assignment of a network access policy. An Access

Control Server must be configured for Network Admission Control before you configure NAC on the adaptive security appliance.

Fields

The NAC pane lets you set attributes that apply to all NAC communications. The following global attributes at the top of the pane apply to EAPoUDP messaging between the adaptive security appliance and remote hosts:

•

Port—Port number for EAP over UDP communication with the Cisco Trust Agent (CTA) on the host. This number must match the port number configured on the CTA. Enter a value in the range

1024 to 65535. The default setting is 21862.

•

Retry if no response—Number of times the adaptive security appliance resends an EAP over UDP message. This attribute limits the number of consecutive retries sent in response to Rechallenge

Interval expirations. The setting is in seconds. Enter a value in the range 1 to 3. The default setting is 3.

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Configuring Network Admission Control Policies

•

•

Wait before new PV Session—The adaptive security appliance starts this timer when it places the

NAC session for a remote host into a hold state. It places a session in a hold state if it does not receive a response after sending EAPoUDP messages equal to the value of the “Retry if no response” setting. The adaptive security appliance also starts this timer after it receives an Access Reject message from the ACS server. When the timer expires, the adaptive security appliance tries to initiate a new EAP over UDP association with the remote host. The setting is in seconds. Enter a value in the range 60 to 86400. The default setting is 180.

The Clientless Authentication area of the NAC pane lets you configure settings for hosts that are not responsive to the EAPoUDP requests. Hosts for which there is no CTA running do not respond to these requests.

•

Rechallenge Interval—The adaptive security appliance starts this timer when it sends an EAPoUDP message to the host. A response from the host clears the timer. If the timer expires before the adaptive security appliance receives a response, it resends the message. The setting is in seconds.

Enter a value in the range 1 to 60. The default setting is 3.

•

•

•

•

Enable clientless authentication—Click to enable clientless authentication. The adaptive security appliance sends the configured clientless username and password to the Access Control Server in the form of a user authentication request. The ACS in turn requests the access policy for clientless hosts. If you leave this attribute blank, the adaptive security appliance applies the default ACL for clientless hosts.

Clientless Username—Username configured for clientless hosts on the ACS. The default setting is clientless. Enter 1 to 64 ASCII characters, excluding leading and trailing spaces, pound signs (#), question marks (?), single and double quotation marks (“ ” and "), asterisks (*), and angle brackets

(< and >).

Password—Password configured for clientless hosts on the ACS. The default setting is clientless.

Enter 4 – 32 ASCII characters.

Confirm Password—Password configured for clientless hosts on the ACS repeated for validation.

•

Enable Audit—Click to pass the IP address of the client to an optional audit server if the client does not respond to a posture validation request. The audit server, such as a Trend server, uses the host

IP address to challenge the host directly to assess its health. For example, it may challenge the host to determine whether its virus checking software is active and up-to-date. After the audit server completes its interaction with the remote host, it passes a token to the posture validation server, indicating the health of the remote host.

None—Click to disable clientless authentication and audit services.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—


The NAC Policies table displays the Network Admission Control (NAC) policies configured on the adaptive security appliance.


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To add, change, or remove a NAC policy, do one of the following:

•

•

To add a NAC policy, choose

Add

. The Add NAC Framework Policy dialog box opens.

To change a NAC policy, double-click it, or select it and click

Edit

. The Edit NAC Framework Policy dialog box opens.

•

To remove a NAC policy, select it and click

Delete

.

The following sections describe NAC, its requirements, and how to assign values to the policy attributes:

•

•

•

•

About NAC

Uses, Requirements, and Limitations

Fields

What to Do Next

About NAC

NAC protects the enterprise network from intrusion and infection from worms, viruses, and rogue applications by performing endpoint compliance and vulnerability checks as a condition for production access to the network. We refer to these checks as

posture validation.

You can configure posture validation to ensure that the anti-virus files, personal firewall rules, or intrusion protection software on a host with an AnyConnect or Clientless SSL VPN session are up-to-date before providing access to vulnerable hosts on the intranet. Posture validation can include the verification that the applications running on the remote hosts are updated with the latest patches. NAC occurs only after user authentication and the setup of the tunnel. NAC is especially useful for protecting the enterprise network from hosts that are not subject to automatic network policy enforcement, such as home PCs.

The establishment of a tunnel between the endpoint and the adaptive security appliance triggers posture validation.

You can configure the adaptive security appliance to pass the IP address of the client to an optional audit server if the client does not respond to a posture validation request. The audit server, such as a Trend server, uses the host IP address to challenge the host directly to assess its health. For example, it may challenge the host to determine whether its virus checking software is active and up-to-date. After the audit server completes its interaction with the remote host, it passes a token to the posture validation server, indicating the health of the remote host.

Following successful posture validation or the reception of a token indicating the remote host is healthy, the posture validation server sends a network access policy to the adaptive security appliance for application to the traffic on the tunnel.

In a

NAC Framework

configuration involving the adaptive security appliance, only a Cisco Trust Agent running on the client can fulfill the role of posture agent, and only a Cisco Access Control Server (ACS) can fulfill the role of posture validation server. The ACS uses dynamic ACLs to determine the access policy for each client.

As a RADIUS server, the ACS can authenticate the login credentials required to establish a tunnel, in addition to fulfilling its role as posture validation server.

Note

Only a NAC Framework policy configured on the adaptive security appliance supports the use of an audit server.

In its role as posture validation server, the ACS uses access control lists. If posture validation succeeds and the ACS specifies a redirect URL as part of the access policy it sends to the adaptive security appliance, the adaptive security appliance redirects all HTTP and HTTPS requests from the remote host

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to the redirect URL. Once the posture validation server uploads an access policy to the adaptive security appliance, all of the associated traffic must pass both the Security Appliance and the ACS (or vice versa) to reach its destination.

The establishment of a tunnel between a remote host and the adaptive security appliance triggers posture validation if a NAC Framework policy is assigned to the group policy. The NAC Framework policy can, however, identify operating systems that are exempt from posture validation and specify an optional

ACL to filter such traffic.

Uses, Requirements, and Limitations

When configured to support NAC, the adaptive security appliance functions as a client of a Cisco Secure

Access Control Server, requiring that you install a minimum of one Access Control Server on the network to provide NAC authentication services.

Following the configuration of one or more Access Control Servers on the network, you must register the Access Control Server group, using the

Configuration > Remote Access VPN > Clientless SSL

VPN Access > Group Policies > Add or Edit External

menu option. Then add the NAC policy.

ASA support for NAC Framework is limited to remote access IPsec and Clientless SSL VPN sessions.

The NAC Framework configuration supports only single mode.

NAC on the ASA does not support Layer 3 (non-VPN) and IPv6 traffic.

Fields

•

Policy Name—Enter a string of up to 64 characters to name the new NAC policy.

Following the configuration of the NAC policy, the policy name appears next to the NAC Policy attribute in the Network (Client) Access group policies. Assign a name that will help you to distinguish its attributes or purpose from others that you may configure.

•

•

Status Query Period—The adaptive security appliance starts this timer after each successful posture validation and status query response. The expiration of this timer triggers a query for changes in the host posture, referred to as a

status query

. Enter the number of seconds in the range 30 to 1800. The default setting is 300.

Revalidation Period—The adaptive security appliance starts this timer after each successful posture validation. The expiration of this timer triggers the next unconditional posture validation. The adaptive security appliance maintains posture validation during revalidation. The default group policy becomes effective if the Access Control Server is unavailable during posture validation or revalidation. Enter the interval in seconds between each successful posture validation. The range is

300 to 86400. The default setting is 36000.

•

•

•

Default ACL— (Optional) The adaptive security appliance applies the security policy associated with the selected ACL if posture validation fails. Select None or select an extended ACL in the list.

The default setting is None. If the setting is None and posture validation fails, the adaptive security appliance applies the default group policy.

Use the Manage button to populate the drop-down list and view the configuration of the ACLs in the list.

Manage— Opens the ACL Manager dialog box. Click to view, enable, disable, and delete standard

ACLs and the ACEs in each ACL. The list next to the Default ACL attribute displays the ACLs.

Authentication Server Group—Specifies the authentication server group to use for posture validation. The drop-down list next to this attribute displays the names of all server groups of type

RADIUS configured on this adaptive security appliance that are available for remote access tunnels.

Select an ACS group consisting of at least one server configured to support NAC.

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•

•

•

•

Posture Validation Exception List—Displays one or more attributes that exempt remote computers from posture validation. At minimum, each entry lists the operating system and an Enabled setting of Yes or No. An optional filter identifies an ACL used to match additional attributes of the remote computer. An entry that consists of an operating system and a filter requires the remote computer to match both to be exempt from posture validation. The adaptive security appliance ignores the entry if the Enabled setting is set to No.

Add—Adds an entry to the Posture Validation Exception list.

Edit—Modifies an entry in the Posture Validation Exception list.

Delete—Removes an entry from the Posture Validation Exception list.

What to Do Next

Following the configuration of the NAC policy, you must assign it to a group policy for it to become active. To do so, choose

Configuration > Remote Access VPN> Network (Client) Access > Group

Policies > Add

or

Edit > General

>

More Options

and the NAC policy name from the drop-down list next to the NAC Policy attribute.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit Posture Validation Exception

The Add/Edit Posture Validation Exception dialog pane lets you exempt remote computers from posture validation, based on their operating system and other optional attributes that match a filter.

•

Operating System—Choose the operating system of the remote computer. If the computer is running this operating system, it is exempt from posture validation. The default setting is blank.

•

•

Enable—The adaptive security appliance checks the remote computer for the attribute settings displayed in this pane only if you check Enabled. Otherwise, it ignores the attribute settings. The default setting is unchecked.

Filter— (Optional) Use to apply an ACL to filter the traffic if the operating system of the computer matches the value of the Operating System attribute.

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•

Manage— Opens the ACL Manager dialog box. Click to view, enable, disable, and delete standard

ACLs and the ACEs in each ACL. The list next to the Default ACL attribute displays the ACLs. Use this button to populate the list next to the Filter attribute.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

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C H A P T E R

64

General VPN Setup

A virtual private network is a network of virtual circuits that carry private traffic over a public network such as the Internet. VPNs can connect two or more LANS, or remote users to a LAN. VPNs provide privacy and security by requiring all users to authenticate and by encrypting all data traffic.

•

Client Software, page 64-1

•

•

•

•

•

Default Tunnel Gateway, page 64-4

Group Policies, page 64-5

ACL Manager, page 64-15

Configuring AnyConnect (SSL) VPN Client Connections, page 64-39

•

•

•

•

Configuring SSL VPN Connections, page 64-48

Configuring AnyConnect Secure Mobility, page 64-60

IPsec Remote Access Connection Profiles, page 64-70

Add or Edit an IPsec Remote Access Connection Profile, page 64-71

•

•

•

•

•

Mapping Certificates to IPsec or SSL VPN Connection Profiles, page 64-72

System Options, page 64-101

Zone Labs Integrity Server, page 64-102

Easy VPN Remote, page 64-104

Advanced Easy VPN Properties, page 64-106

AnyConnect Essentials, page 64-108

Client Software

The Client Software pane lets administrators at a central location do the following actions:

•

•

•

Enable client update; specify the types and revision numbers of clients to which the update applies.

Provide a URL or IP address from which to get the update.

In the case of Windows clients, optionally notify users that they should update their VPN client version.


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Chapter 64 General VPN Setup

Client Software

Note

The Client Update function in Configuration > Remote Access VPN > Network (Client) Access >

Advanced > IPsec > Upload Software > Client Software applies only to the IPsec VPN client, (For

Windows, MAC OS X, and Linux), and the VPN 3002 hardware client. It does not apply to the Cisco

AnyConnect VPN clients, which is updated by the adaptive security appliance automatically when it connects.

For the IPsec VPN client, you can provide a mechanism for users to accomplish that update. For VPN

3002 hardware client users, the update occurs automatically, with no notification. You can apply client updates only to the IPsec remote-access tunnel-group type.

Note

If you try to do a client update to an IPsec Site-to-Site IPsec connection or a Clientless VPN IPsec connection, you do not receive an error message, but no update notification or client update goes to those types of IPsec connections.

To enable client update globally for all clients of a particular client type, use this dialog box. You can also notify all Windows, MAC OS X, and Linux clients that an upgrade is needed and initiate an upgrade on all VPN 3002 hardware clients from this dialog box. To configure the client revisions to which the update applies and the URL or IP address from which to download the update, click

Edit

.

To configure client update revisions and software update sources for a specific tunnel group, choose

Configuration > Remote Access VPN > Network (Client) Access > IPsec > Add/Edit > Advanced >

IPsec > Client Software Update

.

Fields

•

Enable Client Update—Enables or disables client update, both globally and for specific tunnel groups. You must enable client update before you can send a client update notification to Windows,

MAC OS X, and Linux VPN clients, or initiate an automatic update to hardware clients.

•

•

Client Type—Lists the clients to upgrade: software or hardware, and for Windows software clients, all Windows or a subset. If you click All Windows Based, do not specify Windows 95, 98 or ME and

Windows NT, 2000 or XP individually. The hardware client gets updated with a release of the ASA

5505 software or of the VPN 3002 hardware client.

VPN Client Revisions—Contains a comma-separated list of software image revisions appropriate for this client. If the user client revision number matches one of the specified revision numbers, there is no need to update the client, and, for Windows-based clients, the user does not receive an update notification. The following caveats apply:

–

–

The revision list must include the software version for this update.

Your entries must match exactly those on the URL for the VPN client, or the TFTP server for the hardware client.

•

–

–

The TFTP server for distributing the hardware client image must be a robust TFTP server.

A VPN client user must download an appropriate software version from the listed URL.

–

The VPN 3002 hardware client software is automatically updated via TFTP, with no notification to the user.

Image URL—Contains the URL or IP address from which to download the software image. This

URL must point to a file appropriate for this client. For Windows, MAC OS X, and Linux-based clients, the URL must be in the form: http:// or https://. For hardware clients, the URL must be in the form tftp://.

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Client Software

•

•

–

–

For Windows, MAC OS X, and Linux-based VPN clients: To activate the Launch button on the

VPN Client Notification, the URL must include the protocol HTTP or HTTPS and the server address of the site that contains the update. The format of the URL is: http(s)://

server_address:port

/

directory

/

filename

. The server address can be either an IP address or a hostname if you have configured a DNS server. For example: http://10.10.99.70/vpnclient-win-4.6.Rel-k9.exe

The directory is optional. You need the port number only if you use ports other than 80 for HTTP or 443 for HTTPS.

For the hardware client: The format of the URL is tftp://

server_address/directory/filename

. The server address can be either an IP address or a hostname if you have configured a DNS server.

For example: tftp://10.1.1.1/vpn3002-4.1.Rel-k9.bin

Edit—Opens the Edit Client Update Entry dialog box, which lets you configure or change client

update parameters. See Edit Client Update Entry

.

Live Client Update—Sends an upgrade notification message to all currently connected VPN clients or selected tunnel group(s).

–

–

Tunnel Group—Selects all or specific tunnel group(s) for updating.

Update Now—Immediately sends an upgrade notification containing a URL specifying where to retrieve the updated software to the currently connected VPN clients in the selected tunnel group or all connected tunnel groups. The message includes the location from which to download the new version of software. The administrator for that VPN client can then retrieve the new software version and update the VPN client software.

For VPN 3002 hardware clients, the upgrade proceeds automatically, with no notification.

You must check

Enable Client Update

for the upgrade to work. Clients that are not connected receive the upgrade notification or automatically upgrade the next time they log on.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Edit Client Update Entry

The Edit Client Update dialog box lets you change information about VPN client revisions and URLs for the indicated client types. The clients must be running one of the revisions specified for the indicated client type. If not, the clients are notified that an upgrade is required.

Fields

•

Client Type—(

Display-only

) Displays the client type selected for editing.

•

VPN Client Revisions—Lets you type a comma-separated list of software or firmware images appropriate for this client. If the user client revision number matches one of the specified revision numbers, there is no need to update the client. If the client is not running a software version on the


OL-20339-01 64-3


Default Tunnel Gateway

•

list, an update is in order. The user of a Windows, MAC OS X, or Linux-based VPN client must download an appropriate software version from the listed URL. The VPN 3002 hardware client software is automatically updated via TFTP.

Image URL—Lets you type the URL for the software/firmware image. This URL must point to a file appropriate for this client.

–

For a Windows, MAC OS X, or Linux-based VPN client, the URL must include the protocol

HTTP or HTTPS and the server address of the site that contains the update. The format of the

URL is: http(s)://

server_address:port

/

directory

/

filename

. The server address can be either an IP address or a hostname if you have configured a DNS server. For example: http://10.10.99.70/vpnclient-win-4.6.Rel-k9.exe

–

The directory is optional. You need the port number only if you use ports other than 80 for HTTP or 443 for HTTPS.

For the hardware client: The format of the URL is tftp://

server_address/directory/filename

. The server address can be either an IP address or a hostname if you have configured a DNS server.

For example: tftp://10.1.1.1/vpn3002-4.1.Rel-k9.bin

The directory is optional.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Default Tunnel Gateway

To configure the default tunnel gateway, click the

Static Route

link. The Configuration > Routing >

Routing > Static Route dialog box opens.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

64-4


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Group Policies

Group Policies

The Group Policies pane lets you manage VPN group policies. A VPN group policy is a collection of user-oriented attribute/value pairs stored either internally on the device or externally on a RADIUS or

LDAP server. Configuring the VPN group policy lets users inherit attributes that you have not configured at the individual group or username level. By default, VPN users have no group policy association. The group policy information is used by VPN tunnel groups and user accounts.

The “child” panes and dialog boxes let you configure the group parameters, including those for the default group. The default group parameters are those that are most likely to be common across all groups and users, and they streamline the configuration task. Groups can “inherit” parameters from this default group, and users can “inherit” parameters from their group or the default group. You can override these parameters as you configure groups and users.

You can configure either an internal or an external group policy. An internal group policy is stored locally, and an external group policy is stored externally on a RADIUS or LDAP server. Clicking Edit opens a similar dialog box on which you can create a new group policy or modify an existing one.

In these dialog boxes, you configure the following kinds of parameters:

•

•

•

General attributes: Name, banner, address pools, protocols, filtering, and connection settings.

Servers: DNS and WINS servers, DHCP scope, and default domain name.

Advanced attributes: Split tunneling, IE browser proxy, SSL VPN client and AnyConnect client, and

IPsec client.

Before configuring these parameters, you should configure:

•

Access hours.

•

•

•

•

Rules and filters.

IPsec Security Associations.

Network lists for filtering and split tunneling

User authentication servers, and specifically the internal authentication server.

Fields

•

Group Policy—Lists the currently configured group policies and Add, Edit, and Delete buttons to help you manage VPN group policies.

–

Name—Lists the name of the currently configured group policies.

–

–

–

–

–

Banner—Allows you to attach a VPN flag or banner.

Type—Lists the type of each currently configured group policy.

Tunneling Protocol—Lists the tunneling protocol that each currently configured group policy uses.

AAA Server Group—Lists the AAA server group, if any, to which each currently configured group policy pertains.

Add—Offers a drop-down menu on which you can select whether to add an internal or an external group policy. If you simply click Add, then by default, you create an internal group policy. Clicking Add opens the Add Internal Group Policy dialog box or the Add External

Group Policy dialog box, which let you add a new group policy to the list. This dialog box includes three menu sections. Click each menu item to display its parameters. As you move from item to item, ASDM retains your settings. When you have finished setting parameters on

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Group Policies


–

–

all menu sections, click

Apply

or

Cancel

. Offers a drop-down menu from which you can select whether to add an internal or an external group policy. If you simply click Add, then by default, you create an internal group policy.

Edit—Displays the Edit Group Policy dialog box, which lets you modify an existing group policy.

Delete—Lets you remove a AAA group policy from the list. There is no confirmation or undo.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add/Edit External Group Policy

The Add or Edit External Group Policy dialog box lets you configure an external group policy.

Fields

•

Name—Identifies the group policy to be added or changed. For Edit External Group Policy, this field is display-only.

•

•

Server Group—Lists the available server groups to which to apply this policy.

Password—Specifies the password for this server group policy.

•

New—Opens a dialog box that lets you select whether to create a new RADIUS server group or a new LDAP server group. Either of these options opens the Add AAA Server Group dialog box.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add AAA Server Group

The Add AAA Server Group dialog box lets you configure a new AAA server group. The Accounting

Mode attribute applies only to RADIUS and TACACS+ protocols.

Fields

•

Server Group—Specifies the name of the server group.

•

Protocol—(

Display only

) Indicates whether this is a RADIUS or an LDAP server group.

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Group Policies

•

•

•

•

Accounting Mode—Indicates whether to use simultaneous or single accounting mode. In single mode, the adaptive security appliance sends accounting data to only one server. In simultaneous mode, the adaptive security appliance sends accounting data to all servers in the group. The

Accounting Mode attribute applies only to RADIUS and TACACS+ protocols.

Reactivation Mode—Specifies the method by which failed servers are reactivated: Depletion or

Timed reactivation mode. In Depletion mode, failed servers are reactivated only after all of the servers in the group become inactive. In Timed mode, failed servers are reactivated after 30 seconds of down time.

Dead Time—Specifies, for depletion mode, the number of minutes (0 through 1440) that must elapse between the disabling of the last server in the group and the subsequent re-enabling of all servers.

The default value is 10 minutes. This field is not available for timed mode.

Max Failed Attempts— Specifies the number (an integer in the range 1 through 5) of failed connection attempts allowed before declaring a nonresponsive server inactive. The default value is

3 attempts.

Adding or Editing a Remote Access Internal Group Policy, General Attributes

The Add or Edit Group Policy dialog box lets you specify tunneling protocols, filters, connection settings, and servers for the group policy being added or modified. For each of the fields on this dialog box, checking the Inherit check box lets the corresponding setting take its value from the default group policy. Inherit is the default value for all of the attributes in this dialog box.

Fields

The following attributes appear in the Add Internal Group Policy > General dialog box. They apply to

SSL VPN and IPsec sessions, or clientless SSL VPN sessions. Thus, several are present for one type of session, but not the other.

•

Name—Specifies the name of this group policy up to 64 characters; spaces are allowed. For the Edit function, this field is read-only.

•

Banner—Specifies the banner text to present to users at login. The length can be up to 491 characters. There is no default value.

The IPsec VPN client supports full HTML for the banner. However, the clientless portal and the

AnyConnect client support partial HTML. To ensure the banner displays properly to remote users, follow these guidelines:

•

•

•

•

–

–

For IPsec client users, use the /n tag.

For AnyConnect client users, use the <BR> tag.

–

For clientless users, use the <BR> tag.

Address Pools—(Network (Client) Access only) Specifies the name of one or more address pools to use for this group policy.

Select—(Network (Client) Access only) Opens the Select Address Pools dialog box, which shows the pool name, starting and ending addresses, and subnet mask of address pools available for client address assignment and lets you select, add, edit, delete, and assign entries from that list.

IPv6 Address Pools—Specifies the name of one or more IPv6 address pools to use for this group policy. The Select button following this field opens the Select Address Pools dialog box, as previously described.

More Options—Displays additional configurable options for this group policy.

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Group Policies


•

Tunneling Protocols—Specifies the tunneling protocols that this group can use. Users can use only the selected protocols. The choices are as follows:

–

–

Clientless SSL VPN—Specifies the use of VPN via SSL/TLS, which uses a web browser to establish a secure remote-access tunnel to a adaptive security appliance; requires neither a software nor hardware client. Clientless SSL VPN can provide easy access to a broad range of enterprise resources, including corporate websites, web-enabled applications, NT/AD file share

(web-enabled), e-mail, and other TCP-based applications from almost any computer that can reach HTTPS Internet sites.

SSL VPN Client—Specifies the use of the Cisco AnyConnect VPN client or the legacy SSL

VPN client. If you are using the AnyConnect client, you must choose this protocol for MUS to be supported.

–

–

IPsec—IP Security Protocol. Regarded as the most secure protocol, IPsec provides the most complete architecture for VPN tunnels. Both Site-to-Site (peer-to-peer) connections and client-to-LAN connections can use IPsec.

L2TP over IPsec—Allows remote users with VPN clients provided with several common PC and mobile PC operating systems to establish secure connections over the public IP network to the security appliance and private corporate networks. L2TP uses PPP over UDP (port 1701) to tunnel the data. The security appliance must be configured for IPsec transport mode.

Note

If you do not select a protocol, an error message appears.

•

•

•

•

•

•

•

•

IPv4Filter—(Network (Client) Access only) Specifies which access control list to use for an IPv4 connection, or whether to inherit the value from the group policy. Filters consist of rules that determine whether to allow or reject tunneled data packets coming through the adaptive security appliance, based on criteria such as source address, destination address, and protocol. To configure filters and rules, see the ACL Manager dialog box.

Manage—Displays the ACL Manager dialog box, with which you can add, edit, and delete Access

Control Lists (ACLs) and Extended Access Control Lists (ACEs). For more information about the

ACL Manager, see the online Help for that dialog box.

IPv6Filter—(Network (Client) Access only) Specifies which access control list to use for an IPv6 connection, or whether to inherit the value from the group policy. Filters consist of rules that determine whether to allow or reject tunneled data packets coming through the adaptive security appliance, based on criteria such as source address, destination address, and protocol. To configure filters and rules, see the ACL Manager dialog box.




NAC Policy—Selects the name of a Network Admission Control policy to apply to this group policy.

You can assign an optional NAC policy to each group policy. The default value is --None--.

Manage—Opens the Configure NAC Policy dialog box. After configuring one or more NAC policies, the NAC policy names appear as options in the drop-down list next to the NAC Policy attribute.

Access Hours—Selects the name of an existing access hours policy, if any, applied to this user or create a new access hours policy. The default value is Inherit, or, if the Inherit check box is not checked, the default value is --Unrestricted--.

Manage—Opens the Browse Time Range dialog box, in which you can add, edit, or delete a time range.

64-8


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Group Policies

•

Simultaneous Logins—Specifies the maximum number of simultaneous logins allowed for this user.

The default value is 3. The minimum value is 0, which disables login and prevents user access.

Note

While there is no maximum limit, allowing several simultaneous connections might compromise security and affect performance.

•

Restrict Access to VLAN—(Optional) Also called “VLAN mapping,” this parameter specifies the egress VLAN interface for sessions to which this group policy applies. The adaptive security appliance forwards all traffic on this group to the selected VLAN. Use this attribute to assign a

VLAN to the group policy to simplify access control. Assigning a value to this attribute is an alternative to using ACLs to filter traffic on a session. In addition to the default value (Unrestricted), the drop-down list shows only the VLANs that are configured on this adaptive security appliance.

Note

This feature works for HTTP connections, but not for FTP and CIFS.

•

•

•

•

•

•

Connection Profile (Tunnel Group) Lock—This parameter permits remote VPN access only with the selected connection profile (tunnel group), and prevents access with a different connection profile.

The default inherited value is None.

Maximum Connect Time—If the Inherit check box is not checked, this parameter specifies the maximum user connection time in minutes. At the end of this time, the system terminates the connection. The minimum is 1 minute, and the maximum is 35791394 minutes (over 4000 years).

To allow unlimited connection time, check Unlimited (the default).

Idle Timeout—If the Inherit check box is not checked, this parameter specifies this user’s idle timeout period in minutes. If there is no communication activity on the user connection in this period, the system terminates the connection. The minimum time is 1 minute, and the maximum time is 10080 minutes. The default is 30 minutes. To allow unlimited connection time, check

Unlimited

.

This value does not apply to Clientless SSL VPN users.

On smart card removal—With the default option, Disconnect, the client tears down the connection if the smart card used for authentication is removed. Click

Keep the connection

if you do not want to require users to keep their smart cards in the computer for the duration of the connection.

Web ACL—(Clientless SSL VPN only) Choose an access control list (ACL) from the drop-down list if you want to filter traffic. Click Manage next to the list if you want to view, modify, add, or remove

ACLs before making a selection.




Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

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64-9


Group Policies

Configuring the Portal for a Group Policy

The Portal attributes determine what appears on the portal page for members of this group policy establishing Clientless SSL VPN connections. In this pane, you can enable Bookmark lists and URL

Entry, file server access, Port Forwarding and Smart Tunnels, ActiveX Relay, and HTTP settings.

Fields

•

Bookmark List—Choose a previously-configured Bookmark list or click

Manage

to create a new one. Bookmarks appear as links, from which users can navigate from the portal page.

•

•

URL Entry—Enable to allow remote users to enter URLs directly into the portal URL field.

File Access Control—Controls the visibility of “hidden shares” for Common Internet File System

(CIFS) files. A hidden share is identified by a dollar sign ($) at the end of the share name. For example, drive C is shared as C$. With hidden shares, a shared folder is not displayed, and users are restricted from browsing or accessing these hidden resources.

–

–

File Server Entry—Enable to allow remote users to enter the name of a file server.

File Server Browsing—Enable to allow remote users to browse for available file servers.

•

•

–

Hidden Share Access—Enable to hide shared folders.

Port Forwarding Control—Provides users access to TCP-based applications over a Clientless SSL

VPN connection through a Java Applet.

–

–

Port Forwarding List—Choose a previously-configured list TCP applications to associate with this group policy. Click

Manage

to create a new list or to edit an existing list.

Auto Applet Download—Enables automatic installation and starting of the Applet the first time the user logs in.

–

Applet Name—Changes the name of the title bar that of the Applet dialog box to the name you designate. By default, the name is Application Access.

Smart Tunnel—Specify your smart tunnel options using a clientless (browser-based) SSL VPN session with the security appliance as the pathway and the security appliance as a proxy server:

–

–

Smart Tunnel Policy—Choose from the network list and specify one of the tunnels options: use smart tunnel for the specified network, do not use smart tunnel for the specified network, or use tunnel for all network traffic. Assigning a smart tunnel network to a group policy or username enables smart tunnel access for all users whose sessions are associated with the group policy or username but restricts smart tunnel access to the applications specified in the list. To view, add, modify, or delete a smart tunnel list, click

Manage

.

Smart Tunnel Application—Choose from the drop-down menu to connect a Winsock 2,

TCP-based application installed on the end station to a server on the intranet. To view, add, modify, or delete a smart tunnel application, click

Manage

.

–

–

Smart Tunnel all Applications—Check this check box to tunnel all applications. All applications are tunneled without choosing from the network list or knowing which executables an end user may invoke for external applications.

Auto Start—Check this check box to start smart tunnel access automatically upon user login.

Uncheck the check box to enable smart tunnel access upon user login but require the user to start it manually, using the Application Access > Start Smart Tunnels button on the Clientless SSL

VPN Portal Page.

64-10


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Group Policies

•

–

Auto Sign-on Server List—Choose the list name from the drop-down menu if you want to reissue the user credentials when the user establishes a smart tunnel connection to a server. Each smart tunnel auto sign-on list entry identifies a server with which to automate the submission of user credentials. To view, add, modify, or delete a smart tunnel auto sign-on list, click

Manage

.

–

Windows Domain Name (Optional)—Specify the Windows domain to add it to the username during auto sign-on, if the universal naming convention (domain\username) is required for authentication. For example, enter CISCO to specify CISCO\qa_team when authenticating for the username qu_team. You must also check the “Use Windows domain name with user name” option when configuring associated entries in the auto sign-on server list.

ActiveX Relay—Lets Clientless users launch Microsoft Office applications from the browser. The applications use the session to download and upload Microsoft Office documents. The ActiveX relay remains in force until the Clientless SSL VPN session closes.

More Options:

•

HTTP Proxy—Enables or disables the forwarding of an HTTP applet proxy to the client. The proxy is useful for technologies that interfere with proper content transformation, such as Java, ActiveX, and Flash. It bypasses mangling while ensuring the continued use of the security appliance.

The forwarded proxy automatically modifies the old browser proxy configuration and redirects all

HTTP and HTTPS requests to the new proxy configuration. It supports virtually all client side technologies, including HTML, CSS, JavaScript, VBScript, ActiveX, and Java. The only browser it supports is Microsoft Internet Explorer.

•

•

Auto Start (HTTP Proxy)—Check to enable HTTP Proxy automatically upon user login. Uncheck to enable smart tunnel access upon user login, but require the user to start it manually.

HTTP Compression—Enables compression of HTTP data over the Clientless SSL VPN session.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Configuring Customization for a Group Policy

To configure customization for a group policy, select a preconfigured portal customization object, or accept the customization provided in the default group policy. You can also configure a URL to display

Fields

•

Portal Customization—Configure a customization object for the end user portal.

–

–

Inherit—To inherit a portal customization from the default group policy, check

Inherit

. To specify a previously configured customization object, uncheck Inherit and choose the customization object from the drop-down list.

Manage—Click to import a new customization object.

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64-11

Group Policies


•

•

Homepage URL (optional)—To specify a homepage URL for users associated with the group policy, enter it in this field. The string must begin with either http:// or https://. To inherit a home page from the default group policy, click

Inherit

. Clientless users are immediately brought to this page after successful authentication. AnyConnect launches the default web browser to this URL upon successful establishment of the VPN connection. On Linux platforms, AnyConnect does not currently support this field and ignores it.

Access Deny Message—To create a message to users for whom access is denied, enter it in this field.

To accept the message in the default group policy, click

Inherit

.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Adding or Editing a Site-to-Site Internal Group Policy

The Add or Edit Group Policy dialog box lets you specify tunneling protocols, filters, connection settings, and servers for the group policy being added or modified. For each of the fields in this dialog box, checking the Inherit check box lets the corresponding setting take its value from the default group policy. Inherit is the default value for all of the attributes on this dialog box.

Fields

The following attributes appear in the Add Internal Group Policy > General dialog box. They apply to

SSL VPN and IPsec sessions, or clientless SSL VPN sessions. Thus, several are present for one type of session, but not the other.

•

Name—Specifies the name of this group policy. For the Edit function, this field is read-only.

•

Tunneling Protocols—Specifies the tunneling protocols that this group can use. Users can use only the selected protocols. The choices are as follows:

–

Clientless SSL VPN—Specifies the use of VPN via SSL/TLS, which uses a web browser to establish a secure remote-access tunnel to a adaptive security appliance; requires neither a software nor hardware client. Clientless SSL VPN can provide easy access to a broad range of enterprise resources, including corporate websites, web-enabled applications, NT/AD file share

(web-enabled), e-mail, and other TCP-based applications from almost any computer that can reach HTTPS Internet sites.

–

–

SSL VPN Client—Specifies the use of the Cisco AnyConnect VPN client or the legacy SSL

VPN client.

IPsec—IP Security Protocol. Regarded as the most secure protocol, IPsec provides the most complete architecture for VPN tunnels. Both Site-to-Site (peer-to-peer) connections and client-to-LAN connections can use IPsec.

–

L2TP/IPsec—Allows remote users with VPN clients provided with several common PC and mobile PC operating systems to establish secure connections over the public IP network to the security appliance and private corporate networks. L2TP uses PPP over UDP (port 1701) to tunnel the data. The security appliance must be configured for IPsec transport mode.

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Group Policies

Note

If you do not select a protocol, an error message appears.

•

•

Filter—(Network (Client) Access only) Specifies which access control list to use, or whether to inherit the value from the group policy. Filters consist of rules that determine whether to allow or reject tunneled data packets coming through the adaptive security appliance, based on criteria such as source address, destination address, and protocol. To configure filters and rules, see the Group

Policy dialog box.




Browse Time Range

Use the Browse Time Range dialog box to add, edit, or delete a time range. A time range is a reusable component that defines starting and ending times that can be applied to a group policy. After defining a time range, you can select the time range and apply it to different options that require scheduling. For example, you can attach an access list to a time range to restrict access to the adaptive security appliance.

A time range consists of a start time, an end time, and optional recurring (that is, periodic) entries. For more information about time ranges, see the online Help for the Add or Edit Time Range dialog box.

Fields

•

Add—Opens the Add Time Range dialog box, in which you can create a new time range.

Note

Creating a time range does not restrict access to the device.

•

•

•

•

•

•

Edit—Opens the Edit Time Range dialog box, in which you can modify an existing time range. This button is active only when you have selected an existing time range from the Browse Time Range table.

Delete—Removes a selected time range from the Browse Time Range table. There is no confirmation or undo of this action.

Name—Specifies the name of the time range.

Start Time—Specifies when the time range begins.

End Time—Specifies when the time range ends.

Recurring Entries—Specifies further constraints of active time of the range within the start and stop time specified.

Modes


Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

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Group Policies

Add/Edit Time Range

The Add or Edit Time Range dialog box lets you configure a new time range.

Fields

•

Time Range Name—Specifies the name that you want to assign to this time range.

•

Start Time—Defines the time when you want the time range to start.

•

•

–

–

Start now—Specifies that the time range starts immediately.

Start at—Selects the month, day, year, hour, and minute at which you want the time range to start.

End Time—Defines the time when you want the time range to end.

–

Never end—Specifies that the time range has no defined end point.

–

End at (inclusive)—Selects the month, day, year, hour, and minute at which you want the time range to end.

Recurring Time Ranges—Constrains the active time of this time range within the start and end times when the time range is active. For example, if the start time is start now and the end time is never end, and you want the time range to be effective every weekday, Monday through Friday, from 8:00

AM to 5:00 PM, you could configure a recurring time range, specifying that it is to be active weekdays from 08:00 through 17:00, inclusive.

•

•

•

Add—Opens the Add Recurring Time Range dialog box, in which you can configure a recurring time range.

Edit—Opens the Edit Recurring Time Range dialog box, in which you can modify a selected recurring time range.

Delete—Removes a selected recurring time range.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit Recurring Time Range

The Add or Edit Recurring Time Range dialog box lets you configure or modify a recurring time range.

Fields

•

Specify days of the week and times on which this recurring range will be active—Makes available the options in the Days of the week area. For example, use this option when you want the time range to be active only every Monday through Thursday, from 08:00 through 16:59.

–

Days of the week—Specifies the days that you want to include in this recurring time range.

Possible options are: Every day, Weekdays, Weekends, and On these days of the week. For the last of these, you can check a check box for each day that you want included in the range.

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ACL Manager

•

–

–

Daily End Time (inclusive)—Specifies the hour and minute, in 24-hour format, when you want the recurring time range to end on each selected day.

Specify a weekly interval when this recurring range will be active—Makes available the options in the Weekly Interval area. The range extends inclusively through the end time. All times in this area are in 24-hour format. For example, use this option when you want the time range to be active continuously from Monday at 8:00 AM through Friday at 4:30 PM.

–

–

Daily Start Time—Specifies the hour and minute, in 24-hour format, when you want the recurring time range to be active on each selected day.

From—Selects the day, hour, and minute when you want the weekly time range to start.

Through—Selects the day, hour, and minute when you want the weekly time range to end.

Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

ACL Manager

The ACL Manager dialog box lets you define access control lists (ACLs) to control the access of a specific host or network to another host/network, including the protocol or port that can be used.


•


•

•


At the end of each ACL, there is an implicit, unwritten rule that denies all traffic that is not permitted. If traffic is not explicitly permitted by an access control entry (ACE), the adaptive security appliance denies it. ACEs are referred to as rules in this section.

Standard ACL

This pane provides summary information about standard ACLs, and lets you add or edit ACLs and ACEs.

Fields

•


•

•

•

•





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64-15

ACL Manager


•

•

•

•

•

•







Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Extended ACL

This pane provides summary information about extended ACLs, and lets you add or edit ACLs and

ACEs.

Fields

•


•


•

•

•

•

•





•

•

•

•



Enabled—Enables or disables a rule. Implicit rules cannot be disabled.

Source—Specifies the IP addresses (Host/Network) that are permitted or denied to send traffic to the IP addresses listed in the Destination column. In detail mode (see the Show Detail radio button), an address column might contain an interface name with the word any, such as inside: any. This means that any host on the inside interface is affected by the rule.

Destination—Specifies the IP addresses (Host/Network) that are permitted or denied to send traffic to the IP addresses listed in the Source column. An address column might contain an interface name with the word any, such as outside: any. This means that any host on the outside interface is affected

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ACL Manager

•

•

•

•

•

by the rule. An address column might also contain IP addresses; for example

209.165.201.1-209.165.201.30. These addresses are translated addresses. When an inside host makes a connection to an outside host, the firewall maps the address of the inside host to an address from the pool. After a host creates an outbound connection, the firewall maintains this address mapping. The address mapping structure is called an xlate, and remains in memory for a period of time. During this time, outside hosts can initiate connections to the inside host using the translated address from the pool, if allowed by the ACL. Normally, outside-to-inside connections require a static translation so that the inside host always uses the same IP address.

Service—Names the service and protocol specified by the rule.


Logging—Shows the logging level and the interval in seconds between log messages (if you enable logging for the ACL). To set logging options, including enabling and disabling logging, right-click this column, and click Edit Log Option. The Log Options dialog box appears.

Time—Specifies the name of the time range to be applied in this rule.


Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit/Paste ACE

The Add/Edit/Paste ACE dialog box lets you create a new extended access list rule, or modify an existing rule. The Paste option becomes available only when you cut or copy a rule.

Fields

•

Action—Determines the action type of the new rule. Select either permit or deny.

–


•

–


Source/Destination—Specifies the source or destination type and, depending on that type, the other relevant parameters describing the source or destination host/network IP Address. Possible values are: any, IP address, Network Object Group, and Interface IP. The availability of subsequent fields depends upon the value of the Type field:

–

–

any—Specifies that the source or destination host/network can be any type. For this value of the

Type field, there are no additional fields in the Source or Destination area.

IP Address—Specifies the source or destination host or network IP address. Both IPv4 and IPv6 addresses are supported. With this selection, the IP Address, ellipsis button, and Netmask fields become available. Choose an IP address or host name from the drop-down list in the IP Address field or click the ellipsis (...) button to browse for an IP address or name. Select a network mask from the drop-down list.

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ACL Manager


•

•

•

–

Network Object Group—Specifies the name of the network object group. Choose a name from the drop-down list or click the ellipsis (...) button to browse for a network object group name.

–

Interface IP—Specifies the interface on which the host or network resides. Select an interface from the drop-down list. The default values are inside and outside. There is no browse function.

Protocol and Service—Specifies the protocol and service to which this ACE filter applies. Service groups let you identify multiple non-contiguous port numbers that you want the ACL to match. For example, if you want to filter HTTP, FTP, and port numbers 5, 8, and 9, define a service group that includes all these ports. Without service groups, you would have to create a separate rule for each port.

You can create service groups for TCP, UDP, TCP-UDP, ICMP, and other protocols. A service group with the TCP-UDP protocol contains services, ports, and ranges that might use either the TCP or

UDP protocol.

–

Protocol—Selects the protocol to which this rule applies. Possible values are ip, tcp, udp, icmp, and other. The remaining available fields in the Protocol and Service area depend upon the protocol you select. The next few bullets describe the consequences of each of these selections:

–

–

Protocol: TCP and UDP—Selects the TCP/UDP protocol for the rule. The Source Port and

Destination Port areas allow you to specify the ports that the ACL uses to match packets.

Source Port/Destination Port—(


) Specifies an operator and a port number, a range of ports, or a well-known service name from a list of services, such as HTTP or FTP. The operator list specifies how the ACL matches the port.

Choose one of the following operators: = (equals the port number), not = (does not equal the port number), > (greater than the port number), < (less than the port number), range (equal to one of the port numbers in the range).

–

–

Group—(


) Selects a source port service group. The

Browse (...) button opens the Browse Source Port or Browse Destination Port dialog box.

Protocol: ICMP—Lets you choose an ICMP type or ICMP group from a preconfigured list or browse (...) for an ICMP group. The Browse button opens the Browse ICMP dialog box.

–

–

Protocol: IP—Specifies the IP protocol for the rule in the IP protocol box. No other fields are available when you make this selection.

Protocol: Other—Lets you choose a protocol from a drop-down list, choose a protocol group from a drop-down list, or browse for a protocol group. The Browse (...) button opens the Browse

Other dialog box.

Rule Flow Diagram—(

Display only

) Provides a graphical representation of the configured rule flow.

This same diagram appears on the ACL Manager dialog box unless you explicitly close that display.

Options—Sets optional features for this rule, including logging parameters, time ranges, and description.

–

–

Logging—Enables or disables logging or specifies the use of the default logging settings. If logging is enabled, the Syslog Level and Log Interval fields become available.

Syslog Level—Selects the level of logging activity. The default is Informational.

–

–

Log Interval—Specifies the interval for permit and deny logging. The default is 300 seconds.

The range is 1 through 6000 seconds.

Time Range—Selects the name of the time range to use with this rule. The default is (any). Click the Browse (...) button to open the Browse Time Range dialog box to select or add a time range.

–

Description—(

Optional

) Provides a brief description of this rule. A description line can be up to 100 characters long, but you can break a description into multiple lines.

64-18


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Modes


ACL Manager

Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Browse Source/Destination Address

The Browse Source or Destination Address dialog box lets you select an object to use as a source or destination for this rule.

Fields

•

Type—Determines the type of object to use as the source or destination for this rule. Selections are

IP Address Objects, IP Names, Network Object Groups, and All. The contents of the table following this field change, depending upon your selection.

•

Source/Destination Object Table—Displays the objects from which you can select a source or destination object. If you choose All in the type field, each category of object appears under its own heading. The table has the following headings:

–

–

–

–

Name—Displays the network name (which may be an IP address) for each object.

IP address—Displays the IP address of each object.

Netmask—Displays the network mask to use with each object.

Description—Displays the description entered in the Add/Edit/Paste Extended Access List Rule dialog box.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Browse Source/Destination Port

The Browse Source or Destination Port dialog box lets you select a source or destination port for this protocol in this rule.

Fields

•

Add—Opens the Add TCP Service Group dialog box, in which you can configure a new TCP service group.

•

Find—Opens the Filter field.

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ACL Manager


•

•

•

Filter/Clear—Specifies a filter criterion that you can use to search for items in the Name list, thus displaying only those items that match that criterion. When you make an entry in the Filter field, the

Filter button becomes active. Clicking the Filter button performs the search. After you perform the search, the Filter button is dimmed, and the Clear button becomes active. Clicking the Clear button clears the filter field and dims the Clear button.

Type—Determines the type of object to use as the source or destination for this rule. Selections are

IP Address Objects, IP Names, Network Object Groups, and All. The contents of the table following this field change, depending upon your selection.

Name—Lists the predefined protocols and service groups for your selection.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add TCP Service Group

The Add TCP Service Group dialog box lets you configure a new a TCP service group or port to add to the browsable source or destination port list for this protocol in this rule. Selecting a member of either the Members not in Group or the Members in Group list activates the Add and Remove buttons.

•

•

•

Fields

•

Group Name—Specifies the name of the new TCP service group.

•

•

Description—(Optional) Provides a brief description of this group.

Members not in Group—Presents the option to select either a service/service group or a port number to add to the Members in Group list.

•

•

Service/Service Group—Selects the option to select the name of a TCP service or service group to add to the Members in Group list.

Port #—Selects the option to specify a range of port numbers to add to the Members in Group list.

Add—Moves a selected item from the Members not in Group list to the Members in Group list.

Remove—Moves a selected item from the Members in Group list to the Members not in Group list.

Members in Group—Lists the members already configured in this service group.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

64-20


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ACL Manager

Browse ICMP

The Browse ICMP dialog box lets you select an ICMP group for this rule.

Fields

•

Add—Opens the Add ICMP Group dialog box, in which you can configure a new TCP service group.

•

•




•

•

Type—Determines the type of object to use as the ICMP group for this rule. Selections are IP

Address Objects, IP Names, Network Object Groups, and All. The contents of the table following this field change, depending upon your selection.

Name—Lists the predefined ICMP groups for your selection.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add ICMP Group

The Add ICMP Group dialog box lets you configure a new a ICMP group by name or by number to add to the browsable ICMP list for this protocol in this rule. Choosing a member of either the Members not in Group or the Members in Group list activates the Add and Remove buttons.

Fields

•


•

•


Members not in Group—Presents the option to select either an ICMP type/ICMP group or an ICMP number to add to the Members in Group list.

•

•

•

•

•

ICMP Type/ICMP Group—Selects the option to select the name of an ICMP group to add to the

Members in Group list.

ICMP #—Selects the option to specify an ICMP member by number to add to the Members in Group list.




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64-21


ACL Manager

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Browse Other

The Browse Other dialog box lets you select a protocol group for this rule.

Fields

•

Add—Opens the Add Protocol Group dialog box, in which you can configure a new service group.

•


•

•

•



Type—Determines the type of object to use as the protocol group for this rule. Selections are IP

Address Objects, IP Names, Network Object Groups, and All. The contents of the table following this field change, depending upon your selection.

Name—Lists the predefined protocol groups for your selection.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add Protocol Group

The Add Protocol Group dialog box lets you configure a new a protocol group by name or by number to add to the browsable protocol list for this rule. Selecting a member of either the Members not in Group or the Members in Group list activates the Add and Remove buttons.

Fields

•


•

•


Members not in Group—Presents the option to select either a protocol/protocol group or a protocol number to add to the Members in Group list.

64-22


OL-20339-01


ACL Manager

•

•

•

•

•

Protocol/Protocol Group—Selects the option to select the name of a protocol or protocol group to add to the Members in Group list.

Protocol #—Selects the option to specify a protocol by number to add to the Members in Group list.




Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add/Edit Internal Group Policy > Servers

The Add or Edit Group Policy dialog box, Servers item lets you specify DNS and WINS servers, as well as the DHCP scope and default domain.

Login Setting

In this dialog box, you can enable the adaptive security appliance to prompt remote users to download the AnyConnect client.

Figure 64-1 shows the prompt displayed:

Figure 64-1 Prompt Displayed to Remote Users for SSL VPN Client Download

OL-20339-01

Fields

•

Post Login Setting—Choose to prompt the user and set the timeout to perform the default post login selection.

•

Default Post Login Selection—Choose an action to perform after login.

Modes



64-23


ACL Manager

Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Client Firewall

Client Firewall allows you to choose a rule from AnyConnect SSL VPN or IPSec clients that have been defined in the device. You can set the rules for either IPv4 or IPv6. To manage the ACLs, click

Manage

for a list of existing IPsec client firewalls in the group policy editor.

Note

This feature requires an AnyConnect release that supports the Cisco Secure Mobility solution.

Fields

•

Public Network Rule—Use the drop-down list to choose from the existing defined ACLs.

•

•

•


Control Lists (ACLs) and Extended Access Control Lists (ACEs).

Private Network Rule—Use the drop-down list to choose from the existing defined ACLs.


Control Lists (ACLs) and Extended Access Control Lists (ACEs).

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Key Regeneration

Rekey Negotiation occurs when the security appliance and the client perform a rekey and they renegotiate the crypto keys and initialization vectors, increasing the security of the connection.

Fields

•

Renegotiation Interval—Uncheck the Unlimited check box to specify the number of minutes from the start of the session until the rekey takes place, from 1 to 10080 (1 week).

•

Renegotiation Method—Check the

None

check box to disable rekey, check the

SSL

check box to specify SSL renegotiation during a rekey, or check the

New Tunnel

check box to establish a new tunnel during rekey.

Modes


64-24


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ACL Manager

Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Dead Peer Detection

Dead Peer Detection (DPD) ensures that the security appliance (gateway) or the client can quickly detect a condition where the peer is not responding, and the connection has failed.

Fields

•

Gateway Side Detection—Uncheck the

Disable

check box to specify that DPD is performed by the security appliance (gateway). Enter the interval, from 30 to 3600 seconds, with which the security appliance performs DPD.

•

Client Side Detection—Uncheck the

Disable

check box to specify that DPD is performed by the client. Enter the interval, from 30 to 3600 seconds, with which the client performs DPD.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Customization

Fields

•

Portal Customization—Selects the customization to apply to the AnyConnect Client/SSL VPN portal page. The default is DfltCustomization.

•

Manage—Opens the Configure GUI Customization objects dialog box, in which you can specify that you want to add, edit, delete, import, or export a customization object.

•

Access Deny Message—Specifies a message to display to the end user when the connection is denied. Select Inherit to accept the message in the default group policy. The default message, if you deselect Inherit, is: “Login was successful, but because certain criteria have not been met or due to some specific group policy, you do not have permission to use any of the VPN features. Contact your

IT administrator for more information.”

Modes


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64-25

ACL Manager

ACLs


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

This dialog box lets you configure ACLs for Clientless SSL VPN.

Fields

•

View (Unlabeled)—Indicates whether the selected entry is expanded (minus sign) or contracted

(plus sign).

•

•

# column—Specifies the ACE ID number.

Enable—Indicates whether this ACL is enabled or disabled. You can enable or disable the ACL using this check box.

•

•

•

•

•

Action—Specifies whether this ACL permits or denies access.

Type—Specifies whether this ACL applies to a URL or a TCP address/port.

Filter—Specifies the type of filter being applied.

Syslog Level (Interval)—Specifies the syslog parameters for this ACL.

•

•

•

Time Range—Specifies the name of the time range, if any, for this ACL. The time range can be a single interval or a series of periodic ranges.

Description—Specifies the description, if any, of the ACL.

Add ACL—Displays the Add Web Type ACL dialog box, in which you can specify an ACL ID.

Add ACE—Displays the Add Web Type ACE dialog box, in which you specify parameters for the named ACL. This button is active only if there are one or more entries in the Web Type ACL table.

•

•

Edit ACE/Delete—Click to edit or delete the highlighted ACL or ACE. When you delete an ACL, you also delete all of its ACEs. No warning or undelete.

Move Up/Move Down—Highlight an ACL or ACE and click these buttons to change the order of

ACLs and ACEs. The adaptive security appliance checks ACLs and their ACEs in priority order according to their position in the ACLs list box until it finds a match.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

64-26


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ACL Manager

Add/Edit Internal Group Policy > IPsec Client

The Add or Edit Group Policy > IPsec dialog box lets you specify tunneling protocols, filters, connection settings, and servers for the group policy being added or modified.

Fields

•

Re-Authentication on IKE Re-key—Enables or disables reauthentication when IKE re-key occurs, unless the Inherit check box is checked. The user has 30 seconds to enter credentials, and up to three attempts before the SA expires at approximately two minutes and the tunnel terminates.

•

•

•

Allow entry of authentication credentials until SA expires—Allow users the time to reenter authentication credentials until the maximum lifetime of the configured SA.

IP Compression—Enables or disables IP Compression, unless the Inherit check box is checked.

•

Perfect Forward Secrecy—Enables or disables perfect forward secrecy (PFS), unless the Inherit check box is selected. PFS ensures that the key for a given IPsec SA was not derived from any other secret (like some other keys). In other words, if someone were to break a key, PFS ensures that the attacker would not be able to derive any other key. If PFS were not enabled, someone could hypothetically break the IKE SA secret key, copy all the IPsec protected data, and then use knowledge of the IKE SA secret to compromise the IPsec SAs set up by this IKE SA. With PFS, breaking IKE would not give an attacker immediate access to IPsec. The attacker would have to break each IPsec SA individually.

Store Password on Client System—Enables or disables storing the password on the client system.

Note

Storing the password on a client system can constitute a potential security risk.

•

•

•

•

IPsec over UDP—Enables or disables using IPsec over UDP.

IPsec over UDP Port—Specifies the UDP port to use for IPsec over UDP.

Tunnel Group Lock—Enables locking the tunnel group you select from the list, unless the Inherit check box or the value None is selected.

IPsec Backup Servers—Activates the Server Configuration and Server IP Addresses fields, so you can specify the UDP backup servers to use if these values are not inherited.

–

Server Configuration—Lists the server configuration options to use as an IPsec backup server.

The available options are: Keep Client Configuration (the default), Use the Backup Servers

Below, and Clear Client Configuration.

–

Server Addresses (space delimited)—Specifies the IP addresses of the IPsec backup servers.

This field is available only when the value of the Server Configuration selection is Use the

Backup Servers Below.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

OL-20339-01


64-27


ACL Manager

Client Access Rules

The Client Access Rules table on this dialog box lets you view up to 25 client access rules. If you uncheck the Inherit check box, the Add, Edit, and Delete buttons become active and the following column headings appear in the table:

–

Priority—Shows the priority for this rule.

–

–

Action—Specifies whether this rule permits or denies access.

Client Type—Specifies the type of VPN client to which this rule applies, software or hardware, and for software clients, all Windows clients or a subset.

–

VPN Client Version—Specifies the version or versions of the VPN client to which this rule applies. This column contains a comma-separated list of software or firmware images appropriate for this client.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit Client Access Rule

The Add or Edit Client Access Rule dialog box adds a new client access rule for an IPsec group policy or modifies an existing rule.

Fields

•

Priority—Shows the priority for this rule.

•

Action—Specifies whether this rule permits or denies access.

•

•

VPN Client Type—Specifies the type of VPN client to which this rule applies, software or hardware, and for software clients, all Windows clients or a subset. Some common values for VPN Client Type include VPN 3002, PIX, Linux, * (matches all client types), Win9x (matches Windows 95, Windows

98, and Windows ME), and WinNT (matches Windows NT, Windows 2000, and Windows XP). If you choose *, do not configure individual Windows types such as Windows NT.

VPN Client Version—Specifies the version or versions of the VPN client to which this rule applies.

This box contains a comma-separated list of software or firmware images appropriate for this client.

The following caveats apply:

–

–

You must specify the software version for this client. You can specify

*

to match any version.

Your entries must match exactly those on the URL for the VPN client, or the TFTP server for the VPN 3002.

–

–

The TFTP server for distributing the hardware client image must be a robust TFTP server.

If the client is already running a software version on the list, it does not need a software update.

If the client is not running a software version on the list, an update is in order.

–

A VPN client user must download an appropriate software version from the listed URL.

64-28


OL-20339-01


–

The VPN 3002 hardware client software is automatically updated via TFTP.

Modes


ACL Manager

Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add/Edit Internal Group Policy > Client Configuration Dialog Box

The Add or Edit Group Policy dialog box, Client Configuration dialog box contains three tabs that let you configure general client parameters, Cisco client parameters, and Microsoft client parameters.

For information about the individual dialog boxes, see the following links:

•

Add/Edit Internal Group Policy > Client Configuration > General Client Parameters, page 64-29

•

•

Add/Edit Internal Group Policy > Client Configuration > Cisco Client Parameters, page 64-31

Add or Edit Internal Group Policy > Advanced > IE Browser Proxy, page 64-32

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add/Edit Internal Group Policy > Client Configuration > General Client Parameters

This dialog box configures client attributes that are common across both Cisco and Microsoft clients, including the banner text, default domain, split tunnel parameters, and address pools.

Note

The AnyConnect VPN client and the SSL VPN client do not support split DNS.

Fields

•

Inherit—(Multiple instances) Indicates that the corresponding setting takes its value from the default group policy. Unchecking the Inherit check box makes other options available for the parameter. This is the default option for all attributes on this tab.

•

Banner—Specifies whether to inherit the banner from the default group policy or enter new banner text. To insert a new line in a paragraph, use the /n tag. For more information, see

View/Config

Banner

.

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64-29

ACL Manager


•

•

•

•

•

•

•

The IPsec VPN client supports full HTML for the banner. However, the clientless portal and the

AnyConnect client support partial HTML. To ensure the banner displays properly to remote users, follow these guidelines:

–

–

For IPsec client users, use the /n tag.

For AnyConnect client users, use the <BR> tag.

–

For clientless users, use the <BR> tag.

Edit Banner—Displays the View/Config Banner dialog box, in which you can enter banner text, up to 500 characters.

Default Domain—Specifies whether to inherit the default domain from the default group policy or use a new default domain specified in the field.

Split Tunnel DNS Names (space delimited)—Specifies whether to inherit the split-tunnel DNS names or from the default group policy or specify a new name or list of names in the field.

Split Tunnel Policy—Specifies whether to inherit the split-tunnel policy from the default group policy or select a policy from the menu. The menu options are to tunnel all networks, tunnel those in the network list below, or exclude those in the network list below.

Split Tunnel Network List—Specifies whether to inherit the split-tunnel network list from the default group policy or choose from the drop-down list.

Manage—Opens the ACL Manager dialog box, in which you can manage standard and extended access control lists.

Address Pools—Configures the address pools available through this group policy.

–

–

Available Pools—Specifies a list of address pools for allocating addresses to remote clients.

Unchecking the Inherit check box with no address pools in the Assigned Pools list indicates that no address pools are configured and disables inheritance from other sources of group policy.

Add—Moves the name of an address pool from the Available Pools list to the Assigned Pools list.

–

–

Remove—Moves the name of an address pool from the Assigned Pools list to the Available

Pools list.

Assigned Pools (up to 6 entries)—Lists the address pools you have added to the assigned pools list. The address-pools settings in this table override the local pool settings in the group. You can specify a list of up to six local address pools to use for local address allocation. The order in which you specify the pools is significant. The adaptive security appliance allocates addresses from these pools in the order in which the pools appear in this command.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

64-30


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ACL Manager

View/Config Banner

The View/Config Banner dialog box lets you enter up to 500 characters of text in the text field to display as a banner for the specified client.

Note

A carriage return/line feed, created by pressing Enter, counts as 2 characters.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit Internal Group Policy > Client Configuration > Cisco Client Parameters

This dialog box configures client attributes that are specific to Cisco clients, including password storage, enabling or disabling IPsec over UDP and setting the UDP port number, and configuring IPsec backup servers.

Fields

•

Store Password on Client System—Enables or disables storing the password on the client system.

Note

Storing the password on a client system can constitute a potential security risk.

•

•

•

•

•

IPsec over UDP—Enables or disables using IPsec over UDP.

IPsec over UDP Port—Specifies the UDP port to use for IPsec over UDP.

IPsec Backup Servers—Activates the Server Configuration and Server IP Addresses fields, so you can specify the UDP backup servers to use if these values are not inherited.

Server Configuration—Lists the server configuration options to use as an IPsec backup server. The available options are: Keep Client Configuration (the default), Use the Backup Servers Below, and

Clear Client Configuration.

Server Addresses (space delimited)—Specifies the IP addresses of the IPsec backup servers. This field is available only when the value of the Server Configuration selection is Use the Backup

Servers Below.

Modes


OL-20339-01


64-31


ACL Manager

Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add or Edit Internal Group Policy > Advanced > IE Browser Proxy

This dialog box configures attributes for Microsoft Internet Explorer.

Fields

•

Proxy Server Policy—Configures the Microsoft Internet Explorer browser proxy actions

(“methods”) for a client PC.

–

Do not modify client proxy settings—Leaves the HTTP browser proxy server setting in Internet

Explorer unchanged for this client PC.

–

–

Do not use proxy—Disables the HTTP proxy setting in Internet Explorer for the client PC.

Select proxy server settings from the following—Enables the following check boxes for your selections: Auto detect proxy, Use proxy server settings given below, and Use proxy auto configuration (PAC) given below.

•

•

–

–

Auto detect proxy—Enables the use of automatic proxy server detection in Internet Explorer for the client PC.

Use proxy server settings specified below—Sets the HTTP proxy server setting in Internet

Explorer to use the value configured in the Proxy Server Name or IP Address field.

–

Use proxy auto configuration (PAC) given below—Specifies the use of the file specified in the

Proxy Auto Configuration (PAC) field as the source for auto configuration attributes.

Proxy Server Settings—Configures the proxy server parameters for Microsoft clients using

Microsoft Internet Explorer.

–

–

Server Address and Port—Specifies the IP address or name and the port of an Microsoft Internet

Explorer server that is applied for this client PC.

Bypass Proxy Server for Local Addresses—Configures Microsoft Internet Explorer browser proxy local-bypass settings for a client PC. Click

Yes

to enable local bypass or

No

to disable local bypass.

–

Exception List—Lists the server names and IP addresses that you want to exclude from proxy server access. Enter the list of addresses that you do not want to have accessed through a proxy server. This list corresponds to the Exceptions list in the Proxy Settings dialog box in Internet

Explorer.

PAC URL—Specifies the URL of the auto-configuration file. This file tells the browser where to look for proxy information. To use the proxy auto-configuration (PAC) feature, the remote user must use the Cisco AnyConnect VPN client.

Many network environments define HTTP proxies that connect a web browser to a particular network resource. The HTTP traffic can reach the network resource only if the proxy is specified in the browser and the client routes the HTTP traffic to the proxy. SSLVPN tunnels complicate the definition of HTTP proxies because the proxy required when tunneled to an enterprise network can differ from that required when connected to the Internet via a broadband connection or when on a third-party network.

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In addition, companies with large networks might need to configure more than one proxy server and let users choose between them, based on transient conditions. By using .pac files, an administrator can author a single script file that determines which of numerous proxies to use for all client computers throughout the enterprise.

The following are some examples of how you might use a PAC file:

–

Choosing a proxy at random from a list for load balancing.

–

–

Rotating proxies by time of day or day of the week to accommodate a server maintenance schedule.

Specifying a backup proxy server to use in case the primary proxy fails.

–

Specifying the nearest proxy for roaming users, based on the local subnet.

You can use a text editor to create a proxy auto-configuration (.pac) file for your browser. A .pac file is a JavaScript file that contains logic that specifies one or more proxy servers to be used, depending on the contents of the URL. Use the PAC URL field to specify the URL from which to retrieve the

.pac file. Then the browser uses the .pac file to determine the proxy settings. For details about .pac files, see the following Microsoft Knowledge Base article: http://www.microsoft.com/mind/0599/faq/faq0599.asp

.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add/Edit Standard Access List Rule

The Add/Edit Standard Access List Rule dialog box lets you create a new rule, or modify an existing rule.

Fields

•

Action—Determines the action type of the new rule. Choose either Permit or Deny.

–

–



•

•

Host/Network IP Address—Identifies the networks by IP address.

–

IP address—The IP address of the host or network.

–

Mask—The subnet mask of the host or network

Description—(Optional) Enter a description of the access rule.

Modes


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ACL Manager

Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit Internal Group Policy > Client Firewall

The Add or Edit Group Policy Client Firewall dialog box lets you configure firewall settings for VPN clients for the group policy being added or modified.

Note

Only VPN clients running Microsoft Windows can use these firewall features. They are currently not available to hardware clients or other (non-Windows) software clients.

A

firewall

isolates and protects a computer from the Internet by inspecting each inbound and outbound individual packet of data to determine whether to allow or drop it. Firewalls provide extra security if remote users in a group have split tunneling configured. In this case, the firewall protects the user’s PC, and thereby the corporate network, from intrusions by way of the Internet or the user’s local LAN.

Remote users connecting to the adaptive security appliance with the VPN client can choose the appropriate firewall option.

In the first scenario, a remote user has a personal firewall installed on the PC. The VPN client enforces firewall policy defined on the local firewall, and it monitors that firewall to make sure it is running. If the firewall stops running, the VPN client drops the connection to the adaptive security appliance. (This firewall enforcement mechanism is called

Are You There (AYT)

, because the VPN client monitors the firewall by sending it periodic “are you there?” messages; if no reply comes, the VPN client knows the firewall is down and terminates its connection to the adaptive security appliance.) The network administrator might configure these PC firewalls originally, but with this approach, each user can customize his or her own configuration.

In the second scenario, you might prefer to enforce a centralized firewall policy for personal firewalls on VPN client PCs. A common example would be to block Internet traffic to remote PCs in a group using split tunneling. This approach protects the PCs, and therefore the central site, from intrusions from the

Internet while tunnels are established. This firewall scenario is called

push policy

or

Central Protection

Policy (CPP)

. On the adaptive security appliance, you create a set of traffic management rules to enforce on the VPN client, associate those rules with a filter, and designate that filter as the firewall policy. The adaptive security appliance pushes this policy down to the VPN client. The VPN client then in turn passes the policy to the local firewall, which enforces it.

Fields

•

Inherit—Determines whether the group policy obtains its client firewall setting from the default group policy. This option is the default setting. When set, it overrides the remaining attributes in this dialog boxing dims their names.

•

Client Firewall Attributes—Specifies the client firewall attributes, including what type of firewall

(if any) is implemented and the firewall policy for that firewall.

•

Firewall Setting—Lists whether a firewall exists, and if so, whether it is required or optional. If you select No Firewall (the default), none of the remaining fields on this dialog box are active. If you want users in this group to be firewall-protected, select either the Firewall Required or Firewall

Optional setting.

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If you choose Firewall Required, all users in this group must use the designated firewall. The adaptive security appliance drops any session that attempts to connect without the designated, supported firewall installed and running. In this case, the adaptive security appliance notifies the

VPN client that its firewall configuration does not match.

Note

If you require a firewall for a group, make sure the group does not include any clients other than

Windows VPN clients. Any other clients in the group (including ASA 5505 in client mode and

VPN 3002 hardware clients) are unable to connect.

•

•

•

If you have remote users in this group who do not yet have firewall capacity, choose Firewall

Optional. The Firewall Optional setting allows all the users in the group to connect. Those who have a firewall can use it; users that connect without a firewall receive a warning message. This setting is useful if you are creating a group in which some users have firewall support and others do not—for example, you may have a group that is in gradual transition, in which some members have set up firewall capacity and others have not yet done so.

Firewall Type—Lists firewalls from several vendors, including Cisco. If you select Custom Firewall, the fields under Custom Firewall become active. The firewall you designate must correlate with the firewall policies available. The specific firewall you configure determines which firewall policy options are supported.

Custom Firewall—Specifies the vendor ID, Product ID and description for the custom firewall.

–

–

–

Vendor ID—Specifies the vendor of the custom firewall for this group policy.

Product ID—Specifies the product or model name of the custom firewall being configured for this group policy.

Description—(Optional) Describes the custom firewall.

Firewall Policy—Specifies the type and source for the custom firewall policy.

–

–

Policy defined by remote firewall (AYT)—Specifies that the firewall policy is defined by the remote firewall (Are You There). Policy defined by remote firewall (AYT) means that remote users in this group have firewalls located on their PCs. The local firewall enforces the firewall policy on the VPN client. The adaptive security appliance allows VPN clients in this group to connect only if they have the designated firewall installed and running. If the designated firewall is not running, the connection fails. Once the connection is established, the VPN client polls the firewall every 30 seconds to make sure that it is still running. If the firewall stops running, the

VPN client ends the session.

Policy pushed (CPP)—Specifies that the policy is pushed from the peer. If you choose this option, the Inbound Traffic Policy and Outbound Traffic Policy lists and the Manage button become active. The adaptive security appliance enforces on the VPN clients in this group the traffic management rules defined by the filter you choose from the Policy Pushed (CPP) drop-down menu. The choices available on the menu are filters defined on this adaptive security appliance, including the default filters. Keep in mind that the adaptive security appliance pushes these rules down to the VPN client, so you should create and define these rules relative to the

VPN client, not the adaptive security appliance. For example, “in” and “out” refer to traffic coming into the VPN client or going outbound from the VPN client. If the VPN client also has a local firewall, the policy pushed from the adaptive security appliance works with the policy of the local firewall. Any packet that is blocked by the rules of either firewall is dropped.

–

–

Inbound Traffic Policy—Lists the available push policies for inbound traffic.

Outbound Traffic Policy—Lists the available push policies for outbound traffic.

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ACL Manager


–

Manage—Displays the ACL Manager dialog box, in which you can configure Access Control

Lists (ACLs).

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add/Edit Internal Group Policy > Hardware Client

The Add or Edit Group Policy > Hardware Client dialog box lets you configure settings for the VPN

3002 hardware client for the group policy being added or modified. The Hardware Client dialog box parameters do not pertain to the ASA 5505 in client mode.

Fields

•

Inherit—(Multiple instances) Indicates that the corresponding setting takes its value from the default group policy, rather than from the explicit specifications that follow. This is the default setting for all attributes in this dialog box.

•

Require Interactive Client Authentication—Enables or disables the requirement for interactive client authentication. This parameter is disabled by default. Interactive hardware client authentication provides additional security by requiring the VPN 3002 to authenticate with a username and password that you enter manually each time the VPN 3002 initiates a tunnel. With this feature enabled, the VPN 3002 does not have a saved username and password. When you enter the username and password, the VPN 3002 sends these credentials to the adaptive security appliance to which it connects. The adaptive security appliance facilitates authentication, on either the internal or an external authentication server. If the username and password are valid, the tunnel is established.

When you enable interactive hardware client authentication for a group, the adaptive security appliance pushes that policy to the VPN 3002s in the group. If you have previously set a username and password on the VPN 3002, the software deletes them from the configuration file. When you try to connect, the software prompts you for a username and password.

•

If, on the adaptive security appliance, you subsequently disable interactive hardware authentication for the group, it is enabled locally on the VPN 3002s, and the software continues to prompt for a username and password. This lets the VPN 3002 connect, even though it lacks a saved username and password, and the adaptive security appliance has disabled interactive hardware client authentication. If you subsequently configure a username and password, the feature is disabled, and the prompt no longer appears. The VPN 3002 connects to the adaptive security appliance using the saved username and password.

Require Individual User Authentication—Enables or disables the requirement for individual user authentication for users behind ASA 5505 in client mode or the VPN 3002 hardware client in the group. To display a banner to hardware clients in a group, individual user authentication must be enabled. This parameter is disabled by default.

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Individual user authentication protects the central site from access by unauthorized persons on the private network of the hardware client. When you enable individual user authentication, each user that connects through a hardware client must open a web browser and manually enter a valid username and password to access the network behind the adaptive security appliance, even though the tunnel already exists.

Note

You cannot use the command-line interface to log in if user authentication is enabled. You must use a browser.

•

•

If you have a default home page on the remote network behind the adaptive security appliance, or if you direct the browser to a website on the remote network behind the adaptive security appliance, the hardware client directs the browser to the proper pages for user login. When you successfully log in, the browser displays the page you originally entered.

If you try to access resources on the network behind the adaptive security appliance that are not web-based, for example, e-mail, the connection fails until you authenticate using a browser.

To authenticate, you must enter the IP address for the private interface of the hardware client in the browser Location or Address field. The browser then displays the login dialog box for the hardware client. To authenticate, click Connect/Login Status.

One user can log in for a maximum of four sessions simultaneously. Individual users authenticate according to the order of authentication servers configured for a group.

User Authentication Idle Timeout—Configures a user timeout period. The security appliance terminates the connection if it does not receive user traffic during this period. You can specify that the timeout period is a specific number of minutes or unlimited.

–

Unlimited—Specifies that the connection never times out. This option prevents inheriting a value from a default or specified group policy.

–

Minutes—Specifies the timeout period in minutes. Use an integer between 1 and 35791394. The default value is Unlimited.

Note that the idle timeout indicated in response to the show uauth command is always the idle timeout value of the user who authenticated the tunnel on the Cisco Easy VPN remote device.

Cisco IP Phone Bypass—Lets Cisco IP Phones bypass the interactive individual user authentication processes. If enabled, interactive hardware client authentication remains in effect. Cisco IP Phone

Bypass is disabled by default.

Note

You must configure the ASA 5505 in client mode or the VPN 3002 hardware client to use network extension mode for IP phone connections.

•

LEAP Bypass—Lets LEAP packets from Cisco wireless devices bypass the individual user authentication processes (if enabled). LEAP Bypass lets LEAP packets from devices behind a hardware client travel across a VPN tunnel

prior

to individual user authentication. This lets workstations using Cisco wireless access point devices establish LEAP authentication. Then they authenticate again per individual user authentication (if enabled). LEAP Bypass is disabled by default.

Note

This feature does not work as intended if you enable interactive hardware client authentication.

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ACL Manager


IEEE 802.1X is a standard for authentication on wired and wireless networks. It provides wireless

LANs with strong mutual authentication between clients and authentication servers, which can provide dynamic per-user, per-session wireless encryption privacy (WEP) keys, removing administrative burdens and security issues that are present with static WEP keys.

Cisco Systems has developed an 802.1X wireless authentication type called Cisco LEAP. LEAP implements mutual authentication between a wireless client on one side of a connection and a

RADIUS server on the other side. The credentials used for authentication, including a password, are always encrypted before they are transmitted over the wireless medium.

Note

Cisco LEAP authenticates wireless clients to RADIUS servers. It does not include RADIUS accounting services.

LEAP users behind a hardware client have a circular dilemma: they cannot negotiate LEAP authentication because they cannot send their credentials to the RADIUS server behind the central site device over the tunnel. The reason they cannot send their credentials over the tunnel is that they have not authenticated on the wireless network. To solve this problem, LEAP Bypass lets LEAP packets, and only LEAP packets, traverse the tunnel to authenticate the wireless connection to a

RADIUS server before individual users authenticate. Then the users proceed with individual user authentication.

LEAP Bypass works as intended under the following conditions:

–

–

–

The interactive unit authentication feature (intended for wired devices) must be disabled. If interactive unit authentication is enabled, a non-LEAP (wired) device must authenticate the hardware client before LEAP devices can connect using that tunnel.

Individual user authentication is enabled (if it is not, you do not need LEAP Bypass).

Access points in the wireless environment must be Cisco Aironet Access Points. The wireless

NIC cards for PCs can be other brands.

–

The Cisco Aironet Access Point must be running Cisco Discovery Protocol (CDP).

–

–

The ASA 5505 or VPN 3002 can operate in either client mode or network extension mode.

LEAP packets travel over the tunnel to a RADIUS server via ports 1645 or 1812.

Note

Allowing any unauthenticated traffic to traverse the tunnel might pose a security risk.

•

Allow C—Restricts the use of Network Extension Mode on the hardware client. Choose the option to let hardware clients use Network Extension Mode. Network Extension Mode is required for the hardware client to support IP phone connections, because the Call Manager can communicate only with actual IP addresses.

Note

If you disable network extension mode, the default setting, the hardware client can connect to this adaptive security appliance in PAT mode only. If you disallow network extension mode here, be careful to configure all hardware clients in a group for PAT mode. If a hardware client is configured to use Network Extension Mode and the adaptive security appliance to which it connects disables Network Extension Mode, the hardware client attempts to connect every 4 seconds, and every attempt is rejected. In this situation, the hardware client puts an unnecessary processing load on the adaptive security appliance to which it connects; large numbers of hardware clients that are misconfigured in this way reduces the ability of the security appliance to provide service.

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Configuring AnyConnect (SSL) VPN Client Connections

Modes


Add/Edit Server and URL List

The Add or Edit Server and URL List dialog box lets you add, edit, delete, and order the items in the designated URL list.

Fields

•

List Name—Specifies the name of the list to be added or selects the name of the list to be modified or deleted.

•

URL Display Name—Specifies the URL name displayed to the user.

•

•

•

•

•

URL—Specifies the actual URL associated with the display name.

Add—Opens the Add Server or URL dialog box, in which you can configure a new server or URL and display name.

Edit—Opens the Edit Server or URL dialog box, in which you can configure a new server or URL and display name.

Delete—Removes the selected item from the server and URL list. There is no confirmation or undo.

Move Up/Move Down—Changes the position of the selected item in the server and URL list.

Add/Edit Server or URL

The Add or Edit Server or URL dialog box lets you add or edit, delete, and order the items in the designated URL list.

Fields

•

URL Display Name—Specifies the URL name displayed to the user.

•



The Cisco AnyConnect VPN client provides secure SSL connections to the adaptive security appliance for remote users. The client gives remote users the benefits of an SSL VPN client without the need for network administrators to install and configure clients on remote computers.

Without a previously-installed client, remote users enter the IP address in their browser of an interface configured to accept SSL VPN connections. Unless the adaptive security appliance is configured to redirect http:// requests to https://, users must enter the URL in the form https://<

address

>.

After entering the URL, the browser connects to that interface and displays the login screen. If the user satisfies the login and authentication, and the adaptive security appliance identifies the user as requiring the client, it downloads the client that matches the operating system of the remote computer. After downloading, the client installs and configures itself, establishes a secure SSL connection and either remains or uninstalls itself (depending on the adaptive security appliance configuration) when the connection terminates.

In the case of a previously installed client, when the user authenticates, the adaptive security appliance examines the revision of the client, and upgrades the client as necessary.

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When the client negotiates an SSL VPN connection with the adaptive security appliance, it connects using Transport Layer Security (TLS), and optionally, Datagram Transport Layer Security (DTLS).

DTLS avoids latency and bandwidth problems associated with some SSL connections and improves the performance of real-time applications that are sensitive to packet delays.

The AnyConnect client can be downloaded from the adaptive security appliance, or it can be installed manually on the remote PC by the system administrator. For more information about installing the client manually, see the

Cisco AnyConnect VPN Client Release Notes

.

The adaptive security appliance downloads the client based on the group policy or username attributes of the user establishing the connection. You can configure the adaptive security appliance to automatically download the client, or you can configure it to prompt the remote user about whether to download the client. In the latter case, if the user does not respond, you can configure the adaptive security appliance to either download the client after a timeout period or present the login page.

Fields

•

Keep Installer on Client System—Enable to allow permanent client installation on the remote computer. Enabling disables the automatic uninstalling feature of the client. The client remains installed on the remote computer for subsequent connections, reducing the connection time for the remote user.

•

•

Compression—Compression increases the communications performance between the security appliance and the client by reducing the size of the packets being transferred.

Datagram TLS—Datagram Transport Layer Security avoids latency and bandwidth problems associated with some SSL connections and improves the performance of real-time applications that are sensitive to packet delays.

•

•

•

•

Ignore Don’t Defrag (DF) Bit—By default, the adaptive security appliance discards

SSL-encapsulated packets that exceed the SSL MTU. IPsec does not have an MTU, so an SSL session cannot, by default, encapsulate IPsec. If you want to support IPsec within an SSL session, enable this parameter to prevent the adaptive security appliance from discarding packets that exceed the SSL MTU. You must also enable the Ignore Routing and Filtering Rules parameter. An example use case is to let users establish an SSL VPN session with the adaptive security appliance and use that session to establish an IPsec VPN session with another enterprise. Without the initial SSL VPN session, network policies might prevent the establishment of the IPsec session from the endpoint.

Ignore Routing and Filtering Rules—By default, the group policy pushed to the SSL client permits client enforcement of routing and filtering rules configured on the endpoint. These rules can prevent the transmission of SSL-encapsulated packets containing IPsec-encapsulated packets. For example, the client may have a rule that prevents the exchange of SSL-encapsulated packets that exceed the

MTU size. If you want to support IPsec within an SSL session, enable this parameter to prevent the client from discarding packets that exceed the SSL MTU. You must also enable the Ignore Don’t

Defrag (DF) Bit parameter.

Keepalive Messages—Enter an number, from 15 to 600 seconds, in the Interval field to enable and adjust the interval of keepalive messages to ensure that an connection through a proxy, firewall, or

NAT device remains open, even if the device limits the time that the connection can be idle.

Adjusting the interval also ensures that the client does not disconnect and reconnect when the remote user is not actively running a socket-based application, such as Microsoft Outlook or Microsoft

Internet Explorer.

MTU—Adjusts the MTU size for SSL connections. Enter a value in bytes, from 256 to 1410 bytes.

By default, the MTU size is adjusted automatically based on the MTU of the interface that the connection uses, minus the IP/UDP/DTLS overhead.

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•

•

Optional Client Modules to Download

—To minimize download time, the AnyConnect client requests downloads (from the adaptive security appliance) only of modules that it needs for each feature that it supports. You must specify the names of modules that enable other features:

–

–

Enable the Start Before Logon (SBL) feature by checking

vpngina

. This enables the adaptive security appliance to download a graphical identification and authentication (GINA) for the

AnyConnect client VPN connection.

Enable the Cisco Diagnostic AnyConnect Reporting Tool (DART) by checking

dart

. DART captures a snapshot of system logs and other diagnostic information and creates a .zip file on your desktop so you can conveniently send troubleshooting information to Cisco TAC. For this keyword to have any effect, you must have installed the DART package on the adaptive security appliance.

Always-On VPN—Determine if the always-on VPN flag setting in the AnyConnect service profile is disabled or if the AnyConnect service profile setting should be used. The always-on VPN feature lets AnyConnect automatically establish a VPN session after the user logs onto a computer. The

VPN session remains up until the user logs off the computer. If the physical connection is lost, the session remains up, and AnyConnect continually attempts to reestablish the physical connection with the adaptive security appliance to resume the VPN session.

Always-on VPN permits the enforcement of corporate policies to protect the device from security threats. You can use it to help ensure AnyConnect establishes a VPN session whenever the endpoint is not in a trusted network. If enabled, a policy is configured to determine how network connectivity is managed in the absence of a connection.

Note

Always-On VPN requires an AnyConnect release that supports AnyConnect Secure

Mobility features. Refer to the

Cisco AnyConnect VPN Client Administrator Guide

for additional information.

•

Client Profiles to Download—A profile is a group of configuration parameters that the AnyConnect client uses to configure the connection entries that appear in the user interface, including the names and addresses of host computers. Choose

user

as the Profile type.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Using AnyConnect Client Profiles

The AnyConnect profile is an XML file deployed by the adaptive security appliance during client installation and updates. The profile provides basic information about connection setup, as well as advanced features such as Start Before Logon (SBL). Users cannot manage or modify profiles.

You can configure the adaptive security appliance to deploy profiles globally for all AnyConnect client users, or based on the group policy of the user. Usually, a user has a single profile file. This profile contains all the hosts needed by a user, and additional settings as needed. In some cases, you might want

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to provide more than one profile for a user. For example, someone who works from multiple locations might need more than one profile. In this case, the user selects the appropriate profile from a drop-down list. Be aware that some of the profile settings, such as Start Before Login, control the connection experience at a global level. Other settings, such as those unique to a particular host, depend on the host selected.

For more information about creating and deploying AnyConnect client profiles and controlling client features, see the

AnyConnect VPN Client Administrator Guide

.

Fields

Add

—Displays the Add SSL VPN Client Profiles dialog box, where you can specify a file in flash memory as a profile, or where you can browse flash memory for a file to specify as a profile. You can also upload a file from a local computer to the flash memory.

Edit

—Displays the Edit SSL VPN Client Profile window, where you can change the settings contained in the profile for AnyConnect client features.

Delete

—Deletes a profile from the table. This does not delete the XML file from flash.

Change Group Policy

—Launches a window where you can apply the profile to group policies from a list of all available group policies.

Import

—Displays a window where you can specify a file to import as an AnyConnect profile.

Export

—Displays a window where you can specify a path to export a profile, including a remote device or server.

SSL VPN Client Profiles Table

—Displays the XML files specified as SSL VPN client profiles:

•

Profile Name

—The name of the profile specified when the profile was added.

•

•

•

Profile Usage

—Displays the use for this profile.

Group Policy

—The group policy or policies this profile applies to.

Profile Location

—The path and filename of the XML file.

Adding an AnyConnect Client Profile

Add a new AnyConnect client profile in this window.



.

Fields

Profile Name

—Specify a name for the profile you add.

Profile Usage

—Specify VPN for the AnyConnect VPN client profile. Other selections are not supported. See the release notes for the AnyConnect VPN client for the latest information on supported features.

Group Policy

—Specify a group policy for this profile. The profile downloads to users belonging to the group policy along with the AnyConnect client.


—Specify a path to the profile file in the adaptive security appliance flash memory. If the file does not exist, the adaptive security appliance creates one based on the profile template.

Importing an AnyConnect Client Profile

Import a new AnyConnect client profile in this window. You can import a profile from a local device or a remote server.


64-42 OL-20339-01





.

Fields

Profile Name

—Specify a name for the profile you add.

Profile Usage

—This feature is not currently supported. See the release notes for the AnyConnect VPN client for the latest information on supported features.

Group Policy

—Specify a group policy for this profile. The profile downloads to users belonging to the group policy along with the AnyConnect client.


—Specify a path to the profile file in the adaptive security appliance flash memory. If the file does not exist, the adaptive security appliance creates one based on the profile template.

Exporting an AnyConnect Client Profile

Export an AnyConnect VPN client profile from this window. You can export to a local device or a remote server.



.

Fields

Device Profile Path

—Displays the path and filename of the profile file.

Local Path

—Specify the path and filename to export the profile file.

Browse Local

—Click to launch a window to browse the local device file system.

Exempting AnyConnect Traffic from Network Address Translation

If you have configured your ASA to perform network address translation (NAT), you must exempt your remote access AnyConnect client traffic from being translated so that the AnyConnect clients, internal networks, and corporate resources on a DMZ, can originate network connections to each other. Failing to exempt the AnyConnect client traffic from being translated prevents the AnyConnect clients and other corporate resources from communicating.

“Identity NAT” (also known as “NAT exemption”) allows an address to be translated to itself, which effectively bypasses NAT. Identity NAT can be applied between two address pools, an address pool and a subnetwork, or two subnetworks.

This procedure illustrates how you would configure identity NAT between these hypothetical network objects in our example network topology: Engineering VPN address pool, Sales VPN address pool, inside network, a DMZ network, and the Internet. Each Identity NAT configuration requires one NAT rule.

Table 64-1 Network Addressing for Configuring Identity NAT for VPN Clients

Network or Address Pool

Inside network

Network or address pool name Range of addresses

inside-network 10.50.50.0 - 10.50.50.255

Engineering VPN address pool Engineering-VPN

Sales VPN address pool

DMZ network

Sales-VPN

DMZ-network

10.60.60.1 - 10.60.60.254

10.70.70.1 - 10.70.70.254

192.168.1.0 - 192.168.1.255

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Step 1

Step 2

Log into the ASDM and select


.

Create a NAT rule so that the hosts in the Engineering VPN address pool can reach the hosts in the Sales

VPN address pool. In the NAT Rules pane, select

Add > Add NAT Rule Before “Network Object”

NAT rules

so that the ASA evaluates this rule before other rules in the Unified NAT table. See

Figure 64-2 on page 64-44 for an example of the Add NAT rule dialog box.

Note

In ASA software version 8.3, NAT rule evaluation is applied on a top-down, first match basis.

Once the ASA matches a packet to a particular NAT rule it does not perform any further evaluation. It is important that you place the most specific NAT rules at the top of the Unified

NAT table so that the ASA does not prematurely match them to broader NAT rules.

Figure 64-2 Add NAT rule dialog box

a.

In the

Match criteria: Original Packet

area, configure these fields:

–

Source Interface: Any

–

–

Destination Interface: Any

Source Address: Click the Source Address browse button and create the network object that represents the Engineering VPN address pool. Define the object type as a

Range

of addresses.

Do not add an automatic address translation rule. See

Figure 64-3

for an example.

–

Destination Address: Click the Destination Address browse button and create the network object that represents the Sales VPN address pool. Define the object type as a

Range

of addresses. Do not add an automatic address translation rule.

64-44


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Figure 64-3


Create Network Object for a VPN address pool

OL-20339-01

Step 3 b.

c.

In the

Action Translated Packet


–

Source NAT Type: Static

–

–

Source Address: Original

Destination Address: Original

–

Service: Original

In the

Options


–

–

Check

Enable rule

.

Uncheck or leave empty the


.

d.

e.

–

–

Direction: Both

Description: Add a Description for this rule.

Click

OK

.

Click

Apply

. Your rule should look like rule 1 in the

Unified NAT table in Figure 64-5 on page 64-48

.

CLI example:

nat source static Engineering-VPN Engineering-VPN destination static Sales-VPN

Sales-VPN

Click

Send

.

f.

When ASA is performing NAT, in order for two hosts in the same VPN pool to connect to each other, or for those hosts to reach the Internet through the VPN tunnel, you must enable the


option. To do this, in ASDM, select


. At the bottom of the Interface panel, check


and click

Apply

.

CLI example:

same-security-traffic permit inter-interface


64-45



Step 4

Step 5

Create a NAT rule so that the hosts in the Engineering VPN address pool can reach other hosts in the

Engineering VPN address pool. Create this rule just as you created the rule in

Step 2

except that you specify the Engineering VPN address pool as both the Source address and the Destination Address in the


area.

Create a NAT rule so that the Engineering VPN remote access clients can reach the “inside” network. In the NAT Rules pane, select

Add > Add NAT Rule Before “Network Object” NAT rules

so that this rule will be processed before other rules.

a.

In the


area configure these fields:

–

–


Destination Interface: Any

–

–

Source Address: Click the Source Address browse button and create a network object that represents the inside network. Define the object type as a

Network

of addresses. Do not add an automatic address translation rule.

Destination Address: Click the Destination Address browse button and select the network object that represents the Engineering VPN address pool.

Figure 64-4 Add inside-network object

b.

c.

In the

Action: Translated Packet


–

Source NAT Type: Static

–

–

Source Address: Original


–

Service: Original

In the

Options


–

–

Check

Enable rule

.



.

–

Direction: Both

64-46


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Step 6

Step 7 d.

e.

–


Click

OK

.

Click

Apply

. Your rule should look like rule two in the

Unified NAT table in Figure 64-5 on page 64-48

.

CLI example

nat source static inside-network inside-network destination static Engineering-VPN

Engineering-VPN

Create a new rule, following the method in

Step 5

, to configure identity NAT for the connection between the Engineering VPN address pool and the DMZ network. Use the DMZ network as the Source Address and use the Engineering VPN address pool as the Destination address.

Create a new NAT rule to allow the Engineering VPN address pool to access the Internet through the tunnel. In this case, you do not want to use identity NAT because you want to change the source address from a private address to an Internet routable address. To create this rule, follow this procedure:

a.

In the NAT Rules pane, select

Add > Add NAT Rule Before “Network Object” NAT rules

so that this rule will be processed before other rules.

b.

In the


area configure these fields:

–


–

–

Destination Interface: Any. This field will be automatically populated with “outside” after you select outside as the Source Address in the


area.

Source Address: Click the Source Address browse button and select the network object that represents the Engineering VPN address pool.

–

Destination Address: Any.

e.

f.

c.

d.

In the



–

Source NAT Type: Dynamic PAT (Hide)

–

–

Source Address: Click the Source Address browse button and select the


outside

interface.

–

Service: Original

In the

Options


–

–

Check

Enable rule

.



.

–

–

Direction: Both


Click

OK

.

Click

Apply

. Your rule should look like rule five in the

Unified NAT table

in


.

CLI example:

nat (any,outside) source dynamic Engineering-VPN interface

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64-47

Configuring SSL VPN Connections

Figure 64-5 Unified NAT table


Step 8

Step 9

After you have configured the Engineering VPN Address pool to reach itself, the Sales VPN address pool, the inside network, the DMZ network, and the Internet; you must repeat this process for the Sales

VPN address pool. Use identity NAT to exempt the Sales VPN address pool traffic from undergoing network address translation between itself, the inside network, the DMZ network, and the Internet.

From the

File

menu on the ASA, select

Save Running Configuration to Flash

to implement your identity NAT rules.


Use the AnyConnect Connection Profiles pane and its child dialog boxes to specify SSL VPN connection attributes for client-based connections. These attributes apply to the Cisco AnyConnect VPN client and to the legacy SSL VPN client.

The initial client deployment requires end-user administrative rights. The Cisco AnyConnect VPN client supports the HTTPS/TCP (SSL) and Datagram Transport Layer Security (DTLS) tunneling options.

In the main pane, you can enable client access on the interfaces you select and you can select, add, edit, and delete connections (tunnel groups). You can also specify whether you want to allow a user to select a particular connection at login.

Fields

•

Access Interfaces—Specify SSL VPN client access for each interface listed in the table:

–

Enable Cisco AnyConnect VPN Client or legacy SSL VPN Client access on the interfaces in the table below—Check this check box to enable the AnyConnect VPN client or the legacy SSL

VPN client on the interfaces listed in the Access Interfaces table.

–

–

Interface—The interface to enable SSL VPN client connections.

Allow Access—Check Allow Access to enable access on the interfaces listed in this table.

–

Enable DTLS—Check Enable DTLS to enable Datagram Transport Layer Security (DTLS) on an interface. DTLS avoids latency and bandwidth problems associated with some SSL connections and improves the performance of real-time applications that are sensitive to packet delays.

64-48


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•

•

–

Access Port—Specify the port for SSL VPN client connections. The default value is 443.

–

DTLS Port—Specify the port for DTLS connections. The default value is 443.

Login Page Setting—Allow the user to select a connection profile, identified by its alias, on the login page. If you do not check this check box, the default connection profile is DefaultWebVPNGroup.

Connection Profiles—Configure protocol-specific attributes for connections (tunnel groups).

–

Add/Edit—Click to Add or Edit a Connection Profile (tunnel group).

–

–

Name—The name of the Connection Profile.

Aliases—Other names by which the Connection Profile is known.

–

–

–

SSL VPN Client Protocol—Specifies whether SSL VPN client have access.

Group Policy—Shows the default group policy for this Connection Profile.

Allow user to select connection, identified by alias in the table above, at login page—Check to enable the display of Connection Profile (tunnel group) aliases on the Login page.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Setting the Basic Attributes for an SSL VPN Connection

To set the basic attributes for an SSL VPN connection, choose Add or Edit in the Connection Profiles section. The Add (or Edit) SSL VPN Connection > Basic dialog box opens.

Fields

Set the attributes in the Add SSL VPN Connection > Basic dialog box as follows:

•

Name—For Add, specify the name of the connection profile you are adding. For Edit, this field is not editable.

•

•

Aliases—(Optional) Enter one or more alternative names for the connection. You can spaces or punctuation to separate the names.

Authentication—Choose one of the following methods to use to authenticate the connection and specify a AAA server group to use in authentication.

–

–

AAA, Certificate, or Both—Select the type of authentication to use: AAA, Certificate, or Both.

If you choose either Certificate or Both, the user must provide a certificate in order to connect.

AAA Server Group—Choose a AAA server group from the drop-down list. The default setting is LOCAL, which specifies that the adaptive security appliance handles the authentication.

Before making a selection, you can click

Manage

to open a dialog box over this dialog box to view or make changes to the adaptive security appliance configuration of AAA server groups.

–

Choosing something other than LOCAL makes available the Use LOCAL if Server Group Fails check box.

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64-49



•

•

•

–

Use LOCAL if Server Group fails—Check to enable the use of the LOCAL database if the group specified by the Authentication Server Group attribute fails.

Client Address Assignment—Select the DHCP servers, client address pools, and client IPv6 address pools to use.

–

DHCP Servers—Enter the name or IP address of a DHCP server to use.

–

Client Address Pools—Enter the pool name of an available, configured pool of IP addresses to use for client address assignment. Before making a selection, you can click

Select

to open a dialog box over this dialog box to view or make changes to the address pools.

Default Group Policy—Select the group policy to use.

–

–

Group Policy—Select the VPN group policy that you want to assign as the default group policy for this connection. A VPN group policy is a collection of user-oriented attribute-value pairs that can be stored internally on the device or externally on a RADIUS server. The default value is DfltGrpPolicy. You can click

Manage

to open a dialog box over this one to make changes to the group policy configuration.

Enable SSL VPN Client Protocol—Check the check box to enable SSL VPN for this connection; uncheck to disable it.

Find—Enter a GUI label or a CLI command to use as a search string, then click Next or Previous to begin the search.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Setting Advanced Attributes for a Connection Profile

•

•

•

The Advanced menu items and their dialog boxes let you configure the following characteristics for this connection:

•

•

General attributes.

Client Addressing attributes

•

•

Authentication attributes.

Authorization attributes.

Accounting attributes.

Name server attributes.

Clientless SSL VPN attributes.

Note

SSL VPN and secondary authentication attributes apply only to SSL VPN connection profiles.

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Setting General Attributes for an AnyConnect SSL VPN Connection

Configure the General attributes to specify the password management parameters.

Fields

Set the Advanced General attributes as follows:

•

Enable Password Management—Lets you configure parameters relevant to overriding an account-disabled indication from a AAA server and to notifying users about password expiration.

The adaptive security appliance supports password management for the RADIUS and LDAP protocols. It supports the “password-expire-in-days” option only for LDAP. This parameter is valid for AAA servers that support such notification. The adaptive security appliance ignores this command if RADIUS or LDAP authentication has not been configured.

You can configure password management for IPsec remote access and SSL VPN tunnel-groups.

Note

Some RADIUS servers that support MS-CHAP currently do not support MS-CHAPv2. This feature requires MS-CHAPv2, so please check with your vendor.

The adaptive security appliance, releases 7.1 and later, generally supports password management for the following connection types when authenticating with LDAP or with any RADIUS configuration that supports MS-CHAPv2:

–

–

AnyConnect VPN client

IPsec VPN client

–

Clientless SSL VPN

Password management is

not

supported for any of these connection types for Kerberos/Active

Directory (Windows password) or NT 4.0 Domain. The RADIUS server (for example, Cisco ACS) could proxy the authentication request to another authentication server. However, from the adaptive security appliance perspective, it is talking only to a RADIUS server.

Note

For LDAP, the method to change a password is proprietary for the different LDAP servers on the market. Currently, the adaptive security appliance implements the proprietary password management logic only for Microsoft Active Directory and Sun LDAP servers.

Native LDAP requires an SSL connection. You must enable LDAP over SSL before attempting to do password management for LDAP. By default, LDAP uses port 636.

Note

Allowing override account-disabled is a potential security risk.

–

–

Notify user __ days prior to password expiration—Specifies that ASDM must notify the user at login a specific number of days before the password expires. The default is to notify the user 14 days prior to password expiration and every day thereafter until the user changes the password.

The range is 1 through 180 days.

Notify user on the day password expires—Notifies the user only on the day that the password expires.

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64-51



In either case, and, if the password expires without being changed, the adaptive security appliance offers the user the opportunity to change the password. If the current password has not expired, the user can still log in using that password.

Note

This does not change the number of days before the password expires, but rather, it enables the notification. If you select this option, you must also specify the number of days.

•

–

Override account-disabled indication from AAA server—Overrides an account-disabled indication from a AAA server.


Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Setting Client Addressing Attributes for an AnyConnect SSL VPN Connection

The Client Addressing attributes let you configure interface-specific address pools that your connection can use. Click Add to add a new address pool or Edit to modify an existing pool. The Select Address

Pools dialog box opens, showing a table listing the pool name, starting and ending address (or number of addresses), and subnet mask/prefix length of any existing pools. For a complete description of Client

Addressing see

Configuring Client Addressing, page 64-84

.

Configuring Authentication Attributes for an SSL VPN Connection Profile

•

•

Interface-specific Authentication Server Groups—Manages the assignment of authentication server groups to specific interfaces.

–

Add or Edit—Opens the Assign Authentication Server Group to Interface dialog box, in which you can specify the interface and server group, and specify whether to allow fallback to the

LOCAL database if the selected server group fails. The Manage button on this dialog box opens the Configure AAA Server Groups dialog box. Your selections appear in the Interface/Server

Group table.

–

Delete—Removes the selected server group from the table. There is no confirmation or undo.

Username Mapping from Certificate—Lets you specify the methods and fields in a digital certificate from which to extract the username.

–

–

Pre-fill Username from Certificate—Check to extract the names to be used for authentication from the primary and secondary fields specified in this panel. You must configure the authentication method for both AAA and certificates before checking this attribute. To do so, return to the Basic panel in the same window and check Both next to Method.

Hide username from end user—Specifies to not display the extracted username to the end user.


64-52 OL-20339-01



–

–

Specify the certificate fields to be used as the username—Specifies one or more fields to combine into the username.

Primary Field—Selects the first field to use from the certificate for the username. If this value is found, the secondary field is ignored.

Secondary Field—Selects the field to us if the primary field is not found. The possible values for the primary and secondary field attributes include the following:

N

O

I

L

DNQ

EA

GENQ

GN

Attribute

C

CN

OU

SER

SN

SP

T

UID

UPN

Definition

Country: the two-letter country abbreviation. These codes conform to ISO

3166 country abbreviations.

Common Name: the name of a person, system, or other entity. Not available a s a secondary attribute.

Domain Name Qualifier.

E-mail address.

Generational Qualifier.

Given Name.

Initials.

Locality: the city or town where the organization is located.

Name.

Organization: the name of the company, institution, agency, association or other entity.

Organizational Unit: the subgroup within the organization (O).

Serial Number.

Surname.

State/Province: the state or province where the organization is located

Title.

User Identifier.

User Principal Name.

–

–

–

–

Use the entire DN as the username—Uses the entire Distinguished Name field of the certificate as the username.

Use script to select username—Names the script from which to extract a username from the digital certificate. The default is --None--.

Add or Edit—Opens the Add or Edit Script Content dialog box, in which you can define a script to use in mapping the username from the certificate.

Delete—Deletes the selected script. There is no confirmation or undo.

Modes


Firewall Mode

Routed

•



—

•

Multiple

Context

—

System

—

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64-53



Configuring Secondary Authentication Attributes for an SSL VPN Connection

Profile

The Secondary Authentication dialog box lets you configure secondary or “double” authentication for this connection profile. With double authentication enabled, the end user must present two sets of valid authentication credentials in order to log on. You can use secondary authentication in conjunction with pre-filling the username from a certificate. The fields in this dialog box are similar to those you configure for primary authentication, but these fields relate only to secondary authentication.

When double authentication is enabled, these attributes select one or more fields in a certificate to use as the username. Configuring the secondary username from certificate attribute forces the security appliance to use the specified certificate field as the second username for the second username/password authentication.

Note

If you also specify the secondary authentication server group, along with the secondary username from certificate, only the primary username is used for authentication.

Fields

•

Secondary Authorization Server Group—Specifies an authorization server group from which to extract secondary credentials.

–

Server Group—Select an authorization server group to use as the secondary server AAA group.

The default is none. The secondary server group cannot be an SDI server group.

•

–

–

Manage—Opens the Configure AAA Server Groups dialog box.

Use LOCAL if Server Group fails—Specifies to fall back to the LOCAL database if the specified server group fails.

Use primary username—Specifies that the login dialog must request only one username.

–

Attributes Server—Select whether this is the primary or secondary attributes server.

Note

If you also specify an authorization server for this connection profile, the authorization server settings take precedence—the adaptive security appliance ignores this secondary authentication server.

•

•

–

Session Username Server—Select whether this is the primary or secondary session username server.

Interface-specific Authorization Server Groups—Manages the assignment of authorization server groups to specific interfaces.

–



Group table.

–


Username Mapping from Certificate—Specify the fields in a digital certificate from which to extract the username.

64-54


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•

•

•

•

Pre-fill Username from Certificate—Check to extract the names to be used for secondary authentication from the primary and secondary fields specified in this panel. You must configure the authentication method for both AAA and certificates before checking this attribute. To do so, return to the Basic panel in the same window and check Both next to Method.

Hide username from end user—Check to hide the username to be used for authentication from the

VPN user.

Password—Choose one of the following methods to retrieve the password to be used for authentication:

–

–

Prompt—Prompt the user for the password.

Use Primary—Reuse the primary authentication password for all secondary authentications.

–

Use—Enter a common secondary password for all secondary authentications.

Specify the certificate fields to be used as the username—Specifies one or more fields to match as the username. To use this username in the pre-fill username from certificate feature for the secondary username/password authentication or authorization, you must also configure the pre-fill-username and secondary-pre-fill-username.

–

–

Primary Field—Selects the first field to use from the certificate for the username. If this value is found, the secondary field is ignored.

Secondary Field—Selects the field to us if the primary field is not found.

The options for primary and secondary field attributes include the following:

Attribute

C

CN

L

N

O

DNQ

EA

GENQ

GN

I

OU

SER

SN

SP

T

UID

UPN

Definition

Country: the two-letter country abbreviation. These codes conform to ISO

3166 country abbreviations.

Common Name: the name of a person, system, or other entity. Not available a s a secondary attribute.

Domain Name Qualifier.

E-mail address.

Generational Qualifier.

Given Name.

Initials.

Locality: the city or town where the organization is located.

Name.

Organization: the name of the company, institution, agency, association or other entity.

Organizational Unit: the subgroup within the organization (O).

Serial Number.

Surname.

State/Province: the state or province where the organization is located

Title.

User Identifier.

User Principal Name.

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64-55



•

•

Use the entire DN as the username—Uses the entire subject DN (RFC1779) to derive a name for an authorization query from a digital certificate.

Use script to select username—Names the script from which to extract a username from a digital certificate. The default is --None--.

–


–


Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Configuring Authorization Attributes for an SSL VPN Connection Profile

The Authorization dialog box lets you view, add, edit, or delete interface-specific authorization server groups. Each row of the table on this dialog box shows the status of one interface-specific server group: the interface name, its associated server group, and whether fallback to the local database is enabled if the selected server group fails.

Fields

•

Authorization Server Group—Specifies an authorization server group from which to draw authorization parameters.

–

Server Group—Selects an authorization server group to use. The default is none.

•

–

–


Users must exist in the authorization database to connect—Select this check box to require that users meet this criterion.


–



Group table.

•

–


Username Mapping from Certificate—Specify the fields in a digital certificate from which to extract the username.

–

–



64-56


OL-20339-01



•

–

–

–


Use the entire DN as the username—Specifies that you want to use the entire Distinguished

Name field of the certificate as the username.

Specify the certificate fields to be used as the username—Specifies one or more fields to combine into the username.

–

–

Primary Field—Selects the first field to use in the certificate for the username. If this value is found, the secondary field is ignored.

Secondary Field—Selects the field to use if the primary field is not found.


Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Adding or Editing Content to a Script for Certificate Pre-Fill-Username

The Add or Edit Script Content dialog box lets you create an authentication or authorization script.

Note

Both AnyConnect client and clientless WebVPN display “Unknown” in the username field when pre-fill-username from certificate using a script cannot find the username in the client certificate.

Fields

•

Script Name—Specify the name of the script. The script name must be the same in both authorization and authentication.You define the script here, and CLI uses the same script to perform this function.

•

•

Select script parameters—Specify the attributes and content of the script.

•

•

Value for Username—Select an attribute from the drop-down list of standard DN attributes to use as the username (Subject DN).

No Filtering—Specify that you want to use the entire specified DN name.

Filter by substring— Specify the Starting Index (the position in the string of the first character to match) and Ending Index (number of characters to search). If you choose this option, the starting index cannot be blank. If you leave the ending index blank, it defaults to -1, indicating that the entire string is searched for a match.

For example, suppose you selected the DN attribute Common Name (CN), which contains a value of host/user. Table 64-1 shows some possible ways you might filter this value using the substring option to achieve various return values. The Return Value is what is actually pre-filled as the username.

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64-57



Table 64-2

Starting Index Ending Index

1

6

6

Filtering by Substring

5

10

-1

Return Value

host/ user user

•

•

Using a negative index, as in the third row of this table, specifies to count from the end of the string backwards to the end of the substring, in this case, the “r” of “user”.

When using filtering by substrings, you should know the length of the substring that you are seeking.

From the following examples, use either the regular expression matching or the custom script in Lua format:

Example 1: Regular Expression Matching—Enter a regular expression to apply to the search in the

Regular Expression field. Standard regular expression operators apply. For example, suppose you want to use a regular expression to filter everything up to the @ symbol of the "Email Address (EA)"

DN value. The regular expression ^[^@]* would be one way to do this. In this example, if the DN value contained a value of [email protected], the return value after the regular expression would be user1234.

Example 2: Use custom script in Lua format—Specify a custom script written in the Lua programming language to parse the search fields. Selecting this option makes available a field in which you can enter your custom Lua script; for example, the script: return cert.subject.cn..'/'..cert.subject.l combines two DN fields, username (cn) and locality (l), to use as a single username and inserts the slash (/) character between the two fields.

Table 64-3 lists the attribute names and descriptions that you can use in a Lua script.

Note

Lua is case-sensitive.

Table 64-3 Attribute Names and Descriptions

Attribute Name

cert.subject.c

cert.subject.cn

cert.subject.dnq

cert.subject.ea

cert.subject.genq

cert.subject.gn

cert.subject.i

cert.subject.l

cert.subject.n

cert.subject.o

cert.subject.ou

Description

Country

Common Name

DN qualifier

Email Address

Generational qualified

Given Name

Initials

Locality

Name

Organization

Organization Unit

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Table 64-3 Attribute Names and Descriptions

cert.subject.ser

cert.subject.sn

cert.subject.sp

cert.subject.t

cert.subject.uid

cert.issuer.c

cert.issuer.cn

cert.issuer.dnq

cert.issuer.ea

cert.issuer.genq

cert.issuer.gn

cert.issuer.i

cert.issuer.l

cert.issuer.n

cert.issuer.o

cert.issuer.ou

cert.issuer.ser

cert.issuer.sn

cert.issuer.sp

cert.issuer.t

cert.issuer.uid

cert.serialnumber

cert.subjectaltname.upn

Subject Serial Number

Surname

State/Province

Title

User ID

Country

Common Name

DN qualifier

Email Address

Generational qualified

Given Name

Initials

Locality

Name

Organization

Organization Unit

Issuer Serial Number

Surname

State/Province

Title

User ID

Certificate Serial Number

User Principal Name

If an error occurs while activating a tunnel group script, causing the script not to activate, the administrator’s console displays an error message.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

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64-59


Configuring AnyConnect Secure Mobility

Configuring AnyConnect Secure Mobility

AnyConnect Secure Mobility protects corporate interests and assets from Internet threats when employees are mobile. Use the Mobile User Security dialog box to configure this feature. AnyConnect

Secure Mobility lets Cisco IronPort S-Series Web Security appliances scan Cisco AnyConnect secure mobility clients to ensure that clients are protected from malicious software and/or inappropriate sites.

The client periodically checks to ensure that Cisco IronPort S-Series Web Security appliance protection is enabled.

To configure secure mobility solutions, choose

Configuration > Remote Access VPN > Network

(Client) Access > Mobile User Security

.

Note

This feature requires a release of the Cisco IronPort Web Security appliance that provides

AnyConnect Secure Mobility licensing support for the Cisco AnyConnect secure mobility client.

It also requires an AnyConnect release that supports the AnyConnect Secure Mobility feature.

Figure 64-6 Mobile User Security Window

Fields

•

Service Access Control—Specifies from which host or network address the WSAs can communicate.

–

–

Add—Opens the Add MUS Access Control Configuration dialog box for the selected connection.

Edit—Opens the Edit MUS Access Control Configuration dialog box for the selected connection.

•

–

Delete—Removes the selected connection from the table. There is no confirmation or undo.

Enable Mobile User Security Service—Starts the connection with the client through the VPN. If enabled, you are required to enter a password, used by the WSA when contacting the ASA. If no

WSA is present, the status is disabled.

64-60


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Configuring Clientless SSL VPN Connections

•

•

•

•

•

Service Port—If you choose to enable the service, specify which port number for the service to use.

The port must be between 1 and 65535 and must match the corresponding value provisioned into the

WSA with the management system. The default is 11999.

Change Password—Enables you to change the WSA access password.

WSA Access Password—Specify the shared secret password required for authentication between the ASA and WSA. This password must match the corresponding password provisioned into the

WSA with the management system.

Confirm Password—Re-enter the specified password.

Show WSA Sessions—Allows you to view session information of WSAs connected to the ASA.The host IP address of the WSA that is connected (or has been connected) and the duration of the connection is returned in a dialog box.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add or Edit MUS Access Control

The Add or Edit MUS Access Control dialog box lets you configure MUS access.

Fields

•

•

Interface Name—Use the drop-down menu to choose which interface name you are adding or editing.

IP Address—Enter either an IPv4 or IPv6 address.

•

Mask—Use the drop-down menu to choose the appropriate mask.


Use the Clientless SSL VPN Access Connections dialog box to configure clientless SSL VPN access parameters. This dialog box also records the configuration choices you make in its child dialog boxes.

Fields

•

Access Interfaces—Lets you select from a table the interfaces on which to enable access. The fields in this table include the interface name and check boxes enabling you whether to allow access and require a certificate for authentication.

•

Access Port—Specifies the access port for the connection. The default value is 443.

•

Connections—Provides a connection table that shows the records that determine the connection policy for this connection (tunnel group). Each record identifies a default group policy for the connection and contains protocol-specific connection parameters.

–

Add—Opens the Add Clientless SSL VPN dialog box for the selected connection.

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64-61



–

Edit—Opens the Edit Clientless SSL VPN dialog box for the selected connection.

–

–

Delete—Removes the selected connection from the table. There is no confirmation or undo.

Allow user to select connection, identified by alias in the table above, at login page—Specifies that the user login page presents the user with a drop-down menu from which the user can select a particular tunnel group with which to connect.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add or Edit Clientless SSL VPN Connections

The Add or Edit SSL VPN dialog box consists of Basic and Advanced sections, accessible through the expandable menu on the left of the box.

Add or Edit Clientless SSL VPN Connections > Basic

The Basic dialog box lets you configure essential characteristics for this connection.

Fields

•

Name—Specifies the name of the connection. For the edit function, this field is read-only.

•

Aliases—(Optional) Specifies one or more alternate names for this connection. The aliases appear on the login page if you configure that option on the Clientless SSL VPN Access Connections dialog box.

•

Authentication—Specifies the authentication parameters.

–

Method—Specifies whether to use AAA authentication, certificate authentication, or both methods for this connection. The default is AAA authentication.

–

–

AAA server Group—Selects the AAA server group to use for authenticating this connection.

The default is LOCAL.


•

•

DNS Server Group—Selects the server to use as the DNS server group for this connection. The default is DefaultDNS.

Default Group Policy—Specifies the default group policy parameters to use for this connection.

–

–

Group Policy—Selects the default group policy to use for this connection. The default is

DfltGrpPolicy.

Clientless SSL VPN Protocol—Enables or disables the Clientless SSL VPN protocol for this connection.

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Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add or Edit Clientless SSL VPN Connections > Advanced

•

•

•

The Advanced menu items and their dialog boxes let you configure the following characteristics for this connection:

•

•

General attributes.

Authentication attributes.

•

Authorization attributes.

Accounting attributes.

Name server attributes.

Clientless SSL VPN attributes.

Add or Edit Clientless SSL VPN Connections > Advanced > General

Use this dialog box to specify whether to strip the realm and group from the username before passing them to the AAA server, and to specify password management options.

Fields

•

Password Management—Lets you configure parameters relevant to overriding an account-disabled indication from a AAA server and to notifying users about password expiration.

–

Enable notification password management—Checking this check box makes the following two parameters available. You can select either to notify the user at login a specific number of days before the password expires or to notify the user only on the day that the password expires. The default is to notify the user 14 days prior to password expiration and every day thereafter until the user changes the password. The range is 1 through 180 days.

Note


In either case, and, if the password expires without being changed, the adaptive security appliance offers the user the opportunity to change the password. If the current password has not yet expired, the user can still log in using that password.

This parameter is valid for AAA servers that support such notification; that is, RADIUS,

RADIUS with an NT server, and LDAP servers. The adaptive security appliance ignores this command if RADIUS or LDAP authentication has not been configured.

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–


Note


Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add or Edit Clientless or SSL VPN Client Connection Profile or IPsec Connection

Profiles> Advanced > Authentication

The Authentication dialog box lets you view, add, edit, or delete interface-specific authentication server groups. Each row of the table on this dialog box shows the status of one interface-specific server group: the interface name, its associated server group, and whether fallback to the local database is enabled if the selected server group fails.

Fields

•


–

–



Group table.


Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Assign Authentication Server Group to Interface

This dialog box lets you associate an interface with a AAA server group. The results appear in the table on the Authentication dialog box.

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Fields

•

Interface—Selects an interface, DMZ, Outside, or Inside. The default is DMZ.

•

Server Group—Selects a server group to assign to the selected interface. The default is LOCAL.

•

•


Fallback—Enables or disables fallback to LOCAL if the selected server group fails.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add or Edit SSL VPN Connections > Advanced > Authorization

This dialog box lets you configure the default authorization server group, interface-specific authorization server groups, and user name mapping attributes. The attributes are the same for SSL VPN and Clientless SSL VPN connections.

Fields

•

Default Authorization Server Group—Configures default authorization server group attributes.

–

–

Server Group—Selects the authorization server group to use for this connection. The default is

--None--.


•

–

Users must exist in the authorization database to connect—Enables or disables this requirement.

Interface-specific Authorization Server Groups

–

–

Table—Lists each configured interface and the server group with which it is associated.

Add or Edit—Opens the Assign Authorization Server Group to Interface dialog box.

•

•

–

Delete—Removes the selected row from the table.

User Name Mapping—Specifies user name mapping attributes.

Username Mapping from Certificate—Lets you specify the fields in a digital certificate from which to extract the username.

–

Pre-fill Username from Certificate—Check to extract the names to be used for secondary authentication from the primary and secondary fields specified in this panel. You must configure the authentication method for both AAA and certificates before checking this attribute.

–

–

–

–

Hide username from end user—Specifies not to display the extracted username to the end user.




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–

Use the entire DN as the username—Enables or disables the requirement to use the entire DN as the username.

–

–

Specify individual DN fields as the username. You can select both the primary DN field, for which the default is CN (Common Name) and the secondary DN field, for which the default is

OU (Organization Unit).

Primary Field—Selects the first field to use in the username.

–

Secondary Field—Selects the second field to use in the username.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Assign Authorization Server Group to Interface

This dialog box lets you associate an interface with a AAA server group. The results appear in the table on the Authorization dialog box.

Fields

•

Interface—Selects an interface, DMZ, Outside, or Inside. The default is DMZ.

•

Server Group—Selects a server group to assign to the selected interface. The default is LOCAL.

•


Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add or Edit SSL VPN Connections > Advanced > SSL VPN

This dialog box lets you configure attributes that affect what the remote user sees upon login.

Fields

•

Portal Page Customization—Configures the look and feel of the user login page by specifying which preconfigured customization attributes to apply. The default is DfltCustomization.

•

Enable the display of Radius Reject-Message on the login screen—Select this check box to display the RADIUS-reject message on the login dialog box when authentication is rejected.

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•

•

•

•

•

Enable the display of SecurId message on the login screen—Select this check box to display

SecurID messages on the login dialog box.

Manage—Opens the Configure GUI Customization Objects dialog box.

Connection Aliases—Lists in a table the existing connection aliases and their status and lets you add or delete items in that table. A connection alias appears on the user login page if the connection is configured to allow users to select a particular connection (tunnel group) at login. The rows in this table are editable in place, so there is no Edit button. Clicking the “i” icon above the table opens a tooltip for the edit function.

–

–

Add—Opens the Add Connection Alias dialog box, on which you can add and enable a connection alias.

Delete—Removes the selected row from the connection alias table. There is no confirmation or undo.

–

To edit an alias listed in the table, double-click the line.

Group URLs—Lists in a table the existing group URLs and their status and lets you add or delete items in that table. A group URL appears on the user login page if the connection is configured to allow users to select a particular group at login. The rows in this table are editable in place, so there is no Edit button. Clicking the “i” icon above the table opens a tooltip for the edit function.

–

–

Add—Opens the Add Group URL dialog box, on which you can add and enable a group URL.


–

To edit a URL listed in the table, double-click the line.

Do not run Cisco Secure Desktop (CSD) on client machine when using group URLs defined above to access the ASA. (If a client connects using a connection alias, this setting is ignored.)—Check if you want to exempt users from running CSD who use a URL that matches an entry in the Group URLs table.

Be aware that doing so stops the security appliance from receiving endpoint criteria from these users, so you might have to change the DAP configuration to provide them with VPN access.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add or Edit Clientless SSL VPN Connections > Advanced > Clientless SSL VPN

This dialog box lets you configure attributes that affect what the remote user sees upon login.

Fields

•

Portal Page Customization—Configures the look and feel of the user login page by specifying which preconfigured customization attributes to apply. The default is DfltCustomization.

•

Enable the display of Radius Reject-Message on the login screen—Select this check box to display the RADIUS-reject message on the login dialog box when authentication is rejected.

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•

•

•

•

•

Enable the display of SecurId message on the login screen—Select this check box to display

SecurID messages on the login dialog box.


Connection Aliases—Lists in a table the existing connection aliases and their status and lets you add or delete items in that table. A connection alias appears on the user login page if the connection is configured to allow users to select a particular connection (tunnel group) at login.

–

–

Add—Opens the Add Connection Alias dialog box, on which you can add and enable a connection alias.


Group URLs—Lists in a table the existing group URLs and their status and lets you add or delete items in that table. A group URL appears on the user login page if the connection is configured to allow users to select a particular group at login.

–

Add—Opens the Add Group URL dialog box, on which you can add and enable a group URL.

–


Do not run Cisco Secure Desktop (CSD) on client machine when using group URLs defined above to access the ASA. (If a client connects using a connection alias, this setting is ignored.)—Check if you want to exempt users from running CSD who use a URL that matches an entry in the Group URLs table.

Be aware that doing so stops the security appliance from receiving endpoint criteria from these users, so you might have to change the DAP configuration to provide them with VPN access.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add or Edit Clientless SSL VPN Connections > Advanced > NetBIOS Servers

The table on this dialog box shows the attributes of the already-configured NetBIOS servers. The Add or Edit Tunnel Group dialog box for Clientless SSL VPN access, NetBIOS dialog box, lets you configure the NetBIOS attributes for the tunnel group. Clientless SSL VPN uses NetBIOS and the Common

Internet File System protocol to access or share files on remote systems. When you attempt a file-sharing connection to a Windows computer by using its computer name, the file server you specify corresponds to a specific NetBIOS name that identifies a resource on the network.

The adaptive security appliance queries NetBIOS name servers to map NetBIOS names to IP addresses.

Clientless SSL VPN requires NetBIOS to access or share files on remote systems.

To make the NBNS function operational, you must configure at least one NetBIOS server (host). You can configure up to 3 NBNS servers for redundancy. The adaptive security appliance uses the first server on the list for NetBIOS/CIFS name resolution. If the query fails, it uses the next server.

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Fields

•

IP Address—Displays the IP addresses of configured NetBIOS servers.

•

Master Browser—Shows whether a server is a WINS server or one that can also be a CIFS server

(that is, a master browser).

•

•

Timeout (seconds)—Displays the initial time in seconds that the server waits for a response to an

NBNS query before sending the query to the next server.

Retries—Shows the number of times to retry sending an NBNS query to the configured servers, in order. In other words, this is the number of times to cycle through the list of servers before returning an error. The minimum number of retries is 0. The default number of retries is 2. The maximum number of retries is 10.

•

•

•

Add/Edit—Click to add a NetBIOS server. This opens the Add or Edit NetBIOS Server dialog box.

Delete—Removes the highlighted NetBIOS row from the list.

Move Up/Move Down—The adaptive security appliance sends NBNS queries to the NetBIOS servers in the order in which they appear in this box. Use this box to change the priority order of the servers by moving them up or down in the list.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Configure DNS Server Groups

This dialog box displays the configured DNS servers in a table, including the server group name, servers, timeout in seconds, number of retries allowed, and domain name. You can add, edit, or delete DNS server groups on this dialog box.

Fields

•

Add or Edit—Opens the Add or Edit DNS Server Group dialog box.

•

Delete—Removes the selected row from the table. There is no confirmation or undo.

•

•

DNS Server Group—Selects the server to use as the DNS server group for this connection. The default is DefaultDNS.

Manage—Opens the Configure DNS Server Groups dialog box.

Modes


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IPsec Remote Access Connection Profiles

Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add or Edit Clientless SSL VPN Connections > Advanced > Clientless SSL VPN

This dialog box lets you specify portal-related attributes for Clientless SSL VPN connections.

Fields

•

Portal Page Customization—Selects the customization to apply to the user interface.

•


Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

IPsec Remote Access Connection Profiles

The parameters in the IPsec Connection Profiles dialog box let you configure IPsec remote access connections. Most of the parameters in this section were formerly configured under tunnel groups. An

IPsec connection represents a connection-specific record for IPsec and Clientless SSL VPN connections.

The IPsec group uses the IPsec connection parameters to create a tunnel. An IPsec connection can be either remote-access or Site-to-Site. The IPsec group is configured on the internal server or on an external RADIUS server. For ASA 5505 in client mode or VPN 3002 hardware client parameters, which enable or disable interactive hardware client authentication and individual user authentication, the IPsec connection parameters take precedence over parameters set for users and groups.

The Clientless SSL VPN tunnel-group parameters are the parameters of the Clientless SSL VPN group that you want to apply to this IPsec connection. You configure Clientless SSL VPN access on the

Configuration > Clientless SSL VPN dialog box.

Fields

•

Access Interfaces—Selects the interfaces to enable for IPsec access. The default is that no access is selected.

•

Connections—Shows in tabular format the configured parameters for existing IPsec connections.

The Connections table contains records that determine connection policies. A record identifies a default group policy for the connection and contains protocol-specific connection parameters. The table contains the following columns:

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Add or Edit an IPsec Remote Access Connection Profile

•

•

–

–

–

Name—Specifies the name or IP address of the IPsec connection.

ID Certificate—Specifies the name of the ID certificate, if available.

IPsec Protocol—Indicates whether the IPsec protocol is enabled. You enable this protocol on the Add or Edit IPsec Remote Access Connection, Basic dialog box.

–

–

L2TP/IPsec Protocol—Indicates whether the L2TP/IPsec protocol is enabled. You enable this protocol on the Add or Edit IPsec Remote Access Connection, Basic dialog box.

Group Policy—Indicates the name of the group policy for this IPsec connection.

Add or Edit—Opens the Add or Edit IPsec Remote Access Connection Profile dialog box.


Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add or Edit an IPsec Remote Access Connection Profile

The Add or Edit IPsec Remote Access Connection Profile dialog box has a navigation pane that lets you select basic or advanced elements to configure.

Add or Edit IPsec Remote Access Connection Profile Basic

The Add or Edit IPsec Remote Access Connection Profile Basic dialog box lets you configure common attributes for IPsec connections.

Fields

•

Name—Identifies the name of the connection.

•

IKE Peer Authentication—Configures IKE peers.

–

Pre-shared key—Specifies the value of the pre-shared key for the connection. The maximum length of a pre-shared key is 128 characters.

•

–

–

Identity Certificate—Selects the name of an identity certificate, if any identity certificates are configured and enrolled.

Manage—Opens the Manage Identity Certificates dialog box, on which you can add, edit, delete, export, and show details for a selected certificate.

User Authentication—Specifies information about the servers used for user authentication. You can configure more authentication information in the Advanced section.

–

Server Group—Selects the server group to use for user authentication. the default is LOCAL.

If you select something other than LOCAL, the Fallback check box becomes available.

–


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Mapping Certificates to IPsec or SSL VPN Connection Profiles

•

•

–

Fallback—Specifies whether to use LOCAL for user authentication if the specified server group fails.

Client Address Assignment—Specifies attributes relevant to assigning client attributes.

–

DHCP Servers—Specifies the IP address of a DHCP server to use. You can add up to 10 servers, separated by spaces.

–

–

Client Address Pools—Specifies up to 6 predefined address pools. To define an address pool, go to Configuration > Remote Access VPN > Network Client Access > Address Assignment >

Address Pools.

Select—Opens the Select Address Pools dialog box.

Default Group Policy—Specifies attributes relevant to the default group policy.

–

Group Policy—Selects the default group policy to use for this connection. The default is

DfltGrpPolicy.

–

–

Manage—Opens the Configure Group Policies dialog box, from which you can add, edit, or delete group policies.

Client Protocols—Selects the protocol or protocols to use for this connection. By default, both

IPsec and L2TP over IPsec are selected.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—


When the adaptive security appliance receives an IPsec connection request with client certificate authentication, it assigns a connection profile to the connection according to policies you configure. That policy can be to use rules you configure, use the certificate OU field, use the IKE identity (i.e. hostname,

IP address, key ID), the peer IP address, or a default connection profile. For SSL connections, the adaptive security appliance only uses the rules you configure.

For IPsec or SSL connections using rules, the adaptive security appliance evaluates the attributes of the certificate against the rules until it finds a match. When it finds a match, it assigns the connection profile associated with the matched rule to the connection. If it fails to find a match, it assigns the default connection profile (DefaultRAGroup for IPsec and DefaultWEBVPNGroup for SSL VPN) to the connection and lets the user choose the connection profile from a drop-down menu displayed on the portal page (if it is enabled). The outcome of the connection attempt once in this connection profile depends on whether or not the certificate is valid and the authentication settings of the connection profile.

A certificate group matching policy defines the method to use for identifying the permission groups of certificate users. You can use any or all of these methods.

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First configure the policy for matching a certificate to a connection profile at Configuration > Remote

Access VPN > Network (Client) Access > Advanced > IPSec > Certificate to Connection Profile Maps.

If you choose to use rules you configure, go to Rules to specify the rules. The following procedures shows how you create the certificate-based criteria for each IPsec and SSL VPN connection profile:

Step 1

Step 2

Use the table at the top (Certificate to Connection Profile Maps) to do one of the following:

•

Create a list name, called a “map,” specify the priority of the list, and assign the list to a connection profile.

ASDM highlights the list after you add it to the table.

•

Confirm that a list is assigned to the connection profile for which you want to add certificate-based rules.

ASDM highlights the list after you add it to the table and displays any associated list entries in the table at the bottom of the pane.

Use the table at the bottom (Mapping Criteria) to view, add, change or delete entries to the selected list.

Each entry in the list consists of one certificate-based rule. All of the rules in the mapping criteria list need to match the contents of the certificate for the adaptive security appliance to choose the associated map index. To assign a connection if one criterion or another matches, create one list for each matching criterion.

To understand the fields, see the following sections:

•

•

•

Setting a Certificate Matching Policy

Add/Edit Certificate Matching Rule

Add/Edit Certificate Matching Rule Criterion

Setting a Certificate Matching Policy

For IPsec connections, a certificate group matching policy defines the method to use for identifying the permission groups of certificate users. You can use any or all of these methods:

Fields

•

Use the configured rules to match a certificate to a group—Lets you use the rules you have defined under Rules.

•

•

Use the certificate OU field to determine the group—Lets you use the organizational unit field to determine the group to which to match the certificate. This is selected by default.

Use the IKE identity to determine the group—Lets you use the identity you previously defined under

Configuration > VPN > IKE > Global Parameters. The IKE identity can be hostname, IP address, key ID, or automatic.

•

•

Use the peer IP address to determine the group—Lets you use the peer's IP address. This is selected by default.

Default to group—Lets you select a default group for certificate users that is used when none of the preceding methods resulted in a match. This is selected by default. Click the default group in the

Default to group list. The group must already exist in the configuration. If the group does not appear in the list, you must define it by using Configuration > VPN > General > Tunnel Group.

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Add/Edit Certificate Matching Rule

Use the

Add/Edit Certificate Matching Rule

dialog box to assign the name of a list (map) to a connection profile.

Fields

• Map

—Choose one of the following:

–

Existing

—Select the name of the map to include the rule.

•

– New

—Enter a new map name for a rule.

Rule Priority

—Type a decimal to specify the sequence with which the adaptive security appliance evaluates the map when it receives a connection request. For the first rule defined, the default priority is 10. The adaptive security appliance evaluates each connection against the map with the lowest priority number first.

• Mapped to Connection Profile

—Select the connection profile, formerly called a “tunnel group,” to map to this rule.

If you do not assign a rule criterion to the map, as described in the next section, the adaptive security appliance ignores the map entry.

Modes


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Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit Certificate Matching Rule Criterion

Use the

Add/Edit Certificate Matching Rule Criterion

dialog box to configure a certificate matching rule criterion for the selected connection profile.

Fields

•

Rule Priority

—(Display only). Sequence with which the adaptive security appliance evaluates the map when it receives a connection request. The adaptive security appliance evaluates each connection against the map with the lowest priority number first.

•

•

Mapped to Group

—(Display only). Connection profile to which the rule is assigned.

Field

—Select the part of the certificate to be evaluated from the drop-down list.

•

–

–

–

–

Subject

—The person or system that uses the certificate. For a CA root certificate, the Subject and Issuer are the same.

Alternative Subject

—The subject alternative names extension allows additional identities to be bound to the subject of the certificate.

Issuer

—The CA or other entity (jurisdiction) that issued the certificate.

Extended Key Usage

—An extension of the client certificate that provides further criteria that you can choose to match.

Component

—(Applies only if Subject of Issuer is selected.) Select the distinguished name component used in the rule:

DN Field

Whole Field

Definition

The entire DN.

Country (C)

The two-letter country abbreviation. These codes conform to ISO 3166 country abbreviations.

Common Name (CN)

The name of a person, system, or other entity. This is the lowest (most specific) level in the identification hierarchy.

DN Qualifier (DNQ)

A specific DN attribute.

E-mail Address (EA)

The e-mail address of the person, system or entity that owns the certificate.

Generational Qualifier

(GENQ)

Given Name (GN)

Initials (I)

Locality (L)

A generational qualifier such as Jr., Sr., or III.

The first name of the certificate owner.

The first letters of each part of the certificate owner’s name.

Name (N)

Organization (O)

The city or town where the organization is located.

The name of the certificate owner.

The name of the company, institution, agency, association, or other entity.

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DN Field

Organizational Unit

(OU)

Definition

The subgroup within the organization.

Serial Number (SER)

The serial number of the certificate.

Surname (SN)

The family name or last name of the certificate owner.

State/Province (S/P)

Title (T)

The state or province where the organization is located.

The title of the certificate owner, such as Dr.

User ID (UID)

Unstructured Name

(UNAME)

IP Address (IP)

The identification number of the certificate owner.

The unstructuredName attribute type specifies the name or names of a subject as an unstructured ASCII string.

IP address field.

•

•

Operator

—Select the operator used in the rule:

–

Equals

—The distinguished name field must exactly match the value.

–

–

Contains

—The distinguished name field must include the value within it.

Does Not Equal

—The distinguished name field must not match the value

– Does Not Contain

—The distinguished name field must not include the value within it.

Value

—Enter up to 255 characters to specify the object of the operator. For Extended Key Usage, select one of the pre-defined values in the drop-down list, or you can enter OIDs for other extensions. The pre-defined values include the following:

Selection

clientauth codesigning emailprotection ocspsigning serverauth timestamping

Key Usage Purpose


Code Signing

Secure Email Protection

OCSP Signing

Server Authentication

Time Stamping

OID String

1.3.6.1.5.5.7.3.2

1.3.6.1.5.5.7.3.3

1.3.6.1.5.5.7.3.4

1.3.6.1.5.5.7.3.9

1.3.6.1.5.5.7.3.1

1.3.6.1.5.5.7.3.8

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

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Site-to-Site Connection Profiles

The Connection Profiles dialog box shows the attributes of the currently configured Site-to-Site connection profiles (tunnel groups), lets you select the delimiter to use when parsing connection profile names, and lets you add, modify, or delete connection profiles.

The security appliance supports IPv6 for IKEv1 IPsec LAN-to-LAN VPN connections, including support for both inside and outside networks using the inner and outer IP headers.

Fields

•

Access Interfaces—Displays a table of device interfaces where you can enable remote user access on the interface:

–

–

Interface—The device interface to enable or disable access.

Allow Access—Check to enable access by remote users.

•

Connection Profiles—Displays a table of connection profiles where you can add, edit, or delete profiles:

–

Add—Opens the Add IPsec Site-to-Site connection profile dialog box.

–

–

–

–

–

–

–

–

Edit—Opens the Edit IPsec Site-to-Site connection profile dialog box.

Delete—Removes the selected connection profile. There is no confirmation or undo.

Name—The name of the connection profile.

Interface—The interface the connection profile is enabled on.

Local Network—Specifies the IP address of the local network.

Remote Network—Specifies the IP address of the remote network.

Enabled—Enables the connection profile.

Group Policy—Shows the default group policy of the connection profile.

Add/Edit Site-to-Site Connection

The Add or Edit IPsec Site-to-Site Connection dialog box lets you create or modify an IPsec Site-to-Site connection. These dialog boxes let you specify the peer IP address (IPv4 or IPv6), specify a connection name, select an interface, specify IKE peer and user authentication parameters, specify protected networks, and specify encryption algorithms.

The adaptive security appliance supports LAN-to-LAN VPN connections to Cisco or third-party peers when the two peers have IPv4 inside and outside networks (IPv4 addresses on the inside and outside interfaces).

For LAN-to-LAN connections using mixed IPv4 and IPv6 addressing, or all IPv6 addressing, the security appliance supports VPN tunnels if both peers are Cisco ASA 5500 series security appliances, and if both inside networks have matching addressing schemes (both IPv4 or both IPv6).


•

•

The adaptive security appliances have IPv4 inside networks and the outside network is IPv6 (IPv4 addresses on the inside interfaces and IPv6 addresses on the outside interfaces).

The adaptive security appliances have IPv6 inside networks and the outside network is IPv4 (IPv6 addresses on the inside interface and IPv4 addresses on the outside interfaces).

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•

The adaptive security appliances have IPv6 inside networks and the outside network is IPv6 (IPv6 addresses on the inside and outside interfaces).

Fields

•

Peer IP Address—Lets you specify an IP address (IPv4 or IPv6) and whether that address is static.

•

•

•

Connection Name—Specifies the name assigned to this connection profile. For the Edit function, this field is display-only. You can specify that the connection name is the same as the IP address specified in the Peer IP Address field.

Interface—Selects the interface to use for this connection.

IKE Authentication—Specifies the pre-shared key and ID certificate to use when authenticating an

IKE peer.

–

Pre-shared Key—Specify the value of the pre-shared key for the tunnel group. The maximum length of the pre-shared key is 128 characters.

–

–

Identity Certificate—Specifies the name of the identity certificate, if available, to use for authentication.

Manage—Opens the Manage CA Certificates dialog box, on which you can see the certificates that are already configured, add new certificates, show details for a certificate, and edit or delete a certificate.

•

Protected Networks—Selects or specifies the local and remote network protected for this connection.

–

Local Network—Specifies the IP address of the local network.

–

–

...—Opens the Browse Local Network dialog box, in which you can select a local network.

Remote Network—Specifies the IP address of the remote network.

•

–

...—Opens the Browse Remote Network dialog box, in which you can select a remote network.

Encryption Algorithm—Specifies the encryption algorithms to use in the IKE and IPsec proposals.

–

–

IKE Proposal—Specifies one or more encryption algorithms to use for the IKE proposal.

Manage—Opens the Configure IKE Proposals dialog box.

–

IPsec Proposal—Specifies one or more encryption algorithms to use for the IPsec proposal.

Modes


Firewall Mode

Routed

•



—

•

Multiple

Context

—

System

—

Adding or Editing a Site-to-Site Tunnel Group

The Add or Edit IPsec Site-to-Site Tunnel Group dialog box lets you specify attributes for the IPsec site-to-site connection that you are adding. In addition, you can select IKE peer and user authentication parameters, configure IKE keepalive monitoring, and select the default group policy.

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Fields

•

Name—Specifies the name assigned to this tunnel group. For the Edit function, this field is display-only.

•

IKE Authentication—Specifies the pre-shared key and Identity certificate parameters to use when authenticating an IKE peer.

–

–

–

–

Pre-shared Key—Specify the value of the pre-shared key for the tunnel group. The maximum length of the pre-shared key is 128 characters.

Identity Certificate—Specifies the name of the ID certificate to use for authentication, if available.

Manage—Opens the Manage Identity Certificates dialog box, on which you can see the certificates that are already configured, add new certificates, show details for a certificate, and edit or delete a certificate.

IKE Peer ID Validation—Specifies whether to check IKE peer ID validation. The default is

Required.

•

•

IKE Keepalive ——Enables and configures IKE keepalive monitoring. You can select only one of the following attributes.

–

Disable Keep Alives—Enables or disables IKE keep alives.

–

–

Monitor Keep Alives—Enables or disables IKE keep alive monitoring. Selecting this option makes available the Confidence Interval and Retry Interval fields.

Confidence Interval—Specifies the IKE keep alive confidence interval. This is the number of seconds the adaptive security appliance should allow a peer to idle before beginning keepalive monitoring. The minimum is 10 seconds; the maximum is 300 seconds. The default for a remote access group is 10 seconds.

–

–

–

–

Retry Interval—Specifies number of seconds to wait between IKE keep alive retries. The default is 2 seconds.

Head end will never initiate keepalive monitoring—Specifies that the central-site adaptive security appliance never initiates keepalive monitoring.

Default Group Policy—Select the group policy and client protocols that you want to use as the default for this connection. A VPN group policy is a collection of user-oriented attribute-value pairs that can be stored internally on the device or externally on a RADIUS server. IPsec connections and user accounts refer to the group-policy information.

–

Group Policy—Lists the currently configured group policies. The default value is

DfltGrpPolicy.

Manage—Opens the Configure Group Policies dialog box, on which you can view the configured group policies and add, edit, or delete group policies from the list.

IPsec Protocol—Enables or disables the IPsec protocol for use by this group policy.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

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Crypto Map Entry

In this dialog box, specify crypto parameters for the Connection Profile.

Fields

•

Priority

—A unique priority (1 through 65,543, with 1 the highest priority). When IKE negotiation begins, the peer that initiates the negotiation sends all of its policies to the remote peer, and the remote peer searches for a match with its own policies, in priority order.

•

Perfect Forward Secrecy

—Ensures that the key for a given IPsec SA was not derived from any other secret (like some other keys). If someone were to break a key, PFS ensures that the attacker would not be able to derive any other key. If you enable PFS, the Diffie-Hellman Group list becomes active.

•

•

•

– Diffie-Hellman Group

—An identifier which the two IPsec peers use to derive a shared secret without transmitting it to each other. The choices are Group 1 (768-bits), Group 2 (1024-bits), and Group 5 (1536-bits).

Enable NAT-T

— Enables NAT Traversal (NAT-T) for this policy, which lets IPsec peers establish both remote access and LAN-to-LAN connections through a NAT device.

Enable Reverse Route Injection

—Provides the ability for static routes to be automatically inserted into the routing process for those networks and hosts that are protected by a remote tunnel endpoint.

Security Association Lifetime

—Configures the duration of a Security Association (SA). This parameter specifies how to measure the lifetime of the IPsec SA keys, which is how long the IPsec

SA lasts until it expires and must be renegotiated with new keys.

–

–

Time

—Specifies the SA lifetime in terms of hours (hh), minutes (mm) and seconds (ss).

Traffic Volume

—Defines the SA lifetime in terms of kilobytes of traffic. Enter the number of kilobytes of payload data after which the IPsec SA expires. Minimum is 100 KB, default is

10000 KB, maximum is 2147483647 KB.

Crypto Map Entry for Static Peer Address

In this dialog box, specify crypto parameters for the Connection Profile when the Peer IP Address is a static address.

Fields

•

Priority

—A unique priority (1 through 65,543, with 1 the highest priority). When IKE negotiation begins, the peer that initiates the negotiation sends all of its policies to the remote peer, and the remote peer searches for a match with its own policies, in priority order.

• Perfect Forward Secrecy

—Ensures that the key for a given IPsec SA was not derived from any other secret (like some other keys). If someone were to break a key, PFS ensures that the attacker would not be able to derive any other key. If you enable PFS, the Diffie-Hellman Group list becomes active.

–

Diffie-Hellman Group


• Enable NAT-T

— Enables NAT Traversal (NAT-T) for this policy, which lets IPsec peers establish both remote access and LAN-to-LAN connections through a NAT device.

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•

•

•

Enable Reverse Route Injection

—Provides the ability for static routes to be automatically inserted into the routing process for those networks and hosts that are protected by a remote tunnel endpoint.

Security Association Lifetime

—Configures the duration of a Security Association (SA). This parameter specifies how to measure the lifetime of the IPsec SA keys, which is how long the IPsec

SA lasts until it expires and must be renegotiated with new keys.

–

Time

—Specifies the SA lifetime in terms of hours (hh), minutes (mm) and seconds (ss).

– Traffic Volume

—Defines the SA lifetime in terms of kilobytes of traffic. Enter the number of kilobytes of payload data after which the IPsec SA expires. Minimum is 100 KB, default is

10000 KB, maximum is 2147483647 KB.

Static Crypto Map Entry Parameters

—Configure these additional parameters when the Peer IP

Address is specified as Static:

–

–

Connection Type

—Specify the allowed negotiation as bidirectional, answer-only, or originate-only.

Send ID Cert. Chain

—Enables transmission of the entire certificate chain.

–

–

IKE Negotiation Mode

—Sets the mode for exchanging key information for setting up the SAs,

Main or Aggressive. It also sets the mode that the initiator of the negotiation uses; the responder auto-negotiates. Aggressive Mode is faster, using fewer packets and fewer exchanges, but it does not protect the identity of the communicating parties. Main Mode is slower, using more packets and more exchanges, but it protects the identities of the communicating parties. This mode is more secure and it is the default selection. If you select Aggressive, the Diffie-Hellman

Group list becomes active.

Diffie-Hellman Group


Managing CA Certificates

Clicking Manage under IKE Peer Authentication opens the Manage CA Certificates dialog box. Use this dialog box to view, add, edit, and delete entries on the list of CA certificates available for IKE peer authentication.

The Manage CA Certificates dialog box lists information about currently configured certificates, including information about whom the certificate was issued to, who issued the certificate, when the certificate expires, and usage data.

Fields

•

Add or Edit—Opens the Install Certificate dialog box or the Edit Certificate dialog box, which let you specify information about and install a certificate.

•

•

Show Details—Displays detailed information about a certificate that you select in the table.

Delete—Removes the selected certificate from the table. There is no confirmation or undo.

Modes


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Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—


Use this dialog box to install a new CA certificate. You can get the certificate in one of the following ways:

•

•

•

Install from a file by browsing to the certificate file.

Paste the previously acquired certificate text in PEM format into the box on this dialog box.

Use SCEP—Specifies the use of the Simple Certificate Enrollment Protocol (SCEP) Add-on for

Certificate Services runs on the Windows Server 2003 family. It provides support for the SCEP protocol, which allows Cisco routers and other intermediate network devices to obtain certificates.

–

SCEP URL: http://—Specifies the URL from which to download SCEP information.

•

–

–

Retry Period—Specifies the number of minutes that must elapse between SCEP queries.

Retry Count—Specifies the maximum number of retries allowed.

More Options—Opens the Configure Options for CA Certificate dialog box.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Configure Options for CA Certificate

Use this dialog box to specify details about retrieving CA Certificates for this IPsec remote access connection. The dialog boxes on this dialog box are: Revocation Check, CRL Retrieval Policy, CRL

Retrieval Method, OCSP Rules, and Advanced.

Revocation Check Dialog Box

Use this dialog box to specify information about CA Certificate revocation checking.

Fields

•

The radio buttons specify whether to check certificates for revocation. The values of these buttons are as follows:

–

Do not check certificates for revocation

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•

–

Check Certificates for revocation

Revocation Methods area—Lets you specify the method–CRL or OCSP–to use for revocation checking, a nd the order in which to use these methods. You can choose either or both methods.

Add/Edit Remote Access Connections > Advanced > General

Use this dialog box to specify whether to strip the realm and group from the username before passing them to the AAA server, and to specify password management parameters.

Fields

•

Strip the realm from username before passing it on to the AAA server—Enables or disables stripping the realm (administrative domain) from the username before passing the username on to the AAA server. Check the Strip Realm check box to remove the realm qualifier of the username during authentication. You can append the realm name to the username for AAA: authorization, authentication and accounting. The only valid delimiter for a realm is the @ character. The format is username@realm, for example, [email protected]. If you check this Strip Realm check box, authentication is based on the username alone. Otherwise, authentication is based on the full username@realm string. You must check this box if your server is unable to parse delimiters.

Note

You can append both the realm and the group to a username, in which case the adaptive security appliance uses parameters configured for the group and for the realm for AAA functions. The format for this option is username[@realm]]<#or!>group], for example,

[email protected]#VPNGroup. If you choose this option, you must use either the # or ! character for the group delimiter because the adaptive security appliance cannot interpret the @ as a group delimiter if it is also present as the realm delimiter.

A Kerberos realm is a special case. The convention in naming a Kerberos realm is to capitalize the DNS domain name associated with the hosts in the Kerberos realm. For example, if users are in the it.cisco.com domain, you might call your Kerberos realm IT.CISCO.COM.

The adaptive security appliance does not include support for the user@grouppolicy, as the VPN

3000 Concentrator did. Only the L2TP/IPsec client supports the tunnel switching via user@tunnelgroup.

•

•

Strip the group from the username before passing it on to the AAA server—Enables or disables stripping the group name from the username before passing the username on to the AAA server.

Check Strip Group to remove the group name from the username during authentication. This option is meaningful only when you have also checked the Enable Group Lookup box. When you append a group name to a username using a delimiter, and enable Group Lookup, the adaptive security appliance interprets all characters to the left of the delimiter as the username, and those to the right as the group name. Valid group delimiters are the @, #, and ! characters, with the @ character as the default for Group Lookup. You append the group to the username in the format

username<delimiter>group

, the possibilities being, for example,

JaneDoe@VPNGroup,

JaneDoe#VPNGroup

, and

JaneDoe!VPNGroup

.


–


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Note


–

Enable notification upon password expiration to allow user to change password—Checking this check box makes the following two parameters available. You can select either to notify the user at login a specific number of days before the password expires or to notify the user only on the day that the password expires. The default is to notify the user 14 days prior to password expiration and every day thereafter until the user changes the password. The range is 1 through

180 days.

Note





This feature requires the use of MS-CHAPv2.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Configuring Client Addressing

To specify the client IP address assignment policy and assign address pools to all IPsec and SSL VPN connections, choose Config > Remote Access VPN > Network (Client) Access > IPsec or SSL VPN

Connections > Add or Edit > Advanced > Client Addressing. The Add IPsec Remote Access Connection or Add SSL VPN Access Connection opens. Use this dialog box to add address pools and assign them to interfaces, and view, edit, or delete them. The table at the bottom of the dialog box lists the configured interface-specific address pools.

To understand the fields in this dialog box or its descendent dialog boxes, see the sections that follow this one. You can view or change the configuration of address pools and their assignment to interfaces, as follows:

•

To view or change the configuration of address pools, click

Add

or

Edit

in the Add IPsec Remote

Access Connection or Add SSL VPN Access Connection dialog box. The Assign Address Pools to

Interface dialog box opens. This dialog box lets you assign IP address pools to the interfaces configured on the adaptive security appliance. Click

Select

. The Select Address Pools dialog box opens. Use this dialog box to view the configuration of address pools. You can change their address pool configuration as follows:

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–

–

To add an address pool to the adaptive security appliance, choose

Add

. The Add IP Pool dialog box opens.

To change the configuration of an address pool on the adaptive security appliance, choose

Edit

.

The Edit IP Pool dialog box opens if the addresses in the pool are not in use.

Note

You cannot modify an address pool if it is already in use. If you click

Edit

and the address pool is in use, ASDM displays an error message and lists the connection names and usernames that are using the addresses in the pool.

–

To remove address pool on the adaptive security appliance, select the entry in the table and click

Delete

.

Note

You cannot remove an address pool if it is already in use. If you click

Delete

and the address pool is in use, ASDM displays an error message and lists the connection names that are using the addresses in the pool.

•

•

•

To assign address pools to an interface, click

Add

in the Add IPsec Remote Access Connection or

Add SSL VPN Access Connection dialog box. The Assign Address Pools to Interface dialog box opens. Select the interface to be assigned an address pool. Click

Select

next to the Address Pools field. The Select Address Pools dialog box opens. Double-click each unassigned pool you want to assign to the interface or choose each unassigned pool and click

Assign

. The adjacent field displays the list of pool assignments. Click OK to populate the Address Pools field with the names of these address pools, then

OK

again to complete the configuration of the assignment.

To change the address pools assigned to an interface, double-click the interface, or choose the interface in the Add IPsec Remote Access Connection or Add SSL VPN Access Connection dialog box and click Edit. The Assign Address Pools to Interface dialog box opens. To remove address pools, double-click each pool name and press the Delete button on the keyboard. Click

Select

next to the Address Pools field if you want to assign additional fields to the interface. The Select Address

Pools dialog box opens. Note that the Assign field displays the address pool names that remained assigned to the interface. Double-click each unassigned pool you want to add to the interface. The

Assign field updates the list of pool assignments. Click

OK

to revise the Address Pools field with the names of these address pools, then

OK

again to complete the configuration of the assignment.

To remove an entry from the Add IPsec Remote Access Connection or Add SSL VPN Access

Connection dialog box, choose the entry and click

Delete

.

The Add IPsec Remote Access Connection and Add SSL VPN Access Connection dialog boxes and their descendent dialog boxes are identical. Use the following sections to understand or assign values to the fields in these dialog boxes:

•

Add IPsec Remote Access Connection and Add SSL VPN Access Connection

•

•

Assign Address Pools to Interface

Select Address Pools

•

•

Add or Edit IP Pool

Add or Edit IP Pool

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Add IPsec Remote Access Connection and Add SSL VPN Access Connection

To access the Add IPsec Remote Access Connection and Add SSL VPN Access Connection dialog boxes, choose Config > Remote Access VPN > Network (Client) Access > IPsec or SSL VPN

Connections > Add or Edit > Advanced > Client Addressing.

Fields

Use the following descriptions to assign values to the fields in this dialog box:

•

Global Client Address Assignment Policy—Configures a policy that affects all IPsec and SSL VPN

Client connections (including AnyConnect client connections). The adaptive security appliance uses the selected sources in order, until it finds an address:

•

–

–

Use authentication server—Specifies that the adaptive security appliance should attempt to use the authentication server as the source for a client address.

Use DHCP—Specifies that the adaptive security appliance should attempt to use DHCP as the source for a client address.

–

Use address pool—Specifies that the adaptive security appliance should attempt to use address pools as the source for a client address.

Interface-Specific Address Pools—Lists the configured interface-specific address pools.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Assign Address Pools to Interface

Use the Assign Address Pools to Interface dialog box to select an interface and assign one or more address pools to that interface. To access this dialog box, choose Config > Remote Access VPN >

Network (Client) Access > IPsec or SSL VPN Connections > Add or Edit > Advanced > Client

Addressing > Add or Edit.

Fields


•

Interface—Select the interface to which you want to assign an address pool. The default is DMZ.

•

•

Address Pools—Specify an address pool to assign to the specified interface.

Select—Opens the Select Address Pools dialog box, in which you can select one or more address pools to assign to this interface. Your selection appears in the Address Pools field of the Assign

Address Pools to Interface dialog box.

Modes


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Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Select Address Pools

The Select Address Pools dialog box shows the pool name, starting and ending addresses, and subnet mask of address pools available for client address assignment and lets you add, edit, or delete entries from that list. To access this dialog box, choose Config > Remote Access VPN > Network (Client)

Access > IPsec or SSL VPN Connections > Add or Edit > Advanced > Client Addressing > Add or Edit

> Select.

Fields


•

•

•

Add—Opens the Add IP Pool dialog box, on which you can configure a new IP address pool.

Edit—Opens the Edit IP Pool dialog box, on which you can modify a selected IP address pool.

•

Delete—Removes the selected address pool. There is no confirmation or undo.

Assign—Displays the address pool names that remained assigned to the interface. Double-click each unassigned pool you want to add to the interface. The Assign field updates the list of pool assignments.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add or Edit IP Pool

The Add or Edit IP Pool dialog box lets you specify or modify a range of IP addresses for client address assignment. To access this dialog box, choose Config > Remote Access VPN > Network (Client) Access

> IPsec or SSL VPN Connections > Add or Edit > Advanced > Client Addressing > Add or Edit > Select

> Add or Edit.

•

•

•

Fields


•

Name—Specifies the name assigned to the IP address pool.

Starting IP Address—Specifies the first IP address in the pool.

Ending IP Address—Specifies the last IP address in the pool.

Subnet Mask—Selects the subnet mask to apply to the addresses in the pool.

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Modes



Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit SSL VPN Connections > Advanced > Accounting

The settings on this dialog box apply to the connection (tunnel group) globally across the adaptive security appliance. This dialog box lets you configure the following attribute:

•

Accounting Server Group—Lists the available accounting server groups. You can also select None

(the default). LOCAL is not an option.

•


Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit Tunnel Group > General > Client Address Assignment

To specify whether to use DHCP or address pools for address assignment, go to Configuration > VPN >

I P Address Management > Assignment. The Add or Edit Tunnel Group dialog box > General > Client

Address Assignment dialog box, lets you configure the following Client Address Assignment attributes:

•

DHCP Servers—Specifies a DHCP server to use. You can add up to 10 servers, one at a time.

•

–

–

IP Address—Specifies the IP address of a DHCP server.

Add—Adds the specified DHCP server to the list for client address assignment.

–

Delete—Deletes the specified DHCP server from the list for client address assignment. There is no confirmation or undo.

Address Pools—Lets you specify up to 6 address pools, using the following parameters:

–

–

Available Pools—Lists the available, configured address pools you can choose.

Add—Adds the selected address pool to the list for client address assignment.

–

–

Remove—Moves the selected address pool from the Assigned Pools list to the Available Pools list.

Assigned Pools—Lists the address pools selected for address assignment.

Note

To configure interface-specific address pools, click Advanced.

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Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit Tunnel Group > General > Advanced

The Add or Edit Tunnel Group dialog box, General, Advanced dialog box, lets you configure the following interface-specific attributes:

•

Interface-Specific Authentication Server Groups—Lets you configure an interface and server group for authentication.

–

–

Interface—Lists available interfaces for selection.

Server Group—Lists authentication server groups available for this interface.

–

–

–

–

Use LOCAL if server group fails—Enables or disables fallback to the LOCAL database if the server group fails.

Add—Adds the association between the selected available interface and the authentication server group to the assigned list.

Remove—Moves the selected interface and authentication server group association from the assigned list to the available list.

Interface/Server Group/Use Fallback—Show the selections you have added to the assigned list.

•

Interface-Specific Client IP Address Pools—-Lets you specify an interface and Client IP address pool. You can have up to 6 pools.

–

Interface—Lists the available interfaces to add.

–

–

Address Pool—Lists address pools available to associate with this interface.

Add—Adds the association between the selected available interface and the client IP address pool to the assigned list.

–

–

Remove—Moves the selected interface/address pool association from the assigned list to the available list.

Interface/Address Pool—Shows the selections you have added to the assigned list.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

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Add/Edit Tunnel Group > IPsec for Remote Access > IPsec

On the Add or Edit Tunnel Group dialog box for IPsec for Remote Access, the IPsec dialog box lets you configure or edit IPsec-specific tunnel group parameters.

Fields

•

Pre-shared Key—Lets you specify the value of the pre-shared key for the tunnel group. The maximum length of the pre-shared key is 128 characters.

•

•

Trustpoint Name—Selects a trustpoint name, if any trustpoints are configured. A trustpoint is a representation of a certificate authority. A trustpoint contains the identity of the CA, CA-specific configuration parameters, and an association with one enrolled identity certificate.

Authentication Mode—Specifies the authentication mode: none, xauth, or hybrid.

–

–

none—Specifies no authentication mode.

xauth—Specifies the use of IKE Extended Authentication mode, which provides the capability of authenticating a user within IKE using TACACS+ or RADIUS.

–

1.

2.

hybrid—Specifies the use of Hybrid mode, which lets you use digital certificates for security appliance authentication and a different, legacy method—such as RADIUS, TACACS+ or

SecurID—for remote VPN user authentication. This mode breaks phase 1 of the Internet Key

Exchange (IKE) into the following steps, together called hybrid authentication:

The security appliance authenticates to the remote VPN user with standard public key techniques. This establishes an IKE security association that is unidirectionally authenticated.

An extended authentication (xauth) exchange then authenticates the remote VPN user. This extended authentication can use one of the supported legacy authentication methods.

Note

Before setting the authentication type to hybrid, you must configure the authentication server and create a pre-shared key.

•

•

•

•

IKE Peer ID Validation—Selects whether IKE peer ID validation is ignored, required, or checked only if supported by a certificate.

Enable sending certificate chain—Enables or disables sending the entire certificate chain. This action includes the root certificate and any subordinate CA certificates in the transmission.

ISAKMP Keep Alive—Enables and configures ISAKMP keep alive monitoring.

–

Disable Keep Alives—Enables or disables ISAKMP keep alives.

–

–

Monitor Keep Alives—Enables or disables ISAKMP keep alive monitoring. Selecting this option makes available the Confidence Interval and Retry Interval fields.

Confidence Interval—Specifies the ISAKMP keep alive confidence interval. This is the number of seconds the adaptive security appliance should allow a peer to idle before beginning keepalive monitoring. The minimum is 10 seconds; the maximum is 300 seconds. The default for a remote access group is 300 seconds.

–

–

Retry Interval—Specifies number of seconds to wait between ISAKMP keep alive retries. The default is 2 seconds.


Interface-Specific Authentication Mode—Specifies the authentication mode on a per-interface basis.

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•

–

–

–

Interface—Lets you select the interface name. The default interfaces are inside and outside, but if you have configured a different interface name, that name also appears in the list.

Authentication Mode—Lets you select the authentication mode, none, xauth, or hybrid, as above.

Interface/Authentication Mode table—Shows the interface names and their associated authentication modes that are selected.

–

–

Client VPN Software Update Table—Lists the client type, VPN Client revisions, and image URL for each client VPN software package installed. For each client type, you can specify the acceptable client software revisions and the URL or IP address from which to download software upgrades, if necessary. The client update mechanism (described in detail under the Client Update dialog box) uses this information to determine whether the software each VPN client is running is at an appropriate revision level and, if appropriate, to provide a notification message and an update mechanism to clients that are running outdated software.

–

Client Type—Identifies the VPN client type.

–

–

Add—Adds an interface/authentication mode pair selection to the Interface/Authentication

Modes table.

Remove—Removes an interface/authentication mode pair selection from the

Interface/Authentication Modes table.

VPN Client Revisions—Specifies the acceptable revision level of the VPN client.

Image URL—Specifies the URL or IP address from which the correct VPN client software image can be downloaded. For dialog boxes-based VPN clients, the URL must be of the form http:// or https://. For ASA 5505 in client mode or VPN 3002 hardware clients, the URL must be of the form tftp://.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add/Edit Tunnel Group for Site-to-Site VPN

The Add or Edit Tunnel Group dialog box lets you configure or edit tunnel group parameters for this

Site-to-Site connection profile.

Fields

•

Certificate Settings—Sets the following certificate chain and IKE peer validation attributes:

–

–

Send certificate chain—Enables or disables sending the entire certificate chain. This action includes the root certificate and any subordinate CA certificates in the transmission.


•

IKE Keep Alive—Enables and configures IKE (ISAKMP) keepalive monitoring.

–

Disable Keepalives—Enables or disables IKE keep alives.

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•

–

Monitor Keepalives—Enables or disables IKE keep alive monitoring. Selecting this option makes available the Confidence Interval and Retry Interval fields.

–

–

Confidence Interval—Specifies the IKE keepalive confidence interval. This is the number of seconds the adaptive security appliance should allow a peer to idle before beginning keepalive monitoring. The minimum is 10 seconds; the maximum is 300 seconds. The default for a remote access group is 300 seconds.

Retry Interval—Specifies number of seconds to wait between IKE keepalive retries. The default is 2 seconds.

–


Default Group Policy—Specifies the following group-policy attributes:

–

–

Group Policy—Selects a group policy to use as the default group policy. The default value is

DfltGrpPolicy.

Manage—Opens the Configure Group Policies dialog box.

–

IPsec Protocol—Enables or disables the use of the IPsec protocol for this connection profile.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit Tunnel Group > PPP

On the Add or Edit Tunnel Group dialog box for a IPsec remote access tunnel group, the PPP dialog box lets you configure or edit the authentication protocols permitted of a PPP connection. This dialog box applies

only

to IPsec remote access tunnel groups.

Fields

•

CHAP—Enables the use of the CHAP protocol for a PPP connection.

•

MS-CHAP-V1—Enables the use of the MS-CHAP-V1 protocol for a PPP connection.

•

•

•

MS-CHAP-V2—Enables the use of the MS-CHAP-V2 protocol for a PPP connection.

PAP—Enables the use of the PAP protocol for a PPP connection.

EAP-PROXY—Enables the use of the EAP-PROXY protocol for a PPP connection. EAP refers to the Extensible Authentication protocol.

Modes


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Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit Tunnel Group > IPsec for LAN to LAN Access > General > Basic

On the Add or Edit Tunnel Group dialog box for Site-to-Site Remote Access, the General, Basic dialog box you can specify a name for the tunnel group that you are adding (Add function only) and select the group policy.

On the Edit Tunnel Group dialog box, the General dialog box displays the name and type of the tunnel group you are modifying.

Fields

•


•

•

Type—(

Display-only

) Displays the type of tunnel group you are adding or editing. The contents of this field depend on your selection on the previous dialog box.

Group Policy—Lists the currently configured group policies. The default value is the default group policy, DfltGrpPolicy.

•

Strip the realm (administrative domain) from the username before passing it on to the AAA server—Enables or disables stripping the realm from the username before passing the username on to the AAA server. Check the Strip Realm check box to remove the realm qualifier of the username during authentication. You can append the realm name to the username for AAA: authorization, authentication and accounting. The only valid delimiter for a realm is the @ character. The format is username@realm, for example, [email protected]. If you check this Strip Realm check box, authentication is based on the username alone. Otherwise, authentication is based on the full username@realm string. You must check this box if your server is unable to parse delimiters.

Note






•


Check Strip Group to remove the group name from the username during authentication. This option

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•

is meaningful only when you have also checked the Enable Group Lookup box. When you append a group name to a username using a delimiter, and enable Group Lookup, the adaptive security appliance interprets all characters to the left of the delimiter as the username, and those to the right as the group name. Valid group delimiters are the @, #, and ! characters, with the @ character as the default for Group Lookup. You append the group to the username in the format



JaneDoe@VPNGroup,

JaneDoe#VPNGroup

, and

JaneDoe!VPNGroup

.


–


Note


–

Enable notification upon password expiration to allow user to change password—Checking this check box makes the following two parameters available. If you do not also check the Enable notification prior to expiration check box, the user receives notification only after the password has expired.

–

–

Enable notification prior to expiration—When you check this option, the adaptive security appliance notifies the remote user at login that the current password is about to expire or has expired, then offers the user the opportunity to change the password. If the current password has not yet expired, the user can still log in using that password. This parameter is valid for AAA servers that support such notification; that is, RADIUS, RADIUS with an NT server, and LDAP servers. The adaptive security appliance ignores this command if RADIUS or LDAP authentication has not been configured.

Note that this does not change the number of days before the password expires, but rather, it enables the notification. If you check this check box, you must also specify the number of days.

Notify...days prior to expiration—Specifies the number of days before the current password expires to notify the user of the pending expiration. The range is 1 through 180 days.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit Tunnel Group > IPsec for LAN to LAN Access > IPsec

The Add or Edit Tunnel Group dialog box for IPsec for Site-to-Site access, IPsec dialog box, lets you configure or edit IPsec Site-to-Site-specific tunnel group parameters.

Fields

•


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•

•

•

•

Type—(

Display-only

) Displays the type of tunnel group you are adding or editing. The contents of this field depend on your selection on the previous dialog box.

Pre-shared Key—Lets you specify the value of the pre-shared key for the tunnel group. The maximum length of the pre-shared key is 128 characters.

Trustpoint Name—Selects a trustpoint name, if any trustpoints are configured. A trustpoint is a representation of a certificate authority. A trustpoint contains the identity of the CA, CA-specific configuration parameters, and an association with one enrolled identity certificate.

Authentication Mode—Specifies the authentication mode: none, xauth, or hybrid.

–

none—Specifies no authentication mode.

–

–

xauth—Specifies the use of IKE Extended Authentication mode, which provides the capability of authenticating a user within IKE using TACACS+ or RADIUS. hybrid—Specifies the use of Hybrid mode, which lets you use digital certificates for security appliance authentication and a different, legacy method—such as RADIUS, TACACS+ or

SecurID—for remote VPN user authentication. This mode breaks phase 1 of the Internet Key

Exchange (IKE) into the following steps, together called hybrid authentication:

1.

2.

The security appliance authenticates to the remote VPN user with standard public key techniques. This establishes an IKE security association that is unidirectionally authenticated.

An extended authentication (xauth) exchange then authenticates the remote VPN user. This extended authentication can use one of the supported legacy authentication methods.

Note

Before setting the authentication type to hybrid, you must configure the authentication server and create a pre-shared key.

•

•

•

•


Enable sending certificate chain—Enables or disables sending the entire certificate chain. This action includes the root certificate and any subordinate CA certificates in the transmission.

ISAKMP Keep Alive—Enables and configures ISAKMP keep alive monitoring.

–

Disable Keep Alives—Enables or disables ISAKMP keep alives.

–

–

–

Monitor Keep Alives—Enables or disables ISAKMP keep alive monitoring. Selecting this option makes available the Confidence Interval and Retry Interval fields.

Confidence Interval—Specifies the ISAKMP keep alive confidence interval. This is the number of seconds the adaptive security appliance should allow a peer to idle before beginning keepalive monitoring. The minimum is 10 seconds; the maximum is 300 seconds. The default for a remote access group is 300 seconds.

Retry Interval—Specifies number of seconds to wait between ISAKMP keep alive retries. The default is 2 seconds.

–


Interface-Specific Authentication Mode—Specifies the authentication mode on a per-interface basis.

–

Interface—Lets you select the interface name. The default interfaces are inside and outside, but if you have configured a different interface name, that name also appears in the list.

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•

–

Authentication Mode—Lets you select the authentication mode, none, xauth, or hybrid, as above.

–

–

Interface/Authentication Mode table—Shows the interface names and their associated authentication modes that are selected.

Add—Adds an interface/authentication mode pair selection to the Interface/Authentication

Modes table.

–

Remove—Removes an interface/authentication mode pair selection from the

Interface/Authentication Modes table.

Client VPN Software Update Table—Lists the client type, VPN Client revisions, and image URL for each client VPN software package installed. For each client type, you can specify the acceptable client software revisions and the URL or IP address from which to download software upgrades, if necessary. The client update mechanism (described in detail under the Client Update dialog box) uses this information to determine whether the software each VPN client is running is at an appropriate revision level and, if appropriate, to provide a notification message and an update mechanism to clients that are running outdated software.

–

–

Client Type—Identifies the VPN client type.

VPN Client Revisions—Specifies the acceptable revision level of the VPN client.

–

Image URL—Specifies the URL or IP address from which the correct VPN client software image can be downloaded. For Windows-based VPN clients, the URL must be of the form http:// or https://. For ASA 5505 in client mode or VPN 3002 hardware clients, the URL must be of the form tftp://.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Clientless SSL VPN Access > Connection Profiles > Add/Edit > General > Basic

The Add or Edit pane, General, Basic dialog box lets you specify a name for the tunnel group that you are adding, lets you select the group policy, and lets you configure password management.

On the Edit Tunnel Group dialog box, the General dialog box displays the name and type of the selected tunnel group. All other functions are the same as for the Add Tunnel Group dialog box.

Fields

•


•

•

Type—Displays the type of tunnel group you are adding or editing. For Edit, this is a display-only field whose contents depend on your selection in the Add dialog box.

Group Policy—Lists the currently configured group policies. The default value is the default group policy, DfltGrpPolicy.

•

Strip the realm —Not available for Clientless SSL VPN.

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•

•

Strip the group —Not available or Clientless SSL VPN.


–


Note


–

–

–

Enable notification upon password expiration to allow user to change password—Checking this check box makes the following two parameters available. If you do not also check the Enable notification prior to expiration check box, the user receives notification only after the password has expired.

Enable notification prior to expiration—When you check this option, the adaptive security appliance notifies the remote user at login that the current password is about to expire or has expired, then offers the user the opportunity to change the password. If the current password has not yet expired, the user can still log in using that password. This parameter is valid for AAA servers that support such notification; that is, RADIUS, RADIUS with an NT server, and LDAP servers. The adaptive security appliance ignores this command if RADIUS or LDAP authentication has not been configured.

Note that this does not change the number of days before the password expires, but rather, it enables the notification. If you check this check box, you must also specify the number of days.

Notify...days prior to expiration—Specifies the number of days before the current password expires to notify the user of the pending expiration. The range is 1 through 180 days.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Configuring Internal Group Policy IPsec Client Attributes

Use this dialog box to specify whether to strip the realm and group from the username before passing them to the AAA server, and to specify password management options.

Fields

•

Strip the realm from username before passing it on to the AAA server—Enables or disables stripping the realm (administrative domain) from the username before passing the username on to the AAA server. Check the Strip Realm check box to remove the realm qualifier of the username during authentication. You can append the realm name to the username for AAA: authorization, authentication and accounting. The only valid delimiter for a realm is the @ character. The format is username@realm, for example, [email protected]. If you check this Strip Realm check box, authentication is based on the username alone. Otherwise, authentication is based on the full username@realm string. You must check this box if your server is unable to parse delimiters.

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Note






•

•


Check Strip Group to remove the group name from the username during authentication. This option is meaningful only when you have also checked the Enable Group Lookup box. When you append a group name to a username using a delimiter, and enable Group Lookup, the adaptive security appliance interprets all characters to the left of the delimiter as the username, and those to the right as the group name. Valid group delimiters are the @, #, and ! characters, with the @ character as the default for Group Lookup. You append the group to the username in the format



JaneDoe@VPNGroup,

JaneDoe#VPNGroup

, and

JaneDoe!VPNGroup

.


–


Note


–

Enable notification upon password expiration to allow user to change password—Checking this check box makes the following two parameters available. You can select either to notify the user at login a specific number of days before the password expires or to notify the user only on the day that the password expires. The default is to notify the user 14 days prior to password expiration and every day thereafter until the user changes the password. The range is 1 through

180 days.

Note





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Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Configuring Client Addressing for SSL VPN Connections

Use this dialog box to specify the global client address assignment policy and to configure interface-specific address pools. You can also add, edit, or delete interface-specific address pools using this dialog box. The table at the bottom of the dialog box lists the configured interface-specific address pools.

Fields

•

Global Client Address Assignment Policy—Configures a policy that affects all IPsec and SSL VPN

Client connections (including AnyConnect client connections). The adaptive security appliance uses the selected sources in order, until it finds an address:

–

Use authentication server—Specifies that the adaptive security appliance should attempt to use the authentication server as the source for a client address.

•

•

•

•

–

–

Use DHCP—Specifies that the adaptive security appliance should attempt to use DHCP as the source for a client address.

Use address pool—Specifies that the adaptive security appliance should attempt to use address pools as the source for a client address.

Interface-Specific Address Pools—Lists the configured interface-specific address pools.

Add—Opens the Assign Address Pools to Interface dialog box, on which you can select an interface and select an address pool to assign.

Edit—Opens the Assign Address Pools to Interface dialog box with the interface and address pool fields filled in.

Delete—Deletes the selected interface-specific address pool. There is no confirmation or undo.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Assign Address Pools to Interface

Use this dialog box to select an interface and assign one or more address pools to that interface.

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Fields

•

Interface—Select the interface to which you want to assign an address pool. The default is DMZ.

•

Address Pools—Specify an address pool to assign to the specified interface.

•

Select—Opens the Select Address Pools dialog box, in which you can select one or more address pools to assign to this interface. Your selection appears in the Address Pools field of the Assign

Address Pools to Interface dialog box.

Select Address Pools

The Select Address Pools dialog box shows the pool name, starting and ending addresses, and subnet mask of address pools available for client address assignment and lets you add, edit, or delete entries from that list.

Fields

•

Add—Opens the Add IP Pool dialog box, on which you can configure a new IP address pool.

•

Edit—Opens the Edit IP Pool dialog box, on which you can modify a selected IP address pool.

•

•

Delete—Removes the selected address pool. There is no confirmation or undo.

Assign—Displays the address pool names that remained assigned to the interface. Double-click each unassigned pool you want to add to the interface. The Assign field updates the list of pool assignments.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add or Edit an IP Address Pool

Configures or modifies an IP address pool.

Fields

•

Name—Specifies the name assigned to the IP address pool.

•

•

•

Starting IP Address—Specifies the first IP address in the pool.

Ending IP Address—Specifies the last IP address in the pool.

Subnet Mask—Selects the subnet mask to apply to the addresses in the pool.

Modes


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System Options

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Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Authenticating SSL VPN Connections

The SSL VPN Connections > Advanced > Authentication dialog box lets you configure authentication attributes for SSL VPN connections.

System Options

The System Options pane lets you configure features specific to VPN sessions on the adaptive security appliance.

Fields

•

Enable inbound IPsec sessions to bypass interface access-lists. Group policy and per-user authorization access lists still apply to the traffic—By default, the adaptive security appliance allows

VPN traffic to terminate on a adaptive security appliance interface; you do not need to allow IKE or

ESP (or other types of VPN packets) in an access rule. When this option is checked, you also do not need an access rule for local IP addresses of decrypted VPN packets. Because the VPN tunnel was terminated successfully using VPN security mechanisms, this feature simplifies configuration and maximizes the adaptive security appliance performance without any security risks. (Group policy and per-user authorization access lists still apply to the traffic.)

•

You can require an access rule to apply to the local IP addresses by unchecking this option. The access rule applies to the local IP address, and not to the original client IP address used before the

VPN packet was decrypted.

Limit the maximum number of active IPsec VPN sessions—Enables or disables limiting the maximum number of active IPsec VPN sessions. The range depends on the hardware platform and the software license.

•

•

–

Maximum Active IPsec VPN Sessions—Specifies the maximum number of active IPsec VPN sessions allowed. This field is active only when you select the preceding check box to limit the maximum number of active IPsec VPN sessions.

L2TP Tunnel Keep-alive Timeout—Specifies the frequency, in seconds, of keepalive messages. The range is 10 through 300 seconds. The default is 60 seconds.

Preserve stateful VPN flows when tunnel drops for Network-Extension Mode (NEM)—Enables or disables preserving IPsec tunneled flows in Network-Extension Mode. With the persistent IPsec tunneled flows feature enabled, as long as the tunnel is recreated within the timeout dialog box, data continues flowing successfully because the security appliance still has access to the state information. This option is disabled by default.

Note

Tunneled TCP flows are not dropped, so they rely on the TCP timeout for cleanup. However, if the timeout is disabled for a particular tunneled flow, that flow remains in the system until being cleared manually or by other means (for example, by a TCP RST from the peer).


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Zone Labs Integrity Server

Modes



Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Configuring SSL VPN Connections, Advanced

The advanced options include configuring split tunneling, IE browser proxy, and group-policy related attributes for SSL VPN/AnyConnect clients and IPsec clients.

Configuring Split Tunneling

Split tunneling lets you specify that certain data traffic is encrypted (“goes through the tunnel”), while the remainder is sent in the clear (unencrypted). Split-tunneling network lists distinguish networks that require traffic to go through the tunnel from those that do not require tunneling. the adaptive security appliance makes split-tunneling decisions based on a network list, which is an ACL consisting of a list of addresses on the private network.

Fields

•

•

•

•

DNS Names—Specify one or more DNS names to which this policy applies.

Policy—Selects the split-tunneling policy, specifying whether to include or exclude from the tunnel the indicated network lists. If you do not select Inherit, the default is Exclude Network List Below.

Network List—Selects the networks to which to apply the split-tunneling policy. If you do not select

Inherit, the default is --None--.

Manage—Opens the ACL Manager dialog box, in which you can configure access control lists to use as network lists.

•

Intercept DHCP Configuration Message from Microsoft Clients—Reveals additional parameters specific to DHCP Intercept. DCHP Intercept lets Microsoft XP clients use split-tunneling with the adaptive security appliance. For Windows clients prior to XP, DHCP Intercept provides the domain name and subnet mask.

–

Intercept—Specifies whether to allow the DHCP Intercept to occur. If you do not select, Inherit, the default setting is No.

–

Subnet Mask—Selects the subnet mask to use.


The Zone Labs Integrity Server panel lets you configure the adaptive security appliance to support a

Zone Labs Integrity Server. This server is part of the Integrity System, a system designed to enforce security policies on remote clients entering the private network. In essence, the adaptive security appliance acts as a proxy for the client PC to the Firewall Server and relays all necessary Integrity information between the Integrity client and the Integrity server.

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Note

The current release of the security appliance supports one Integrity Server at a time even though the user interfaces support the configuration of up to five Integrity Servers. If the active Server fails, configure another Integrity Server on the adaptive security appliance and then reestablish the client VPN session.

Fields

•

Server IP address—Type the IP address of the Integrity Server. Use dotted decimal notation.

•

•

•

Add—Adds a new server IP address to the list of Integrity Servers. This button is active when an address is entered in the Server IP address field.

Delete—Deletes the selected server from the list of Integrity Servers.

•

Move Up—Moves the selected server up in the list of Integrity Servers. This button is available only when there is more than one server in the list.

Move Down—Moves the selected server down in the list of Integrity Servers. This button is available only when there is more than one server in the list.

•

•

Server Port—Type the adaptive security appliance port number on which it listens to the active

Integrity server. This field is available only if there is at least one server in the list of Integrity

Servers. The default port number is 5054, and it can range from 10 to 10000. This field is only available when there is a server in the Integrity Server list.

Interface—Choose the interface adaptive security appliance interface on which it communicates with the active Integrity Server. This interface name menu is only available when there is a server in the Integrity Server list.


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Easy VPN Remote


•

•

•

•

•

•

Fail Timeout—Type the number of seconds that the adaptive security appliance should wait before it declares the active Integrity Server to be unreachable. The default is 10 and the range is from 5 to

20.

SSL Certificate Port: Specify the adaptive security appliance port to be used for SSL Authorization.

The default is port 80.

Enable SSL Authentication—Check to enable authentication of the remote client SSL certificate by the adaptive security appliance. By default, client SSL authentication is disabled.

Close connection on timeout—Check to close the connection between the adaptive security appliance and the Integrity Server on a timeout. By default, the connection remains open.

Apply—Click to apply the Integrity Server setting to the adaptive security appliance running configuration.

Reset—Click to remove Integrity Server configuration changes that have not yet been applied.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Easy VPN Remote

Easy VPN Remote lets the ASA 5505 act as an Easy VPN client device. The ASA 5505 can then initiate a VPN tunnel to an Easy VPN server, which can be a adaptive security appliance, a Cisco VPN 3000

Concentrator, an IOS-based router, or a firewall acting as an Easy VPN server.

The Easy VPN client supports one of two modes of operation: Client Mode or Network Extension Mode

(NEM). The mode of operation determines whether the Easy VPN Client inside hosts are accessible from the Enterprise network over the tunnel. Specifying a mode of operation is mandatory before making a connection because Easy VPN Client does not have a default mode.

Client mode, also called Port Address Translation (PAT) mode, isolates all devices on the Easy VPN

Client private network from those on the enterprise network. The Easy VPN Client performs Port

Address Translation (PAT) for all VPN traffic for its inside hosts. IP address management is neither required for the Easy VPN Client inside interface or the inside hosts.

NEM makes the inside interface and all inside hosts routable across the enterprise network over the tunnel. Hosts on the inside network obtain their IP addresses from an accessible subnet (statically or via

DHCP) pre-configured with static IP addresses. PAT does not apply to VPN traffic in NEM. This mode does not require a VPN configuration for each client. The Cisco ASA 5505 configured for NEM mode supports automatic tunnel initiation. The configuration must store the group name, user name, and password. Automatic tunnel initiation is disabled if secure unit authentication is enabled.

The network and addresses on the private side of the Easy VPN Client are hidden, and cannot be accessed directly.

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Easy VPN Remote

Fields

•

Enable Easy VPN Remote—Enables the Easy VPN Remote feature and makes available the rest of the fields on this dialog box for configuration.

•

Mode—Selects either Client mode or Network extension mode.

–

–

Client mode—Uses Port Address Translation (PAT) mode to isolate the addresses of the inside hosts, relative to the client, from the enterprise network.

Network extension mode—Makes those addresses accessible from the enterprise network.

Note

If the Easy VPN Remote is using NEM and has connections to secondary servers, establish an ASDM connection to each headend and check Enable Reverse Route

Injection on the Configuration > VPN > IPsec > IPsec Rules > Tunnel Policy (Crypto

Map) - Advanced dialog box to configure dynamic announcements of the remote network using RRI.

•

•

–

Group Settings—Specifies whether to use a pre-shared key or an X.509 certificate for user authentication.

–

Pre-shared key—Enables the use of a pre-shared key for authentication and makes available the subsequent Group Name, Group Password, and Confirm Password fields for specifying the group policy name and password containing that key.

–

Auto connect—The Easy VPN Remote establishes automatic IPsec data tunnels unless both of the following are true: Network extension mode is configured locally, and split-tunneling is configured on the group policy pushed to the Easy VPN Remote. If both are true, checking this attribute automates the establishment of IPsec data tunnels. Otherwise, this attribute has no effect.

–

–

–

Group Name—Specifies the name of the group policy to use for authentication.

Group Password—Specifies the password to use with the specified group policy.

Confirm Password—Requires you to confirm the group password just entered.

X.509 Certificate—Specifies the use of an X.509 digital certificate, supplied by a Certificate

Authority, for authentication.

–

–

–

Select Trustpoint—Lets you select a trustpoint, which can be an IP address or a hostname, from the drop-down list. To define a trustpoint, click the link to Trustpoint(s) configuration at the bottom of this area.

Send certificate chain—Enables sending a certificate chain, not just the certificate itself. This action includes the root certificate and any subordinate CA certificates in the transmission.

User Settings—Configures user login information.

–

User Name—Configures the VPN username for the Easy VPN Remote connection. Xauth provides the capability of authenticating a user within IKE using TACACS+ or RADIUS. Xauth authenticates a user (in this case, the Easy VPN hardware client) using RADIUS or any of the other supported user authentication protocols. The Xauth username and password parameters are used when secure unit authentication is disabled and the server requests Xauth credentials.

If secure unit authentication is enabled, these parameters are ignored, and the adaptive security appliance prompts the user for a username and password.

–

User Password—Configures the VPN user password for the Easy VPN Remote connection.

Confirm Password—Requires you to confirm the user password just entered.

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Advanced Easy VPN Properties

•

Easy VPN Server To Be Added—Adds or removes an Easy VPN server. Any ASA or VPN 3000

Concentrator Series can act as a Easy VPN server. A server must be configured before a connection can be established. The adaptive security appliance supports IPv4 addresses, the names database, or

DNS names and resolves addresses in that order. The first server in the Easy VPN Server(s) list is the primary server. You can specify a maximum of ten backup servers in addition to the primary server.

–

–

Name or IP Address—The name or IP address of an Easy VPN server to add to the list.

Add—Moves the specified server to the Easy VPN Server(s) list.

–

–

Remove—Moves the selected server from the Easy VPN Server(s) list to the Name or IP

Address file. Once you do this, however, you cannot re-add the same address unless you re-enter the address in the Name or IP Address field.

Easy VPN Server(s)—Lists the configured Easy VPN servers in priority order.

–

Move Up/Move Down—Changes the position of a server in the Easy VPN Server(s) list. These buttons are available only when there is more than one server in the list.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—


Device Pass-Through

Certain devices like Cisco IP phones, printers, and the like are incapable of performing authentication, and therefore of participating in individual unit authentication. To accommodate these devices, the device pass-through feature, enabled by the MAC Exemption attributes, exempts devices with the specified MAC addresses from authentication when Individual User Authentication is enabled.

The first 24 bits of the MAC address indicate the manufacturer of the piece of equipment. The last 24 bits are the unit’s serial number in hexadecimal format.

Tunneled Management

When operating an ASA model 5505 device behind a NAT device, use the Tunneled Management attributes to specify how to configure device management— in the clear or through the tunnel—and specify the network or networks allowed to manage the Easy VPN Remote connection through the tunnel. The public address of the ASA 5505 is not accessible when behind the NAT device unless you add static NAT mappings on the NAT device.

When operating a Cisco ASA 5505 behind a NAT device, use the

vpnclient management

command to specify how to configure device management— with additional encryption or without it—and specify the hosts or networks to be granted administrative access. The public address of the ASA 5505 is not accessible when behind the NAT device unless you add static NAT mappings on the NAT device.

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Fields

•

MAC Exemption—Configures a set of MAC addresses and masks used for device pass-through for the Easy VPN Remote connection

–

MAC Address—Exempts the device with the specified MAC address from authentication. The format for specifying the MAC address this field uses three hex digits, separated by periods; for example, 45ab.ff36.9999.

•

–

–

–

–

MAC Mask—The format for specifying the MAC mask in this field uses three hex digits, separated by periods; for example, the MAC mask ffff.ffff.ffff matches just the specified MAC address. A MAC mask of all zeroes matches no MAC address, and a MAC mask of ffff.ff00.0000 matches all devices made by the same manufacturer.

Add—Adds the specified MAC address and mask pair to the MAC Address/Mask list.

–

Remove—Moves the selected MAC address and mask pair from the MAC Address/MAC list to the individual MAC Address and MAC Mask fields.

Tunneled Management—Configures IPsec encryption for device management and specifies the network or networks allowed to manage the Easy VPN hardware client connection through the tunnel. Selecting Clear Tunneled Management merely removes that IPsec encryption level and does not affect any other encryption, such as SSH or https, that exists on the connection.

Enable Tunneled Management—Adds a layer of IPsec encryption to the SSH or HTTPS encryption already present in the management tunnel.

Clear Tunneled Management—Uses the encryption already present in the management tunnel, without additional encryption.

•

–

–

IP Address— Specifies the IP address of the host or network to which you want to grant administrative access to the Easy VPN hardware client through the VPN tunnel. You can individually add one or more IP addresses and their respective network masks.

Mask—Specifies the network mask for the corresponding IP address.

–

–

–

Add—Moves the specified IP address and mask to the IP Address/Mask list.

Remove—Moves the selected IP address and mask pair from the IP Address/Mask list to the individual IP Address and Mask fields in this area.

–

IP Address/Mask—Lists the configured IP address and mask pairs to be operated on by the

Enable or Clear functions in this area.

IPsec Over TCP—Configure the Easy VPN Remote connection to use TCP-encapsulated IPsec.

Enable—Enables IPsec over TCP.

Note

Choose Configuration > VPN > IPsec > Pre-Fragmentation, double-click the outside interface, and set the DF Bit Setting Policy to Clear if you configure the Easy VPN Remote connection to use TCP-encapsulated IPsec. The Clear setting lets the adaptive security appliance send large packets.

•

–

Enter Port Number—Specifies the port number to use for the IPsec over TCP connection.

Server Certificate—Configures the Easy VPN Remote connection to accept only connections to

Easy VPN servers with the specific certificates specified by the certificate map. Use this parameter to enable Easy VPN server certificate filtering. To define a certificate map, go to Configuration >

VPN > IKE > Certificate Group Matching > Rules.

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Modes



Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—


AnyConnect Essentials is a separately licensed SSL VPN client, entirely configured on the adaptive security appliance, that provides the full AnyConnect capability, with the following exceptions:

•

No CSD (including HostScan/Vault/Cache Cleaner)

•

•

No clientless SSL VPN

Optional Windows Mobile Support (requires AnyConnect for Windows Mobile license)

The AnyConnect Essentials client provides remote end users running Microsoft Windows Vista,

Windows Mobile, Windows XP or Windows 2000, Linux, or Macintosh OS X, with the benefits of a

Cisco SSL VPN client.

To enable AnyConnect Essentials, check the

Enable AnyConnect Essentials

check box on the

AnyConnect Essentials pane, which appears only if the AnyConnect Essentials license is installed on the adaptive security appliance.

When AnyConnect Essentials is enabled, AnyConnect clients use Essentials mode, and clientless SSL

VPN access is disabled. When AnyConnect Essentials is disabled, AnyConnect clients use the full

AnyConnect SSL VPN Client.

Note

The status information about the AnyConnect Essentials license on the Configuration > Device

Management > Licensing > Activation Key pane simply reflects whether the AnyConnect Essentials license is installed. This status is not affected by the setting of the Enable AnyConnect Essentials License check box.

AnyConnect Essentials mode cannot be enabled when active clientless sessions exist to the device. To view SSL VPN session details click the

Monitoring > VPN > VPN Sessions

link in the SSL VPN

Sessions section. This opens the Monitoring > VPN > VPN > VPN Statistics > Sessions pane. To see session details, choose

Filter By: Clientless SSL VPN

and click

Filter

. This displays session details.

To see how many clientless SSL VPN sessions are currently active, without showing session details, click

Check Number of Clientless SSL Sessions

. If the SSL VPN session count is zero, you can enable

AnyConnect Essentials.

Note

Secure Desktop does not work when AnyConnect Essentials is enabled. You can, however, disable

AnyConnect Essentials when you enable Secure Desktop.

Modes


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DTLS Settings

Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

DTLS Settings

Enabling Datagram Transport Layer Security (DTLS) allows the AnyConnect VPN client establishing an SSL VPN connection to use two simultaneous tunnels—an SSL tunnel and a DTLS tunnel. Using


If you do not enable DTLS, AnyConnect client users establishing SSL VPN connections connect with an SSL VPN tunnel only.

Fields

•

Interface—Displays a list of interfaces on the adaptive security appliance.

•

•

DTLS Enabled—Click to enable DTLS connections with the AnyConnect client on the interfaces.

UDP Port (default 443)—(Optional) Specify a separate UDP port for DTLS connections.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

SSL VPN Client Settings

The Cisco AnyConnect VPN client provides secure SSL connections to the adaptive security appliance for remote users. The client gives remote users the benefits of an SSL VPN client without the need for network administrators to install and configure clients on remote computers.

Without a previously-installed client, remote users enter the IP address in their browser of an interface configured to accept SSL VPN connections. Unless the adaptive security appliance is configured to redirect http:// requests to https://, users must enter the URL in the form https://<

address

>.

If you need to redirect http:// requests to https://, go to

Configuration > Remote Access VPN >

Advanced

, then click

HTTP Redirect

. Choose the interface you want to redirect, then click

Edit

to display the Edit HTTP/HTTPS Settings dialog box. Check the

Redirect HTTP to HTTPS

check box, and change the HTTP Port value, if necessary. Click

OK

to close this dialog box, then click

Apply


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After entering the URL, the browser connects to that interface and displays the login screen. If the user satisfies the login and authentication, and the adaptive security appliance identifies the user as requiring the client, it downloads the client that matches the operating system of the remote computer. After downloading, the client installs and configures itself, establishes a secure SSL connection and either remains or uninstalls itself (depending on the adaptive security appliance configuration) when the connection terminates.

In the case of a previously installed client, when the user authenticates, the adaptive security appliance examines the revision of the client, and upgrades the client as necessary.

When the client negotiates an SSL VPN connection with the adaptive security appliance, it connects using Transport Layer Security (TLS), and optionally, Datagram Transport Layer Security (DTLS).


The AnyConnect client can be downloaded from the adaptive security appliance, or it can be installed manually on the remote PC by the system administrator. For more information about installing the client manually, see the


.

The adaptive security appliance downloads the client based on the group policy or local user policy attributes. You can configure the adaptive security appliance to automatically download the client, or you can configure it to prompt the remote user about whether to download the client. In the latter case, if the user does not respond, you can configure the adaptive security appliance to either download the client after a timeout period or present the login page.

Fields

•

SSL VPN Client Images table—Displays the package files specified as SSL VPN client images, and allows you to establish the order that the adaptive security appliance downloads the images to the remote PC.

–

–

Add—Displays the Add SSL VPN Client Image dialog box, where you can specify a file in flash memory as a client image file, or where you can browse flash memory for a file to specify as a client image. You can also upload a file from a local computer to the flash memory.

Replace—Displays the Replace SSL VPN Client Image dialog box, where you can specify a file in flash memory as an client image to replace an image highlighted in the SSL VPN Client

Images table. You can also upload a file from a local computer to the flash memory.

–

–

Delete—Deletes an image from the table. This does not delete the package file from flash.

Move Up and Move Down—changes the order in which the adaptive security appliance downloads the client images to the remote PC. It downloads the image at the top of the table first. Therefore, you should move the image used by the most commonly-encountered operating system to the top.

•

•

SSL VPN Client Profiles table—Displays the XML files specified as SSL VPN client profiles. These profiles display host information in the AnyConnect VPN Client user interface.

–

Add—Displays the Add SSL VPN Client Profiles dialog box, where you can specify a file in flash memory as a profile, or where you can browse flash memory for a file to specify as a profile. You can also upload a file from a local computer to the flash memory.

–

–

Edit—Displays the Edit SSL VPN Client Profiles dialog box, where you can specify a file in flash memory as a profile to replace a profile highlighted in the SSL VPN Client Profiles table.

You can also upload a file from a local computer to the flash memory.

Delete—Deletes a profile from the table. This does not delete the XML file from flash.

Cache File System—The security appliance expands SSL VPN client and CSD images in cache memory. Adjust the size of cache memory to ensure the images have enough space to expand.

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Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—


Add/Replace SSL VPN Client Image

In this pane, you can specify a filename for a file on the adaptive security appliance flash memory that you want to add as an SSL VPN client image, or to replace an image already listed in the table. You can also browse the flash memory for a file to identify, or you can upload a file from a local computer.

Fields

•

Flash SVC Image—Specify the file in flash memory that you want to identify as an SSL VPN client image.

•

Browse Flash—Displays the Browse Flash dialog box where you can view all the files on flash memory.

•

•

Upload—Displays the Upload Image dialog box where you can upload a file from a local PC that you want to identify as an client image.

Regular expression to match user-agent—Specifies a string that the adaptive security appliance uses to match against the User-Agent string passed by the browser. For mobile users, you can decrease the connection time of the mobile device by using the feature

.

When the browser connects to the adaptive security appliance, it includes the User-Agent string in the HTTP header. When the adaptive security appliance receives the string, if the string matches an expression configured for an image, it immediately downloads that image without testing the other client images.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Upload Image

In this pane, you can specify the path of a file on the local computer or in flash memory of the security appliance that you want to identify as an SSL VPN client image. You can also browse the local computer or the flash memory of the security appliance for a file to identify.

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Fields

•

Local File Path—Identifies the filename of the file in on the local computer that you want to identify as an SSL VPN client image.

•

Browse Local Files—Displays the Select File Path dialog box where you can view all the files on local computer and where you can select a file to identify as a client image.

•

•

•

Flash File System Path—Identifies the filename of the file in the flash memory of the security appliance that you want to identify as an SSL VPN client image.

Browse Flash—Displays the Browse Flash Dialog dialog box where you can view all the files on flash memory of the security appliance and where you can choose a file to identify as a client image.

Upload File—Initiates the file upload.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit SSL VPN Client Profiles

In this pane you can specify the path of a file on the local computer or in flash memory of the adaptive security appliance that you want to identify as an SSL VPN client profile. These profiles display host information in the AnyConnect VPN client user interface. You can also browse the local computer or the flash memory of the security appliance for a file to identify.

Fields

•

Profile Name—Associates a name with the XML file that appears in the table. Provide any name that makes it easy for you to remember the hosts identified in the XML profile file.

•

Profile Package—Identifies the filename of the file in flash memory on the local computer that you want to identify as an SSL VPN client profile.

•

•

Browse Flash—Displays the Browse Flash Dialog dialog box where you can view all the files on flash memory of the security appliance and where you can choose a file to identify as a profile.


Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

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Bypass Interface Access List

Upload Package

In this pane, you can specify the path of a file on the local computer or in flash memory of the security appliance that you want to identify as an SSL VPN client profile. You can also browse the local computer or the flash memory of the security appliance for a file to identify.

Fields

•

Local File Path—Identifies the filename of the file in on the local computer that you want to identify as an SSL VPN client profile.

•

Browse Local Files—Displays the Select File Path dialog box where you can view all the files on local computer and where you can select a file to identify as a client profile.

•

•

•

Flash File System Path—Identifies the filename of the file in the flash memory of the security appliance that you want to identify as an client profile.

Browse Flash—Displays the Browse Flash dialog box where you can view all the files on flash memory of the security appliance and where you can choose a file to identify as a client profile.


Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—


You can require an access rule to apply to the local IP addresses by unchecking this check box. The access rule applies to the local IP address, and not to the original client IP address used before the VPN packet was decrypted.

•

Enable inbound IPSec sessions to bypass interface access-lists. Group policy and per-user authorization access lists still apply to the traffic—By default, the adaptive security appliance allows

VPN traffic to terminate on a adaptive security appliance interface; you do not need to allow IKE or

ESP (or other types of VPN packets) in an access rule. When this check box is checked, you also do not need an access rule for local IP addresses of decrypted VPN packets. Because the VPN tunnel was terminated successfully using VPN security mechanisms, this feature simplifies configuration and maximizes the adaptive security appliance performance without any security risks. (Group policy and per-user authorization access lists still apply to the traffic.)

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C H A P T E R

65


This chapter describes how to configure dynamic access policies. It includes the following sections.

•

Understanding VPN Access Policies

•

•

•

•

•

•

Add/Edit Dynamic Access Policies


Retrieving Active Directory Groups

Add/Edit Endpoint Attributes

Operator for Endpoint Category

DAP Examples

Understanding VPN Access Policies

VPN gateways operate in dynamic environments. Multiple variables can affect each VPN connection, for example, intranet configurations that frequently change, the various roles each user may inhabit within an organization, and logins from remote access sites with different configurations and levels of security. The task of authorizing users is much more complicated in a VPN environment than it is in a network with a static configuration.

Dynamic access policies (DAP) on the adaptive security appliance let you configure authorization that addresses these many variables. You create a dynamic access policy by setting a collection of access control attributes that you associate with a specific user tunnel or session. These attributes address issues of multiple group membership and endpoint security. That is, the adaptive security appliance grants access to a particular user for a particular session based on the policies you define. It generates a DAP at the time the user connects by selecting and/or aggregating attributes from one or more DAP records.

It selects these DAP records based on the endpoint security information of the remote device and the

AAA authorization information for the authenticated user. It then applies the DAP record to the user tunnel or session.

The DAP system includes the following components that require your attention:

•

DAP Selection Configuration File—A text file containing criteria that the adaptive security appliance uses for selecting and applying DAP records during session establishment. Stored on the adaptive security appliance. You can use ASDM to modify it and upload it to the adaptive security appliance in XML data format. DAP selection configuration files include all of the attributes that you configure. These can include AAA attributes, endpoint attributes, and access policies as configured in network and web-type ACL filter, port forwarding and URL lists,


65-1 OL-20339-01

Chapter 65 Configuring Dynamic Access Policies


•

Refer to the

Dynamic Access Deployment Guide

( http://supportwiki.cisco.com/ViewWiki/index.php/ASA_8.x_Dynamic_Access_Policies_%28DAP%2

9_Deployment_Guide ) for additional information.

For more information about Dynamic Access Policies, see the following sections.

•

DfltAccess Policy—Always the last entry in the DAP summary table, always with a priority of 0.

You can configure Access Policy attributes for the default access policy, but it does not contain—and you cannot configure—AAA or endpoint attributes. You cannot delete the DfltAccessPolicy, and it must be the last entry in the summary table.

•

•

•

•

•

DAP Support for Remote Access Connection Types

DAP and AAA

DAP and Endpoint Security

DAP Connection Sequence

Test Dynamic Access Policies

DAP Examples

65-2


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Figure 65-1 shows the Dynamic Access Policies pane.

Figure 65-1 Dynamic Access Policies ASDM pane


OL-20339-01

To configure dynamic access policies, in the Configuration > Remote Access VPN > Network (Client)

Access or Clientless SSL VPN Access > Dynamic Access Policies pane in ASDM, perform the following steps:

Step 1

To include certain antivirus, antispyware, or personal firewall endpoint attributes, click the CSD configuration link near the top of the pane. Then enable Cisco Secure Desktop

and

Host Scan extensions.

This link does not display if you have previously enabled both of these features.

If you enable Cisco Secure Desktop, but do not enable Host Scan extensions, when you apply your changes ASDM includes a link to enable Host Scan configuration .


65-3



Step 2

Step 3

To create a new dynamic access policy, click

Add

. To modify an existing policy, click

Edit

.

To test already configured polices, click

Test Dynamic Access Policies

.

•

•

•

Fields

•

Priority—Displays the priority of the DAP record. The adaptive security appliance uses this value to logically sequence the access lists when aggregating the network and web-type ACLs from multiple DAP records. The adaptive security appliance orders the records from highest to lowest priority number, with lowest at the bottom of the table. Higher numbers have a higher priority, that is a DAP record with a value of 4 has a higher priority than a record with a value of 2. You cannot manually sort them.

•

Name—Displays the name of the DAP record.

•

Network ACL List—Displays the name of the firewall access list that applies to the session.

Web-Type ACL List—Displays the name of the SSL VPN access list that applies to the session.

Description—Describes the purpose of the DAP record.

Test Dynamic Access Policies button—Click to test already configured DAP records.

Modes


Firewall Mode

Routed

•


•


Multiple

•

Context

—

System

—

DAP Support for Remote Access Connection Types

The DAP system supports the following remote access methods:

•

•

•

•

IPsec VPN

Clientless (browser-based) SSLVPN

Cisco AnyConnect SSL VPN

PIX cut-through proxy (posture assessment not available)

DAP and AAA

DAP complements AAA services. It provides a limited set of authorization attributes that can override those AAA provides. The adaptive security appliance selects DAP records based on the AAA authorization information for the user and posture assessment information for the session. The adaptive security appliance can select multiple DAP records depending on this information, which it then aggregates to create DAP authorization attributes.

You can specify AAA attributes from the Cisco AAA attribute hierarchy, or from the full set of response attributes that the adaptive security appliance receives from a RADIUS or LDAP server. For more information about DAP and AAA, see the section,


.


65-4 OL-20339-01



AAA Attribute Definitions

Table 65-1

defines the AAA selection attribute names that are available for DAP use. The Attribute

Name field shows you how to enter each attribute name in a Lua logical expression, which you might do in the Advanced section of the Add/Edit Dynamic Access Policy pane.

Table 65-1

Attribute

Type

AAA Selection Attributes for DAP Use

Attribute Name Source Value

Max String

Length Description

Cisco aaa.cisco.grouppolicy AAA aaa.cisco.ipaddress

aaa.cisco.tunnelgroup AAA aaa.cisco.username

AAA

AAA string number string string

64

-

64

64

Group policy name on the adaptive security appliance or sent from a Radius/LDAP server as the IETF-CLass (25) attribute

Assigned IP address for full tunnel VPN clients (IPsec, L2TP/IPsec, SSL VPN

AnyConnect)

Connection profile (tunnel group) name

Name of the authenticated user (applies if using Local authentication/authorization)

LDAP aaa.ldap.<

label

> LDAP string

RADIUS aaa.radius.<number> RADIUS string

128

128

LDAP attribute value pair

Radius attribute value pair

See Security Appliance Supported RADIUS Attributes and Values for a table that lists RADIUS attributes that the security appliance supports.

DAP and Endpoint Security

The adaptive security appliance obtains endpoint security attributes by using posture assessment methods that you configure. These include Cisco Secure Desktop and NAC. For details, see the Cisco

Secure Desktop section of ASDM.

Table 65-2

identifies each of the remote access protocols DAP supports, the posture assessment tools available for that method, and the information that tool provides.

Table 65-2 DAP Posture Assessment

Remote Access Protocol Cisco Secure Desktop

IPsec VPN

Cisco AnyConnect VPN X

Returns files information, registry key values, running processes, operating system

—

1

Clientless VPN

PIX Cut-through Proxy

X

—

1.

— indicates no; X indicates yes.

Host Scan

X

X

Returns antivirus, antispyware, and personal firewall software information

—

—

NAC

Cisco NAC

Appliance

Returns NAC status

X

X

—

—

Returns VLAN

Type and

VLAN IDs

X

X

—

—

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65-5



Endpoint Attribute Definitions

Table 65-3 defines the endpoint selection attribute names that are available for DAP use.The Attribute

Name field shows you how to enter each attribute name in a Lua logical expression, which you might do in the Advanced area in the Add/Edit Dynamic Access Policy pane. The

label

variable identifies the application, filename, process, or registry entry.

Table 65-3 Endpoint Attribute Definitions

Attribute Type Attribute Name

Antispyware

(Requires

Cisco Secure

Desktop)

Antivirus

(Requires

Cisco Secure

Desktop)

Application endpoint.as[" endpoint.as[" endpoint.as["

label label label

"].exists

"].version

"].description

endpoint.as["

label

"].lastupdate

endpoint.av[" endpoint.av[" endpoint.av[" endpoint.av["

label label label label

"].exists

"].version

"].description

"].lastupdate

endpoint.application.clienttype

Source

Host Scan

Host Scan

Application

Value

Max

String


true string

—

32 string 128 integer — true string string integer string

—

32

128

—

—

Antispyware program exists

Version

Antispyware description

Seconds since update of antispyware definitions

Antivirus program exists

Version

Antivirus description

Seconds since update of antivirus definitions

Client type:

CLIENTLESS

File Secure

Desktop true integer

—

—

ANYCONNECT

IPSEC

L2TP

The files exists

Seconds since file was last modified

NAC

Operating

System

Personal firewall

(Requires

Secure

Desktop)

Policy

Process endpoint.file["

label

"].exists

endpoint.file["

label

"].lastmodifi

ed endpoint.file["

label

"].crc.32

endpoint.nac.status

endpoint.os.version

endpoint.os.servicepack

endpoint.fw["

label

"].exists

endpoint.fw["

label

"].version

endpoint.fw["

label

"].description

NAC

Secure

Desktop

Host Scan endpoint.policy.location

Secure

Desktop endpoint.process["

label

"].exists

Secure endpoint.process["

label

"].path

Desktop integer string string

—

—

32 integer — true — string string string true string

32

128

64

—

255

CRC32 hash of the file

User defined status string

Operating system

Service pack for Windows

The personal firewall exists

Version

Personal firewall description

Location value from Cisco Secure

Desktop

The process exists

Full path of the process

65-6


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Table 65-3 Endpoint Attribute Definitions (continued)

Attribute Type Attribute Name

Registry endpoint.registry["

label

"].type

Source

Secure

Desktop

VLAN endpoint.registry["

label

"].value

endoint.vlan.type

CNA

Value

dword string

string string

Max

String


— dword

255

—

Value of the registry entry

VLAN type:

ACCESS

AUTH

ERROR

GUEST

QUARANTINE

ERROR

STATIC

TIMEOUT

DAP and AntiVirus, AntiSpyware, and Personal Firewall Programs

The security appliance uses a DAP policy when the user attributes matches the configured AAA and endpoint attributes. The Prelogin Assessment and Host Scan modules of Cisco Secure Desktop return information to the security appliance about the configured endpoint attributes, and the DAP subsystem uses that information to select a DAP record that matches the values of those attributes.

Most, but not all, antivirus, antispyware, and personal firewall programs support active scan, which means that the programs are memory-resident, and therefore always running. Host Scan checks to see if an endpoint has a program installed, and if it is memory-resident as follows:

•

If the installed program does not support active scan, Host Scan reports the presence of the software.

The DAP system selects DAP records that specify the program.

•

•

If the installed program does support active scan, and active scan is enabled for the program, Host

Scan reports the presence of the software. Again the security appliance selects DAP records that specify the program.

If the installed program does support active scan and active scan is disabled for the program, Host

Scan ignores the presence of the software. The security appliance does not select DAP records that specify the program. Further, the output of the

debug trace

command, which includes a lot of information about DAP, does not indicate the program presence, even though it is installed.

DAP Connection Sequence

The following sequence outlines a typical remote access connection establishment.

1.

A remote client attempts a VPN connection.

2.

3.

4.

The adaptive security appliance performs posture assessment, using configured NAC and Cisco

Secure Desktop Host Scan values.

The adaptive security appliance authenticates the user via AAA. The AAA server also returns authorization attributes for the user.

The adaptive security appliance applies AAA authorization attributes to the session, and establishes the VPN tunnel.


OL-20339-01 65-7



5.

6.

7.

The adaptive security appliance selects DAP records based on the user AAA authorization information and the session posture assessment information.

The adaptive security appliance aggregates DAP attributes from the selected DAP records, and they become the DAP policy.

The adaptive security appliance applies the DAP policy to the session.

Test Dynamic Access Policies

Figure 65-2

shows the Test Dynamic Access Policies pane.

Figure 65-2 Test Dynamic Access Policies Pane

This pane lets you test the retrieval of the set of DAP records configured on the device by specifying authorization attribute value pairs. To specify these pairs, use the Add/Edit buttons associated with the

AAA Attribute and Endpoint Attribute tables. The dialogs that display when you click these Add/Edit buttons are similar to those in the Add/Edit AAA Attributes and Add/Edit Endpoint Attributes dialog boxes.

65-8


OL-20339-01



When you enter attribute value pairs and click the “Test” button, the DAP subsystem on the device references these values when evaluating the AAA and endpoint selection attributes for each record. The results display in the “Test Results” text area.

Fields

•

Selection Criteria—Determine the AAA and endpoint attributes to test for dynamic access policy retrieval.

•

AAA Attributes

–

AAA Attribute—Identifies the AAA attribute.

–

–

Operation Value—Identifies the attribute as =/!= to the given value.

Add/Edit—Click to add or edit a AAA attribute.

•

Endpoint Attributes—Identifies the endpoint attribute.

–

Endpoint ID—Provides the endpoint attribute ID.

–

–

Name/Operation/Value—

Add/Edit/Delete—Click to add, edit or delete and endpoint attribute.

•

•

•

Test Result—Displays the result of the test.

Test—Click to test the retrieval of the policies you have set.

Close—Click to close the pane.

Modes


Firewall Mode

Routed

•


•


Multiple

•

Context

—

System

—

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65-9


Add/Edit Dynamic Access Policies

Figure 65-3 Add/Edit Dynamic Access Policies Pane


65-10

To add or edit a dynamic access policy, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

At the top of the Add/Edit Dynamic Access Policy pane, provide a name (required) and a description

(optional) of this dynamic access policy.

In the Priority field, set a priority for the dynamic access policy. The adaptive security appliance applies access policies in the order you set here, highest number having the highest priority. In the case of DAP records with the same priority setting and conflicting ACL rules, the most restrictive rule applies.

In the Add/Edit AAA Attributes field, use the ANY/ALL/NONE drop-down list (unlabeled) to choose whether a user must have any, all, or none of the AAA attribute values you configure to use this dynamic access policy.

To Set AAA attributes, click

Add/Edit

in the AAA Attributes field.

Before you set endpoint attributes, configure CSD Host Scan.

To set endpoint security attributes, click

Add/Edit

in the Endpoint ID field.

You can create multiple instances of each type of endpoint attribute. For each of these types, you need to decide whether the DAP policy should require that the user have all instances of a type (Match all =

AND) or only one of them (Match Any = OR). To set this value for each of the end point attributes, click the

Logical Op.

button.


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OL-20339-01

Step 8

Step 9

In the Advanced field you can enter one or more logical expressions to set AAA or endpoint attributes other than what is possible in the AAA and Endpoint areas above.

To configure network and webtype ACLs, file browsing, file server entry, HTTP proxy, URL entry, port forwarding lists and URL lists, set values in the Access Policy Attributes fields.

Fields

•

Policy Name—A string of 4 through 32 characters, no spaces allowed.

•

Description—(Optional) Describes the purpose of the DAP record. Maximum 80 characters.

•

•

Priority—Sets the priority of the DAP. The security appliance applies access policies in the order you set here, highest number having the highest priority. Values of 0 to 2147483647 are valid.

Default = 0.

ANY/ALL/NONE drop-down list—Set to require that user authorization attributes match any, all, or none of the values in the AAA attributes you are configuring, as well as satisfying every endpoint attribute. Duplicate entries are not allowed. If you configure a DAP record with no AAA or endpoint attributes, the adaptive security appliance always selects it since all selection criteria are satisfied.

•

•

AAA Attributes—Displays the configured AAA attributes.

–

Attribute—Displays the name of the AAA attribute.

–

–

Operation/Value—=/!=

Add/Edit/Delete—Click to add, edit, or delete the highlighted AAA attribute.

Endpoint Attributes—Displays the configured endpoint attributes

–

Endpoint ID—Identifies endpoint attributes.

–

–

Name/Operation/Value—Summarizes configured values for each endpoint attribute.

Add/Edit/Delete—Click to add, edit, or delete the highlighted endpoint attribute.

Note

Cisco Secure Desktop provides the adaptive security appliance with all endpoint attributes except Application and NAC. To configure all other endpoint attributes, you must first enable

Cisco Secure Desktop, and configure the relevant endpoint attributes there as well.

–

–

–

–

–

Logical Op.—You can create multiple instances of each type of endpoint attribute. Click to configure whether the DAP policy should require that the user have all instances of a type

(Match all = AND) or only one of them (Match Any = OR). Be aware that for some endpoint attributes, for example OS, it can never happen that a user would have more than one instance of the attribute.

Advanced—Click to set additional attributes for the dynamic access policy. Be aware that this is an advanced feature that requires knowledge of Lua.

AND/OR—Click to define the relationship between the basic selection rules and the logical expressions you enter here, that is, whether the new attributes add to or substitute for the AAA and endpoint attributes already set. The default is AND.

Logical Expressions—You can configure multiple instances of each type of endpoint attribute.

Enter free-form Lua text that defines new AAA and/or endpoint selection attributes. ASDM does not validate text that you enter here; it just copies this text to the DAP XML file, and the adaptive security appliance processes it, discarding any expressions it cannot parse.

Guide—Click to display online help for creating these logical operations.


65-11



•

•

Access Policy Attributes—These tabs let you set attributes for network and webtype ACL filters, file access, HTTP proxy, URL entry and lists, port forwarding, and clientless SSL VPN access methods. Attribute values that you configure here override authorization values in the AAA system, including those in existing user, group, tunnel group, and default group records.

Action Tab—Specifies special processing to apply to a specific connection or session.

–

Continue—(Default) Click to apply access policy attributes to the session.

–

Quarantine—Through the use of quarantine, you can restrict a particular client who already has an established tunnel through a VPN. ASA applies restricted ACLs to a session to form a restricted group, based on the selected DAP record. When an endpoint is not compliant with an administratively defined policy, the user can still access services for remediation (such as updating the antivirus and so on), but restrictions are placed upon the user. After the remediation occurs, the user can reconnect, which invokes a new posture assessment. If this assessment passes, the user connects.

Note

This parameter requires a release of the Cisco IronPort Web Security appliance that provides AnyConnect Secure Mobility licensing support for the Cisco AnyConnect secure mobility client. It also requires an AnyConnect release that supports AnyConnect

Secure Mobility features.

–

–

Terminate—Click to terminate the session.

User Message—Enter a text message to display on the portal page when this DAP record is selected. Maximum 128 characters. A user message displays as a yellow orb. When a user logs on it blinks three times to attract attention, and then it is still. If several DAP records are selected, and each of them has a user message, all of the user messages display.

Note

You can include in such messages URLs or other embedded text, which require that you use the correct HTML tags.

For example: All contractors please read <a href='http://wwwin.abc.com/procedure.html'>

Instructions</a> for the procedure to upgrade your antivirus software.

•

•

Network ACL Filters Tab—Lets you select and configure network ACLs to apply to this DAP record. An ACL for DAP can contain permit or deny rules, but not both. If an ACL contains both permit and deny rules, the adaptive security appliance rejects it.

–

Network ACL drop-down list—Select already configured network ACLs to add to this DAP record. Only ACLs having all permit or all deny rules are eligible, and these are the only ACLs that display here.

–

–

Manage...—Click to add, edit, and delete network ACLs.

Network ACL list—Displays the network ACLs for this DAP record.

–

Add—Click to add the selected network ACL from the drop-down list to the Network ACLs list on the right.

–

Delete—Click to delete a highlighted network ACL from the Network ACLs list. You cannot delete an ACL from the adaptive security appliance unless you first delete it from DAP records.

Web-Type ACL Filters Tab—Lets you select and configure web-type ACLs to apply to this DAP record. An ACL for DAP can contain only permit or deny rules. If an ACL contains both permit and deny rules, the adaptive security appliance rejects it.

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•

–

–

–

Web-Type ACL drop-down list—Select already configured web-type ACLs to add to this DAP record. Only ACLs having all permit or all deny rules are eligible, and these are the only ACLs that display here.

Manage...—Click to add, edit, and delete web-type ACLs.

Web-Type ACL list—Displays the web-type ACLs for this DAP record.

–

–

Add—Click to add the selected web-type ACL from the drop-down list to the Web-Type ACLs list on the right.

Delete—Click to delete a web-type ACL from the Web-Type ACLs list. You cannot delete an

ACL from the adaptive security appliance unless you first delete it from DAP records.

Functions Tab—Lets you configure file server entry and browsing, HTTP proxy, and URL entry for the DAP record.

–

File Server Browsing—Enables or disables CIFS browsing for file servers or shared features.

Note

Browsing requires NBNS (Master Browser or WINS). If that fails or is not configured, we use DNS.

The CIFS browse feature does not support internationalization.

–

–

–

File Server Entry—Lets or prohibits a user from entering file server paths and names on the portal page. When enabled, places the file server entry drawer on the portal page. Users can enter pathnames to Windows files directly. They can download, edit, delete, rename, and move files. They can also add files and folders. Shares must also be configured for user access on the applicable Windows servers. Users might have to be authenticated before accessing files, depending on network requirements.

HTTP Proxy—Affects the forwarding of an HTTP applet proxy to the client. The proxy is useful for technologies that interfere with proper content transformation, such as Java, ActiveX, and

Flash. It bypasses mangling while ensuring the continued use of the security appliance. The forwarded proxy modifies the browser’s old proxy configuration automatically and redirects all

HTTP and HTTPS requests to the new proxy configuration. It supports virtually all client side technologies, including HTML, CSS, JavaScript, VBScript, ActiveX, and Java. The only browser it supports is Microsoft Internet Explorer.

URL Entry—Allows or prevents a user from entering HTTP/HTTPS URLs on the portal page.

If this feature is enabled, users can enter web addresses in the URL entry box, and use clientless

SSL VPN to access those websites.

Using SSL VPN does not ensure that communication with every site is secure. SSL VPN ensures the security of data transmission between the remote user PC or workstation and the adaptive security appliance on the corporate network. If a user then accesses a non-HTTPS web resource

(located on the Internet or on the internal network), the communication from the corporate adaptive security appliance to the destination web server is not secured.

In a clientless VPN connection, the adaptive security appliance acts as a proxy between the end user web browser and target web servers. When a user connects to an SSL-enabled web server, the adaptive security appliance establishes a secure connection and validates the server SSL certificate.

The end user browser never receives the presented certificate, so therefore cannot examine and validate the certificate. The current implementation of SSL VPN does not permit communication with sites that present expired certificates. Neither does the adaptive security appliance perform trusted CA certificate validation. Therefore, users cannot analyze the certificate an SSL-enabled web-server presents before communicating with it.

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•

To limit Internet access for users, choose Disable for the URL Entry field. This prevents SSL VPN users from surfing the web during a clientless VPN connection.

–

–

Unchanged—(default) Click to use values from the group policy that applies to this session.

Enable/Disable—Click to enable or disable the feature.

–

Auto-start—Click to enable HTTP proxy and to have the DAP record automatically start the applets associated with these features.

Port Forwarding Lists Tab—Lets you select and configure port forwarding lists for user sessions.

Port Forwarding provides access for remote users in the group to client/server applications that communicate over known, fixed TCP/IP ports. Remote users can use client applications that are installed on their local PC and securely access a remote server that supports that application. Cisco has tested the following applications: Windows Terminal Services, Telnet, Secure FTP (FTP over

SSH), Perforce, Outlook Express, and Lotus Notes. Other TCP-based applications may also work, but Cisco has not tested them.

Note

Port Forwarding does not work with some SSL/TLS versions.

Caution

Make sure Sun Microsystems Java Runtime Environment (JRE) 1.4+ is installed on the remote computers to support port forwarding (application access) and digital certificates.

•

–

–

–

Port Forwarding—Select an option for the port forwarding lists that apply to this DAP record.

The other attributes in this field are enabled only when you set Port Forwarding to Enable or

Auto-start.

Unchanged—Click to remove the attributes from the running configuration.

Enable/Disable—Click to enable or disable port forwarding.

–

Auto-start—Click to enable port forwarding, and to have the DAP record automatically start the port forwarding applets associated with its port forwarding lists.

–

–

Port Forwarding List drop-down list—Select already configured port forwarding lists to add to the DAP record.

New...—Click to configure new port forwarding lists.

–

–

Port Forwarding Lists (unlabeled)—Displays the port forwarding lists for the DAP record.

Add—Click to add the selected port forwarding list from the drop-down list to the Port

Forwarding list on the right.

–

Delete—Click to delete selected port forwarding list from the Port Forwarding list. You cannot delete a port forwarding list from the adaptive security appliance unless you first delete it from

DAP records.

Bookmarks—Lets you select and configure bookmarks for certain user session URLs.

–

–

Enable bookmarks—Click to enable. When unchecked, no bookmarks display in the portal page for the connection.

Bookmark drop-down list—select already configured bookmarks to add to the DAP record.

–

–

Manage...—Click to add, import, export, and delete bookmarks.

Bookmarks (unlabeled)—Displays the URL lists for the DAP record.

–

Add—Click to add the selected bookmark from the drop-down list to the URL area on the right.

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•

•

–

–

Delete—Click to delete the selected bookmark from the URL list area. You cannot delete a bookmark from the adaptive security appliance unless you first delete it from DAP records.

Access Method Tab—Lets you configure the type of remote access permitted.

–

Unchanged—Continue with the current remote access method.

–

AnyConnect Client—Connect using the Cisco AnyConnect VPN Client.

Web-Portal—Connect with clientless VPN.

–

–

Both-default-Web-Portal—Connect via either clientless or the AnyConnect client, with a default of clientless.

Both-default-AnyConnect Client—Connect via either clientless or the AnyConnect client, with a default of AnyConnect.

AnyConnect Tab—Lets you choose the status of the Always-on VPN flag.

–

Always-On VPN for AnyConnect client—Determine if the always-on VPN flag setting in the

AnyConnect service profile is unchanged, disabled, or if the AnyConnect profile setting should be used.

Note

This parameter requires a release of the Cisco IronPort Web Security appliance that provides Secure Mobility Solution licensing support for the Cisco AnyConnect VPN client. It also requires an AnyConnect release that supports “Secure Mobility Solution” features. Refer to the


for additional information.

Modes


Firewall Mode

Routed



Multiple

Context

• • •

—

System

—

Add/Edit AAA Attributes

Figure 65-4 shows the Add AAA Attribute dialog box.

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Figure 65-4 Add AAA Attribute Dialog Box


To configure AAA attributes as selection criteria for DAP records, in the Add/Edit AAA Attributes dialog box, set the Cisco, LDAP, or RADIUS attributes that you want to use. You can set these attributes either to = or != the value you enter. There is no limit for the number of AAA attributes for each DAP record. For detailed information about AAA attributes, see

AAA Attribute Definitions .

Fields

AAA Attributes Type—Use the drop-down list to select Cisco, LDAP or RADIUS attributes:

•

Cisco—Refers to user authorization attributes that are stored in the AAA hierarchical model. You can specify a small subset of these attributes for the AAA selection attributes in the DAP record.These include:

–

Group Policy —The group policy name associated with the VPN user session. Can be set locally on the security appliance or sent from a RADIUS/LDAP server as the IETF-Class (25) attribute.

Maximum 64 characters.

–

–

IP Address—The assigned IP address for full tunnel VPN clients (IPsec, L2TP/IPsec, SSL VPN

AnyConnect). Does not apply to Clientless SSL VPN, since there is no address assignment for clientless sessions

.

Connection Profile—The connection or tunnel group name. Maximum 64 characters.

•

–

–

Username—The username of the authenticated user. Maximum 64 characters. Applies if you are using Local, RADIUS, LDAP authentication/authorization or any other authentication type (for example, RSA/SDI), NT Domain, etc).

=/!=—Equal to/Not equal to.

LDAP—The LDAP client (security appliance) stores all native LDAP response attribute value pairs in a database associated with the AAA session for the user. The LDAP client writes the response attributes to the database in the order in which it receives them. It discards all subsequent attributes with that name. This scenario might occur when a user record and a group record are both read from the LDAP server. The user record attributes are read first, and always have priority over group record attributes.

To support Active Directory group membership, the AAA LDAP client provides special handling of the LDAP memberOf response attribute. The AD memberOf attribute specifies the DN string of a group record in AD. The name of the group is the first CN value in the DN string. The LDAP client extracts the group name from the DN string and stores it as the AAA memberOf attribute, and in the response attribute database as the LDAP memberOf attribute. If there are additional memberOf

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attributes in the LDAP response message, then the group name is extracted from those attributes and is combined with the earlier AAA memberOf attribute to form a comma separated string of group names, also updated in the response attribute database.

In the case where the VPN remote access session to an LDAP authentication/authorization server returns the following three Active directory groups (memberOf enumerations): cn=Engineering,ou=People,dc=company,dc=com cn=Employees,ou=People,dc=company,dc=com cn=EastCoastast,ou=People,dc=company,dc=com the ASA processes three Active Directory groups: Engineering, Employees, and EastCoast which could be used in any combination as aaa.ldap selection criteria.

LDAP attributes consist of an attribute name and attribute value pair in the DAP record. The LDAP attribute name is syntax/case sensitive. If for example you specify LDAP attribute Department instead of what the AD server returns as department, the DAP record will not match based on this attribute setting.

Note

To enter multiple values in the Value field, use the semicolon (;) as the delimiter. For example: eng;sale; cn=Audgen VPN,ou=USERS,o=OAG

•

RADIUS—The RADIUS client stores all native RADIUS response attribute value pairs in a database associated with the AAA session for the user. The RADIUS client writes the response attributes to the database in the order in which it receives them. It discards all subsequent attributes with that name. This scenario might occur when a user record and a group record are both read from the RADIUS server. The user record attributes are read first, and always have priority over group record attributes.

RADIUS attributes consist of an attribute number and attribute value pair in the DAP record. See

Security Appliance Supported RADIUS Attributes and Values for a table that lists RADIUS attributes that the security appliance supports.

Note

For RADIUS attributes, DAP defines the Attribute ID = 4096 + RADIUS ID.

For example:

The RADIUS attribute "Access Hours" has a Radius ID = 1, therefore DAP attribute value =

4096 + 1 = 4097.

The RADIUS attribute "Member Of" has a Radius ID = 146, therefore DAP attribute value =

4096 + 146 = 4242.

•

LDAP and RADIUS attributes include:

–

Attribute ID—Names/numbers the attribute. Maximum 64 characters.

–

Value—The attribute name (LDAP) or number (RADIUS).

To enter multiple values in the Value field, use the semicolon (;) as the delimiter. For example: eng;sale; cn=Audgen VPN,ou=USERS,o=OAG


65-17



–

=/!=—Equal to/Not equal to.

•

LDAP includes the Get AD Groups button. This button queries the Active Directory LDAP server for the list of groups the user belong to (memberOf enumerations). It retrieves the AD groups using the CLI show-ad-groups command in the background

The

show ad-groups

command applies only to Active Directory servers using LDAP. Use this command to display AD groups that you can use for dynamic access policy AAA selection criteria.

The default time that the adaptive security appliance waits for a response from the server is 10 seconds.

You can adjust this time using the

group-search-timeout

command in aaa-server host configuration mode.

Note

If the Active Directory server has a large number of groups, the output of the

show ad-groups

command might be truncated based on limitations to the amount of data the server can fit into a response packet.

To avoid this problem, use the filter option to reduce the number of groups reported by the server.

Modes


Firewall Mode

Routed

•


•


Multiple

•

Context

—

System

—

Retrieving Active Directory Groups

Figure 65-5

shows the Retrieve AD Groups from Selected AD Server Group pane.

Figure 65-5 Retrieve AD Groups Dialog Box

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You can query an Active Directory server for available AD groups in this pane. This feature applies only to Active Directory servers using LDAP. Use the group information to specify dynamic access policy

AAA selection criteria.

You can change the level in the Active Directory hierarchy where the search begins by changing the

Group Base DN in the Edit AAA Server pane. You can also change the time that the adaptive security appliance waits for a response from the server in the window. To configure these features, choose

Configuration > Remote Access VPN > AAA/Local Users > AAA Server Groups > Edit AAA Server.

Note

If the Active Directory server has a large number of groups, the list of AD groups retrieved may be truncated based on limitations of the amount of data the server can fit into a response packet. To avoid this problem, use the filter feature to reduce the number of groups reported by the server.

Fields

AD Server Group—The name of the AAA server group to retrieve AD groups.

Filter By—Specify a group or the partial name of a group to reduce the groups displayed.

Group Name—A list of AD groups retrieved from the server.

Modes


Firewall Mode

Routed

•


•


Multiple

•

Context

—

System

—

Add/Edit Endpoint Attributes

Figure 65-6 shows the Add Endpoint Attributes dialog box.

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Figure 65-6 Add Endpoint Attributes Dialog Box


Endpoint attributes contain information about the endpoint system environment, posture assessment results, and applications. The adaptive security appliance dynamically generates a collection of endpoint attributes during session establishment, and stores these attributes in a database associated with the session. There is no limit for the number of endpoint attributes for each DAP record.

Each DAP record specifies the endpoint selection attributes that must be satisfied for the adaptive security appliance to select it. The adaptive security appliance selects only DAP records that satisfy every condition configured.

For detailed information about Endpoint attributes, see

Endpoint Attribute Definitions

.

To configure endpoint attributes as selection criteria for DAP records, in the Add/Edit Endpoint Attribute dialog box, set components. These components change according to the attribute type you select.

Fields

•

Endpoint Attribute Type—Choose from the drop-down list the endpoint attribute you want to set.

Options include Antispyware, Antivirus, Application, File, NAC, Operating System, Personal

Firewall, Process, Registry, VLAN, and Priority.

Endpoint attributes include these components, but not all attributes include all components. The following descriptions show (in parentheses) the attributes to which each component applies.

•

•

•

•

•

Exists/Does not exist buttons (Antispyware, Antivirus, Application, File, NAC, Operating System,

Personal Firewall, Process, Registry, VLAN, Priority)— Click the appropriate button to indicate whether the selected endpoint attribute and its accompanying qualifiers (fields below the

Exists/Does not exist buttons) should be present or not.

Vendor ID (Antispyware, Antivirus, Personal Firewall)—Identify the application vendor.

Vendor Description (Antispyware, Antivirus, Personal Firewall)—Provide text that describes the application vendor.

Version (Antispyware, Antivirus, Personal Firewall)—Identify the version of the application, and specify whether you want the endpoint attribute to be equal to/not equal to that version.

Last Update (Antispyware, Antivirus, File)—Specify the number of days since the last update. You might want to indicate that an update should occur in less than (<) or more than (>) the number of days you enter here.

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•

•

•

•

•

•

•

•

•

•

•

•

Client Type (Application)—Indicate the type of remote access connection, AnyConnect, Clientless,

Cut-through Proxy, IPsec, or L2TP.

Checksum (File)—Select the file and click the Compute Checksum button to arrive at this value.

Compute CRC32 Checksum (File)—Use this calculator to determine the checksum value of a file.

Posture Status (NAC)—Contains the posture token string received from ACS.

OS Version (Operating System)—Windows (various), MAC, Linux, Pocket PC.

Service Pack (Operating System)—Identify the service pack for the operating system.

Endpoint ID (File, Process, Registry)—A string that identifies an endpoint for files, processes or registry entries. DAP uses this ID to match Cisco Secure Desktop host scan attributes for DAP selection. You must configure Host Scan before you configure this attribute. When you configure

Host Scan, the configuration displays in this pane, so you can select it, reducing the possibility of errors in typing or syntax.

Path (Process, Policy)—Configure Host Scan before you configure this attribute. When you configure Host Scan, the configuration displays in this pane, so you can select it, reducing the possibility of errors in typing or syntax.

Value (Registry)—dword or string

Caseless (Registry)—Select to disregard case in registry entries.

VLAN ID (VLAN)—A valid 802.1q number ranging from 1 to 4094

VLAN Type (VLAN)—Possible values include the following:

ACCESS

STATIC

TIMEOUT

AUTH

GUEST

QUARANTINE

ERROR

Posture assessment passed

No posture assessment applied

Posture assessment failed due to no response

Posture assessment still active

Posture assessment passed, switch to guest VLAN

Posture assessment failed, switch to quarantine VLAN

Posture assessment failed due to fatal error

•

Policy (Location)—Enter the Cisco Secure Desktop Microsoft Windows location profile, case sensitive.

Modes


Firewall Mode

Routed

•


•


Multiple

•

Context

—

System

—

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Guide

This section provides information about constructing logical expressions for AAA or Endpoint attributes. Be aware that doing so requires sophisticated knowledge of Lua ( www.lua.org

).

In the Advanced field you enter free-form Lua text that represents AAA and/or endpoint selection logical operations. ASDM does not validate text that you enter here; it just copies this text to the DAP policy file, and the adaptive security appliance processes it, discarding any expressions it cannot parse.

This option is useful for adding selection criteria other than what is possible in the AAA and endpoint attribute areas above. For example, while you can configure the adaptive security appliance to use AAA attributes that satisfy any, all, or none of the specified criteria, endpoint attributes are cumulative, and must all be satisfied. To let the security appliance employ one endpoint attribute or another, you need to create appropriate logical expressions in Lua and enter them here.

•

For a list of AAA Selection attributes, including proper name syntax for creating logical expressions, see Table 65-1 .

•

For a list of endpoint selection attributes, including proper name syntax for creating logical expressions, see

Table 65-3 .

The following sections provide detailed explanations of creating Lua EVAL expressions, as well as examples.

•

•

Syntax for Creating Lua EVAL Expressions

–

Constructing DAP EVAL Expressions

The DAP CheckAndMsg Function

–

Checking for a Single Antivirus Program

–

–

Checking for Antivirus Definitions Within the Last 10 Days

Checking for a Hotfix on the User PC

•

•

•

–

–

Checking for Antivirus Programs

Checking for Antivirus Programs and Definitions Older than 1 1/2 Days

Additional Lua Functions

–

OU-Based Match Example

–

–

Group Membership Example

Antivirus Example

–

–

Antispyware Example

Firewall Example

–

Antivirus, Antispyware, or any Firewall Example

CheckAndMsg with Custom Function Example

Further Information on Lua

Syntax for Creating Lua EVAL Expressions

This section provides information about the syntax for creating Lua EVAL expressions.

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Note

If you must use Advanced mode, we recommend that you use EVAL expressions whenever possible for reasons of clarity, which makes verifying the program straightforward.

EVAL(<

attribute

> , <comparison>, {<

value

> | <

attribute

>}, [<type>])

<attribute>

<comparison>

<value>

<type>

AAA attribute or an attribute returned from Cisco Secure Desktop, see

Table 65-1 and

Table 65-3 for attribute definitions

One of the following strings (quotation marks required)

“EQ”

“NE”

“LT”

“GT” equal not equal less than greater than

“LE”

“GE” less than or equal greater than or equal

A string in quotation marks that contains the value to compare the attribute against

One of the following strings (quotation marks required)

“string”

“caseless”

“integer”

“hex”

“version” case-sensitive string comparison case-insensitive string comparison number comparison, converts string values to numbers number comparison using hexadecimal values, converts hex string to hex numbers compares versions of the form X.Y.Z. where X, Y, and Z are numbers

Example

:

EVAL(endpoint.os.version, “EQ”, “Windows XP”, “string”)

Constructing DAP EVAL Expressions

Study these examples for help in creating logical expressions in Lua.

•

This endpoint expression tests for a match on CLIENTLESS OR CVC client types:

(EVAL(endpoint.application.clienttype,”EQ”,"CLIENTLESS") or

EVAL(endpoint.application.clienttype, “EQ”,"CVC"))

•

This endpoint expression tests for Norton Antivirus versions 10.x but excludes 10.5.x:

(EVAL(endpoint.av[“NortonAV”].version, “GE”, "10",”version”) and

(EVAL(endpoint.av[“NortonAV”].version,”LT”, "10.5", “version”) or

EVAL(endpoint.av[“NortonAV”].version, “GE”, "10.6", “version”)))

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The DAP CheckAndMsg Function

CheckAndMsg is a Lua function that you can configure DAP to call. It generates a user message based on a condition.

You use ASDM to configure CheckAndMsg through the Advanced field in DAP. The adaptive security appliance displays the message to the user only when the DAP record containing the LUA

CheckAndMsg function is selected and results in a clientless SSL VPN or AnyConnect termination.

The syntax of the CheckAndMsg function follows:

CheckAndMsg(value, “<message string if value is true>”, “<message string if value if false>”)

Be aware of the following when creating CheckAndMsg functions:

•

•

CheckAndMsg returns the value passed in as its first argument.

Use the EVAL function as the first argument if you do not want to use string comparison. For example:

(CheckAndMsg((EVAL(...)) , "true msg", "false msg"))

CheckandMsg returns the result of the EVAL function and the security appliances uses it to determine whether to select the DAP record. If the record is selected and results in termination, the security appliance displays the appropriate message.

Checking for a Single Antivirus Program

This example checks if a single antivirus program, in this case McAfee, is installed on the user PC, and displays a message if it is not.

(CheckAndMsg(EVAL(endpoint.av[“McAfeeAV”].exists,"NE","true"),"McAfee AV was not found on your computer", nil))

Checking for Antivirus Definitions Within the Last 10 Days

This example checks antivirus definitions within the last 10 days (864000 sec), in particular the last update of the McAfee AV dat file, and displays a message to a user lacking the appropriate update that they need an antivirus update:

((CheckAndMsg(EVAL(endpoint.av

[“McAfeeAV”]

.lastupdate,"GT","864000","integer"),"AV

Update needed! Please wait for the McAfee AV till it loads the latest dat file.",nil) ))

Checking for a Hotfix on the User PC

This example checks for a specific hotfix. If a user does not have the hotfix on their PC, a message that it is not installed displays.

(not CheckAndMsg(EVAL(endpoint.os.windows.hotfix["KB923414"],"EQ","true"),nil,"The required hotfix is not installed on your PC.")) or you could define it this way (which makes more sense):

(CheckAndMsg(EVAL(endpoint.os.windows.hotfix["KB923414"],"NE","true"),"The required hotfix is not installed on your PC.",nil))

You can build the expression in this example because the debug dap trace returns:

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endpoint.os.windows.hotfix["KB923414"] = "true";

Checking for Antivirus Programs

You can configure messages so that the end user is aware of and able to fix problems with missing or not running AVs. As a result, if access is denied, the adaptive security appliance collects all messages for the DAP that caused the "terminate" condition and displays them in the browser on the logon page. If access is allowed, the adaptive security appliance displays all messages generated in the process of DAP evaluation on the portal page.

The following example shows how to use this feature to check on the Norton Antivirus program.

Step 1

Step 2

Step 3

Step 4

Step 5

Copy and paste the following Lua expression into the Advanced field of the Add/Edit Dynamic Access

Policy pane (click the double arrow on the far right to expand the field).

(CheckAndMsg(EVAL(endpoint.av[“NortonAV”].exists, "EQ", "false"),"Your Norton AV was found but the active component of it was not enabled", nil) or

CheckAndMsg(EVAL(endpoint.av[“NortonAV”].exists, "NE", "true"),"Norton AV was not found on your computer", nil) )

In that same Advanced field, click the

OR

button.

In the Access Attributes section below, in the leftmost tab, Action

,

click

Terminate

.

Connect from a PC that does not have or has disabled Norton Antivirus.

The expected result is that the connection is not allowed

and

the message appears as a blinking ! point.

Click the blinking ! to see the message.

Checking for Antivirus Programs

and

Definitions Older than 1 1/2 Days

This example checks for the presence of the Norton and McAfee antivirus programs, and whether the virus definitions are older than 1 1/2 days (10,000 seconds). If the definitions are older than 1 1/2 days, the adaptive security appliance terminates the session with a message and links for remediation. To accomplish this task, perform the following steps.

Step 1

Copy and paste the following Lua expression into the Advanced field of the Add/Edit Dynamic Access

Policy pane (click the double arrow on the far right to expand the field):

((EVAL(endpoint.av[“NortonAV”].exists,”EQ”,”true”,”string”) and

CheckAndMsg(EVAL(endpoint.av[“NortonAV”].lastupdate,”GT”,”10000”,integer”),To remediate <a href=’http://www.symantec.com’>Click this link </a>”,nil)) or

(EVAL(endpoint.av[“McAfeeAV”].exists,”EQ”,”true”,”string”) and

CheckAndMsg(EVAL(endpoint.av[“McAfeeAV”].lastupdate,”GT”,”10000”,integer”),To remediate <a href=’http://www.mcafee.com’>Click this link</a>”,nil))

Step 2

Step 3

Step 4

In that same Advanced field, click

AND

.

In the Access Attributes section below, in leftmost tab, Action

,

click

Terminate

.

Connect from a PC that has Norton and McAfee antivirus programs with versions that are older than

1 1/2 days.

The expected result is that the connection is not allowed

and

the message appears as a blinking ! point.

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65-25



Step 5

Click the blinking ! to see the message and links for remediation.

Additional Lua Functions

When working with dynamic access policies for clientless SSL VPN, you might need additional flexibility of match criteria. For example, you might want to apply a different DAP based on the following:

•

Organizational Unit (OU) or other level of the hierarchy for the user object

•

Group Name that follows a naming convention but has many possible matches—you might require the ability to use a wildcard on group names.

You can accomplish this flexibility by creating a Lua logical expression in the Advanced section of the

DAP pane in ASDM.

OU-Based Match Example

DAP can use many attributes returned from an LDAP server in a logical expression. See the DAP trace section for example output of this, or run a debug dap trace.

The LDAP server returns the user Distinguished Name (DN). This implicitly identifies where in the directory the user object is located. For example, if the user DN is CN=Example

User,OU=Admins,dc=cisco,dc=com this user is located in OU=Admins,dc=cisco,dc=com. If all administrators are in this OU (or any container below this level) you can use a logical expression to match on this criteria as follows: assert(function()

if ( (type(aaa.ldap.distinguishedName) == "string") and

(string.find(aaa.ldap.distinguishedName, "OU=Admins,dc=cisco,dc=com$") ~= nil) ) then

return true

end

return false end)()

In this example, the string.find function allows for a regular expression. Use the $ at the end of the string to anchor this string to the end of the distinguishedName field.

Group Membership Example

You can create a basic logical expression for pattern matching of AD group membership. Because users can be members of multiple groups, DAP parses the response from the LDAP server into separate entries in a table. You need an advanced function to accomplish the following:

•

Compare the memberOf field as a string (in the event the user belongs to only one group).

•

Iterate through each returned memberOf field if the returned data is of type "table".

The function we have written and tested for this purpose is shown below. In this example, if a user is a member of any group ending with "-stu" they match this DAP.

assert(function()

local pattern = "-stu$"

local attribute = aaa.ldap.memberOf

if ((type(attribute) == "string") and

(string.find(attribute, pattern) ~= nil)) then

return true

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elseif (type(attribute) == "table") then

local k, v

for k, v in pairs(attribute) do

if (string.find(v, pattern) ~= nil) then

return true

end

end

end

return false end)()

Antivirus Example

Antispyware Example

The following example uses a custom function to check if CSD detects any antispyware.

assert(function()

for k,v in pairs(endpoint.as) do

if (EVAL(v.exists, "EQ", "true", "string")) then

return true

end

end

return false end)()

Firewall Example

The following example uses a custom function to check if CSD detects any antivirus software.

assert(function()

for k,v in pairs(endpoint.av) do


return true

end

end

return false end)()

The following example uses a custom function to check if CSD detects a firewall.

assert(function()

for k,v in pairs(endpoint.fw) do


return true

end

end

return false end)()

Antivirus, Antispyware,

or

any Firewall Example

The following example uses a custom function to check if CSD detects any antivirus, antispyware, or any firewall.

assert(function()

function check(antix)

if (type(antix) == "table") then

for k,v in pairs(antix) do


return true

end

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end

end

return false

end

return (check(endpoint.av) or check(endpoint.fw) or check(endpoint.as))

end)()

CheckAndMsg with Custom Function Example

You can use the following function to deny access in the absence of an antivirus program. Use it with a

DAP that has Action set to terminate.

assert( function() for k,v in pairs(endpoint.av) do if (EVAL(v.exists, "EQ”, "true", "string")) then return false end end return CheckAndMsg(true, "Please install antivirus software before connecting.", nil) end)()

If a user lacking an antivirus program attempts to log in, DAP displays the following message:

Please install antivirus software before connecting.

Further Information on Lua

You can find detailed LUA programming information at http://www.lua.org/manual/5.1/manual.html

.

Operator for Endpoint Category

You can configure multiple instances of each type of endpoint. In this pane, set each type of endpoint to require only one instance of a type (Match Any = OR) or to have all instances of a type (Match All =

AND).

•

If you configure only one instance of an endpoint category, you do not need to set a value.

•

For some endpoint attributes, it makes no sense to configure multiple instances. For example, no users have more than one running OS.

You are configuring the Match Any/Match All operation within each endpoint type.

•

The security appliance evaluates each type of endpoint attribute, and then performs a logical AND operation on all of the configured endpoints. That is, each user must satisfy the conditions of ALL of the endpoints you configure, as well as the AAA attributes.

DAP Examples

The following sections provide examples of useful dynamic access policies.

•

•

•

Using DAP to Define Network Resources

Using DAP to Apply a WebVPN ACL

Enforcing CSD Checks and Applying Policies via DAP

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Using DAP to Define Network Resources

This example shows how to configure dynamic access policies as a method of defining network resources for a user or group. The DAP policy named Trusted_VPN_Access permits clientless and

AnyConnect VPN access. The policy named Untrusted_VPN_Access permits only clientless VPN access.

Table 65-4

summarizes the configuration of each of these policies.

The ASDM path is Configuration > Remote Access VPN > Clientless SSL VPN Access > Dynamic

Access Policies > Add/Edit Dynamic Access Policy > Endpoint

Table 65-4 A Simple DAP Configuration for Network Resources

Attribute

Endpoint Attribute Type Policy

Endpoint Attribute Process

Advanced Endpoint Assessment

CSD Location

LDAP memberOf

ACL

Access

Trusted_VPN_Access

Trusted

ieexplore.exe

AntiVirus= McAfee Attribute

Trusted

Engineering, Managers

AnyConnect

and

Web Portal

Untrusted_VPN_Access

Untrusted

—

Untrusted

Vendors

Web-Type ACL

Web Portal

Using DAP to Apply a WebVPN ACL

DAP can directly enforce a subset of access policy attributes including Network ACLs (for IPsec and

AnyConnect), clientless SSL VPN Web-Type ACLs, URL lists, and Functions. It cannot directly enforce, for example, a banner or the split tunnel list, which the group policy enforces. The Access

Policy Attributes tabs in the Add/Edit Dynamic Access Policy pane provide a complete menu of the attributes DAP directly enforces.

Active Directory/LDAP stores user group policy membership as the “memberOf” attribute in the user entry. You can define a DAP such that for a user in AD group (memberOf) = Engineering the adaptive security appliance applies a configured Web-Type ACL. To accomplish this task, perform the following steps:

Step 2

Step 3

Step 4

Step 5

Step 6

Step 1

Navigate to the Add AAA attributes pane (Configuration > Remote Access VPN > Clientless SSL VPN

Access > Dynamic Access Policies > Add/Edit Dynamic Access Policy > AAA Attributes section > Add

AAA Attribute).

For the AAA Attribute type, use the drop-down menu to choose LDAP.

In the Attribute ID field, enter memberOf, exactly as you see it here. Case is important.

In the Value field, use the drop-down menu to choose =, and in the adjacent field enter Engineering.

In the Access Policy Attributes area of the pane, click the Web-Type ACL Filters tab.

Use the Web-Type ACL drop-down menu to select the ACL you want to apply to users in the AD group

(memberOf) = Engineering.

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Enforcing CSD Checks and Applying Policies via DAP

This example creates a DAP that checks that a user belongs to two specific AD/LDAP groups

(Engineering and Employees) and a specific ASA tunnel group. It then applies an ACL to the user.

The ACLs that DAP applies control access to the resources. They override any ACLS defined the group policy on the adaptive security appliance. In addition, the adaptive security appliance applied the regular

AAA group policy inheritance rules and attributes for those that DAP does not define or control, examples being split tunneling lists, banner, and DNS. To accomplish this task, perform the following steps.

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 1

Step 9

Navigate to the Add AAA attributes pane (Configuration > Remote Access VPN > Clientless SSL VPN

Access > Dynamic Access Policies > Add/Edit Dynamic Access Policy > AAA Attributes section > Add

AAA Attribute).

For the AAA Attribute type, use the drop-down menu to choose LDAP.


In the Value field, use the drop-down menu to choose =, and in the adjacent field enter Engineering.


In the Value field, use the drop-down menu to select =, and in the adjacent field enter Employees.

For the AAA attribute type, use the drop-down menu to choose Cisco.

Check the Tunnel group box, use the drop-down menu to choose =, and in the adjacent drop-down list select the appropriate tunnel group (connection policy).

In the Network ACL Filters tab of the Access Policy Attributes area, choose the ACLs to apply to users who meet the DAP criteria defined in the previous steps.

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C H A P T E R

66

Clientless SSL VPN End User Set-up

This section is for the system administrator who sets up Clientless (browser-based) SSL VPN for end users. It summarizes configuration requirements and tasks for the user remote system. It also specifies information to communicate to users to get them started using Clientless SSL VPN. This section includes the following topics:

•

Requiring Usernames and Passwords

•

•

•

Communicating Security Tips

Configuring Remote Systems to Use Clientless SSL VPN Features

Capturing Clientless SSL VPN Data

Note

We assume you have already configured the adaptive security appliance for Clientless SSL VPN.

Requiring Usernames and Passwords

Depending on your network, during a remote session users might have to log in to any or all of the following: the computer itself, an Internet service provider, Clientless SSL VPN, mail or file servers, or corporate applications. Users might have to authenticate in many different contexts, requiring different information, such as a unique username, password, or PIN.

Table 66-1

lists the type of usernames and passwords that Clientless SSL VPN users might need to know.

Table 66-1 Usernames and Passwords to Give to Clientless SSL VPN Users

Login Username/

Password Type

Computer

Internet Service Provider

Clientless SSL VPN

Mail Server

Purpose

Access the computer

Access the Internet

Access remote network

File Server Access remote file server Using the Clientless SSL VPN file browsing feature to access a remote file server

Corporate Application Login Access firewall-protected internal server Using the Clientless SSL VPN web browsing feature to access an internal protected website

Access remote mail server via Clientless

SSL VPN

Entered When

Starting the computer

Connecting to an Internet service provider

Starting a Clientless SSL VPN session

Sending or receiving e-mail messages

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Chapter 66 Clientless SSL VPN End User Set-up

Communicating Security Tips

Communicating Security Tips

Advise users always to log out from the session. (To log out of Clientless SSL VPN, click the logout icon on the Clientless SSL VPN toolbar or close the browser.)

Advise users that using Clientless SSL VPN does not ensure that communication with every site is secure. Clientless SSL VPN ensures the security of data transmission between the remote PC or workstation and the adaptive security appliance on the corporate network. If a user then accesses a non-HTTPS web resource (located on the Internet or on the internal network), the communication from the corporate adaptive security appliance to the destination web server is not secure.

Configuring Remote Systems to Use Clientless SSL VPN

Features

Table 66-2 includes the following information about setting up remote systems to use Clientless SSL

VPN:

•

Starting Clientless SSL VPN

•

•

•

Using the Clientless SSL VPN Floating Toolbar

Web Browsing

Network Browsing and File Management

Using Applications (Port Forwarding)

•

•

•

•

Using E-mail via e-mail proxy

Table 66-2 also provides information about the following:

•

•

•

•

Using E-mail via Port Forwarding

Using E-mail via Web Access

Clientless SSL VPN requirements, by feature

Clientless SSL VPN supported applications

Client application installation and configuration requirements

Information you might need to provide end users

•

Tips and use suggestions for end users

It is possible you have configured user accounts differently and that different features are available to

each Clientless SSL VPN user. Table 66-2 organizes information by feature, so you can skip over the

information for unavailable features.

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Configuring Remote Systems to Use Clientless SSL VPN Features

Table 66-2 Clientless SSL VPN Remote System Configuration and End User Requirements

Task

Starting Clientless SSL

VPN

Remote System or End User Requirements

Connection to the Internet

Clientless SSL VPN-supported browser

Specifications or Use Suggestions

Any Internet connection is supported, including:

•

Home DSL, cable, or dial-ups

•

•

Public kiosks

Hotel hook-ups

•

•

Airport wireless nodes

Internet cafes

We recommend the following browsers for

Clientless SSL VPN. Other browsers might not fully support Clientless SSL VPN features.

On Microsoft Windows:

•

Internet Explorer version 6.0

•

Firefox 1.x

On Linux:

Cookies enabled on browser

URL for Clientless SSL VPN

•

Firefox 1.x

On Macintosh OS X:

•

•

Safari version 1.0

Firefox 1.x

Cookies must be enabled on the browser in order to access applications via port forwarding.

An https address in the following form: https://

address

where

address

is the IP address or DNS hostname of an interface of the adaptive security appliance

(or load balancing cluster) on which Clientless

SSL VPN is enabled. For example: https://10.89.192.163 or https://cisco.example.com.

Clientless SSL VPN username and password

[Optional] Local printer Clientless SSL VPN does not support printing from a web browser to a network printer. Printing to a local printer is supported.

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Table 66-2

Task

Clientless SSL VPN Remote System Configuration and End User Requirements (continued)

Using the Floating

Toolbar in a Clientless

SSL VPN Connection

Remote System or End User Requirements Specifications or Use Suggestions

A floating toolbar is available to simplify the use of Clientless SSL VPN. The toolbar lets you enter

URLs, browse file locations, and choose preconfigured web connections without interfering with the main browser window.

If you configure your browser to block popups, the floating toolbar cannot display.

The floating toolbar represents the current

Clientless SSL VPN session. If you click the

Close

button, the adaptive security appliance prompts you to confirm that you want to close the Clientless

SSL VPN session.

Web Browsing

Usernames and passwords for protected websites

Tip

TIP: To paste text into a text field, use

Ctrl-V. (Right-clicking is disabled on the

Clientless SSL VPN toolbar.)

Using Clientless SSL VPN does not ensure that communication with every site is secure. See

“ Communicating Security Tips .”

The look and feel of web browsing with Clientless

SSL VPN might be different from what users are accustomed to. For example:

•

•

The Clientless SSL VPN title bar appears above each web page.

You access websites by:

–

–

Entering the URL in the Enter Web

Address field on the Clientless SSL VPN

Home page.

Clicking on a preconfigured website link on the Clientless SSL VPN Home page.

–

Clicking a link on a webpage accessed via one of the previous two methods.

Also, depending on how you configured a particular account, it might be that:

•

•

Some websites are blocked.

Only the web sites that appear as links on the

Clientless SSL VPN Home page are available.

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Table 66-2 Clientless SSL VPN Remote System Configuration and End User Requirements (continued)

Task

Network Browsing and

File Management


File permissions configured for shared remote access

Server name and passwords for protected file servers

Domain, workgroup, and server names where folders and files reside

—


Only shared folders and files are accessible via

Clientless SSL VPN.

—

Users might not be familiar with how to locate their files through your organization network.

Do not interrupt the

Copy File to Server

command or navigate to a different screen while the copying is in progress. Interrupting the operation can cause an incomplete file to be saved on the server.

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Task

Using Applications

(called Port Forwarding or Application Access)


Note


On Macintosh OS X, only the Safari browser supports this feature.

Note

Because this feature requires installing Sun Microsystems Java™ Runtime Environment and configuring the local clients, and because doing so requires administrator permissions on the local system, it is unlikely that users will be able to use applications when they connect from public remote systems.

Caution

Users should always close the Application Access window when they finish using applications by clicking the

Close

icon. Failure to quit the window properly can cause

Application Access or the applications themselves to be disabled.

Client applications installed

Cookies enabled on browser

Administrator privileges

Sun Microsystems Java Runtime

Environment (JRE) version 1.4.x and 1.5.x installed.

Javascript must be enabled on the browser.

By default, it is enabled.

—

—

User must have administrator access on the PC if you use DNS names to specify servers because modifying the hosts file requires it.

If JRE is not installed, a pop-up window displays, directing users to a site where it is available.

On rare occasions, the port forwarding applet fails with JAVA exception errors. If this happens, do the following:

1.

2.

Clear the browser cache and close the browser.

Verify that no JAVA icons are in the computer task bar. Close all instances of JAVA.

3.

Establish a Clientless SSL VPN session and launch the port forwarding JAVA applet.

Client applications configured, if necessary.

Note

The Microsoft Outlook client does not require this configuration step.

To configure the client application, use the server’s locally mapped IP address and port number. To find this information:

All non-Windows client applications require configuration.

1.

Start Clientless SSL VPN on the remote system and click the Application Access link on the Clientless SSL VPN Home page. The

Application Access window appears.

To see if configuration is necessary for a

Windows application, check the value of the

Remote Server.

•

If the Remote Server contains the server hostname, you do not need to configure the client application.

2.

3.

In the Name column, find the name of the server you want to use, then identify its corresponding client IP address and port number (in the Local column).

•

If the Remote Server field contains an IP address, you must configure the client application.

Use this IP address and port number to configure the client application. Configuration steps vary for each client application.

Note

Clicking a URL (such as one in an -e-mail message) in an application running over

Clientless SSL VPN does not open the site over Clientless SSL VPN. To open a site over

Clientless SSL VPN, cut and paste the URL into the Enter (URL) Address field.

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Capturing Clientless SSL VPN Data


Task

Using E-mail via Application Acces

s

Using E-mail via

Web Access

Using E-mail via

E-mail Proxy


Fulfill requirements for Application Access

(See Using Applications)


To use mail, start Application Access from the

Clientless SSL VPN Home page. The mail client is then available for use.

Note

If you are using an IMAP client and you lose your mail server connection or are unable to make a new connection, close the IMAP application and restart Clientless SSL VPN.

Other mail clients We have tested Microsoft Outlook Express versions 5.5 and 6.0.

Web-based e-mail product installed

Clientless SSL VPN should support other SMTPS,

POP3S, or IMAP4S e-mail programs via port forwarding, such as Lotus Notes, and Eudora, but we have not verified them.

Supported products include:

SSL-enabled mail application installed

Do not set the adaptive security appliance

SSL version to TLSv1 Only. Outlook and

Outlook Express do not support TLS.

•

•

Outlook Web Access

For best results, use OWA on Internet

Explorer 6.x or higher, or Firefox 1.x.

Lotus iNotes

Other web-based e-mail products should also work, but we have not verified them.

Supported mail applications:

•

Microsoft Outlook

•

Microsoft Outlook Express versions 5.5 and

6.0

Eudora 4.2 for Windows 2000

•

Other SSL-enabled mail clients should also work, but we have not verified them.

Mail application configured


The CLI capture command lets you log information about websites that do not display properly over a

Clientless SSL VPN connection. This data can help your Cisco customer support engineer troubleshoot problems. The following sections describe how to use the capture command:

•

•

Creating a Capture File

Using a Browser to Display Capture Data

Note

Enabling Clientless SSL VPN capture affects the performance of the security appliance. Be sure to disable the capture after you generate the capture files needed for troubleshooting.

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Creating a Capture File

Perform the following steps to capture data about a Clientless SSL VPN session to a file.

Step 1

Step 2

Step 3

Step 4

To start the Clientless SSL VPN capture utility, use the

capture

command from privileged EXEC mode.

capture

capture_name

type webvpn user

webvpn_username

where:

•

capture_name

is a name you assign to the capture, which is also prepended to the name of the capture files.

•

webvpn_user

is the username to match for capture.

The capture utility starts.

A user logs in to begin a Clientless SSL VPN session. The capture utility is capturing packets.

Stop the capture by using the

no

version of the command.

no capture

capture_name

The capture utility creates a

capture_name

.zip

file, which is encrypted with the password

koleso

.

Send the .zip file to Cisco Systems, or attach it to a Cisco TAC service request.

To look at the contents of the .zip file, unzip it using the password

koleso

.

The following example creates a capture named

hr

, which captures Clientless SSL VPN traffic for user2 to a file: hostname#

capture hr type webvpn user user2

WebVPN capture started.

capture name hr

user name user2 hostname#

no capture hr

Using a Browser to Display Capture Data

Perform the following steps to capture data about a Clientless SSL VPN session and view it in a browser.

Step 1

Step 2

Step 3

To start the Clientless SSL VPN capture utility, use the

capture

command from privileged EXEC mode.

capture

capture_name

type webvpn user

webvpn_username

where:

•

•

capture_name

is a name you assign to the capture, which is also prepended to the name of the capture files.

webvpn_username

is the username to match for capture.

The capture utility starts.

A user logs in to begin a Clientless SSL VPN session. The capture utility is capturing packets.

Stop the capture by using the

no


Open a browser and in the address box enter

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Step 4 https://

IP_address or hostname of the adaptive security appliance/

webvpn_capture.html

The captured content displays in a sniffer format.

When you finish examining the capture content, stop the capture by using the

no


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C H A P T E R

67


Clientless SSL VPN lets users establish a secure, remote-access VPN tunnel to the adaptive security appliance using a web browser. There is no need for either a software or hardware client. Clientless SSL

VPN provides easy access to a broad range of web resources and both web-enabled and legacy applications from almost any computer that can reach HTTPS Internet sites. Clientless SSL VPN uses

Secure Socket Layer Protocol and its successor, Transport Layer Security (SSL/TLS1) to provide a secure connection between remote users and specific, supported internal resources that you configure at a central site. The adaptive security appliance recognizes connections that need to be proxied, and the

HTTP server interacts with the authentication subsystem to authenticate users.

The network administrator provides access to network resources on a user or group basis. Users have no direct access to these resources.

Clientless SSL VPN works on the platform in single, routed mode.

For information on configuring clientless SSL VPN for end users, see Customizing the Clientless SSL

VPN User Experience .

Security Precautions

Clientless SSL VPN connections on the adaptive security appliance differ from remote access IPSec connections, particularly with respect to how they interact with SSL-enabled servers, and precautions to follow to reduce security risks.

In a clientless SSL VPN connection, the adaptive security appliance acts as a proxy between the end user web browser and target web servers. When a user connects to an SSL-enabled web server, the adaptive security appliance establishes a secure connection and validates the server SSL certificate. The browser never receives the presented certificate, so it cannot examine and validate the certificate.

Note

Browser-based VPN access does not save form-based authentication values to permanent local storage.

The current implementation of clientless SSL VPN on the adaptive security appliance does not permit communication with sites that present expired certificates. Nor does the adaptive security appliance perform trusted CA certificate validation to those SSL-enabled sites. Therefore, users do not benefit from certificate validation of pages delivered from an SSL-enabled web server before they use a web-enabled service.


67-1 OL-20339-01

Chapter 67 Clientless SSL VPN

Security Precautions

By default, the adaptive security appliance permits all portal traffic to all web resources (e.g., HTTPS,

CIFS, RDP, and plug-ins). The adaptive security appliance clientless service rewrites each URL to one that is meaningful only to the adaptive security appliance; the user cannot use the rewritten URL displayed on the page accessed to confirm that they are on the site they requested (see example Figures

67-1

and

67-2

).

Figure 67-1 Example URL Typed by User

Figure 67-2 Same URL Rewritten by Security Appliance and displayed on the Browser Window

Caution

To avoid placing users at risk, please assign a web ACL to the policies configured for clientless access

– group-policies, dynamic access policies, or both – to control traffic flows from the portal. For example, without such an ACL, users could receive an authentication request from an outside fraudulent banking or commerce site. Also, we recommend disabling URL Entry on these policies to prevent user confusion over what is accessible. The procedure that follows steps you through the recommendations in this statement.

We recommend that you do the following to minimize risks posed by clientless SSL VPN access:

Step 1

Step 2

Step 3

Step 4

Configure a group policy for all users who need clientless SSL VPN access, and enable clientless SSL

VPN only for that group policy.

With the group policy open, choose

General

>

More Options

>

Web ACL

and click

Manage

. Create a web ACL to do one of the following: permit access only to specific targets within the private network, permit access only to the private network, deny Internet access, or permit access only to reputable sites.

Assign the web ACL to any policies (group policies, dynamic access policies, or both) that you have configured for clientless access. To assign a web ACL to a DAP, edit the DAP record, and select the web

ACL on the

Network ACL Filters

tab.

Disable URL entry on the

portal page

, the page that opens upon the establishment of a browser-based connection. To do so, click

Disable

next to URL Entry on both the group policy Portal frame and the

DAP

Functions

tab.

Instruct users to enter external URLs in the native browser address field above the portal page or open a separate browser window to visit external sites.

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Understanding Clientless SSL VPN System Requirements

Understanding Clientless SSL VPN System Requirements

Release 8.3(1) supports browser-based (clientless) VPN access from the following platforms:

•

Windows 7 x86 (32-bit) and x64 (64-bit) via Internet Explorer 8.x and Firefox 3.x.

•

•

Windows Vista x64 via Internet Explorer 7.x–8.x, or Firefox 3.x.

Windows Vista x86 SP2, or Vista SP1 with KB952876 or later, via Internet Explorer 7.x, or Firefox

3.x.

•

•

•

Windows XP x64 via Internet Explorer 7.x–8.x and Firefox 3.x.

Windows XP x86 SP2 or later via Internet Explorer 6.x–8.x, or Firefox 3.x.

Mac OS 10.6.x or 10.5 32- and 64-bit via Safari 3.x–4.x and Firefox 3.x with Sun JRE 1.5 or later.

Certificate authentication, including the DoD Common Access Card and SmartCard, works with the

Safari keychain only.

Linux via Firefox 3.x

•

ActiveX pages require that you enable ActiveX Relay on the associated group policy. If you do so or assign a smart tunnel list to the policy, and the browser proxy exception list on the endpoint specifies a proxy, the user must add a “shutdown.webvpn.relay.” entry to that list.

The ASA supports clientless access to Lotus iNotes 8.5.

The ASA does not support clientless access to Windows Shares (CIFS) Web Folders from Windows 7,

Vista, Internet Explorer 8, Mac OS, and Linux. Windows XP SP2 requires a Microsoft hotfix to support

Web Folders.

The ASA does not support DSA certificates; it does support RSA certificates.

See the following sections for the platforms supported by these clientless applications:

•

Port Forwarding Requirements and Restrictions, page 67-23

•

•

Smart Tunnel Requirements and Limitations, page 67-35

Plug-in Requirements and Restrictions, page 67-78


The Clientless SSL VPN Access pane lets you accomplish the following tasks:

•

•

•

•

Enable or disable adaptive security appliance interfaces for clientless SSL VPN sessions.

Choose a port for clientless SSL VPN connections.

Set a global timeout value for clientless SSL VPN sessions.

Set a maximum number of simultaneous clientless SSL VPN sessions.

•

Configure the amount of adaptive security appliance memory that clientless SSL VPN can use.

To configure clientless SSL VPN services for individual users, the best practice is to choose the

Configuration > VPN > General > Group Policy >Add/Edit >WebVPN

pane. Then choose the

Configuration > Properties >Device Administration >User Accounts > VPN Policy

pane to assign the group policy to a user.

Fields

•

Configure access parameters for WebVPN—Lets you enable or disable clientless SSL VPN connections on configured adaptive security appliance interfaces.


OL-20339-01 67-3



•

•

•

•

•

•

–

Interface—Displays names of all configured interfaces.

–

WebVPN Enabled—Displays current status for clientless SSL VPN on the interface.

A green check next to Yes indicates that clientless SSL VPN is enabled.

–

A red circle next to No indicates that clientless SSL VPN is disabled.

Enable/Disable—Click to enable or disable clientless SSL VPN on the highlighted interface.

Port Number—Enter the port number that you want to use for clientless SSL VPN sessions. The default port is 443, for HTTPS traffic; the range is 1 through 65535. If you change the port number,

All current clientless SSL VPN connections terminate, and current users must reconnect. You also lose connectivity to ASDM, and a prompt displays, inviting you to reconnect.

Default Idle Timeout—Enter the amount of time, in seconds, that a clientless SSL VPN session can be idle before the adaptive security appliance terminates it. This value applies only if the Idle

Timeout value in the group policy for the user is set to zero (0), which means there is no timeout value; otherwise the group policy Idle Timeout value takes precedence over the timeout you configure here. The minimum value you can enter is 1 minute. The default is 30 minutes (1800 seconds). Maximum is 24 hours (86400 seconds).

We recommend that you set this attribute to a short time period. This is because a browser set to disable cookies (or one that prompts for cookies and then denies them) can result in a user not connecting but nevertheless appearing in the sessions database. If the Simultaneous Logins attribute for the group policy is set to one, the user cannot log back in because the database indicates that the maximum number of connections already exists. Setting a low idle timeout removes such phantom sessions quickly, and lets a user log in again.

Max. Sessions Limit—Enter the maximum number of clientless SSL VPN sessions you want to allow. Be aware that the different ASA models support clientless SSL VPN sessions as follows: ASA

5510 supports a maximum of 250; ASA 5520 maximum is 750; ASA 5540 maximum is 2500; ASA

5550 maximum is 5000.

WebVPN Memory Size—Enter the percent of total memory or the amount of memory in kilobytes that you want to allocate to clientless SSL VPN processes. The default is 50% of memory. Be aware that the different ASA models have different total amounts of memory as follows: ASA 5510—256

MB; ASA5520 —512 MB: ASA 5540—1GB, ASA 5550—4G. When you change the memory size, the new setting takes effect only after the system reboots.

WebVPN Memory (unlabeled)—Choose to allocate memory for clientless SSL VPN either as a percentage of total memory or as an amount of memory in kilobytes.

Enable Tunnel Group Drop-down List on WebVPN Login—Click to include a drop-down list of configured tunnel groups on the clientless SSL VPN end-user interface. Users select a tunnel group from this list when they log on. This field is checked by default. If you uncheck it, the user cannot select a tunnel group at logon.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

67-4


OL-20339-01


For More Information

Customizing the Clientless SSL VPN User Experience

ACLs

ACLs


•


•

•


At the end of each ACL, there is an implicit, unwritten rule that denies all traffic that is not permitted. If traffic is not explicitly permitted by an ACE (access control entry), the adaptive security appliance denies it. ACEs are referred to as rules in this topic.

This pane lets you add and edit ACLs to be used for clientless SSL VPN sessions, and the ACL entries each ACL contains. It also displays summary information about ACLs and ACEs, and lets you enable or disable them, and change their priority order.

Fields

•

Add ACL—Click to add an ACL or ACE. To insert a new ACE before or after an existing ACE, click

Insert

or

Insert After

.

•

•

Edit—Click to edit the highlighted ACE. When you delete an ACL, you also delete all of its ACEs.

No warning or undelete.

Delete—Click to delete the highlighted ACL or ACE. When you delete an ACL, you also delete all of its ACEs. No warning or undelete.

•

•

•

•

Move UP/Move Down—Highlight an ACL or ACE and click these buttons to change the order of

ACLs and ACEs. The adaptive security appliance checks ACLs to be applied to clientless SSL VPN sessions and their ACEs in the sequence determined by their position in the ACLs list until it finds a match.

+/-—Click to expand (

+

) or collapse (

-

) to view or hide the list of ACEs under each ACL.

No—Displays the priority of the ACEs under each ACL. The order in the list determines priority.

Enabled—Shows whether the ACE is enabled. When you create an ACE, by default it is enabled.

Clear the check box to disable an ACE.

•

•

•

•

•


Service—Displays the TCP service to which the ACE applies.

Action—Displays whether the ACE permits or denies clientless SSL VPN access.

Time—Displays the time range associated with the ACE.

Logging (Interval)—Displays the configured logging behavior, either disabled or with a specified level and time interval.

Modes


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67-5


ACLs

Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add ACL

This pane lets you create a new ACL.

For information about access rules and ACLs (including IPv6), see the

“Information About Access

Rules” section on page 30-1 .

For information about configuring access rules and ACLs (including IPv6), see

“Configuring Access

Rules” section on page 30-7 .

For information about EtherType access rules and ACLs, see the

“Configuring Access Rules” section on page 30-7

Fields

•

ACL Name—Enter a name for the ACL. Maximum 55 characters.

Add/Edit ACE

An Access Control Entry (or “access rule”) permits or denies access to specific URLs and services. You can configure multiple ACEs for an ACL. ACLs apply ACEs in priority order, acting on the first match.

For information about access rules (including IPv6), see the

“Information About Access Rules” section on page 30-1

.

For information about configuring access rules (including IPv6), see the

“Configuring Access Rules” section on page 30-7 .

Fields

•

Action—Permits or denies access to the specific networks, subnets, hosts, and web servers specified in the Filter group field.

•

Filter—Specifies a URL or an IP address to which you want to apply the filter (permit or deny user access).

–

–

URL—Applies the filter to the specified URL.

Protocols (unlabeled)—Specifies the protocol part of the URL address.

–

–

://x—Specifies the URL of the Web page to which to apply the filter.

TCP—Applies the filter to the specified IP address, subnet, and port.

–

–

IP Address—Specifies the IP address to which to apply the filter.

Netmask—Lists the standard subnet mask to apply to the address in the IP Address field.

–

Service—Identifies the service (such as https, kerberos, or any) to be matched. Displays a list of services from which you can select the service to display in the Service field.

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OL-20339-01


Configuring the Setup for Cisco Secure Desktop

•

•

–

Rule Flow Diagram—Graphically depicts the traffic flow using this filter. This area might be hidden.

Options—Specifies the logging rules. The default is Default Syslog.

–

Boolean operator (unlabeled)—Lists the boolean conditions (equal, not equal, greater than, less than, or range) to use in matching the service specified in the service field.

–

Logging—Choose enable if you want to enable a specific logging level.

Syslog Level—Grayed out until you select Enable for the Logging attribute. Lets you select the type of syslog messages you want the adaptive security appliance to display.

–

–

–

Log Interval—Lets you select the number of seconds between log messages.

Time Range—Lets you select the name of a predefined time-range parameter set.

...—Click to browse the configured time ranges or to add a new one.

Examples

Here are examples of ACLs for clientless SSL VPN:

Action Filter

Deny url http://*.yahoo.com/

Effect

Denies access to all of Yahoo!

Deny url cifs://fileserver/share/directory

Deny url https://www.company.com/ directory/file.html Denies access to the specified file.

Permit url https://www.company.com/directory Permits access to the specified location

Deny url http://*:8080/

Denies access to all files in the specified location.

Deny url http://10.10.10.10

Permit url any

Denies HTTPS access to anywhere via port 8080.

Denies HTTP access to 10.10.10.10.

Permits access to any URL. Usually used after an ACL that denies url access.

Modes


Firewall Mode

Routed

•



—

•

Multiple

Context

—

System

—


The Cisco Secure Desktop Setup window displays the version and state of the Cisco Secure Desktop image if it is installed on the adaptive security appliance, indicates whether it is enabled, and shows the size of the cache used to hold the Cisco Secure Desktop and SSL VPN Client on the adaptive security appliance.

You can use the buttons in this window as follows:

OL-20339-01


67-7



•

•

To transfer a copy of a Cisco Secure Desktop image from your local computer to the flash device of the adaptive security appliance, click

Upload

.

To prepare to install or upgrade Cisco Secure Desktop, use your Internet browser to download a securedesktop_asa_<

n

>_<

n

>*.pkg file from http://www.cisco.com/cgi-bin/tablebuild.pl/securedesktop to any location on your PC. Then use this button to transfer a copy from your local computer to the flash device. Click

Browse Flash

to install it into the running configuration. Finally, click

Enable Secure Desktop

.

To install or replace the Cisco Secure Desktop image on the flash device of the adaptive security appliance, click

Browse Flash

.

Note

If you click

Browse Flash

to upgrade or downgrade the Cisco Secure Desktop image, select the package to install, and click

OK

, the Uninstall Cisco Secure Desktop dialog window asks you if you want to delete the Cisco Secure Desktop distribution currently in the running configuration from the flash device. Click

Yes

if you want to save space on the flash device, or click

No

to reserve the option to revert to this version of Cisco Secure Desktop.

•

To remove the Cisco Secure Desktop image and configuration file (sdesktop/data.xml) from the running configuration, click

Uninstall

.

If you click this button, the Uninstall Cisco Secure Desktop dialog window asks if you want to delete the Cisco Secure Desktop image that was named in the “Secure Desktop Image field” and all Cisco

Secure Desktop data files (including the entire Cisco Secure Desktop configuration) from the flash device. Click

Yes

if you want to remove these files from both the running configuration and the flash device, or click

No

to remove them from the running configuration, but retain them on the flash device.

Fields

The Cisco Secure Desktop Setup pane displays the following fields:

•

Location—Displays the Cisco Secure Desktop image loaded into the running configuration. By default, the filename is in the format securedesktop_asa_<n>_<n>*.pkg. Click

Browse Flash

to insert or modify the value in this field.

•

Enable Secure Desktop—Click and click

Apply

to do the following:

a.

Make sure the file is a valid Cisco Secure Desktop image.

b.

Create an “sdesktop” folder on disk0 if one is not already present.

c.

Insert a data.xml (Cisco Secure Desktop configuration) file into the sdesktop folder if one is not already present.

d.

Load the data.xml file into the running configuration.

Note

If you transfer or replace the data.xml file, disable and then enable Cisco Secure Desktop to load the file.

e.

Enable Cisco Secure Desktop.

Modes


67-8


OL-20339-01



Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Upload Image

The Upload Image dialog box lets you transfer a copy of a Cisco Secure Desktop image from your local computer to the flash device on the adaptive security appliance. Use this window to install or upgrade

Cisco Secure Desktop.

Note

Before using this window, use your Internet browser to download a securedesktop_asa_<

n

>_<

n

>*.pkg file from http://www.cisco.com/cgi-bin/tablebuild.pl/securedesktop to any location on your local computer.

You can use the buttons in this window as follows:

•

To choose the path of the securedesktop_asa_<

n

>_<

n

>*.pkg file to be transferred, click

Browse

Local Files

. The Selected File Path dialog box displays the contents of the folder you last accessed on your local computer. Navigate to the securedesktop_asa_<

n

>_<

n

>*.pkg file, select it, and click

Open

.

•

•

To select the target directory for the file, click

Browse Flash

. The Browse Flash dialog box displays the contents of the flash card.

To uploads the securedesktop_asa_<

n

>_<

n

>*.pkg file from your local computer to the flash device, click

Upload File

. A Status window appears and remains open for the duration of the file transfer.

Following the transfer, an Information window displays the message, “File is uploaded to flash successfully.” Click

OK

. The Upload Image dialog box removes the contents of the Local File Path and Flash File System Path fields.

•

To close the Upload Image dialog box, click

Close

. Click this button after you upload the Cisco

Secure Desktop image to the flash device or if you decide not to upload it. If you uploaded it, the filename appears in the Secure Desktop Image field of the Cisco Secure Desktop Setup window.

If you did not upload it, a Close Message dialog box prompts, “Are you sure you want to close the dialog without uploading the file?” Click

OK

if you do not want to upload the file. The Close

Message and Upload Image dialog boxes close, revealing the Cisco Secure Desktop Setup pane.

Otherwise, click

Cancel

in the Close Message dialog box. The dialog box closes, revealing the

Upload Image dialog box again, with the values in the fields intact. Click

Upload File

.

Fields

The Upload Image dialog box displays the following fields:

•

Local File Path—Specifies the path to the securedesktop_asa_<

n

>_<

n

>*.pkg file on your local computer. Click

Browse Local

to automatically insert the path in this field, or enter the path.

For example:

D:\Documents and Settings\

Windows_user_name

.AMER\My Documents\My

Downloads\securedesktop_asa_3_1_1_16.pkg

ASDM inserts the file path into the Local File Path field.

OL-20339-01


67-9


Configuring Application Helper

•

•

Flash File System Path—Specifies the destination path on the flash device of the adaptive security appliance and the name of the destination file. Click

Browse Flash

to automatically insert the path into this field, or enter the path. For example: disk0:/securedesktop_asa_3_1_1_16.pkg

File Name—Located in the Browse Flash dialog box that opens if you click

Browse Flash

, this field displays the name of the Cisco Secure Desktop image you selected on your local computer. We recommend that you use this name to prevent confusion. Confirm that this field displays the same name of the local file you selected and click

OK

. The Browse Flash dialog box closes. ASDM inserts the destination file path into the Flash File System Path field.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—


Clientless SSL VPN includes an Application Profile Customization Framework option that lets the adaptive security appliance handle non-standard applications and web resources so they display correctly over a clientless SSL VPN connection. An APCF profile contains a script that specifies when

(pre, post), where (header, body, request, response), and what data to transform for a particular application. The script is in XML and uses sed (stream editor) syntax to transform strings/text.

Cisco TAC may help with APCF to address specific rendering issues if the smart tunneling feature is not working or cannot be used.

You can configure multiple APCF profiles on a adaptive security appliance to run in parallel. Within an

APCF profile script, multiple APCF rules can apply. In this case, the adaptive security appliance processes the oldest rule first, based on configuration history, the next oldest rule next, and so forth.

You can store APCF profiles on the adaptive security appliance flash memory, or on an HTTP, HTTPS,

FTP, or TFTP server. Use this pane to add, edit, and delete APCF packages, and to put them in priority order.

Fields

•

APCF File Location—Displays information about the location of the APCF package. This can be on the adaptive security appliance flash memory, or on an HTTP, HTTPS, FTP, or TFTP server.

•

•

•

Add/Edit—Click to add or edit a new or existing APCF profile.

Delete—Click to remove an existing APCF profile. There is no confirmation or undo.

Move Up—Click to rearrange APCF profiles within a list. The list determines the order in which the adaptive security appliance attempts to use APCF profiles.

67-10


OL-20339-01



Add/Edit APCF Profile

This pane lets you add or edit and APCF package, which includes identifying its location, which can be either on the adaptive security appliance flash memory, or on an HTTP, HTTPS, or TFTP server.

Fields

•

Flash file—Click to locate an APCF file stored on the adaptive security appliance flash memory.

•

Path—Displays the path to an APCF file stored on flash memory after you browse to locate it. You can also manually enter the path in this field.

•

Browse Flash—Click to browse flash memory to locate the APCF file. A Browse Flash Dialog pane displays. Use the Folders and Files columns to locate the APCF file. Highlight the APCF file and click

OK.

The path to the file then displays in the Path field.

Note

If you do not see the name of an APCF file that you recently downloaded, click

Refresh

.

•

•

•

•

Upload —Click to upload an APCF file from a local computer to the adaptive security appliance flash file system. The Upload APCF package pane displays.

URL—Click to use an APCF file stored on an HTTP, HTTPS or TFTP server.

ftp, http, https, and tftp (unlabeled)—Identify the server type.

URL (unlabeled)—Enter the path to the FTP, HTTP, HTTPS, or TFTP server.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Upload APCF package

Fields

•

Local File Path—Shows the path to the APCF file on your computer. Click

Browse Local

to automatically insert the path in this field, or enter the path.

•

•

•

Browse Local Files—Click to locate and choose the APCF file on your computer that you want to transfer. The Select File Path dialog box displays the contents of the folder you last accessed on your local computer. Navigate to the APCF file, choose it, and click

Open

. ASDM inserts the file path into the Local File Path field.

Flash File System Path—Displays the path on the adaptive security appliance to upload the APCF file.

Browse Flash—Click to identify the location on the adaptive security appliance to which you want to upload the APCF file. The Browse Flash dialog box displays the contents of flash memory.

OL-20339-01


67-11


Clock Accuracy for SharePoint Access

•

•

•

•

File Name—Located in the Browse Flash dialog box that opens when you click

Browse Flash

, this field displays the name of the APCF file you selected on your local computer. We recommend that you use this name to prevent confusion. Confirm that this file displays the correct filename, and click

OK

. The Browse Flash dialog box closes. ASDM inserts the destination file path in the Flash File

System Path field.

Upload File—Click when you have identified the location of the APCF file on your computer, and the location where you want to download it to the adaptive security appliance.

A Status window appears and remains open for the duration of the file transfer. Following the transfer, an Information window displays the message, “File is uploaded to flash successfully.” Click

OK

. The Upload Image dialog window removes the contents of the Local File Path and Flash File

System Path fields, indicating you can upload another file. To do so, repeat these instructions.

Otherwise, click

Close

.

Close—Closes the Upload Image dialog window. Click this button after you upload the APCF file to flash memory or if you decide not to upload it. If you do upload it, the filename appears in the

APCF File Location field of the APCF window. If you do not upload it, a Close Message dialog box prompts, “Are you sure you want to close the dialog without uploading the file?” Click

OK

if you do not want to upload the file. The Close Message and Upload Image dialog boxes close, revealing the APCF Add/Edit pane. Otherwise, click

Cancel

in the Close Message dialog box. The dialog box closes, revealing the Upload Image dialog box again, with the values in the fields intact. Click

Upload File

.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Clock Accuracy for SharePoint Access

The clientless SSL VPN server on the adaptive security appliance uses cookies to interact with applications such as Microsoft Word on the endpoint. The cookie expiration time set by the adaptive security appliance can cause Word to malfunction when accessing documents on a SharePoint server if the time on the adaptive security appliance is incorrect. To prevent this malfunction, set the ASA clock properly. We recommend configuring the adaptive security appliance to dynamically synchronize with

NTP services. For instructions, see the “Clock Accuracy for SharePoint Access” section on page 67-12

.

Auto Signon

The Auto Signon window or tab lets you configure or edit auto signon for users of clientless SSL VPN.

Auto signon is a simplified single signon method that you can use if you do not already have an SSO method deployed on your internal network. With auto signon configured for particular internal servers, the adaptive security appliance passes the login credentials that the user of clientless SSL VPN entered to log in to the adaptive security appliance (username and password) to those particular internal servers.

You configure the adaptive security appliance to respond to a specific authentication method for a

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OL-20339-01


Auto Signon

particular range of servers. The authentication methods you can configure the adaptive security appliance to respond to consists of authentication using Basic (HTTP), NTLM, FTP and CIFS, or all of these methods.

Auto signon is a straight-forward method for configuring SSO for particular internal servers. This section describes the procedure for setting up SSO with auto signon. If you already have SSO deployed using Computer Associates SiteMinder SSO server, or if you have Security Assertion Markup Language

(SAML) Browser Post Profile SSO, and if you want to configure the adaptive security appliance to support this solution, see

SSO Servers

.

Note

Do not enable auto signon for servers that do not require authentication or that use credentials different from the adaptive security appliance. When auto signon is enabled, the adaptive security appliance passes on the login credentials that the user entered to log into the adaptive security appliance regardless of what credentials are in user storage.

Fields

•

IP Address—

Display only

. In conjunction with the following Mask, displays the IP address range of the servers to be authenticated to as configured with the Add/Edit Auto Signon dialog box. You can specify a server using either the server URI or the server IP address and mask.

•

Mask—

Display only

. In conjunction with the preceding IP Address, displays the IP address range of the servers configured to support auto signon with the Add/Edit Auto Signon dialog box.

•

•

•

•

URI—

Display only

. Displays a URI mask that identifies the servers configured with the Add/Edit

Auto Signon dialog box.

Authentication Type—

Display only

. Displays the type of authentication—Basic (HTTP), NTLM,

FTP and CIFS, or all of these methods—as configured with the Add/Edit Auto Signon dialog box.

Add/Edit—Click to add or edit an auto signon instruction. An auto signon instruction defines a range of internal servers using the auto signon feature and the particular authentication method.

Delete—Click to delete an auto signon instruction selected in the Auto Signon table.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit Auto Signon Entry

The Add/Edit Auto Signon Entry dialog box lets you add or edit a new auto signon instruction. An auto signon instruction defines a range of internal servers using the auto signon feature and the particular authentication method.

Fields

•

IP Block—Click this button to specify a range of internal servers using an IP address and mask.

–

IP Address—Enter the IP address of the first server in the range for which you are configuring auto sign-on.


OL-20339-01 67-13


Configuring Session Settings

•

•

–

Mask—From the subnet mask menu, choose the subnet mask that defines the server address range of the servers supporting auto signon.

URI—Click this button to specify a server supporting auto signon by URI, then enter the URI in the field next to this button.

Authentication Type—The authentication method assigned to the servers. For the specified range of servers, the adaptive security appliance can be configured to respond to Basic HTTP authentication requests, NTLM authentication requests, FTP and CIFS authentication requests, or requests using any of these methods.

–

–

Basic—Click this button if the servers support basic (HTTP) authentication.

NTLM—Click this button if the servers support NTLMv1 authentication.

–

–

FTP/CIFS—Click this button if the servers support FTP and CIFS authentication

Basic, NTLM, and FTP/CIFS—Click this button if the servers support all of the above.

Note

If you configure one method for a range of servers (for example, HTTP Basic) and one of those servers attempts to authenticate with a different method (for example, NTLM), the adaptive security appliance does not pass the user login credentials to that server.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Configuring Session Settings

The clientless SSL VPN Add/Edit Internal Group Policy > More Options > Session Settings window lets you specify personalized user information between clientless SSL VPN sessions. By default, each group policy inherits the settings from the default group policy. Use this window to specify personalized clientless SSL VPN user information for the default group policy and any group policies for which you want to differentiate these values.

Fields

•

User Storage Location—Click none or choose the file server protocol (smb or ftp) from the drop-down menu. If you choose smb or ftp, use the following syntax to enter the file system destination into the adjacent text field:

username

:

password

@

host

:

port-number

/

path

For example

mike:mysecret@ftpserver3:2323/public

67-14


OL-20339-01


Java Code Signer

Note

Although the configuration shows the username, password, and preshared key, the adaptive security appliance uses an internal algorithm to store the data in an encrypted form to safeguard it.

•

•

Storage Key—Type the string, if required, for the security appliance to pass to provide user access to the storage location.

Storage Objects—Choose one of the following options from the drop-down menu to specify the objects the server uses in association with the user. The adaptive security appliance store these objects to support clientless SSL VPN connections.

–

–

cookies,credentials cookies

•

–

credentials

Transaction Size-Enter the limit in KB over which to time out the session. This attribute applies only to a single transaction. Only a transaction larger than this value resets the session expiration clock.


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—


Code signing appends a digital signature to the executable code itself. This digital signature provides enough information to authenticate the signer as well as to ensure that the code has not been subsequently modified since signed.

Code-signer certificates are special certificates whose associated private keys are used to create digital signatures. The certificates used to sign code are obtained from a CA, with the signed code itself revealing the certificate origin.

Choose a Java Code Signer from the drop down list.

To configure a Java Code Signer, choose


Management > Java Code Signer

.

Content Cache

Caching enhances the performance of clientless SSL VPN. It stores frequently reused objects in the system cache, which reduces the need to perform repeated rewriting and compressing of content. The use of the cache reduces traffic, with the result that many applications run more efficiently.

Fields

•

Enable cache—Click to enable caching. The default value is disable.

OL-20339-01


67-15

Content Rewrite


•

Parameters—Lets you define the terms for caching.

–

–

Enable caching of compressed content—Click to cache compressed content. When you disable this parameter, the adaptive security appliance stores objects before it compresses them.

Maximum Object Size—Enter the maximum size in KB of a document that the adaptive security appliance can cache. The adaptive security appliance measures the original content length of the object, not rewritten or compressed content. The range is 0 to 10,000 KB; the default is 1000 KB

–

Minimum Object Size—Enter the minimum size in KB of a document that the adaptive security appliance can cache. The adaptive security appliance measures the original content length of the object, not rewritten or compressed content. The range is 0 to 10,000 KB; the default is 0 KB.

Note

The Maximum Object Size must be greater than the Minimum Object Size.

•

–

–

Expiration Time—Enter an integer between 0 and 900 to set the number of minutes to cache objects without revalidating them. The default is one minute.

LM Factor—Enter an integer between 1 and 100; the default is 20.

The LM factor sets the policy for caching objects which have only the last-modified timestamp.

This revalidates objects that have no server-set change values. The adaptive security appliance estimates the length of time since the object has changed, also called the expiration time. The estimated expiration time equals the time elapsed since the last change multiplied by the LM factor. Setting the LM factor to 0 forces immediate revalidation, while setting it to 100 results in the longest allowable time until revalidation.

The expiration time sets the amount of time to for the adaptive security appliance to cache objects that have neither a last-modified time stamp nor an explicit server-set expiry time.

–

Cache static content—Click to cache all content that is not subject to rewrite, for example, PDF files and images.

Restore Cache Default—Click to restore default values for all cache parameters.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Content Rewrite

The Content Rewrite pane lists all applications for which content rewrite is enabled or disabled.

Clientless SSL VPN processes application traffic through a content transformation/rewriting engine that includes advanced elements such as JavaScript, VBScript, Java, and multi-byte characters to proxy

HTTP traffic which may have different semantics and access control rules depending on whether the user is using an application within or independently of an SSL VPN device.

67-16


OL-20339-01


Content Rewrite

By default, the security appliance rewrites, or transforms, all clientless traffic. You might not want some applications and web resources (for example, public websites) to go through the adaptive security appliance. The adaptive security appliance therefore lets you create rewrite rules that let users browse certain sites and applications without going through the adaptive security appliance. This is similar to split-tunneling in an IPSec VPN connection.

You can create multiple rewrite rules. The rule number is important because the security appliance searches rewrite rules by order number, starting with the lowest, and applies the first rule that matches.

“

Example Content Rewrite Rules ” shows example content rewrite rules.

Fields

•

Content Rewrite

–

–

Rule Number—Displays an integer that indicates the position of the rule in the list.

Rule Name—Provides the name of the application for which the rule applies.

•

•

–

–

Rewrite Enabled—Displays content rewrite as enabled or disabled.

Resource Mask—Displays the resource mask.

Add/Edit—Click to add a rewrite entry or edit a selected rewrite entry.

Delete—Click to delete a selected rewrite entry.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit Content Rewrite Rule

•

Enable content rewrite—Click to enable content rewrite for this rewrite rule.

•

•

Rule Number—(Optional) Enter a number for this rule. This number specifies the priority of the rule, relative to the others in the list. Rules without a number are at the end of the list. The range is

1 to 65534.

Rule Name—(Optional) Provide an alphanumeric string that describes the rule, maximum 128 characters.

•

Resource Mask—Enter a string to match the application or resource to apply the rule to. The string can be up to 300 characters. You can use one of the following wildcards, but you must specify at least one alphanumeric character.

* — Matches everything. ASDM does not accept a mask that consists of a * or *.*

? —Matches any single character.

[!seq] — Matches any character not in sequence.

[seq] — Matches any character in sequence.

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67-17



Example Content Rewrite Rules

Table 67-1

Function

Force all HTTP URLs to be delivered outside of ASA

(split-tunneling)

Force all HTTPS URLs to be delivered outside of ASA

Enable content rewrite

Check

Check

Rule

Number

1

2

Rule Name Resource Mask

split-tunnel-all-http http://* split-tunnel-all-https https://*

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—


Java objects which have been transformed by clientless SSL VPN can subsequently be signed using a

PKCS12 digital certificate associated with a trustpoint. In the Java Trustpoint pane, you can configure the clientless SSL VPN Java object signing facility to use a PKCS12 certificate and keying material from a specified trustpoint location. To import a trustpoint, choose

Configuration > Properties > Certificate

> Trustpoint > Import

.

Fields

•

Code Signer Certificate—Choose the configured certificate that you want to employ in Java object signing.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Encoding

This pane lets you view or specify the character encoding for clientless SSL VPN portal pages.

67-18


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Encoding

Character encoding

, also called “character coding” and “a character set,” is the pairing of raw data (such as 0s and 1s) with characters to represent the data. The language determines the character encoding method to use. Some languages use a single method, while others do not. Usually, the geographic region determines the default encoding method used by the browser, but the remote user can change it. The browser can also detect the encoding specified on the page, and render the document accordingly.

The encoding attribute lets you specify the value of the character-encoding method used on the portal page to ensure that the browser renders it properly, regardless of the region in which the user is using the browser, and regardless of any changes made to the browser.

By default, the adaptive security appliance applies the “Global Encoding Type” to pages from Common

Internet File System servers. The mapping of CIFS servers to their appropriate character encoding, globally with the “Global Encoding Type” attribute, and individually with the file-encoding exceptions displayed in the table, provides for the accurate handling and display of CIFS pages when the proper rendering of filenames or directory paths, as well as pages, is an issue.

Fields

•

Global Encoding Type —This attribute determines the character encoding that all clientless SSL

VPN portal pages inherit except for those from the CIFS servers listed in the table. You can type the string or choose one of the options from the drop-down list, which contains the most common values, as follows:

–

–

big5 gb2312

–

–

–

ibm-850 iso-8859-1 shift_jis

Note

If you are using Japanese Shift_jis Character encoding, click

Do not specify

in the Font

Family area of the associated Select Page Font pane to remove the font family.

•

•

•

•

–

–

–

unicode windows-1252 none

If you click

none

or specify a value that the browser on the clientless SSL VPN session does not support, it uses its own default encoding.

You can type a string consisting of up to 40 characters, and equal to one of the valid character sets identified in http://www.iana.org/assignments/character-sets . You can use either the name or the alias of a character set listed on that page. The string is case-insensitive. The command interpreter converts upper-case to lower-case when you save the adaptive security appliance configuration.

CIFS Server—Name or IP address of each CIFS server for which the encoding requirement differs from the “Global Encoding Type” attribute setting.

A difference in the encoding of the CIFS server filename and directory indicates that you might need to add an entry for the server to ensure the encoding is correct.

Encoding Type—Displays the character encoding override for the associated CIFS server.

Add—Click once for each CIFS server for which you want to override the “Global Encoding Type” setting.

Edit—Select a CIFS server in the table and click this button to change its character encoding.

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67-19

Encoding


•

Delete—Select a CIFS server in the table and click this button to delete the associated entry from the table.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add\Edit Encoding

67-20

The Add CIFS Server Encoding dialog box lets you maintain exceptions to the “Global Encoding Type” attribute setting in the Add CIFS Encoding window. That pane contains the Add and Edit buttons that open this dialog box.

Fields

•

CIFS Server—Enter the name or IP address of a CIFS server for which the encoding requirement differs from the “Global Encoding Type” attribute setting. The adaptive security appliance retains the case you specify, although it ignores the case when matching the name to a server.

•

Encoding Type—Choose the character encoding that the CIFS server should provide for clientless

SSL VPN portal pages. You can type the string, or choose one from the drop-down list, which contains only the most common values, as follows:

–

–

big5 gb2312

–

–

ibm-850 iso-8859-1

–

shift_jis

Note

If you are using Japanese Shift_jis Character encoding, click

Do not specify

in the Font

Family area of the associated Select Page Font pane to remove the font family.

–

–

unicode windows-1252

–

none

If you click

none

or specify a value that the browser on the clientless SSL VPN session does not support, it uses its own default encoding.

You can type a string consisting of up to 40 characters, and equal to one of the valid character sets identified in http://www.iana.org/assignments/character-sets . You can use either the name or the alias of a character set listed on that page. The string is case-insensitive. The command interpreter converts upper-case to lower-case when you save the adaptive security appliance configuration.

Modes



OL-20339-01


Web ACLs

Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Web ACLs

The Web ACLs table displays the filters configured on the adaptive security appliance applicable to clientless SSL VPN traffic. The table shows the name of each access control list (ACL), and below and indented to the right of the ACL name, the ACEs (access control entries) assigned to the ACL.

Each ACL permits or denies access permits or denies access to specific networks, subnets, hosts, and web servers. Each ACE specifies one rule that serves the function of the ACL.

You can configure ACLs to apply to clientless SSL VPN traffic. The following rules apply:

•

If you do not configure any filters, all connections are permitted.

•

•


At the end of each ACL, an implicit, unwritten rule denies all traffic that is not explicitly permitted.

You can add ACLs and ACEs as follows:

•

To add an ACL, click the down arrow next to the plus sign above the table and click

Add ACL

.

Note

An ACL must be present before you can add an ACE.

•

•

To add an ACE to an ACL that is already present in the table, choose it, then click the down arrow next to the plus sign above the table and click

Add ACE

.

To insert an ACE before an ACE that is already present in the table, choose it, then click the down arrow next to the plus sign above the table and click

Insert

.

•

To insert an ACE after an ACE that is already present in the table, choose it, then click the down arrow next to the plus sign above the table and click

Insert After

.

To change the values assigned to an ACE, double-click it, or choose it and click

Edit

.

To remove an ACL or an ACE, choose the entry in the table and click

Delete

.

The relative position of an ACE in an ACL determines the sequence with which the adaptive security appliance applies it to traffic on the interface. You can reorganize and reuse the ACEs present in the table as follows.

•

To move an ACE above or below another ACE, choose it and click the up or down icon above the table.

•

To move an ACE, choose the ACE, click the scissors icon above the table. Select the target ACL or

ACE, click the arrow next to the clipboard icon, and click

Paste

to paste above the selection or

Paste

After

to paste after the selection. The Edit ACE dialog box opens, providing you with an opportunity to change the values. Click

OK

.

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67-21


Configuring Port Forwarding

•

To copy an ACE, choose it and click the double-page icon above the table. Choose the target ACL or ACE, click the arrow next to the clipboard icon, and click

Paste

to paste above the selection or

Paste After

to paste after the selection. The Edit ACE dialog box opens, providing you with an opportunity to change the values. Click

OK

.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—


Both the Port Forwarding pane and Configure Port Forwarding Lists dialog box let you view the port forwarding lists. Both the Port Forwarding pane and the Add or Edit Port Forwarding Entry dialog box let you specify the name of a port forwarding list, and add, view, edit, and delete port forwarding entries to the list.

To add, change, or remove a port forwarding list, do one of the following:

•

To add a port forwarding list and add entries to it, click

Add

. The Add Port Forwarding List dialog box opens. After you name the list, click

Add

again. ASDM opens the Add Port Forwarding Entry dialog box, which lets you assign the attributes of an entry to the list. After doing so and clicking

OK, ASDM displays those attributes in the list. Repeat as needed to complete the list, then click

OK

in the Add Port Forwarding List dialog box.

•

•

To change a port forwarding list, double-click the list or choose the list in the table and click

Edit

.

Then click

Add

to insert a new entry into the list, or click an entry in the list and click

Edit

or

Delete

.

To remove a list, select the list in the table and click

Delete

.

Why Port Forwarding?

Port forwarding is the legacy technology for supporting TCP-based applications over a clientless SSL

VPN connection. You may choose to use port forwarding because you have built earlier configurations that support this technology.

Please consider the following alternatives to port forwarding:

•

•

Smart tunnel access offers the following advantages to users:

–

Smart tunnel offers better performance than plug-ins.

–

–

Unlike port forwarding, smart tunnel simplifies the user experience by not requiring the user connection of the local application to the local port.

Unlike port forwarding, smart tunnel does not require users to have administrator privileges.

Unlike port forwarding and smart tunnel access, a plug-in does not require the client application to be installed on the remote computer.

67-22


OL-20339-01



When configuring port forwarding on the adaptive security appliance, you specify the port the application uses. When configuring smart tunnel access, you specify the name of the executable file or its path.

Port Forwarding Requirements and Restrictions

In addition to the requirements in the

“Understanding Clientless SSL VPN System Requirements” section on page 67-3 , the following requirements and limitations apply to smart tunnel access on

Windows:

•

The remote host must be running a 32-bit version of one of the following:

–

–

Microsoft Windows Vista and Windows XP SP2 or SP3.

Apple Mac OS X 10.5 with Safari 2.0.4(419.3).

•

–

Fedora Core 4

Browser-based users of Safari on Mac OS X 10.5.3 must identify a client certificate for use with the

URL of the adaptive security appliance, once with the trailing slash and once without it, because of the way Safari interprets URLs. For example,

–

–

https://example.com/ https://example.com

•

•

•

•

•

•

•

For details, go to the Safari, Mac OS X 10.5.3: Changes in client certificate authentication .

Users of Microsoft Windows Vista who use port forwarding or smart tunnels must add the URL of the ASA to the Trusted Site zone. To access the Trusted Site zone, they must start Internet Explorer and choose the

Tools > Internet Options > Security

tab. Vista users can also disable Protected

Mode to facilitate smart tunnel access; however, we recommend against this method because it increases the computer’s vulnerability to attack.

Port forwarding supports only TCP applications that use static TCP ports. Applications that use dynamic ports or multiple TCP ports are not supported. For example, SecureFTP, which uses port

22, works over clientless SSL VPN port forwarding, but standard FTP, which uses ports 20 and 21, does not.

Port forwarding does not support protocols that use UDP.

The security appliance does not support the Microsoft Outlook Exchange (MAPI) proxy. For

Microsoft Outlook Exchange communication using the MAPI protocol, remote users must use

AnyConnect.

A stateful failover does not retain sessions established using Application Access (either port forwarding or smart tunnel access). Users must reconnect following a failover.

Port forwarding does not support connections to personal digital assistants.

Port forwarding requires Sun JRE 5, Update 1.4 or later (JRE 6 or later recommended) to be enabled on the browser.

Caution

If JRE 1.4.x is running and the user authenticates with a digital certificate, the application fails to start because JRE cannot access the web browser certificate store.

•

Because port forwarding requires downloading the Java applet and configuring the local client, and because doing so requires administrator permissions on the local system, it is unlikely that users will be able to use applications when they connect from public remote systems.

OL-20339-01


67-23



•

•

The Java applet displays in its own window on the end user HTML interface. It shows the contents of the list of forwarded ports available to the user, as well as which ports are active, and amount of traffic in bytes sent and received.

Neither port forwarding nor the ASDM Java applet work with user authentication using digital certificates. Java does not have the ability to access the web browser keystore. Therefore Java cannot use certificates that the browser uses to authenticate users, and the application cannot start.

The port forwarding applet displays the local port and the remote port as the same when the local IP address 127.0.0.1 is being used and cannot be updated by the clientless SSL VPN connection from the ASA. As a result, the ASA creates new IP addresses 127.0.0.2, 127.0.0.3, and so on for local proxy IDs. Because you can modify the hosts file and use different loopbacks, the remote port is used as the local port in the applet. To connect, you can use Telnet with the host name, without specifying the port. The corect local IP addresses are available in the local hosts file.

Configuring DNS for Port Forwarding

Port Forwarding forwards the domain name of the remote server or its IP address to the ASA for resolution and connection. In other words, the port forwarding applet accepts a request from the application and forwards it to the ASA. The ASA makes the appropriate DNS queries and establishes the connection on behalf of the port forwarding applet. The port forwarding applet only makes DNS queries to the ASA. It updates the host file so that when a port forwarding application attempts a DNS query, the query redirects to a loopback address.

Configure the adaptive security appliance to accept the DNS requests from the port forwarding applet as follows:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Click

Configuration

>


>


>

Connection Profiles

.

The DefaultWEBVPNGroup entry is the default connection profile used for clientless connections.

Highlight the DefaultWEBVPNGroup entry, then click

Edit

if your configuration uses it for clientless connections. Otherwise, highlight a connection profile used in your configuration for clientless connections, then click

Edit

.

The Basic window opens.

Scan to the DNS area and select the DNS server from the drop-down list. Note the domain name, disregard the remaining steps, and go to the next section if ASDM displays the DNS server you want to use. You need to enter the same domain name when you specify the remote server while configuring an entry in the port forwarding list. Continue with the remaining steps if the DNS server is not present in the configuration.

Click

Manage

in the DNS area.

The Configure DNS Server Groups window opens.

Click

Configure Multiple DNS Server Groups

.

A window displays a table of DNS server entries.

Click

Add.

The Add DNS Server Group window opens.

Enter a new server group name in the Name field, and enter the IP address and domain name (see

Figure 67-3

)

67-24


OL-20339-01


Figure 67-3 Example DNS Server Values for Port Forwarding


OL-20339-01

Step 8

Step 9

Step 10

Note the domain name you entered. You need it when you specify the remote server later while configuring a port forwarding entry.

Click

OK

until the Connection Profiles window becomes active again.

Repeat Steps

2

–

8 for each remaining connection profile used in your configuration for clientless

connections.

Click

Apply

.


67-25


Modes



Firewall Mode

Routed


Multiple


• • • •

System

—

Add/Edit Port Forwarding List

The Add/Edit Port Forwarding List dialog boxes let you add or edit a named list of TCP applications to associate with users or group policies for access over clientless SSL VPN connections.

Fields

•

List Name—Alpha-numeric name for the list. Maximum 64 characters.

•

Local TCP Port—Local port that listens for traffic for the application.

•

•

•

Remote Server—IP address or DNS name of the remote server.

Remote TCP Port—Remote port that listens for traffic for the application.

Description—Text that describes the TCP application.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit Port Forwarding Entry

The Add/Edit Port Forwarding Entry dialog boxes let you specify TCP applications to associate with users or group policies for access over clientless SSL VPN connections. Assign values to the attributes in these windows as follows:

•

•

Local TCP Port—Type a TCP port number for the application to use. You can use a local port number only once for a listname. To avoid conflicts with local TCP services, use port numbers in the range 1024 to 65535.

Remote Server—Enter either the domain name or IP address of the remote server. We recommend using a domain name so that you do not have to configure the client applications for the specific IP address.

67-26


OL-20339-01


Configuring the Use of External Proxy Servers

Caution

The DNS name assigned to the Remote Server parameter must match the Domain Name and

Server Group parameters to establish the tunnel and resolve to an IP address, per the

instructions in Add/Edit Port Forwarding List, page 67-26

. The default setting for both the

Domain and Server Group parameters is DefaultDNS.

•

•

Remote TCP Port—Type the well-know port number for the application.

Description—Type a description of the application. Maximum 64 characters.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Configuring the Use of External Proxy Servers

Use the Proxies pane to configure the adaptive security appliance to use external proxy servers to handle

HTTP requests and HTTPS requests. These servers act as an intermediary between users and the

Internet. Requiring all Internet access via servers you control provides another opportunity for filtering to assure secure Internet access and administrative control.

Note

HTTP and HTTPS proxy services do not support connections to personal digital assistants.

Fields

Use an HTTP proxy server—Click to use an external HTTP proxy server.

•

•

•

Specify IP address of proxy server—Click to identify the HTTP proxy server by its IP address or hostname.

IP Address—Enter the hostname or IP address of the external HTTP proxy server.

•

Port—Enter the port that listens for HTTP requests. The default port is 80.

Exception Address List— (Optional) Enter a URL or a comma-delimited list of several URLs to exclude from those that can be sent to the HTTP proxy server. The string does not have a character limit, but the entire command cannot exceed 512 characters. You can specify literal URLs or use the following wildcards:

–

–

–

–

*

to match any string, including slashes (/) and periods (.). You must accompany this wildcard with an alphanumeric string.

?

to match any single character, including slashes and periods.

[

x

-

y

] to match any single character in the range of

x

and

y

, where

x

represents one character and

y

represents another character in the ANSI character set.

[

!

x

-

y

] to match any single character that is not in the range.

OL-20339-01


67-27


Configuring Proxy Bypass

•

•

•

•

•

UserName—(Optional) Enter this keyword to accompany each HTTP proxy request with a username to provide basic, proxy authentication.

Password—Enter a password to send to the proxy server with each HTTP request.

Specify PAC file URL—As an alternative to specifying the IP address of the HTTP proxy server, you can choose this option to specify a Proxy autoconfiguration file to download to the browser.

Once downloaded, the PAC file uses a JavaScript function to identify a proxy for each URL. Enter

http://

and type the URL of the proxy autoconfiguration file into the adjacent field. If you omit the

http://

portion, the adaptive security appliance ignores it.

Use an HTTPS proxy server—Click to use an external HTTPS proxy server.

•

Specify IP address of proxy server—Click to identify the HTTPS proxy server by its IP address or hostname.

•

•

•

IP Address—Enter the hostname or IP address of the external HTTPS proxy server

Port—Enter the port that listens for HTTPS requests. The default port is 443.

Exception Address List— (Optional) Enter a URL or a comma-delimited list of several URLs to exclude from those that can be sent to the HTTPS proxy server. The string does not have a character limit, but the entire command cannot exceed 512 characters. You can specify literal URLs or use the following wildcards:

–

*

to match any string, including slashes (/) and periods (.). You must accompany this wildcard with an alphanumeric string.

–

–

?

to match any single character, including slashes and periods.

[

x

-

y

] to match any single character in the range of

x

and

y

, where

x

represents one character and

y

represents another character in the ANSI character set.

–

[

!

x

-

y

] to match any single character that is not in the range.

UserName—(Optional) Enter this keyword to accompany each HTTPS proxy request with a username to provide basic, proxy authentication.

Password—Enter a password to send to the proxy server with each HTTPS request.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—


You can configure the adaptive security appliance to use proxy bypass when applications and web resources work better with the special content rewriting this feature provides. Proxy bypass is an alternative method of content rewriting that makes minimal changes to the original content. It is often useful with custom web applications.

You can configure multiple proxy bypass entries. The order in which you configure them is unimportant.

The interface and path mask or interface and port uniquely identify a proxy bypass rule.

67-28


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If you configure proxy bypass using ports rather than path masks, depending on your network configuration, you might need to change your firewall configuration to allow these ports access to the adaptive security appliance. Use path masks to avoid this restriction. Be aware, however, that path masks can change, so you might need to use multiple pathmask statements to exhaust the possibilities.

A path is the text in a URL that follows the domain name. For example, in the URL www.example.com/hrbenefits,

hrbenefits

is the path. Similarly, for the URL www.example.com/hrinsurance,

hrinsurance

is the path. If you want to use proxy bypass for all hr sites, you can avoid using the command multiple times by using the * wildcard as follows: /hr*.

Fields

•

Interface—Displays the VLAN configured for proxy bypass.

•

Port—Displays the port configured for proxy bypass.

•

•

•

•

•

Path Mask—Displays the URI path to match for proxy bypass.

URL—Displays the target URLs.

Rewrite—Displays the rewrite options. These are a combination of XML, link, or none.

Add/Edit—Click to add a proxy bypass entry or edit a selected entry.

Delete—Click to delete a proxy bypass entry.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add/Edit Proxy Bypass Rule

This pane lets you set rules for when the adaptive security appliance performs little or no content rewriting.

Fields

•

Interface Name—Select the VLAN for proxy bypass.

•

Bypass Condition—Specify either a port or a URI for proxy bypass.

–

–

Port—(radio button) Click to use a port for proxy bypass. The valid port numbers are

20000-21000.

Port (field)—Enter a high-numbered port for the adaptive security appliance to reserve for proxy bypass.

•

–

–

Path Mask—(radio button) Click to use a URL for proxy bypass.

Path Mask—(Field) Enter a URL for proxy bypass. It can contain a regular expression.

URL—Define target URLs for proxy bypass.

–

URL—(drop-down list) Click either http or https as the protocol.

–

URL (text field)—Enter a URL to which you want to apply proxy bypass.

OL-20339-01


67-29

SSO Servers


•

Content to Rewrite—Specifies the content to rewrite. The choices are none or a combination of

XML, links, and cookies.

–

–

XML—Check to rewrite XML content.

Hostname—Check to rewrite links.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

SSO Servers

The SSO Server pane lets you configure or delete single sign-on (SSO) for users of clientless SSL VPN connecting to a Computer Associates SiteMinder SSO server or to a Security Assertion Markup

Language (SAML), Version 1.1, Browser Post Profile SSO server. SSO support, available only for clientless SSL VPN, lets users access different secure services on different servers without entering a username and password more than once.

You can choose from four methods when configuring SSO: Auto Signon using basic HTTP and/or

NTLMv1 authentication, HTTP Form protocol, or Computer Associates eTrust SiteMinder (formerly

Netegrity SiteMinder), or SAML, Version 1.1 Browser Post Profile.

Note

The SAML Browser Artifact profile method of exchanging assertions is not supported.

The following sections describe the procedures for setting up SSO with both SiteMinder and SAML

Browser Post Profile.

•

Auto Signon —configures SSO with basic HTTP or NTLM authentication.

•

Configuring Session Settings

—configures SSO with the HTTP Form protocol.

The SSO mechanism either starts as part of the AAA process (HTTP Forms) or just after successful user authentication to either a AAA server (SiteMinder) or a SAML Browser Post Profile server. In these cases, the clientless SSL VPN server running on the adaptive security appliance acts as a proxy for the user to the authenticating server. When a user logs in, the clientless SSL VPN server sends an SSO authentication request, including username and password, to the authenticating server using HTTPS.

If the authenticating server approves the authentication request, it returns an SSO authentication cookie to the clientless SSL VPN server. This cookie is kept on the adaptive security appliance on behalf of the user and used to authenticate the user to secure websites within the domain protected by the SSO server.

67-30


OL-20339-01


SSO Servers

Configuring SiteMinder and SAML Browser Post Profile

SSO authentication with SiteMinder or with SAML Browser Post Profile is separate from AAA and occurs after the AAA process completes. To set up SiteMinder SSO for a user or group, you must first configure a AAA server (RADIUS, LDAP and so forth). After the AAA server authenticates the user, the clientless SSL VPN server uses HTTPS to send an authentication request to the SiteMinder SSO server.

In addition to configuring the adaptive security appliance, for SiteMinder SSO, you also must configure your CA SiteMinder Policy Server with the Cisco authentication scheme. See

Adding the Cisco

Authentication Scheme to SiteMinder

.

For SAML Browser Post Profile you must configure a Web Agent (Protected Resource URL) for authentication. For the specifics of setting up a SAML Browser Post Profile SSO server, see

SAML

POST SSO Server Configuration .

Fields

•

Server Name

—Display only.

Displays the names of configured SSO Servers. The minimum number of characters is 4, and the maximum is 31.

•

Authentication Type

—Display only.

Displays the type of SSO server. The adaptive security appliance currently supports the SiteMinder type and the SAML Browser Post Profile type.

•

•

•

•

•

•

URL

—Display only.

Displays the SSO server URL to which the adaptive security appliance makes

SSO authentication requests.

Secret Key

—Display only.

Displays the secret key used to encrypt authentication communications with the SSO server. The key can be comprised of any regular or shifted alphanumeric character.

There is no minimum or maximum number of characters.

Maximum Retries

—Display only.

Displays the number of times the adaptive security appliance retries a failed SSO authentication attempt. The range is 1 to 5 retries, and the default number of retries is 3.

Request Timeout (seconds)

—Display only.

Displays the number of seconds before a failed SSO authentication attempt times out. The range is 1 to 30 seconds, and the default number of seconds is

5.

Add/Edit—Opens the Add/Edit SSO Server dialog box.

Delete—Deletes the selected SSO server.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

SAML POST SSO Server Configuration

Use the SAML server documentation provided by the server software vendor to configure the SAML server in Relying Party mode. To configure the SAML Server for Browser Post Profile, perform the following steps:


OL-20339-01 67-31


SSO Servers

Step 1

Step 2

Step 3

Step 4

Configure the SAML server parameters to represent the asserting party (the adaptive security appliance):

•

•

Recipient consumer (Web Agent) URL (same as the assertion consumer URL configured on the

ASA)

Issuer ID, a string, usually the hostname of appliance

•

Profile type -Browser Post Profile

Configure certificates.

Specify that asserting party assertions must be signed.

Select how the SAML server identifies the user:

•

•

Subject Name Type is DN

Subject Name format is uid=<user>

Adding the Cisco Authentication Scheme to SiteMinder

Besides configuring the adaptive security appliance for SSO with SiteMinder, you must also configure your CA SiteMinder Policy Server with the Cisco authentication scheme, provided as a Java plug-in.

Note •

•

•

Configuring the SiteMinder Policy Server requires experience with SiteMinder.

This section presents general tasks, not a complete procedure.

Refer to the CA SiteMinder documentation for the complete procedure for adding a custom authentication scheme.

To configure the Cisco authentication scheme on your SiteMinder Policy Server, perform the following steps:

Step 1

Step 2

With the Siteminder Administration utility, create a custom authentication scheme being sure to use the following specific arguments:

•

In the Library field, enter

smjavaapi

.

•

In the Secret field, enter the same secret configured in the Secret Key field of the Add SSO Server dialog to follow.

In the Parameter field, enter

CiscoAuthApi

.

•

Using your Cisco.com login, download the file

cisco_vpn_auth.jar

from http://www.cisco.com/cgi-bin/tablebuild.pl/asa and copy it to the default library directory for the

SiteMinder server. This .jar file is also available on the Cisco adaptive security appliance CD.

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Configuring Smart Tunnel Access

Add/Edit SSO Servers

This SSO method uses CA SiteMinder and SAML Browser Post Profile. You can also set up SSO using the HTTP Form protocol, or Basic HTML and NTLM authentication. To use the HTTP Form protocol,

see Configuring Session Settings

. To set use basic HTML or NTLM authentication, use the

auto-signon

command at the command line interface.

Fields

•

Server Name—If adding a server, enter the name of the new SSO server. If editing a server, this field is display only; it displays the name of the selected SSO server.

•

Authentication Type

—Display only.

Displays the type of SSO server. The types currently supported by the adaptive security appliance are SiteMinder and SAML Browser Post Profile.

•

•

•

•

URL—Enter the SSO server URL to which the adaptive security appliance makes SSO authentication requests.

Secret Key—Enter a secret key used to encrypt authentication requests to the SSO server. Key characters can be any regular or shifted alphanumeric characters. There is no minimum or maximum number of characters. The secret key is similar to a password: you create it, save it, and configure it. It is configured on the adaptive security appliance, the SSO server, and the SiteMinder Policy

Server using the Cisco Java plug-in authentication scheme.

Maximum Retries—Enter the number of times the adaptive security appliance retries a failed SSO authentication attempt before the authentication times-out. The range is from 1 to 5 retries inclusive, and the default is 3 retries.

Request Timeout—Enter the number of seconds before a failed SSO authentication attempt times out. The range is from1 to 30 seconds inclusive, and the default is 5 seconds.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—


The Smart Tunnels table displays the smart tunnel lists, each of which identifies one or more applications eligible for smart tunnel access, and its associated operating system. Because each group policy or local user policy supports one smart tunnel list, you must group the nonbrowser-based applications to be supported into a smart tunnel list. You can also specify which group policy homepage can use smart tunnel (with the use-smart-tunnel CLI command or on the Configuration > Remote Access VPN >

Clientless SSL VPN Access > Group Policies > Edit > Edit Internal Group Policy of the GUI). Following the configuration of a list, you can assign it to one or more group policies or local user policies. The internal company resources are accessed through the VPN gateway, but smart tunnel allows direct

Internet access without going through the VPN gateway.

The Configuration > Remote Access VPN > Clientless SSL VPN Access > Portal > Smart Tunnels window lets you do the following:

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•

•

To add a smart tunnel list and add applications to the list, click

Add

. The Add Smart Tunnel List dialog box opens. After you name the list, click

Add

again. ASDM opens the Add Smart Tunnel

Entry dialog box, which lets you assign the attributes of a smart tunnel to the list. After doing so and clicking OK, ASDM displays those attributes in the list. Repeat as needed to complete the list, then click

OK

in the Add Smart Tunnel List dialog box.

To change a smart tunnel list, double-click the list or choose the list in the table and click

Edit

. Then click

Add

to insert a new set of smart tunnel attributes into the list, or choose an entry in the list and click

Edit

or

Delete

.

To remove a list, choose the list in the table and click

Delete

.

•

•

To specify logoff procedures for a VPN session, choose one of the following options:

–

If you enable the

Click on smart-tunnel logoff icon in the system tray

radio button, a notification icon appears in the system tray when smart tunnel is started. You can use the icon to log off a VPN session. If you select this option, the VPN session persists even when all browser windows have been closed. This option enables you to gain clientless SSL VPN access from a browser, start an application (such as terminal service client), and then close the browser.

–

If the

Logoff smart-tunnel when its parent process, such as a browser, terminates

radio button is enabled, you are logged off after all browser windows have been closed.

Following the configuration and assignment of a smart tunnel list, you can make a smart tunnel easy to use by adding a bookmark for the service and clicking the

Enable Smart Tunnel Option

in the Add or

Edit Bookmark dialog box (Portal > Bookmarks). You can create a bookmark independent of whether you created a smart tunnel application list (as long as your bookmark page does not use a non-browser application such as JAVA).

About Smart Tunnels

A smart tunnel is a connection between a TCP-based application and a private site, using a clientless

(browser-based) SSL VPN session with the security appliance as the pathway, and the adaptive security appliance as a proxy server. You can identify applications to which you want to grant smart tunnel access and specify the local path to each application. For applications running on Microsoft Windows, you can also require a match of the SHA-1 hash of the checksum as a condition for granting smart tunnel access.

Lotus SameTime and Microsoft Outlook Express are examples of applications to which you might want to grant smart tunnel access.

Configuring smart tunnels requires one of the following procedures, depending on whether the application is a client or is a web-enabled application:

•

Create one or more smart tunnel lists of the client applications, then assign the list to the group policies or local user policies for whom you want to provide smart tunnel access.

•

Create one or more bookmark list entries that specify the URLs of the web-enabled applications eligible for smart tunnel access, then assign the list to the DAPs, group policies, or local user policies for whom you want to provide smart tunnel access.

You can also list web-enabled applications for which to automate the submission of login credentials in smart tunnel connections over clientless SSL VPN sessions.

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Why Smart Tunnels?

Smart tunnel access lets a client TCP-based application use a browser-based VPN connection to connect to a service. It offers the following advantages to users, compared to plug-ins and the legacy technology, port forwarding:

•

Smart tunnel offers better performance than plug-ins.

•

Unlike port forwarding, smart tunnel simplifies the user experience by not requiring the user connection of the local application to the local port.

Unlike port forwarding, smart tunnel does not require users to have administrator privileges.

•

The advantage of a plug-in is that it does not require the client application to be installed on the remote computer.

Smart Tunnel Requirements and Limitations

The following sections categorize the smart tunnel requirements and limitations.

General Requirements and Limitations

Smart tunnel has the following general requirements and limitations:

•

Smart tunnel auto sign-on supports only Microsoft Internet Explorer on Windows.

•

•

The browser must be enabled with Java, Microsoft ActiveX, or both.

Smart tunnel supports only proxies placed between computers running Microsoft Windows and the security appliance. Smart tunnel uses the Internet Explorer configuration (that is, the one intended for system-wide use in Windows). If the remote computer requires a proxy server to reach the adaptive security appliance, the URL of the terminating end of the connection must be in the list of

URLs excluded from proxy services. If the proxy configuration specifies that traffic destined for the

ASA goes through a proxy, all smart tunnel traffic goes through the proxy.

•

•

•

In an HTTP-based remote access scenario, sometimes a subnet does not provide user access to the

VPN gateway. In this case, a proxy placed in front of the ASA to route traffic between the web and the end user's location provides web access. However, only VPN users can configure proxies placed in front of the ASA. When doing so, they must make sure these proxies support the CONNECT method. For proxies that require authentication, smart tunnel supports only the basic digest authentication type.

When smart tunnel starts, the adaptive security appliance by default passes all browser traffic through the VPN session if the browser process is the same. The adaptive security appliance also does this if a tunnel-all policy applies. If the user starts another instance of the browser process, it passes all traffic through the VPN session. If the browser process is the same and the security appliance does not provide access to a URL, the user cannot open it. As a workaround, assign a tunnel policy that is not tunnel-all.

A stateful failover does not retain smart tunnel connections. Users must reconnect following a failover.

If it takes too long for smart tunnel to load, perform the following:

–

–

Clear the SSL state (with Internet Explorer, go to

Tools > Internet Options > Content

).

Disable the

Check for server certificate revocation

check box (with Internet Explorer, go to

Tools > Internet Options > Advanced > Security)

.

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–

Delete cookies (with Internet Explorer, go to

Tools > Internet Options > General

).

Windows Requirements and Limitations

In addition to the requirements in Understanding Clientless SSL VPN System Requirements, page 67-3

, the following requirements and limitations apply to smart tunnel access on Windows:

•

ActiveX or Sun JRE 5, Update 1.4 or later (JRE 6 or later recommended) on Windows must be enabled on the browser.

•

•

Only Winsock 2, TCP-based applications are eligible for smart tunnel access.

The security appliance does not support the Microsoft Outlook Exchange (MAPI) proxy. Neither port forwarding nor the smart tunnel supports MAPI. For Microsoft Outlook Exchange communication using the MAPI protocol, remote users must use AnyConnect.

•

Users of Microsoft Windows Vista who use smart tunnel or port forwarding must add the URL of the ASA to the Trusted Site zone. To access the Trusted Site zone, they must start Internet Explorer and choose the

Tools > Internet Options > Security

tab. Vista users can also disable Protected

Mode to facilitate smart tunnel access; however, we recommend against this method because it increases vulnerability to attack.

Mac OS Requirements and Limitations

In addition to the requirements in Understanding Clientless SSL VPN System Requirements, page 67-3

, the following requirements and limitations apply to smart tunnel access on Mac OS:

•

Smart tunnel supports Mac OS running on an Intel processor only.

•

•

Java Web Start must be enabled on the browser.

Only applications started from the portal page can establish smart tunnel connections. This requirement includes smart tunnel support for Firefox. Using Firefox to start another instance of

Firefox during the first use of a smart tunnel requires the user profile named csco_st. If this user profile is not present, the session prompts the user to create one.

•

•

Applications using TCP that are dynamically linked to the SSL library can work over a smart tunnel.

Smart tunnel does not support the following on Mac OS:

–

–

Proxy services.

Auto sign-on.

–

–

Applications that use two-level name spaces.

Console-based applications, such as Telnet, SSH, and cURL.

–

–

Applications using dlopen or dlsym to locate libsocket calls.

Statically linked applications to locate libsocket calls.

Configuring a Smart Tunnel (Lotus example)

To configure a Smart Tunnel, perform the following steps:

Note

These example instructions provide the minimum instructions required to add smart tunnel support for an application. See the field descriptions in the sections that follow for more information.

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Step 1

Step 2

Step 3

Step 4

Step 5

Choose

Configuration > Remote Access VPN > Clientless SSL VPN Access > Portal > Smart

Tunnels

.

Double-click the smart tunnel list to which you want to add an application; or click

Add

to create a list of applications, enter a name for this list in the List Name field, and click

Add

.

For example, click

Add

in the Smart Tunnels pane, enter Lotus in the List Name field, and click

Add

.

Click

Add

in the Add or Edit Smart Tunnel List dialog box.

Enter a string in the Application ID field to serve as a unique index to the entry within the smart tunnel list.

Enter the filename and extension of the application into the Process Name dialog box.

Table 67-2

shows example Application ID strings and the associated paths required to support Lotus.

Table 67-2 Smart Tunnel Example: Lotus 6.0 Thick Client with Domino Server 6.5.5

Application ID Example

lotusnotes lotusnlnotes lotusntaskldr lotusnfileret

Minimum Required Process Name

notes.exe

nlnotes.exe

ntaskldr.exe

nfileret.exe

Step 6

Step 7

Step 8

Step 9

Step 10

Select

Windows

next to OS.

Click

OK

.

Repeat Steps

3

–

7 for each application to add to the list.

Click

OK

in the Add or Edit Smart Tunnel List dialog box.

Assign the list to the group policies and local user policies to which you want to provide smart tunnel access to the associated applications, as follows:

•

•

To assign the list to a group policy, choose

Configuration > Remote Access VPN> Clientless SSL

VPN Access > Group Policies > Add

or

Edit > Portal

and choose the smart tunnel name from the drop-down list next to the Smart Tunnel List attribute.

To assign the list to a local user policy, choose

Configuration > Remote Access VPN> AAA Setup

> Local Users > Add

or

Edit > VPN Policy > Clientless SSL VPN


Simplifying Configuration of Which Applications to Tunnel

A smart tunnel application list is essentially a filter of what applications are granted access to the tunnel.

The default is to allow access for all processes started by the browser. With Smart Tunnel enabled bookmark, the clientless session grants access only to processes initiated by the web browser. For non-browser applications, an administrator can choose to tunnel all applications and thus remove the

need to know which applications an end user may invoke. Table 67-3 shows in which situations

processes are granted access.

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Table 67-3 Access for Smart Tunnel Applications and Enabled Bookmarks

Application list specified

Smart tunnel is disabled

Smart Tunnel all

Applications check box is checked

Smart Tunnel Enabled Bookmark Smart Tunnel Application Access

Any processes that match a process name in the application list are granted access.

Only processes that match a process name in the application list are granted access.

All processes (and their child processes) are granted access.

All processes (and their child processes) are granted access.

Note

This includes processes initiated by non-Smart

Tunnel web pages if the web page is served by the same browser process.

No process is granted access.

All processes owned by the user who started the browser are granted access but not child processes of those original processes.

Note

This configuration is applicable to Windows platforms only.

Follow these steps to configure tunnel policy.

Step 1

Step 2

Step 3

Step 4

Step 5

Choose

Configuration > Remote Access VPN > AAA/Local Users > Local Users

.

In the User Account window, highlight the username that you want to edit.

Click

Edit

. The Edit User Account window appears.

In the left sidebar of the Edit User Account window, click

VPN Policy > Clientless SSL VPN

.

Perform one of the following:

•

Check the

smart tunnel_all_applications

check box. All applications will be tunneled without making a list or knowing which executables an end user may invoke for external applications.

•

Or choose from the following tunnel policy options:

–

–

Uncheck the

Inherit

check box at the Smart Tunnel Policy parameter.

Choose from the network list and specify one of the tunnel options: use smart tunnel for the specified network, do not use smart tunnel for the specified network, or use tunnel for all network traffic.

Add or Edit Smart Tunnel List

The Add Smart Tunnel List dialog box lets you add to the security appliance configuration a list of applications that can access smart tunnel. The Edit Smart Tunnel List dialog box lets you modify the contents of the list.

Field

•

List Name—Enter a unique name for the list of applications or programs. Do not use spaces.

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Following the configuration of the smart tunnel list, the list name appears next to the Smart Tunnel

List attribute in the Clientless SSL VPN group policies and local user policies. Assign a name that will help you to distinguish its contents or purpose from other lists that you are likely to configure.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Add or Edit Smart Tunnel Entry

The Add or Edit Smart Tunnel Entry dialog box lets you specify the attributes of an application in a smart tunnel list.

•

Application ID—Enter a string to name the entry in the smart tunnel list. This user-specified name is saved and then returned onto the GUI. The string is unique for the operating system. It typically names the application to be granted smart tunnel access. To support multiple versions of an application for which you choose to specify different paths or hash values, you can use this attribute to differentiate entries, specifying the operating system, and name and version of the application supported by each list entry. The string can be up to 64 characters.

•

Process Name

—

Enter the filename or path to the application. The string can be up to 128 characters.

Windows requires an exact match of this value to the right side of the application path on the remote host to qualify the application for smart tunnel access. If you specify only the filename for Windows,

SSL VPN does not enforce a location restriction on the remote host to qualify the application for smart tunnel access.

If you specify a path and the user installed the application in another location, that application does not qualify. The application can reside on any path as long as the right side of the string matches the value you enter.

To authorize an application for smart tunnel access if it is present on one of several paths on the remote host, either specify only the name and extension of the application in this field; or create a unique smart tunnel entry for each path.

Note

A sudden problem with smart tunnel access may be an indication that a

Process Name

value is not up-to-date with an application upgrade. For example, the default path to an application sometimes changes following the acquisition of the company that produces the application and the next application upgrade.

For Windows, if you want to add smart tunnel access to an application started from the command prompt, you must specify “cmd.exe” in the Process Name of one entry in the smart tunnel list, and specify the path to the application itself in another entry, because “cmd.exe” is the parent of the application.

Mac operating systems require the full path to the process and is case-sensitive. To avoid specifying a path for each username, insert a tilde (~) before the partial path (e.g., ~/bin/vnc).

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•

•

OS

—

Click

Windows

or

Mac

to specify the host operating system of the application.

Hash

—

(Optional and applicable only for Windows) To obtain this value, enter the checksum of the application (that is, the checksum of the executable file) into a utility that calculates a hash using the SHA-1 algorithm. One example of such a utility is the Microsoft File Checksum Integrity

Verifier (FCIV), which is available at http://support.microsoft.com/kb/841290/ . After installing

FCIV, place a temporary copy of the application to be hashed on a path that contains no spaces (for example, c:/fciv.exe), then enter

fciv.exe -sha1

application

at the command line (for example,

fciv.exe -sha1 c:\msimn.exe

) to display the SHA-1 hash.

The SHA-1 hash is always 40 hexadecimal characters.

Before authorizing an application for smart tunnel access, clientless SSL VPN calculates the hash of the application matching the

Application ID

. It qualifies the application for smart tunnel access if the result matches the value of

Hash

.

Entering a hash provides a reasonable assurance that SSL VPN does not qualify an illegitimate file that matches the string you specified in the

Application ID

. Because the checksum varies with each version or patch of an application, the

Hash

you enter can only match one version or patch on the remote host. To specify a hash for more than one version of an application, create a unique smart tunnel entry for each

Hash

value.

Note

You must update the smart tunnel list in the future if you enter

Hash

values and you want to support future versions or patches of an application with smart tunnel access. A sudden problem with smart tunnel access may be an indication that the application list containing

Hash

values is not up-to-date with an application upgrade. You can avoid this problem by not entering a hash.

Following the configuration of the smart tunnel list, you must assign it to a group policy or a local user policy for it to become active, as follows:

•


Config > Remote Access VPN> Clientless SSL VPN

Access > Group Policies > Add

or

Edit > Portal


•


Config > Remote Access VPN> AAA Setup > Local

Users > Add

or



Table 67-4 Example Smart Tunnel Entries

Application ID

(Any unique string is OK.) Smart Tunnel Support

Mozilla Firefox.

Microsoft Outlook Express.

More restrictive alternative—Microsoft

Outlook Express only if the executable file is in a predefined path.

firefox outlook-express outlook-express

Open a new Terminal window on a Mac. (Any subsequent application launched from within the same Terminal window fails because of the one-time-password implementation.) terminal

Process Name

firefox.exe

OS

Windows msimn.exe

Windows

\Program Files\Outlook Express\msimn.exe Windows

Terminal Mac

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Table 67-4 Example Smart Tunnel Entries

Smart Tunnel Support

Application ID

(Any unique string is OK.)

Start smart tunnel for a new window new-terminal

Start application from a Mac Terminal window. curl

Process Name

Terminal open -a MacTelnet

Terminal curl www.example.com

OS

Mac

Mac

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add or Edit Smart Tunnel Auto Sign-on Server List

The Add Smart Tunnel Auto Sign-on Server List dialog box lets you add one or more lists of servers for which to automate the submission of login credentials during smart tunnel setup. The Edit Smart Tunnel

Auto-signon Server List dialog box lets you modify the contents of these lists.

Field

•

List Name—Enter a unique name for the list of remote servers. The string can be up to 64 characters.

Do not use spaces.

Following the configuration of the smart tunnel auto sign-on list, the list name appears next to the

Auto Sign-on Server List attribute under Smart Tunnel in the clientless SSL VPN group policy and local user policy configurations. Assign a name that will help you to distinguish its contents or purpose from other lists that you are likely to configure.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Add or Edit Smart Tunnel Auto Sign-on Server Entry

The Add or Edit Smart Tunnel Entry dialog box lets you identify a server to be added to a smart tunnel auto sign-on list. You can identify it by its hostname, or IP address and subnet mask.

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Caution

Use the address format used in the source code of the web pages on the intranet. If you are configuring smart tunnel auto sign-on for browser access and some web pages use host names and others use IP addresses, or you do not know, specify both in different smart tunnel auto sign-on entries. Otherwise, if a link on a web page uses a different format than the one you specify, it fails when the user clicks it.

•

Host name—Enter a hostname or wildcard mask to auto-authenticate to. You can use the following wildcard characters:

–

–

* to match any number of characters or zero characters

? to match any single character

•

•

–

[] to match any single character in the range expressed inside the brackets

For example, enter *.example.com. Using this option protects the configuration from dynamic changes to IP addresses.

IP Address

—

Enter an IP address to auto-authenticate to.

Subnet Mask—Sub-network of hosts associated with the IP address.

•

•

Use Windows domain name with user name (Optional) —Click to add the Windows domain to the username if authentication requires it. If you do so, be sure to specify the domain name when assigning the smart tunnel list to one or more group policies or local user policies.

Following the configuration of the smart tunnel auto sign-on server list, you must assign it to a group policy or a local user policy for it to become active, as follows:

•


Config > Remote Access VPN > Clientless SSL VPN

Access > Group Policies > Add

or

Edit > Portal

, find the Smart Tunnel area, and choose the list name from the drop-down list next to the Auto Sign-on Server List attribute.


Config > Remote Access VPN> AAA Setup > Local

Users > Add

or


, find the Smart Tunnel area, and choose the list name from the drop-down list next to the Auto Sign-on Server List attribute.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Logging Off Smart Tunnel

This section describes how to ensure that the smart tunnel is properly logged off. Smart tunnel can be logged off when all browser windows have been closed, or you can right click the notification icon and confirm log out.

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Note

We strongly recommend the use of the logout button on the portal. This method pertains to clientless

SSL VPNs and logs off regardless of whether smart tunnel is used or not. The notification icon should be used only when using standalone applications without the browser.

Without Using Notification Icon

If you choose to not use the notification icon, the VPN session closes when the user quits the browser, and the end user is logged off after all browsers are closed. For example, if you started a smart tunnel from Internet Explorer, the smart tunnel is turned off when no iexplore.exe is running. Smart tunnel can determine that the VPN session has ended even if the user closed all browsers without logging out.

Note

In some cases, a lingering browser process is unintentional and is strictly a result of an error.

Also, when a Secure Desktop is used, the browser process can run in another desktop even if the user closed all browsers within the secure desktop. Therefore, smart tunnel declares all browser instances gone when no more visible windows exist in the current desktop.

Note

Portal logout still takes effect and is not impacted.

See the

Cisco Security Appliance Command Reference Guide

( http://www.cisco.com/en/US/products/ps6120/prod_command_reference_list.html

) for the CLI command that configures log out properties and controls whether the user is presented with a logout icon for logging out.

Using the Notification Icon

If you want the user to keep accessing the VPN, even after all browsers are closed, choose the notification icon for log off. The VPN session will not close, even when the user has quit the browser; therefore, if a user is accessing some non-browser application (such as vnc), the connectivity remains even after all browsers are closed, but logout can still occur using the notification icon. Smart Tunnel may not detect a log off event that happens outside of the browser (such as logging off with the console

CLI).

The clientless portal may take awhile to detect a log off and actually exit the portal, even though the user is logged off immediately. The icon remains until the next operation that is tunneled by Smart Tunnel

(such as when an application tries to create a new connection).

Note

This icon is an alternative way to log out of SSL VPN. It is not an indicator of VPN session status.

To enable the icon in the notification area, follow these steps:

Step 1

Step 2

Step 3

Choose

Configuration > Remote Access VPN > Clientless SSL VPN Access > Portal > Smart

Tunnels

.

Enable the

Click on smart-tunnel logoff icon in the system tray

radio button.

In the Smart Tunnel Networks portion of the window, check

Add

and enter both the IP address and hostname of the network which should include the icon.


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Customizing the Clientless SSL VPN User Experience

Note

If you right click the icon, a single menu item appears which prompts the user to log out of the

SSL VPN.


You can customize the clientless SSL VPN user experience, including the logon, portal, and logout pages. There are two methods you can use. You can customize pre-defined page components in the

Add/Edit Customization Object window. This window adds, or makes changes to, an XML file stored on the adaptive security appliance (a customization object) that is used to customize the pages.

Alternatively, you can export the XML file to a local computer or server, make changes to the XML tags, and re-import the file to the adaptive security appliance. Either method creates a customization object that you apply to a connection profile or group policy.

Rather than customizing the pre-defined components of the logon page, you can create your own page and import it to the adaptive security appliance for full customization. To do this see

Replacing the

Logon Page with your own Fully Customized Page, page 67-46

.

The following sections describe how to create a customization object:

•

•

•

Customizing the Logon Page, page 67-44

Customizing the Portal Page, page 67-49

Customizing the Logout Page, page 67-50

Customizing the Logon Page

You can customize pre-defined components of the logon page, including titles, language options, and messages to users. Alternatively, you can completely replace the page with your own custom page (full customization). The following sections detail both procedures:

•

•

Customizing the Logon Page with the Customization Editor, page 67-45

Replacing the Logon Page with your own Fully Customized Page, page 67-46

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Customizing the Logon Page with the Customization Editor

Figure 67-4 shows the logon page and the pre-defined components you can customize:

Figure 67-4 Components of Clientless Logon Page

Brow s er Window

Title

Inform a tion a l

P a nel

Title

P a nel

Logon Form a nd Field s Order

L a ng ua ge

OL-20339-01

Copyright P a nel

To customize all the components of the logon page, follow this procedure. You can preview your changes for each component by clicking the Preview button:

Step 1

Step 2

Step 3

Step 4

Specify pre-defined customization. Go to Logon Page and select

Customize pre-defined logon page components

. Specify a title for the browser window.

Display and customize the title panel. Go to Logon Page > Title Panel and check

Display title panel

.

Enter text to display as the title and specify a logo. Specify any font styles.

Specify language options to display. Go to Logon Page > Language and check

Enable Language

Selector

. Add or delete any languages to display to remote users. Languages in the list require translation tables that you configure in Configuration > Remote Access VPN > Language Localization.

Customize the logon form. Go to Logon Page > Logon Form. Customize the text of the form and the font style in the panel. The secondary password field appears to users only if a secondary authentication server is configured in the connection profile.


67-45



Step 5

Step 6

Step 7

Step 8

Arrange the position of the logon form fields. Go to Logon Page > Form Fields Order. Use the up and down arrow buttons to change the order that the fields are displayed.

Add messages to users. Go to Logon Page > Informational Panel and check

Display informational panel

. Add text to display in the panel, change the position of the panel relative to the logon form, and specify a logo to display in this panel.

Display a copyright statement. Go to Logon Page > Copyright Panel and check

Display copyright panel

. Add text to display for copyright purposes.

Click OK, then apply the changes to the customization object you edited.

Replacing the Logon Page with your own Fully Customized Page

If you prefer to use your own, custom login screen, rather than changing specific components of the logon page we provide, you can perform this advanced customization using the Full Customization feature.

With Full Customization, you provide the HTML for your own login screen, and you insert Cisco HTML code that calls functions on the adaptive security appliance that create the Login form and the Language

Selector drop-down list.

This document describes the modifications you need to make to your HTML code and the tasks required to configure the adaptive security appliance to use your code.

Figure 67-5

shows a simple example of a custom login screen enabled by the Full Customization feature.

Figure 67-5 Example of Full Customization of Logon Page

The following sections describe the tasks to customize the login screen:

•

Create the Custom Login Screen File

•

Import the File and Images

67-46


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•

Configure the Security Appliance to use the Custom Login Screen

Create the Custom Login Screen File

The following HTML code is used as an example and is the code that displays the screen shown in

Figure 67-5 :

<head>

<meta http-equiv="Content-Type" content="text/html; charset=windows-1252">

<title>New Page 3</title>

<base target="_self">

</head>

<p align="center">

<img border="0" src="/+CSCOU+/cisco_logo.jpg" width="188" height="48"><font face="Snap

ITC" size="6" color="#FF00FF">

</font><font face="Snap ITC" color="#FF00FF" size="7"> </font><i><b><font color="#FF0000" size="7" face="Sylfaen"> SSL VPN Service by the Cisco

ASA5500</font></b></i></p>

<body onload="csco_ShowLoginForm('lform');csco_ShowLanguageSelector('selector')">

<table>

<tr><td colspan=3 height=20 align=right><div id="selector" style="width:

300px"></div></td></tr>

<tr><td></td><td></td><td></td></tr>

<tr>

<td height="379"></td>


<td align=middle valign=middle>

<div id=lform >

<p> </p>

<p> </p>

<p> </p>

<p>Loading...</p>

</div>

</td>

</tr>

<tr>

<td width="251"></td>

<td width="1"></td>

<td align=right valign=right width="800">

<img border="1" src="/+CSCOU+/asa5500.jpg" width="660" height="220" align="middle">

</td></tr>

</table>

The indented code injects the Login form and the Language Selector on the screen. The function

csco_ShowLoginForm('lform')

injects the logon form.

csco_ShowLanguageSelector('selector')

injects the Language Selector.

Follow these steps to modify your HTML file:

Step 1

Step 2

Name your file

logon.inc

. When you import the file, the adaptive security appliance recognizes this filename as the logon screen.

Modify the paths of images used by the file to include

/+CSCOU+/

.

Files that are displayed to remote users before authentication must reside in a specific area of the adaptive security appliance cache memory represented by the path /+CSCOU+/. Therefore, the source for each image in the file must include this path. For example:


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Step 3 src=”/+CSCOU+/asa5520.gif”

Insert the special HTML code below. This code contains the Cisco functions, described earlier, that inject the login form and language selector onto the screen.

<body onload="csco_ShowLoginForm('lform');csco_ShowLanguageSelector('selector')">

<table>

<tr><td colspan=3 height=20 align=right><div id="selector" style="width:

300px"></div></td></tr>

<tr><td></td><td></td><td></td></tr>

<tr>



<td align=middle valign=middle>

<div id=lform >

<p> </p>

<p> </p>

<p> </p>

<p>Loading...</p>

</div>

</td>

</tr>

<tr>

<td width="251"></td>

<td width="1"></td>

<td align=right valign=right width="800">

<img border="1" src="/+CSCOU+/asa5500.jpg" width="660" height="220" align="middle">

</td></tr>

</table>

Import the File and Images

Follow these steps to import your HTML file and any images to the adaptive security appliance:

Step 1

Step 2

Import the file and images as Web Content.

Go to

Clientless SSL VPN Access > Portal > Web Contents

.

Click Import (1). The Import Web Content window displays. Enter the Source information (2). In the

Destination area, select

No

for

Require Authentication to access its content

(3). This ensures the files are stored in the area of flash memory accessible to users before authentication.

Import any images used by the file as Web Content using the same window.

Configure the Security Appliance to use the Custom Login Screen

Follow these steps to enable the adaptive security appliance to use the new login screen in a customization object:

Step 1

Step 2

Step 3

Step 4

Select a customization object. Go to

Clientless SSL VPN Access > Portal > Customization

. Select a customization object in the table and click

Edit

. The Edit Customization Object window displays.

In the navigation pane, select Logon Page.

Choose Replace pre-defined logon page with a custom page.

Click

Manage

to import your logon page file. The Import Web Content window displays.


67-48 OL-20339-01



Step 5

Step 6

In the Destination area, select

No

to ensure your logon page is visible to users before they authenticate.

Back in the Edit Customization Object window, click General and enable the customization object for the connection profile and/or group policies you desire.

Customizing the Portal Page

Figure 67-6 shows the portal page and the pre-defined components you can customize:

Figure 67-6 Customizable Components of the Portal Page

Title P a nel Tool B a r C us tom P a ne s

Home

P a ge

Applic a tion s

OL-20339-01

In addition to customizing the components of the page, you can divide the portal page into custom panes

that display text, an image, an RSS feed, or HTML. In Figure 67-6

, the portal page is divided into one column with two rows.

To customize the portal page, follow this procedure. You can preview your changes for each component by clicking the

Preview

button:

Step 1

Step 2

Step 3

Step 4

Go to Portal Page and specify a title for the browser window.

Display and customize the title panel. Go to Portal Page > Title Panel and check

Display title panel

.

Enter text to display as the title and specify a logo. Specify any font styles.

Enable and customize the toolbar. Go to Portal Page > Toolbar and check

Display toolbar

. Customize the Prompt Box, Browse button, and Logout prompt as desired.

Customize the Applications list. Go to Portal Page > Applications and check

Show navigation panel

.

The applications populated in the table are those applications you enabled in the adaptive security appliance configuration, including client-server plugins and port forwarding applications.


67-49



Step 5

Step 6

Create custom panes in the portal page space. Go to Portal Page > Custom Panes and divide the window into rows and columns for text, images, RSS feeds, or HTML pages, as desired.

Specify a home page URL. Go to Portal Page > Home Page and check

Enable custom intranet web page

. Choose a bookmark mode that defines how bookmarks are organized.

Customizing the Logout Page

Figure 67-7

shows the logout page you can customize:

Figure 67-7 Components of the Logout Page

Title a nd Text

To customize the logout page, follow this procedure. You can preview your changes for each component by clicking the

Preview

button:

Step 1

Step 2

Step 3

Step 4

Go to Logout Page. Customize the title or text as you desire.

For the convenience of the user, you can display the Login button on the Logout page. To do this, check

Show logon button

. Customize the button text, if desired.

Customize the title font or background, as desired.

Click OK, then apply the changes to the customization object you edited.

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Add Customization Object

To add a customization object, create a copy of and provide a unique name for the DfltCustomization object. Then you can modify or edit it to meet your requirements.

Field

Customization Object Name—Enter a name for the new customization object. Maximum 64 characters, no spaces.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Import/Export Customization Object

You can import or export already-existing customization objects. Import an object that you want to apply to end users. Export a customization object already resident on the adaptive security appliance for editing purposes, after which you can reimport it.

Fields

•

Customization Object Name—Identify the customization object by name. Maximum 64 characters, no spaces.

•

Select a file—Choose the method by which you want to import or export the customization file.

–

–

–

–

–

–

Local computer—Choose this method to import a file that resides on the local PC.

Path—Provide the path to the file.

Browse Local Files—Browse to the path for the file.

Flash file system—Choose this method to export a file that resides on the adaptive security appliance.


Browse Flash—Browse to the path for the file.

•

–

–

Remote server—Choose this option to import a customization file that resides on a remote server accessible from the adaptive security appliance.

Path—Identify the method to access the file (ftp, http, or https), and provide the path to the file.

Import/Export Now—Click to import or export the file.

Modes


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Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Creating XML-Based Portal Customization Objects and URL Lists


•

•

•

Understanding the XML Customization File Structure

Customization Example

Using the Customization Template

Understanding the XML Customization File Structure

Table 67-5 presents the file structure for an XML customization object.

Note

Absence of a parameter/tag results in a default/inherited value, while presence results in setting the parameter/tag value even it is an empty string.

Table 67-5

Tag custom

auth-page

window

title-text

title-panel

mode

text

logo-url

copyright-panel

mode

text

info-panel

mode

XML-Based Customization File Structure

Type Values node — node — node

string

node

text text text

node

text text

node

string

—

Arbitrary string

—

enable|disable

Arbitrary string

Arbitrary URL

—

enable|disable

Arbitrary URL

—

enable|disable

Preset value

—

—

—

Description

Tag-container of authentication page configuration

Browser window

empty string —

— The page top pane with a logo and a text

disable —

empty string —

empty image

URL

—

—

The page bottom pane with a copyright information

disable —

empty string —

— The pane with a custom text and image

disable —

67-52


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Table 67-5 XML-Based Customization File Structure (continued)

image-position string above|below

image-url

text

logon-form

string string

node

Arbitrary URL

Arbitrary string

—

Arbitrary string

Arbitrary string

Arbitrary string

above The image position, relative to text

empty image —

empty string —

— The form with username, password, group prompt

Logon —

empty string —

Username —

title-text

message-text username-prompt-text password-prompt-text internal-password-prompt

-text

group-prompt-text

submit-button-text

logout-form

string string string string string string string

node

Arbitrary string

Arbitrary string

Arbitrary string

Arbitrary string

—

Password

Internal

Password

—

—

title-text

message-text

login-button-text

close-button-text

language-selector

mode

title string string string string

node

string text

Arbitrary string

Arbitrary string

Arbitrary string

Arbitrary string

—

enable|disable

—

Group

Logon

—

—

Login

Close window

The form with a logout message and the buttons to login or close the window

Logout —

Empty string —

—

— The drop-down list to select a language

— disable

Language The prompt text to select language

language

portal

code

text

window

title-text

node

(multiple)

string string

node node

string

—

—

—

—

Arbitrary string

—

—

—

—

—

Tag-container of the portal page configuration

— see authentication page description

Empty string —

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67-53



Table 67-5

title-panel

mode

text

logo-url

mode

application

id

XML-Based Customization File Structure (continued)

node

navigation-panel

string string string

node

string

node

(multiple)

string

—

enable|disable

Arbitrary string

Arbitrary URL

—

enable|disable

—

For stock application web-access file-access app-access net-access help

—

Disable

see authentication page description

—

Empty string —

Empty image URL

—

—

enable

N/A

The pane on the left with application tabs

—

N/A

The node changes defaults for the configured (by id) application

—

tab-title

order string number

For ins:

Unique plug-in

—

—

N/A

N/A

url-list-title string

mode

toolbar

mode

prompt-box-title string

node

string string

browse-button-text string

— enable|disable

—

enable|disable

Arbitrary string

Arbitrary string

N/A

N/A

—

Enable

Address

Browse

—

Value used to sort elements. The default element order values have step 1000, 2000,

3000, etc. For example, to insert an element between the first and second element, use a value

1001 – 1999.

If the application has bookmarks, the title for the panel with grouped bookmarks v

—

—

Title for URL prompt list

Browse button text

67-54


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Table 67-5 XML-Based Customization File Structure (continued)

logout-prompt-text

column

width

order string

node

(multiple)

string number

Arbitrary string

—

—

—

Logout

—

N/A

N/A

url-lists

mode

panel

mode

title

type

url

url-mode

text

column

node

string node

(multiple) string

— enable|disable string string string string string number

—

group | nogroup

—

—

—

—

—

—


—

group

—

—

—

—

—

—

—

—

—

One column will be shown by default

—

Value used to sort elements.

URL lists are considered to be default elements on the portal home page, if they are not explicitly disabled

Modes: group – elements grouped by application type i.e.

Web Bookmarks, File

Bookmarks) no-group – url-lists are shown in separate panes disable – do not show

URL lists by default

Allows to configure extra panes

Used to temporarily disable the panel without removing its configuration

—

Supported types:

RSS

IMAGE

TEXT

HTML

URL for

RSS,IMAGE or

HTML type paned

Modes: mangle, no-mangle

Text for TEXT type panes

—

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Customization Example

The following example illustrates the following customization options:

•

Hides tab for the File access application

•

•

Changes title and order of Web Access application

Defines two columns on the home page

•

•

Adds an RSS pane

Adds three panes (text, image, and html) at the top of second pane

<custom name="Default">

<auth-page>

<window>

<title-text l10n="yes">title WebVPN Logon</title>

</window>

<title-panel>

<mode>enable</mode>

<text l10n="yes">EXAMPLE WebVPN</text>

<logo-url>http://www.example.com/images/EXAMPLE.gif</logo-url>

</title-panel>

<copyright>

<mode>enable</mode>

<text l10n="yes">(c)Copyright, EXAMPLE Inc., 2006</text>

</copyright>

<info-panel>

<mode>enable</mode>

<image-url>/+CSCOE+/custom/EXAMPLE.jpg</image-url>

<text l10n="yes">

<![CDATA[

<div>

<b>Welcome to WebVPN !.</b>

</div>

]]>

</text>

</info-panel>

<logon-form>

<form>


<message-text l10n="yes">message WebVPN Logon</title>

<username-prompt-text l10n="yes">Username</username-prompt-text>

<internal-password-prompt-text l10n="yes">Domain password</internal-password-prompt-text>

<group-prompt-text l10n="yes">Group</group-prompt-text>

<submit-button-text l10n="yes">Logon</submit-button-text>

</form>

</logon-form>

<logout-form>

<form>


<message-text l10n="yes">message WebVPN Logon</title>

<login-button-text l10n="yes">Login</login-button-text>

<close-button-text l10n="yes">Logon</close-button-text>

</form>

67-56


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</logout-form>

<language-slector>

<language>

<code l10n="yes">code1</code>

<text l10n="yes">text1</text>

</language>

<language>

<code l10n="yes">code2</code>

<text l10n="yes">text2</text>

</language>

</language-slector>

</auth-page>

<portal>

<window>


</window>

<title-panel>

<mode>enable</mode>

<text l10n="yes">EXAMPLE WebVPN</text>

<logo-url>http://www.example.com/logo.gif</logo-url>

</title-panel>

<navigation-panel>

<mode>enable</mode>

</navigation-panel>

<application>

<id>file-access</id>

<mode>disable</mode>

</application>

<application>

<id>web-access</id>

<tab-title>EXAMPLE Intranet</tab-title>

<order>3001</order>

</application>

<column>

<order>2</order>

<width>40%</width>

<column>

<column>

<order>1</order>

<width>60%</width>

<column>

<url-lists>

<mode>no-group</mode>

</url-lists>

<pane>

<id>rss_pane</id>

<type>RSS</type>

<url>rss.example.com?id=78</url>

</pane>

<pane>

<id>text_pane</id>

<type>TEXT</type>

<url>rss.example.com?id=78</url>


OL-20339-01 67-57



<column>1</column>

<row>0</row>

<text>Welcome to EXAMPLE WebVPN Service</text>

</pane>

<pane>

<type>IMAGE</type>

<url>http://www.example.com/logo.gif</url>

<column>1</column>

<row>2</row>

</pane>

<pane>

<type>HTML</type>

<title>EXAMPLE news</title>

<url>http://www.example.com/news.html</url>

<column>1</column>

<row>3</row>

</pane>

</portal>

</custom>

Using the Customization Template

A customization template, named

Template

, contains all currently employed tags with corresponding comments that describe how to use them. Use the

export

command to download the customization template from the adaptive security appliance, as follows: hostname# export webvpn customization Template tftp://webserver/default.xml

hostname#

You cannot change or delete the file

Template

. When you export it as in this example, you are saving it to a new name,

default.xml

. After you make your changes to this file, using it to create a customization object that meets the needs of your organization, you import it to the adaptive security appliance, either as

default.xml

or another name of your choosing. For example: hostname# import webvpn customization General tftp://webserver/custom.xml

hostname# where you import an XML object called

custom.xml

and name it

General

on the adaptive security appliance.

The Customization Template

The customization template, named

Template

, follows:

<?xml version="1.0" encoding="UTF-8" ?>



- <custom>

- <localization>

<languages>en,ja,zh,ru,ua</languages>

<default-language>en</default-language>

</localization>

- <auth-page>

- <window>

- <title-text l10n="yes">

- <![CDATA[

WebVPN Service

]]>

</title-text>

</window>

- <language-selector>


<title l10n="yes">Language:</title>

- <language>

<code>en</code>

<text>English</text>

</language>

- <language>

<code>zh</code>

<text>?? (Chinese)</text>

</language>

- <language>

<code>ja</code>

<text>?? (Japanese)</text>

</language>

- <language>

<code>ru</code>

<text>??????? (Russian)</text>


67-66 OL-20339-01



</language>

- <language>

<code>ua</code>

<text>?????????? (Ukrainian)</text>

</language>

</language-selector>

- <logon-form>


- <![CDATA[

Login

]]>

</title-text>

- <title-background-color>

- <![CDATA[

#666666

]]>

</title-background-color>

- <title-font-color>

- <![CDATA[

#ffffff

]]>

</title-font-color>

- <message-text l10n="yes">

- <![CDATA[

Please enter your username and password.

]]>

</message-text>

- <username-prompt-text l10n="yes">

- <![CDATA[

USERNAME:

]]>

</username-prompt-text>

- <password-prompt-text l10n="yes">

- <![CDATA[

PASSWORD:

]]>

</password-prompt-text>

<internal-password-prompt-text l10n="yes" />

<internal-password-first>no</internal-password-first>

- <group-prompt-text l10n="yes">

- <![CDATA[

GROUP:

]]>

</group-prompt-text>

- <submit-button-text l10n="yes">

- <![CDATA[

Login

]]>

</submit-button-text>

- <title-font-color>

- <![CDATA[

#ffffff

]]>

</title-font-color>

- <title-background-color>

- <![CDATA[

#666666

]]>

</title-background-color>

<font-color>#000000</font-color>

<background-color>#ffffff</background-color>

</logon-form>

- <logout-form>



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- <![CDATA[

Logout

]]>

</title-text>

- <message-text l10n="yes">

- <![CDATA[

Goodbye.

]]>

</message-text>

</logout-form>

- <title-panel>

<mode>enable</mode>

- <text l10n="yes">

- <![CDATA[

WebVPN Service

]]>

</text>

<logo-url l10n="yes">/+CSCOU+/csco_logo.gif</logo-url>

<gradient>yes</gradient>

<style />

- <background-color>

- <![CDATA[

#ffffff

]]>

</background-color>

- <font-size>

- <![CDATA[ larger

]]>

</font-size>

- <font-color>

- <![CDATA[

#800000

]]>

</font-color>

- <font-weight>

- <![CDATA[ bold

]]>

</font-weight>

</title-panel>

- <info-panel>


<image-url l10n="yes">/+CSCOU+/clear.gif</image-url>

<image-position>above</image-position>

<text l10n="yes" />

</info-panel>

- <copyright-panel>


<text l10n="yes" />

</copyright-panel>

</auth-page>

- <portal>

- <title-panel>

<mode>enable</mode>

- <text l10n="yes">

- <![CDATA[

WebVPN Service

]]>

</text>

<logo-url l10n="yes">/+CSCOU+/csco_logo.gif</logo-url>

<gradient>yes</gradient>

<style />

- <background-color>


67-68


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- <![CDATA[

#ffffff

]]>

</background-color>

- <font-size>

- <![CDATA[ larger

]]>

</font-size>

- <font-color>

- <![CDATA[

#800000

]]>

</font-color>

- <font-weight>

- <![CDATA[ bold

]]>

</font-weight>

</title-panel>

<browse-network-title l10n="yes">Browse Entire Network</browse-network-title>

<access-network-title l10n="yes">Start AnyConnect</access-network-title>

- <application>

<mode>enable</mode>

<id>home</id>

<tab-title l10n="yes">Home</tab-title>

<order>1</order>

</application>

- <application>

<mode>enable</mode>

<id>web-access</id>

- <tab-title l10n="yes">

- <![CDATA[

Web Applications

]]>

</tab-title>

- <url-list-title l10n="yes">

- <![CDATA[

Web Bookmarks

]]>

</url-list-title>

<order>2</order>

</application>

- <application>

<mode>enable</mode>

<id>file-access</id>


- <![CDATA[

Browse Networks

]]>

</tab-title>

- <url-list-title l10n="yes">

- <![CDATA[

File Folder Bookmarks

]]>

</url-list-title>

<order>3</order>

</application>

- <application>

<mode>enable</mode>

<id>app-access</id>


- <![CDATA[

Application Access


OL-20339-01 67-69


]]>

</tab-title>

<order>4</order>

</application>

- <application>

<mode>enable</mode>

<id>net-access</id>

<tab-title l10n="yes">AnyConnect</tab-title>

<order>4</order>

</application>

- <application>

<mode>enable</mode>

<id>help</id>

<tab-title l10n="yes">Help</tab-title>

<order>1000000</order>

</application>

- <toolbar>

<mode>enable</mode>

<logout-prompt-text l10n="yes">Logout</logout-prompt-text>

<prompt-box-title l10n="yes">Address</prompt-box-title>

<browse-button-text l10n="yes">Browse</browse-button-text>

</toolbar>

- <column>

<width>100%</width>

<order>1</order>

</column>

- <pane>

<type>TEXT</type>


<title />

<text />

<notitle />

<column />

<row />

<height />

</pane>

- <pane>

<type>IMAGE</type>


<title />

<url l10n="yes" />

<notitle />

<column />

<row />

<height />

</pane>

- <pane>

<type>HTML</type>


<title />

<url l10n="yes" />

<notitle />

<column />

<row />

<height />

</pane>

- <pane>

<type>RSS</type>


<title />

<url l10n="yes" />

<notitle />

<column />

<row />


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<height />

</pane>

- <url-lists>

<mode>group</mode>

</url-lists>

</portal>

</custom>

Help Customization

The adaptive security appliance displays help content on the application panes during clientless sessions.

Each clientless application pane displays its own help file content using a predetermined filename.

For example, the help content displayed on the Application Access panel is from the file named

app-access-hlp.inc. Table 67-6 shows the clientless application panels and predetermined filenames for

the help content.

Table 67-6 Clientless Applications

Application Type Panel

Standard Application Access

Standard

Standard

Browse Networks

AnyConnect Client

Standard

Plug-in

Plug-in

Plug-in

Plug-in

Web Access

MetaFrame Access

Terminal Servers

Telnet/SSH Servers

1

VNC Connections

1.

This plug-in is capable of doing both sshv1 and sshv2.

Filename

app-access-hlp.inc

file-access-hlp.inc

net-access-hlp.inc

web-access-hlp.inc

ica-hlp.inc

rdp-hlp.inc

ssh,telnet-hlp.inc

vnc-hlp.inc

You can customize the help files provided by Cisco or create help files in other languages. Then use the

Import button to copy them to the flash memory of the adaptive security appliance for display during subsequent clientless sessions. You can also export previously imported help content files, customize them, and reimport them to flash memory.

The following sections describe how to customize or create help content visible on clientless sessions:

•

•

Customizing a Help File Provided by Cisco

Creating Help Files for Languages Not Provided by Cisco

Fields

Import—Click to launch the Import Application Help Content dialog, where you can import new help content to flash memory for display during clientless sessions.

Export—Click to retrieve previously imported help content selected from the table.

Delete—Click to delete previously imported help content selected from the table.

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Language—Displays the abbreviation of the language rendered by the browser. This field is

not

used for file translation; it indicates the language used in the file. To identify the name of a language associated with an abbreviation in the table, display the list of languages rendered by your browser. For example, a dialog window displays the languages and associated language codes when you use one of the following procedures:

•

•

Open Internet Explorer and choose

Tools > Internet Options > Languages > Add

.

Open Mozilla Firefox and choose

Tools > Options > Advanced > General

, click

Choose

next to

Languages, and click

Select a language to add

.

Filename—Displays the filename the help content file was imported as.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Customizing a Help File Provided by Cisco

To customize a help file provided by Cisco, you need to get a copy of the file from the flash memory card first. Get the copy and customize it by performing the following steps:

Step 1

Step 2

Use your browser to establish a clientless session with the adaptive security appliance.

Display the help file by appending the string in “URL of Help File in Flash Memory of the Security

Appliance” in

Table 67-7

, to the address of the adaptive security appliance, substituting

language

as described below, then press

Enter

.

Table 67-7 Help Files Provided by Cisco for Clientless Applications

Application

Type

Standard

Standard

Standard

Standard

Plug-in

Plug-in

Plug-in

Panel

URL of Help File in Flash Memory of the Security

Appliance

Application Access /+CSCOE+/help/

language

/app-access-hlp.inc

Browse Networks /+CSCOE+/help/

language

/file-access-hlp.inc

AnyConnect Client /+CSCOE+/help/

language

/net-access-hlp.inc

Web Access

Terminal Servers

/+CSCOE+/help/

/+CSCOE+/help/

language language

/web-access-hlp.inc

/rdp-hlp.inc

Telnet/SSH Servers /+CSCOE+/help/

language

/ssh,telnet-hlp.inc

VNC Connections /+CSCOE+/help/

language

/vnc-hlp.inc

language

is the abbreviation for the language rendered by the browser. It is

not

used for file translation; it indicates the language used in the file. For help files provided by Cisco in English, enter the abbreviation

en

.

The following example address displays the English version of the Terminal Servers help:

https://

address_of_security_appliance

/+CSCOE+/help/en/rdp-hlp.inc

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Step 3

Choose

File > Save (Page) As

.

Caution

Do not change the contents of the File name box.

Step 4

Step 5

Change the Save as type option to “Web Page, HTML only” and click

Save

.

Use your preferred HTML editor to customize the file.

Note

You can use most HTML tags, but do

not

use tags that define the document and its structure (for example, do not use <html>, <title>, <body>, <head>, <h1>, <h2>, etc. You can use character tags, such as the <b> tag, and the <p>, <ol>, <ul>, and <li> tags to structure content.

Step 6

Step 7

Save the file as HTML only, using the original filename and extension.

Make sure the filename matches the one in

Table 67-7 , and that it does not have an extra filename

extension.

Return to ASDM and choose

Configuration > Remote Access VPN > Clientless SSL VPN Access

>

Portal

>


>

Import

to import the modified help file into flash memory.

Creating Help Files for Languages Not Provided by Cisco

Use standard HTML to create help files in other languages. We recommend creating a separate folder for each language you want to support.

Note

You can use most HTML tags, but do

not

use tags that define the document and its structure (for example, do not use <html>, <title>, <body>, <head>, <h1>, <h2>, etc. You can use character tags, such as the <b> tag, and the <p>, <ol>, <ul>, and <li> tags to structure content.

Save the file as HTML only. Use the filename in the Filename column of

Table 67-6

.

Return to ASDM and choose

Configuration > Remote Access VPN > Clientless SSL VPN Access

>

Portal

>


>

Import

to import the new help file into flash memory.

Import/Export Application Help Content

Use the Import Application Help Content dialog box to import help files to flash memory for display on the portal pages during clientless sessions. Use the Export Application Help Content dialog box to retrieve previously imported help files for subsequent editing.

Fields

Language—For the Import Application Help Content dialog box only, this field specifies the language rendered by the browser. (This Language field is inactive in the Export Application Help Content dialog box.) This field is not used for file translation; it indicates the language used in the file. Click the dots next to the Language field, double-click the row containing the language used in the help file in the

Browse Language Code dialog box, confirm the abbreviation in the Language Code field matches the abbreviation in the row, and click

OK

. If the language for which you want to provide help content is not present in the Browse Language Code dialog box, enter the abbreviation for the language you want into

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Configuring Browser Access to Client-Server Plug-ins

the Language Code field and click

OK

, or enter it into the Language text box to the left of the dots. To identify the abbreviation for the language of a help file to be imported if it is not present in the Browse

Language Code dialog box, display the list of languages and abbreviations rendered by your browser.

For example, a dialog box displays the languages and associated language codes when you use one of the following procedures:

•

•

Open Internet Explorer and choose

Tools > Internet Options > Languages > Add

.

Open Mozilla Firefox and choose

Tools > Options > Advanced > General

, click

Choose

next to

Languages, and click

Select a language to add

.

File Name—If you are importing, choose the filename from the drop-down list for the new help content file. If you are exporting, this field is unavailable.

Select a File—Configure the parameters for the source file (if importing) or destination file (if exporting):

Local computer—Indicate if the source or destination file is on a local computer:

–

Path—Identify the path of the source or destination file.

–

Browse Local Files—Click to browse the local computer for the source or destination file.

Flash file system—Indicate if the source or destination file is located in flash memory on the adaptive security appliance:

–

–

Path—Identify the path of the source or destination file in flash memory.

Browse Flash—Click to browse the flash memory for the source or destination file.

Remote server—Indicate if the source or destination file is on a remote server:

–

Path—Choose the file transfer (copy) method, either ftp, tftp, or http (for importing only), and specify the path.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—


The Client-Server Plug-in table displays the plug-ins the adaptive security appliance makes available to browsers in clientless SSL VPN sessions.

To add, change, or remove a plug-in, do one of the following:

•

To add a plug-in, click

Import

. The Import Plug-ins dialog box opens.

•

To remove a plug-in, choose it and click

Delete

.

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About Installing Browser Plug-ins

A browser plug-in is a separate program that a web browser invokes to perform a dedicated function, such as connect a client to a server within the browser window. The adaptive security appliance lets you import plug-ins for download to remote browsers in clientless SSL VPN sessions. Of course, Cisco tests the plug-ins it redistributes, and in some cases, tests the connectivity of plug-ins we cannot redistribute.

However, we do not recommend importing plug-ins that support streaming media at this time.

Note

Per the GNU General Public License (GPL), Cisco redistributes plug-ins without having made any changes to them. Per the GPL, Cisco cannot directly enhance these plug-ins.

The adaptive security appliance does the following when you install a plug-in onto the flash device:

•

(Cisco-distributed plug-ins only) Unpacks the jar file specified in the

URL

.

•

•

•

Writes the file to the csco-config/97/plugin directory on the adaptive security appliance file system.

Populates the drop-down menu next to the URL attributes in ASDM.

Enables the plug-in for all future clientless SSL VPN sessions, and adds a main menu option and an option to the drop-down menu next to the Address field of the portal page.

Table 67-8

shows the changes to the main menu and address field of the portal page when you add the plug-ins described in the following sections.

Table 67-8 Effects of Plug-ins on the Clientless SSL VPN Portal Page

Plug-in Main Menu Option Added to Portal Page

ica Citrix Client rdp rdp2

Terminal Servers

Terminal Servers Vista ssh,telnet SSH

Telnet vnc VNC Client

Address Field Option Added to Portal Page

citrix:// rdp:// rdp2:// ssh:// telnet:// vnc://

Note

A secondary adaptive security appliance obtains the plug-ins from the primary adaptive security appliance.

When the user in a clientless SSL VPN session clicks the associated menu option on the portal page, the portal page displays a window to the interface and displays a help pane. The user can select the protocol displayed in the drop-down menu and enter the URL in the Address field to establish a connection.

Note

Some Java plug-ins may report a status of connected or online even when a session to the destination service is not set up. The open-source plug-in reports the status, not the adaptive security appliance.

Before installing the first plug-in, you must follow the instructions in the next section.

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RDP Plug-in ActiveX Debug Quick Reference

To set up and use an RDP plug-in, you must add a new environment variable. For the process of adding a new environment variable, use the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Right click on My Computer to access the System Properties and choose the

Advanced

tab.

On the Advanced tab, choose the environment variables button.

In the new user variable dialog box, enter the RF_DEBUG variable.

Verify the new Environment Variable in the user variables section.

If you used the client computer with versions of WebVPN before version 8.3, you must remove the old

Cisco Portforwarder Control. Go to the C:/WINDOWS/Downloaded Program Files directory, right click on the portforwarder control, and choose

Remove

.

Clear all of the Internet Explorer browser cache.

Launch your WebVPN session and establish an RDP session with the RDP ActiveX Plug-in.

You can now observe events in the Windows Application Event viewer.

Plug-in Requirements and Restrictions

Clientless SSL VPN must be enabled on the adaptive security appliance to provide remote access to the plug-ins.

The plug-ins do not work if the security appliance configures the clientless session to use a proxy server.

Note

The remote desktop protocol plug-in does not support load balancing with a session broker.

Because of the way the protocol handles the redirect from the session broker, the connection fails. If a session broker is not used, the plug-in works.

The plug-ins support single sign-on (SSO). They use the

same

credentials entered to open the clientless

SSL VPN session. Because the plug-ins do not support macro substitution, you do not have the options to perform SSO on different fields such as the internal domain password or on an attribute on a Radius or LDAP server.

To configure SSO support for a plug-in, you install the plug-in, add a bookmark entry to display a link to the server, and specify SSO support when adding the bookmark.

The minimum access rights required for remote use belong to the guest privilege mode.

A stateful failover does not retain sessions established using plug-ins. Users must reconnect following a failover.

Plug-ins require ActiveX or Sun JRE 5, Update 1.4 or later (JRE 6 or later recommended) to be enabled on the browser. An ActiveX version of the RDP plug-in is unavailable for 64-bit browsers.

Preparing the Security Appliance for a Plug-in

Before installing a plug-in, prepare the adaptive security appliance by performing the following steps:

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Step 1

Step 2

Make sure clientless SSL VPN (“webvpn”) is enabled on a adaptive security appliance interface.

Install an SSL certificate onto the adaptive security appliance interface to which remote users use a fully-qualified domain name (FQDN) to connect.

Note

Do not specify an IP address as the common name (CN) for the SSL certificate. The remote user attempts to use the FQDN to communicate with the adaptive security appliance. The remote PC must be able to use DNS or an entry in the System32\drivers\etc\hosts file to resolve the FQDN.

See the section that identifies the type of plug-in you want to provide for clientless SSL VPN access.

•

Installing Plug-ins Redistributed by Cisco

•

Assembling and Installing Third-Party Plug-ins—Example: Citrix

Installing Plug-ins Redistributed by Cisco

Table 67-9

Cisco redistributes the following open-source, Java-based components to be accessed as plug-ins for web browsers in clientless SSL VPN sessions:

Plug-ins Redistributed by Cisco

Cisco Download Link Protocol Description

rdp-plugin.090915.jar

RDP Accesses Microsoft Terminal Services hosted by

Windows Vista and Windows 2003 R2.

Supports Remote Desktop ActiveX Control.

rdp2-plugin.090211.jar

rdp-plugin.080506.jar

RDP2

RDP

We recommend using this plug-in that supports both RDP and RDP2. Only versions up to 5.2 of the RDP and RDP2 protocols are supported.

Version 5.2 and later are not supported.

Accesses Microsoft Terminal Services hosted by

Windows Vista and Windows 2003 R2.


Note

This legacy plug-in supports only RDP2.

Accesses Microsoft Terminal Services hosted by

Windows 2003 R1.


Note

This legacy plug-in supports only RDP.

Source of Redistributed Plug-in

Cisco redistributes this plug-in without any changes to it per GNU

General Public License. The original source of the redistributed plug-in is http://properjavardp.sourceforge.net/

Cisco redistributes this plug-in without any changes to it per the

GNU General Public License. The original source of the redistributed plug-in is http://properjavardp.sourceforge.net/


GNU General Public License. The source of the redistributed plug-in is http://properjavardp.sourceforge.net/

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Table 67-9 Plug-ins Redistributed by Cisco

Cisco Download Link Protocol Description

ssh-plugin.080430.jar

SSH The Secure Shell-Telnet plug-in lets the remote user establish a Secure Shell or Telnet connection to a remote computer.

Note

Because keyboard-interactive authentication is not supported by

JavaSSH, it cannot be supported with SSH plugin. (Keyboard interactive is a generic authentication method used to implement different authentication mechanisms.

Source of Redistributed Plug-in


GNU General Public License. The web site containing the source of the redistributed plug-in is http://javassh.org/ vnc-plugin.080130.jar

VNC The Virtual Network Computing plug-in lets the remote user use a monitor, keyboard, and mouse to view and control a computer with remote desktop sharing turned on. This version changes the default color of the text, and contains updated

French and Japanese help files.


GNU General Public License. The web site containing the source of the redistributed plug-in is http://www.tightvnc.com/

To retrieve a plug-in redistributed by Cisco and import it into the adaptive security appliance, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Create a temporary directory named plugins on the computer you use to establish ASDM sessions with the adaptive security appliance.

Download the plug-ins you want from the Cisco website to the plugins directory.

Choose

Configuration

>


>


>

Portal

>

Client-Server

Plug-ins

.

This pane displays the plug-ins that are available to clientless SSL sessions. The hash and date of these plug-ins are also provided.

Click

Import

.

The Import Client-Server Plug-in dialog box opens.

Use the following descriptions to enter the field values.

Fields

The Import Client-Server Plug-in dialog box displays the following fields:

•

Plug-in Name—Select one of the following values:

–

– ica

to provide plug-in access to Citrix MetaFrame or Web Interface services. Then specify the path to the ica-plugin.jar file in the Remote Server field, as described below.

rdp

to provide plug-in access to Remote Desktop Protocol services. Then specify the path to the rdp-plugin.jar file in the Remote Server field.

–

– ssh,telnet

to provide plug-in access to

both

Secure Shell and Telnet services. Then specify the path to the ssh-plugin.jar file in the Remote Server field.

vnc

to provide plug-in access to Virtual Network Computing services. Then specify the path to the vnc-plugin.jar file in the Remote Server field.

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Step 6

Note

Any undocumented options in this menu are experimental and are not supported.

•

Select a file—Click one of the following options and insert a path into its text field.

–

Local computer—Click to retrieve the plug-in from the computer with which you have established the ASDM session. Enter the location and name of the plug-in into the associated

Path field, or click

Browse Local Files

and navigate to the plug-in, choose it, then click

Select

.

–

–

Flash file system—Click if the plug-in is present on the file system of the adaptive security appliance. Enter the location and name of the plug-in into the associated Path field, or click

Browse Flash


OK

.

Remote Server—Click to retrieve the plug-in from a host running an FTP or TFTP server.

Choose

ftp

,

tftp

, or

HTTP

from the drop-down menu next to the associated Path attribute, depending on which service is running on the remote server. Enter the host name or address of the server and the path to the plug-in into the adjacent text field.

Click

Import Now

.

Click

Apply

.

The plug-in is now available for future clientless SSL VPN sessions.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Assembling and Installing Third-Party Plug-ins—Example: Citrix

The open framework of the security appliance lets you add plug-ins to support third-party Java client/server applications. As an example of how to provide clientless SSL VPN browser access to third-party plug-ins, this section describes how to add clientless SSL VPN support for the Citrix

Presentation Server Client or Citrix Web Interface (for XenDesktop).

Caution

Cisco does not provide direct support for or recommend any particular plug-ins that are not redistributed by Cisco. As a provider of clientless SSL VPN services, you are responsible for reviewing and complying with any license agreements required for the use of plug-ins.

With a Citrix plug-in installed on the adaptive security appliance, clientless SSL VPN users can use a connection to the adaptive security appliance to access Citrix MetaFrame or Web Interface services.

A stateful failover does not retain sessions established using the Citrix plug-in. Citrix users must reauthenticate after failover.

To provide access to the Citrix plug-in, follow the procedures in the following sections.

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Preparing the Citrix MetraFrame Server for Clientless SSL VPN Access

The adaptive security appliance performs the connectivity functions of the Citrix secure gateway when the Citrix client connects to the Citrix MetaFrame Server or Web Interface. Therefore, you must configure the Citrix Web Interface software to operate in a mode that does not use the (Citrix) “secure gateway.” Otherwise, the Citrix client cannot connect to the Citrix MetaFrame Server.

Follow the instructions in the

“Preparing the Security Appliance for a Plug-in” section on page 67-78

before using the next section, if you are not already providing support for a plug-in.

Follow Steps 1 – 4 of http://support.citrix.com/article/CTX117597 if you are configuring access to Web

Interface (for XenDesktop), or you later upgrade to it, to avoid Cookies Required errors.

Creating, Installing, and Testing the Citrix Plug-in

To create and install the Citrix plug-in, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Download the ica-plugin.zip

file from the Cisco Software Download website .

This file contains files that Cisco customized for use with the Citrix plug-in.

Download the Citrix Java client from the Citrix site.

Extract the following files from the Citrix Java client:

•

JICA-configN.jar

•

JICAEngN.jar

You can use WinZip to perform this step and the next.

Add the extracted files to the ica-plugin.zip file.

Ensure the EULA included with the Citrix Java client grants you the rights and permissions to deploy the client on your web servers.

Establish an ASDM session with the adaptive security appliance, choose

Config

>


>


>

Portal

>

Client-Server Plug-ins

>

Import

, and import the ica-plugin.zip file.

Step 7

Step 8

Note

Users of clientless SSL VPN sessions cannot enter a URL in the Address box to get SSO support for Citrix sessions. You must insert a bookmark as instructed in the following step if you want to provide SSO support for the Citrix plug-in.

Add a bookmark to the applicable bookmark list to make it easy for users to connect. Choose

ica

and enter the following information into the Address field:

citrix-server

/?DesiredColor=4&DesiredHRes=1024&DesiredVRes=768

See

Add/Edit Bookmark List and

Add Bookmark Entry as needed.

To test the plug-in, establish a clientless session with the adaptive security appliance and click the bookmark.

Use the Client for Java Administrator’s Guide as needed.

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POST Plug-ins for Homepage SSO and Application-only Portals

The POST plug-in was developed to solve some key single sign-on (SSO) and homepage requirements for certain key applications like Citrix Web Interface. This clientless SSL VPN plug-in has the following key capabilities:

•

The option to display the homepage for a Web application (such as Citrix) in the right frame, as part of the default clientless portal, or as the only frame in the page (completely hiding anything that is part of the Cisco portal).

•

•

The option for SSO on the homepage or with an application using WebVPN variables (also known as macros) (and therefore HTTP-POST parameters).

The option to preload a page before issuing a POST request. This option becomes necessary when a logon page for an application sets some cookies.

POST plug-in has the following capabilities and restrictions:

•

It is strictly an HTML/JavaScript code and not a JAVA plug-in. It contains no client components.

•

•

No support on Firefox. It is supported only on Internet Explorer and Mac Safari.

Does not support URLs with queries such as http://example.company.com/names?Login. The ? character is not supported.

•

A POST plug-in adds approximately a 10-second delay to make sure an intermediate page is fully loaded with all objects for an application. This delay is beneficial for an application such as Citrix where an intermediate page performs client detection functions.

Configuring POST Plug-ins

Obtain the plug-in (such as post-plugin.080414.jar) from Plugins (Latest) at post-plugin.zip or from http://www.cisco.com/cgi-bin/tablebuild.pl/asa . Use the following procedures to configure the POST plug-in.

Step 1

Step 2

Step 3

Step 4

Step 5

Choose

Configuration > Remote Access VPN > Clientless SSL VPN Access > Portal > Client-Server

Plug-ins

.

Click

Import

.

The Import Client-Server Plug-in dialog box opens.

Choose

post

from the Plug-in Name (Protocol) drop-down menu.

Click one of the following options and insert a path into its text field.

•

•

Local computer—Click to retrieve the plug-in from the computer with which you have established the ASDM session. Enter the location and name of the plug-in into the associated Path field, or click


and navigate to the plug-in, choose it, and then click

Select

.

Flash file system—Click if the plug-in is present on the file system of the security appliance. Enter the location and name of the plug-in into the associated Path field, or click

Browse Flash


OK

.

•

Remote Server—Click to retrieve the plug-in from a host running an FTP or TFTP server. Choose

ftp

,

tftp

, or

HTTP

from the drop-down menu next to the associated Path attribute, depending on which service is running on the remote server. Enter the host name or address of the server and the path to the plug-in into the adjacent text field.

Click

Import Now

.

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Language Localization

Step 6

Click

Apply

.

The POST plug-in is now available for clientless SSL VPN sessions.


Configuring and Applying the POST URL

POST plug-ins are configured with the customization object. For example, to make a Citrix portal as the hompage after Clientless SSL VPN login, follow these steps:

Step 1

Add the POST URL of the Citrix server to the customization object in the Custom Intranet Web Page

URL field (see Figure 67-8

).

The Citrix server URL is http://mycitrix-server.abcd.com/Citrix/AccessPlatform/auth/login.aspx

Adding POST URL it becomes the following: post://mycitrix-server.abcd.com/Citrix/AccessPlatform/auth/login.aspx?LoginType=Explicit&user=CS

CO_WEBVPN_USERNAME&password=CSCO_WEBVPN_PASSWORD&csco_preload=http://mycit rix-server.abcd.com&csco_ispopup=yes.

Figure 67-8 SSL VPN Customization Editor Window

Step 2

Apply the customization object to the group or user.

For additional information on configuring SSO and the required parameters, refer to the SSL VPN deployment guide

(http://www.cisco.com/en/US/docs/security/asa/asa80/asdm60/ssl_vpn_deployment_guide/deploy.html

#wp1002989).


The adaptive security appliance provides language translation for the portal and screens displayed to users that initiate browser-based, clientless SSL VPN connections, screens associated with optional plug-ins, and the interface displayed to Cisco AnyConnect VPN Client users.

This section describes how to configure the adaptive security appliance to translate these user messages and includes the following sections:

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•

•

•

•

Understanding Language Translation, page 67-85

Creating a Translation Table, page 67-86

Add/Edit Localization Entry, page 67-87

Import/Export Language Localization, page 67-96

Understanding Language Translation

Each functional area and its messages that are visible to remote users are organized into translation domains.

Table 67-10 shows the translation domains and the functional areas translated.

Table 67-10 Translation Domains and Functional Areas Affected

Translation Domain Functional Areas Translated

AnyConnect

Messages displayed on the user interface of the Cisco AnyConnect VPN Client.

CSD customization keepout

PortForwarder

Messages for the Cisco Secure Desktop (CSD).

Messages on the logon and logout pages, portal page, and all the messages customizable by the user.

Message displayed to remote users when VPN access is denied.

Messages displayed to Port Forwarding users.

Text that user specifies for URL bookmarks on the portal page.

url-list webvpn plugin-ica

All the layer 7, AAA and portal messages that are not customizable.

Messages for the Citrix plug-in.

plugin-rdp plugin-telnet,ssh plugin-vnc

Messages for the Remote Desktop Protocol plug-in.

Messages for the Telnet and SSH plug-in.

Messages for the VNC plug-in.

The software image package for the adaptive security appliance includes a language localization template for each domain that is part of the standard functionality. The templates for plug-ins are included with the plug-ins and define their own translation domains.

You can export the template for a translation domain, which creates an XML file of the template at the

URL you provide. The message fields are empty in this file. You can customize the messages and import the template to create a new language localization table that resides in flash memory.

You can also export an existing language localization table. The XML file created displays the messages you edited previously. Reimporting this XML file with the same language name creates a new version of the language localization table, overwriting previous messages.

Some templates are static, but some change based on the configuration of the adaptive security appliance. Because you can customize the logon and logout pages, portal page, and URL bookmarks for clientless sessions, the adaptive security appliance generates the customization and url-list translation domain templates dynamically and the template automatically reflects your changes to these functional areas.

After creating language localization tables, they are available to customization objects that you create and apply to group policies or user attributes. A language localization table has no affect and messages are not translated on user screens until you create the customization object, identify a language localization table to use in that object, and specify the customization for the group policy or user.

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Fields

Add—Launches the Add Localization Entry dialog where you can select a localization template to add and you can edit the contents of the template.

Edit—Launches the Edit Localization Entry dialog for the selected language in the table, and allows you to edit the previously-imported language localization table.

Delete—Deletes a selected language localization table.

Import—Launches the Import Language Localization dialog where you can import a language localization template or table.

Export—Launches the Export Language Localization dialog where you can export a language localization template or table to a URL where you can make changes to the table or template.

Language—The language of existing Language Localization tables.

Language Localization Template—The template that the table is based on.

Creating a Translation Table

To create a translation table, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Choose

Remove Access VPN > Clientless SSL VPN Access > Portal > Advanced > Language

Localization

. The Language Localization pane displays. Click

Add

. The Add Language Localization window displays.

Choose a Language Localization Template from the drop-down box. The entries in the box correspond to functional areas that are translated. For more information about the functionality for each template, see table

Table 67-9

.

Specify a language for the template. The template becomes a translation table in cache memory with the name you specify. Use an abbreviation that is compatible with the language options for your browser.

For example, if you are creating a table for the Chinese language, and you are using IE, use the abbreviation

zh,

that is recognized by IE.

Edit the translation table. For each message represented by the msgid field that you want to translate, enter the translated text between the quotes of the associated msgstr field. The example below shows the message Connected, with the Spanish text in the msgstr field: msgid "Connected" msgstr "Conectado"

Click

OK

. The new table appears in the list of translation tables.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

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Add/Edit Localization Entry

You can add a new translation table, based on a template, or you can modify an already-imported translation table in this pane.

Fields

Language Localization Template—Select a template to modify and use as a basis for a new translation table. The templates are organized into translation domains and affect certain areas of functionality. The following table shows the translation domains and the functional areas affected:

Translation Domain Functional Areas Translated

AnyConnect

Messages displayed on the user interface of the Cisco AnyConnect VPN client.

CSD customization

Messages for the Cisco Secure Desktop (CSD).

Messages on the logon and logout pages, portal page, and all the messages customizable by the user.

keepout

PortForwarder url-list webvpn plugin-ica plugin-rdp plugin-telnet,ssh plugin-vnc

Message displayed to remote users when VPN access is denied.

Messages displayed to Port Forwarding users.

Text that user specifies for URL bookmarks on the portal page.

All the layer 7, AAA and portal messages that are not customizable.

Messages for the Citrix plug-in.

Messages for the Remote Desktop Protocol plug-in.

Messages for the Telnet and SSH plug-in.

Messages for the VNC plug-in.

Language—Specify a language. Use an abbreviation that is compatible with the language options of your browser. The adaptive security appliance creates the new translation table with this name.

Text Editor—Use the editor to change the message translations. The message ID field (msgid) contains the default translation. The message string field (msgstr) that follows msgid provides the translation. To create a translation, enter the translated text between the quotes of the msgstr string. For example, to translate the message “Connected” with a Spanish translation, insert the Spanish text between the msgstr quotes: msgid "Connected" msgstr "Conectado"

After making changes, click

Apply

to import the translation table.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

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Customizing the AnyConnect Client


You can customize the AnyConnect VPN client to display your own corporate image to remote users, including clients running on Windows, Linux, and Mac OS X computers.

Note

Customization is not supported for the AnyConnect client running on a Windows Mobile device.

You can use one of three methods to customize the client:

–

Rebrand the client by importing individual client GUI components, such as the corporate logo and icons, to the adaptive security appliance which deploys them to remote computers with the installer.

–

–

Import your own program (Windows and Linux only) that provides its own GUI or CLI and uses the AnyConnect API.

Import a transform (Windows only) that you create for more extensive rebranding. The adaptive security appliance deploys it with installer.

–

Create Scripts that deploy with the client and run when the client establishes or terminates a

VPN connection.

The following sections explain how to customize the AnyConnect client:

•

Customizing AnyConnect by Importing Resource Files, page 67-88

•

•

•

•

Customizing AnyConnect with you own GUI and Scripts, page 67-89

Customizing AnyConnect GUI Text and Messages, page 67-93

Customizing the Installer Program using Installer Transforms, page 67-94

Localizing the Install Program using Installer Transforms, page 67-95

Customizing AnyConnect by Importing Resource Files

You can customize the AnyConnect client by importing your own custom files to the security appliance, which deploys the new files with the client. For detailed information about about the original GUI icons and information about their sizes, see the

AnyConnect VPN Client Administrators Guide

. You can use this information to create your custom files.

To import and deploy your custom files with the client, follow this procedure:

Step 1

Step 2

Go to

Configuration > Remote Access VPN > Network (Client) Access > AnyConnect

Customization/Localization > Resources

.

Click

Import

. The Import AnyConnect Customization Object window displays.

Enter the Name of the file to import. See the


for the filenames of all the GUI components that you can replace.

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Step 3

Note

The filenames of your custom components must match the filenames used by the AnyConnect client GUI. The filenames of the GUI components are different for each OS and are case sensitive for Mac and Linux. For example, if you want to replace the corporate logo for Windows clients, you must import your corporate logo as

company_logo.bmp

. If you import it as a different filename, the AnyConnect installer does not change the component. However, if you deploy your own executable to customize the GUI, the executable can call resource files using any filename.

Select a platform and specify the file to import. Click

Import Now

. The file now appears in the table.

Note

If you import an image as a resource file (such as company_logo.bmp), the image you import customizes the AnyConnect client until you reimport another image using the same filename. For example, if you replace company_logo.bmp with a custom image, and then delete the image, the client continues to display your image until you import a new image (or the original Cisco logo image) using the same filename.

Fields

Import—Launches the Import AnyConnect Customization Objects dialog, where you can specify a file to import as an object.

Export—Launches the Export AnyConnect Customization Objects dialog, where you can specify a file to export as an object.

Delete—Removes the selected object.

Platform—The type of remote PC platform supported by the object.

Object Name—The name of the object.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Customizing AnyConnect with you own GUI and Scripts

For Windows, Linux, or Mac (PPP or Intel-based) computers, you can deploy your own client that uses the AnyConnect client API. You replace the AnyConnect GUI or the AnyConnect CLI by replacing the client binary files.

You can also download and run scripts that run when the client establishes a connection (an

OnConnect

script), or when the client terminates a session (an

OnDisconnect

script). Some examples that show how you might want to use this feature include:

•

•

Refreshing the group policy upon VPN connection.

Mapping a network drive upon VPN connection, and un-mapping it after disconnection.

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•

Logging on to a service upon VPN connection, and logging off after disconnection.

For complete information about customizing the AnyConnect GUI and creating and deploying scripts, see the


.

The following sections describe how to import binary executables and scripts to the adaptive security appliance:

Importing your own GUI as a Binary Executable, page 67-90

Importing Scripts, page 67-91

Importing your own GUI as a Binary Executable

For Windows, Linux, or Mac (PPP or Intel-based) computers, you can deploy your own client that uses the AnyConnect client API. You replace the AnyConnect GUI or the AnyConnect CLI by replacing the client binary files.

Table 67-11 lists the filenames of the client executable files for the different operating

systems.

Table 67-11 Filenames of Client Executables

Client OS

Windows

Linux

Mac

Client GUI File

vpnui.exe

vpnui

Not supported

1

Client CLI File

vpncli.exe

vpn vpn

1.

Not supported by adaptive security appliance deployment. However, you can deploy an executable for the Mac that replaces the client GUI using other means, such as

Altiris Agent.

Your executable can call any resource files, such as logo images, that you import to the adaptive security appliance (See

Table 67-11 ). Unlike replacing the pre-defined GUI components, when you deploy your

own executable, can use any filenames for your resource files.

We recommend that you sign your custom Windows client binaries (either GUI or CLI version) that you import to the adaptive security appliance. A signed binary has a wider range of functionality available to it. If the binaries are not signed the following functionality is affected:

•

•

Web-Launch—The clientless portal is available and the user can authenticate. However, the behavior surrounding tunnel establishment does not work as expected. Having an unsigned GUI on the client results in the client not starting as part of the clientless connection attempt. And once it detects this condition, it aborts the connection attempt.

SBL—The Start Before Logon feature requires that the client GUI used to prompt for user credentials be signed. If it is not, the GUI does not start. Because SBL is not supported for the CLI program, this affects only the GUI binary file.

•

Auto Upgrade—During the upgrade to a newer version of the client, the old GUI exits, and after the new GUI installs, the new GUI starts. The new GUI does not start unless it is signed. As with

Web-launch, the VPN connection terminates if the GUI is not signed. However, the upgraded client remains installed.

Note

The adaptive security appliance does not support this feature for the AnyConnect VPN client, Versions

2.0 and 2.1. For more information on manually customizing the client, see the

AnyConnect VPN Client

Administrator Guide

and the

Release Notes for Cisco AnyConnect VPN Client

.

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Importing Scripts

AnyConnect lets you download and run scripts when the following events occur:

•

Upon the establishment of a new AnyConnect client VPN session with the security appliance. We refer to a script triggered by this event as an

OnConnect

script because it requires this filename prefix.

•

Upon the tear-down of an AnyConnect client VPN session with the security appliance. We refer to a script triggered by this event as an

OnDisconnect

script because it requires this filename prefix.

Thus, the establishment of a new AnyConnect VPN session initiated by Trusted Network Detection triggers the OnConnect script (assuming the requirements are satisfied to run the script). The reconnection of a persistent AnyConnect VPN session after a network disruption does not trigger the

OnConnect script.

These instructions assume you know how to write scripts and run them from the command line of the targeted endpoint to test them.

Note

The AnyConnect software download site provides some example scripts; if you examine them, please remember that they are only examples; they may not satisfy the local computer requirements for running them, and are unlikely to be usable without customizing them for your network and user needs. Cisco does not support example scripts or customer-written scripts.

For complete information about deploying scripts, and their limitations and restrictions, see the


.

Writing, Testing, and Deploying Scripts

Deploy AnyConnect scripts as follows:

Step 1

Write and test the script using the OS type on which it will run when AnyConnect launches it.

Note

Scripts written on Microsoft Windows computers have different line endings than scripts written on Mac OS and Linux. Therefore, you should write and test the script on the targeted OS. If a script cannot run properly from the command line on the native OS, AnyConnect cannot run it properly either.

Step 2

To import a script, go to

Network (Client) Access > AnyConnect Customization/Localization >

Script.

The Customization Scripts pane displays.

Note

Microsoft Windows Mobile does not support this option. You must deploy scripts using the manual method for this OS.

Step 3

Step 4

Enter a name for the script. Be sure to specify the correct extention with the name. For example,

myscript

.bat.

Choose a script action:

Script runs when client connects

or

Script runs when client disconnects

.

AnyConnect adds the prefix

scripts_

and the prefix

OnConnect

or

OnDisconnect

to your filename to identify the file as a script on the adaptive security appliance. When the client connects, the adaptive security appliance downloads the script to the proper target directory on the remote computer, removing the

scripts_

prefix and leaving the remaining

OnConnect

or

OnDisconnect

prefix. For example, if you

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Table 67-12

Step 5

import the script

myscript.bat

, the script appears on the adaptive security appliance as

scripts_OnConnect_myscript.bat

. On the remote computer, the script appears as

OnConnect_myscript.bat.

To ensure the scripts run reliably, configure all adaptive security appliances to deploy the same scripts.

If you want to modify or replace a script, use the same name as the previous version and assign the replacement script to all of the adaptive security appliances that the users might connect to. When the user connects, the new script overwrites the one with the same name.

Select a file as the source of the script. The name does not need to be the same as the name you provided for the script. ASDM imports the file from any source file, creating the new name you specify for Name in Step 3.

Table 67-12

shows the locations of scripts on the remote computer:

Required Script Locations

OS Directory

Microsoft Windows 7 and Vista %ALLUSERPROFILE%\Cisco\Cisco AnyConnect VPN Client\Scripts

Microsoft Windows XP

Linux

%ALLUSERPROFILE%\Application Data\Cisco\Cisco AnyConnect VPN Client\

Scripts

/opt/cisco/vpn/scripts

Mac OS X

Windows Mobile

Note

Assign execute permissions to the file for User, Group and Other.

/opt/cisco/vpn/scripts

%PROGRAMFILES%\Cisco AnyConnect VPN Client\Scripts

Fields

Import—Launches the Import AnyConnect Customization Objects dialog, where you can specify a file to import as an object.

Export—Launches the Export AnyConnect Customization Objects dialog, where you can specify a file to export as an object.

Delete—Removes the selected object.

Platform—The type of remote PC platform supported by the object.

Object Name—The name of the object.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

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Customizing AnyConnect GUI Text and Messages

Change text and messages displayed on the AnyConnect client GUI displayed to remote users in this pane. This pane also shares functionality with the Language Localization pane. For more extensive language translation, go to Configuration > Remote Access VPN > Language Localization.

To change messages that appear on the AnyConnect GUI, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Click

Template

to expand the template area. Click

Export

to export the English language template to your local PC or a remote device.

Edit the template and make changes to any messages. The text contained between the quotes of the msgid field represents the default text.

Do not

change this text. To display a different message, insert your custom text between the quotes of mgstr. The example below shows a message containing connection termination information: msgid ""

"The VPN connection has been disconnected due to the system suspending. The

"reconnect capability is disabled. A new connection requires re-"

"authentication and must be started manually. Close all sensitive networked

"applications." msgstr ""

Click

Import

to import the file you edited as a new translation template.

Specify a language for the template. The template becomes a translation table in cache memory with the name you specify. Use an abbreviation that is compatible with the language options for your browser.

For example, if you are creating a table for the Chinese language, and you are using IE, use the abbreviation

zh,

that is recognized by IE.

Click

Apply to make your changes to the

adaptive security appliance.

Fields

Add

—Launches the Add Localization Entry dialog where you can select a localization template to add and you can edit the contents of the template.

Edit

—Launches the Edit Localization Entry dialog for the selected language in the table, and allows you to edit the previously-imported language localization table.

Delete

—Deletes a selected language localization table.

Import

—Launches the Import Language Localization dialog where you can import a language localization template or table.

Export

—Launches the Export Language Localization dialog where you can export a language localization template or table to a URL where you can make changes to the table or template.

Language

—The language of existing Language Localization tables.

Template—Expands the Template area:

•

•

View—Displays the contents of the English language template.

Export—Launches the Export Language Localization dialog where you can export the English language template to a URL where you can make changes.

Modes


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Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Customizing the Installer Program using Installer Transforms

You can perform more extensive customizing of the AnyConnect client GUI (Windows only) by creating your own transform that deploys with the client installer program. You import the transform to the adaptive security appliance, which deploys it with the installer program.

To create an MSI transform, you can download and install the free database editor from Microsoft, named Orca. With this tool, you can modify existing installations and even add new files. The Orca tool is part of the Microsoft Windows Installer Software Development Kit (SDK) which is included in the

Microsoft Windows SDK. The following link leads to the bundle containing the Orca program: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/orca_exe.asp.

After you install the SDK, the Orca MSI is located here:

C:\Program Files\Microsoft SDK SP1\Microsoft Platform SDK\Bin\Orca.msi.

Install the Orca software, then access the Orca program from your Start > All Programs menu.

To import your transform, follow these steps:

Step 1

Step 2

Step 3

Go to

Configuration > Remote Access VPN > Network (Client) Access > AnyConnect

Customization/Localization > Customized Installer Transforms

. Click

Import

.

The Import

AnyConnect Customization Objects windows displays.

Enter the Name of the file to import. Unlike the names of other customizing objects, the name is not significant to the adaptive security appliance and is for your own convenience.

Select a platform and specify the file to import. Click

Import Now

. The file now appears in the table.

Note

Windows is the only valid choice for applying a transform.

Sample Transform

While offering a tutorial on creating transforms is beyond the scope of this document, we provide the text below as representative of some entries in a transform. These entries replace

company_logo.bmp

with a local copy and install the custom profile

MyProfile.xml

.

DATA CHANGE - Component Component ComponentId

+ MyProfile.xml {39057042-16A2-4034-87C0-8330104D8180}

Directory_ Attributes Condition KeyPath

Profile_DIR 0 MyProfile.xml

DATA CHANGE - FeatureComponents Feature_ Component_

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+ MainFeature MyProfile.xml

DATA CHANGE - File File Component_ FileName FileSize Version Language Attributes Sequence

+ MyProfile.xml MyProfile.xml MyProf~1.xml|MyProfile.xml 601 8192 35

<> company_logo.bmp 37302{39430} 8192{0}

DATA CHANGE - Media DiskId LastSequence DiskPrompt Cabinet VolumeLabel Source

+ 2 35

Specify transform files for customizing the AnyConnect client installation in this pane.

Fields

Import—Launches the Import AnyConnect Customization Objects dialog, where you can specify a transform file to import.

Export—Launches the Export AnyConnect Customization Objects dialog, where you can specify a transform file to export.

Delete—Removes the selected file.

Platform—The type of remote PC platform supported by the transform.

Object Name—The name of the transform.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Localizing the Install Program using Installer Transforms

As with the AnyConnect client GUI, you can translate messages displayed by the client installer program. The adaptive security appliance uses transforms to translate the messages displayed by the installer. The transform alters the installation, but leaves the original security-signed MSI intact. These transforms only translate the installer screens and do not translate the client GUI screens.

Each language has its own transform. You can edit a transform with a transform editor such as Orca, and make changes to the message strings. Then you import the transform to the adaptive security appliance.

When the user downloads the client, the client detects the preferred language of the computer (the locale specified during installation of the operating system) and applies the appropriate transform.

We currently offer transforms for 30 languages. These transforms are available in the following .zip file on the AnyConnect client software download page at cisco.com: anyconnect-win-<VERSION>-web-deploy-k9-lang.zip

In this file,

<VERSION>

is the version of AnyConnect release (e.g. 2.2.103).

The package contains the transforms (.mst files) for the available translations. If you need to provide a language to remote users that is not one of the 30 languages we provide, you can create your own transform and import it to the adaptive security appliance as a new language. With Orca, the database

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editor from Microsoft, you can modify existing installations and new files. Orca is part of the Microsoft

Windows Installer Software Development Kit (SDK) which is included in the Microsoft Windows SDK.

The following link leads to the bundle containing the Orca program: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/msi/setup/orca_exe.asp.

After you install the SDK, the Orca MSI is located here:

C:\Program Files\Microsoft SDK SP1\Microsoft Platform SDK\Bin\Orca.msi.

The following procedure shows how to import a transform to the adaptive security appliance using

ASDM:

Step 1

Step 2

Step 3

Import a Transform. Go to:

Configuration > Remote Access VPN > Network (Client) Access >

AnyConnect Customization/Localization > Localized Installer Transforms

. Click

Import

. The

Import MST Language Localization window opens.

Choose a language for this transform. Click the Language drop-list to display languages and their industry-recognized abbreviations. If you enter the abbreviation manually, be sure to use an abbreviation recognized by browsers and operating systems.

Click

Import Now

. A message displays saying you successfully imported the table.

Be sure to click

Apply


Fields

Import—Launches the Import AnyConnect Customization Objects dialog, where you can specify a file to import as an transform.

Export—Launches the Export AnyConnect Customization Objects dialog, where you can specify a file to export as an transform.

Delete—Removes the selected transform.

Platform—The type of remote PC platform supported by the transform.

Object Name—The name of the transform.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Import/Export Language Localization

In the Import Translation Table and Export Translation Table dialog boxes you can import or export a translation table to the adaptive security appliance to provide translation of user messages.

Translation templates are XML files that contain message fields that can be edited with translated messages. You can export a template, edit the message fields, and import the template as a new translation table, or you can export an existing translation table, edit the message fields, and re-import the table to overwrite the previous version.

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Fields

•

Language—Enter a name for the language.

When

exporting

, it is automatically filled-in with the name from the entry you selected in the table.

•

When

importing

, you enter the language name in the manner that you want it to be identified. The imported translation table then appears in the list with the abbreviation you designated. To ensure that your browser recognizes the language, use language abbreviations that are compatible with the language options of the browser. For example, if you are using IE, use

zh

as the abbreviation for the

Chinese language.

Localization Template Name—The name of the XML file containing the message fields. The following templates are available:

–

–

–

–

AnyConnect—Messages displayed on the user interface of the Cisco AnyConnect VPN Client.

CSD—Messages for the Cisco Secure Desktop (CSD).

customization—Messages on the logon and logout pages, portal page, and all the messages customizable by the user.

keepout—Message displayed to remote users when VPN access is denied.

–

–

–

–

–

–

PortForwarder—Messages displayed to Port Forwarding users.

url-list—Text that user specifies for URL bookmarks on the portal page.

webvpn—All the layer 7, AAA and portal messages that are not customizable.

plugin-ica—Messages for the Citrix plug-in.

plugin-rdp—Messages for the Remote Desktop Protocol plug-in.

plugin-telnet,ssh—Messages for the TELNET and SSH plug-in. This plug-in is capable of doing both sshv1 and sshv2.

•

•

–

plugin-vnc—Messages for the VNC plug-in.

Select a file—Choose the method by which you want to import or export the file.

–

–

Remote server—Select this option to import a customization file that resides on a remote server accessible from the adaptive security appliance.


–

–

Flash file system—Choose this method to export a file that resides on the adaptive security appliance.


–

–

–

–

Browse Flash—Browse to the path for the file.

Local computer—Choose this method to import a file that resides on the local PC.


Browse Local Files—Browse to the path for the file.


Modes


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Configuring Bookmarks

Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—


The Bookmarks panel lets you add, edit, delete, import, and export bookmark lists.

Use the Bookmarks panel to configure lists of servers and URLs for access over clientless SSL VPN.

Following the configuration of a bookmark list, you can assign the list to one or more policies – group policies, dynamic access policies, or both. Each policy can have only one bookmark list. The list names populate a drop-down list on the URL Lists tab of each DAP.

Caution

Configuring bookmarks does not prevent the user from visiting fraudulent sites or sites that violate your company's acceptable use policy. In addition to assigning a bookmark list to the group policy, dynamic access policy, or both, apply a web ACL to these policies to control access to traffic flows. Disable URL

Entry on these policies to prevent user confusion over what is accessible. See

Security Precautions, page 67-1 for instructions.

Fields

•

Bookmarks—Displays the existing bookmark lists.

•

Add—Click to add a new bookmark list.

•

•

•

•

Edit—Click to edit the selected bookmark list.

Delete—Click to delete the selected bookmark list.

Import—Click to import a bookmark list.

Export—Click to export a bookmark list.

Modes


Firewall Mode

Routed

•


•


Multiple

•

Context

—

System

—

Add/Edit Bookmark List

The Add/Edit Bookmark List dialog box configure lists of servers and URLs for access over lets you add, edit, or delete a URL list, and also order the items in a designated URL list.

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Fields

•

Bookmark List Name—Specifies the name of the list to be added or selects the name of the list to be modified or deleted.

•

Bookmark Title—Specifies the URL name displayed to the user.

•

•

•

•

•


Add—Opens the Add Bookmark Entry dialog box, on which you can configure a new server or URL and display name.

Edit—Opens the Edit Bookmark Entry dialog box, on which you can configure a new server or URL and display name.

Delete—Removes the selected item from the URL list. There is no confirmation or undo.

Move Up/Move Down—Changes the position of the selected item in the URL list.

Modes


Firewall Mode

Routed

•


•


Multiple

•

Context

—

System

—

Add Bookmark Entry

The Add Bookmark Entry dialog box lets you create a link or bookmark for a URL list.

Fields

•

Bookmark Title—Enter a name for the bookmark to display for the user.

•

URL (drop-down)—Use the drop-down menu to select the URL type: http, https, cifs, or ftp. The

URL types of all imported plug-ins also populate this menu. Select the URL type of a plug-in if you want to display the plug-in as a link on the portal page.

•

URL (text box)—Enter the DNS name or IP address for the bookmark. For a plug-in, enter the name of the server. Enter a forward slash and a question mark (/?) after the server name to specify optional parameters, then use an ampersand to separate parameter-value pairs, as shown in the following syntax:

server

/?

Parameter

=

Value

&

Parameter

=

Value

For example:

host

/?DesiredColor=4&DesiredHRes=1024&DesiredVRes=768

The particular plug-in determines the optional parameter-value pairs that you can enter.

To provide single sign-on support for a plug-in, use the parameter-value pair

csco_sso=1

. For example:

host

/?csco_sso=1&DesiredColor=4&DesiredHRes=1024&DesiredVRes=768

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Note

To access \\server\share\subfolder\<

personal folder

>, the user must have list permission for all points above <

personal folder

>.

•

•

•

•

•

•

Subtitle—Provide additional user-visible text that describes the bookmark entry.

Thumbnail—Use the drop-down menu to select an icon to associate with the bookmark on the end-user portal.

Manage—Click to import or export images to use as thumbnails.

Enable Smart Tunnel Option—Click to open the bookmark in a new window that uses the smart tunnel feature to pass data through the adaptive security appliance to or from the destination server.

All browser traffic passes securely over the SSL VPN tunnel. This option lets you provide smart tunnel support for a browser-based application, whereas the Smart Tunnels option, also in the

Clientless SSL VPN > Portal menu, lets you add nonbrowser-based applications to a smart tunnel list for assignment to group policies and usernames.

Allow the users to bookmark the link—Check to let clientless SSL VPN users use the Bookmarks or Favorites options on their browsers. Uncheck to prevent access to these options. If you uncheck this option, the bookmark does not appear in the Home section of the WebVPN portal.

Advanced Options—(Optional) Open to configure further bookmark characteristics.

–

URL Method—Choose

Get

for simple data retrieval. Choose

Post

when processing the data might involve changes to it, for example, storing or updating data, ordering a product, or sending e-mail.

–

Post Parameters—Configure the particulars of the Post URL method.

–

–

Add/Edit—Click to add a post parameter.

Edit—Click to edit the highlighted post parameter.

–

Delete—Click to delete the highlighted post parameter.

Modes


Firewall Mode

Routed

•


•


Multiple

•

Context

—

System

—

Import/Export Bookmark List

You can import or export already configured bookmark lists. Import lists that are ready to use. Export lists to modify or edit them, and then reimport.

Fields

•

Bookmark List Name—Identify the list by name. Maximum 64 characters, no spaces.

•

Select a file—Choose the method by which you want to import or export the list file.

–

Local computer—Click to import a file that resides on the local PC.

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•

–

–

–

Flash file system—Click to export a file that resides on the adaptive security appliance.

Remote server—Click to import a url list file that resides on a remote server accessible from the adaptive security appliance.


–

Browse Local Files/Browse Flash—Browse to the path for the file.

Import/Export Now—Click to import or export the list file.

Modes


Firewall Mode

Routed



Multiple

Context

• • •

—

System

—

Configure GUI Customization Objects (Web Contents)

This dialogue box lets you import and export web content objects.

Fields

•

File Name—Displays the names of the web content objects.

•

•

•

File Type—Identifies the file type(s).

Import/Export—Click to import or export a web content object.

Delete—Click to delete the object.

Import/Export Web Content

Web contents can range from a wholly configured home page to icons or images you want to use when you customize the end user portal. You can import or export already configured web contents. Import web contents that are ready for use. Export web contents to modify or edit them, and then reimport.

Fields

•

Source—Choose the location from which you want to import or export the file.

–

–

Local computer—Click to import or export a file that resides on the local PC.

Flash file system—Click to import or export a file that resides on the adaptive security appliance.

•

–

–

Remote server—Click to import a file that resides on a remote server accessible from the adaptive security appliance.


–

Browse Local Files.../Browse Flash...—Browse to the path for the file.

Destination

–

Require authentication to access its content? Click

Yes

or

No

.

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•

–

WebContent Path: Notice that the prefix to the path changes depending on whether you require authentication. The adaptive security appliance uses /+CSCOE+/ for objects that require authentication, and /+CSCOU+/ for objects that do not. The adaptive security appliance displays /+CSCOE+/ objects on the portal page only, while /+CSCOU+/ objects are visible and usable in either the logon or the portal pages.


Modes


Firewall Mode

Routed

•


•


Multiple

•

Context

—

System

—

Add/Edit Post Parameter

Use this pane to configure post parameters for bookmark entries and URL lists.

About Clientless SSL VPN Variable Substitutions

Clientless SSL VPN variables allow for substitutions in URLs and forms-based HTTP post operations.

These variables, also known as macros, let you configure users for access to personalized resources that contain the user ID and password or other input parameters. Examples of such resources include bookmark entries, URL lists, and file shares.

No. Variable Substitution

1 CSCO_WEBVPN_USERNAME

2 CSCO_WEBVPN_PASSWORD

3 CSCO_WEBVPN_INTERNAL_PASSWORD

4

Fields

•

Name, Value—Provide the name and value of the parameters exactly as in the corresponding HTML form, for example: <input name=“

param_name

” value=“

param_value

”>.

You can choose one of the supplied variables from the drop-down list, or you can construct a variable. The variables you can choose from the drop-down list include the following:

Table 67-13 Clientless SSL VPN Variables

CSCO_WEBVPN_CONNECTION_PROFILE

Definition

SSL VPN user login ID

SSL VPN user login password

SSL VPN user internal resource password. This is a cached credential, and not authenticated by a AAA server. If a user enters this value, it is used as the password for auto-signon, instead of the password value.

SSL VPN user login group drop-down, a group alias within the connection profile

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Table 67-13 Clientless SSL VPN Variables

No. Variable Substitution

5 CSCO_WEBVPN_MACRO1

Definition

Set via RADIUS/LDAP vendor-specific attribute. I f you are mapping this from LDAP via an ldap-attribute-map, the Cisco attribute that uses this variable is

WEBVPN-Macro-Substitution-Value1.

6 CSCO_WEBVPN_MACRO2

Variable substitution via RADIUS is performed by VSA#223.

Set via RADIUS/LDAP vendor-specific attribute. If you are mapping this from LDAP via an ldap-attribute-map, the Cisco attribute that uses this variable is WEBVPN-Macro-Substitution-Value2.

7 CSCO_WEBVPN_PRIMARY_USERNAME

Variable substitution via RADIUS is performed by VSA#224.

Primary user login ID for double authentication.

8 CSCO_WEBVPN_PRIMARY_PASSWORD Primary user login password for double authentication.

9 CSCO_WEBVPN_SECONDARY_USERNAME Secondary user login ID for double authentication.

10 CSCO_WEBVPN_SECONDARY_PASSWORD Secondary user login ID for double authentication.

When the adaptive security appliance recognizes one of these six variable strings in an end-user request—in a bookmark or a post form—it replaces it with the user-specific value before passing the request to a remote server.

Note

You can obtain the http-post parameters for any application by performing an HTTP Sniffer trace in the clear (without the security appliance involved). Here is a link to a free browser capture tool, also called an HTTP Analyzer: http://www.ieinspector.com/httpanalyzer/downloadV2/IEHttpAnalyzerV2.exe

.

Using Variables 1 - 4

The adaptive security appliance obtains values for the first four substitutions from the SSL VPN Login page, which includes fields for username, password, internal password (optional), and group. It recognizes these strings in user requests, and replaces them with the value specific to the user before it passes the request on to a remote server.

For example, if a URL list contains the link, http://someserver/homepage/CSCO_WEBVPN_USERNAME.html

, the adaptive security appliance translates it to the following unique links:

•

•

For USER1 the link becomes http://someserver/homepage/USER1.htm

l

•

For USER2 the link is http://someserver/homepage/USER2.html

In the following case, cifs://server/users/CSCO_WEBVPN_USERNAME, lets the adaptive security appliance map a file drive to specific users:

•

For USER1 the link becomes cifs://server/users/USER1

For USER1 the link is cifs://server/users/USER2

Using Variables 5 and 6

Values for macros 5 and 6 are RADIUS or LDAP vendor-specific attributes (VSAs). These substitutions let you set substitutions configured on either a RADIUS or an LDAP server.

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Using Variables 7 - 10

Each time the adaptive security appliance recognizes one of these four strings in an end-user request (a bookmark or a post form), it replaces it with the user-specific value before passing the request to a remote server.

Example 1: Setting a Homepage

The following example sets a URL for the homepage:

•

WebVPN-Macro-Value1 (ID=223), type string, is returned as

wwwin-portal.example.com

•

WebVPN-Macro-Value2 (ID=224), type string, is returned as

401k.com

To set a home page value, you would configure the variable substitution as https://CSCO_WEBVPN_MACRO1, which would translate to https://wwwin-portal.example.com.

The best way to do this is to configure the Homepage URL parameter in ASDM.

Go to the Add/Edit Group Policy pane, from either the Network Client SSL VPN or Clientless SSL VPN

Access section of ASDM, as in Figure 67-9Using ASDM to Configure a Macro that Sets a Homepage .

The paths are as follows:

•

Configuration > Remote Access VPN > Network (Client) Access > Group Policies > Add/Edit

Group Policy > Advanced > SSL VPN Client > Customization > Homepage URL attribute.

•

Configuration > Remote Access VPN > Clientless SSL VPN Access > Group Policies > Add/Edit

Group Policy > More Options > Customization > Homepage URL attribute.

Figure 67-9 Using ASDM to Configure a Macro that Sets a Homepage

Example 2: Setting a Bookmark or URL Entry

You can use an HTTP Post to log in to an OWA resource using an RSA one-time password (OTP) for

SSL VPN authentication, and then the static, internal password for OWA e-mail access. The best way to do this is to add or edit a bookmark entry in ASDM (

Figure 67-10 ).

There are several paths to the Add Bookmark Entry pane, including the following:

•

Configuration > Remote Access VPN > Clientless SSL VPN Access > Portal > Bookmarks >

Add/Edit Bookmark Lists > Add/Edit Bookmark Entry > Advanced Options area > Add/Edit Post

Parameters (available after you click

Post

in the URL Method attribute).

or

(Available after you click

Post

in the URL Method attribute):

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•

Network (Client) Access > Dynamic Access Policies > Add/Edit Dynamic Access Policy > URL

Lists tab > Manage button > Configured GUI Customization Objects > Add/Edit button > Add/Edit

Bookmark List > Add/Edit Bookmark Entry > Advanced Options area > Add/Edit Post Parameters.

Figure 67-10 Configuring a Bookmark Entry

Example 3: Configuring File Share (CIFS) URL Substitutions

You can allow a more flexible bookmark configuration by using variable substitution for CIFS URLs.

If you configure the URL cifs://server/CSCO_WEBVPN_USERNAME, the adaptive security appliance automatically maps it to the user’s file share home directory. This method also allows for password and internal password substitution. The following are example URL substitutions: cifs://CSCO_WEBVPN_USERNAME:CSCO_WEBVPN_PASSWORD@server cifs://CSCO_WEBVPN_USERNAME:CSCO_WEBVPN_INTERNAL_PASSWORD@server cifs://domain;CSCO_WEBVPN_USERNAME:CSCO_WEBVPN_PASSWORD@server cifs://domain;CSCO_WEBVPN_USERNAME:CSCO_WEBVPN_INTERNAL_PASSWORD@server cifs://domain;CSCO_WEBVPN_USERNAME:CSCO_WEBVPN_PASSWORD@server/CSCO_WEB

VPN_USERNAME cifs://domain;CSCO_WEBVPN_USERNAME:CSCO_WEBVPN_INTERNAL_PASSWORD@server/

CSCO_WEBVPN_USERNAME

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More examples

For more variable substitution examples, see the

Cisco ASA 5500 SSL VPN Deployment Guide

on cisco.com.

Modes


Firewall Mode

Routed

•


Multiple


• •

Context

—

System

—

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C H A P T E R

68

E-Mail Proxy

E-mail proxies extend remote e-mail capability to users of Clientless SSL VPN. When users attempt an e-mail session via e-mail proxy, the e-mail client establishes a tunnel using the SSL protocol.

The e-mail proxy protocols are as follows:

POP3S

POP3S is one of the e-mail proxies Clientless SSL VPN supports. By default the Security Appliance listens to port 995, and connections are automatically allowed to port 995 or to the configured port. The

POP3 proxy allows only SSL connections on that port. After the SSL tunnel establishes, the POP3 protocol starts, and then authentication occurs. POP3S is for receiving e-mail.

IMAP4S

IMAP4S is one of the e-mail proxies Clientless SSL VPN supports. By default the Security Appliance listens to port 993, and connections are automatically allowed to port 993 or to the configured port. The

IMAP4 proxy allows only SSL connections on that port. After the SSL tunnel establishes, the IMAP4 protocol starts, and then authentication occurs. IMAP4S is for receiving e-mail.

SMTPS

SMTPS is one of the e-mail proxies Clientless SSL VPN supports. By default, the Security Appliance listens to port 988, and connections automatically are allowed to port 988 or to the configured port. The

SMTPS proxy allows only SSL connections on that port. After the SSL tunnel establishes, the SMTPS protocol starts, and then authentication occurs. SMTPS is for sending e-mail.

Configuring E-Mail Proxy

Configuring e-mail proxy on the consists of the following tasks:

•

Enabling e-Mail proxy on interfaces.

•

Configuring e-mail proxy default servers.

•

•

Setting AAA server groups and a default group policy.

Configuring delimiters.

Configuring E-mail proxy also has these requirements:

•

•

Users who access e-mail from both local and remote locations via e-mail proxy require separate e-mail accounts on their e-mail program for local and remote access.

E-mail proxy sessions require that the user authenticate.

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AAA

AAA

Chapter 68 E-Mail Proxy

This panel has three tabs:

•

POP3S Tab

•

•

IMAP4S Tab

SMTPS Tab

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

POP3S Tab

The POP3S AAA panel associates AAA server groups and configures the default group policy for

POP3S sessions.

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AAA

Fields

•

AAA server groups—Click to go to the AAA Server Groups panel (Configuration > Features >

Properties > AAA Setup > AAA Server Groups), where you can add or edit AAA server groups.

•

group policies—Click to go to the Group Policy panel (Configuration > Features > VPN >

General > Group Policy), where you can add or edit group policies.

•

•

•

•

Authentication Server Group—Select the authentication server group for POP3S user authentication. The default is to have no authentication servers configured. If you have set AAA as the authentication method for POP3S (Configuration > Features AAA > VPN > E-Mail Proxy >

Authentication panel), you must configure an AAA server and select it here, or authentication always fails.

Authorization Server Group—Select the authorization server group for POP3S user authorization.

The default is to have no authorization servers configured.

Accounting Server Group—Select the accounting server group for POP3S user accounting. The default is to have no accounting servers configured.

Default Group Policy—Select the group policy to apply to POP3S users when AAA does not return a CLASSID attribute. The length must be between 4 and 15 alphanumeric characters. If you do not specify a default group policy, and there is no CLASSID, the adaptive security appliance can not establish the session.

•

Authorization Settings—Lets you set values for usernames that the adaptive security appliance recognizes for POP3S authorization. This applies to POP3S users that authenticate with digital certificates and require LDAP or RADIUS authorization.

–

User the entire DN as the username—Select to use the Distinguished Name for POP3S authorization.

–

Specify individual DN fields as the username—Select to specify specific DN fields for user authorization.

You can choose two DN fields, primary and secondary. For example, if you choose EA, users authenticate according to their e-mail address. Then a user with the Common Name (CN) John

Doe and an e-mail address of [email protected] cannot authenticate as John Doe or as johndoe. He must authenticate as [email protected]. If you choose EA and O, John Does must authenticate as [email protected] and Cisco Systems, Inc.

–

Primary DN Field—Select the primary DN field you want to configure for POP3S authorization.

The default is CN. Options include the following:

DN Field

Country (C)

Common Name (CN)

DN Qualifier (DNQ)

E-mail Address (EA)

Generational Qualifier

(GENQ)

Given Name (GN)

Initials (I)

Locality (L)

Definition









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68-3

AAA


DN Field

Name (N)

Organization (O)

Organizational Unit

(OU)

Serial Number (SER)

Surname (SN)

State/Province (S/P)

Title (T)

User ID (UID)

Definition









–

Secondary DN Field—(Optional) Select the secondary DN field you want to configure for

POP3S authorization. The default is OU. Options include all of those in the preceding table, with the addition of

None

, which you select if you do not want to include a secondary field.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

IMAP4S Tab

The IMAP4S AAA panel associates AAA server groups and configures the default group policy for

IMAP4S sessions.

Fields

•



•

group policy—Click to go to the Group Policy panel (Configuration > Features > VPN > General

> Group Policy), where you can add or edit group policies.

•

•

•

Authentication Server Group—Select the authentication server group for IMAP4S user authentication. The default is to have no authentication servers configured. If you have set AAA as the authentication method for IMAP4S (Configuration > Features AAA > VPN > E-Mail Proxy

> Authentication panel), you must configure an AAA server and select it here, or authentication always fails.

Authorization Server Group—Select the authorization server group for IMAP4S user authorization.


Accounting Server Group—Select the accounting server group for IMAP4S user accounting. The default is to have no accounting servers configured.

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AAA

•

•

Default Group Policy—Select the group policy to apply to IMAP4S users when AAA does not return a CLASSID attribute. If you do not specify a default group policy, and there is no CLASSID, the adaptive security appliance can not establish the session.

Authorization Settings—Lets you set values for usernames that the adaptive security appliance recognizes for IMAP4S authorization. This applies to IMAP4S users that authenticate with digital certificates and require LDAP or RADIUS authorization.

–

User the entire DN as the username—Select to use the fully qualified domain name for IMAP4S authorization.

–



Doe and an e-mail address of [email protected] cannot authenticate as John Doe or as johndoe. He must authenticate as [email protected]. If you choose EA and O, John Does must authenticate as [email protected]

and

Cisco. Systems, Inc.

– Primary DN Field

—Select the primary DN field you want to configure for IMAP4S authorization. The default is CN. Options include the following:

DN Field

Country (C)

Common Name (CN)

DN Qualifier (DNQ)

E-mail Address (EA)


(GENQ)

Given Name (GN)

Initials (I)

Locality (L)

Name (N)

Organization (O)

Organizational Unit

(OU)

Serial Number (SER)

Surname (SN)


Title (T)

User ID (UID)

Definition

















–

Secondary DN Field—(Optional) Select the secondary DN field you want to configure for

IMAP4S authorization. The default is OU. Options include all of those in the preceding table, with the addition of None, which you select if you do not want to include a secondary field.

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AAA

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

SMTPS Tab

The SMTPS AAA panel associates AAA server groups and configures the default group policy for

SMTPS sessions.

Fields

•



•

group policy—Click to go to the Group Policy panel (Configuration > Features > VPN > General

> Group Policy), where you can add or edit group policies.

•

•

•

•

Authentication Server Group—Select the authentication server group for SMTPS user authentication. The default is to have no authentication servers configured. If you have set AAA as the authentication method for SMTPS (Configuration > Features AAA > VPN > E-Mail Proxy >

Authentication panel), you must configure an AAA server and select it here, or authentication always fails.

Authorization Server Group—Select the authorization server group for SMTPS user authorization.


Accounting Server Group—Select the accounting server group for SMTPS user accounting. The default is to have no accounting servers configured.

Default Group Policy—Select the group policy to apply to SMTPS users when AAA does not return a CLASSID attribute. If you do not specify a default group policy, and there is no CLASSID, the adaptive security appliance can not establish the session.

•

Authorization Settings—Lets you set values for usernames that the adaptive security appliance recognizes for SMTPS authorization. This applies to SMTPS users that authenticate with digital certificates and require LDAP or RADIUS authorization.

–

User the entire DN as the username—Select to use the fully qualified domain name for SMTPS authorization.

–



Doe and an e-mail address of [email protected] cannot authenticate as John Doe or as johndoe. He must authenticate as [email protected]. If you choose EA and O, John Does must authenticate as [email protected]

and

Cisco. Systems, Inc.

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Access

–

Primary DN Field—Select the primary DN field you want to configure for SMTPS authorization. The default is CN. Options include the following:

DN Field

Country (C)

Common Name (CN)

DN Qualifier (DNQ)

E-mail Address (EA)


(GENQ)

Given Name (GN)

Initials (I)

Locality (L)

Name (N)

Organization (O)

Organizational Unit

(OU)

Serial Number (SER)

Surname (SN)


Title (T)

User ID (UID)

Definition

















–

Secondary DN Field

—(Optional) Select the secondary DN field you want to configure for

SMTPS authorization. The default is OU. Options include all of those in the preceding table, with the addition of None, which you select if you do not want to include a secondary field.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Access

OL-20339-01

The E-mail Proxy Access screen lets you identify interfaces on which to configure e-mail proxy. You can configure and edit e-mail proxies on individual interfaces, and you can configure and edit e-mail proxies for one interface and then apply your settings to all interfaces. You cannot configure e-mail proxies for management-only interfaces, or for subinterfaces.


68-7

Access


Fields

•

Interface—Displays the names of all configured interfaces.

•

•

•

•

POP3S Enabled—Shows whether POP3S is enabled for the interface.

IMAP4s Enabled—Shows whether IMAP4S is enabled for the interface.

SMTPS Enabled—Shows whether SMTPS is enabled for the interface.

Edit—Click to edit the e-mail proxy settings for the highlighted interface.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

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Authentication

Edit E-Mail Proxy Access

The E-mail Proxy Access screen lets you identify interfaces on which to configure e-mail proxy. You can configure e-mail proxies on individual interfaces, and you can configure e-mail proxies for one interface and then apply your settings to all interfaces.

Fields

•

Interface—Displays the name of the selected interface.

•

POP3S Enabled—Select to enable POP3S for the interface.

•

•

•

IMAP4S Enabled—elect to enable IMAP4S for the interface.

SMTPS Enabled—Select to enable SMTPS for the interface.

Apply to all interface—Select to apply the settings for the current interface to all configured interfaces.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Authentication

This panel lets you configure authentication methods for e-mail proxy sessions.

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68-9

Authentication


Fields

POP3S/IMAP4S/SMTPS Authentication—Let you configure authentication methods for each of the e-mail proxy types. You can select multiple methods of authentication.

•

•

AAA—Select to require AAA authentication. This option requires a configured AAA server. The user presents a username, server and password. Users must present both the VPN username and the e-mail username, separated by the VPN Name Delimiter, only if the usernames are different from each other.

Certificate—Certificate authentication does not work for e-mail proxies in the current adaptive security appliance software release.

•

Piggyback HTTPS—Select to require piggyback authentication.

This authentication scheme requires a user to have already established a Clientless SSL VPN session. The user presents an e-mail username only. No password is required. Users must present both the VPN username and the e-mail username, separated by the VPN Name Delimiter, only if the usernames are different from each other.

SMTPS e-mail most often uses piggyback authentication because most SMTP servers do not allow users to log in.

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Default Servers

Note

IMAP generates a number of sessions that are not limited by the simultaneous user count but do count against the number of simultaneous logins allowed for a username. If the number of IMAP sessions exceeds this maximum and the Clientless SSL VPN connection expires, a user cannot subsequently establish a new connection. There are several solutions:

- The user can close the IMAP application to clear the sessions with the adaptive security appliance, and then establish a new Clientless SSL VPN connection.

- The administrator can increase the simultaneous logins for IMAP users (Configuration > Features >

VPN > General > Group Policy > Edit Group Policy > General).

- Disable HTTPS/Piggyback authentication for e-mail proxy.

•

Mailhost—(SMTPS only) Select to require mailhost authentication. This option appears for SMTPS only because POP3S and IMAP4S always perform mailhost authentication. It requires the user’s e-mail username, server and password.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Default Servers

This panel lets you identify proxy servers to the adaptive security appliance. Enter the IP address and port of the appropriate proxy server.

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68-11

Default Servers


Fields

•

POP3S/IMAP4S/SMTPS Default Server—Let you configure a default server, port and non-authenticated session limit for e-mail proxies.

•

Name or IP Address—Type the DNS name or IP address for the default e-mail proxy server.

•

Port—Type the port number on which the adaptive security appliance listens for e-mail proxy traffic.

Connections are automatically allowed to the configured port. The e-mail proxy allows only SSL connections on this port. After the SSL tunnel establishes, the e-mail proxy starts, and then authentication occurs.

For POP3s the default port is 995, for IMAP4S it is 993, and for SMTPS it is 988.

•

Enable non-authenticated session limit—Select to restrict the number of non-authenticated e-mail proxy sessions.

E-mail proxy connections have three states:

1.

2.

A new e-mail connection enters the “unauthenticated” state.

When the connection presents a username, it enters the “authenticating” state.

3.

When the adaptive security appliance authenticates the connection, it enters the “authenticated” state.

This feature lets you set a limit for sessions in the process of authenticating, thereby preventing DOS attacks. When a new session exceeds the set limit, the adaptive security appliance terminates the oldest non-authenticating connection. If there are no non-authenticating connections, the oldest authenticating connection is terminated. The does not terminate authenticated sessions.

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Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Delimiters

Delimiters

This panel lets you configure username/password delimiters and server delimiters for e-mail proxy authentication.

OL-20339-01

Fields

•

POP3S/IMAP4S/SMTPS Delimiters—Let you configure username/password and server delimiters for each of the e-mail proxies.

–

Username/Password Delimiter—Select a delimiter to separate the VPN username from the e-mail username. Users need both usernames when using AAA authentication for e-mail proxy and the VPN username and e-mail username are different. Users enter both usernames, separated by the delimiter you configure here, and also the e-mail server name, when they log in to an e-mail proxy session.


68-13

Delimiters


Note

Passwords for Clientless SSL VPN e-mail proxy users cannot contain characters that are used as delimiters.

–

Server Delimiter—Select a delimiter to separate the username from the name of the e-mail server. It must be different from the VPN Name Delimiter. Users enter both their username and server in the username field when they log in to an e-mail proxy session.

For example, using : as the VPN Name Delimiter and @ as the Server Delimiter, when logging in to an e-mail program via e-mail proxy, the user would enter their username in the following format: vpn_username:e-mail_username@server.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

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Configuring SSL Settings

C H A P T E R

69

SSL

The adaptive security appliance uses the Secure Sockets Layer (SSL) protocol and its successor,

Transport Layer Security (TLS) to achieve secure message transmission for both ASDM and Clientless, browser-based sessions. The SSL window lets you configure SSL versions for clients and servers and encryption algorithms. It also lets you apply previously configured trustpoints to specific interfaces, and to configure a fallback trustpoint for interfaces that do not have an associated trustpoint.

Fields

•

Server SSL Version

—Choose to specify the SSL/TLS protocol version the adaptive security appliance uses to negotiate as a server. You can make only one selection.

Options for Server SSL versions include the following:

Any

Negotiate SSL V3

Negotiate TLS V1

SSL V3 Only

TLS V1 Only

The adaptive security appliance accepts SSL version 2 client hellos, and negotiates either SSL version 3 or TLS version 1.

The adaptive security appliance accepts SSL version 2 client hellos, and negotiates to SSL version 3.

The adaptive security appliance accepts SSL version 2 client hellos, and negotiates to TLS version 1.

The security appliance accepts only SSL version 3 client hellos, and uses only SSL version 3.

The security appliance accepts only TLSv1 client hellos, and uses only TLS version 1.

Note

To use port forwarding for Clientless SSL VPN, you must select Any or Negotiate SSL V3. The issue is that JAVA only negotiates SSLv3 in the client Hello packet when you launch the Port Forwarding application.

•

Client SSL Version—

Choose to specify the SSL/TLS protocol version the adaptive security appliance uses to negotiate as a client. You can make only one selection.


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SSL

Chapter 69 Configuring SSL Settings

Options for Client SSL versions include the following: any sslv3-only tlsv1-only

The adaptive security appliance sends SSL version3 hellos, and negotiates either SSL version 3 or TLS version 1.

The security appliance sends SSL version 3 hellos, and accepts only SSL version 3.

The security appliance sends TLSv1 client hellos, and accepts only TLS version 1.

•

•

•

•

Encryption

—Lets you set SSL encryption algorithms.

–

–

Available Algorithms

—Lists the encryption algorithms the adaptive security appliance supports that are not in use for SSL connections. To use, or make active, an available algorithm, highlight the algorithm and click

Add

.

Active Algorithms

—Lists the encryption algorithms the security appliance supports and is currently using for SSL connections. To discontinue using, or change an active algorithm to available status, highlight the algorithm and click

Remove

.

–

–

Add/Remove

—Click to change the status of encryption algorithms in either the Available or

Active Algorithms columns.

Move Up/Move Down

—Highlight an algorithm and click these buttons to change its priority.

The adaptive security appliance attempts to use an algorithm

Certificates—

Lets you select a fallback certificate, and displays configured interfaces and the configured certificates associated with them.

–

Fallback Certificate

—Click to select a certificate to use for interfaces that have no certificate associated with them. If you select

None

, the adaptive security appliance uses the default RSA key-pair and certificate.

–

–

Interface

and

ID Certificate

columns—Display configured interfaces and the certificate, if any, for the interface.

Edit

—Click to change the trustpoint for the highlighted interface.

Apply—

Click to apply your changes.

Reset

—Click to remove changes you have made and reset SSL parameters to the values that they held when you opened the window.

Modes


Firewall Mode

Routed

•


Multiple


• •

Context

•

System

—

Edit SSL Certificate

Fields

•

Interface

—Displays the name of the interface you are editing.

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SSL

•

Certificate

—Click to select a previously enrolled certificate to associate with the named interface.

Modes


Firewall Mode

Routed



Multiple

Context

• • • •

System

—

SSL Certificates

In this pane, you can require that device management sessions require user certificates for SSL authentication.

Fields

•

Interface

—Displays the name of the interface you are editing.

• User Certificate Required

—Click to select a previously enrolled certificate to associate with the named interface.

Modes


Firewall Mode

Routed


Multiple


• • • •

System

—

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C H A P T E R

70

Monitoring VPN

This chapter describes how to use VPN monitoring parameters and statistics for the following:

•

VPN statistics for specific Remote Access, LAN-to-LAN, Clientless SSL VPN, and E-mail Proxy sessions

•

•

•

•

•

Encryption statistics for tunnel groups

Protocol statistics for tunnel groups

Global IPSec and IKE statistics

Crypto statistics for IPSec, IKE, SSL, and other protocols

Statistics for cluster VPN server loads

VPN Connection Graphs

Displays VPN connection data in graphical or tabular form for the adaptive security appliance.

IPSec Tunnels

Use this pane to specify graphs and tables of the IPSec tunnel types you want to view, or prepare to export or print.

Fields

•

Graph Window Title—Displays the default title that appears in the pane when you click Show

Graphs. This attribute is particularly useful when you want to clarify data in that pane before printing or exporting it. To change the title, choose an alternative from the drop-down list or type the title.

•

•

Available Graphs—Shows the types of active tunnels you can view. For each type you want to view collectively in a single pane, choose the entry and click

Add

.

Selected Graphs—Shows the types of tunnels selected.

•

If you click Show Graphs, ASDM shows the active tunnels types listed in a single pane.

A highlighted entry indicates the type of tunnel to be removed from the list if you click

Remove

.

Add—Moves the selected tunnel type from the Available Graphs column to the Selected Graphs column.


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Chapter 70 Monitoring VPN

VPN Connection Graphs

•

•

Remove—Moves the selected tunnel type from the Selected Graphs column to the Available Graphs column.

Show Graphs—Displays a pane consisting of graphs of the tunnel types displayed in the Selected

Graphs column. Each type in the pane displayed has a Graph tab and a Table tab you can click to alternate the representation of active tunnel data.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Sessions

Use this pane to specify graphs and tables of the VPN session types you want to view, or prepare to export or print.

Fields

•

Graph Window Title—Displays the default title that appears in the panepane when you click Show

Graphs. This attribute is particularly useful when you want to clarify data in that pane before printing or exporting it. To change the title, select an alternative from the drop-down list or type the title.

•

Available Graphs—Shows the types of active sessions you can view. For each type you want to view collectively in a single pane, click the entry in this box and click Add.

•

•

•

Selected Graphs—Shows the types of active sessions selected.

If you click Show Graphs, ASDM shows all of the active session types listed in this box in a single pane.

A highlighted entry indicates the type of session to be removed from the list if you click Remove.

Add—Moves the selected session type from the Available Graphs box to the Selected Graphs box.

•

Remove—Moves the selected session type from the Selected Graphs box to the Available Graphs box.

Show Graphs—Displays a pane consisting of graphs of the session types displayed in the Selected

Graphs box. Each type in the pane displayed has a Graph tab and a Table tab you can click to alternate the representation of active session data.

Modes


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Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

VPN Statistics

VPN Statistics

These panes show detailed parameters and statistics for a specific remote-access, LAN-to-LAN,

Clientless SSL VPN, or E-mail Proxy session. The parameters and statistics differ depending on the session protocol. The contents of the statistical tables depend on the type of connection you choose. The detail tables show all the relevant parameters for each session.

Sessions

Use this pane to view session statistics for the adaptive security appliance.

Fields

•

Session types (unlabeled)—Lists the number of currently active sessions of each type, the total limit, and the total cumulative session count.

–

–

Remote Access—Shows the number of remote access sessions.

Site-to-Site—Shows the number of LAN-to-LAN sessions.

•

–

SSL VPN–Clientless—Shows the number of clientless browser-based VPN sessions.

SSL VPN–With Client—Shows the number of client-based SSL VPN sessions. With ASA version

8.x and above , this represents the AnyConnect SSL VPN client 2.x and above.

–

SSL VPN–Inactive—Shows the number of SSL VPN sessions that are inactive on the remote computer.

Note

An administrator can keep track of the number of users in the inactive state and can look at the statistics. The sessions that have been inactive for the longest time are marked as idle (and are automatically logged off) so that license capacity is not reached and new users can log in. You can also access these statististics using the

show vpn-sessiondb

CLI command (refer to the

Cisco Security Appliance Command Reference Guide)

.

–

–

–

–

–

SSL VPN–Total—Shows the number of client-based and clientless SSL VPN sessions.

E-mail Proxy—Shows the number of E-mail proxy sessions.

VPN Load Balancing—Shows the number of load-balanced VPN sessions

Total—Shows the total number of active concurrent sessions.

Total Cumulative—Shows the cumulative number of sessions since the last time the adaptive security appliance was rebooted or reset.

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VPN Statistics


•

Filter By—Specifies the type of sessions that the statistics in the following table represent.

–

–

Session type (unlabeled)—Designates the session type that you want to monitor. The default is

IPSec Remote Access.

Session filter (unlabeled)—Designates which of the column heads in the following table to filter on. The default is --All Sessions--.

–

–

Filter name (unlabeled)—Specifies the name of the filter to apply. If you specify --All

Sessions-- as the session filter list, this field is not available. For all other session filter selections, this field cannot be blank.

Filter—Executes the filtering operation.

The contents of the second table, also unlabeled, in this pane depend on the selection in the Filter By list. In the following list, the first-level bullets show the Filter By selection, and the second-level bullets show the column headings for this table.

•

Remote Access—Indicates that the values in this table relate to remote access (IPsec software and hardware clients) traffic.

–

–

Username/Connection Profile—Shows the username or login name and the connection profile

(tunnel group) for the session. If the client is using a digital certificate for authentication, the field shows the Subject CN or Subject OU from the certificate.

Group Policy Connection Profile—Displays the tunnel group policy connection profile for the session.

–

Assigned IP Address/Public IP Address—Shows the private (“assigned”) IP address assigned to the remote client for this session. This is also known as the “inner” or “virtual” IP address, and it lets the client appear to be a host on the private network. Also shows the Public IP address of the client for this remote-access session. This is also known as the “outer” IP address. It is typically assigned to the client by the ISP, and it lets the client function as a host on the public network.

Note

The Assigned IP Address field does not apply to Clientless SSL VPN sessions, as the ASA

(proxy) is the source of all traffic . For a hardward client session in Network Extension mode, the Assigned IP address is the subnet of the hardware client's private/inside network interface.

•

–

–

Protocol/Encryption—Shows the protocol and the data encryption algorithm this session is using, if any.

Login Time/Duration—Shows the date and time (MMM DD HH:MM:SS) that the session logged in. and the length of the session. Time is displayed in 24-hour notation.

–

–

Client (Peer) Type/Version—Shows the type and software version number (for example, rel.

7.0_int 50) for connected clients, sorted by username.

Bytes Tx/Bytes Rx—Shows the total number of bytes transmitted to/received from the remote peer or client by the adaptive security appliance.

IPSec Site-toSite—Indicates that the values in this table relate to LAN-to-LAN traffic.

–

Connection Profile/IP Address—Shows the name of the tunnel group and the IP address of the peer.

–

–



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VPN Statistics

•

•

–

Clientless SSL VPN—Indicates that the values in this table relate to Clientless SSL VPN traffic.

–

Username/IP Address—Shows the username or login name for the session and the IP address of the client.

–


–

Group Policy Connection Profile—Displays the connection profile of the tunnel group policy.


–

–

SSL VPN Client—Indicates that the values in this table relate to traffic for SSL VPN Client sessions.

–


–



–

Group Policy Connection Profile—Displays the connection profile of the tunnel group policy.


•

–

–

E-Mail Proxy—Indicates that the values in this table relate to traffic for Clientless SSL VPN sessions.

–


–



–



–


The remainder of this section describes the buttons and fields beside and below the table.

•

•

•

Details—Displays the details for the selected session. The parameters and values differ, depending on the type of session.

Logout—Ends the selected session.

Ping—Sends an ICMP ping

(Packet Internet Groper) packet to test network connectivity.

Specifically, the adaptive security appliance sends an ICMP Echo Request message to a selected host. If the host is reachable, it returns an Echo Reply message, and the adaptive security appliance displays a Success message with the name of the tested host, as well as the elapsed time between when the request was sent and the response received. If the system is unreachable for any reason,

(for example: host down, ICMP not running on host, route not configured, intermediate router down, or network down or congested), the adaptive security appliance displays an Error screen with the name of the tested host.

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VPN Statistics


•

•

•

Logout By—Chooses a criterion to use to filter the sessions to be logged out. If you choose any but

--All Sessions--, the box to the right of the Logout By list becomes active. If you choose the value

Protocol for Logout By, the box becomes a list, from which you can choose a protocol type to use as the logout filter. The default value of this list is IPSec. For all choices other than Protocol, you must supply an appropriate value in this column.

Logout Sessions—Ends all sessions that meet the specified Logout By criteria.

Refresh—Updates the screen and its data. The date and time indicate when the screen was last updated.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Sessions Details

The Session Details pane displays configuration settings, statistics, and state information about the selected session.

The Remote Detailed table at the top of the Session Details pane displays the following columns:

•

•

Username—Shows the username or login name associated with the session. If the remote peer is using a digital certificate for authentication, the field shows the Subject CN or Subject OU from the certificate.

Group Policy and Tunnel Group—Group policy assigned to the session and the name of the tunnel group upon which the session is established.

•

•

•

•

•

•

Assigned IP Address and Public IP Address—Private IP address assigned to the remote peer for this session. Also called the inner or virtual IP address, the assigned IP address lets the remote peer appear to be on the private network. The second field shows the public IP address of the remote computer for this session. Also called the outer IP address, the public IP address is typically assigned to the remote computer by the ISP. It lets the remote computer function as a host on the public network.

Protocol/Encryption—Protocol and the data encryption algorithm this session is using, if any.

Login Time and Duration—Time and date of the session initialization, and the length of the session.

The session initialization time is in 24-hour notation.

Client Type and Version—Type and software version number (for example, rel. 7.0_int 50) of the client on the remote computer.

Bytes Tx and Bytes Rx—Shows the total number of bytes transmitted to and received from the remote peer by the adaptive security appliance.

NAC Result and Posture Token—The ASDM displays values in this column only if you configured

Network Admission Control on the adaptive security appliance.

The NAC Result shows one of the following values:

–

Accepted—The ACS successfully validated the posture of the remote host.

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VPN Statistics

–

–

–

Rejected—The ACS could not successfully validate the posture of the remote host.

Exempted—The remote host is exempt from posture validation according to the Posture

Validation Exception list configured on the adaptive security appliance.

Non-Responsive—The remote host did not respond to the EAPoUDP Hello message.

–

–

Hold-off—The adaptive security appliance lost EAPoUDP communication with the remote host after successful posture validation.

N/A—NAC is disabled for the remote host according to the VPN NAC group policy.

–

Unknown—Posture validation is in progress.

The posture token is an informational text string which is configurable on the Access Control Server.

The ACS downloads the posture token to the adaptive security appliance for informational purposes to aid in system monitoring, reporting, debugging, and logging. The typical posture token that follows the NAC result is as follows: Healthy, Checkup, Quarantine, Infected, or Unknown.

The Details tab in the Session Details panepane displays the following columns:

•

ID—Unique ID dynamically assigned to the session. The ID serves as the adaptive security appliance index to the session. It uses this index to maintain and display information about the session.

•

•

Type—Type of session: IKE, IPSec, or NAC.

Local Addr., Subnet Mask, Protocol, Port, Remote Addr., Subnet Mask, Protocol, and

Port—Addresses and ports assigned to both the actual (Local) peer and those assigned to this peer for the purpose of external routing.

•

•

•

Encryption—Data encryption algorithm this session is using, if any.

Assigned IP Address and Public IP Address—Shows the private IP address assigned to the remote peer for this session. Also called the inner or virtual IP address, the assigned IP address lets the remote peer appear to be on the private network. The second field shows the public IP address of the remote computer for this session. Also called the outer IP address, the public IP address is typically assigned to the remote computer by the ISP. It lets the remote computer function as a host on the public network.

Other—Miscellaneous attributes associated with the session.

The following attributes apply to an IKE session:

The following attributes apply to an IPSec session:

The following attributes apply to a NAC session:

–

–

Revalidation Time Interval— Interval in seconds required between each successful posture validation.

Time Until Next Revalidation—0 if the last posture validation attempt was unsuccessful.

Otherwise, the difference between the Revalidation Time Interval and the number of seconds since the last successful posture validation.

–

–

–

Status Query Time Interval—Time in seconds allowed between each successful posture validation or status query response and the next status query response. A status query is a request made by the adaptive security appliance to the remote host to indicate whether the host has experienced any changes in posture since the last posture validation.

EAPoUDP Session Age—Number of seconds since the last successful posture validation.

Hold-Off Time Remaining—0 seconds if the last posture validation was successful. Otherwise, the number of seconds remaining before the next posture validation attempt.

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VPN Statistics


–

Posture Token—Informational text string configurable on the Access Control Server. The ACS downloads the posture token to the adaptive security appliance for informational purposes to aid in system monitoring, reporting, debugging, and logging. A typical posture token is Healthy,

Checkup, Quarantine, Infected, or Unknown.

–

Redirect URL—Following posture validation or clientless authentication, the ACS downloads the access policy for the session to the adaptive security appliance. The Redirect URL is an optional part of the access policy payload. The adaptive security appliance redirects all HTTP

(port 80) and HTTPS (port 443) requests for the remote host to the Redirect URL if it is present.

If the access policy does not contain a Redirect URL, the adaptive security appliance does not redirect HTTP and HTTPS requests from the remote host.

Redirect URLs remain in force until either the IPSec session ends or until posture revalidation, for which the ACS downloads a new access policy that can contain a different redirect URL or no redirect URL.

More—Press this button to revalidate or initialize the session or tunnel group.

The ACL tab displays the ACL containing the ACEs that matched the session.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Cluster Loads

Use this pane to view the current traffic load distribution among the servers in a VPN load-balancing cluster. If the server is not part of a cluster, you receive an information message saying that this server does not participate in a VPN load-balancing cluster.

Fields

•

VPN Cluster Loads—Displays the current load distribution in the VPN load-balancing cluster.

Clicking a column heading sorts the table, using the selected column as the sort key.

–

–

Public IP Address—Displays the externally visible IP address for the server.

Role—Indicates whether this server is a master or backup device in the cluster.

–

–

Priority—Shows the priority assigned to this server in the cluster. The priority must be an integer in the range of 1 (lowest) to 10 (highest). The priority is used in the master-election process as one way to determine which of the devices in a VPN load-balancing cluster becomes the master or primary device for the cluster.

Model—Indicates the adaptive security appliance model name and number for this server.

–

–

IPSec Load %—Indicates what percentage of a server’s total capacity is in use, based upon the capacity of that server.

SSL Load %—Indicates what percentage of a SSL server’s total capacity is in use, based upon the capacity of that server.

–

IPSec Sessions—Shows the number of currently active sessions.


70-8 OL-20339-01


•

–

SSL Sessions—Shows the number of currently active sessions.

Refresh—Loads the table with updated statistics.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

VPN Statistics

Crypto Statistics

This pane displays the crypto statistics for currently active user and administrator sessions on the adaptive security appliance. Each row in the table represents one crypto statistic.

Fields

•

Show Statistics For—Selects a specific protocol, IKE Protocol (the default), IPSec Protocol, SSL

Protocol, or other protocols.

•

Statistics—Shows the statistics for all the protocols in use by currently active sessions.

•

–

–

Statistic—Lists the name of the statistical variable. The contents of this column vary, depending upon the value you select for the Show Statistics For parameter.

Value—The numerical value for the statistic in this row.

Refresh—Updates the statistics shown in the Crypto Statistics table.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Compression Statistics

This pane displays the compression statistics for currently active user and administrator sessions on the adaptive security appliance. Each row in the table represents one compression statistic.

Fields

•

Show Statistics For—Lets you select compression statistics for clientless SSL VPN or SSL VPN

Client sessions.

•

Statistics—Shows all the statistics for the selected VPN type.

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VPN Statistics


•

–


–


Refresh—Updates the statistics shown in the Compression Statistics table.

Modes


Firewall Mode

Routed



Multiple

Context

•

—

•

—

System

—

Encryption Statistics

This pane shows the data encryption algorithms used by currently active user and administrator sessions on the adaptive security appliance. Each row in the table represents one encryption algorithm type.

Fields

•

Show Statistics For—Selects a specific server or group or all tunnel groups.

•

Encryption Statistics—Shows the statistics for all the data encryption algorithms in use by currently active sessions.

–

Encryption Algorithm—Lists the encryption algorithm to which the statistics in this row apply.

–

–

Sessions—Lists the number of sessions using this algorithm.

Percentage—Indicates the percentage of sessions using this algorithm relative to the total active sessions, as a number. The sum of this column equals 100 percent (rounded).

•

•

•

Total Active Sessions—Shows the number of currently active sessions.

Cumulative Sessions—Shows the total number of sessions since the adaptive security appliance was last booted or reset.

Refresh—Updates the statistics shown in the Encryption Statistics table.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

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VPN Statistics

Global IKE/IPSec Statistics

This pane displays the global IKE/IPSec statistics for currently active user and administrator sessions on the adaptive security appliance. Each row in the table represents one global statistic.

Fields

•

Show Statistics For—Selects a specific protocol, IKE Protocol (the default) or IPSec Protocol.

•

Statistics—Shows the statistics for all the protocols in use by currently active sessions.

•

–

–



Refresh—Updates the statistics shown in the Global IKE/IPSec Statistics table.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

NAC Session Summary

The NAC Session Summary pane lets you view the active and cumulative Network Admission Control sessions.

Fields

•

Active NAC Sessions—General statistics about remote peers that are subject to posture validation.

•

Cumulative NAC Sessions—General statistics about remote peers that are or have been subject to posture validation.

•

•

•

•

Accepted—Number of peers that passed posture validation and have been granted an access policy by an Access Control Server.

Rejected—Number of peers that failed posture validation or were not granted an access policy by an Access Control Server.

Exempted—Number of peers that are not subject to posture validation because they match an entry in the Posture Validation Exception list configured on the adaptive security appliance.

Non-responsive—Number of peers not responsive to Extensible Authentication Protocol (EAP) over

UDP requests for posture validation. Peers on which no CTA is running do not respond to these requests. If the adaptive security appliance configuration supports clientless hosts, the Access

Control Server downloads the access policy associated with clientless hosts to the adaptive security appliance for these peers. Otherwise, the adaptive security appliance assigns the NAC default policy.

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VPN Statistics


•

•

•

•

Hold-off—Number of peers for which the adaptive security appliance lost EAPoUDP communications after a successful posture validation. The NAC Hold Timer attribute (Configuration

> VPN > NAC) determines the delay between this type of event and the next posture validation attempt.

N/A—Number of peers for which NAC is disabled according to the VPN NAC group policy.

Revalidate All—Click if the posture of the peers or the assigned access policies (that is, the downloaded ACLs), have changed. Clicking this button initiates new, unconditional posture validations of all NAC sessions managed by the adaptive security appliance. The posture validation and assigned access policy that were in effect for each session before you clicked this button remain in effect until the new posture validation succeeds or fails. Clicking this button does not affect sessions that are exempt from posture validation.

Initialize All—Click if the posture of the peers or the assigned access policies (that is, the downloaded ACLs) have changed, and you want to clear the resources assigned to the sessions.

Clicking this button purges the EAPoUDP associations and assigned access policies used for posture validations of all NAC sessions managed by the adaptive security appliance, and initiates new, unconditional posture validations. The NAC default ACL is effective during the revalidations, so the session initializations can disrupt user traffic. Clicking this button does not affect sessions that are exempt from posture validation.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

Protocol Statistics

This pane displays the protocols used by currently active user and administrator sessions on the adaptive security appliance. Each row in the table represents one protocol type.

Fields

•

Show Statistics For—Selects a specific server or group or all tunnel groups.

•

Protocol Statistics—Shows the statistics for all the protocols in use by currently active sessions.

–

–

Protocol—Lists the protocol to which the statistics in this row apply.

Sessions—Lists the number of sessions using this protocol.

•

•

•

–

Percentage—Indicates the percentage of sessions using this protocol relative to the total active sessions, as a number. The sum of this column equals 100 percent (rounded).

Total Active Tunnel—Shows the number of currently active sessions.

Cumulative Tunnels—Shows the total number of sessions since the adaptive security appliance was last booted or reset.

Refresh—Updates the statistics shown in the Protocol Statistics table.

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Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

VPN Statistics

VLAN Mapping Sessions

This pane displays the number of sessions assigned to an egress VLAN, as determined by the value of the Restrict Access to VLAN parameter of each group policy in use. The adaptive security appliance forwards all traffic to the specified VLAN.

Field

•

Active VLAN Mapping Sessions—Number of VPN sessions assigned to an egress VLAN.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

SSO Statistics for Clientless SSL VPN Session

This pane displays the single sign-on statistics for currently active SSO servers configured for the adaptive security appliance.

Note

These statistics are for SSO with SiteMinder and SAML Browser Post Profile servers only.

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VPN Statistics


Fields

•

Show Statistics For SSO Server—Selects an SSO server.

•

SSO Statistics—Shows the statistics for all the currently active sessions on the selected SSO server.

SSO statistics that display include:

–

–

Name of SSO server

Type of SSO server

–

–

Authentication Scheme Version (SiteMinder servers)

Web Agent URL (SiteMinder servers)

–

–

Assertion Consumer URL (SAML POST servers)

Issuer (SAML POST servers)

–

–

Number of pending requests

Number of authorization requests

–

–

Number of retransmissions

Number of accepts

–

–

–

Number of rejects

Number of timeouts

Number of unrecognized responses

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•

•

Refresh—Updates the statistics shown in the SSO Statistics table

Clear SSO Server Statistics—Resets statistics for the displayed server.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

VPN Statistics

VPN Connection Status for the Easy VPN Client

Use this panel to view the status of the adaptive security appliance configured as an Easy VPN client.

This features applies to the ASA5505 only.

Fields

VPN Client Detail—Displays configuration information for the ASA5505 configured as an Easy VPN

Client.

Connect—Establishes a client connection

Refresh—Refreshes the information displayed in the VPN Client Detail panel.

Modes


Firewall Mode

Routed

•


Multiple


—

•

Context

—

System

—

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VPN Statistics


70-16


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VPN Statistics

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VPN Statistics


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P

A R T

1 5

Monitoring

C H A P T E R

71


This chapter describes how to configure and manage logs for the adaptive security appliance and includes the following sections:

•

Information About Logging, page 71-1

•

•

•

•

•

•

Licensing Requirements for Logging, page 71-5

Prerequisites for Logging, page 71-5


Configuring Logging, page 71-6

Log Monitoring, page 71-22

Feature History for Logging, page 71-25

Information About Logging

System logging is a method of collecting messages from devices to a server running a syslog daemon.

Logging to a central syslog server helps in aggregation of logs and alerts. Cisco devices can send their log messages to a UNIX-style syslog service. A syslog service accepts messages and stores them in files, or prints them according to a simple configuration file. This form of logging is the best available for

Cisco devices, because it can provide protected long-term storage for logs. Logs are useful both in routine troubleshooting and in incident handling.

The adaptive security appliance system logs provide you with information for monitoring and troubleshooting the adaptive security appliance. With the logging feature, you can do the following:

•

Specify which syslog messages should be logged.

•

•

Disable or change the severity level of a syslog message.

Specify one or more locations where syslog messages should be sent, including an internal buffer, one or more syslog servers, ASDM, an SNMP management station, specified e-mail addresses, or to Telnet and SSH sessions.

•

•

•

•

Configure and manage syslog messages in groups, such as by severity level or class of message.

Specify whether or not a rate-limit is applied to syslog generation.

Specify what happens to the contents of the internal log buffer when it becomes full: overwrite the buffer, send the buffer contents to an FTP server, or save the contents to internal flash memory.

Filter syslog messages by locations, severity level, class, or a custom message list.


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Chapter 71 Configuring Logging



•

•

•

•

•

•

•

•

Logging in Multiple Context Mode, page 71-2

Analyzing Syslog Messages, page 71-2

Syslog Message Format, page 71-3

Severity Levels, page 71-3

Filtering Syslog Messages, page 71-4

Sorting in the Log Viewers, page 71-4

Message Classes and Range of Syslog IDs, page 71-4

Using Custom Message Lists, page 71-5

Logging in Multiple Context Mode

Each security context includes its own logging configuration and generates its own messages. If you log in to the system or admin context, and then change to another context, messages you view in your session are only those messages that are related to the current context.

Syslog messages that are generated in the system execution space, including failover messages, are viewed in the admin context along with messages generated in the admin context. You cannot configure logging or view any logging information in the system execution space.

You can configure the adaptive security appliance to include the context name with each message, which helps you differentiate context messages that are sent to a single syslog server. This feature also helps you to determine which messages are from the admin context and which are from the system; messages that originate in the system execution space use a device ID of

system

, and messages that originate in the admin context use the name of the admin context as the device ID.

Analyzing Syslog Messages

The following are some examples of the type of information you can obtain from a review of various syslog messages:

•

•

Connections that are allowed by adaptive security appliance security policies. These messages help you spot holes that remain open in your security policies.

Connections that are denied by adaptive security appliance security policies. These messages show what types of activity are being directed toward your secured inside network.

•

•

•

•

Using the ACE deny rate logging feature shows attacks that are occurring against your adaptive security appliance.

IDS activity messages can show attacks that have occurred.

User authentication and command usage provide an audit trail of security policy changes.

Bandwidth usage messages show each connection that was built and torn down, as well as the duration and traffic volume used.

•

•

Protocol usage messages show the protocols and port numbers used for each connection.

Address translation audit trail messages record NAT or PAT connections being built or torn down, which are useful if you receive a report of malicious activity coming from inside your network to the outside world.

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Syslog Message Format

Syslog messages begin with a percent sign (%) and are structured as follows:

%ASA

Level Message_number: Message_text

Field descriptions are as follows:

ASA

Level

1 through 7. The level reflects the severity of the condition described by the syslog message—the lower the number, the more severe the condition. See

Table 71-1 for

more information.

Message_number

A unique six-digit number that identifies the syslog message.

Message_text

The syslog message facility code for messages that are generated by the adaptive security appliance. This value is always ASA.

A text string that describes the condition. This portion of the syslog message sometimes includes IP addresses, port numbers, or usernames.

Severity Levels

Table 71-1

lists the syslog message severity levels. You can assign custom colors to each of the severity levels to make it easier to distinguish them in the ASDM log viewers. To configure syslog message color settings, either choose the

Tools > Preferences > Syslog

tab or, in the log viewer itself, click

Color

Settings

in the toolbar.

Table 71-1 Syslog Message Severity Levels

5

6

7

3

4

1

2

Level Number Severity Level Description

0 emergencies

System is unusable.

alert critical

Immediate action is needed.

Critical conditions.

error warning notification

Error conditions.

Warning conditions.

Normal but significant conditions.

informational

Informational messages only.

debugging

Debugging messages only.

Note

The adaptive security appliance does not generate syslog messages with a severity level of zero

(emergencies). This level is provided in the

logging

command for compatibility with the UNIX syslog feature but is not used by the adaptive security appliance.

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Message Classes and Range of Syslog IDs

For a list of syslog message classes and the ranges of syslog message IDs that are associated with each class, see the


.

Filtering Syslog Messages

You can filter generated syslog messages so that only certain syslog messages are sent to a particular output destination. For example, you could configure the adaptive security appliance to send all syslog messages to one output destination and to send a subset of those syslog messages to a different output destination.

Specifically, you can configure the adaptive security appliance so that syslog messages are directed to an output destination according to the following criteria:

•

Syslog message ID number

•

•

Syslog message severity level

Syslog message class (equivalent to a functional area of the adaptive security appliance)

You customize these criteria by creating a message list that you can specify when you set the output destination. Alternatively, you can configure the adaptive security appliance to send a particular message class to each type of output destination independently of the message list.

You can use syslog message classes in two ways:

•

•

Specify an output location for an entire category of syslog messages using the

logging class

command.

Create a message list that specifies the message class using the

logging list

command.

The syslog message class provides a method of categorizing syslog messages by type, equivalent to a feature or function of the adaptive security appliance. For example, the vpnc class denotes the VPN client.

All syslog messages in a particular class share the same initial three digits in their syslog message ID numbers. For example, all syslog message IDs that begin with the digits 611 are associated with the vpnc

(VPN client) class. Syslog messages associated with the VPN client feature range from 611101 to

611323.

In addition, most of the ISAKMP syslog messages have a common set of prepended objects to help identify the tunnel. These objects precede the descriptive text of a syslog message when available. If the object is not known at the time the syslog message is generated, the specific

heading = value

combination is not displayed.

The objects are prefixed as follows:

Group =

groupname

, Username =

user

, IP =

IP_address

, ...

Where the group identifies the tunnel-group, the username is the username from the local database or

AAA server, and the IP address is the public IP address of the remote access client or L2L peer.

Sorting in the Log Viewers

You can sort messages in all ASDM log viewers (that is, the Real-Time Log Viewer, the Log Buffer

Viewer, and the Latest ASDM Syslog Events Viewer). To sort tables by multiple columns, click the header of the first column that you want to sort by, then press and hold down the

Ctrl

key and at the same

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Licensing Requirements for Logging

time, click the headers of the other column(s) that you want to include in the sort order. To sort messages chronologically, select both the date and time columns; otherwise, the messages will be sorted only by date (regardless of the time) or only by time (regardless of the date).

When you sort messages in the Real-Time Log Viewer Viewer and in the Latest ASDM Syslog Events

Viewer, the new messages that come in appear in the sorted order, instead of at the top, as they normally would be. That is, they are mixed in with the rest of the messages.

Using Custom Message Lists

Creating a custom message list is a flexible way to exercise control over which syslog messages are sent to which output destination. In a custom syslog message list, you specify groups of syslog messages using any or all of the following criteria: severity level, message IDs, ranges of syslog message IDs, or message class.

For example, you can use message lists to do the following:

•

Select syslog messages with severity levels of 1 and 2 and send them to one or more e-mail addresses.

•

Select all syslog messages associated with a message class (such as ha) and save them to the internal buffer.

A message list can include multiple criteria for selecting messages. However, you must add each message selection criterion with a new command entry. It is possible to create a message list that includes overlapping message selection criteria. If two criteria in a message list select the same message, the message is logged only once.

Licensing Requirements for Logging


Model

All models


Base License.

Prerequisites for Logging

Logging has the following prerequisites:

•

The syslog server must run a server program called syslogd. Windows (except for Windows 95 and

Windows 98) provides a syslog server as part of its operating system. For Windows 95 and Windows

98, you must obtain a syslogd server from another vendor.

•

To view logs generated by the adaptive security appliance, you must specify a logging output destination. If you enable logging without specifying a logging output destination, the adaptive security appliance generates messages but does not save them to a location from which you can view them. You must specify each different logging output destination separately. For example, to designate more than one syslog server as an output destination, specify separate entries in the Syslog

Server pane for each syslog server.

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IPv6 Guidelines

Supports IPv6.


This section describes how to configure logging, and includes the following topics:

•

•

Enabling Logging, page 71-6

Configuring an Output Destination, page 71-7

Note

The minimum configuration depends on what you want to do and what your requirements are for handling syslog messages in the adaptive security appliance.

Enabling Logging

To enable logging, perform the following steps:

Path


•

Home > Latest ASDM Syslog Messages > Enable

Logging

•

•

Configuration > Device Management > Logging >

Logging Setup

Monitoring > Real-Time Log Viewer > Enable

Logging

• Monitoring > Log Buffer > Enable Logging

Purpose

Enables logging.

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What to Do Next

See the

“Configuring an Output Destination” section on page 71-7

.

Configuring an Output Destination

•

•

•

•

•

•

To optimize syslog message usage for troubleshooting and performance monitoring, we recommend that you specify one or more locations where syslog messages should be sent, including an internal log buffer, one or more external syslog servers, ASDM, an SNMP management station, the console port, specified e-mail addresses, or Telnet and SSH sessions.


•

•

Sending Syslog Messages to an External Syslog Server, page 71-7

Sending Syslog Messages to the Internal Log Buffer, page 71-11

Sending Syslog Messages to an E-mail Address, page 71-12

Sending Syslog Messages to the Console Port, page 71-15

•

•

•

Sending Syslog Messages to a Telnet or SSH Session, page 71-15

Creating a Custom Event List, page 71-15

Generating Syslog Messages in EMBLEM Format to a Syslog Server, page 71-16

Generating Syslog Messages in EMBLEM Format to Other Output Destinations, page 71-17

•

•

•

•

•

Changing the Amount of Internal Flash Memory Available for Logs, page 71-18

Sending All Syslog Messages in a Class to a Specified Output Destination, page 71-19

Enabling Secure Logging, page 71-19

Including the Device ID in Non-EMBLEM Format Syslog Messages, page 71-19

Including the Date and Time in Syslog Messages, page 71-20

Disabling a Syslog Message, page 71-20

Changing the Severity Level of a Syslog Message, page 71-20

Limiting the Rate of Syslog Message Generation, page 71-20

Sending Syslog Messages to an External Syslog Server

You can archive messages according to the available disk space on the external syslog server, and manipulate logging data after it is saved. For example, you could specify actions to be executed when certain types of syslog messages are logged, extract data from the log and save the records to another file for reporting, or track statistics using a site-specific script.

To send syslog messages to an external syslog server, perform the following steps:

Step 1

Step 2

Step 3

Choose

Configuration > Device Management > Logging > Logging Setup

.

Check the

Enable logging

check box to turn on logging for the main adaptive security appliance.

Check the

Enable logging on the failover standby unit

check box to turn on logging for the standby adaptive security appliance, if available.

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Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Check the

Send debug messages as syslogs

check box to redirect all debugging trace output to system logs. The syslog message does not appear on the console if this option is enabled. Therefore, to view debugging messages, you must have logging enabled at the console and have it configured as the destination for the debugging syslog message number and severity level. The syslog message number to use is

711001

. The default severity level for this syslog message is debugging.

Check the

Send syslogs in EMBLEM format

check box to enable EMBLEM format so that it is used for all log destinations, except syslog servers.

In the Buffer Size field, specify the size of the internal log buffer to which syslog messages are saved if the logging buffer is enabled. When the buffer fills up, messages will be overwritten unless you save the logs to an FTP server or to internal flash memory. The default buffer size is 4096 bytes. The range is

4096 to 1048576.

To save the buffer content to the FTP server before it is overwritten, check the

Save Buffer To FTP

Server

check box. To allow overwriting of the buffer content, uncheck this check box.

Click

Configure FTP Settings

to identify the FTP server and configure the FTP parameters used to save the buffer content. For more information, see the

“Configuring FTP Settings” section on page 71-8

.

To save the buffer content to internal flash memory before it is overwritten, check the

Save Buffer To

Flash

check box.

Note

This option is only available in routed or transparent single mode.

Step 10

Click

Configure Flash Usage

to specify the maximum space to be used in internal flash memory for logging and the minimum free space to be preserved (in KB). Enabling this option creates a directory called “syslog” on the device disk on which messages are stored. For more information, see the

“Configuring Logging Flash Usage” section on page 71-9

.

Note

This option is only available in routed or transparent single mode.

Step 11

In the Queue Size field, specify the queue size for system logs that are to be viewed in the adaptive security appliance.

Configuring FTP Settings

To specify the configuration for the FTP server that is used to save the log buffer content, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Check the

Enable FTP client

check box to enable configuration of the FTP client.

In the Server IP Address field, specify the IP address of the FTP server.

In the Path field, specify the directory path on the FTP server to store the saved log buffer content.

In the Username field, specify the username to log in to the FTP server.

In the Password field, specify the password associated with the username to log in to the FTP server.

In the Confirm Password field, reenter the password, and click

OK

.

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Configuring Logging Flash Usage

To specify the limits for saving log buffer content to internal flash memory, perform the following steps:

Step 1

Step 2

Step 3

In the Maximum Flash to Be Used by Logging field, specify the maximum amount of internal flash memory that can be used for logging (in KB).

In the Minimum Free Space to Be Preserved field, specify the amount of internal flash memory that is preserved (in KB). When the internal flash memory approaches that limit, new logs are no longer saved.

Click

OK


Configuring Syslog Messaging

To configure syslog messaging, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Choose

Configuration > Device Management > Logging > Syslog Setup

.

From the Facility code to include in syslogs drop-down list, choose a system log facility for syslog servers to use as a basis to file messages. The default is LOCAL(4)20, which is what most UNIX systems expect. However, because your network devices share eight available facilities, you might need to change this value for system logs.

To add the date and time in each syslog message sent, check the

Include timestamp in syslogs

check box.

From the Show drop-down list, choose the information to be displayed in the Syslog ID table. Available options are as follows:

•

•

To specify that the Syslog ID table should display the entire list of syslog message IDs, choose

Show all syslog IDs

.

To specify that the Syslog ID table should display only those syslog message IDs that have been explicitly disabled, choose

Show disabled syslog IDs

.

•

•

To specify that the Syslog ID table should display only those syslog message IDs with severity levels that have changed from their default values, choose

Show syslog IDs with changed logging

.

To specify that the Syslog ID table should display only those syslog message IDs with severity levels that have been modified and the IDs of syslog messages that have been explicitly disabled, choose

Show syslog IDs that are disabled or with a changed logging level

.

The Syslog ID Setup Table displays the list of syslog messages based on the setting in the Syslog ID

Setup Table. Choose individual messages or ranges of message IDs that you want to modify. You can either disable the selected message IDs or modify their severity levels. To select more than one message

ID in the list, click the first ID in the range and Shift-click the last ID in the range.

To configure syslog messages to include a device ID, click

Advanced

. For more information, see the

“Editing Syslog ID Settings” section on page 71-10

and the

“Including a Device ID in Non-EMBLEM

Formatted Syslog Messages” section on page 71-10 .

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Editing Syslog ID Settings

To change syslog message settings, perform the following steps:

Note

The Syslog ID(s) field is display-only. The values that appear in this area are determined by the entries you chose in the Syslog ID table, located in the Syslog Setup pane.

Step 1

Step 2

Check the

Disable Message(s)

check box to disable messages for the syslog message ID(s) displayed in the Syslog ID(s) list.

From the Logging Level drop-down list, choose the severity level of messages to be sent for the syslog message ID(s) displayed in the Syslog ID(s) list. Severity levels are defined as follows:

•

•

•

•

•

Emergency (level 0, system is unusable)

Alert (level 1, immediate action is needed)

Critical (level 2, critical conditions)

Error (level 3, error conditions)

•

•

•

Warning (level 4, warning conditions)

Notification (level 5, normal but significant conditions)

Informational (level 6, informational messages only)

Debugging (level 7, debugging messages only)

Note

Using a severity level of zero is not recommended.

Step 3

Click

OK


Including a Device ID in Non-EMBLEM Formatted Syslog Messages

To include a device ID in non-EMBLEM formatted syslog messages, perform the following steps:

Step 1

Step 2

Step 3

Check the

Enable syslog device ID

check box to specify that a device ID should be included in all non-EMBLEM formatted syslog messages.

To specify which to use as the device ID, choose one of the following options:

•

•

Hostname of the adaptive security appliance

Interface IP address

Choose the interface name that corresponds to the specified IP address from the drop-down list.

•

•

String

In the User-Defined ID field, specify an alphanumeric, user-defined string.

Context

Click

OK


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Sending Syslog Messages to the Internal Log Buffer

To send syslog messages to the internal log buffer, perform the following steps:


Step 1

Step 2

Path


•

•

Home > Latest ASDM Syslog Messages > Configure

ASDM Syslog Filters


Logging Filters


Logging Setup

Purpose

Specifies which syslog messages should be sent to the internal log buffer, which serves as a temporary storage location. New messages are appended to the end of the list. When the buffer is full, that is, when the buffer wraps, old messages are overwritten as new messages are generated, unless you configure the adaptive security appliance to save the full buffer to another location. To empty the internal log buffer, choose

Monitoring > Logging > Log Buffer > View

.

Then in the Log Buffer pane, choose

File > Clear

Internal Log Buffer

.

Changes the size of the internal log buffer. The buffer size is 4 KB.

Step 3



Logging Setup > Configure Flash Usage


Logging Setup > Configure FTP Settings



When saving the buffer content to another location, the adaptive security appliance creates log files with names that use the following time-stamp format:

LOG-YYYY-MM-DD-HHMMSS.TXT

where

YYYY

is the year,

MM

is the month,

DD

is the day of the month, and

HHMMSS

is the time in hours, minutes, and seconds.

The adaptive security appliance continues to save new messages to the internal log buffer and saves the full log buffer content to the internal flash memory.

When saving the buffer content to another location, the adaptive security appliance creates log files with names that use the following time-stamp format:

LOG-YYYY-MM-DD-HHMMSS.TXT

where

YYYY

is the year,

MM

is the month,

DD

is the day of the month, and

HHMMSS

is the time in hours, minutes, and seconds.

The adaptive security appliance continues saving new messages to the internal log buffer and saves the full log buffer content to an FTP server.

Identifies the FTP server on which you want to store log buffer content.



Saves the current log buffer content to the internal flash memory.

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Sending Syslog Messages to an E-mail Address

To send syslog messages to an e-mail address, perform the following steps:


Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Choose

Configuration > Device Management > Logging > E-Mail Setup

.

In the Source E-Mail Address field, specify the e-mail address that is used as the source address for syslog messages that are sent as e-mail messages.

Click

Add

to enter a new e-mail address recipient of the specified syslog messages. For more information, see the

“Adding or Editing E-Mail Recipients” section on page 71-12 .

Choose the severity level of the syslog messages that are sent to the recipient from the drop-down list.

The syslog message severity filter used for the destination e-mail address causes messages of the specified severity level and higher to be sent. The global filter specified in the Logging Filters pane is also applied to each e-mail recipient. For more information, see the

“Applying Logging Filters” section on page 71-13

.

Click

Edit

to modify an existing severity level of the syslog messages that are sent to this recipient. For more information, see the

“Adding or Editing E-Mail Recipients” section on page 71-12 .

Click

OK



“Configuring the Remote SMTP Server” section on page 71-12

.

Adding or Editing E-Mail Recipients

To add or edit e-mail recipients and severity levels, see the

“Configuring Syslog Messaging” section on page 71-9 .

Note

The severity level used to filter messages for the destination e-mail address is the higher of the severity level specified in the Add/Edit E-Mail Recipient dialog box and the global filter set for all e-mail recipients in the Logging Filters pane.

Configuring the Remote SMTP Server

To configure the remote SMTP server to which e-mail alerts and notifications are sent in response to specific events, perform the following steps:

Step 1

Step 2

Step 3

Choose

Configuration > Device Setup > Logging > SMTP

.

Enter the IP address of the primary SMTP server.

(Optional) Enter the IP address of the standby SMTP server, and click

Apply

.

Applying Message Filters to a Logging Destination

To apply message filters to a logging destination, perform the following steps:

Step 1

Choose

Configuration > Device Management > Logging > Logging Filters

.

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Step 2

Step 3

Choose the name of the logging destination to which you want to apply a filter. Available logging destinations are as follows:

•

•

•

•

•

•

ASDM

Console port

E-Mail

Internal buffer

SNMP server

Syslog server

•

Telnet or SSH session

Included in this selection are the second column, Syslogs From All Event Classes, and the third column,

Syslogs From Specific Event Classes. The second column lists the severity or the event class to use to filter messages for the logging destination, or whether logging is disabled for all event classes. The third column lists the event class to use to filter messages for that logging destination. For more information,

see the “Adding or Editing a Message Class and Severity Filter” section on page 71-14

and the

“Adding or Editing a Syslog Message ID Filter” section on page 71-15 .

Click

Edit

to display the Edit Logging Filters dialog box. To apply, edit, or disable filters, see the

“Applying Logging Filters” section on page 71-13 .

Applying Logging Filters

To apply filters, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Choose the

Filter on severity

option to filter syslog messages according to their severity level.

Choose the

Use event list

option to filter syslog messages according to an event list.

Choose the

Disable logging from all event classes

option to disable all logging to the selected destination.

Click

New

to add a new event list. To add a new event list, see the

“Creating a Custom Event List” section on page 71-15 .

Choose the event class from the drop-down list. Available event classes change according to the device mode that you are using.

Choose the level of logging messages from the drop-down list. Severity levels include the following:

•


•

•



•

•

•

•





•


Click

Add

to add the event class and severity level, and then click

OK

.

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The selected logging destination for a filter appears at the top.

Note


Adding or Editing a Message Class and Severity Filter

To add or edit a message class and severity level for filtering messages, perform the following steps:

Step 1

Step 2

Step 3


Choose the level of logging messages from the drop-down list. Severity levels include the following:

•


•

•

•

•

•

•







•


Click

OK

when you are done making selections.

Note


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Adding or Editing a Syslog Message ID Filter

To add or edit a syslog message ID filter, see the

“Adding or Editing a Syslog Message ID Filter” section on page 71-15 .

Sending Syslog Messages to the Console Port

To send syslog messages to the console port, perform the following steps:

Path


•

•




Logging Filters

Purpose

Specifies which syslog messages should be sent to the console port.

Sending Syslog Messages to a Telnet or SSH Session

To send syslog messages to a Telnet or SSH session, perform the following steps:

Step 1

Path


•



• Configuration > Device Management > Logging >

Logging Filters

Purpose

Specifies which syslog messages should be sent to a

Telnet or SSH session.

Step 2


Logging Setup

Enables logging to the current session only.

Creating a Custom Event List

You use the following three criteria to define an event list:

•

Event Class

•

•

Severity

Message ID

To create a custom list of events to send to a specific logging destination (for example, an SNMP server), perform the following steps:

Step 1

Step 2

Choose

Configuration > Device Management > Logging > Event Lists

.

Click

Add

to display the Add Event List dialog box.

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71-15



Step 3

Step 4

Step 5

Step 6

Step 7

In the Name field, enter the name of the event list. No spaces are allowed.

In the Event Class/Severity area, click

Add

to display the Add Class and Severity Filter dialog box


Choose the severity level from the drop-down list. Severity levels include the following:

•


•

•

•

•

•

•







•


Click

OK


Note


Step 8

Step 9

Step 10

In the Message ID Filters area, click

Add

to display the Add Syslog Message ID Filter dialog box.

In the Message IDs field, enter a syslog message ID or range of IDs (for example, 101001-199012) to include in the filter.

Click

OK


The event of interest appears in the list. To change this entry, click

Edit

.

Generating Syslog Messages in EMBLEM Format to a Syslog Server

To generate syslog messages in EMBLEM format to a syslog server, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Choose

Configuration > Device Management > Logging > Syslog Server

.

To add a new syslog server, click

Add

to display the Add Syslog Server dialog box. To change an existing syslog server settings, click

Edit

to display the Edit Syslog Server dialog box.

Specify the number of messages that are allowed to be queued on the adaptive security appliance when a syslog server is busy. A zero value means an unlimited number of messages may be queued.

Check the


check box to specify whether or not to restrict all traffic if any syslog server is down.


“Adding or Editing Syslog Server Settings” section on page 71-17

.

Note

You can set up a maximum of four syslog servers per security context (up to a total of 16).

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Adding or Editing Syslog Server Settings

To add or edit syslog server settings, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Choose the interface used to communicate with the syslog server from the drop-down list.

Enter the IP address that is used to communicate with the syslog server.

Choose the protocol (either TCP or UDP) that is used by the syslog server to communicate with the adaptive security appliance.

Enter the port number used by the syslog server to communicate with the adaptive security appliance.

Check the

Log messages in Cisco EMBLEM format (UDP only)

check box to specify whether to log messages in Cisco EMBLEM format (available only if UDP is selected as the protocol).

Check the

Enable secure logging using SSL/TLS (TCP only)

check box to specify that the connection to the syslog server is secure through the use of SSL/TLS over TCP, and that the syslog message content is encrypted.

Click

OK

to complete the configuration.

Generating Syslog Messages in EMBLEM Format to Other Output Destinations

To generate syslog messages in EMBLEM format to other output destinations, perform the following steps:

Path


Logging Setup

Purpose

Sends syslog messages in EMBLEM format to output destinations other than a syslog server, such as Telnet or SSH sessions.

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Changing the Amount of Internal Flash Memory Available for Logs

To change the amount of internal flash memory available for logs, perform the following steps:

Step 1

Step 2

Path

Configuration > Device Management > Logging

> Logging Setup

Configuration > Device Management > Logging

> Logging Setup

Purpose

Specifies the maximum amount of internal flash memory available for saving log files. By default, the adaptive security appliance can use up to 1 MB of internal flash memory for log data. The minimum amount of internal flash memory that must be free for the adaptive security appliance to save log data is 3

MB.

If a log file being saved to internal flash memory would cause the amount of free internal flash memory to fall below the configured minimum limit, the adaptive security appliance deletes the oldest log files to ensure that the minimum amount of memory remains free after saving the new log file. If there are no files to delete or if, after all old files have been deleted, free memory is still below the limit, the adaptive security appliance fails to save the new log file.

Specifies the minimum amount of internal flash memory that must be free for the adaptive security appliance to save a log file.

Configuring the Logging Queue

To configure the logging queue, perform the following steps:

Path


Logging Setup

Purpose

Specifies the number of syslog messages that the adaptive security appliance can hold in its queue before sending them to the configured output destination. The adaptive security appliance has a fixed number of blocks in memory that can be allocated for buffering syslog messages while they are waiting to be sent to the configured output destination. The number of blocks required depends on the length of the syslog message queue and the number of syslog servers specified. The default queue size is 512 syslog messages. The queue size is limited only by block memory availability. Valid values are from 0 to

8192 messages, depending on the platform. If the logging queue is set to zero, the queue will be the maximum configurable size (8192 messages), depending on the platform. The maximum queue size by platform is as follows:

•

•

•

ASA-5505—1024

ASA-5510—2048

On all other platforms—8192

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Sending All Syslog Messages in a Class to a Specified Output Destination

To send all syslog messages in a class to a specified output destination, perform the following steps:

Path


Logging Filters

Purpose

Overrides the configuration in the specified output destination command. For example, if you specify that messages at severity level 7 should go to the internal log buffer and that ha class messages at severity level 3 should go to the internal log buffer, then the latter configuration takes precedence. To specify that a class should go to more than one destination, choose a different filtering option for each output destination.

Enabling Secure Logging

To enable secure logging, perform the following steps:

Path Purpose

Configuration > Device Management > Logging > Syslog

Server

Enables secure logging.

Including the Device ID in Non-EMBLEM Format Syslog Messages

To include the device ID in non-EMBLEM format syslog messages, perform the following steps:

Path Purpose


Setup > Advanced

Configures the adaptive security appliance to include a device

ID in non-EMBLEM-format syslog messages. You can specify only one type of device ID for syslog messages. If you enable the logging device ID for the admin context in multiple context mode, messages that originate in the system execution space use a device ID of

system

, and messages that originate in the admin context use the name of the admin context as the device ID.

Note

If enabled, the device ID does not appear in

EMBLEM-formatted syslog messages nor in SNMP traps.

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Including the Date and Time in Syslog Messages

To include the date and time in syslog messages, perform the following steps:

Path Purpose


Setup

Specifies that syslog messages should include the date and time that they were generated.

Disabling a Syslog Message

To disable a specified syslog message, perform the following steps:

Path Purpose


Setup

Prevents the adaptive security appliance from generating a particular syslog message.

Changing the Severity Level of a Syslog Message

To change the severity level of a syslog message, perform the following steps:

Path Purpose


Setup

Specifies the severity level of a syslog message.

Limiting the Rate of Syslog Message Generation

To limit the rate of syslog message generation, perform the following steps:

Step 1

Step 2

Choose

Configuration > Device Management > Logging > Rate Limit

.

Choose the logging level (message severity level) to which you want to assign rate limits. Severity levels are defined as follows:

Description

Emergency

Alert

Critical

Error

Warning

Notification

Severity Level

0—System is unusable

1—Immediate action is needed

2—Critical conditions

3—Error conditions

4—Warning conditions

5—Normal but significant conditions

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Description

Informational

Debugging

Severity Level

6—Informational messages only

7—Debugging messages only

Step 3

The No of Messages field displays the number of messages sent. The Interval (Seconds) field displays the interval, in seconds, that is used to limit how many messages at this logging level can be sent. Choose a logging level from the table and click

Edit

to display the Edit Rate Limit for Syslog Logging Level

dialog box. To continue, see the “Assigning or Changing Rate Limits for Individual Syslog Messages” section on page 71-21

.

Assigning or Changing Rate Limits for Individual Syslog Messages

To assign or change rate limits to individual syslog messages, perform the following steps:

Step 1

Step 2

To assign the rate limit of a specific syslog message, click

Add

to display the Add Rate Limit for Syslog

Message dialog box. To continue, see the

“Adding or Editing the Rate Limit for a Syslog Message” section on page 71-21

.

To change the rate limit of a specific syslog message, click

Edit

to display the Edit Rate Limit for Syslog

Message dialog box. To continue, see the

“Editing the Rate Limit for a Syslog Severity Level” section on page 71-21 .

Adding or Editing the Rate Limit for a Syslog Message

To add or change the rate limit for a specific syslog message, perform the following steps:

Step 1

Step 2

Step 3

Step 4

To add a rate limit to a specific syslog message, click

Add

to display the Add Rate Limit for Syslog

Message dialog box. To change a rate limit for a syslog message, click

Edit

to display the Edit Rate

Limit for Syslog Message dialog box.

Enter the message ID of the syslog message that you want to limit.

Enter the maximum number of messages that can be sent in the specified time interval.

Enter the amount of time, in seconds, that is used to limit the rate of the specified message, and click

OK

.

Note

To allow an unlimited number of messages, leave both the Number of Messages and Time

Interval fields blank.

Editing the Rate Limit for a Syslog Severity Level

To change the rate limit of a specified syslog severity level, perform the following steps:

Step 1

Enter the maximum number of messages at this severity level that can be sent.

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Log Monitoring

Step 2

Enter the amount of time, in seconds, that is used to limit the rate of messages at this severity level, and click

OK

.

The selected message severity level appears.

Note

To allow an unlimited number of messages, leave both the Number of Messages and Time

Interval fields blank.

Log Monitoring


•

•

Filtering Syslog Messages Through the Log Viewers, page 71-22

Editing Filtering Settings, page 71-24

To perform log monitoring in the log buffer or in real-time and assist in monitoring system performance, perform the following steps:

Path


•

•

Monitoring > Logging > Log Buffer > View

Monitoring > Logging > Real-Time Log Viewer >

View

Purpose

Shows syslog messages, including the severity level.

Note

The maximum number of syslog messages that are available to view is 1000, which is the default setting.

The maximum number of syslog messages that are available to view is 2000.

Displays the message explanations, additional details, and recommended actions to take, if necessary, to resolve an error in a separate window. Provides text search within messages and message filtering. Allows creation of a reverse access control rule that performs the opposite action of the access control rule that originally generated the syslog message.

Reverse access control rules can be applied

only

to syslog messages 106100, 106023, 338001 through 338004, 338201, and 338202. Provides sorting of messages in each column shown. Allows detailed message filtering based on the syslog

ID, date and time, severity level, source and destination IP addresses, source and destination ports, and description listed.

Displays popup help in the Build Filter dialog box.

Filtering Syslog Messages Through the Log Viewers

You can filter syslog messages based on one or multiple values that correspond to any column of the

Real-Time Log Viewer and the Log Buffer Viewer.

To filter syslog messages through one of the log viewers, perform the following steps:

Step 1


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Log Monitoring

Step 2

Step 3

•

Monitoring > Logging > Real-Time Log Viewer > View

• Monitoring > Logging > Log Buffer > View

In either the Real-Time Log Viewer or the Log Buffer Viewer dialog box, click

Build Filter

in the toolbar.

In the Build Filter dialog box, specify the filtering criteria to apply to syslog messages:

a.

In the Date and Time area, choose one of the following three options: real-time, a specific time, or a time range. If you chose a specific time, indicate the time by entering the number and choosing hours or minutes from the drop-down list. If you chose a time range, in the Start Time field, click the drop-down arrow to display a calendar. Choose a start date and a start time from the drop-down list, then click

OK

. In the End Time field, click the drop-down arrow to display a calendar. Choose an end date and an end time from the drop-down list, then click

OK

.

b.

c.

Enter a valid severity level in the Severity field. Alternatively, click the

Edit

icon on the right of the

Severity field. In the Severity dialog box, click the severity levels in the list on which you want to filter. To include severity levels 1-7, click

All

. Click

OK

to display these settings in the Build Filter dialog box. For additional information about the correct input format to use, click the

Info

icon on the right of the Severity field.

Enter a valid syslog ID in the Syslog ID field. Alternatively, click the

Edit


Syslog ID field. In the Syslog ID dialog box, choose a condition on which to filter from the drop-down list, then click

Add

. Click

OK

to display these settings in the Build Filter dialog box.

Click

Delete

to remove these settings and enter new ones. For additional information about the correct input format to use, click the

Info

icon on the right of the Syslog ID field.

d.

e.

f.

g.

h.

Enter a valid source IP address in the Source IP Address field, or click the

Edit

icon on the right of the Source IP Address field. In the Source IP Address dialog box, choose a single IP address or a specified range of IP addresses, then click

Add

. To exclude a specific IP address or range of IP addresses, check the

Do not include (exclude) this address or range

check box. Click

OK

to display these settings in the Build Filter dialog box. Click

Delete


Info

icon on the right of the Source IP Address field.

Enter a valid source port in the Source Port field, or click the

Edit

icon on the right of the Source

Port field. In the Source Port dialog box, choose a condition on which to filter from the drop-down list, then click

Add

. Click

OK


Delete


Info

icon on the right of the Source Port field.

Enter a valid destination IP address in the Destination IP Address field, or click the

Edit

icon on the right of the Destination IP Address field. In the Destination IP Address dialog box, choose a single

IP address or a specified range of IP addresses, then click

Add

. To exclude a specific IP address or range of IP addresses, check the

Do not include (exclude) this address or range

check box. Click

OK


Delete


Info

icon on the right of the Destination IP Address field.

Enter a valid destination port in the Destination Port field, or click the

Edit


Destination Port field. In the Destination Port dialog box, choose a condition on which to filter from the drop-down list, then click

Add

. Click

OK

to display these settings in the Build Filter dialog box.

Click

Delete


Info

icon on the right of the Destination Port field.

Enter filtering text for the Description field. The text may be any string of one or more characters, including a regular expression. However, semicolons are not valid characters, and this setting is case-sensitive. Multiple entries must be separated by commas.

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Log Monitoring

Chapter 71 Configuring Logging i.

Click

OK

to add the filter settings you have just specified to the Filter By drop-down list in the log viewers. The filter strings follow a specific format. The prefix FILTER: designates all custom filters that appear in the Filter By drop-down list. You may still type random text into this field.

The following table shows examples of the format used.

Build Filter Example

Source IP = 192.168.1.1 or 0.0.0.0

Source Port = 67

Severity = Informational

Destination IP = 1.1.1.1 through 1.1.1.10

Syslog ID not in the range 725001 through

725003

Source IP = 1.1.1.1

Description = Built outbound

Filter String Format

FILTER: srcIP=192.168.1.1,0.0.0.0;srcPort=67;

FILTER: sev=6;dstIP=1.1.1.1-1.1.1.10;

FILTER: sysID=!725001-725003;

FILTER: srcIP=1.1.1.1;descr=Built outbound

Step 4

To filter syslog messages, choose one of the settings in the Filter By drop-down list, then click

Filter

in the toolbar. This setting also applies to all future syslog messages. To clear all filters, click

Show All

in the toolbar.

Note

You cannot save filters that you have specified with the Build Filter dialog box. These filters are valid only for the ASDM session during which they were created.

Editing Filtering Settings

To edit filtering settings that you created using the Build Filter dialog box, perform the following steps:


•

•

Revise a filter directly by entering the changes in the Filter By drop-down list.

Choose a filter in the Filter By drop-down list, then click

Build Filter

to display the Build Filter dialog box. To remove the current filter settings and enter new ones, click

Clear Filter

. Otherwise, change the settings that appear, and click

OK

.

Note

These filter settings apply only to those defined in the Build Filter dialog box.

•

To stop filtering and show all syslog messages, click

Show All

in the toolbar.

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Feature History for Logging


Table 71-2


Table 71-2 Feature History for Logging

Feature Name

Logging

Rate limit

Logging list

Secure logging

Logging class

Logging class and saved logging buffers

Password encryption

Platform

Releases

7.0(1)

7.0(4)

7.2(1)


Provides adaptive security appliance network logging information through various output destinations, and includes the option to view and save log files.

The Configuration > Device Management > Logging > Logging Setup screen was introduced.

Limits the rate at which syslog messages are generated.

The Configuration > Device Management > Logging > Rate Limit screen was modified.

Creates a logging list to use in other commands to specify messages by various criteria (logging level, event class, and message IDs).

8.0(2)

The Configuration > Device Management > Logging > Event Lists screen was modified.

Specifies that the connection to the remote logging host should use SSL/TLS.

This option is valid only if the protocol selected is TCP.

The Configuration > Device Management > Logging > Syslog Server screen was modified.

8.0(4), 8.1(1) Added support for the ipaa event class of logging messages.

8.2(1)

The Configuration > Device Management > Logging > Logging Filters screen was modified.

Added support for the dap event class of logging messages.

8.3(1)

Added support to clear the saved logging buffers (ASDM, internal, FTP, and flash).

The Configuration > Device Management > Logging > Logging Setup screen was modified.

Added support for password encryption.

Log viewers 8.3(1) The source and destination IP addresses were added to the log viewers.

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71-25



Table 71-2 Feature History for Logging (continued)

Feature Name

Syslog message filtering and sorting

Platform

Releases

8.3(2)

Enhanced logging and connection blocking

8.3(2)


Support has been added for the following:

•

•

Syslog message filtering based on multiple text strings that correspond to various columns

Creation of custom filters

•

Column sorting of messages. For detailed information, see the

Cisco ASA

5500 Series Configuration Guide using ASDM

.


Monitoring > Logging > Real-Time Log Viewer > View

Monitoring > Logging > Log Buffer Viewer > View

This feature interoperates with all ASA versions.

When you configure a syslog server to use TCP, and the syslog server is unavailable, the adaptive security appliance blocks new connections that generate syslog messages until the server becomes available again (for example,

VPN, firewall, and cut-through-proxy connections). This feature has been enhanced to also block new connections when the logging queue on the adaptive security appliance is full; connections resume when the logging queue is cleared.

This feature was added for compliance with Common Criteria EAL4+. Unless required, we recommended allowing connections when syslog messages cannot be sent or received. To allow connections, continue to check the


check box on the Configuration

> Device Management > Logging > Syslog Servers pane.

The following syslog messages were introduced: 414005, 414006, 414007, and

414008.

No ASDM screens were modified.

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C H A P T E R

72

Configuring

NetFlow Secure Event Logging (NSEL)

This chapter describes how to configure NSEL, a security logging mechanism that is built on NetFlow

Version 9 technology, and how to handle events and syslog messages through NSEL.


•

•

•

•

•

Information About NSEL, page 72-1

Licensing Requirements for NSEL, page 72-3

Prerequisites for NSEL, page 72-3


•

•

•

•

Configuring NSEL, page 72-4

Monitoring NSEL, page 72-6



Feature History for NSEL, page 72-8

Information About NSEL

The adaptive security appliance supports NetFlow Version 9 services. For more information about

NetFlow services, see

RFCs, page 72-8 .

The adaptive security appliance implementation of NSEL is a stateful, IP flow tracking method that exports only those records that indicate significant events in a flow. In stateful flow tracking, tracked flows go through a series of state changes. NSEL events are used to export data about flow status, and are triggered by the event that caused the state change.

The significant events that are tracked include flow-create, flow-teardown, and flow-denied (excluding those flows that are denied by EtherType ACLs). Each NSEL record has an event ID and an extended event ID field, which describes the flow event.

The adaptive security appliance implementation of NSEL provides the following major functions:

•

•

Keeps track of flow-create, flow-teardown, and flow-denied events, and generates appropriate NSEL data records.

Defines and exports templates that describe the progression of a flow. Templates describe the format of the data records that are exported through NetFlow. Each event has several record formats or templates associated with it.


72-1 OL-20339-01

Chapter 72 Configuring NetFlow Secure Event Logging (NSEL)

Information About NSEL

•

•

•

•

Tracks configured NSEL collectors and delivers templates and data records to these configured

NSEL collectors through NetFlow over UDP only.

Sends template information periodically to NSEL collectors. Collectors receive template definitions, normally before receiving flow records.

Filters NSEL events based on the traffic and event type through Modular Policy Framework, and then sends records to different collectors. Traffic is matched based on the order in which classes are configured. After a match is found, no other classes are checked. The supported event types are flow-create, flow-denied, flow-teardown, and all. Records can be sent to different collectors. For example, with two collectors, you can do the following:

–

–

Log all flow-denied events that match access-list 1 to collector 1.

Log all flow-create events to collector 1.

–

Log all flow-teardown events to collector 2.

Delays the export of flow-create events.

Using NSEL and Syslog Messages

Table 72-1 lists the syslog messages that have an equivalent NSEL event, event ID, and extended event

ID. The extended event ID provides more detail about the event (for example, which ACL—ingress or egress—has denied a flow).

Note

Enabling NetFlow to export flow information makes the syslog messages that are listed in

Table 72-1

redundant. In the interest of performance, we recommend that you disable redundant syslog messages, because the same information is exported through NetFlow.

Table 72-1

Syslog Message

106100

106015

106023

302013, 302015,

302017, 302020

302014, 302016,

302018, 302021

Syslog Messages and Equivalent NSEL Events

Description

Generated whenever an ACL is encountered.

A TCP flow was denied because the first packet was not a SYN packet.

When a flow was denied by an

ACL attached to an interface through the

access-group

command.

TCP, UDP, GRE, and ICMP connection creation.

TCP, UDP, GRE, and ICMP connection teardown.

NSEL Event ID

1—Flow was created (if the

ACL allowed the flow).

NSEL Extended Event ID

0—If the ACL allowed the flow.

3—Flow was denied (if the

ACL denied the flow).

1001—Flow was denied by the ingress ACL.

1002—Flow was denied by the egress ACL.

3—Flow was denied.


1—Flow was created.

2—Flow was deleted.

1004—Flow was denied because the first packet was not a TCP

SYN packet.

1001—Flow was denied by the ingress ACL.

1002—Flow was denied by the egress ACL.

0—Ignore.

0—Ignore.

> 2000—Flow was torn down.

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Table 72-1

Syslog Message

313001

313008

710003

Syslog Messages and Equivalent NSEL Events (continued)

Description

An ICMP packet to the device was denied.

NSEL Event ID


An ICMP v6 packet to the device was denied.


An attempt to connect to the device interface was denied.


Licensing Requirements for NSEL

NSEL Extended Event ID

1003—To-the-box flow was denied because of configuration.



Note

When NSEL and syslog messages are both enabled, there is no guarantee of chronological ordering between the two logging types.

Licensing Requirements for NSEL


Model

All models


Base License.

Prerequisites for NSEL

NSEL has the following prerequisites:

•

IP address and hostname assignments must be unique throughout the NetFlow configuration.

•

•

You must have at least one configured collector before you can use NSEL.

You must configure NSEL collectors before you can configure filters via Modular Policy

Framework.







IPv6 Guidelines

Supports IPv6 for the

class-map

,


, and

match any

commands.

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72-3

Configuring NSEL



•

If you previously configured flow-export actions using the

flow-export enable

command, and you upgrade to a later version, then your configuration will be automatically converted to the new

Modular Policy Framework

flow-export event-type

command, described under the

policy-map

command. For more information, see the

Release Notes for the Cisco ASA 5500 Series

for Version

8.1(2).

•

Flow-export actions are not supported in interface-based policies. You can configure flow-export actions in a class-map

only

with the


,

match any

, or

class-default

commands. You can

only

apply flow-export actions in a global service policy.

Configuring NSEL

This section describes how to configure NSEL, and includes the following topics:

•

•

Using NetFlow, page 72-4

Matching NetFlow Events to Configured Collectors, page 72-5

Using NetFlow

The NetFlow pane lets you enable the transmission of data about a flow of packets. To access this pane, choose

Configuration > Device Management > Logging > NetFlow

.

Note

IP address and hostname assignments should be unique throughout the NetFlow configuration.

To use NetFlow, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Enter the template timeout rate, which is the interval (in minutes) at which template records are sent to all configured collectors. The default value is 30 minutes.

To delay the export of flow-creation events and process a single flow-teardown event instead of a flow-creation event and a flow-teardown event, check the

Delay export of flow creation events for short-lived flows

check box, and then enter the number of seconds for the delay in the Delay By field.

Specify the collector(s) to which NetFlow packets will be sent. You can configure a maximum of five collectors. To configure a collector, click

Add

to display the Add NetFlow Collector dialog box, and perform the following steps:

a.

b.

Choose the interface to which NetFlow packets will be sent from the drop-down list.

Enter the IP address or hostname and the UDP port number in the associated fields.

c.

Click

OK

.

To configure more collectors, repeat

Step 2

for each additional collector.

To change collector configuration details, select a collector and click

Edit

. To remove a configured collector, select it and click

Delete

.

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Using NetFlow

Step 6

Step 7

When NetFlow is enabled, certain syslog messages become redundant. To maintain system performance, we recommend that you disable all redundant syslog messages, because the same information is exported through NetFlow. To disable all redundant syslog messages, check the

Disable redundant syslog messages

check box. To display the redundant syslog messages and their status, click

Show Redundant

Syslog Messages

.

The Redundant Syslog Messages dialog box appears. The Syslog ID field displays the redundant syslog message numbers. The Disabled field indicates whether or not the specified syslog message is disabled.

Click

OK


To disable individual redundant syslog messages, choose

Configuration > Device Management >

Logging > Syslog Setup

.

Click

Apply

to save your changes. Click

Reset

to enter new settings.

What to Do Next

See the

“Matching NetFlow Events to Configured Collectors” section on page 72-5 .

Matching NetFlow Events to Configured Collectors

After you configure NetFlow collectors, you can match a NetFlow event with any of these configured collectors.

To specify which NetFlow events should be sent to which collector, perform the following steps:

Step 1

Step 2



.

To add a service policy rule, perform the following steps:

a.

b.

Click

Add

to display the Add Service Policy Rule Wizard. For more information about service policy rules, see the

“Adding a Service Policy Rule for Through Traffic” section on page 29-8 .

Click the


radio button to apply the rule to the global policy. Click

Next

.

c.

Check the


check box or the

Any traffic

check box as traffic match criteria, or click the

Use class-default as traffic class

radio button. Click

Next

to continue to the Rule Actions screen.

Note

NetFlow actions are available only for global service policy rules and are applicable only to the class-default traffic class and to traffic classes with traffic match criteria of “Source and

Destination IP Address (uses ACL)” or “Any traffic.”

Step 3

Step 4

In the Rule Actions screen, click the

NetFlow

tab.

To specify flow events, click

Add

to display the Add Flow Event dialog box, and then perform the following steps:

a.

b.

Choose the flow event type from the drop-down list. Available events are created, torn down, denied, or all.

Choose collectors to which you want events sent by checking the corresponding check boxes in the

Send column.

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72-5


Monitoring NSEL

Step 5

Step 6

Step 7

Step 8 c.

To add, edit or delete collectors, or to configure other NetFlow settings (for example, syslog messages), click

Manage

to display the Manage NetFlow Collectors dialog box. Click

OK

to close the Manage NetFlow Collectors dialog box and return to the Add Flow Event dialog box. For more information about configuring collectors, see

Step 3 of the “Using NetFlow” section on page 72-4 .

Click

OK

to close the Add Flow Event dialog box and return to the NetFlow tab.

To change flow event entries, select an entry from the list, and click

Edit

. To remove flow event entries, select an entry from the list, and click

Delete

.

Click

Finish

to exit the wizard.

To edit a NetFlow service policy rule, perform the following steps:

a.

b.

Select it in the Service Policy Rules table, and click

Edit

.

Click the Rule Actions tab, and then click the NetFlow tab.

See the

“Monitoring NSEL” section on page 72-6 .

Monitoring NSEL

You can use syslog messages to help troubleshoot errors or monitor system usage and performance.You can view real-time syslog messages that have been saved in the log buffer in a separate window, which include an explanation of the message, details about the message, and recommended actions to take, if necessary, to resolve an error. For more information, see the

“Using NSEL and Syslog Messages” section on page 72-2

.

To monitor NSEL, see the following pane:

Path


Type

show flow-export counters

, then press

Send

.


Type

show logging flow-export-syslogs

, then press

Send

.


Type

show running-config logging

, then press

Send

.

Purpose

Shows runtime counters, including statistical data and error data, for NSEL.

Lists all syslog messages that are captured by NSEL events.

Shows disabled syslog messages, which are redundant syslog messages, because they export the same information through

NetFlow.





For additional information related to implementing NSEL, see the following sections:

•


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•

RFCs, page 72-8


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Feature History for NSEL


Related Topic

Using NSEL and Syslog Messages, page 72-2

Document Title


Information about the implementation of NSEL on the adaptive security appliance

Cisco ASA 5500 Series Implementation Note for NetFlow Collectors

RFCs

RFC

3954

Title

Cisco Systems NetFlow Services Export Version 9




Table 72-2

Feature Name

NetFlow

NetFlow

Filtering

NSEL

Feature History for NSEL

Platform

Releases

8.1(1)

8.1(2)

8.2(1)


The NetFlow feature enhances the adaptive security appliance logging capabilities by logging flow-based events through the NetFlow protocol. NetFlow Version 9 services are used to export information about the progression of a flow from start to finish. The

NetFlow implementation exports records that indicate significant events in the life of a flow. This implementation is different from traditional NetFlow, which exports data about flows at regular intervals. The NetFlow module also exports records about flows that are denied by access lists. You can configure an ASA 5580 to send the following events using

NetFlow: flow create, flow teardown, and flow denied (only flows denied by ACLs are reported).

The following screen was introduced:

Configuration > Device Management > Logging > NetFlow

.

You can filter NetFlow events based on traffic and event-type, and then send records to different collectors. For example, you can log all flow-create events to one collector, and log flow-denied events to a different collector.

For short-lived flows, NetFlow collectors benefit from processing a single event instead of two events: flow create and flow teardown. You can configure a delay before sending the flow-create event. If the flow is torn down before the timer expires, only the flow teardown event is sent. The teardown event includes all information regarding the flow; no loss of information occurs.

The following screen was modified:


.

The NetFlow feature has been ported to all ASA 5500 series adaptive security appliances.

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C H A P T E R

73


This chapter describes how to configure SNMP to monitor the adaptive security appliance and includes the following sections:

•

Information about SNMP, page 73-1

•

•

•

•

•

Licensing Requirements for SNMP, page 73-4

Prerequisites for SNMP, page 73-5


Configuring SNMP, page 73-6

•

•



Feature History for SNMP, page 73-14

Information about SNMP

SNMP is an application-layer protocol that facilitates the exchange of management information between network devices. It is part of the TCP/IP protocol suite. This section describes SNMP monitoring, and includes the following topics:

•

Information About SNMP Terminology, page 73-2

•

Information About MIBs and Traps, page 73-2

The adaptive security appliance provides support for network monitoring using SNMP Versions 1, 2c, and 3, and supports the use of all three versions simultaneously. The SNMP interface lets you monitor the adaptive security appliance through network management systems (NMSs), such as HP OpenView.

The adaptive security appliance supports SNMP read-only access through issuance of a GET request.

SNMP write access is not allowed, so you cannot make changes with SNMP. In addition, the SNMP SET request is not supported.

You can configure the adaptive security appliance to send traps, which are unsolicited comments from the managed device to the management station for certain events (event notifications) to an NMS, or you can use the NMS to browse the MIBs on the adaptive security appliance. MIBs are a collection of definitions, and the adaptive security appliance maintains a database of values for each definition.

Browsing a MIB means issuing a series of GET-NEXT or GET-BULK requests of the MIB tree from the

NMS to determine values.


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Chapter 73 Configuring SNMP


The adaptive security appliance has an SNMP agent that notifies designated management stations if events occur that are pre-defined to require a notification, for example, when a link in the network goes up or down. The notification it sends includes an SNMP OID, which identifies itself to the management stations. The adaptive security appliance SNMP agent also replies when a management station asks for information.

Information About SNMP Terminology

Table 73-1 lists the terms that are commonly used when working with SNMP:

Table 73-1 SNMP Terminology

Term

Agent

Browsing

Management

Information

Bases (MIBs)

Description

The SNMP server running on the adaptive security appliance. The agent responds to requests for information and actions from the network management station. The agent also controls access to its Management Information Base, the collection of objects that the SNMP manager can view or change.

Monitoring the health of a device from the network management station by polling required information from the SNMP agent on the device. This activity may include issuing a series of GET-NEXT or GET-BULK requests of the MIB tree from the network management station to determine values.

Standardized data structures for collecting information about packets, connections, buffers, failovers, and so on. MIBs are defined by the product, protocols ,and hardware standards used by most network devices. SNMP network management stations can browse MIBs and request specific data or events be sent as they occur.

Some MIB data can be modified for administrative purposes.

The PCs or workstations set up to monitor SNMP events and manage devices, such as the adaptive security appliance.

Network management stations (NMSs)

Object identifier

(OID)

Trap

The system that identifies a device to its NMS and indicates to users the source of information monitored and displayed.

Predefined events that generate a message from the SNMP agent to the NMS.

Events include alarm conditions such as linkup, linkdown, coldstart, authentication, or syslog events.

Information About MIBs and Traps

MIBs are either standard or enterprise-specific. Standard MIBs are created by the IETF and documented in various RFCs. A trap reports significant events occurring on a network device, most often errors or failures. SNMP traps are defined in either standard or enterprise-specific MIBs. Standard traps are created by the IETF and documented in various RFCs. Standard traps are compiled into the adaptive security appliance software.

If needed, you can also download RFCs, standard MIBs, and standard traps from the IETF website: http://www.ietf.org/

Download Cisco MIBs and OIDs from the following location: http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml

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Download Cisco OIDs from the following location: ftp://ftp.cisco.com/pub/mibs/oid/oid.tar.gz


Note

In software versions 7.2(1), 8.0(2), and later, the interface information accessed via SNMP refreshes about every five seconds. As a result, we recommend that you wait for at least five seconds between consecutive polls.

SNMP Version 3

This section describes SNMP Version 3 and includes the following topics:

•

•

•

SNMP Version 3 Overview, page 73-3

Security Models, page 73-3

SNMP Groups, page 73-4

•

•

•

SNMP Users, page 73-4

SNMP Hosts, page 73-4

Implementation Differences Between Adaptive Security Appliances and the Cisco IOS, page 73-4

SNMP Version 3 Overview

SNMP Version 3 provides security enhancements that are not available in SNMP Version 1 or SNMP

Version 2c. SNMP Versions 1 and 2c transmit data between the SNMP server and SNMP agent in clear text. SNMP Version 3 adds authentication and privacy options to secure protocol operations. In addition, this version controls access to the SNMP agent and MIB objects through the User-based Security Model

(USM) and View-based Access Control Model (VACM). The ASA 5500 series adaptive security appliances also support the creation of SNMP groups and users, as well as hosts, which is required to enable transport authentication and encryption for secure SNMP communications.

Security Models

For configuration purposes, the authentication and privacy options are grouped together into security models. Security models apply to users and groups, which are divided into the following three types:

•

NoAuthPriv—No Authentication and No Privacy, which means that no security is applied to messages.

•

•

AuthNoPriv—Authentication but No Privacy, which means that messages are authenticated.

AuthPriv—Authentication and Privacy, which means that messages are authenticated and encrypted.

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Licensing Requirements for SNMP

SNMP Groups

An SNMP group is an access control policy to which users can be added. Each SNMP group is configured with a security model, and is associated with an SNMP view. A user within an SNMP group must match the security model of the SNMP group. These parameters specify what type of authentication and privacy a user within an SNMP group uses. Each SNMP group name and security model pair must be unique.

SNMP Users

SNMP users have a specified username, a group to which the user belongs, authentication password, encryption password, and authentication and encryption algorithms to use. The authentication algorithm options are MD5 and SHA. The encryption algorithm options are DES, 3DES, and AES (which is available in 128, 192, and 256 versions). When you create a user, you must associate it with an SNMP group. The user then inherits the security model of the group.

SNMP Hosts

An SNMP host is an IP address to which SNMP notifications and traps are sent. To configure SNMP

Version 3 hosts, along with the target IP address, you must configure a username, because traps are only sent to a configured user. SNMP target IP addresses and target parameter names must be unique on the adaptive security appliance. Each SNMP host can have only one username associated with it. To receive

SNMP traps, configure the SNMP NMS, and make sure that you configure the user credentials on the

NMS to match those configured on the adaptive security appliance.

Implementation Differences Between Adaptive Security Appliances and the Cisco IOS

The SNMP Version 3 implementation in adaptive security appliances differs from the SNMP Version 3 implementation in the Cisco IOS in the following ways:

•

•

•

•

•

The local-engine and remote-engine IDs are not configurable. The local engine ID is generated when the adaptive security appliance starts or when a context is created.

No support exists for view-based access control, which results in unrestricted MIB browsing.

Support is restricted to the following MIBs: USM, VACM, FRAMEWORK, and TARGET.

You must create users and groups with the correct security model.

•

You must remove users, groups, and hosts in the correct sequence.

Use of the

snmp-server host

command creates an adaptive security appliance rule to allow incoming SNMP traffic.

Licensing Requirements for SNMP


Model

All models


Base License.

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Prerequisites for SNMP

Prerequisites for SNMP

SNMP has the following prerequisite:

You must have Cisco Works for Windows or another SNMP MIB-II compliant browser to receive SNMP traps or browse a MIB.







•

Supported in SNMP Version 3.

•

The SNMP client in each adaptive security appliance shares engine data with its peer. Engine data includes the engineID, engineBoots, and engineTime objects of the SNMP-FRAMEWORK-MIB.

IPv6 Guidelines


•

•

•


•

Does not support view-based access control, but the VACM MIB is available for browsing to determine default view settings.

•

Does not support SNMP Version 3 for the AIP SSM or AIP SSC.

•

•

Does not support SNMP debugging.

When using NET-SNMP Version 5.4.2.1, only supports the encryption algorithm version of

AES128. Does not support the encryption algorithm versions of AES246 or AES192.

For SNMP Version 3, configuration must occur in the following order: group, user, host.

Before a group is deleted, you must ensure that all users associated with that group are deleted.

•

•

•

Before a user is deleted, you must ensure that no hosts are configured that are associated with that username.

If users have been configured to belong to a particular group with a certain security model, and if the security level of that group is changed, you must do the following in this sequence:

–

–

Remove the users from that group.

Change the group security level.

–

Add users that belong to the new group.

The creation of custom views to restrict user access to a subset of MIB objects is not supported.

All requests and traps are available in the default Read/Notify View

only

.

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This section describes how to configure SNMP and includes the following topics:

•

Enabling SNMP, page 73-6

•

•

•

•

•

Configuring an SNMP Management Station, page 73-6

Configuring SNMP Traps, page 73-7

Compiling Cisco Syslog MIB Files, page 73-8

Using SNMP Version 1 or 2c, page 73-9

Using SNMP Version 3, page 73-9

Enabling SNMP

The SNMP agent that runs on the adaptive security appliance performs two functions:

•

•

Replies to SNMP requests from NMSs.

Sends traps (event notifications) to NMSs.

To enable the SNMP agent and identify an NMS that can connect to the SNMP server, see the following pane:

Path Purpose

Configuration > Device Management

> Management Access > SNMP

Ensures that the SNMP server on the adaptive security appliance is enabled. By default, the SNMP server is enabled.

What to Do Next

See the

“Configuring an SNMP Management Station” section on page 73-6 .

Configuring an SNMP Management Station

To receive requests from the adaptive security appliance. you must configure an SNMP management station in ASDM.

To configure an SNMP management station, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Choose

Configuration > Device Management > Management Access > SNMP

.

In the SNMP Management Stations pane, click

Add

.

The Add SNMP Host Access Entry dialog box appears.

From the Interface Name drop-down list, choose the interface on which the SNMP host resides.

In the IP Address field, enter the SNMP host IP address.

In the UDP Port field, enter the SNMP host UDP port, or keep the default, port 162.

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Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

In the Community String field, add the SNMP host community string. If no community string is specified for a management station, the value set in the Community String (default) field on the SNMP

Management Stations pane is used.

From the SNMP Version drop-down list, choose the SNMP version used by the SNMP host.

If you have selected SNMP Version 3 in the previous step, from the Username drop-down list, choose the name of a configured user.

To specify the method for communicating with this NMS, check either the

Poll

or

Trap

check box.

Click

OK

.

The Add SNMP Host Access Entry dialog box closes.

Click

Apply

.

The NMS is configured and changes are saved to the running configuration. For more information about

SNMP Version 3 NMS tools, go to the following URL: http://www.cisco.com/en/US/docs/security/asa/asa82/snmp/snmpv3_tools.html

What to Do Next

See the

“Configuring SNMP Traps” section on page 73-7 .

Configuring SNMP Traps

To designate which traps the SNMP agent generates and how they are collected and sent to NMSs, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Choose


.

Click

Configure Traps

.

The SNMP Trap Configuration dialog box appears.

Check the applicable check boxes for the SNMP events to notify through SNMP traps.

Click

OK

.

The SNMP Trap Configuration dialog box closes.

Click

Apply

.

The SNMP traps are configured and the changes are saved to the running configuration.

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What to Do Next

See the

“Compiling Cisco Syslog MIB Files” section on page 73-8 .

Compiling Cisco Syslog MIB Files

To receive security and failover SNMP traps from the adaptive security appliance, compile the Cisco

SMI MIB and the Cisco Syslog MIB into the SNMP management application. If you do not compile the

Cisco Syslog MIB into your application, you only receive traps for linkup or linkdown, coldstart, and authentication failure.

To compile Cisco Syslog MIB files into your browser using Cisco Works for Windows, perform the following steps:

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 1

Step 2

To download the Cisco MIBs, go to the following URL: http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml

From the Cisco Secure and VPN Products drop-down list, choose

adaptive security appliance

.

The Adaptive Security Appliance MIB Support List appears.

Click

CISCO-SYSLOG-MIB.my

, and save the file to your desktop.

Start CiscoWorks for Windows.

Choose

Config > Compile MIB

.

Scroll to the bottom of the list, and click the last entry.

Click

Add

.

Locate the Cisco Syslog MIB files.

Note

You must manually rename any files with the .my extension to the .mib extension, because only files with the .mib extension appear in the file selection window of CiscoWorks for Windows.

Step 9

Step 10

Step 11

Step 12

Step 13

Step 14

Step 15

Step 16

Step 17

Step 18

Step 19

Step 20

Click

CISCO-FIREWALL-MIB.mib

, and click

OK

.


Click

Add

.

Click

CISCO-MEMORY-POOL-MIB.mib

, and click

OK

.


Click

Add

.

Click

CISCO-SMI-MIB.mib

, and click

OK

.


Click

Add

.

Click

CISCO-SYSLOG-MIB.mib

, and click

OK

.

Click

Load All

.

If no errors occur, restart Cisco Works for Windows.

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What to Do Next


•

•

See the

“Using SNMP Version 1 or 2c” section on page 73-9

.

See the

“Using SNMP Version 3” section on page 73-9 .

Using SNMP Version 1 or 2c

To configure parameters for SNMP Version 1 or 2c, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Choose


.

(Optional) Enter a default community string in the Community String (default) field.

Enter the password used by the SNMP NMSs when sending requests to the adaptive security appliance.

The SNMP community string is a shared secret among the SNMP NMSs and the network nodes being managed. The adaptive security appliance uses the password to determine if the incoming SNMP request is valid. The password is a case-sensitive value up to 32 characters in length. Spaces are not permitted.

The default is “public.” SNMP Version 2c allows separate community strings to be set for each NMS. If no community string is configured for any NMS, the value set here will be used by default.

In the Contact field, enter the name of the adaptive security appliance system administrator. The text is case-sensitive and can be up to 127 characters. Spaces are accepted, but multiple spaces are shortened to a single space.

In the ASA Location field, enter the location of the adaptive security appliance being managed by SNMP.

The text is case-sensitive and can be up to 127 characters. Spaces are accepted, but multiple spaces are shortened to a single space.

In the Listening Port field, enter the number of the adaptive security appliance port that listens for SNMP requests from NMSs; or keep the default, port number161.

Click

Apply

.

SNMP parameters for Versions 1 and 2c are configured and the changes are saved to the running configuration.

What to Do Next

See the

“Monitoring SNMP” section on page 73-10

.

Using SNMP Version 3

To configure parameters for SNMP Version 3, perform the following steps:

Step 1

Step 2

Choose


.

In the SNMPv3 Users pane, to add a configured user or a new user to a group, click

Add

. To change user parameters, click

Edit

. To remove a configured user from a group, click

Delete

. When you remove the last user in a group, ASDM deletes the group.

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Monitoring SNMP

Note

After a user has been created, you cannot change the group to which the user belongs.

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Step 12

The Add SNMP User Entry dialog box appears.

From the Group Name drop-down list, choose the group to which the SNMP user will belong. The available groups are as follows:

•

•

Auth&Encryption, in which users have authentication and encryption configured

Authentication_Only, in which users have only authentication configured

•

No_Authentication, in which users have neither authentication nor encryption configured

In the Username field, enter the name of a configured user or a new user. The username must be unique for the SNMP server group selected.

Indicate the type of password you want to use by clicking one of the two radio buttons:

Encrypted

or

Clear Text

.

Indicate the type of authentication you want to use by clicking one of the two radio buttons:

MD5

or

SHA

.

In the Authentication Password field, type the password to use for authentication.

Indicate the type of encryption you want to use by clicking one of these three radio buttons:

DES

,

3DES

, or

AES

.

If you chose AES encryption, then from the AES Size drop-down list, choose the level of AES encryption to use:

128

,

192

, or

256

.

In the Encryption Password field, type the password to use for encryption. The maximum number of characters allowed for this password is 64.

Click

OK

to create a group (if this is the first user in that group), display this group in the Group Name drop-down list, and create a user for that group.

The Add SNMP User Entry dialog box closes.

The SNMPv3 Users pane lists the following information: SNMP Version 3 server group name, name of the user that belongs to the specified group, encrypted password setting, authentication setting, encryption algorithm setting, and the AES size setting.

Click

Apply

.

SNMP parameters for Version 3 are configured, and the changes are saved to the running configuration.

What to Do Next

See the

“Monitoring SNMP” section on page 73-10 .

Monitoring SNMP

NMSs are the PCs or workstations that you set up to monitor SNMP events and manage devices, such as the adaptive security appliance.You can monitor the health of a device from an NMS by polling required information from the SNMP agent that has been set up on the device. Predefined events from the SNMP agent to the NMS generate syslog messages. This section includes the following topics:

•

SNMP Syslog Messaging, page 73-11

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Monitoring SNMP

•

SNMP Monitoring, page 73-11

SNMP Syslog Messaging

SNMP generates detailed syslog messages numbered 212

nnn

. Syslog messages indicate the status of

SNMP requests, SNMP traps, SNMP channels, and SNMP responses from the adaptive security appliance to a specified host on a specified interface.

For detailed information about syslog messages, see


.

SNMP Monitoring

To monitor SNMP, perform the following steps:

Path


Type

show running-config snmp-server

, then click

Send

.


Type

show running-config snmp-server group

, then click

Send

.


Type

show running-config snmp-server host

, then click

Send

.


Type

show running-config snmp-server user

, then click

Send

.


Type

show snmp-server engineid

, then click

Send

.


Type

show snmp-server group

, then click

Send

.

Purpose

Displays all SNMP server configuration information.

Displays SNMP group configuration settings.

Displays configuration settings used by SNMP to control messages and notifications sent to remote hosts.

Displays SNMP user-based configuration settings.

Displays the ID of the SNMP engine configured.

Displays the names of configured SNMP groups.

Note

If the community string has already been configured, two extra groups appear by default in the output. This behavior is normal.

Displays the configured characteristics of the SNMP server.


Type

show snmp-server statistics

, then click

Send

.


Type

show snmp-server user

, then click

Send

.

Displays the configured characteristics of users.

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For additional information related to implementing SNMP, see the following sections:

•

RFCs for SNMP Version 3, page 73-12

•

•

MIBs, page 73-12

Application Services and Third-Party Tools, page 73-14

RFCs for SNMP Version 3

RFC

3410

3411

3412

3413

3414

3826

MIBs

Title

Introduction and Applicability Statements for Internet Standard Management Framework

An Architecture for Describing SNMP Management Frameworks

Message Processing and Dispatching for the Simple Network Management Protocol (SNMP)

Simple Network Management Protocol (SNMP) Applications

User-based Security Model (USM) for Version 3 of the Simple Network Management Protocol (SNMP)

The Advanced Encryption Standard (AES) Cipher Algorithm in the SNMP User-based Security Model

For a list of supported MIBs and traps for the adaptive security appliance by release, see the following

URL: http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml

To obtain a list of the supported SNMP MIBs for a specific adaptive security appliance, choose

Tools >

Command Line Interface

, type the following command, then click

Send

: hostname(config)#

show snmp-server oidlist

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Note

Although the

oidlist

keyword does not appear in the options list for the

show snmp-server

command help, it is available.

The following is sample output from the

show snmp-server oidlist

command:

[0] 1.3.6.1.2.1.1.1. sysDescr

[1] 1.3.6.1.2.1.1.2. sysObjectID

[2] 1.3.6.1.2.1.1.3. sysUpTime

[3] 1.3.6.1.2.1.1.4. sysContact

[4] 1.3.6.1.2.1.1.5. sysName

[5] 1.3.6.1.2.1.1.6. sysLocation

[6] 1.3.6.1.2.1.1.7. sysServices

[7] 1.3.6.1.2.1.2.1. ifNumber


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[8] 1.3.6.1.2.1.2.2.1.1. ifIndex

[9] 1.3.6.1.2.1.2.2.1.2. ifDescr

[10] 1.3.6.1.2.1.2.2.1.3. ifType

[11] 1.3.6.1.2.1.2.2.1.4. ifMtu

[12] 1.3.6.1.2.1.2.2.1.5. ifSpeed

[13] 1.3.6.1.2.1.2.2.1.6. ifPhysAddress

[14] 1.3.6.1.2.1.2.2.1.7. ifAdminStatus

[15] 1.3.6.1.2.1.2.2.1.8. ifOperStatus

[16] 1.3.6.1.2.1.2.2.1.9. ifLastChange

[17] 1.3.6.1.2.1.2.2.1.10. ifInOctets

[18] 1.3.6.1.2.1.2.2.1.11. ifInUcastPkts

[19] 1.3.6.1.2.1.2.2.1.12. ifInNUcastPkts

[20] 1.3.6.1.2.1.2.2.1.13. ifInDiscards

[21] 1.3.6.1.2.1.2.2.1.14. ifInErrors

[22] 1.3.6.1.2.1.2.2.1.16. ifOutOctets

[23] 1.3.6.1.2.1.2.2.1.17. ifOutUcastPkts

[24] 1.3.6.1.2.1.2.2.1.18. ifOutNUcastPkts

[25] 1.3.6.1.2.1.2.2.1.19. ifOutDiscards

[26] 1.3.6.1.2.1.2.2.1.20. ifOutErrors

[27] 1.3.6.1.2.1.2.2.1.21. ifOutQLen

[28] 1.3.6.1.2.1.2.2.1.22. ifSpecific

[29] 1.3.6.1.2.1.4.1. ipForwarding

[30] 1.3.6.1.2.1.4.20.1.1. ipAdEntAddr

[31] 1.3.6.1.2.1.4.20.1.2. ipAdEntIfIndex

[32] 1.3.6.1.2.1.4.20.1.3. ipAdEntNetMask

[33] 1.3.6.1.2.1.4.20.1.4. ipAdEntBcastAddr

[34] 1.3.6.1.2.1.4.20.1.5. ipAdEntReasmMaxSize

[35] 1.3.6.1.2.1.11.1. snmpInPkts

[36] 1.3.6.1.2.1.11.2. snmpOutPkts

[37] 1.3.6.1.2.1.11.3. snmpInBadVersions

[38] 1.3.6.1.2.1.11.4. snmpInBadCommunityNames

[39] 1.3.6.1.2.1.11.5. snmpInBadCommunityUses

[40] 1.3.6.1.2.1.11.6. snmpInASNParseErrs

[41] 1.3.6.1.2.1.11.8. snmpInTooBigs

[42] 1.3.6.1.2.1.11.9. snmpInNoSuchNames

[43] 1.3.6.1.2.1.11.10. snmpInBadValues

[44] 1.3.6.1.2.1.11.11. snmpInReadOnlys

[45] 1.3.6.1.2.1.11.12. snmpInGenErrs

[46] 1.3.6.1.2.1.11.13. snmpInTotalReqVars

[47] 1.3.6.1.2.1.11.14. snmpInTotalSetVars

[48] 1.3.6.1.2.1.11.15. snmpInGetRequests

[49] 1.3.6.1.2.1.11.16. snmpInGetNexts

[50] 1.3.6.1.2.1.11.17. snmpInSetRequests

[51] 1.3.6.1.2.1.11.18. snmpInGetResponses

[52] 1.3.6.1.2.1.11.19. snmpInTraps

[53] 1.3.6.1.2.1.11.20. snmpOutTooBigs

[54] 1.3.6.1.2.1.11.21. snmpOutNoSuchNames

[55] 1.3.6.1.2.1.11.22. snmpOutBadValues

[56] 1.3.6.1.2.1.11.24. snmpOutGenErrs

[57] 1.3.6.1.2.1.11.25. snmpOutGetRequests

[58] 1.3.6.1.2.1.11.26. snmpOutGetNexts

[59] 1.3.6.1.2.1.11.27. snmpOutSetRequests

[60] 1.3.6.1.2.1.11.28. snmpOutGetResponses

[61] 1.3.6.1.2.1.11.29. snmpOutTraps

[62] 1.3.6.1.2.1.11.30. snmpEnableAuthenTraps

[63] 1.3.6.1.2.1.11.31. snmpSilentDrops

[64] 1.3.6.1.2.1.11.32. snmpProxyDrops

[65] 1.3.6.1.2.1.31.1.1.1.1. ifName

[66] 1.3.6.1.2.1.31.1.1.1.2. ifInMulticastPkts

[67] 1.3.6.1.2.1.31.1.1.1.3. ifInBroadcastPkts

[68] 1.3.6.1.2.1.31.1.1.1.4. ifOutMulticastPkts

[69] 1.3.6.1.2.1.31.1.1.1.5. ifOutBroadcastPkts

[70] 1.3.6.1.2.1.31.1.1.1.6. ifHCInOctets

--More--



OL-20339-01 73-13


Feature History for SNMP

Application Services and Third-Party Tools

For information about SNMP support, see the following URL: l http://www.cisco.com/en/US/tech/tk648/tk362/tk605/tsd_technology_support_sub-protocol_home.htm

For information about using third-party tools to walk SNMP Version 3 MIBs, see the following URL: http://www.cisco.com/en/US/docs/security/asa/asa83/snmp/snmpv3_tools.html

Feature History for SNMP



Table 73-2

Feature Name

SNMP Versions 1 and 2c

SNMP Version 3

Feature History for SNMP

Platform

Releases

7.0(1)

Password encryption

8.2(1)

8.3(1)


Provides adaptive security appliance network monitoring and event information by transmitting data between the SNMP server and SNMP agent through the clear text community string.



.

Provides 3DES or AES encryption and support for SNMP Version 3, the most secure form of the supported security models. This version allows you to configure users, groups, and hosts, as well as authentication characteristics by using the USM. In addition, this version allows access control to the agent and MIB objects, and includes additional MIB support.

The following screen was modified:


.

Supports password encryption.

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C H A P T E R

74

Configuring Smart Call Home

This chapter describes how to configure the Smart Call Home feature, and includes the following sections:

•

Information About Smart Call Home, page 74-1

•

•

•

•

•


Licensing Requirements for Smart Call Home, page 74-2

Configuring Smart Call Home, page 74-2

Smart Call Home Monitoring, page 74-5

Feature History for Smart Call Home, page 74-6

Information About Smart Call Home

Smart Call Home offers proactive diagnostics and real-time alerts on the adaptive security appliance and provides higher network availability and increased operational efficiency. This feature provides higher network availability through proactive and quick issue resolution by doing the following:

•

Identifying issues quickly with continuous monitoring, real-time, proactive alerts, and detailed diagnostics.

•

•

Making you aware of potential problems through Smart Call Home notifications, in which a service request has been opened, with all diagnostic data attached.

Resolving critical problems faster with direct, automatic access to experts in Cisco TAC.

Smart Call Home offers increased operational efficiency by providing you with the ability to do the following:

•

Use staff resources more efficiently by reducing troubleshooting time.

•

Generate service requests to Cisco TAC automatically, routed to the appropriate support team, which provides detailed diagnostic information that speeds problem resolution.

Smart Call Home offers quick, web-based access to required information that provides you with the ability to do the following:

•

•

•

Review all Smart Call Home messages, diagnostics, and recommendations in one place.

Check service request status quickly.

View the most up-to-date inventory and configuration information for all Smart Call Home-enabled devices.

OL-20339-01


74-1

Chapter 74 Configuring Smart Call Home









IPv6 Guidelines

Supports IPv6.


In multiple context mode, the

snapshots

command is divided into two commands: one to obtain information from the system context and one to obtain information from the normal context.

Licensing Requirements for Smart Call Home


Model

All models


Base License.

Configuring Smart Call Home You must configure Smart Call Home to obtain proactive diagnostics and real-time alerts for your adaptive security appliance.

Detailed Steps

Step 1

Step 2

Step 3

To configure Smart Call Home service, system setup, and alert subscription profiles, choose

Configuration> Device Management> Smart Call Home

.

Check the

Enable Smart Call Home

check box to enable the feature.

Double-click

System Setup

. The System Setup consists of three panes. Each pane can be expanded or collapsed by double-clicking the title row. In the Mail Servers pane. you can set up mail servers through which Smart Call Home messages are delivered to e-mail subscribers. In the Contact Information pane, you can enter the information of the person to contact for the adaptive security appliance that appears in

Smart Call Home messages. This pane includes the following:

•

•

•

•

•

•

The name of the contact person.

The contact phone number.

The postal address of the contact person.

The e-mail address of the contact.

The “from” e-mail address in Smart Call Home e-mail.

The “reply-to” e-mail address in Smart Call Home e-mail.

74-2


OL-20339-01



Step 4

Step 5

•

•

•

•

•

•

The customer ID.

The site ID.

The contract ID.

•

In the Alert Control pane, administrators can fine tune alert control parameters. This pane includes the

Alert group status pane, which lists the status (enabled or disabled) of the following alert groups:

•

The diagnostics alert group.

•

The configuration alert group.

The environmental alert group.

The inventory alert group.

The snapshot alert group.

•

•

•

The syslog alert group.

The telemetry alert group.

The threat alert group.

The maximum number of Smart Call Home messages processed per minute.

•

The “from” e-mail address in Smart Call Home e-mail.

Double-click

Alert Subscription Profiles

. Each named subscription profile identifies subscribers and alert groups of interest.

a.

b.

Click

Add

or

Edit

to display the Subscription Profile Editor, in which you can create a new subscription profile or edit an existing subscription profile.

Click

Delete

to remove the selected profile.

c.

Check the

Active

check box to send the Smart Call Home message of the selected subscription profile to subscribers.

When you click

Add

or

Edit

, the Add or Edit Alert Subscription Profile dialog box appears.

a.

b.

c.

d.

The Name field is read-only, so you cannot edit it.

Check the

Enable this subscription profile

check box to enable or disable this particular profile.

Click either the

HTTP

or

Email

radio button in the Alert Delivery Method area.

In the Subscribers field, specify the alert delivery method: e-mail address or web address.

Step 6

subscriber, including the preferred message format and the maximum message size.

For time-based alerts, in the Alert Dispatch area, click

Add

or

Edit

to display the Add or Edit

Configuration Alert Dispatch Condition dialog box.

a.

•

In the Alert Dispatch Frequency area, specify the frequency in which to send the information to subscribers:

For monthly subscription, specify the day of the month, as well as the time of the day to send the information. If they are not specified, the adaptive security appliance chooses appropriate values for them.

•

•

For weekly subscription, specify the day of the week, as well as the time of the day to send the information. If they are not specified, the adaptive security appliance chooses appropriate values for them.

For daily subscription, specify the time of the day to send the information. If it is not specified, the adaptive security appliance chooses an appropriate value for it.

OL-20339-01


74-3



Step 7

Step 8

Step 9

Step 10

Step 11

Step 12

Step 13

• b.

For hourly subscription, specify the minute of the hour to send the information. If it is not specified, the adaptive security appliance chooses an appropriate value for it. Hourly subscription is only applicable to the snapshot and telemetry alert groups.

Click the

Basic

or

Detailed

radio button to provide the desired level of information to subscribers.

Click

OK

when you are done.

c.

For diagnostic, environment, and threat event-based alerts, in the Alert Dispatch area, click

Add

or

Edit

to display the Create or Edit Diagnostic Alert Dispatch Condition dialog box.

Specify the event severity that triggers dispatch of the alert to subscribers in the Event Severity drop-down list, and then click

OK

.

For inventory time-based alerts, in the Alert Dispatch area, click

Add

or

Edit

to display the Create or

Edit Inventory Alert Dispatch Condition dialog box.

Specify how often to dispatch alerts to subscribers in the Alert Dispatch Frequency drop-down list, and then click

OK

.

For snapshot time-based alerts, in the Alert Dispatch area, click

Add

or

Edit


Edit Snapshot Alert Dispatch Condition dialog box.

a.


–

–



–

–



b.

For syslog event-based alerts, in the Alert Dispatch area, click

Add

or

Edit

to display the Create or Edit

Syslog Alert Dispatch Condition dialog box.

a.

Check the

Specify the event severity which triggers the dispatch of alert to subscribers check box

, and choose the event severity from the drop-down list.

b.

–

For interval subscription, specify how often, in minutes, the formation is sent to the subscribers.

This requirement is only applicable to the snapshot alert group.

Click

OK

when you are done.

c.

Check the

Specify the message IDs of syslogs which trigger the dispatch of alert to subscribers

check box.

Specify the syslog message IDs that trigger dispatch of the alert to subscribers according to the on-screen instructions.

d.

Click

OK

when you are done.

For telemetry event-based alerts, in the Alert Dispatch area, click

Add

or

Edit


Edit Telemetry Alert Dispatch Condition dialog box.

a.


74-4


OL-20339-01


Smart Call Home Monitoring b.

–

–

–




–


Click

OK

when you are done.

Smart Call Home Monitoring

To monitor the Smart Call Home feature, perform the following steps:

Path


Type

show call- home detail

, then click

Send

.


Type

show call-home mail-server status

, then click

Send

.


Purpose

Shows the current Smart Call Home detail configuration.

Shows the current mail server status.

Shows the configuration of Smart Call Home profiles.

Type

show smart-call- home profile {

profile name

| all

, then click

Send

.


Shows the registered module status.

Type

show call-home registered-module all

, then click

Send

.


Type

show smart-call statistics

, then click

Send

.


Shows call-home detail status.

Shows the current Smart Call Home configuration.

Type

show call-home

, then click

Send

.


Type

show dynamic-filter reports top

, then click

Send

.


Type

show dynamic-filter statistics

, then click

Send

.


Type

show running-config call-home

, then click

Send

.

Generates reports of the top ten botnet sites, ports, and infected hosts.

Shows how many connections were monitored with the Botnet

Traffic Filter, and how many of those connections match the whitelist, blacklist, and graylist.

Shows the current Smart Call Home running configuration.

OL-20339-01


74-5


Feature History for Smart Call Home

Path


Type

show shun

, then click

Send

.


Type

show smart-call- home alert-group

, then click

Send

.


Type

show threat-detection rate

, then click

Send

.


Type

show threat-detection rate

, then click

Send

.


Type

show threat-detection shun

, then click

Send

.


Type

show threat-detection statistics

, then click

Send

.

Purpose

Shows shun information.

Shows the current status of Smart Call Home alert groups.

Shows basic threat detection statistics.

Show current attackers and targets.

Shows currently shunned hosts.

Shows statistics for hosts, ports, and protocols.

Feature History for Smart Call Home

Table 1 lists each feature change and the platform release in which it was implemented.


Table 1

Feature Name

Smart Call Home

Feature History for Smart Call Home

Platform

Releases

8.2(2)


The Smart Call Home feature offers proactive diagnostics and real-time alerts on the adaptive security appliance, and provides higher network availability and increased operational efficiency.


Configuration> Device Management> Smart Call Home

74-6


OL-20339-01

P

A R T

1 6

System Administration

C H A P T E R

75

Managing Software and Configurations

This chapter describes how to manage the adaptive security appliance software and configurations and includes the following sections:

•

Managing Files, page 75-1

•

•

•

•

•

Configuring Auto Update, page 75-7

Configuring the Boot Image/Configuration Settings, page 75-9

Upgrading Software from Your Local Computer, page 75-10

Upgrading Software from the Cisco.com Wizard, page 75-11

•

•

Scheduling a System Restart, page 75-12

Backing Up and Restoring Configurations, Images, and Profiles, page 75-13

Downgrading Your Software, page 75-19

Managing Files

ASDM provides a set of file management tools to help you perform basic file management tasks. The

File Management tool lets you view, move, copy, and delete files stored in flash memory, transfer files, and to manage files on remote storage devices (mount points).

Note

In multiple context mode, this tool is only available in the system security context.


•

Accessing the File Management Tool, page 75-1

•

•

Managing Mount Points, page 75-2

Transferring Files, page 75-5

Accessing the File Management Tool

To use the file management tools, perform the following steps:

Step 1


Tools > File Management

.

The File Management dialog box appears.


OL-20339-01 75-1

Chapter 75 Managing Software and Configurations

Managing Files

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

•

•

•

The Folders pane displays the available folders on disk.

Flash Space shows the total amount of flash memory and how much memory is available.

The Files area displays the following information about files in the selected folder:

–

–

Path

Filename

–

–

Size (bytes)

Time Modified

–

Status, which indicates whether a selected file is designated as a boot configuration file, boot image file, ASDM image file, SVC image file, CSD image file, or APCF image file.

Click

View

to display the selected file in your browser.

Click

Cut

to cut the selected file for pasting to another directory.

Click

Copy

to copy the selected file for pasting to another directory.

Click

Paste

to paste the copied file to the selected destination.

Click

Delete

to remove the selected file from flash memory.

Click

Rename

to rename a file.

Click

New Directory

to create a new directory for storing files.

Click

File Transfer

to open the File Transfer dialog box. See the

“Transferring Files” section on page 75-5


Click

Mount Points

to open the Manage Mount Points dialog box. See the

“Managing Mount Points” section on page 75-2 for more information.

Managing Mount Points

This feature lets you configure remote storage (mount points) for network file systems using a CIFS or

FTP connection. The dialog box lists the mount-point name, connection type, server name or IP address, and the enabled setting (yes or no). You can add, edit, or delete mount points. See the

“Adding or Editing a CIFS/FTP Mount Point” section on page 75-3 for more information. You can access a CIFS mount

point after it has been created. For more information, see

Accessing a CIFS Mount Point, page 75-4 .

Note

On a PIX 535 security appliance in single, routed mode, the Managing Mount Point feature is not available.


•

Adding or Editing a CIFS/FTP Mount Point, page 75-3

•

Accessing a CIFS Mount Point, page 75-4

75-2


OL-20339-01


Managing Files

Adding or Editing a CIFS/FTP Mount Point

To add a CIFS mount point, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Click

Add

, and then choose

CIFS Mount Point

.

The Add CIFS Mount Point dialog box appears.

The Enable mount point check box is automatically checked, which is the default setting.

Enter the mount-point name, server name or IP address, and share name in the applicable fields.

In the Authentication section, enter the NT domain, username and password, and then confirm the password.

Click

OK

.

To add an FTP mount point, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Click

Add

, and then choose

FTP Mount Point

.

The Add FTP Mount Point dialog box appears.

The Enable mount point check box is automatically checked, which is the default setting.

Enter the mount-point name and the server name or IP address in the applicable fields.

In the FTP Mount Options area, click the

Active Mode

or

Passive Mode

option.

Enter the path to mount the remote storage.

In the Authentication area, enter the NT domain, username and password, and then confirm the password.

Click

OK

.

To edit a CIFS mount point, perform the following steps:

Step 1

Choose the CIFS mount-point you want to modify, and click

Edit

.

The Edit CIFS Mount Point dialog box appears.

Note

You cannot change the CIFS mount-point name.

Step 2

Make the changes to the remaining settings, and click

OK

when you are done.

To edit an FTP mount point, perform the following steps:

Step 1

Choose the FTP mount-point you want to modify, and click

Edit

.

The Edit FTP Mount Point dialog box appears.

OL-20339-01


75-3


Managing Files

Step 2

Note

You cannot change the FTP mount-point name.

Make the changes to the remaining settings, and click

OK

when you are done.

Accessing a CIFS Mount Point

To access a CIFS mount point after it has been created, perform the following steps:

Step 1

Step 2

Step 3

Start the adaptive security appliance CLI.

Create the mount by entering the

mount

name of mount

type cifs

command.

Enter the

show run mount

command.

The following output appears:

Note

In this example, win2003 is the name of the mount.

Step 4

Step 5

server kmmwin2003 share sharefolder username webvpnuser2 password ******** status enable

Enter the

dir

command to list all enabled mounts as subdirectories, which is similar to mounting a drive on the Windows PC. For example, in the following output, FTP2003:, FTPLINUX:, and win2K: are configured mounts.


dir

command:

FTP2003: Directory or file name

FTPLINUX: Directory or file name

WIN2003: Directory or file name all-filesystems List files on all filesystems disk0: Directory or file name disk1: Directory or file name flash: Directory or file name system: Directory or file name win2K: Directory or file name

Enter the

dir

command for that mount (for example,

dir WIN2003

), and copy files to and from flash

(disk0:) to any of the listed mounts.


dir WIN2003

command.

Directory of WIN2003:/

---- 14920928 08:33:36 Apr 03 2009 1_5_0_01-windows-i586-p.exe

---- 33 11:27:16 Jun 07 2007 AArenameIE70

---- 28213021 15:15:22 Apr 03 2009 atest2(3).bin

---- 61946730 12:09:40 Mar 17 2009 atest2.bin

---- 5398366 14:52:10 Jul 28 2008 atest222.bin

---- 2587728 10:07:44 Dec 06 2005 cCITRIXICA32t.exe

---- 1499578 15:26:50 Dec 02 2005 ccore.exe

---- 61946728 11:40:36 Dec 09 2005 CIFSTESTT.bin

---- 2828 13:46:04 May 11 2009 ClientCert.pfx

d--- 16384 14:48:28 Mar 20 2007 cookiefolder

75-4


OL-20339-01


---- 4399 15:58:46 Jan 06 2006 Cookies.plist

---- 2781710 12:35:00 Dec 12 2006 coreftplite1.3.exe

---- 0 10:22:52 Jul 13 2007 coreftplite1.3.exe.download

---- 245760 15:13:38 Dec 21 2005 Dbgview.exe

---- 1408249 11:01:34 Dec 08 2005 expect-5.21r1b1-setup.exe

d--- 16384 14:49:14 Jul 28 2008 folder157

---- 101 09:33:48 Dec 12 2005 FxSasser.log

---- 2307104 09:54:12 Dec 12 2005 ica32t.exe

---- 8732552 10:14:32 Apr 29 2009 iclientSetup_IFen_flex51.exe

d--- 16384 08:32:46 Apr 03 2009 IE8withVistaTitan

---- 15955208 08:34:18 Aug 14 2007 j2re.exe

---- 16781620 13:38:22 Jul 23 2008 jre-1_5_0_06-windows-i586-p.exe

<--- More --->

Managing Files

Transferring Files

The File Transfer tool lets you transfer files from either a local or remote location. You can transfer a local file on your computer or a flash file system to and from the adaptive security appliance. You can transfer a remote file to and from the adaptive security appliance using HTTP, HTTPS, TFTP, FTP, or

SMB.

To transfer files between your local computer and a flash file system, perform the following steps:

Step 1

Step 2

Step 3

Step 4



.


Click the down arrow next to

File Transfer

, and then click

Between Local PC and Flash

.

The File Transfer dialog box appears.

Select and

drag

the file(s) from either your local computer or the flash file system that you want to upload or download to the desired location. Alternatively, select the file(s) from either your local computer or the flash file system that you want to upload or download, and click the right arrow or left arrow to transfer the file(s) to the desired location.

Click

Close

when you are done.

To transfer files between a remote server and a flash file system, perform the following steps:

Step 1

Step 2

Step 3

Step 4



.


Click the down arrow from the File Transfer drop-down list, and then click

Between Remote Server and Flash

.

The File Transfer dialog box appears.

To transfer a file from a remote server, click the

Remote server

option.

Define the source file to be transferred.

a.

Choose the path to the location of the file, including the IP address of the server.

OL-20339-01


75-5


Managing Files

Note

File transfer supports IPv4 and IPv6 addresses.

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Step 12

Step 13 b.

Enter the type (if the path is FTP) or the port number (if the path is HTTP or HTTPS) of the remote server. Valid FTP types are the following:

–

ap—ASCII files in passive mode

–

–

an—ASCII files in non-passive mode ip—Binary image files in passive mode

–

in—Binary image files in non-passive mode

To transfer the file from the flash file system, click the

Flash file system

option.

Enter the path to the location of the file or click

Browse Flash

to find the file location.

In addition, you can copy a file from your startup configuration, running configuration, or an SMB file system through the CLI. For instructions about using the

copy

command, see the



.

Define the destination of the file to be transferred.

a.

To transfer the file to the flash file system, choose the

Flash file system

option.

b.

Enter the path to the location of the file or click

Browse Flash

to find the file location.

To transfer a file to a remote server, choose the

Remote server

option.

a.

Enter the path to the location of the file.

b.

For FTP transfers, enter the type. Valid types are the following:

–

–

ap—ASCII files in passive mode an—ASCII files in non-passive mode

–

–

ip—Binary image files in passive mode in—Binary image files in non-passive mode

Click

Transfer

to start the file transfer.

The Enter Username and Password dialog box appears.

Enter the username, password, and domain (if required) for the remote server.

Click

OK

to continue the file transfer.

The file transfer process might take a few minutes; make sure that you wait until it is finished.

Click

Close

when the file transfer is finished.

•

Saving the Running Configuration to a TFTP Server, page 75-6

Saving the Running Configuration to a TFTP Server

This feature stores a copy of the current running configuration file on a TFTP server.

To save the running configuration to a TFTP server, perform the following steps:

Step 1


File > Save Running Configuration to TFTP Server

.

75-6


OL-20339-01


Configuring Auto Update

Step 2

The Save Running Configuration to TFTP Server dialog box appears.

Enter the TFTP server IP address and file path on the TFTP server in which the configuration file will be saved, and then click

Save Configuration

.

Note

To configure default TFTP settings, choose

Configuration > Device Management >

Management Access > File Access > TFTP Client

. After you have configured this setting, the

TFTP server IP address and file path on the TFTP server appear automatically in this dialog box.



•

•

Setting the Polling Schedule, page 75-8

Adding or Editing an Auto Update Server, page 75-9

The Auto Update pane lets you configure the adaptive security appliance to be managed remotely from servers that support the Auto Update specification. Auto Update lets you apply configuration changes to the adaptive security appliance and receive software updates from remote locations.

Auto Update is useful in solving many issues facing administrators for adaptive security appliance management, such as:

•

•

•

Overcoming dynamic addressing and NAT challenges.

Commiting configuration changes in one action.

•

•

Providing a reliable method for updating software.

Leveraging well-understood methods for high availability (failover).

Providing flexibility with an open interface.

•

Simplifying security solutions for Service Provider environments.

The Auto Update specification provides the infrastructure necessary for remote management applications to download adaptive security appliance configurations, software images, and to perform basic monitoring from a centralized location or multiple locations.

The Auto Update specification allows the Auto Update server to either push configuration information and send requests for information to the adaptive security appliance, or to pull configuration information by having the adaptive security appliance periodically poll the Auto Update server. The Auto Update server can also send a command to the adaptive security appliance to send an immediate polling request at any time. Communication between the Auto Update server and the adaptive security appliance requires a communications path and local CLI configuration on each adaptive security appliance.

Important Notes

•

If the adaptive security appliance configuration is updated from an Auto Update server, ASDM is not notified. You must choose

Refresh

or

File > Refresh ASDM with the Running Configuration on the Device

to obtain the latest configuration, and any changes to the configuration made in

ASDM will be lost.

•

If HTTPS is chosen as the protocol to communicate with the Auto Update server, the adaptive security appliance uses SSL, which requires the adaptive security appliance to have a DES or 3DES license.


OL-20339-01 75-7



To configure the Auto Update feature, choose

Configuration > Devuice Management > System

Image/Configuration > Auto Update

. The Auto Update pane consists of an Auto Update Servers table and two areas: the Timeout area and the Polling area.

The Auto Update Servers table lets you view the parameters of previously configured Auto Update servers. The adaptive security appliance polls the server listed at the top of the table first. To change the order of the servers in the table, click

Move Up

or

Move Down

. The Auto Update Servers table includes the following columns:

•

Server—The name or IP address of the Auto Update server.

•

•

User Name—The user name used to access the Auto Update server.

Interface—The interface used when sending requests to the Auto Update server.

•

Verify Certificate—Indicates whether the adaptive security appliance checks the certificate returned by the Auto Update server with the CA root certificates. The Auto Update server and the adaptive security appliance must use the same CA.

Double-clicking any of the rows in the Auto Update Server table opens the Edit Auto Update Server dialog box, in which you can modify the Auto Update server parameters. These changes are immediately reflected in the table, but you must click

Apply

to save them to the configuration.

The Timeout area lets you set the amount of time the adaptive security appliance waits for the Auto

Update server to time out. The Timeout area includes the following fields:

•

Enable Timeout Period—Check to enable the adaptive security appliance to time out if no response is received from the Auto Update server.

•

Timeout Period (Minutes)—Enter the number of minutes the adaptive security appliance will wait to time out if no response is received from the Auto Update server.

The Polling area lets you configure how often the adaptive security appliance will poll for information from the Auto Update server. The Polling area includes the following fields:

•

•

•

Polling Period (minutes)—The number of minutes the adaptive security appliance will wait to poll the Auto Update server for new information.

Poll on Specified Days—Allows you to specify a polling schedule.

•

Set Polling Schedule—Displays the Set Polling Schedule dialog box where you can configure the days and time-of-day to poll the Auto Update server.

Retry Period (minutes)—The number of minutes the adaptive security appliance will wait to poll the

Auto Update server for new information if the attempt to poll the server fails.

•

Retry Count—The number of times the adaptive security appliance will attempt to retry to poll the

Auto Update server for new information.

Setting the Polling Schedule

The Set Polling Schedule dialog box lets you configure specific days and the time-of-day for the adaptive security appliance to poll the Auto Update server.

The Set Polling Schedule dialog box includes the following fields:

Days of the Week—Check the days of the week that you want the adaptive security appliance to poll the

Auto Update server.

The Daily Update pane group lets you configure the time of day when you want the adaptive security appliance to poll the Auto Update server, and includes the following fields:

•

Start Time—Enter the hour and minute to begin the Auto Update poll.


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Configuring the Boot Image/Configuration Settings

•

Enable randomization—Check to enable the adaptive security appliance to randomly choose a time to poll the Auto Update server.

Adding or Editing an Auto Update Server

The Add/Edit Auto Update Server dialog box includes the following fields:

•

URL—The protocol that the Auto Update server uses to communicate with the adaptive security appliance, either HTTP or HTTPS, and the path to the Auto Update server.

•

•

Interface—The interface to use when sending requests to the Auto Update server.

Verify Certificate—Click to enable the adaptive security appliance to verify the certificate returned by the Auto Update server with the CA root certificates. The Auto Update server and the adaptive security appliance must use the same CA.

The User area includes the following fields:

•

User Name (Optional)—Enter the user name needed to access the Auto Update server.

•

•

•

Password—Enter the user password for the Auto Update server.

Confirm Password—Reenter the user password for the Auto Update server.

•

Use Device ID to uniquely identify the ASA—Enables authentication using a device ID. The device

ID is used to uniquely identify the adaptive security appliance to the Auto Update server.

Device ID—Type of device ID to use.

–

–

–

–

–

Hostname—The name of the host.

Serial Number—The device serial number.

IP Address on interface—The IP address of the selected interface, used to uniquely identify the adaptive security appliance to the Auto Update server.

MAC Address on interface—The MAC address of the selected interface, used to uniquely identify the adaptive security appliance to the Auto Update server.

User-defined value—A unique user ID.

Configuring the Boot Image/Configuration Settings

The Boot Image/Configuration pane lets you choose which image file the adaptive security appliance will boot from, as well as the configuration file to use at startup. Choose


Management > System Image/Configuration > Boot Image/Configuration

.

You can specify up to four local binary image files for use as the startup image, and one image located on a TFTP server for the device to boot from. If you specify an image located on a TFTP server, it must be first in the list. If the device cannot reach the TFTP server to load the image, it tries to load the next image file in the list located in flash.

If you do not specify any boot variable, the first valid image on internal flash will be chosen to boot the system. The Boot Image/Configuration pane includes the following fields:

•

Boot Order—Displays the order in which binary image files will be used to boot.

•

•

Boot Image Location—Displays the physical location and path of the boot file.

Boot Configuration File Path—Displays the location of the configuration file.

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Upgrading Software from Your Local Computer

•

•

•

•

•

•

•

Add—Lets you add a flash or TFTP boot image entry to be used in the boot process. For more information, see the

“Adding a Boot Image” section on page 75-10

.

Edit—Lets you edit a flash or TFTP boot image entry.

Delete—Deletes the selected flash or TFTP boot image entry.

Move Up—Moves the selected flash or TFTP boot image entry up in the boot order.

Move Down—Moves the selected flash or TFTP boot image entry down in the boot order.

Browse Flash—Lets you specify the location of a boot image or configuration file.

ASDM Image File Path—Displays the location of the configuration file to use at startup.

Adding a Boot Image

To add a boot image entry to the boot order list, click

Add

in the Boot Image/Configuration pane.

You can select a flash or TFTP image to add a boot image to the boot order list.

Either type the path of the image, or click

Browse Flash

to specify the image location. You must type the path of the image location if you are using TFTP.

•

Flash Image—Select to add a boot image located in the flash file system.

•

–

Path—Specify the path of the boot image in the flash file system.

TFTP Image—Select to add a boot image located on a TFTP server.

•

•

•

– [

Path

]

—Enter the path of the boot image file on the TFTP server, including the IP address of the server.

OK—Accepts changes and returns to the previous pane.

Cancel—Discards changes and returns to the previous pane.

Help—Provides more information.

Upgrading Software from Your Local Computer

The Upgrade Software from Local Computer tool lets you upload an image file from your PC to the flash file system to upgrade the adaptive security appliance.

To upgrade software from your PC, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5


Tools > Upgrade Software from Local Computer

.

The Upgrade Software from Local Computer dialog box appears.

Choose the image file to upload from the drop-down list.

Enter the local path to the file on your PC or click


to find the file on your PC.

Enter the path to the flash file system or click

Browse Flash

to find the directory or file in the flash file system.

Click

Image to Upload

. The uploading process might take a few minutes; make sure you wait until it is finished.

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Upgrading Software from the Cisco.com Wizard

Upgrading Software from the Cisco.com Wizard

The Upgrade Software from Cisco.com Wizard lets you automatically upgrade the ASDM and adaptive security appliance to more current versions.

Note

This feature is only available in single mode and in the system space of multiple security mode. It is not available in a user or admin context.

In this wizard, you can do the following:

•

•

•

Choose an ASA image file and/or ASDM image file to upgrade.

Review the upgrade changes that you have made.

Download the image or images and install them.

•

•

Review the status of the installation.

If the installation completed successfully, restart the adaptive security appliance to save the configuration and complete the upgrade.

To upgrade software from Cisco.com, perform the following steps:

Step 1

Step 2

Step 3

Step 4


Tools > Check for ASA/ASDM Updates

.

The Cisco.com Authentication dialog box appears.

Enter your assigned Cisco.com username and the Cisco.com password, and then click

Login

.

A Status dialog box appears, indicating that ASDM is loading the Upgrade Wizard. The Cisco.com

Upgrade Wizard appears. The Overview screen describes the steps in the image upgrade installation process.

Click

Next

to display the Select Software screen.

The current ASA version and ASDM version appear.

To upgrade the ASA version and ASDM version, perform the following steps:

a.

b.

In the ASA area, check the

Upgrade to

check box, and then choose an ASA version to which you want to upgrade from the drop-down list.

In the ASDM area, check the

Upgrade to

check box, and then choose an ASDM version to which you want to upgrade from the drop-down list.

Note

If the adaptive security appliance version list or the ASDM version list is empty, a statement appears informing you that no new adaptive security appliance or ASDM images are available and your device software is up-to-date. If you see this statement, you can exit the wizard.

Step 5

Step 6

Click

Next

to display the Review Changes screen.

Verify the following items:

•

•

•

The adaptive security appliance image file and/or ASDM image file that you have downloaded are the correct ones.

The adaptive security appliance image file and/or ASDM image file that you want to upload are the correct ones.

The correct adaptive security appliance boot image has been selected.

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Scheduling a System Restart

Step 7

Step 8

Step 9

Click

Next

to start the upgrade installation.

You can then view the status of the upgrade installation as it progresses.

The Results screen appears, which provides additional details, such as the upgrade installation status

(success or failure).

During the upgrade process from Version 8.2(1) to Version 8.3(1), the following files are automatically saved to flash memory:

•

The startup configuration

•

•

The per-context configuration

The bootup error log, which includes any migration messages

If there is insufficient memory to save the configuration files, an error message appears on the console of the adaptive security appliance and is saved in the bootup error log file. All previously saved configuration files are also removed.

If the upgrade installation succeeded, for the upgrade versions to take effect, check the

Save configuration and reload device now

check box to restart the adaptive security appliance, and restart

ASDM.

Click

Finish

to exit the wizard and save the configuration changes that you have made.

Note

To upgrade to the next higher version, if any, you must restart the wizard.

Scheduling a System Restart

The System Reload tool lets you schedule a system restart or cancel a pending restart.

To schedule a system restart, perform the following steps:

Step 1

Step 2


Tools > System Reload

.

In the Reload Scheduling area, define the following settings:

a.

b.

For the Configuration State, choose either to save or discard the running configuration at restart time.

For the Reload Start Time, choose from the following options:

–

–

Click

Now

to perform an immediate restart.

Click

Delay by

to delay the restart by a specified amount of time. Enter the time before the restart begins in hours and minutes or only minutes.

–

Click

Schedule at

to schedule the restart to occur at a specific time and date. Enter the time of day the restart is to occur, and select the date of the scheduled restart.

In the Reload Message field, enter a message to send to open instances of ASDM at restart time.

c.

d.

e.

Check the

On reload failure force immediate reload after

check box to show the amount of time elapsed in hours and minutes or only minutes before a restart is attempted again.

Click

Schedule Reload

to schedule the restart as configured.

The Reload Status area displays the status of the restart.

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Backing Up and Restoring Configurations, Images, and Profiles

Step 3


•

•

•

Click

Click

Refresh

to refresh the Reload Status display after a scheduled restart is finished.

Click

Cancel Reload

Details

to stop a scheduled restart.

to display the results of a scheduled restart.


The Backup and Restore features options on the Tools menu let you back up and restore the adaptive security appliance running configuration, startup configuration, installed add-on images, and SSL VPN

Client images and profiles.

The Backup Configurations screen on the ASDM lets you choose the file types to back up, compresses them into a single zip file, then transfer the zip file to the directory that you choose on your computer.

Similarly, to restore files, you choose the source zip file on your computer and then choose the file types to be restored.


•

Backing Up Configurations, page 75-13

•

Restoring Configurations, page 75-17

Backing Up Configurations

This procedure explains how to back up configurations and images to a .zip file and transfer it to your local computer.

Caution

If you have set a master passphrase for your ASA then you will need that master passphrase in order to restore the backup you create with this procedure. If you do not know the master passphrase for the ASA, see

Configuring the Master Passphrase, page 9-6

to learn how to reset it before continuing with the backup.

Step 1

Step 2

Create a folder on your computer to store backup files so they will be easy to find if you have to restore them later.

From the ASDM menu, select

Tools > Backup Configurations

.

The Backup Configurations dialog box opens. Click the down arrow in the

SSL VPN Configuration

area to view the backup options for SSL VPN configurations. By default, all configuration files are checked and will be backed up if they are available. If you want to back up all of the files in the list, go to Step

5 .

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Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 9

Step 10

Uncheck the

Backup All

check box if you want to pick the configurations to back up.

Check the box next to the option you want to backup.

Click the

Browse Local

button to specify a directory and file name for the backup .zip file.

In the Select dialog box, choose the directory in which you want to store the backup file.

Click

Select

.The path appears in the Backup File field.

Enter the name of the destination backup file after the directory path. The backup file name must be between 3 and 232 characters long.

Click

Backup

. Backup proceeds immediately unless you are backing up certificates or the ASA uses a master passphrase.

If you have configured and enabled a master passphrase on your ASA, you receive a warning message with a suggestion to change the master passphrase, if you do not know it, before proceeding with the backup. Click

Yes

to proceed with the backup if you know the master passphrase. Backup proceeds immediately unless you are backing up identity certificates.

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Step 11

If you are backing up an identity certificate, you receive a dialog asking you to enter a separate passphrase to be used for encoding the certificates in PKCS12 format. You can enter a passphrase or skip this step.

Note

Identify certificates are backed up by this process, certificate authority certificates are not backed up.

OL-20339-01

Step 12

•

To encrypt certificates, enter and confirm your certificate passphrase in the Certificate Passphrase dialog box and click

OK

. You will need to remember the password you enter in this dialog box when restoring the certificates.

Clicking

Cancel

skips the step and does not backup certificates.

•

After clicking OK or cancel, the backup begins immediately.

After the backup is complete, the status window closes and the Backup Statistics dialog box opens and provides success and failure messages.


75-15



Note

Backup “failure messages” are most likely caused by the lack of an existing configuration for the types indicated.

Step 13

Click

OK

to close the Backup Statistics dialog box.

Modes


Firewall Mode

Routed

•


•


Multiple

•

Context

—

System

—

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Restoring Configurations

You can specify configurations and images to restore from a zip file on your local computer.

Before proceeding, note these other restrictions:

•

•

The zip file that you restore must be created by choosing the Tools > Backup Configurations option.

If you performed the backup with the master passphrase enabled, then you will need that master passphrase in order to restore the running configuration, start-up configuration, and VPN pre-shared keys from the backup you created. If you do not know the master passphrase for the ASA, those items will not be restored during the restore process. See

Configuring the Master Passphrase for

more information on master passphrases.

•

•

•

•

If you specified a certificate passphrase during the backup, you will be asked to provide that passphrase in order to restore the certificates. The default passphrase is cisco

.

The DAP configuration may depend on a specific running configuration, URL list, and CSD configuration.

The CSD configuration may depend on the version of the CSD image.

You can restore components, images, and configurations using backups made from the same adaptive security appliance type. You must start with a basic configuration that allows ASDM access.

To restore selected elements of the adaptive security appliance configuration, Cisco Secure Desktop image, or SSL VPN Client images and profiles, perform the following steps:

Step 1

Step 2

Choose

Tools > Restore Configurations

.

In the Restore Configurations dialog box, click

Browse Local Directory

, choose the zip file on your local computer that contains the configuration to restore, then click

Select

. The path and the zip filename appear in the Local File field.

Step 3

Click

Next

. The second Restore Configuration dialog box appears. Check the boxes next to the configurations you want to restore. All available SSL VPN configurations are selected by default.

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Step 4

Step 5

Click

Restore

.

If you specified a certificate passphrase with which to encrypt the certificates when you created the backup file, ASDM prompts you to enter the passphrase.

Step 6

If you chose to restore the running configuration, you receive a dialog box asking if you if you want to merge the running configuration, replace the running configuration, or skip this part of the restoration process.

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Downgrading Your Software

Step 7

Step 8

•

•

Merging configurations combines the current running configuration and the backed-up running configuration.

Replacing the running configuration uses the backed-up running configuration only.

Skipping the step does not restore the backed-up running configuration.

•

ASDM displays a status dialog box until the restore operation is finished.

If you replaced or merged the running configuration, you will need to close ASDM and restart it. If you did not restore the running configuration or the running configuration, you only need to refresh the

ASDM session for the changes to take effect.

Modes


Firewall Mode

Routed



Multiple

Context

• • •

—

System

—


When you upgrade to Version 8.3, your configuration is migrated. The old configuration is automatically stored in flash memory. For example, when you upgrade from Version 8.2(1) to 8.3(1), the old 8.2(1) configuration is stored in flash memory in a file called 8_2_1_0_startup_cfg.sav.

This section describes how to downgrade and includes the following topics:

•

Information About Activation Key Compatibility, page 75-19

•

Performing the Downgrade, page 75-20

Information About Activation Key Compatibility



•

Downgrading to Version 8.1 or earlier versions—After you upgrade, if you activate additional feature licenses that were introduced

before 8.2

, then the activation key continues to be compatible with earlier versions if you downgrade. However if you activate feature licenses that were introduced in Version 8.2 or later versions , then the activation key is not backwards compatible. If you have an incompatible license key, then see the following guidelines:

–

If you previously entered an activation key in an earlier version, then the adaptive security appliance uses that key (without any of the new licenses you activated in Version 8.2 or later versions).

–


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•

Downgrading to Version 8.2 or earlier versions—Version 8.3 introduced more robust time-based key usage as well as failover license changes:

–

–

If you have more than one time-based activation key active, when you downgrade, only the most recently activated time-based key can be active. Any other keys are made inactive.


Performing the Downgrade

To downgrade from Version 8.3, perform the following steps. See the “Backing Up and Restoring

Configurations, Images, and Profiles” section on page 75-13

for more information about configuration migration.

Detailed Steps

Step 1

Choose

Tools > Downgrade Software

.

The Downgrade Software dialog box appears.

Figure 1 Downgrade Software

Step 2

Step 3

Step 4

Step 5

Step 6

For the ASA Image, click

Select Image File

.

The Browse File Locations dialog box appears.


•

•

Remote Server

—Choose

ftp

,

smb

, or

http

from the drop-down list, and type the path to the old image file.

Flash File System

—Click

Browse Flash

to choose the old image file on the local flash file system.

For the Configuration, click

Browse Flash

to choose the pre-migration configuration file. (By default this was saved on disk0).

(Optional) In the Activation Key field, enter the old activation key if you need to revert to a pre-8.3 activation key.

See the

“Information About Activation Key Compatibility” section on page 75-19


Click

Downgrade

.

This tool is a shortcut for completing the following functions:

1.

Clearing the boot image configuration (

clear configure boot

).

2.

3.

Setting the boot image to be the old image (

boot system

).

(Optional) Entering a new activation key (

activation-key

).

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5.

6.

4.

Saving the running configuration to startup (

write memory

). This sets the BOOT environment variable to the old image, so when you reload, the old image is loaded.

Copying the old configuration to the startup configuration (

copy

old_config_url

startup-config

).

Reloading (

reload

).

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C H A P T E R

76

Troubleshooting

This chapter describes how to troubleshoot the adaptive security appliance, and includes the following sections:

•

Testing Your Configuration, page 76-1

•

•

Other Troubleshooting Tools, page 76-8

Common Problems, page 76-13

Testing Your Configuration

This section describes how to test connectivity for the single mode adaptive security appliance or for each security context, how to ping the adaptive security appliance interfaces, and how to allow hosts on one interface to ping through to hosts on another interface.


•

Pinging Adaptive Security Appliance Interfaces, page 76-1

•

•

•

•

Passing Traffic Through the Adaptive Security Appliance, page 76-3

Verifying ASA Configuration and Operation, and Testing Interfaces Using Ping, page 76-3

Determining Packet Routing with Traceroute, page 76-6

Tracing Packets with Packet Tracer, page 76-7

Pinging Adaptive Security Appliance Interfaces

To test whether the adaptive security appliance interfaces are up and running and that the adaptive security appliance and connected routers are operating correctly, you can ping the adaptive security appliance interfaces. To ping the adaptive security appliance interfaces, perform the following steps:

Step 1

Draw a diagram of your single-mode adaptive security appliance or security context that shows the interface names, security levels, and IP addresses.

Note

Although this procedure uses IP addresses, the

ping

command also supports DNS names and names that are assigned to a local IP address with the

name

command.


76-1 OL-20339-01

Chapter 76 Troubleshooting


The diagram should also include any directly connected routers, and a host on the other side of the router from which you will ping the adaptive security appliance. You will use this information in this procedure and in the procedure in the

“Passing Traffic Through the Adaptive Security Appliance” section on page 76-3 . For example:

Figure 76-1

Host

10.1.1.56

Network Diagram with Interfaces, Routers, and Hosts

Host

209.265.200.230

Host

10.1.3.6

Host

209.165.201.24

10.1.1.2

209.265.200.226

10.1.3.2

Router

192.168.1.2

dmz1

192.1

68.1.

dmz2

192.168.2.1

security40

192.168.2.2

Router

209.165.201.2

192.168.3.2

Router outside

209.165.201.1

security0 dmz3

192.1

68.3.

inside

192.168.0.1

security100

Routed Security

Appliance dmz4

192.168.4.1

security80

192.168.0.2

192.168.4.2

10.1.2.2

Router

10.1.0.2

Router

Router

10.1.4.2

Host

209.165.201.1

Router

10.1.0.1

outside security0

Transp. Security

Appliance 10.1.0.3

inside security100

10.1.2.90

Host

10.1.0.34

Host

10.1.4.67

10.1.0.2

10.1.1.1

Router

10.1.1.5

Host

Step 2

Ping each adaptive security appliance interface from the directly connected routers. For transparent mode, ping the management IP address. This test ensures that the adaptive security appliance interfaces are active and that the interface configuration is correct.

A ping might fail if the adaptive security appliance interface is not active, the interface configuration is incorrect, or if a switch between the adaptive security appliance and a router is down (see

Figure 76-2

).

In this case, no debug messages or syslog messages appear, because the packet never reaches the adaptive security appliance.

Figure 76-2

Ping

Ping Failure at the Adaptive Security Appliance Interface

Router

Security

Appliance

If the ping reaches the adaptive security appliance, and it responds, debugging messages similar to the following appear:

ICMP echo reply (len 32 id 1 seq 256) 209.165.201.1 > 209.165.201.2

ICMP echo request (len 32 id 1 seq 512) 209.165.201.2 > 209.165.201.1

76-2


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If the ping reply does not return to the router, then a switch loop or redundant IP addresses may exist

(see Figure 76-3

).

Figure 76-3

Ping

Ping Failure Because of IP Addressing Problems

Router

192.168.1.2

192.168.1.2

192.168.1.1

Security

Appliance

Step 3

Host

Ping each adaptive security appliance interface from a remote host. For transparent mode, ping the management IP address. This test checks whether the directly connected router can route the packet between the host and the adaptive security appliance, and whether the adaptive security appliance can correctly route the packet back to the host.

A ping might fail if the adaptive security appliance does not have a return route to the host through the intermediate router (see

Figure 76-4

). In this case, the debugging messages show that the ping was successful, but syslog message 110001 appears, indicating a routing failure.

Figure 76-4

Ping

Ping Failure Because the Security Appliance has No Return Route

?

Host

Router

Security

Appliance

Passing Traffic Through the Adaptive Security Appliance

After you successfully ping the adaptive security appliance interfaces, make sure traffic can pass successfully through the adaptive security appliance. For routed mode, this test shows that NAT is operating correctly, if configured. For transparent mode, which does not use NAT, this test confirms that the adaptive security appliance is operating correctly. If the ping fails in transparent mode, contact Cisco

TAC.

Verifying ASA Configuration and Operation, and Testing Interfaces Using Ping

The Ping tool is useful for verifying the configuration and operation of the adaptive security appliance and surrounding communications links, as well as for testing other network devices.


•

•

Pinging From an Adaptive Security Appliance Interface, page 76-4

Pinging to an Adaptive Security Appliance Interface, page 76-5

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76-3



•

•

Pinging Through the Adaptive Security Appliance Interface, page 76-5

Troubleshooting the Ping Tool, page 76-5

Using the Ping Tool, page 76-5

•

A ping is sent to an IP address and it returns a reply. This process enables network devices to discover, identify, and test each other.

The Ping tool uses ICMP (as described in RFC 777 and RFC 792) to define an echo request-and-reply transaction between two network devices. The echo request packet is sent to the IP address of a network device. The receiving device reverses the source and destination address and sends the packet back as the echo reply.

Administrators can use the ASDM Ping interactive diagnostic tool in these ways:

•

Loopback testing of two interfaces—A ping may be initiated from one interface to another on the same adaptive security appliance, as an external loopback test to verify basic “up” status and operation of each interface.

•

•

Pinging to an adaptive security appliance—The Ping tool can ping an interface on another adaptive security appliance to verify that it is up and responding.

Pinging through an adaptive security appliance—Ping packets originating from the Ping tool may pass through an intermediate adaptive security appliance on their way to a device. The echo packets will also pass through two of its interfaces as they return. This procedure can be used to perform a basic test of the interfaces, operation, and response time of the intermediate unit.

•

•

Pinging to test questionable operation of a network device—A ping may be initiated from an adaptive security appliance interface to a network device that is suspected of functioning incorrectly.

If the interface is configured correctly and an echo is not received, there may be problems with the device.

Pinging to test intermediate communications—A ping may be initiated from an adaptive security appliance interface to a network device that is known to be functioning correctly and returning echo requests. If the echo is received, the correct operation of any intermediate devices and physical connectivity is confirmed.

Pinging From an Adaptive Security Appliance Interface

For basic testing of an interface, you can initiate a ping from an adaptive security appliance interface to a network device that you know is functioning correctly and returning replies through the intermediate communications path. For basic testing, make sure you do the following:

•

Verify receipt of the ping from the adaptive security appliance interface by the “known good” device. If the ping is not received, a problem with the transmitting hardware or interface configuration may exist.

•

If the adaptive security appliance interface is configured correctly and it does not receive an echo reply from the “known good” device, problems with the interface hardware receiving function may exist. If a different interface with “known good” receiving capability can receive an echo after pinging the same “known good” device, the hardware receiving problem of the first interface is confirmed.

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Pinging to an Adaptive Security Appliance Interface

When you try to ping to an adaptive security appliance interface, verify that the pinging response (ICMP echo reply

)

is enabled for that interface by choosing

Tools > Ping

. When pinging is disabled, the adaptive security appliance cannot be detected by other devices or software applications, and does not respond to the ASDM Ping tool.

Pinging Through the Adaptive Security Appliance Interface

To verify that other types of network traffic from “known good” sources are being passed through the adaptive security appliance, choose

Monitoring > Interfaces > Interface Graphs

or an SNMP management station.

To enable internal hosts to ping external hosts, configure ICMP access correctly for both the inside and outside interfaces by choosing

Configuration > Firewall > Objects > IP Names

.

Troubleshooting the Ping Tool

When pings fail to receive an echo, it may be the result of a configuration or operational error in a adaptive security appliance, and not necessarily because of no response from the IP address being pinged. Before using the Ping tool to ping from, to, or through an adaptive security appliance interface, perform the following basic checks:

•

Verify that interfaces are configured by choosing


.

•

•

Verify that devices in the intermediate communications path, such as switches or routers, are correctly delivering other types of network traffic.

Make sure that traffic of other types from “known good” sources is being passed by choosing

Monitoring > Interfaces > Interface Graphs

.

Using the Ping Tool

To use the Ping tool, perform the following steps:

Step 1

Step 2


Tools > Ping

.

The Ping dialog box appears.

Enter the destination IP address for the ICMP echo request packets in the IP Address field.

Ping can also accept IPv6 addresses.

Note

If a hostname has been assigned in the Configuration > Firewall > Objects > IP Names pane, you can use the hostname in place of the IP address.

Step 3

Step 4

(Optional) Choose the adaptive security appliance interface that transmits the echo request packets from the drop-down list. If it is not specified, the adaptive security appliance checks the routing table to find the destination address and uses the required interface.

Click

Ping

to send an ICMP echo request packet from the specified or default interface to the specified

IP address and start the response timer.

The response appears in the Ping Output area. Three attempts are made to ping the IP address, and results display the following fields:


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Step 5

•

•

•

The IP address of the device pinged or a device name, if available. The name of the device, if assigned Hosts/Networks, may be displayed, even if NO response is the result.

When the ping is transmitted, a millisecond timer starts with a specified maximum, or timeout value.

This timer is useful for testing the relative response times of different routes or activity levels.

Example Ping output:

Sending 5, 100-byte ICMP Echos to out-pc, timeout is 2 seconds:

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms

If the ping fails, the output is as follows:

Sending 5, 100-byte ICMP Echos to 10.132.80.101, timeout is 2 seconds:

?????

Success rate is 0 percent (0/5)

To enter a new IP address, click

Clear Screen

to remove the previous response from the Ping output area.

Determining Packet Routing with Traceroute

The Traceroute tool helps you to determine the route that packets will take to their destination. The tool prints the result of each probe sent. Every line of output corresponds to a TTL value in increasing order.

The following table lists the output symbols printed by this tool.

Output Symbol

*

nn

msec

!N.

!H

!P

!A

?

Description

No response was received for the probe within the timeout period.

For each node, the round-trip time (in milliseconds) for the specified number of probes.

ICMP network unreachable.

ICMP host unreachable.

ICMP unreachable.

ICMP administratively prohibited.

Unknown ICMP error.

To use the Traceroute tool, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5


Tools > Traceroute

.

The Traceroute dialog box appears.

Enter the name of the host to which the route is traced. If the hostname is specified, define it by choosing

Configuration > Firewall > Objects > IP Names

, or configure a DNS server to enable this tool to resolve the hostname to an IP address.

Enter the amount of time in seconds to wait for a response before the connection times out. The default is three seconds.

Type the destination port used by the UDP probe messages. The default is 33434.

Enter the number of probes to be sent at each TTL level. The default is three.

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Step 6

Step 7

Step 8

Step 9

Step 10

Step 11

Specify the minimum and maximum TTL values for the first probes. The minimum default is one, but it can be set to a higher value to suppress the display of known hops. The maximum default is 30. The traceroute terminates when the packet reaches the destination or when the maximum value is reached.

Check the

Specify source interface or IP address

check box. Choose the source interface or IP address for the packet trace from the drop-down list. This IP address must be the IP address of one of the interfaces. In transparent mode, it must be the management IP address of the adaptive security appliance.

Check the

Reverse Resolve

check box to have the output display the names of hops encountered if name resolution is configured. Leave this check box unchecked to have the output display IP addresses.

Check the

Use ICMP

check box to specify the use of ICMP probe packets instead of UDP probe packets.

Click

Trace Route

to start the traceroute.

The Traceroute Output area displays detailed messages about the traceroute results.

Click

Clear Output

to start a new traceroute.

Tracing Packets with Packet Tracer

The packet tracer tool provides packet tracing for packet sniffing and network fault isolation, as well as detailed information about the packets and how they are processed by the adaptive security appliance. If a configuration command did not cause the packet to drop, the packet tracer tool provides information about the cause in an easily readable manner.

In addition, you can trace the lifespan of a packet through the adaptive security appliance to see whether the packet is operating correctly with the packet tracer tool. This tool lets you do the following:

•

•

•

Debug all packet drops in a production network.

Verify the configuration is working as intended.

Show all rules applicable to a packet, along with the CLI commands that caused the rule addition.

Show a time line of packet changes in a data path.

•

•

Inject tracer packets into the data path.

To open the packet tracer, perform the following steps:

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

Step 1


Tools > Packet Tracer

.

The Cisco ASDM Packet Tracer dialog box appears.

Choose the source interface for the packet trace from the drop-down list.

Specify the protocol type for the packet trace. Available protocol types include ICMP, IP, TCP, and UDP.

Enter the source address for the packet trace in the Source IP Address field.

Choose the source port for the packet trace from the drop-down list.

Enter the destination IP address for the packet trace in the Destination IP Address field.

Choose the destination port for the packet trace from the drop-down list.

Click

Start

to trace the packet.

The Information Display Area shows detailed messages about the packet trace.

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Other Troubleshooting Tools

Note

To display a graphical representation of the packet trace, check the

Show animation

check box.


The adaptive security appliance provides other troubleshooting tools that you can use. This section includes the following topics:

•

•

•

Configuring and Running Captures with the Packet Capture Wizard, page 76-8

Sending an Administrator’s Alert to Clientless SSL VPN Users, page 76-12

Saving an Internal Log Buffer to Flash, page 76-12

•

Viewing and Copying Logged Entries with the ASDM Java Console, page 76-12

Configuring and Running Captures with the Packet Capture Wizard

You can use the Packet Capture Wizard to configure and run captures for troubleshooting errors. The captures can use access lists to limit the type of traffic captured, the source and destination addresses and ports, and one or more interfaces. The wizard runs one capture on each of the ingress and egress interfaces. You can save the captures on your PC to examine them in a packet analyzer.

Note

This tool does not support clientless SSL VPN capture.

To configure and run captures, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7


Wizards > Packet Capture Wizard

.

The Overview of Packet Capture screen appears, with a list of the tasks through which the wizard will guide you to complete.

Click

Next

to display the Ingress Traffic Selector screen.

Choose the ingress interface from the drop-down list.

In the Packet Match Criteria area, do one of the following:

•

To specify the access list to use for matching packets, click the

Specify access-list

radio button, and then choose the access list from the Select access list drop-down list. To add a previously configured access list to the current drop-down list, click

Manage

to display the ACL Manager pane. Choose an access list, and click

OK

.

•

To specify packets parameters, click the

Specify Packet Parameters

radio button.

Click

Next

to display the Ingress Traffic Selector screen. For more information, see the “Ingress Traffic

Selector” section on page 76-10

.

Enter the source host IP address and choose the network IP address from the drop-down list.

Enter the destination host IP address and choose the network IP address from the drop-down list.

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Step 8

Step 9

Step 10

Step 11

Step 12

Choose the protocol type to capture from the drop-down list. Available protocol types to capture are ah, eigrp, esp, gre, icmp, icmp6, igmp, igrp, ip, ipinip, nos, ospf, pcp, pim, snp, tcp, or udp.

Click

Next

to display the Egress Traffic Selector screen. For more information, see the

“Egress Traffic

Selector” section on page 76-10 .

Choose the egress interface from the drop-down list.

Enter the source host IP address and choose the network IP address from the drop-down list.

Enter the destination host IP address and choose the network IP address from the drop-down list.

Note

The source port services, destination port services, and ICMP type are read-only and are based on the choices that you made in the Ingress Traffic Selector screen.

Step 13

Step 14

Step 15

Click

Next

to display the Buffers & Captures screen. For more information, see the “Buffers” section on page 76-10

.

In the Capture Parameters area, to obtain the latest capture every 10 seconds automatically, check the

Get capture every 10 seconds

check box. By default, this capture uses the circular buffer.

In the Buffer Parameters area, you specify the buffer size and packet size. The buffer size is the maximum amount of memory that the capture can use to store packets. The packet size is the longest packet that the capture can hold. We recommend that you use the longest packet size to capture as much information as possible.

a.

b.

c.

Enter the packet size. The valid size ranges from 14 - 1522 bytes.

Enter the buffer size. The valid size ranges from 1534 - 33554432 bytes.

Check the

Use circular buffer

check box to store captured packets.

Note

When you choose this setting, if all the buffer storage is used, the capture starts overwriting the oldest packets.

Step 16

Step 17

Step 18

Step 19

Step 20

Step 21

Step 22

Step 23

Click

Next

to display the Summary screen, which shows the traffic selectors and buffer parameters that you have entered. For more information, see the

“Summary” section on page 76-11 .

Click

Next

to display the Run Captures screen, and then click

Start

to begin capturing packets. Click

Stop

to end the capture. For more information, see the

“Run Captures” section on page 76-11 .

Click

Get Capture Buffer

to determine how much buffer space you have remaining. Click

Clear Buffer on Device

to remove the current content and allow room in the buffer to capture more packets.

Click

Save captures

to display the Save Capture dialog box. Choose the format in which you want to include the captures:

ASCII

or

PCAP

. You have the option of saving either the ingress capture, the egress capture, or both.

To save the ingress packet capture, click

Save Ingress Capture

to display the Save capture file dialog box. Specify the storage location on your PC, and click

Save

.

Click

Launch Network Sniffer Application

to start the packet analysis application specified in Tools

> Preferences for analyzing the ingress capture.

To save the egress packet capture, click

Save Egress Capture

to display the Save capture file dialog box.

Specify the storage location on your PC, and click

Save

.

Click


to start the packet analysis application specified in Tools

> Preferences for analyzing the egress capture.

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76-9



Step 24

Click

Close,

and then click

Finish

to exit the wizard.

Ingress Traffic Selector

To configure the ingress interface, source and destination hosts/networks, and the protocol for packet capture, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Enter the ingress interface name.

Enter the ingress source host and network.

Enter the ingress destination host and network.

Enter the protocol type to capture. Available protocols are ah, eigrp, esp, gre, icmp, icmp6, igmp, igrp, ip, ipinip, nos, ospf, pcp, pim, snp, tcp, or udp.

a.

b.

Enter the ICMP type for ICMP only. Available types include all, alternate address, conversion-error, echo, echo-reply, information-reply, information-request, mask-reply, mask-request, mobile-redirect, parameter-problem, redirect, router-advertisement, router-solicitation, source-quench, time-exceeded, timestamp-reply, timestamp-request, traceroute, or unreachable.

Specify the source and destination port services for the TCP and UDP protocols only. Available options include the following:

–

–

To include all services, choose All Services.

To include a service group, choose Service Groups.

–

To include a specific service, choose one of the following: aol, bgp, chargen, cifx, citrix-ica, ctiqbe, daytime, discard, domain, echo, exec, finger, ftp, ftp-data, gopher, h323, hostname, http, https, ident, imap4, irc, kerberos, klogin, kshell, ldap, ldaps, login, lotusnotes, lpd, netbios-ssn, nntp, pcanywhere-data, pim-auto-rp, pop2, pop3, pptp, rsh, rtsp, sip, smtp, sqlnet, ssh, sunrpc, tacacs, talk, telnet, uucp, or whois.

Egress Traffic Selector

To configure the egress interface, source and destination hosts/networks, and source and destination port services for packet capture, perform the following steps:

Step 1

Step 2

Step 3

Enter the egress interface name.

Enter the egress source host and network.

Enter the egress destination host and network.

The protocol type selected during the ingress configuration is already listed.

Buffers

To configure the packet size, buffer size, and use of the circular buffer for packet capture, perform the following steps.

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Step 1

Step 2

Step 3

Enter the longest packet that the capture can hold. Use the longest size available to capture as much information as possible.

Enter the maximum amount of memory that the capture can use to store packets.

Use the circular buffer to store packets. When the circular buffer has used all of the buffer storage, the capture will overwrite the oldest packets first.

Summary

The Summary screen shows the traffic selectors and the buffer parameters for the packet capture selected in the previous wizard screens.

Run Captures

To start and stop the capture session, view the capture buffer, launch a network analyzer application, save packet captures, and clear the buffer, perform the following steps:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 7

Step 8

To begin the packet capture session on a selected interface, click

Start

.

To stop the packet capture session on a selected interface, click

Stop

.

To obtain a snapshot of the captured packets on the interface, click

Get Capture Buffer

.

To show the capture buffer on the ingress interface, click

Ingress

.

To show the capture buffer on the egress interface, click

Egress

.

To clear the buffer on the device, click

Clear Buffer on Device

.

To start the packet analysis application for analyzing the ingress capture or the egress capture specified in Tools > Preferences, click


.

To save the ingress and egress captures in either ASCII or PCAP format, click

Save Captures

.

Save Captures

To save the ingress and egress packet captures to ASCII or PCAP file format for further packet analysis, perform the following steps:

Step 1

Step 2

Step 3

Step 4

To save the capture buffer in ASCII format, click

ASCII

.

To save the capture buffer in PCAP format, click

PCAP

.

To specify a file in which to save the ingress packet capture, click

Save ingress capture

.

To specify a file in which to save the egress packet capture, click

Save egress capture

.

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76-11



Sending an Administrator’s Alert to Clientless SSL VPN Users

This feature lets you send an alert message to clientless SSL VPN users (for example, about connection status).

To send an alert message, perform the following steps:

Step 1

Step 2

Step 3


Tools > Administrator’s Alert Message to Clientless

SSL VPN Users

.

The Administrator’s Alert Message to Clientless SSL VPN Users dialog box appears.

Enter the new or edited alert content that you want to send, and then click

Post Alert

.

To remove current alert content and enter new alert content, click

Cancel Alert

.

Saving an Internal Log Buffer to Flash

This feature lets you save the internal log buffer to flash memory.

To save the internal log buffer to flash memory, perform the following steps:

Step 1

Step 2

Step 3

Step 4


File > Save Internal Log Buffer to Flash

.

The Enter Log File Name dialog box appears.

Choose the first option to save the log buffer with the default filename,

LOG-YYYY-MM-DD-hhmmss.txt.

Choose the second option to specify a filename for the log buffer.

Enter the filename for the log buffer, and then click

OK

.

Viewing and Copying Logged Entries with the ASDM Java Console

You can use the ASDM Java console to view and copy logged entries in a text format, which can help you troubleshoot ASDM errors.

To access the ASDM Java Console, perform the following steps:

Step 1

Step 2

Step 3

Step 4


Tools > ASDM Java Console

.

To show the virtual machine memory statistics, enter

m

in the console.

To perform garbage collection, enter

g

in the console.

To monitor memory usage, open the Windows Task Manager and double-click the

asdm_launcher.exe

file.

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Note

The maximum memory allocation allowed is 256 MB.

Common Problems

Common Problems

This section describes common problems with the adaptive security appliance, and how you might resolve them.

Symptom

The context configuration was not saved, and was lost when you reloaded.

Possible Cause

You did not save each context within the context execution space. If you are configuring contexts at the command line, you did not save the current context before you changed to the next context.

Recommended Action

Save each context within the context execution space using the

copy run start

command. You cannot save contexts from the system execution space.

Symptom

You cannot make a Telnet or SSH connection to the adaptive security appliance interface.

Possible Cause

You did not enable Telnet or SSH to the adaptive security appliance.


Enable Telnet or SSH to the adaptive security appliance according to the instructions in

“Configuring Device Access for ASDM, Telnet, or SSH” section on page 32-1 .

Symptom

You cannot ping the adaptive security appliance interface.

Possible Cause

You disabled ICMP to the adaptive security appliance.

Recommended Action icmp

command.

Enable ICMP to the adaptive security appliance for your IP address using the

Symptom

You cannot ping through the adaptive security appliance, although the access list allows it.

Possible Cause

You did not enable the ICMP inspection engine or apply access lists on both the ingress and egress interfaces.


Because ICMP is a connectionless protocol, the adaptive security appliance does not automatically allow returning traffic through. In addition to an access list on the ingress interface, you either need to apply an access list to the egress interface to allow replying traffic, or enable the ICMP inspection engine, which treats ICMP connections as stateful connections.

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76-13

Common Problems


Symptom

Traffic does not pass between two interfaces on the same security level.

Possible Cause

You did not enable the feature that allows traffic to pass between interfaces at the same security level.


Enable this feature according to the instructions in

“Allowing Same Security

Level Communication” section on page 8-31

.

Symptom

IPSec tunnels do not duplicate during a failover to the standby device.

Possible Cause

The switch port that the adaptive security appliance is plugged into is set to 10/100 instead of 1000.


Set the switch port that the adaptive security appliance is plugged into to 1000.

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Common Problems

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76-15

Common Problems


76-16


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Common Problems

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76-17

Common Problems


76-18


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Common Problems

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76-19

Common Problems


76-20


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Common Problems

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Common Problems


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P

A R T

1 7

Reference

A P P E N D I X

A

Addresses, Protocols, and Ports

This appendix provides a quick reference for IP addresses, protocols, and applications. This appendix includes the following sections:

•

IPv4 Addresses and Subnet Masks, page A-1

•

•

•

•

•

IPv6 Addresses, page A-5

Protocols and Applications, page A-11

TCP and UDP Ports, page A-11

Local Ports and Protocols, page A-14

ICMP Types, page A-15

IPv4 Addresses and Subnet Masks

This section describes how to use IPv4 addresses in the adaptive security appliance. An IPv4 address is a 32-bit number written in dotted-decimal notation: four 8-bit fields (octets) converted from binary to decimal numbers, separated by dots. The first part of an IP address identifies the network on which the host resides, while the second part identifies the particular host on the given network. The network number field is called the network prefix. All hosts on a given network share the same network prefix but must have a unique host number. In classful IP, the class of the address determines the boundary between the network prefix and the host number.


•

•

•

Classes, page A-1

Private Networks, page A-2

Subnet Masks, page A-2

Classes

IP host addresses are divided into three different address classes: Class A, Class B, and Class C. Each class fixes the boundary between the network prefix and the host number at a different point within the

32-bit address. Class D addresses are reserved for multicast IP.

•

Class A addresses (1.xxx.xxx.xxx through 126.xxx.xxx.xxx) use only the first octet as the network prefix.


A-1 OL-20339-01

Appendix A Addresses, Protocols, and Ports


•

Class B addresses (128.0.xxx.xxx through 191.255.xxx.xxx) use the first two octets as the network prefix.

•

Class C addresses (192.0.0.xxx through 223.255.255.xxx) use the first three octets as the network prefix.

Because Class A addresses have 16,777,214 host addresses, and Class B addresses 65,534 hosts, you can use subnet masking to break these huge networks into smaller subnets.

Private Networks

If you need large numbers of addresses on your network, and they do not need to be routed on the

Internet, you can use private IP addresses that the Internet Assigned Numbers Authority (IANA) recommends (see RFC 1918). The following address ranges are designated as private networks that should not be advertised:

•

10.0.0.0 through 10.255.255.255

•

•

172.16.0.0 through 172.31.255.255

192.168.0.0 through 192.168.255.255

Subnet Masks

A subnet mask lets you convert a single Class A, B, or C network into multiple networks. With a subnet mask, you can create an extended network prefix that adds bits from the host number to the network prefix. For example, a Class C network prefix always consists of the first three octets of the IP address.

But a Class C extended network prefix uses part of the fourth octet as well.

Subnet masking is easy to understand if you use binary notation instead of dotted decimal. The bits in the subnet mask have a one-to-one correspondence with the Internet address:

•

•

The bits are set to 1 if the corresponding bit in the IP address is part of the extended network prefix.

The bits are set to 0 if the bit is part of the host number.

Example 1:

If you have the Class B address 129.10.0.0 and you want to use the entire third octet as part of the extended network prefix instead of the host number, you must specify a subnet mask of

11111111.11111111.11111111.00000000. This subnet mask converts the Class B address into the equivalent of a Class C address, where the host number consists of the last octet only.

Example 2:

If you want to use only part of the third octet for the extended network prefix, then you must specify a subnet mask like 11111111.11111111.11111000.00000000, which uses only 5 bits of the third octet for the extended network prefix.

You can write a subnet mask as a dotted-decimal mask or as a /

bits

(“slash

bits

”) mask. In Example 1, for a dotted-decimal mask, you convert each binary octet into a decimal number: 255.255.255.0. For a

/

bits

mask, you add the number of 1s: /24. In Example 2, the decimal number is 255.255.248.0 and the

/bits is /21.

You can also supernet multiple Class C networks into a larger network by using part of the third octet for the extended network prefix. For example, 192.168.0.0/20.


•

Determining the Subnet Mask, page A-3

•

Determining the Address to Use with the Subnet Mask, page A-3

A-2


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Determining the Subnet Mask

To determine the subnet mask based on how many hosts you want, see

Table A-1 .

Table A-1 Hosts, Bits, and Dotted-Decimal Masks

Hosts

1

16,777,216

65,536

32,768

16,384

8192

4096

2048

1024

8

4

32

16

512

256

128

64

Do not use

1

/Bits Mask

/8

/16

/17 255.255.128.0

/18 255.255.192.0

/19

/20 255.255.240.0

/21 255.255.248.0

/22 255.255.252.0

/23 255.255.254.0

/24

/25 255.255.255.128

/26 255.255.255.192

/27 255.255.255.224

/28 255.255.255.240

/29 255.255.255.248

/30 255.255.255.252

/31

/32

Dotted-Decimal Mask

255.0.0.0 Class A Network

255.255.0.0 Class B Network

255.255.224.0

255.255.255.0 Class C Network

255.255.255.254

255.255.255.255 Single Host Address

1.

The first and last number of a subnet are reserved, except for /32, which identifies a single host.

Determining the Address to Use with the Subnet Mask

The following sections describe how to determine the network address to use with a subnet mask for a

Class C-size and a Class B-size network. This section includes the following topics:

•

•

Class C-Size Network Address, page A-3

Class B-Size Network Address, page A-4

Class C-Size Network Address

For a network between 2 and 254 hosts, the fourth octet falls on a multiple of the number of host addresses, starting with 0. For example,

Table A-2

shows the 8-host subnets (/29) of 192.168.0.x.

Table A-2 Class C-Size Network Address

Subnet with Mask /29 (255.255.255.248)

192.168.0.0

192.168.0.8

Address Range

1

192.168.0.0 to 192.168.0.7

192.168.0.8 to 192.168.0.15


OL-20339-01 A-3



Table A-2 Class C-Size Network Address (continued)

Subnet with Mask /29 (255.255.255.248)

192.168.0.16

…

192.168.0.248

Address Range

1

192.168.0.16 to 192.168.0.31

…

192.168.0.248 to 192.168.0.255

1.

The first and last address of a subnet are reserved. In the first subnet example, you cannot use 192.168.0.0 or 192.168.0.7.

Class B-Size Network Address

To determine the network address to use with the subnet mask for a network with between 254 and

65,534 hosts, you need to determine the value of the third octet for each possible extended network prefix. For example, you might want to subnet an address like 10.1.

x

.0, where the first two octets are fixed because they are used in the extended network prefix, and the fourth octet is 0 because all bits are used for the host number.

To determine the value of the third octet, follow these steps:

Step 1

Step 2

Calculate how many subnets you can make from the network by dividing 65,536 (the total number of addresses using the third and fourth octet) by the number of host addresses you want.

For example, 65,536 divided by 4096 hosts equals 16.

Therefore, there are 16 subnets of 4096 addresses each in a Class B-size network.

Determine the multiple of the third octet value by dividing 256 (the number of values for the third octet) by the number of subnets:

In this example, 256/16 = 16.

The third octet falls on a multiple of 16, starting with 0.

Therefore,

Table A-3 shows the 16 subnets of the network 10.1.

Table A-3 Subnets of Network

Subnet with Mask /20 (255.255.240.0)

10.1.0.0

10.1.16.0

10.1.32.0

…

10.1.240.0

Address Range

1

10.1.0.0 to 10.1.15.255

10.1.16.0 to 10.1.31.255

10.1.32.0 to 10.1.47.255

…

10.1.240.0 to 10.1.255.255

1.

The first and last address of a subnet are reserved. In the first subnet example, you cannot use

10.1.0.0 or 10.1.15.255.

A-4


OL-20339-01


IPv6 Addresses

IPv6 Addresses

IPv6 is the next generation of the Internet Protocol after IPv4. It provides an expanded address space, a simplified header format, improved support for extensions and options, flow labeling capability, and authentication and privacy capabilities. IPv6 is described in RFC 2460. The IPv6 addressing architecture is described in RFC 3513.

This section describes the IPv6 address format and architecture and includes the following topics:

•

•

•

IPv6 Address Format, page A-5

IPv6 Address Types, page A-6

IPv6 Address Prefixes, page A-10

Note

This section describes the IPv6 address format, the types, and prefixes. For information about configuring the adaptive security appliance to use IPv6, see the

“Configuring IPv6 Addressing” section on page 8-27

IPv6 Address Format

IPv6 addresses are represented as a series of eight 16-bit hexadecimal fields separated by colons (:) in the format: x:x:x:x:x:x:x:x. The following are two examples of IPv6 addresses:

•

2001:0DB8:7654:3210:FEDC:BA98:7654:3210

•

2001:0DB8:0000:0000:0008:0800:200C:417A

Note

The hexadecimal letters in IPv6 addresses are not case-sensitive.

You do not need to include the leading zeros in an individual field of the address, but each field must contain at least one digit. So the example address 2001:0DB8:0000:0000:0008:0800:200C:417A can be shortened to 2001:0DB8:0:0:8:800:200C:417A by removing the leading zeros from the third through sixth fields from the left. The fields that contained all zeros (the third and fourth fields from the left) were shortened to a single zero. The fifth field from the left had the three leading zeros removed, leaving a single 8 in that field, and the sixth field from the left had the one leading zero removed, leaving 800 in that field.

It is common for IPv6 addresses to contain several consecutive hexadecimal fields of zeros. You can use two colons (::) to compress consecutive fields of zeros at the beginning, middle, or end of an IPv6 address (the colons represent the successive hexadecimal fields of zeros).

Table A-4

shows several examples of address compression for different types of IPv6 address.

Table A-4 IPv6 Address Compression Examples

Address Type Standard Form

Unicast

Multicast

Compressed Form

2001:0DB8:0:0:0:BA98:0:3210 2001:0DB8::BA98:0:3210

FF01:0:0:0:0:0:0:101 FF01::101

Loopback 0:0:0:0:0:0:0:1

Unspecified 0:0:0:0:0:0:0:0

::1

::

OL-20339-01


A-5


IPv6 Addresses

Note

Two colons (::) can be used only once in an IPv6 address to represent successive fields of zeros.

An alternative form of the IPv6 format is often used when dealing with an environment that contains both IPv4 and IPv6 addresses. This alternative has the format x:x:x:x:x:x:y.y.y.y, where x represent the hexadecimal values for the six high-order parts of the IPv6 address and y represent decimal values for the 32-bit IPv4 part of the address (which takes the place of the remaining two 16-bit parts of the IPv6 address). For example, the IPv4 address 192.168.1.1 could be represented as the IPv6 address

0:0:0:0:0:0:FFFF:192.168.1.1 or ::FFFF:192.168.1.1.

IPv6 Address Types

The following are the three main types of IPv6 addresses:

•

•

•

Unicast

—A unicast address is an identifier for a single interface. A packet sent to a unicast address is delivered to the interface identified by that address. An interface may have more than one unicast address assigned to it.

Multicast

—A multicast address is an identifier for a set of interfaces. A packet sent to a multicast address is delivered to all addresses identified by that address.

Anycast

—An anycast address is an identifier for a set of interfaces. Unlike a multicast address, a packet sent to an anycast address is only delivered to the “nearest” interface, as determined by the measure of distances for the routing protocol.

Note

There are no broadcast addresses in IPv6. Multicast addresses provide the broadcast functionality.


•

•

Unicast Addresses, page A-6

Multicast Address, page A-8

•

•

Anycast Address, page A-9

Required Addresses, page A-10

Unicast Addresses

This section describes IPv6 unicast addresses. Unicast addresses identify an interface on a network node.


•

Global Address, page A-7

•

•

•

•

•

•

Site-Local Address, page A-7

Link-Local Address, page A-7

IPv4-Compatible IPv6 Addresses, page A-7

Unspecified Address, page A-8

Loopback Address, page A-8

Interface Identifiers, page A-8

A-6


OL-20339-01


IPv6 Addresses

Global Address

The general format of an IPv6 global unicast address is a global routing prefix followed by a subnet ID followed by an interface ID. The global routing prefix can be any prefix not reserved by another IPv6 address type (see the

“IPv6 Address Prefixes” section on page A-10

, for information about the IPv6 address type prefixes).

All global unicast addresses, other than those that start with binary 000, have a 64-bit interface ID in the

Modified EUI-64 format. See the

“Interface Identifiers” section on page A-8

, for more information about the Modified EUI-64 format for interface identifiers.

Global unicast address that start with the binary 000 do not have any constraints on the size or structure of the interface ID portion of the address. One example of this type of address is an IPv6 address with an embedded IPv4 address (see the

“IPv4-Compatible IPv6 Addresses” section on page A-7 ).

Site-Local Address

Site-local addresses are used for addressing within a site. They can be use to address an entire site without using a globally unique prefix. Site-local addresses have the prefix FEC0::/10, followed by a

54-bit subnet ID, and end with a 64-bit interface ID in the modified EUI-64 format.

Site-local routers do not forward any packets that have a site-local address for a source or destination outside of the site. Therefore, site-local addresses can be considered private addresses.

Link-Local Address

All interfaces are required to have at least one link-local address. You can configure multiple IPv6 addresses per interfaces, but only one link-local address.

A link-local address is an IPv6 unicast address that can be automatically configured on any interface using the link-local prefix FE80::/10 and the interface identifier in modified EUI-64 format. Link-local addresses are used in the neighbor discovery protocol and the stateless autoconfiguration process. Nodes with a link-local address can communicate; they do not need a site-local or globally unique address to communicate.

Routers do not forward any packets that have a link-local address for a source or destination. Therefore, link-local addresses can be considered private addresses.

IPv4-Compatible IPv6 Addresses

There are two types of IPv6 addresses that can contain IPv4 addresses.

The first type is the IPv4-compatibly IPv6 address. The IPv6 transition mechanisms include a technique for hosts and routers to dynamically tunnel IPv6 packets over IPv4 routing infrastructure. IPv6 nodes that use this technique are assigned special IPv6 unicast addresses that carry a global IPv4 address in the low-order 32 bits. This type of address is termed an IPv4-compatible IPv6 address and has the format

::y.y.y.y, where y.y.y.y is an IPv4 unicast address.

Note

The IPv4 address used in the IPv4-compatible IPv6 address must be a globally-unique IPv4 unicast address.

The second type of IPv6 address, which holds an embedded IPv4 address, is called the IPv4-mapped

IPv6 address. This address type is used to represent the addresses of IPv4 nodes as IPv6 addresses. This type of address has the format ::FFFF:y.y.y.y, where y.y.y.y is an IPv4 unicast address.

OL-20339-01


A-7


IPv6 Addresses

Unspecified Address

The unspecified address, 0:0:0:0:0:0:0:0, indicates the absence of an IPv6 address. For example, a newly initialized node on an IPv6 network may use the unspecified address as the source address in its packets until it receives its IPv6 address.

Note

The IPv6 unspecified address cannot be assigned to an interface. The unspecified IPv6 addresses must not be used as destination addresses in IPv6 packets or the IPv6 routing header.

Loopback Address

The loopback address, 0:0:0:0:0:0:0:1, may be used by a node to send an IPv6 packet to itself. The loopback address in IPv6 functions the same as the loopback address in IPv4 (127.0.0.1).

Note

The IPv6 loopback address cannot be assigned to a physical interface. A packet that has the IPv6 loopback address as its source or destination address must remain within the node that created the packet.

IPv6 routers do not forward packets that have the IPv6 loopback address as their source or destination address.

Interface Identifiers

Interface identifiers in IPv6 unicast addresses are used to identify the interfaces on a link. They need to be unique within a subnet prefix. In many cases, the interface identifier is derived from the interface link-layer address. The same interface identifier may be used on multiple interfaces of a single node, as long as those interfaces are attached to different subnets.

For all unicast addresses, except those that start with the binary 000, the interface identifier is required to be 64 bits long and to be constructed in the Modified EUI-64 format. The Modified EUI-64 format is created from the 48-bit MAC address by inverting the universal/local bit in the address and by inserting the hexadecimal number FFFE between the upper three bytes and lower three bytes of the of the MAC address.

For example, and interface with the MAC address of 00E0.b601.3B7A would have a 64-bit interface ID of 02E0:B6FF:FE01:3B7A.

Multicast Address

An IPv6 multicast address is an identifier for a group of interfaces, typically on different nodes. A packet sent to a multicast address is delivered to all interfaces identified by the multicast address. An interface may belong to any number of multicast groups.

An IPv6 multicast address has a prefix of FF00::/8 (1111 1111). The octet following the prefix defines the type and scope of the multicast address. A permanently assigned (well known) multicast address has a flag parameter equal to 0; a temporary (transient) multicast address has a flag parameter equal to 1. A multicast address that has the scope of a node, link, site, or organization, or a global scope has a scope parameter of 1, 2, 5, 8, or E, respectively. For example, a multicast address with the prefix FF02::/16 is

a permanent multicast address with a link scope. Figure A-1 shows the format of the IPv6 multicast

address.

A-8


OL-20339-01


Figure A-1 IPv6 Multicast Address Format

128 bits

Interface ID 0

1111 1111

F F

4 bits 4 bits

Flag Scope

8 bits 8 bits

Flag =

0 if permanent

1 if temporary

Scope =

1 = node

2 = link

4 = admin

5 = site

8 = organization

E = global

IPv6 Addresses

IPv6 nodes (hosts and routers) are required to join the following multicast groups:

•

The All Nodes multicast addresses:

–

FF01:: (interface-local)

•

–

FF02:: (link-local)

The Solicited-Node Address for each IPv6 unicast and anycast address on the node:

FF02:0:0:0:0:1:FFXX:XXXX/104, where XX:XXXX is the low-order 24-bits of the unicast or anycast address.

Note

Solicited-Node addresses are used in Neighbor Solicitation messages.

IPv6 routers are required to join the following multicast groups:

•

•

•

FF01::2 (interface-local)

FF02::2 (link-local)

FF05::2 (site-local)

Multicast address should not be used as source addresses in IPv6 packets.

Note

There are no broadcast addresses in IPv6. IPv6 multicast addresses are used instead of broadcast addresses.

Anycast Address

The IPv6 anycast address is a unicast address that is assigned to more than one interface (typically belonging to different nodes). A packet that is routed to an anycast address is routed to the nearest interface having that address, the nearness being determined by the routing protocol in effect.

Anycast addresses are allocated from the unicast address space. An anycast address is simply a unicast address that has been assigned to more than one interface, and the interfaces must be configured to recognize the address as an anycast address.

The following restrictions apply to anycast addresses:

•

An anycast address cannot be used as the source address for an IPv6 packet.


OL-20339-01 A-9

IPv6 Addresses


•

An anycast address cannot be assigned to an IPv6 host; it can only be assigned to an IPv6 router.

Note

Anycast addresses are not supported on the adaptive security appliance.

Required Addresses

IPv6 hosts must, at a minimum, be configured with the following addresses (either automatically or manually):

•

A link-local address for each interface.

•

•

The loopback address.

The All-Nodes multicast addresses

•

A Solicited-Node multicast address for each unicast or anycast address.

IPv6 routers must, at a minimum, be configured with the following addresses (either automatically or manually):

•

•

•

The required host addresses.

The Subnet-Router anycast addresses for all interfaces for which it is configured to act as a router.

The All-Routers multicast addresses.

IPv6 Address Prefixes

An IPv6 address prefix, in the format ipv6-prefix/prefix-length, can be used to represent bit-wise contiguous blocks of the entire address space. The IPv6-prefix must be in the form documented in RFC

2373 where the address is specified in hexadecimal using 16-bit values between colons. The prefix length is a decimal value that indicates how many of the high-order contiguous bits of the address comprise the prefix (the network portion of the address). For example, 2001:0DB8:8086:6502::/32 is a valid IPv6 prefix.

The IPv6 prefix identifies the type of IPv6 address.

Table A-5 shows the prefixes for each IPv6 address

type.

Table A-5 IPv6 Address Type Prefixes

Address Type

Unspecified

Binary Prefix

000...0 (128 bits)

IPv6 Notation

::/128

Loopback

Multicast

000...1 (128 bits)

11111111

Link-Local (unicast) 1111111010

::1/128

FF00::/8

FE80::/10

FEC0::/10 Site-Local (unicast) 1111111111

Global (unicast) All other addresses.

Anycast Taken from the unicast address space.

A-10


OL-20339-01


Protocols and Applications

Protocols and Applications

Table A-6 lists the protocol literal values and port numbers; either can be entered in adaptive security

appliance commands.

Table A-6 Protocol Literal Values

Literal Value Description

ah 51 Authentication Header for IPv6, RFC 1826.

eigrp 88 esp 50

Enhanced Interior Gateway Routing Protocol.

Encapsulated Security Payload for IPv6, RFC 1827.

gre 47 icmp 1 icmp6 58 igmp 2

Generic Routing Encapsulation.

Internet Control Message Protocol, RFC 792.

Internet Control Message Protocol for IPv6, RFC 2463.

Internet Group Management Protocol, RFC 1112.

igrp ip

9

0 ipinip 4 ipsec 50

Interior Gateway Routing Protocol.

Internet Protocol.

IP-in-IP encapsulation.

IP Security. Entering the ipsec protocol literal is equivalent to entering the esp protocol literal.

nos 94 ospf 89 pcp pim

Network Operating System (Novell’s NetWare).

Open Shortest Path First routing protocol, RFC 1247.

108 Payload Compression Protocol.

103 Protocol Independent Multicast.

pptp snp

47 Point-to-Point Tunneling Protocol. Entering the pptp protocol literal is equivalent to entering the gre protocol literal.

109 Sitara Networks Protocol.

tcp udp

6

17

Transmission Control Protocol, RFC 793.

User Datagram Protocol, RFC 768.

Protocol numbers can be viewed online at the IANA website: http://www.iana.org/assignments/protocol-numbers

TCP and UDP Ports

Table A-7 lists the literal values and port numbers; either can be entered in adaptive security appliance

commands. See the following caveats:

•

The adaptive security appliance uses port 1521 for SQL*Net. This is the default port used by Oracle for SQL*Net. This value, however, does not agree with IANA port assignments.

OL-20339-01


A-11



•

The adaptive security appliance listens for RADIUS on ports 1645 and 1646. If your RADIUS server uses the standard ports 1812 and 1813, you can configure the adaptive security appliance to listen to those ports using the

authentication-port

and

accounting-port

commands.

•

To assign a port for DNS access, use the

domain

literal value, not

dns

. If you use

dns

, the adaptive security appliance assumes you meant to use the

dnsix

literal value.

Port numbers can be viewed online at the IANA website: http://www.iana.org/assignments/port-numbers

Table A-7 Port Literal Values

Literal

aol bgp biff bootpc bootps chargen citrix-ica cmd ctiqbe daytime discard domain dnsix echo exec finger ftp ftp-data gopher https h323 hostname ident imap4 irc

TCP or UDP? Value

TCP 5190

TCP

UDP

179

512

UDP

UDP

TCP

TCP

TCP

TCP

TCP

TCP, UDP

TCP, UDP

UDP

68

67

19

1494

514

2748

13

9

53

195

TCP, UDP 7

TCP 512

TCP

TCP

TCP

TCP

TCP

TCP

TCP

TCP

TCP

TCP

79

21

20

70

443

1720

101

113

143

194

Description

America Online

Border Gateway Protocol, RFC 1163

Used by mail system to notify users that new mail is received

Bootstrap Protocol Client

Bootstrap Protocol Server

Character Generator

Citrix Independent Computing Architecture (ICA) protocol

Similar to

exec

except that

cmd

has automatic authentication

Computer Telephony Interface Quick Buffer

Encoding

Day time, RFC 867

Discard

DNS

DNSIX Session Management Module Audit

Redirector

Echo

Remote process execution

Finger

File Transfer Protocol (control port)

File Transfer Protocol (data port)

Gopher

HTTP over SSL

H.323 call signalling

NIC Host Name Server

Ident authentication service

Internet Message Access Protocol, version 4

Internet Relay Chat protocol

A-12


OL-20339-01



Table A-7

Literal

isakmp kerberos klogin kshell ldap ldaps lpd login lotusnotes mobile-ip nameserver netbios-ns netbios-dgm netbios-ssn nntp pop2 pop3 pptp radius radius-acct rip secureid-udp smtp snmp snmptrap sqlnet ssh sunrpc (rpc) syslog

Port Literal Values (continued)


UDP 500

UDP

UDP

UDP

UDP ntp UDP pcanywhere-status UDP pcanywhere-data pim-auto-rp

TCP, UDP 750

TCP 543

TCP

TCP

544

389

TCP

TCP

TCP

TCP

TCP

TCP

636

515

513

1352

434

42

137

138

139

119

123

5632

TCP 5631

TCP, UDP 496

TCP

TCP

TCP

UDP

UDP

UDP

UDP

TCP

UDP

UDP

TCP

TCP

109

110

1723

1645

1646

520

5510

25

161

162

1521

22

TCP, UDP 111

UDP 514

Description

Internet Security Association and Key Management

Protocol

Kerberos

KLOGIN

Korn Shell

Lightweight Directory Access Protocol

Lightweight Directory Access Protocol (SSL)

Line Printer Daemon - printer spooler

Remote login

IBM Lotus Notes

MobileIP-Agent

Host Name Server

NetBIOS Name Service

NetBIOS Datagram Service

NetBIOS Session Service

Network News Transfer Protocol

Network Time Protocol pcAnywhere status pcAnywhere data

Protocol Independent Multicast, reverse path flooding, dense mode

Post Office Protocol - Version 2

Post Office Protocol - Version 3

Point-to-Point Tunneling Protocol

Remote Authentication Dial-In User Service

Remote Authentication Dial-In User Service

(accounting)

Routing Information Protocol

SecureID over UDP

Simple Mail Transport Protocol

Simple Network Management Protocol

Simple Network Management Protocol - Trap

Structured Query Language Network

Secure Shell

Sun Remote Procedure Call

System Log

OL-20339-01


A-13

Local Ports and Protocols

Table A-7

Literal

tacacs talk telnet tftp time uucp who whois www xdmcp


Port Literal Values (continued)


TCP, UDP 49

TCP, UDP

TCP

UDP

UDP

TCP

UDP

TCP

TCP

UDP

517

23

69

37

540

513

43

80

177

Description

Terminal Access Controller Access Control System

Plus

Talk

RFC 854 Telnet

Trivial File Transfer Protocol

Time

UNIX-to-UNIX Copy Program

Who

Who Is

World Wide Web

X Display Manager Control Protocol

Local Ports and Protocols

Table A-8

lists the protocols, TCP ports, and UDP ports that the adaptive security appliance may open to process traffic destined to the adaptive security appliance. Unless you enable the features and services listed in

Table A-8 , the adaptive security appliance does

not

open any local protocols or any TCP or UDP ports. You must configure a feature or service for the adaptive security appliance to open the default listening protocol or port. In many cases you can configure ports other than the default port when you enable a feature or service.

Table A-8

Feature or Service

DHCP

Failover Control

HTTP

HTTPS

ICMP

IGMP

ISAKMP/IKE

IPSec (ESP)

Protocols and Ports Opened by Features and Services

IPSec over UDP

(NAT-T)

IPSec over UDP

(Cisco VPN 3000

Series compatible)

Protocol

UDP

108

TCP

TCP

1

2

UDP

50

UDP

UDP

Port Number

67,68

N/A

80

443

N/A

N/A

500

N/A

4500

10000

Comments

—

—

—

—

—

Protocol only open on destination IP address 224.0.0.1

Configurable.

—

—

Configurable.

A-14


OL-20339-01


ICMP Types

Table A-8 Protocols and Ports Opened by Features and Services (continued)

Feature or Service

IPSec over TCP

(CTCP)

NTP

OSPF

PIM

RIP

RIPv2

SNMP

SSH

Stateful Update

Telnet

VPN Individual User

Authentication Proxy

Protocol

TCP

UDP

89

103

UDP

UDP

UDP

TCP

105

TCP

VPN Load Balancing UDP

UDP

Port Number

—

123

N/A

N/A

520

520

161

22

N/A

23

9023

1645, 1646

Comments

No default port is used. You must specify the port number when configuring IPSec over TCP.

—

Protocol only open on destination IP address 224.0.0.5 and 224.0.0.6

Protocol only open on destination IP address 224.0.0.13

—

Port only open on destination IP address

224.0.0.9

Configurable.

—

—

—

Configurable.

Port accessible only over VPN tunnel.

ICMP Types

Table A-9 lists the ICMP type numbers and names that you can enter in adaptive security appliance

commands.

Table A-9 ICMP Types

9

10

11

12

13

14

4

5

6

8

ICMP Number

0

3

ICMP Name

echo-reply unreachable source-quench redirect alternate-address echo router-advertisement router-solicitation time-exceeded parameter-problem timestamp-request timestamp-reply

OL-20339-01


A-15

ICMP Types

Table A-9

17

18

31

32

ICMP Number

15

16

ICMP Types (continued)

ICMP Name

information-request information-reply mask-request mask-reply conversion-error mobile-redirect


A-16


OL-20339-01

A P P E N D I X

B

Configuring an External Server for Authorization and Authentication

This appendix describes how to configure an external LDAP, RADIUS, or TACACS+ server to support

AAA on the adaptive security appliance. Before you configure the adaptive security appliance to use an external server, you must configure the server with the correct adaptive security appliance authorization attributes and, from a subset of these attributes, assign specific permissions to individual users.

This appendix includes the following sections:

•

Understanding Policy Enforcement of Permissions and Attributes, page B-2

•

•

•

Configuring an External LDAP Server, page B-3

Configuring an External RADIUS Server, page B-30

Configuring an External TACACS+ Server, page B-39

OL-20339-01


B-1

Appendix B Configuring an External Server for Authorization and Authentication

Understanding Policy Enforcement of Permissions and Attributes

Understanding Policy Enforcement of Permissions and

Attributes

The adaptive security appliance supports several methods of applying user authorization attributes (also called user entitlements or permissions) to VPN connections. You can configure the adaptive security appliance to obtain user attributes from a Dynamic Access Policy (DAP) on the adaptive security appliance, from an external authentication and/or authorization AAA server (RADIUS or LDAP), from a group policy on the security appliance, or from all three.

If the security appliance receives attributes from all sources, the attributes are evaluated, merged, and applied to the user policy. If there are conflicts between attributes coming from the DAP, the AAA server, or the group policy, those attributes obtained from the DAP always take precedence.

The security appliance applies attributes in the following order (also illustrated in

Figure B-1

:

1.

2.

DAP attributes on the adaptive security appliance—Introduced in Version 8.0, take precedence over all others. If you set a bookmark/URL list in DAP, it overrides a bookmark/URL list set in the group policy.

User attributes on the AAA server—The server returns these after successful user authentication and/or authorization. Do not confuse these with attributes that are set for individual users in the local

AAA database on the adaptive security appliance (User Accounts in ASDM).

3.

4.

5.

Group policy configured on the adaptive security appliance—If a RADIUS server returns the value of the RADIUS CLASS attribute IETF-Class-25 (OU=<group-policy>) for the user, the adaptive security appliance places the user in the group policy of the same name and enforces any attributes in the group policy that are not returned by the server.

For LDAP servers, any attribute name can be used to set the group policy for the session. The LDAP attribute map you configure on the adaptive security appliance maps the LDAP attribute to the Cisco attribute IETF-Radius-Class.

Group policy assigned by the Connection Profile (called tunnel-group in CLI)—The Connection

Profile has the preliminary settings for the connection, and includes a default group policy applied to the user before authentication. All users connecting to the adaptive security appliance initially belong to this group which provides any attributes that are missing from the DAP, user attributes returned by the server, or the group policy assigned to the user.

Default group policy assigned by the adaptive security appliance (DfltGrpPolicy)—System default attributes provide any values that are missing from the DAP, user attributes, group policy, or connection profile.

B-2


OL-20339-01


Figure B-1 Policy Enforcement Flow

Configuring an External LDAP Server


The VPN 3000 Concentrator and the ASA/PIX 7.0 required a Cisco LDAP schema for authorization operations. Beginning with Version 7.1.x, the adaptive security appliance performs authentication

and

authorization, using the native LDAP schema, and the Cisco schema is no longer needed.

You configure authorization (permission policy) using an LDAP attribute map. For examples, see

Active Directory/LDAP VPN Remote Access Authorization Use Cases, page B-16

.

This section describes the structure, schema, and attributes of an LDAP server. It includes the following topics:

•

•

•

Organizing the Security Appliance for LDAP Operations, page B-3

Defining the Security Appliance LDAP Configuration, page B-6

Active Directory/LDAP VPN Remote Access Authorization Use Cases, page B-16

The specific steps of these processes vary, depending on which type of LDAP server you are using.

Note

For more information on the LDAP protocol, see RFCs 1777, 2251, and 2849.

Organizing the Security Appliance for LDAP Operations

This section describes how to perform searches within the LDAP hierarchy and authenticated binding to the LDAP server on the adaptive security appliance. It includes the following topics:

•

Searching the Hierarchy, page B-4

•

•

Binding the Security Appliance to the LDAP Server, page B-5

Login DN Example for Active Directory, page B-5

OL-20339-01


B-3



Your LDAP configuration should reflect the logical hierarchy of your organization. For example, suppose an employee at your company, Example Corporation, is named Terry. Terry works in the

Engineering group. Your LDAP hierarchy could have one or many levels. You might decide to set up a shallow, single-level hierarchy in which Terry is considered a member of Example Corporation. Or, you could set up a multi-level hierarchy in which Terry is considered to be a member of the department

Engineering, which is a member of an organizational unit called People, which is itself a member of

Example Corporation. See

Figure B-2 for an example of this multi-level hierarchy.

A multi-level hierarchy has more granularity, but a single level hierarchy is quicker to search.

Figure B-2 A Multi-Level LDAP Hierarchy

Example.com.com Enterprise LDAP Hierarchy

dc=ExampleCorp, dc=com

Root/Top

People

Equipment

OU=Organization Units

Engineering

Marketing HR

Groups/Departments

cn=terry cn=robin cn=bobbie cn=lynn

Users

Searching the Hierarchy

The adaptive security appliance lets you tailor the search within the LDAP hierarchy. You configure the following three fields on the adaptive security appliance to define where in the LDAP hierarchy your search begins, the extent, and the type of information it is looking for. Together these fields allow you to limit the search of the hierarchy to only the part of the tree that contains the user permissions.

•

LDAP Base DN defines where in the LDAP hierarchy the server should begin searching for user information when it receives an authorization request from the adaptive security appliance.

•

•

Search Scope defines the extent of the search in the LDAP hierarchy. The search proceeds this many levels in the hierarchy below the LDAP Base DN. You can choose to have the server search only the level immediately below, or it can search the entire subtree. A single level search is quicker, but a subtree search is more extensive.

Naming Attribute(s) defines the RDN that uniquely identifies an entry in the LDAP server. Common naming attributes can include cn (Common Name), sAMAccountName, and userPrincipalName.

Figure B-2 shows a possible LDAP hierarchy for Example Corporation. Given this hierarchy, you could

define your search in different ways. Table B-1

shows two possible search configurations.

In the first example configuration, when Terry establishes the IPSec tunnel with LDAP authorization required, the adaptive security appliance sends a search request to the LDAP server indicating it should search for Terry in the Engineering group. This search is quick.

In the second example configuration, the adaptive security appliance sends a search request indicating the server should search for Terry within Example Corporation. This search takes longer.

B-4


OL-20339-01



Table B-1 Example Search Configurations

# LDAP Base DN

1 group= Engineering,ou=People,dc=ExampleCorporation, dc=com

2 dc=ExampleCorporation,dc=com

Search

Scope

One Level

Subtree

Naming

Attribute Result

cn=Terry Quicker search cn=Terry Longer search

Binding the Security Appliance to the LDAP Server

Some LDAP servers (including the Microsoft Active Directory server) require the adaptive security appliance to establish a handshake via authenticated binding before they accept requests for any other

LDAP operations. The adaptive security appliance uses the Login Distinguished Name (DN) and Login

Password to establish trust (bind) with an LDAP server. The Login DN represents a user record in the

LDAP server that the administrator uses for binding.

When binding, the adaptive security appliance authenticates to the server using the Login DN and the

Login Password. When performing a Microsoft Active Directory read-only operation (such as for authentication, authorization, or group-search), the security appliance can bind with a Login DN with less privileges. For example, the Login DN can be a user whose AD "Member Of" designation is part of

Domain Users. For VPN password management operations, the Login DN needs elevated privileges and must be part of the Account Operators AD group.

An example of a Login DN includes: cn=Binduser1,ou=Admins,ou=Users,dc=company_A,dc=com

The security appliance supports:

•

•

•

•

Simple LDAP authentication with an unencrypted password on port 389

Secure LDAP (LDAP-S) on port 636

Simple Authentication and Security Layer (SASL) MD5

SASL Kerberos.

The security appliance does not support anonymous authentication.

Note

As an LDAP client, the adaptive security appliance does not support sending anonymous binds or requests.

Login DN Example for Active Directory

The Login DN is a username on the LDAP server that the adaptive security appliance uses to establish a trust between itself (the LDAP client) and the LDAP server during the Bind exchange, before a user search can take place.

For VPN authentication/authorization operations, and beginning with version 8.0.4 for retrieval of AD

Groups, (which are read operations only when password-management changes are not required), the you can use the Login DN with fewer privileges. For example, the Login DN can be a user who is a memberOf the Domain Users group.

For VPN password-management changes, the Login DN must have Account Operators privileges.

In either of these cases, Super-user level privileges are not required for the Login/Bind DN. Refer to your

LDAP Administrator guide for specific Login DN requirements.

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B-5



Defining the Security Appliance LDAP Configuration

This section describes how to define the LDAP AV-pair attribute syntax. It includes the following topics:

•

Supported Cisco Attributes for LDAP Authorization, page B-6

•

•

Cisco AV Pair Attribute Syntax, page B-13

Cisco AV Pairs ACL Examples, page B-15

Note

The adaptive security appliance enforces the LDAP attributes based on attribute name, not numeric ID.

RADIUS attributes, on the other hand, are enforced by numeric ID, not by name.

Authorization refers to the process of enforcing permissions or attributes. An LDAP server defined as an authentication or authorization server will enforce permissions or attributes if they are configured.

For software Version 7.0, LDAP attributes include the cVPN3000 prefix. For Version 7.1 and later, this prefix was removed.

Supported Cisco Attributes for LDAP Authorization

This section provides a complete list of attributes (

Table B-2 ) for the ASA 5500, VPN 3000, and PIX

500 series adaptive security appliances. The table includes attribute support information for the VPN

3000 and PIX 500 series to assist you configure networks with a mixture of these adaptive security appliances.

Table B-2 Security Appliance Supported Cisco Attributes for LDAP Authorization

Attribute Name/

Access-Hours

Allow-Network-Extension- Mode

Authenticated-User-Idle- Timeout

Authorization-Required

Authorization-Type

Banner1

Banner2

VPN 3000 ASA PIX

Y Y Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Syntax/

Type

Single or

Multi-Valued

String Single

Possible Values

Name of the time-range

(for example, Business-Hours)

Boolean Single

Integer

Integer

Integer

Single

Single

Single

0 = Disabled

1 = Enabled

1 - 35791394 minutes

0 = No

1 = Yes

0 = None

1 = RADIUS

2 = LDAP

String Single

String Single

Banner string for clientless and client SSL VPN, and IPSec clients.

Banner string for clientless and client SSL VPN, and IPSec clients.

B-6


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Table B-2 Security Appliance Supported Cisco Attributes for LDAP Authorization (continued)

Attribute Name/

Cisco-AV-Pair

Cisco-IP-Phone-Bypass

Cisco-LEAP-Bypass

Client-Intercept-DHCP-

Configure-Msg

Client-Type-Version-Limiting

Confidence-Interval

DHCP-Network-Scope

DN-Field

Firewall-ACL-In

Firewall-ACL-Out

Group-Policy

IE-Proxy-Bypass-Local

IE-Proxy-Exception-List

Y

Y

Y

Y

Y

Y

Y


Y Y Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Syntax/

Type

Single or

Multi-Valued

String Multi

Possible Values

An octet string in the following format:

Integer

Integer

Boolean Single

String

Integer

String

String

String

String

String

Single

Single

Single

Single

Single

Single

Boolean Single

String

Single

Single

Single

Single

[Prefix] [Action] [Protocol]

[Source] [Source Wildcard Mask]

[Destination] [Destination Wildcard

Mask] [Established] [Log]

[Operator] [Port]

For more information, see “

Cisco

AV Pair Attribute Syntax .”

0 = Disabled

1 = Enabled

0 = Disabled

1 = Enabled

0 = Disabled

1 = Enabled

IPSec VPN client version number string

10 - 300 seconds

IP address

Possible values: UID, OU, O, CN,

L, SP, C, EA, T, N, GN, SN, I,

GENQ, DNQ, SER, use-entire-name.

Access list ID

Access list ID

Sets the group policy for the remote access VPN session. For version 8.2 and later, use this attribute instead of

IETF-Radius-Class. You can use one of the three following formats:

•

<group policy name>

•

•

OU=<group policy name>

OU=<group policy name>;

0=Disabled

1=Enabled

A list of DNS domains. Entries must be separated by the new line character sequence (\n).

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B-7




Attribute Name/

IE-Proxy-Method

IE-Proxy-Server

IETF-Radius-Class

IETF-Radius-Filter-Id

IETF-Radius-Framed-IP-Address Y

IETF-Radius-Framed-IP-Netmask Y

IETF-Radius-Idle-Timeout Y

IETF-Radius-Service-Type Y

IETF-Radius-Session-Timeout

IKE-Keep-Alives

IPSec-Allow-Passwd-Store

IPSec-Authentication

IPSec-Auth-On-Rekey

IPSec-Backup-Server-List

Y

Y


Y Y Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Syntax/

Type

Single or

Multi-Valued

Integer Single

Possible Values

1 = Do not modify proxy settings

2 = Do not use proxy

3 = Auto detect

4 = Use adaptive security appliance setting

Integer Single

Single

IP Address

Sets the group policy for the remote access VPN session. For version 8.2 and later, we recommend that you use the Group-Policy attribute. You can use one of the three following formats:

•

<group policy name>

String

String

Integer

Single

String Single

Integer Single

Integer Single

Single

Boolean Single

Boolean Single

Integer

Boolean Single

String

Single

Single

Single

•

•


OU=<group policy name>; access list name that is defined on the adaptive security appliance

An IP address

An IP address mask seconds

1 = Login

2 = Framed

6 = Administrative

7 = NAS Prompt seconds

0 = Disabled

1 = Enabled

0 = Disabled

1 = Enabled

0 = None

1 = RADIUS

2 = LDAP (authorization only)

3 = NT Domain

4 = SDI (RSA)

5 = Internal

6 = RADIUS with Expiry

7 = Kerberos/Active Directory

0 = Disabled

1 = Enabled

Server Addresses (space delimited)

B-8


OL-20339-01




Attribute Name/

IPSec-Backup-Servers

IPSec-Client-Firewall-Filter-

Optional

IPSec-Default-Domain

IPSec-Over-UDP-Port

IPSec-Required-Client-Firewall-

Capability


Y Y Y

IPSec-Client-Firewall-Filter- Name Y

IPSec-Extended-Auth-On-Rekey

IPSec-IKE-Peer-ID-Check

IPSec-IP-Compression

IPSec-Mode-Config

IPSec-Over-UDP

IPSec-Sec-Association

IPSec-Split-DNS-Names

IPSec-Split-Tunneling-Policy

IPSec-Split-Tunnel-List

IPSec-Tunnel-Type

IPSec-User-Group-Lock

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Syntax/

Type

Single or

Multi-Valued

String Single

Possible Values

1 = Use Client-Configured list

2 = Disabled and clear client list

3 = Use Backup Server list

String Single

Integer Single

Specifies the name of the filter to be pushed to the client as firewall policy.

0 = Required

1 = Optional

String Single Specifies the single default domain name to send to the client (1 - 255 characters).

String Single

Integer Single

Integer Single

Boolean Single

Boolean Single

1 = Required

2 = If supported by peer certificate

3 = Do not check

0 = Disabled

1 = Enabled

0 = Disabled

1 = Enabled

0 = Disabled

1 = Enabled

Integer Single

Integer Single

String

String

Integer

String

Integer

Single

Single

Single

Single

Single

Boolean Single

4001 - 49151; default = 10000

0 = None

1 = Policy defined by remote FW

Are-You-There (AYT)

2 = Policy pushed CPP

4 = Policy from server

Name of the security association

Specifies the list of secondary domain names to send to the client

(1 - 255 characters).

0 = Tunnel everything

1 = Split tunneling

2 = Local LAN permitted

Specifies the name of the network or access list that describes the split tunnel inclusion list.

1 = LAN-to-LAN

2 = Remote access

0 = Disabled

1 = Enabled

OL-20339-01


B-9



Table B-2

Attribute Name/

PFS-Required

Primary-DNS

Primary-WINS

Security Appliance Supported Cisco Attributes for LDAP Authorization (continued)

L2TP-Encryption

L2TP-MPPC-Compression

MS-Client-Subnet-Mask

Port-Forwarding-Name

PPTP-Encryption

PPTP-MPPC-Compression

Privilege-Level

Required-Client-

Firewall-Vendor-Code


Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Syntax/

Type

Single or

Multi-Valued

Integer Single

Possible Values

Bitmap:

Integer

String

Single

Boolean Single

String

Integer

Integer

String

String

Single

Single

Single

Single

Single

Single

1 = Encryption required

2 = 40 bit

4 = 128 bits

8 = Stateless-Req

15 = 40/128-Encr/Stateless-Req

0 = Disabled

1 = Enabled

An IP address

0 = No

1 = Yes

Name string (for example,

“Corporate-Apps”)

Bitmap:


2 = 40 bits

4 = 128 bits

8 = Stateless-Required

Example:

15 = 40/128-Encr/Stateless-Req

0 = Disabled

1 = Enabled

An IP address

An IP address

Y Y Y Integer Single

Required-Client-Firewall-

Description

Y Y Y String Single

1 = Cisco Systems (with Cisco

Integrated Client)

2 = Zone Labs

3 = NetworkICE

4 = Sygate


Intrusion Prevention Security

Agent)

String

B-10


OL-20339-01



Table B-2

Attribute Name/

Product-Code

Secondary-DNS

Secondary-WINS

SEP-Card-Assignment

Simultaneous-Logins

Strip-Realm


Required-Client-Firewall-

Require-HW-Client-Auth

Require-Individual-User-Auth

TACACS-Authtype

TACACS-Privilege-Level

Tunnel-Group-Lock

Tunneling-Protocols

Use-Client-Address

User-Auth-Server-Name

User-Auth-Server-Port

User-Auth-Server-Secret

WebVPN-ACL-Filters

Y

Y

Y


Y Y Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Syntax/

Type

Single or

Multi-Valued

Integer Single

Possible Values

Cisco Systems Products:

1 = Cisco Intrusion Prevention

Security Agent or Cisco

Integrated Client (CIC)

Zone Labs Products:

Boolean Single

Integer

String

String

Single

Single

Single

Integer Single

Integer Single

Boolean Single

1 = Zone Alarm

2 = Zone AlarmPro

3 = Zone Labs Integrity

NetworkICE Product:

1 = BlackIce Defender/Agent

Sygate Products:

1 = Personal Firewall

2 = Personal Firewall Pro

3 = Security Agent

0 = Disabled

1 = Enabled

0 = Disabled

1 = Enabled

An IP address

An IP address

Not used

0-2147483647

0 = Disabled

1 = Enabled

Interger Single

Interger Single

String Single

Integer Single

Boolean Single

String

Integer

String

String

Single

Single

Single

Single

Name of the tunnel group or “none”

1 = PPTP

2 = L2TP

4 = IPSec

8 = L2TP/IPSec

16 = WebVPN.

8 and 4 are mutually exclusive

(0 - 11, 16 - 27 are legal values)

0 = Disabled

1 = Enabled

IP address or hostname

Port number for server protocol

Server password

Webtype Access-List name


OL-20339-01 B-11



Table B-2

Attribute Name/


WebVPN-Apply-ACL-Enable

WebVPN-Citrix-Support-Enable

WebVPN-Enable-functions

WebVPN-Exchange-Server-

Address

WebVPN-Exchange-Server-

NETBIOS-Name

WebVPN-File-Access-Enable


Y Y

Y Y

Syntax/

Type

Single or

Multi-Valued

Integer Single

Possible Values

0 = Disabled

1 = Enabled

Integer

Integer

String

Single

Single

Single

With version 8.0 and later, this attribute is not required.

0 = Disabled

1 = Enabled

With version 8.0 and later, this attribute is not required.

Not used - deprecated


Y Y

String

Integer

Single

Single


WebVPN-File-Server-Browsing-

Enable

WebVPN-File-Server-Entry-

Enable

WebVPN-Forwarded-Ports

WebVPN-Homepage

WebVPN-Macro-Substitution-

Value1

WebVPN-Macro-Substitution-

Value2

WebVPN-Port-Forwarding-

Auto-Download-Enable

Y

WebVPN-Port-Forwarding- Enable Y


Exchange-Proxy-Enable

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Integer

Integer

String

String

String

String

Integer

Integer

Integer

Single

Single

Single

Single

Single

Single

Single

Single

Single

0 = Disabled

1 = Enabled

0 = Disabled

1 = Enabled

0 = Disabled

1 = Enabled

Port-Forward list name

A URL such as http://example-portal.com.

See

SSL VPN Deployment Guide

for examples and use cases at this URL: http://supportwiki.cisco.com/View

Wiki/index.php/Cisco_ASA_5500_

SSL_VPN_Deployment_Guide%2

C_Version_8.x

See


for examples and use cases at this URL: http://supportwiki.cisco.com/View

Wiki/index.php/Cisco_ASA_5500_

SSL_VPN_Deployment_Guide%2

C_Version_8.x

0 = Disabled

1 = Enabled

0 = Disabled

1 = Enabled

0 = Disabled

1 = Enabled

B-12


OL-20339-01



Table B-2

Attribute Name/



HTTP-Proxy-Enable

WebVPN-Single-Sign-On-

Server-Name

WebVPN-SVC-Client-DPD

WebVPN-SVC-Compression

WebVPN-SVC-Enable

WebVPN-SVC-Gateway-DPD

WebVPN-SVC-Keepalive

WebVPN-SVC-Keep-Enable

WebVPN-SVC-Rekey-Method

WebVPN-SVC-Rekey-Period

WebVPN-SVC-Required-Enable

WebVPN-URL-Entry-Enable

WebVPN-URL-List


Y Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Syntax/

Type

Single or

Multi-Valued

Integer Single

Possible Values

String Single

0 = Disabled

1 = Enabled

Name of the SSO Server (1 - 31 characters).

Integer Single

Integer

Integer

Single

Single

0 = Disabled n = Dead Peer Detection value in seconds (30 - 3600)

0 = None

1 = Deflate Compression

0 = Disabled

1 = Enabled

Integer Single

Integer

Integer

Integer

Single

Single

Single

0 = Disabled n = Dead Peer Detection value in seconds (30 - 3600)

0 = Disabled n = Keepalive value in seconds (15 -

600)

0 = Disabled

1 = Enabled

0 = None

1 = SSL

2 = New tunnel

3 = Any (sets to SSL)

Integer Single

Integer

Integer

String

Single

Single

Single

0 = Disabled n = Retry period in minutes

(4 - 10080)

0 = Disabled

1 = Enabled

0 = Disabled

1 = Enabled

URL-list name

Cisco AV Pair Attribute Syntax

The Cisco Attribute Value (AV) pair (ID# 26/9/1) can be used to enforce access lists from a Radius server

(like Cisco ACS), or from an LDAP server via an ldap-attribute-map.

The syntax of each Cisco-AV-Pair rule is as follows:

[Prefix] [Action] [Protocol] [Source] [Source Wildcard Mask] [Destination] [Destination Wildcard

Mask] [Established] [Log] [Operator] [Port]

Table B-3 describes the syntax rules.

OL-20339-01


B-13



Table B-3 AV-Pair Attribute Syntax Rules

Field

Prefix

Action

Protocol

Description

A unique identifier for the AV pair. For example: ip:inacl#1=

(for standard access lists) or webvpn:inacl#

(for clientless SSL VPN access lists). This field only appears when the filter has been sent as an AV pair.

Action to perform if rule matches: deny, permit.

Number or name of an IP protocol. Either an integer in the range 0 - 255 or one of the following keywords: icmp, igmp, ip, tcp, udp.

Source

Source Wildcard Mask The wildcard mask that applies to the source address. This field does not apply to Clientless SSL VPN because the adaptive security appliance plays the role of the source/proxy

Destination

Network or host that sends the packet. Specify it as an IP address, a hostname, or the keyword “any.” If using an IP address, the source wildcard mask must follow. This field does not apply to Clientless SSL VPN because the adaptive security appliance plays the role of the source/proxy

Network or host that receives the packet. Specify as an IP address, a hostname, or the keyword “any.” If using an IP address, the source wildcard mask must follow.

The wildcard mask that applies to the destination address.

Destination Wildcard

Mask

Log Generates a FILTER log message. You must use this keyword to generate events of severity level 9.

Operator

Port

Logic operators: greater than, less than, equal to, not equal to.

The number of a TCP or UDP port in the range 0 - 65535.

B-14


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Cisco AV Pairs ACL Examples

Table B-4 shows examples of Cisco AV pairs and describes the allow or deny actions that result.

Note

Each ACL # in inacl#

must be unique. However, they do not need to be sequential (i.e. 1, 2, 3, 4). For example, they could be 5, 45, 135.

Table B-4 Examples of Cisco AV Pairs and their Permitting or Denying Action

Cisco AV Pair Example

ip:inacl#1=deny ip 10.155.10.0 0.0.0.255 10.159.2.0

0.0.0.255 log ip:inacl#2=permit TCP any host 10.160.0.1 eq 80 log webvpn:inacl#1=permit url http://www.website.com

webvpn:inacl#2=deny url smtp://server webvpn:inacl#3=permit url cifs://server/share webvpn:inacl#1=permit tcp 10.86.1.2 eq 2222 log webvpn:inacl#2=deny tcp 10.86.1.2 eq 2323 log webvpn:inacl#1=permit url ssh://10.86.1.2 webvpn:inacl#35=permit tcp 10.86.1.5 eq 22 log webvpn:inacl#48=deny url telnet://10.86.1.2 webvpn:inacl#100=deny tcp 10.86.1.6 eq 23

Permitting or Denying Action

Allows IP traffic between the two hosts using full tunnel

IPsec or SSL VPN client.

Allows TCP traffic from all hosts to the specific host on port

80 only using full tunnel IPsec or SSL VPN client.

Allows clientless traffic to the URL specified, denies smtp traffic to a specific server, and allows file share access (CIFS) to the specified server.

Denies telnet and permits SSH on non-default ports 2323 and

2222, respectively.

Allows SSH to default port 22 and 23, respectively. For this example, we assume you are using telnet/ssh java plugins enforced by these ACLs.

URL Types supported in ACLs

The URL may be a partial URL, contain wildcards for the server, or contain a port.

The following URL types are supported: any All URLs cifs:// citrix:// citrixs:// ftp:// http:// https:// ica:// imap4:// nfs:// pop3:// post:// rdp:// sametime:// telnet:// smart-tunnel:// tn3270:// smtp:// ssh:// tn5250:// vnc://

OL-20339-01

Note

The URLs listed above appear in CLI or ASDM menus based on whether the associated plugin is enabled.

Guidelines for using Cisco-AV Pairs (ACLs)

•

Use Cisco-AV pair entries with the ip:inacl# prefix to enforce access lists for remote IPSec and SSL

VPN Client (SVC) tunnels.

•

Use Cisco-AV pair entries with the webvpn:inacl# prefix to enforce access lists for SSL VPN clientless (browser-mode) tunnels.

•

For Webtype ACLs, you don’t specify the source because the adaptive security appliance is the source.


B-15



Table B-5

lists the tokens for the Cisco-AV-pair attribute:

Security Appliance-Supported Tokens Table B-5

Token

ip:inacl#

Num

=

Syntax Field Description

N/A (Identifier) (Where

Num

is a unique integer.) Starts all AV pair access control lists. Enforces access lists for remote IPSec and SSL VPN (SVC) tunnels.

webvpn:inacl#

Num

= N/A (Identifier) (Where

Num

is a unique integer.) Starts all clientless SSL AV pair access control lists. Enforces access lists for clientless (browser-mode) tunnels.

deny Action Denies action. (Default) permit icmp

1

IP

0

TCP

6

UDP

17 any host log

Action

Protocol

Protocol

Protocol

Protocol

Protocol

Protocol

Protocol

Protocol

Hostname

Hostname

Log

Allows action.

Internet Control Message Protocol (ICMP)

Internet Control Message Protocol (ICMP)

Internet Protocol (IP)

Internet Protocol (IP)

Transmission Control Protocol (TCP)

Transmission Control Protocol (TCP)

User Datagram Protocol (UDP)

User Datagram Protocol (UDP)

Rule applies to any host.

Any alpha-numeric string that denotes a hostname.

When the event is hit, a filter log message appears. (Same as permit and log or deny and log.) lt gt eq neq range

Operator

Operator

Operator

Operator

Operator

Less than value

Greater than value

Equal to value

Not equal to value

Inclusive range. Should be followed by two values.

Active Directory/LDAP VPN Remote Access Authorization Use Cases

This section presents example procedures for configuring authentication and authorization on the adaptive security appliance using the Microsoft Active Directory server. It includes the following use cases:

•

User-Based Attributes Policy Enforcement, page B-18

•

•

•

Placing LDAP users in a specific Group-Policy, page B-20

Enforcing Static IP Address Assignment for AnyConnect Tunnels, page B-22

Enforcing Dial-in Allow or Deny Access, page B-25

Enforcing Logon Hours and Time-of-Day Rules, page B-28

•

Other configuration examples available on Cisco.com include the following TechNotes:

•

ASA/PIX: Mapping VPN Clients to VPN Group Policies Through LDAP Configuration Example

at:

B-16


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•

http://www.cisco.com/en/US/products/ps6120/products_configuration_example09186a008089149 d.shtml

PIX/ASA 8.0: Use LDAP Authentication to Assign a Group Policy at Login

at: http://www.cisco.com/en/US/partner/products/ps6120/products_configuration_example09186a008

08d1a7c.shtml

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User-Based Attributes Policy Enforcement

Any standard LDAP attribute can be mapped to a well-known Vendor Specific Attribute (VSA)

Likewise, one or more LDAP attribute(s) can be mapped to one or more Cisco LDAP attributes.

In this use case we configure the adaptive security appliance to enforce a simple banner for a user configured on an AD LDAP server. For this case, on the server, we use the Office field in the General tab to enter the banner text. This field uses the attribute named

physicalDeliveryOfficeName

. On the adaptive security appliance, we create an attribute map that maps


to the

Cisco attribute

Banner1

. During authentication, the adaptive security appliance retrieves the value of physicalDeliveryOfficeName from the server, maps the value to the Cisco attribute Banner1, and displays the banner to the user.

This case applies to any connection type, including the IPSec VPN client, AnyConnect SSL VPN client, or clientless SSL VPN. For the purposes of this case, User1 is connecting through a clientless SSL VPN connection.

Step 1

Configure the attributes for a user on the AD/LDAP Server.

Right-click a user. The properties window displays (

Figure B-3 ). Click the General tab and enter some

banner text in the Office field. The Office field uses the AD/LDAP attribute


.

Figure B-3 Figure 3 LDAP User configuration

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Step 2

Step 3

Step 4

Create an LDAP attribute map on the adaptive security appliance:

The following example creates the map

Banner

, and maps the AD/LDAP attribute


to the Cisco attribute

Banner1

: hostname(config)#

ldap attribute-map Banner

hostname(config-ldap-attribute-map)#

map-name physicalDeliveryOfficeName Banner1

Associate the LDAP attribute map to the AAA server.

The following example enters the aaa server host configuration more for the host

3.3.3.4

, in the AAA server group

MS_LDAP

, and associates the attribute map

Banner

that you created in step 2: hostname(config)#

aaa-server MS_LDAP host 3.3.3.4

hostname(config-aaa-server-host)#

ldap-attribute-map Banner

Test the banner enforcement.

This example shows a clientless SSL connection and the banner enforced through the attribute map after the user authenticates (

Figure B-4

).

Figure B-4 Banner Displayed

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B-19



Placing LDAP users in a specific Group-Policy

In this case we authenticate User1 on the AD LDAP server to a specific group policy on the adaptive security appliance. On the server, we use the

Department

field of the Organization tab to enter the name of the group policy. Then we create an attribute map and map Department to the Cisco attribute

IETF-Radius-Class

. During authentication, the adaptive security appliance retrieves the value of

Department from the server, maps the value to the IETF-Radius-Class, and places User1 in the group policy.

This case applies to any connection type, including the IPSec VPN client, AnyConnect SSL VPN client, or clientless SSL VPN. For the purposes of this case, user1 is connecting through a clientless SSL VPN connection.

Step 1

Configure the attributes for the user on the AD LDAP Server.

Right-click the user. The Properties window displays (

Figure B-5 ). Click the Organization tab and enter

Group-Policy-1

in the Department field.

Figure B-5 AD LDAP Department attribute

Step 2

Step 3

Define an attribute map for the LDAP configuration shown in

Step 1 .

In this case we map the AD attribute Department to the Cisco attribute IETF-Radius-Class. For example: hostname(config)#

ldap attribute-map group_policy


map-name Department IETF-Radius-Class


The following example enters the aaa server host configuration mode for the host

3.3.3.4


MS_LDAP


group_policy




ldap-attribute-map group_policy

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Step 4

Step 5

Add the new group-policy on the adaptive security appliance and configure the required policy attributes that will be assigned to the user. For this case, we created the Group-policy-1, the name entered in the

Department field on the server: hostname(config)#

group-policy Group-policy-1 external server-group LDAP_demo

hostname(config-aaa-server-group)#

Establish the VPN connection as the user would, and verify that the session inherits the attributes from

Group-Policy1 (and any other applicable attributes from the default group-policy)

You can monitor the communication between the adaptive security appliance and the server by enabling the

debug ldap 255

command from privileged EXEC mode. Below is sample output of this command.

The output has been edited to provide the key messages:

[29] Authentication successful for user1 to 3.3.3.4

[29] Retrieving user attributes from server 3.3.3.4

[29] Retrieved Attributes:

[29] department: value = Group-Policy-1

[29] mapped to IETF-Radius-Class: value = Group-Policy-1

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Enforcing Static IP Address Assignment for AnyConnect Tunnels

In this case we configure the AnyConnect client user

Web1

to receive a static IP Address. We enter the address in the

Assign Static IP Address

field of the Dialin tab on the AD LDAP server. This field uses the

msRADIUSFramedIPAddress

attribute. We create an attribute map that maps it to the Cisco attribute

IETF-Radius-Framed-IP-Address

.

During authentication, the adaptive security appliance retrieves the value of msRADIUSFramedIPAddress from the server, maps the value to the Cisco attribute

IETF-Radius-Framed-IP-Address, and provides the static address to User1 .

This case applies to full-tunnel clients, including the IPSec client and the SSL VPN clients (AnyConnect client 2.x and the legacy SSL VPN client).

Step 1

Configure the user attributes on the AD LDAP server.

Right-click on the user name. The Properties window displays (

Figure B-6

). Click the Dialin tab, check

Assign Static IP Address

, and enter an IP address. For this case we use 3.3.3.233.

Figure B-6 Assign Static IP Address

Step 2

Create an attribute map for the LDAP configuration shown in

Step 1 .

In this case we map the AD attribute

msRADIUSFrameIPAddress

used by the Static Address field to the

Cisco attribute

IETF-Radius-Framed-IP-Address

.

For example: hostname(config)#

ldap attribute-map static_address


map-name msRADIUSFrameIPAddress

IETF-Radius-Framed-IP-Address

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Step 3

Step 4



3.3.3.4


MS_LDAP


static_address




ldap-attribute-map static_address

Verify the

vpn-address-assigment

command is configured to specify aaa by viewing this part of the configuration with the

show run all vpn-addr-assign command

: vpn-addr-assign aaa hostname(config)#

show run all vpn-addr-assign

vpn-addr-assign aaa

<<<< ensure this configured

.

no vpn-addr-assign dhcp vpn-addr-assign local hostname(config)#

Step 5

Establish a connection to the adaptive security appliance with the AnyConnect client. Observe the following:

•

The banner is received in the same sequence as a clientless connection ( Figure B-7 ).

•

The user receives the IP address configured on the server and mapped to the adaptive security

appliance ( Figure B-8 ).

Figure B-7 Verify the Banner for the AnyConnect Session

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B-23


Figure B-8


AnyConnect Session Established

You can use the

show vpn-sessiondb svc

command to view the session details and verify the address assigned: hostname#

show vpn-sessiondb svc

Session Type: SVC

Username : web1 Index : 31

Assigned IP : 3.3.3.233 Public IP : 10.86.181.70

Protocol : Clientless SSL-Tunnel DTLS-Tunnel

Encryption : RC4 AES128 Hashing : SHA1

Bytes Tx : 304140 Bytes Rx : 470506

Group Policy : VPN_User_Group Tunnel Group : UseCase3_TunnelGroup

Login Time : 11:13:05 UTC Tue Aug 28 2007

Duration : 0h:01m:48s

NAC Result : Unknown

VLAN Mapping : N/A VLAN : none

BXB-ASA5540#

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Enforcing Dial-in Allow or Deny Access

In this case, we create an LDAP attribute map that specifies the tunneling protocols allowed by the user.

We map the Allow Access and Deny Access settings on the Dialin tab to the Cisco attribute

Tunneling-Protocols. The Cisco Tunneling-Protocols supports the bit-map values shown in Table B-6

:

Table B-6 Bitmap Values for Cisco Tunneling-Protocol Attribute

Value

1

2

4

1

8

2

16

32

Tunneling Protocol

PPTP

L2TP

IPSec

L2TP/IPSEC clientless SSL

SSL Client—AnyConnect or legacy SSL VPN client

1.

IPSec and L2TP over IPSec are not supported simultaneously. Therefore, the values 4 and 8 are mutually exclusive.

2.

See note 1.

Using this attribute, we create an Allow Access (TRUE) or a Deny Access (FALSE) condition for the protocols and enforce what method the user is allowed access with.

For this simplified example, by mapping the tunnel-protocol IPSec (4), we can create an allow (true) condition for the IPSec Client. We also map WebVPN (16) and SVC/AC (32) which is mapped as value of 48 (16+32) and create a deny (false) condition. This allows the user to connect to the adaptive security appliance using IPSec, but any attempt to connect using clientless SSL or the AnyConnect client is denied.

Another example of enforcing Dial-in Allow Acess or Deny Access can be found in the Tech Note

ASA/PIX: Mapping VPN Clients to VPN Group Policies Through LDAP Configuration Example,

at this

URL: http://www.cisco.com/en/US/products/ps6120/products_configuration_example09186a008089149 d.shtml

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B-25



Step 1


Right-click on the user. The Properties window displays. Click the Dial-in tab. Select

Allow Access

(

Figure B-9

).

Figure B-9 AD-LDAP user1 - Allow access

Note

If you select the third option "Control access through the Remote Access Policy", then a value is not returned from the server, and the permissions that are enforced are based on the internal group policy settings of the adaptive security appliance.

Step 2

Step 3

Create an attribute map to allow both an IPSec and AnyConnect connection, but deny a clientless SSL connection.

In this case we create the map

tunneling_protocols

, and map the AD attribute

msNPAllowDialin

used by the Allow Access setting to the Cisco attribute

Tunneling-Protocols

using the

map-name

command, and add map values with the

map-value

command,


ldap attribute-map tunneling_protocols


map-name msNPAllowDialin Tunneling-Protocols


map-value msNPAllowDialin FALSE 48


map-value msNPAllowDialin TRUE 4



3.3.3.4


MS_LDAP


tunneling_protocols




ldap-attribute-map tunneling_protocols

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Step 4

Verify the attribute map works as configured.

Using a PC as a remote user would, attempt connections using clientless SSL, the AnyConnect client, and the IPSec client. The clientless and AnyConnect connections should fail and the user should be informed that an unauthorized connection mechanism was the reason for the failed connection. The

IPSec client should connect because IPSec is an allowed tunneling protocol according to attribute map.

Figure B-10 Login Denied Message for Clientless User

Figure B-11 Login Denied Message for AnyConnect Client User.

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B-27



Enforcing Logon Hours and Time-of-Day Rules

In this use case we configure and enforce the hours that a clientless SSL user is allowed to access the network. A good example of this is when you want to allow a business partner access to the network only during normal business hours.

For this case, on the AD server, we use the

Office

field to enter the name of the partner. This field uses the


attribute. Then we create an attribute map on the adaptive security appliance to map that attribute to the Cisco attribute

Access-Hours.

During authentication, the adaptive security appliance retrieves the value of physicalDeliveryOfficeName

(

the Office field

)

and maps it to

Access-Hours.

Step 1


Select the user. Right click on Properties. The Properties window displays ( Figure B-12 ). For this case,

we use the Office field of the General tab:

Figure B-12 Active Directory - Time-range

Step 2

Step 3

Create an attribute map.

In this case we create the attribute map access_hours and map the AD attribute


used by the Office field to the Cisco attribute

Access-Hours

.


ldap attribute-map access_hours


map-name physicalDeliveryOfficeName Access-Hours



3.3.3.4


MS_LDAP


access_hours



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Step 4


ldap-attribute-map access_hours

Configure time ranges for each value allowed on the server. In this case, we entered Partner in the Office field for User1. Therefore, there must be a time range configured for Partner. The following example configures Partner access hours from 9am to 5pm Monday through Friday: hostname(config)#

time-range Partner

hostname(config-time-range)#

periodic weekdays 09:00 to 17:00

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B-29


Configuring an External RADIUS Server


This section presents an overview of the RADIUS configuration procedure and defines the Cisco

RADIUS attributes. It includes the following topics:

•

Reviewing the RADIUS Configuration Procedure, page B-30

•

•

Security Appliance RADIUS Authorization Attributes, page B-30

Security Appliance IETF RADIUS Authorization Attributes, page B-38

Reviewing the RADIUS Configuration Procedure

This section describes the RADIUS configuration steps required to support authentication and authorization of the adaptive security appliance users. Follow these steps to set up the RADIUS server to inter operate with the adaptive security appliance.

Step 1

Step 2

Load the adaptive security appliance attributes into the RADIUS server. The method you use to load the attributes depends on which type of RADIUS server you are using:

•

If you are using Cisco ACS: the server already has these attributes integrated. You can skip this step.

•

•

If you are using a FUNK RADIUS server: Cisco supplies a dictionary file that contains all the adaptive security appliance attributes. Obtain this dictionary file, cisco3k.dct

, from Software

Center on CCO or from the adaptive security appliance CD-ROM. Load the dictionary file on your server.

For other vendors’ RADIUS servers (for example, Microsoft Internet Authentication Service): you must manually define each adaptive security appliance attribute. To define an attribute, use the attribute name or number, type, value, and vendor code (3076). For a list of adaptive security

appliance RADIUS authorization attributes and values, see Table B-7

.

Set up the users or groups with the permissions and attributes to send during IPSec or SSL tunnel establishment.

Security Appliance RADIUS Authorization Attributes

Authorization refers to the process of enforcing permissions or attributes. A RADIUS server defined as an authentication server enforces permissions or attributes if they are configured.

Table B-7

lists all the possible adaptive security appliance supported RADIUS attributes that can be used for user authorization.

Note

RADIUS attribute names do not contain the cVPN3000 prefix. Cisco Secure ACS 4.x supports this new nomenclature, but attribute names in pre-4.0 ACS releases still include the cVPN3000 prefix. The appliances enforce the RADIUS attributes based on attribute numeric ID, not attribute name. LDAP attributes are enforced by their name, not by the ID.

B-30


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Table B-7

Attribute Name

Access-Hours

Simultaneous-Logins

Primary-DNS

Secondary-DNS

Primary-WINS

Secondary-WINS

SEP-Card-Assignment

Tunneling-Protocols

IPSec-Sec-Association

IPSec-Authentication

Banner1

Security Appliance Supported RADIUS Attributes and Values

IPSec-Allow-Passwd-Store

Use-Client-Address

PPTP-Encryption

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

VPN

3000 ASA PIX

Y Y Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Attr.

#

1

Syntax/

Type

Single or

Multi-

Valued Description or Value

String Single Name of the time range, for example, Business-hours

2

5

6

7

Integer

String

String

String

Single

Single

Single

Single

An integer 0 to 2147483647 address

An IP address

An IP address

8

9

String

Integer

Single

Single

An IP address

Not used

11 Integer Single 1 = PPTP

2 = L2TP

4 = IPSec

8 = L2TP/IPSec

16 = WebVPN

4 and 8 are mutually exclusive;

0-11 and 16-27 are legal values.

12 String Single Name of the security association

13 Integer Single 0 = None

1 = RADIUS

2 = LDAP (authorization only)

3 = NT Domain

4 = SDI

5 = Internal

6 = RADIUS with Expiry

7 = Kerberos/Active Directory

15 String Single Banner string

16 Boolean Single 0 = Disabled

1 = Enabled


1 = Enabled

20 Integer Single Bitmap:


2 = 40 bits

4 = 128 bits

8 = Stateless-Required

15= 40/128-Encr/Stateless-Req

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B-31



Table B-7

Attribute Name

L2TP-Encryption

Group-Policy

IPSec-Split-Tunnel-List

IPSec-Default-Domain

IPSec-Split-DNS-Names

IPSec-Tunnel-Type

IPSec-Mode-Config

IPSec-User-Group-Lock

IPSec-Over-UDP

IPSec-Over-UDP-Port

Banner2

Security Appliance Supported RADIUS Attributes and Values (continued)

PPTP-MPPC-Compression

VPN

3000 ASA PIX

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Attr.

#

21

25

27

28

29

30

31

33

34

35

36

37

Syntax/

Type

Single or

Multi-


Integer Single Bitmap:


2 = 40 bit

4 = 128 bits

8 = Stateless-Req

15= 40/128-Encr/Stateless-Req

String Single Sets the group policy for the remote access VPN session. For version 8.2 and later, use this attribute instead of

IETF-Radius-Class. You can use one of the three following formats:

•

•

<group policy name>


•


String Single Specifies the name of the network/access list that describes the split tunnel inclusion list

String Single Specifies the single default domain name to send to the client (1-255 characters)

String Single Specifies the list of secondary domain names to send to the client (1-255 characters)

Integer Single 1 = LAN-to-LAN

2 = Remote access

Boolean Single 0 = Disabled

1 = Enabled


1 = Enabled


1 = Enabled

Integer Single 4001 - 49151, default = 10000

String Single A banner string that is concatenated to the Banner1 string, if configured.

Integer Single 0 = Disabled

1 = Enabled

B-32


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Table B-7

Attribute Name

L2TP-MPPC-Compression

IKE-Keep-Alives


IPSec-IP-Compression

IPSec-IKE-Peer-ID-Check

IPSec-Auth-On-Rekey

Required-Client- Firewall-Vendor-Code

Required-Client-Firewall-Product-Code

Required-Client-Firewall-Description

Require-HW-Client-Auth

Required-Individual-User-Auth

Authenticated-User-Idle-Timeout

VPN

3000 ASA PIX

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Attr.

#

Syntax/

Type

Single or

Multi-


38 Integer Single 0 = Disabled

1 = Enabled


1 = Enabled

40 Integer Single 1 = Required

2 = If supported by peer certificate

3 = Do not check


1 = Enabled


1 = Enabled

45 Integer Single 1 = Cisco Systems (with Cisco

Integrated Client)

2 = Zone Labs

3 = NetworkICE

4 = Sygate


Intrusion Prevention Security

Agent)

46 Integer Single Cisco Systems Products:

1 = Cisco Intrusion Prevention

Security Agent or Cisco

Integrated Client (CIC)

Zone Labs Products:

1 = Zone Alarm

2 = Zone AlarmPro

3 = Zone Labs Integrity

NetworkICE Product:

1 = BlackIce Defender/Agent

Sygate Products:

1 = Personal Firewall

2 = Personal Firewall Pro

3 = Security Agent

47 String Single String


1 = Enabled


1 = Enabled

50 Integer Single 1-35791394 minutes

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B-33



Table B-7 Security Appliance Supported RADIUS Attributes and Values (continued)

Attribute Name

Cisco-IP-Phone-Bypass

IPSec-Split-Tunneling-Policy

IPSec-Required-Client-Firewall-Capability

IPSec-Client-Firewall-Filter-Name

IPSec-Client-Firewall-Filter-Optional

IPSec-Backup-Servers

IPSec-Backup-Server-List

DHCP-Network-Scope

Intercept-DHCP-Configure-Msg

MS-Client-Subnet-Mask

Allow-Network-Extension-Mode

Authorization-Type

Authorization-Required

Authorization-DN-Field

IKE-KeepAlive-Confidence-Interval

WebVPN-Content-Filter-Parameters

VPN

3000 ASA PIX

Y Y Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Attr.

#

51

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

Syntax/

Type

Single or

Multi-



1 = Enabled

Integer Single 0 = No split tunneling

1 = Split tunneling

2 = Local LAN permitted

Integer Single 0 = None

1 = Policy defined by remote

FW Are-You-There (AYT)

2 = Policy pushed CPP

4 = Policy from server

String Single Specifies the name of the filter to be pushed to the client as firewall policy

Integer Single 0 = Required

1 = Optional

String Single 1 = Use Client-Configured list

2 = Disable and clear client list

3 = Use Backup Server list

String Single Server Addresses (space delimited)

String Single IP Address


1 = Enabled

Boolean Single An IP address


1 = Enabled

Integer Single 0 = None

1 = RADIUS

2 = LDAP

Integer Single 0 = No

1 = Yes

String Single Possible values: UID, OU, O,

CN, L, SP, C, EA, T, N, GN, SN,

I, GENQ, DNQ, SER, use-entire-name

Integer Single 10-300 seconds

Integer Single 1 = Java ActiveX

2 = Java Script

4 = Image

8 = Cookies in images

B-34


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Table B-7

Attribute Name

WebVPN-URL-List

WebVPN-Port-Forward-List

WebVPN-Access-List

Cisco-LEAP-Bypass

WebVPN-Homepage

Client-Type-Version-Limiting

WebVPN-Port-Forwarding-Name

IE-Proxy-Server


IE-Proxy-Server-Policy

IE-Proxy-Exception-List

IE-Proxy-Bypass-Local

IKE-Keepalive-Retry-Interval

Tunnel-Group-Lock

Access-List-Inbound

Access-List-Outbound

Perfect-Forward-Secrecy-Enable

NAC-Enable

NAC-Status-Query-Timer

NAC-Revalidation-Timer

NAC-Default-ACL

WebVPN-URL-Entry-Enable

Y

Y

Y

Y

Y

Y

Y

Y

Y

VPN

3000 ASA PIX

Y

Y

Y

Y

Y Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Attr.

#

Syntax/

Type

Single or

Multi-


71 String Single URL-List name

72 String Single Port-Forward list name

73 String Single Access-List name


1 = Enabled

76 String Single A URL such as http://example-portal.com

77 String Single IPSec VPN version number string

79 String Single String name (example,

“Corporate-Apps”).

This text replaces the default string, “Application Access,” on the clientless portal home page.

String Single IP address 80

81 Integer Single 1 = No Modify

2 = No Proxy

3 = Auto detect

4 = Use Concentrator Setting

82 String Single newline (\n) separated list of

DNS domains

83 Integer Single 0 = None

1 = Local

84 Integer Single 2 - 10 seconds

85 String Single Name of the tunnel group or

“none”

86 String Single Access list ID

87 String Single Access list ID

88 Boolean Single 0 = No

1 = Yes

89 Integer Single 0 = No

1 = Yes

90

91

Integer Single 30 - 1800 seconds

Integer Single 300 - 86400 seconds

92 String

93 Integer Single

Access list

0 = Disabled

1 = Enabled

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B-35



Table B-7 Security Appliance Supported RADIUS Attributes and Values (continued)

Attribute Name

WebVPN-File-Access-Enable

WebVPN-File-Server-Entry-Enable

WebVPN-File-Server-Browsing-Enable

WebVPN-Port-Forwarding-Enable

WebVPN-Outlook-Exchange-Proxy-Enable

WebVPN-Port-Forwarding-HTTP-Proxy

WebVPN-Auto-Applet-Download-Enable

WebVPN-Citrix-Metaframe-Enable

WebVPN-Apply-ACL

WebVPN-SSL-VPN-Client-Enable

WebVPN-SSL-VPN-Client-Required

WebVPN-SSL-VPN-Client-Keep-

Installation

SVC-Keepalive

SVC-DPD-Interval-Client

SVC-DPD-Interval-Gateway

SVC-Rekey-Time

WebVPN-Deny-Message

Extended-Authentication-On-Rekey

SVC-DTLS

VPN

3000 ASA PIX

Y Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Attr.

#

94

95

96

97

98

Syntax/

Type

Single or

Multi-



1 = Enabled


1 = Enabled


1 = Enabled


1 = Enabled


1 = Enabled


1 = Enabled


1 = Enabled


1 = Enabled


1 = Enabled


1 = Enabled


1 = Enabled


1 = Enabled

107 Integer Single 0 = Off

15 - 600 seconds

108 Integer Single 0 = Off

5 - 3600 seconds

109 Integer Single 0 = Off)

5 - 3600 seconds


1- 10080 minutes

116 String Single Valid string(up to 500 characters)


1 = Enabled

123 Integer Single 0 = False

1 = True

B-36


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Table B-7

Attribute Name

SVC-MTU

SVC-Modules

SVC-Profiles

SVC-Ask

SVC-Ask-Timeout

IE-Proxy-PAC-URL

Strip-Realm

Smart-Tunnel

VLAN

NAC-Settings

Member-Of

Address-Pools

IPv6-Address-Pools

IPv6-VPN-Filter

Privilege-Level


WebVPN-ActiveX-Relay

Smart-Tunnel-Auto

Smart-Tunnel-Auto-Signon-Enable

VPN

3000 ASA PIX

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Y

Attr.

#

Syntax/

Type

Single or

Multi-


125 Integer Single MTU value

256 - 1406 in bytes

127 String Single String (name of a module)

128 String Single String (name of a profile)

131 String Single 0 = Disabled

1 = Enabled

3 = Enable default service

5 = Enable default clientless

(2 and 4 not used)

132 Integer Single 5 - 120 seconds

133 String Single PAC Address String


1 = Enabled

136 String Single Name of a Smart Tunnel


Otherwise = Enabled


1 = Enabled

2 = AutoStart

139 String Single Name of a Smart Tunnel Auto

Signon list appended by the domain name

140 Integer Single 0 - 4094

141 String Single Name of NAC policy

145 String Single Comma delimited string, for example:

Engineering, Sales

This is an administrative attribute that can be used in dynamic access policies. It does not set a group policy.

217 String Single Name of IP local pool

218 String Single Name of IP local pool-IPv6

219 String Single ACL value

220 Integer Single An integer between 0 and 15.

OL-20339-01


B-37



Table B-7

Attribute Name


WebVPN-Macro-Value1

WebVPN-Macro-Value2

VPN

3000 ASA PIX

Y

Y

Attr.

#

Syntax/

Type

Single or

Multi-


223 String Single Unbounded. See the


for examples and use cases at this

URL: http://supportwiki.cisco.com/Vi ewWiki/index.php/Cisco_ASA

_5500_SSL_VPN_Deployment

_Guide%2C_Version_8.x

224 String Single Unbounded. See the


for examples and use cases at this

URL: http://supportwiki.cisco.com/Vi ewWiki/index.php/Cisco_ASA

_5500_SSL_VPN_Deployment

_Guide%2C_Version_8.x

Security Appliance IETF RADIUS Authorization Attributes

Table B-8

Table B-8

list all the possible IETF Radius attributes.

Security Appliance Supported IETF RADIUS Attributes and Values

Attribute Name

IETF-Radius-Class

IETF-Radius-Filter-Id

VPN

3000 ASA PIX

Y Y Y

Y

IETF-Radius-Framed-IP-Address Y

IETF-Radius-Framed-IP-Netmask Y

Y

Y

Y

Y

Y

Y

Attr.

#

25

11 n/a n/a

Syntax/

Type

String

String

String

Single or

Multi-


Single Sets the group policy for the remote access VPN session. For 8.2 and later, we recommend that you use the Group-Policy attribute. You can use one of the three following formats:

•

•

<group policy name>


Single

Single

Single

•


Access list name that is defined on the adaptive security appliance. This applies only to full tunnel IPsec and

SSL VPN clients

An IP address

An IP address mask

B-38


OL-20339-01


Configuring an External TACACS+ Server

Table B-8 Security Appliance Supported IETF RADIUS Attributes and Values

IETF-Radius-Idle-Timeout

IETF-Radius-Service-Type

Y

Y

Y

Y

Y

Y

28

6

Integer

Integer

Single

Single

IETF-Radius-Session-Timeout Y Y Y 27 Integer Single seconds seconds. Possible Service Type values:

.Administrative—user is allowed access to configure prompt.

.NAS-Prompt—user is allowed access to exec prompt.

.remote-access—user is allowed network access seconds

.


The adaptive security appliance provides support for TACACS+ attributes. TACACS+ separates the functions of authentication, authorization, and accounting. The protocol supports two types of attributes: mandatory and optional. Both the server and client must understand a mandatory attribute, and the mandatory attribute must be applied to the user. An optional attribute may or may not be understood or used.

Note

To use TACACS+ attributes, make sure you have enabled AAA services on the NAS.

Table B-9 lists supported TACACS+ authorization response attributes for cut-through-proxy

connections.

Table B-10 lists supported TACACS+ accounting attributes.

Table B-9 Supported TACACS+ Authorization Response Attributes

Attribute

acl idletime timeout

Description

Identifies a locally configured access list to be applied to the connection.

Indicates the amount of inactivity in minutes that is allowed before the authenticated user session is terminated.

Specifies the absolute amount of time in minutes that authentication credentials remain active before the authenticated user session is terminated.

Table B-10

Attribute

bytes_in bytes_out cmd disc-cause

Supported TACACS+ Accounting Attributes

Description

Specifies the number of input bytes transferred during this connection (stop records only).

Specifies the number of output bytes transferred during this connection (stop records only).

Defines the command executed (command accounting only).

Indicates the numeric code that identifies the reason for disconnecting (stop records only).

OL-20339-01


B-39



Table B-10

Attribute

elapsed_time foreign_ip local_ip

NAS port packs_in packs_out priv-level rem_iddr service task_id username

Supported TACACS+ Accounting Attributes (continued)

Description

Defines the elapsed time in seconds for the connection (stop records only).

Specifies the IP address of the client for tunnel connections. Defines the address on the lowest security interface for cut-through-proxy connections.

Specifies the IP address that the client connected to for tunnel connections. Defines the address on the highest security interface for cut-through-proxy connections.

Contains a session ID for the connection.

Specifies the number of input packets transferred during this connection.

Specifies the number of output packets transferred during this connection.

Set to the user’s privilege level for command accounting requests or to 1 otherwise.

Indicates the IP address of the client.

Specifies the service used. Always set to “shell” for command accounting only.

Specifies a unique task ID for the accounting transaction.

Indicates the name of the user.

B-40


OL-20339-01

G L O S S A R Y

Numerics | A

|

B

|

C

|

D

|

E | F |

G | H |

I

| J

|

K | L | M

|

N

| O | P |

Q | R |

S |

T

|

U

|

V

|

W | X

Numerics

3DES

See

DES .

A

AAA

ABR

ACE

Access Modes

Authentication, authorization, and accounting. See also TACACS+ and

RADIUS .

Area Border Router. In

OSPF , a router with interfaces in multiple areas.

access control entry. Information entered into the configuration that lets you specify what type of traffic

to permit or deny on an interface

. By default, traffic that is not explicitly permitted is denied.

The adaptive security appliance CLI uses several command modes. The commands available in each mode vary. See also

user EXEC mode ,

privileged EXEC mode ,

global configuration mode

,

command-specific configuration mode

.

ACL

ActiveX

access control list. A collection of

ACE s. An ACL lets you specify what type of traffic to allow on an

interface. By default, traffic that is not explicitly permitted is denied. ACLs are usually applied to the

interface

which is the source of inbound traffic. See also

rule ,

outbound ACL

.

A set of object-oriented programming technologies and tools used to create mobile or portable programs. An ActiveX program is roughly equivalent to a Java applet.

Address Resolution

Protocol

See

ARP .

address translation

The translation of a network address and/or port to another network address/or port. See also

IP address ,

interface PAT ,

NAT ,

PAT ,

Static PAT

,

xlate .

AES

AH

AIP

Advanced Encryption Standard. A symmetric block cipher that can encrypt and decrypt information.

The AES algorithm is capable of using cryptographic keys of 128, 192 and 256 bits to encrypt and decrypt data in blocks of 128 bits. See also

DES

.

Authentication Header. An IP protocol (type 51) that can ensure data integrity, authentication, and replay detection. AH is embedded in the data to be protected (a full IP datagram, for example). AH can be used either by itself or with

ESP . AH is an older

IPsec protocol that is less important in most

networks than ESP . AH provides authentication services but does not provide encryption services. It is

provided to ensure compatibility with

IPsec

peers that do not support

ESP

, which provides both

authentication

and

encryption . See also encryption

and

VPN . Refer to the RFC 2402.

Advanced Inspection and Prevention. For example, the AIP SSM or AIP SSC, which runs IPS software.


OL-20339-01 GL-1

Glossary

A record address

APCF

ARP

ASA

ASA

ASDM asymmetric encryption authentication

Auto Applet

Download auto-signon

“A” stands for address, and refers to name-to-address mapped records in

DNS

.

Application Profile Customization Framework. Lets the security appliance handle nonstandard applications so that they render correctly over a clientless SSL VPN connection.

Address Resolution Protocol. A low-level TCP/IP protocol that maps a hardware address, or MAC address, to an IP address. An example hardware address is 00:00:a6:00:01:ba. The first three groups of characters (00:00:a6) identify the manufacturer; the rest of the characters (00:01:ba) identify the system card. ARP is defined in RFC 826.

Adaptive Security Algorithm. Used by the adaptive security appliance to perform inspections. ASA allows one-way (inside to outside) connections without an explicit configuration for each internal system and application. See also

inspection engine .

adaptive adaptive security appliance.

Adaptive Security Device Manager. An application for managing and configuring a single adaptive security appliance.

Also called public key systems, asymmetric encryption allows anyone to obtain access to the public key of anyone else. Once the public key is accessed, you can send an encrypted message to that person using the public key. See also

encryption

, public key

.

Cryptographic protocols and services that verify the identity of users and the integrity of data. One of the functions of the

IPsec

framework. Authentication establishes the integrity of the datastream and ensures that it is not tampered with in transit. It also provides confirmation about the origin of the datastream. See also

AAA ,

encryption , and

VPN .

Automatically downloads the clientless SSL VPN port-forwarding applet when the user first logs in to clientless SSL VPN.

This command provides a single sign-on method for clientless SSL VPN users. It passes the clientless

SSL VPN login credentials (username and password) to internal servers for authentication using

NTLM authentication, basic authentication, or both.

B backup server

BGP

BLT stream

BOOTP

BPDU

IPsec backup servers let a VPN client connect to the central site when the primary security appliance is unavailable.

Border Gateway Protocol. BGP performs interdomain routing in TCP/IP networks. BGP is an Exterior

Gateway Protocol, which means that it performs routing between multiple autonomous systems or domains and exchanges routing and access information with other BGP systems. The adaptive security

appliance does not support BGP. See also EGP

.

Bandwidth Limited Traffic stream. Stream or flow of packets whose bandwidth is constrained.

Bootstrap Protocol. Lets diskless workstations boot over the network as is described in RFC 951 and

RFC 1542.

Bridge Protocol Data Unit. Spanning-Tree Protocol hello packet that is sent out at configurable intervals to exchange information among bridges in the network. Protocol data unit is the OSI term for packet.


GL-2 OL-20339-01

Glossary

C

CA cache

CBC certificate

CHAP

CIFS

Citrix

CLI

Certificate Authority, Certification Authority. A third-party entity that is responsible for issuing and revoking certificates. Each device with the public key of the CA can authenticate a device that has a certificate issued by the CA. The term CA also refers to software that provides CA services. See also

certificate ,

CRL

,

public key , RA .

A temporary repository of information accumulated from previous task executions that can be reused, decreasing the time required to perform the tasks. Caching stores frequently reused objects in the system cache, which reduces the need to perform repeated rewriting and compressing of content.

Cipher Block Chaining. A cryptographic technique that increases the encryption strength of an algorithm. CBC requires an initialization vector (IV) to start encryption. The IV is explicitly given in the

IPsec packet.

A signed cryptographic object that contains the identity of a user or device and the public key of the

CA that issued the certificate. Certificates have an expiration date and may also be placed on a

CRL if

known to be compromised. Certificates also establish non-repudiation for IKE negotiation, which

means that you can prove to a third party that

IKE

negotiation was completed with a specific peer.

Challenge Handshake Authentication Protocol.

Common Internet File System. It is a platform-independent file sharing system that provides users with network access to files, printers, and other machine resources. Microsoft implemented CIFS for networks of Windows computers, however, open source implementations of CIFS provide file access to servers running other operating systems, such as Linux, UNIX, and Mac OS X.

An application that virtualizes client-server applications and optimizes web applications.

command-line interface. The primary interface for entering configuration and monitoring commands to the adaptive security appliance.

client/server computing

Client update

Distributed computing (processing) network systems in which transaction responsibilities are divided into two parts: client (front end) and server (back end). Also called distributed computing. See also

RPC

.

Lets you update revisions of clients to which the update applies; provide a URL or IP address from which to get the update; and, in the case of Windows clients, optionally notify users that they should update their VPN client version.

command-specific configuration mode

From global configuration mode, some commands enter a command-specific configuration mode. All user EXEC, privileged EXEC, global configuration, and command-specific configuration commands are available in this mode. See also


, privileged EXEC mode

,

user EXEC mode

.

compression configuration, config, config file

The process of encoding information using fewer bits or other information-bearing units than an unencoded representation would use. Compression can reduce the size of transferring packets and increase communication performance.

A file on the adaptive security appliance that represents the equivalent of settings, preferences, and properties administered by

ASDM or the

CLI .

OL-20339-01


GL-3

Glossary

Content

Rewriting/Transfor mation

Interprets and modifies applications so that they render correctly over a clientless SSL VPN connection.

cookie

CPU

CRC

CRL

CRV cryptography crypto map

CTIQBE cut-through proxy

A cookie is a object stored by a browser. Cookies contain information, such as user preferences, to persistent storage.

Central Processing Unit. Main processor.

Cyclical Redundancy Check. Error-checking technique in which the frame recipient calculates a remainder by dividing frame contents by a prime binary divisor and compares the calculated remainder to a value stored in the frame by the sending node.

Certificate Revocation List. A digitally signed message that lists all of the current but revoked certificates listed by a given

CA

. A CRL is analogous to a book of stolen charge card numbers that allow stores to reject bad credit cards. When certificates are revoked, they are added to a CRL. When you implement authentication using certificates, you can choose to use CRLs or not. Using CRLs lets you easily revoke certificates before they expire, but the CRL is generally only maintained by the

CA

or an

RA . If you are using CRLs and the connection to the

CA or

RA

is not available when authentication is requested, the authentication request will fail. See also

CA , certificate

, public key , RA .

Call Reference Value. Used by

H.225.0

to distinguish call legs signaled between two entities.

Encryption, authentication, integrity, keys and other services used for secure communication over networks. See also

VPN and

IPsec .

A data structure with a unique name and sequence number that is used for configuring VPNs on the adaptive security appliance. A crypto map selects data flows that need security processing and defines the policy for these flows and the crypto peer that traffic needs to go to. A crypto map is applied to an

interface. Crypto maps contain the ACL

s, encryption standards, peers, and other parameters necessary to specify security policies for

VPN

s using

IKE

and

IPsec

. See also

VPN .

Computer Telephony Interface Quick Buffer Encoding. A protocol used in IP telephony between the

Cisco CallManager and CTI

TAPI and

JTAPI

applications. CTIQBE is used by the TAPI/JTAPI protocol inspection module and supports

NAT ,

PAT , and bidirectional

NAT

. This protocol enables

Cisco IP SoftPhone and other Cisco TAPI/JTAPI applications to communicate with Cisco CallManager for call setup and voice traffic across the adaptive security appliance.

Enables the adaptive security appliance to provide faster traffic flow after user authentication. The cut-through proxy challenges a user initially at the application layer. After the security appliance authenticates the user, it shifts the session flow and all traffic flows directly and quickly between the source and destination while maintaining session state information.

D data confidentiality

Describes any method that manipulates data so that no attacker can read it. This is commonly achieved by data encryption and

key s that are only available to the parties involved in the communication.

data integrity

Describes mechanisms that, through the use of encryption based on

secret key or

public key

algorithms, allow the recipient of a piece of protected data to verify that the data has not been modified in transit.

GL-4


OL-20339-01

Glossary data origin authentication decryption

DES

DHCP

DoS

DSL

DSP

DSS

A security service where the receiver can verify that protected data could have originated only from the sender. This service requires a data integrity service plus a

key

distribution mechanism, where a

secret key is shared only between the sender and receiver.

Application of a specific algorithm or cipher to encrypted data so as to render the data comprehensible to those who are authorized to see the information. See also

encryption .

Data encryption standard. DES was published in 1977 by the National Bureau of Standards and is a secret key encryption scheme based on the Lucifer algorithm from IBM. Cisco uses DES in classic crypto (40-bit and 56-bit key lengths),

IPsec

crypto (56-bit key), and 3DES (triple DES), which performs encryption three times using a 56-bit key. 3DES is more secure than DES but requires more processing for encryption and decryption. See also

AES ,

ESP

.

Dynamic Host Configuration Protocol. Provides a mechanism for allocating IP addresses to hosts dynamically, so that addresses can be reused when hosts no longer need them and so that mobile computers, such as laptops, receive an IP address applicable to the

LAN

to which it is connected.

Diffie-Hellman

A public key cryptography protocol that allows two parties to establish a shared secret over insecure communications channels. Diffie-Hellman is used within

IKE to establish session keys.

Diffie-Hellman is a component of

Oakley key exchange.

Diffie-Hellman

Group 1, Group 2,

Group 5, Group 7

Diffie-Hellman refers to a type of public key cryptography using asymmetric encryption based on large prime numbers to establish both Phase 1 and Phase 2

SA

s. Group 1 provides a smaller prime number than Group 2 but may be the only version supported by some

IPsec peers. Diffe-Hellman

Group 5 uses a 1536-bit prime number, is the most secure, and is recommended for use with AES

.

Group 7 has an elliptical curve field size of 163 bits and is for use with the Movian VPN client, but works with any peer that supports Group 7 (ECC). See also

VPN

and encryption .

Note

The

group 7

command option was deprecated in ASA Version 8.0(4). Attempts to configure group 7 will generate an error message and use group 5 instead.

digital certificate

DMZ

DN

DNS

See

certificate

.

See

interface .

Distinguished Name. Global, authoritative name of an entry in the OSI Directory (X.500).

Domain Name System (or Service). An Internet service that translates domain names into IP addresses.

Denial of Service. A type of network attack in which the goal is to render a network service unavailable.

digital subscriber line. Public network technology that delivers high bandwidth over conventional copper wiring at limited distances. DSL is provisioned via modem pairs, with one modem located at a central office and the other at the customer site. Because most DSL technologies do not use the whole bandwidth of the twisted pair, there is room remaining for a voice channel.

digital signal processor. A DSP segments a voice signal into frames and stores them in voice packets.

Digital Signature Standard. A digital signature algorithm designed by The US National Institute of

Standards and Technology and based on public-key cryptography. DSS does not do user datagram

encryption. DSS is a component in classic crypto, as well as the Redcreek IPsec card, but not in IPsec

implemented in Cisco IOS software.

OL-20339-01


GL-5

Glossary

Dynamic NAT

Dynamic PAT

See NAT

and

address translation

.

Dynamic Port Address Translation. Dynamic PAT lets multiple outbound sessions appear to originate from a single IP address. With PAT enabled, the adaptive security appliance chooses a unique port number from the PAT IP address for each outbound translation slot (

xlate

). This feature is valuable when an

ISP

cannot allocate enough unique IP addresses for your outbound connections. The global pool addresses always come first, before a PAT address is used. See also

NAT

, Static PAT

, and

xlate .

E

ECHO

EGP

EIGRP

EMBLEM encryption

ESMTP

ESP

See ping ,

ICMP

. See also

inspection engine

.

Exterior Gateway Protocol. Replaced by BGP. The adaptive security appliance does not support EGP.

See also

BGP

.

Enhanced Interior Gateway Routing Protocol. The adaptive security appliance does not support

EIGRP.

Enterprise Management BaseLine Embedded Manageability. A syslog format designed to be consistent with the Cisco IOS system log format and is more compatible with CiscoWorks management applications.

Application of a specific algorithm or cipher to data so as to render the data incomprehensible to those unauthorized to see the information. See also

decryption

.

Extended

SMTP . Extended version of SMTP that includes additional functionality, such as delivery

notification and session delivery. ESMTP is described in RFC 1869, SMTP Service Extensions.

Encapsulating Security Payload. An IPsec protocol, ESP provides authentication and encryption

services for establishing a secure tunnel over an insecure network. For more information, refer to

RFCs 2406 and 1827.

F failover, failover mode

Fixup

Flash, Flash memory

FQDN/IP

Failover lets you configure two adaptive security appliances so that one will take over operation if the other one fails. The adaptive security appliance supports two failover configurations, Active/Active failover and Active/Standby failover. Each failover configuration has its own method for determining and performing failover. With Active/Active failover, both units can pass network traffic.

Active/Active failover lets you configure load balancing on your network. Active/Active failover is only available on units running in multiple context mode. With Active/Standby failover, only one unit passes traffic while the other unit waits in a standby state. Active/Standby failover is available on units running in either single or multiple context mode.

See inspection engine

.

A nonvolatile storage device used to store the configuration file when the adaptive security appliance is powered down.

Fully qualified domain name/IP address.

IPsec

parameter that identifies peers that are security gateways.


GL-6 OL-20339-01

H

H.225

H.225.0

H.245

H.320

FragGuard

FTP

Glossary

Provides IP fragment protection and performs full reassembly of all

ICMP

error messages and virtual reassembly of the remaining IP fragments that are routed through the adaptive security appliance.

File Transfer Protocol. Part of the TCP/IP protocol stack, used for transferring files between hosts.

G

GGSN

gateway

GPRS support node. A wireless gateway that allows mobile cell phone users to access the

public data network or specified private IP networks.

global configuration mode

Global configuration mode lets you change the adaptive security appliance configuration. All user

EXEC, privileged EXEC, and global configuration commands are available in this mode. See also

user

EXEC mode

,

privileged EXEC mode

, command-specific configuration mode

.

GMT

GPRS

GRE

GSM

GTP

Greenwich Mean Time. Replaced by UTC (Coordinated Universal Time) in 1967 as the world time standard.

general packet radio service. A service defined and standardized by the European Telecommunication

Standards Institute. GPRS is an IP-packet-based extension of

GSM networks and provides mobile,

wireless, data communications

Generic Routing Encapsulation described in RFCs 1701 and 1702. GRE is a tunneling protocol that can encapsulate a wide variety of protocol packet types inside IP tunnels, creating a virtual point-to-point link to routers at remote points over an IP network. By connecting multiprotocol subnetworks in a single-protocol backbone environment, IP tunneling using GRE allows network expansion across a single protocol backbone environment.

Global System for Mobile Communication. A digital, mobile, radio standard developed for mobile, wireless, voice communications.

GPRS tunneling protocol. GTP handles the flow of user packet data and signaling information

between the SGSN and

GGSN

in a

GPRS network. GTP is defined on both the Gn and Gp interfaces

of a

GPRS

network.

A protocol used for TCP signaling in applications such as video conferencing. See also H.323

and

inspection engine

.

An ITU standard that governs H.225.0 session establishment and packetization. H.225.0 actually describes several different protocols: RAS, use of Q.931, and use of

RTP

.

An ITU standard that governs H.245 endpoint control.

Suite of ITU-T standard specifications for video conferencing over circuit-switched media, such as

ISDN, fractional T-1, and switched-56 lines. Extensions of ITU-T standard H.320 enable video conferencing over LANs and other packet-switched networks, as well as video over the

Internet

.

OL-20339-01


GL-7

I

IANA

ICMP

IDS

IETF

IGMP

Glossary

H.323

H.323 RAS

H.450.2

H.450.3

Hash, Hash

Algorithm headend

HMAC host host/network

HTTP

HTTPS

Allows dissimilar communication devices to communicate with each other by using a standardized communication protocol. H.323 defines a common set of CODECs, call setup and negotiating procedures, and basic data transport methods.

Registration, admission, and status signaling protocol. Enables devices to perform registration,

admissions, bandwidth changes, and status and disengage procedures between VoIP gateway and the

gatekeeper.

Call transfer supplementary service for

H.323

.

Call diversion supplementary service for

H.323

.

A hash algorithm is a one-way function that operates on a message of arbitrary length to create a fixed-length message digest used by cryptographic services to ensure its data integrity. MD5 has a smaller digest and is considered to be slightly faster than

SHA-1 . Cisco uses both SHA-1 and

MD5

hashes within our implementation of the

IPsec framework. See also

encryption

,

HMAC , and

VPN .

A firewall, concentrator, or other host that serves as the entry point into a private network for

VPN

client connections over the public network. See also

ISP

and

VPN

.

A mechanism for message authentication using cryptographic hashes such as

SHA-1 and

MD5 .

The name for any device on a TCP/IP network that has an IP address. See also network

and

node .

An IP address and netmask used with other information to identify a single host or network subnet for adaptive security appliance configuration, such as an address translation (

xlate ) or

ACE .

Hypertext Transfer Protocol. A protocol used by browsers and web servers to transfer files. When a user views a web page, the browser can use HTTP to request and receive the files used by the web page. HTTP transmissions are not encrypted.

Hypertext Transfer Protocol Secure. An

SSL

-encrypted version of HTTP.

Internet Assigned Number Authority. Assigns all port and protocol numbers for use on the

Internet

.

Internet Control Message Protocol. Network-layer Internet protocol that reports errors and provides other information relevant to IP packet processing.

Intrusion Detection System. A method of detecting malicious network activity by signatures and then implementing a policy for that signature.

The Internet Engineering Task Force. A technical standards organization that develops

RFC

documents defining protocols for the

Internet .

Internet Group Management Protocol. IGMP is a protocol used by IPv4 systems to report IP

multicast

memberships to neighboring multicast routers.

GL-8


OL-20339-01

Glossary

IKE

IKE Extended

Authentication

IKE Mode

Configuration

ILS

IMAP implicit rule

IMSI inside inspection engine interface

Internet Key Exchange. IKE establishes a shared security policy and authenticates keys for services

(such as

IPsec ) that require keys. Before any IPsec

traffic can be passed, each adaptive security appliance must verify the identity of its peer. Identification can be done by manually entering preshared keys into both hosts or by a

CA

service. IKE is a hybrid protocol that uses part

Oakley

and part of another protocol suite called

SKEME

inside the

ISAKMP

framework. IKE (formerly known as

ISAKMP/Oakley) is defined in RFC 2409.

IKE Extended Authenticate (Xauth) is implemented per the IETF draft-ietf-ipsec-isakmp-xauth-04.txt

(extended authentication). This protocol provides the capability of authenticating a user within IKE using

TACACS+ or

RADIUS

.

IKE Mode Configuration is implemented per the IETF draft-ietf-ipsec-isakmp-mode-cfg-04.txt. IKE

Mode Configuration provides a method for a security gateway to download an IP address (and other network level configuration) to the VPN client as part of an IKE negotiation.

Internet Locator Service. ILS is based on LDAP and is ILSv2 compliant. ILS was developed by

Microsoft for use with its NetMeeting, SiteServer, and Active Directory products.

Internet Message Access Protocol. Method of accessing e-mail or bulletin board messages kept on a mail server that can be shared. IMAP permits client e-mail applications to access remote message stores as if they were local without actually transferring the message.

An access rule automatically created by the adaptive security appliance based on default rules or as a result of user-defined rules.

International Mobile Subscriber Identity. One of two components of a

GTP

tunnel ID, the other being the

NSAPI . See also NSAPI

.

The first interface, usually port 1, that connects your internal, trusted network protected by the adaptive security appliance. See also

interface , interface name .

The adaptive security appliance inspects certain application-level protocols to identify the location of

embedded addressing information in traffic. Inspection allows NAT

to translate these embedded addresses and to update any checksum or other fields that are affected by the translation. Because many protocols open secondary

TCP

or

UDP

ports, each application inspection engine also monitors sessions to determine the port numbers for secondary channels. The initial session on a well-known port is used to negotiate dynamically assigned port numbers. The application inspection engine monitors these sessions, identifies the dynamic port assignments, and permits data exchange on these ports for the duration of the specific session. Some of the protocols that the adaptive security appliance can inspect are

CTIQBE

,

FTP

,

H.323

, HTTP ,

MGCP ,

SMTP , and

SNMP .

The physical connection between a particular network and a adaptive security appliance.

interface IP address

The IP address of the adaptive security appliance network interface. Each interface IP address must be unique. Two or more interfaces must not be given the same IP address or IP addresses that are on the same IP network.

interface name interface PAT

Human-readable name assigned to the adaptive security appliance network interface. The inside interface default name is “inside” and the outside interface default name is “outside.” See also

inside

and

outside

.

The use of

PAT

where the

PAT

IP address is also the IP address of the outside interface. See

Dynamic

PAT

,

Static PAT .

OL-20339-01


GL-9

Glossary

Internet intranet

IP

IPS

IP address

IP pool

IPsec

IPsec Phase 1

The global network that uses IP

. Not a

LAN . See also

intranet .

Intranetwork. A LAN that uses

IP

. See also

network

and

Internet .

Internet Protocol. IP protocols are the most popular nonproprietary protocols because they can be used to communicate across any set of interconnected networks and are equally well suited for

LAN

and

WAN

communications.

Intrusion Prevention Service. An in-line, deep-packet inspection-based solution that helps mitigate a wide range of network attacks.

An IP protocol address. A adaptive security appliance interface ip_address. IP version 4 addresses are

32 bits in length. This address space is used to designate the network number, optional subnetwork number, and a host number. The 32 bits are grouped into four octets (8 binary bits), represented by 4 decimal numbers separated by periods, or dots. The meaning of each of the four octets is determined by their use in a particular network.

A range of local IP addresses specified by a name, and a range with a starting IP address and an ending

address. IP pools are used by DHCP

and

VPN

s to assign local IP addresses to clients on the inside interface.

IP Security. A framework of open standards that provides data confidentiality, data integrity, and data authentication between participating peers. IPsec provides these security services at the IP layer. IPsec uses

IKE

to handle the negotiation of protocols and algorithms based on local policy and to generate the encryption and authentication keys to be used by IPsec. IPsec can protect one or more data flows between a pair of hosts, between a pair of security gateways, or between a security gateway and a host.

The first phase of negotiating

IPsec

, includes the key exchange and the

ISAKMP

portions of

IPsec

.

IPsec Phase 2

The second phase of negotiating

IPsec

. Phase 2 determines the type of encryption rules used for payload, the source and destination that will be used for encryption, the definition of interesting traffic according to access lists, and the

IPsec

peer.

IPsec is applied to the interface in Phase 2.

IPsec transform set

A transform set specifies the

IPsec protocol, encryption algorithm, and hash algorithm to use on traffic matching the IPsec policy. A transform describes a security protocol (

AH

or

ESP ) with its

corresponding algorithms. The

IPsec

protocol used in almost all transform sets is

ESP

with the DES

algorithm and HMAC-SHA for authentication.

ISAKMP

ISP

Internet Security Association and Key Management Protocol. A protocol framework that defines payload formats, the mechanics of implementing a key exchange protocol, and the negotiation of a

security association. See IKE .

Internet Service Provider. An organization that provides connection to the

Internet

via their services, such as modem dial in over telephone voice lines or

DSL .

J

JTAPI

Java Telephony Application Programming Interface. A Java-based API supporting telephony

functions. See also TAPI .

GL-10


OL-20339-01

Glossary

K key

A data object used for encryption

,

decryption , or

authentication

.

L

L2TP

LAN layer, layers

LCN

LDAP

Layer Two Tunneling Protocol. An IETF standards track protocol defined in RFC 2661 that provides tunneling of PPP. L2TP is an extension to the PPP. L2TP merges the older Cisco Layer Two

Forwarding (L2F) protocol with PPTP. L2TP can be used with IPsec encryption and is considered more secure against attack than PPTP.

Local area network. A network residing in one location, such as a single building or campus. See also

Internet , intranet

, and

network

.

Networking models implement layers with which different protocols are associated. The most common networking model is the OSI model, which consists of the following seven layers, in order: physical, data link, network, transport, session, presentation, and application.

Logical channel number.

Lightweight Directory Access Protocol. LDAP provides management and browser applications with access to X.500 directories.

M mask

MCR

MC router

MD5

MDI

MDIX message digest

A 32-bit mask that shows how an

Internet address is divided into network, subnet, and host parts. The

mask has ones in the bit positions to be used for the network and subnet parts, and zeros for the host part. The mask should contain at least the standard network portion, and the subnet field should be contiguous with the network portion.

See

multicast

.

Multicast (MC) routers route multicast data transmissions to the hosts on each LAN in an internetwork

that are registered to receive specific multimedia or other broadcasts. See also multicast .

Message Digest 5. A one-way hashing algorithm that produces a 128-bit hash. Both MD5 and

SHA-1

are variations on MD4 and are designed to strengthen the security of the MD4 hashing algorithm.

SHA-1 is more secure than MD4 and MD5. Cisco uses hashes for authentication within the

IPsec

framework. Also used for message authentication in SNMP v.2. MD5 verifies the integrity of the communication, authenticates the origin, and checks for timeliness.

MD5

has a smaller digest and is considered to be slightly faster than

SHA-1

.

media dependent interface.

media dependent interface crossover.

A message digest is created by a hash algorithm, such as MD5 or

SHA-1 , that is used for ensuring

message integrity.

OL-20339-01


GL-11

Glossary

MGCP

Mode

Mode Config

Modular Policy

Framework

MS

MS-CHAP

MTU multicast

Media Gateway Control Protocol. Media Gateway Control Protocol is a protocol for the control of

VoIP calls by external call-control elements known as media gateway controllers or call agents. MGCP merges the IPDC and

SGCP protocols.

See Access Modes

.

See IKE Mode Configuration

.

A means of configuring adaptive security appliance features in a manner similar to Cisco IOS software

Modular

QoS

CLI.

mobile station. Refers generically to any mobile device, such as a mobile handset or computer, that is used to access network services.

GPRS networks support three classes of MS, which describe the type

of operation supported within the

GPRS and the GSM

mobile wireless networks. For example, a Class

A MS supports simultaneous operation of

GPRS and GSM services.

Microsoft

CHAP

.

maximum transmission unit. The maximum number of bytes in a packet that can flow efficiently across the network with best response time. For Ethernet, the default MTU is 1500 bytes, but each network can have different values, with serial connections having the smallest values. The MTU is described in RFC 1191.

Refers to a network addressing method in which the source transmits a packet to multiple destinations, a multicast group, simultaneously. See also

PIM

, SMR .

N

N2H2

NAT

NEM

NetBIOS netmask network

A third-party, policy-oriented filtering application that works with the adaptive security appliance to control user web access. N2H2 can filter

HTTP

requests based on the destination hostname, destination IP address, username, and password. The N2H2 corporation was acquired by Secure

Computing in October, 2003.

Network Address Translation. Mechanism for reducing the need for globally unique IP addresses.

NAT allows an organization with addresses that are not globally unique to connect to the

Internet by

translating those addresses into a globally routable address space.

Network Extension Mode. Lets

VPN

hardware clients present a single, routable network to the remote private network over the

VPN

tunnel.

Network Basic Input/Output System. A Microsoft protocol that supports Windows hostname registration, session management, and data transfer. The adaptive security appliance supports

NetBIOS by performing

NAT of the packets for NBNS UDP port 137 and NBDS UDP port 138.

See mask .

In the context of adaptive security appliance configuration, a network is a group of computing devices that share part of an IP address space and not a single host. A network consists of multiple nodes or hosts. See also

host ,

Internet , intranet , IP ,

LAN , and

node

.

GL-12


OL-20339-01

Glossary

NMS node

network management system. System responsible for managing at least part of a network. An NMS is generally a reasonably powerful and well-equipped computer, such as an engineering workstation.

NMSs communicate with agents to help keep track of network statistics and resources.

Devices such as routers and printers that would not normally be called hosts. See also

host ,

network .

nonvolatile storage, memory

Storage or memory that, unlike RAM, retains its contents without power. Data in a nonvolatile storage device survives a power-off, power-on cycle.

NSAPI

NSSA

NTLM

NTP

network service access point identifier. One of two components of a

GTP tunnel ID, the other

component being the

IMSI . See also IMSI .

not-so-stubby-area. An OSPF feature described by RFC 1587. NSSA was first introduced in Cisco

IOS software release 11.2. It is a nonproprietary extension of the existing stub area feature that allows the injection of external routes in a limited fashion into the stub area.

NT Lan Manager. A Microsoft Windows challenge-response authentication method.

Network Time Protocol.

O

Oakley object grouping

OSPF

OU outbound outbound ACL outside

A key exchange protocol that defines how to acquire authenticated keying material. The basic mechanism for Oakley is the

Diffie-Hellman

key exchange algorithm. Oakley is defined in RFC 2412.

Simplifies access control by letting you apply access control statements to groups of network objects, such as protocol, services, hosts, and networks.

Open Shortest Path First. OSPF is a routing protocol for IP networks. OSPF is a routing protocol widely deployed in large networks because of its efficient use of network bandwidth and its rapid convergence after changes in topology. The adaptive security appliance supports OSPF.

Organizational Unit. An X.500 directory attribute.

Refers to traffic whose destination is on an interface with lower security than the source interface.

An ACL

applied to outbound traffic.

The first interface, usually port 0, that connects to other untrusted networks outside the adaptive security appliance; the

Internet

. See also

interface , interface name ,

outbound

.

P

PAC

PAT

PDP

OL-20339-01

PPTP

Access Concentrator. A device attached to one or more PSTN or ISDN lines capable of

PPP

operation and of handling the

PPTP

protocol. The PAC needs to implement TCP/IP to pass traffic to one or more

PNS

s. It may also tunnel non-IP protocols.

See

Dynamic PAT ,

interface PAT

, and

Static PAT

.

Packet Data Protocol.


GL-13

Glossary

Phase 1

Phase 2

PIM

PIM-SM ping

PIX

Perfmon

PFS

PKCS12

PNS

Policy NAT

POP

Pool

Port

PPP

The adaptive security appliance feature that gathers and reports a wide variety of feature statistics, such as connections/second, xlates/second, and so on.

Perfect Forwarding Secrecy. PFS enhances security by using a different security key for the

IPsec

Phase 1 and Phase 2 SA s. Without PFS, the same security key is used to establish SA

s in both phases.

PFS ensures that a given

IPsec

SA

key was not derived from any other secret (like some other keys).

In other words, if someone were to break a key, PFS ensures that the attacker would not be able to

derive any other key. If PFS were not enabled, someone could hypothetically break the IKE

SA secret

key, copy all the

IPsec protected data, and then use knowledge of the

IKE

SA secret to compromise

the

IPsec

SA

setup by this IKE

SA

. With PFS, breaking

IKE

would not give an attacker immediate

access to IPsec . The attacker would have to break each IPsec

SA

individually.

See IPsec Phase 1 .

See IPsec Phase 2 .

Protocol Independent Multicast. PIM provides a scalable method for determining the best paths for distributing a specific multicast transmission to a group of hosts. Each host has registered using IGMP to receive the transmission. See also

PIM-SM .

Protocol Independent Multicast-Sparse Mode. With PIM-SM, which is the default for Cisco routers, when the source of a multicast transmission begins broadcasting, the traffic is forwarded from one MC router to the next, until the packets reach every registered host. See also

PIM .

An

ICMP

request sent by a host to determine if a second host is accessible.

Private Internet eXchange. The Cisco PIX 500 series adaptive security appliances ranged from compact, plug-and-play desktop models for small/home offices to carrier-class gigabit models for the most demanding enterprise and service provider environments. Cisco PIX adaptive security appliances provided robust, enterprise-class integrated network security services to create a strong multilayered defense for fast changing network environments. The PIX has been replaced by the Cisco

ASA 5500 series.

A standard for the transfer of PKI-related data, such as private keys, certificates, and other data.

Devices supporting this standard let administrators maintain a single set of personal identity information.

PPTP Network Server. A PNS is envisioned to operate on general-purpose computing/server

platforms. The PNS handles the server side of

PPTP

. Because

PPTP

relies completely on TCP/IP and is independent of the interface hardware, the PNS may use any combination of IP interface hardware including

LAN and

WAN devices.

Lets you identify local traffic for address translation by specifying the source and destination addresses (or ports) in an access list.

Post Office Protocol. Protocol that client e-mail applications use to retrieve mail from a mail server.

See IP pool

.

A field in the packet headers of

TCP

and UDP protocols that identifies the higher level service which

is the source or destination of the packet.

Point-to-Point Protocol. Developed for dial-up

ISP access using analog phone lines and modems.

GL-14


OL-20339-01

Glossary

PPPoE

PPTP

PPTP GRE

PPTP GRE tunnel

PPTP session

PPTP TCP preshared key primary, primary unit privileged EXEC mode

Point-to-Point Protocol over Ethernet. An IP protocol that encapsulates

PPP

packets and sends them over a local network or the internet to establish a connection to a host, usually between a client and an

ISP

.

Point-to-Point Tunneling Protocol. PPTP was introduced by Microsoft to provide secure remote access to Windows networks; however, because it is vulnerable to attack, PPTP is commonly used only when stronger security methods are not available or are not required. PPTP Ports are pptp,

1723/tcp, 1723/udp, and pptp. For more information about PPTP, see RFC 2637. See also

PAC

, PPTP

GRE , PPTP GRE tunnel

,

PNS

,

PPTP session , and PPTP TCP .

Version 1 of GRE for encapsulating PPP traffic.

A tunnel defined by a

PNS

PAC

pair. The tunnel protocol is defined by a modified version of

GRE .

The tunnel carries

PPP

datagrams between the

PAC

and the PNS

. Many sessions are multiplexed on a single tunnel. A control connection operating over

TCP controls the establishment, release, and

maintenance of sessions and of the tunnel itself.

PPTP

is connection-oriented. The

PNS and

PAC

maintain the state for each user that is attached to a

PAC

. A session is created when an end-to-end

PPP connection is attempted between a dial-up user and

the

PNS . The datagrams related to a session are sent over the tunnel between the

PAC

and PNS

.

Standard

TCP

session over which

PPTP

call control and management information is passed. The control session is logically associated with, but separate from, the sessions being tunneled through a

PPTP

tunnel.

A preshared key provides a method of IKE authentication that is suitable for networks with a limited,

static number of

IPsec peers. This method is limited in scalability because the key must be configured

for each pair of

IPsec

peers. When a new

IPsec

peer is added to the network, the preshared key must

be configured for every IPsec peer with which it communicates. Using

certificate

s and

CA

s provides a more scalable method of

IKE authentication.

The adaptive security appliance normally operating when two units, a primary and secondary, are operating in failover mode.

The highest privilege level at the ASA CLI. Any user EXEC mode command will work in privileged

EXEC mode. The privileged EXEC mode prompt appears as follows after you enter the

enable

command: hostname>

enable

hostname#

See also command-specific configuration mode

,


,

user EXEC mode

.

protocol, protocol literals

A standard that defines the exchange of packets between network nodes for communication. Protocols work together in layers. Protocols are specified in the adaptive security appliance configuration as part of defining a security policy by their literal values or port numbers. Possible adaptive security appliance protocol literal values are ahp, eigrp, esp, gre, icmp, igmp, igrp, ip, ipinip, ipsec, nos, ospf, pcp, snp, tcp, and udp.

OL-20339-01


GL-15

Glossary

Proxy-ARP public key

Enables the adaptive security appliance to reply to an

ARP

request for IP addresses in the global pool.

See also

ARP

.

A public key is one of a pair of keys that are generated by devices involved in public key infrastructure.

Data encrypted with a public key can only be decrypted using the associated private key. When a private key is used to produce a digital signature, the receiver can use the public key of the sender to verify that the message was signed by the sender. These characteristics of key pairs provide a scalable and secure method of authentication over an insecure media, such as the

Internet .

Q

QoS

quality of service. Measure of performance for a transmission system that reflects its transmission quality and service availability.

R

RA

RADIUS refresh registration authority replay-detection

RFC

RIP

RLLA route, routing routed firewall mode

Registration Authority. An authorized proxy for a

CA . RAs can perform certificate enrollment and can

issue CRL

s. See also

CA , certificate ,

public key .

Remote Authentication Dial-In User Service. RADIUS is a distributed client/server system that secures networks against unauthorized access. RFC 2058 and RFC 2059 define the RADIUS protocol standard. See also

AAA

and

TACACS+ .

Retrieve the running configuration from the adaptive security appliance and update the screen. The icon and the button perform the same function.

See RA .

A security service where the receiver can reject old or duplicate packets to defeat replay attacks.

Replay attacks rely on the attacker sending out older or duplicate packets to the receiver and the receiver thinking that the bogus traffic is legitimate. Replay-detection is done by using sequence numbers combined with authentication and is a standard feature of

IPsec .

Request for Comments. RFC documents define protocols and standards for communications over the

Internet

. RFCs are developed and published by IETF .

Routing Information Protocol. Interior Gateway Protocol (IGP) supplied with UNIX BSD systems.

The most common IGP in the Internet

. RIP uses hop count as a routing metric.

Reserved Link Local Address. Multicast addresses range from 224.0.0.0 to 239.255.255.255; however only the range 224.0.1.0 to 239.255.255.255 is available to users. The first part of the multicast address range, 224.0.0.0 to 224.0.0.255, is reserved and referred to as the RLLA. These addresses are unavailable.

The path through a

network

.

In routed firewall mode, the adaptive security appliance is counted as a router hop in the network. It

performs NAT between connected networks and can use

OSPF

or RIP . See also

transparent firewall mode .

GL-16


OL-20339-01

RPC

RSA

RSH

RTCP

RTP

RTSP rule running configuration

Glossary

Remote Procedure Call. RPCs are procedure calls that are built or specified by clients and executed on servers, with the results returned over the network to the clients.

A

public key cryptographic algorithm (named after its inventors, Rivest, Shamir, and Adelman) with

a variable key length. The main weakness of RSA is that it is significantly slow to compute compared to popular secret-key algorithms, such as

DES

. The Cisco implementation of IKE uses a

Diffie-Hellman

exchange to get the secret keys. This exchange can be authenticated with RSA (or preshared keys). With the

Diffie-Hellman exchange, the DES

key never crosses the network (not even in encrypted form), which is not the case with the RSA encrypt and sign technique. RSA is not public domain, and must be licensed from RSA Data Security.

Remote Shell. A protocol that allows a user to execute commands on a remote system without having to log in to the system. For example, RSH can be used to remotely examine the status of a number of access servers without connecting to each communication server, executing the command, and then disconnecting from the communication server.

RTP Control Protocol. Protocol that monitors the

QoS of an IPv6

RTP connection and conveys

information about the ongoing session. See also

RTP

.

Real-Time Transport Protocol. Commonly used with IP networks. RTP is designed to provide end-to-end network transport functions for applications transmitting real-time data, such as audio, video, or simulation data, over multicast or unicast network services. RTP provides such services as payload type identification, sequence numbering, timestamping, and delivery monitoring to real-time applications.

Real Time Streaming Protocol. Enables the controlled delivery of real-time data, such as audio and

video. RTSP is designed to work with established protocols, such as RTP

and

HTTP .

Conditional statements added to the adaptive security appliance configuration to define security policy for a particular situation. See also

ACE , ACL ,

NAT .

The configuration currently running in RAM on the adaptive security appliance. The configuration that determines the operational characteristics of the adaptive security appliance.

S

SA

SCCP

security association. An instance of security policy and keying material applied to a data flow. SAs are established in pairs by

IPsec peers during both phases of IPsec . SAs specify the encryption

algorithms and other security parameters used to create a secure tunnel. Phase 1 SAs (

IKE SAs)

establish a secure tunnel for negotiating Phase 2 SAs. Phase 2 SAs (

IPsec

SAs) establish the secure tunnel used for sending user data. Both

IKE and

IPsec use SAs, although SAs are independent of one

another.

IPsec SAs are unidirectional and they are unique in each security protocol. A set of SAs are

needed for a protected data pipe, one per direction per protocol. For example, if you have a pipe that supports

ESP between peers, one ESP

SA is required for each direction. SAs are uniquely identified

by destination ( IPsec

endpoint) address, security protocol ( AH or

ESP

), and Security Parameter Index.

IKE negotiates and establishes SAs on behalf of

IPsec

. A user can also establish

IPsec

SAs manually.

An IKE SA is used by IKE only, and unlike the

IPsec

SA, it is bidirectional.

Skinny Client Control Protocol. A Cisco-proprietary protocol used between Cisco Call Manager and

Cisco

VoIP

phones.

OL-20339-01


GL-17

Glossary

SCEP

SDP secondary unit secret key security context security services

Simple Certificate Enrollment Protocol. A method of requesting and receiving (also known as enrolling) certificates from

CA s.

Session Definition Protocol. An IETF protocol for the definition of Multimedia Services. SDP

messages can be part of

SGCP and

MGCP messages.

The backup adaptive security appliance when two are operating in failover mode.

A secret key is a key shared only between the sender and receiver. See

key

,

public key .

You can partition a single adaptive security appliance into multiple virtual firewalls, known as security contexts. Each context is an independent firewall, with its own security policy, interfaces, and administrators. Multiple contexts are similar to having multiple stand-alone firewalls.

See cryptography

.

serial transmission

A method of data transmission in which the bits of a data character are transmitted sequentially over a single channel.

SGCP

SGSN

SHA-1

Simple Gateway Control Protocol. Controls

VoIP gateways by an external call control element (called

a call-agent).

Serving GPRS Support Node. The SGSN ensures mobility management, session management, and packet relaying functions.

Secure Hash Algorithm 1. SHA-1 [NIS94c] is a revision to SHA that was published in 1994. SHA is closely modeled after MD4 and produces a 160-bit digest. Because SHA produces a 160-bit digest, it is more resistant to brute-force attacks than 128-bit hashes (such as

MD5 ), but it is slower. Secure

Hash Algorithm 1 is a joint creation of the National Institute of Standards and Technology and the

National Security Agency. This algorithm, like other hash algorithms, is used to generate a hash value, also known as a message digest, that acts like a

CRC

used in lower-layer protocols to ensure that message contents are not changed during transmission. SHA-1 is generally considered more secure than

MD5

.

SIP site-to-site VPN

SKEME

SMR

SMTP

Session Initiation Protocol. Enables call handling sessions, particularly two-party audio conferences, or calls. SIP works with

SDP

for call signaling.

SDP specifies the ports for the media stream. Using

SIP, the adaptive security appliance can support any SIP

VoIP gateways and VoIP proxy servers.

A site-to-site

VPN

is established between two IPsec peers that connect remote networks into a single

VPN

. In this type of

VPN , neither

IPsec

peer is the destination nor source of user traffic. Instead, each

IPsec

peer provides encryption and authentication services for hosts on the LAN s connected to each

IPsec

peer. The hosts on each

LAN

send and receive data through the secure tunnel established by the pair of

IPsec peers.

A key exchange protocol that defines how to derive authenticated keying material, with rapid key refreshment.

Stub Multicast Routing. SMR allows the adaptive security appliance to function as a stub router. A stub router is a device that acts as an

IGMP proxy agent. IGMP is used to dynamically register specific

hosts in a multicast group on a particular

LAN

with a multicast router. Multicast routers route multicast data transmissions to hosts that are registered to receive specific multimedia or other broadcasts. A stub router forwards

IGMP messages between hosts and

MC router

s.

Simple Mail Transfer Protocol. SMTP is an Internet protocol that supports email services.

GL-18


OL-20339-01

Glossary

SNMP split tunneling spoofing

SQL*Net

SSC

SSH

SSL

Simple Network Management Protocol. A standard method for managing network devices using data structures called Management Information Bases.

Allows a remote

VPN client simultaneous encrypted access to a private network and clear unencrypted

access to the

Internet . If you do not enable split tunneling, all traffic between the

VPN

client and the adaptive security appliance is sent through an

IPsec

tunnel. All traffic originating from the

VPN client

is sent to the outside interface through a tunnel, and client access to the

Internet

from its remote site is denied.

A type of attack designed to foil network security mechanisms such as filters and access lists. A spoofing attack sends a packet that claims to be from an address from which it was not actually sent.

Structured Query Language Protocol. An Oracle protocol used to communicate between client and server processes.

Security Services Card for the ASA 5505. For example, the AIP SSC.

Secure Shell. An application running on top of a reliable transport layer, such as TCP/IP, that provides strong authentication and encryption capabilities.

Secure Sockets Layer. A protocol that resides between the application layer and TCP/IP to provide transparent encryption of data traffic.

SSM standby unit

Security Services Module. For example, the AIP SSM or CSC SSM.

See

secondary unit

.

stateful inspection

Network protocols maintain certain data, called state information, at each end of a network connection between two hosts. State information is necessary to implement the features of a protocol, such as guaranteed packet delivery, data sequencing, flow control, and transaction or session IDs. Some of the protocol state information is sent in each packet while each protocol is being used. For example, a browser connected to a web server uses

HTTP and supporting TCP/IP protocols. Each protocol layer

maintains state information in the packets it sends and receives. The adaptive security appliance and some other firewalls inspect the state information in each packet to verify that it is current and valid for every protocol it contains. This feature is called stateful inspection and is designed to create a powerful barrier to certain types of computer security threats.

Static PAT subnetmask

Static Port Address Translation. Static PAT is a static address that also maps a local port to a global port. See also

Dynamic PAT ,

NAT .

See

mask

.

T

TACACS+

TAPI

TCP

OL-20339-01

Terminal Access Controller Access Control System Plus. A client-server protocol that supports

AAA

services, including command authorization. See also

AAA ,

RADIUS .

Telephony Application Programming Interface. A programming interface in Microsoft Windows that supports telephony functions.

Transmission Control Protocol. Connection-oriented transport layer protocol that provides reliable full-duplex data transmission.


GL-19

Glossary

TCP Intercept

TDP

Telnet

TFTP

TID

TLS traffic policing transform set

With the TCP intercept feature, once the optional embryonic connection limit is reached, and until the embryonic connection count falls below this threshold, every SYN bound for the affected server is intercepted. For each SYN, the adaptive security appliance responds on behalf of the server with an empty SYN/ACK segment. The adaptive security appliance retains pertinent state information, drops the packet, and waits for the client acknowledgment. If the ACK is received, a copy of the client SYN segment is sent to the server and the

TCP

three-way handshake is performed between the adaptive security appliance and the server. If this three-way handshake completes, the connection may resume as normal. If the client does not respond during any part of the connection phase, then the adaptive security appliance retransmits the necessary segment using exponential back-offs.

Tag Distribution Protocol. TDP is used by tag switching devices to distribute, request, and release tag binding information for multiple network layer protocols in a tag switching network. TDP does not replace routing protocols. Instead, it uses information learned from routing protocols to create tag bindings. TDP is also used to open, monitor, and close TDP sessions and to indicate errors that occur during those sessions. TDP operates over a connection-oriented transport layer protocol with guaranteed sequential delivery (such as

TCP ). The use of TDP does not preclude the use of other

mechanisms to distribute tag binding information, such as piggybacking information on other protocols.

A terminal emulation protocol for TCP/IP networks such as the

Internet

. Telnet is a common way to

control web servers remotely; however, its security vulnerabilities have led to its replacement by SSH

.

Trivial File Transfer Protocol. TFTP is a simple protocol used to transfer files. It runs on UDP and is explained in depth in RFC 1350.

Tunnel Identifier.

Transport Layer Security. A future IETF protocol to replace

SSL

.

The traffic policing feature ensures that no traffic exceeds the maximum rate (bits per second) that you configure, which ensures that no one traffic flow can take over the entire resource.

See IPsec transform set

.

See xlate

.

translate, translation transparent firewall mode

A mode in which the adaptive security appliance is not a router hop. You can use transparent firewall mode to simplify your network configuration or to make the adaptive security appliance invisible to attackers. You can also use transparent firewall mode to allow traffic through that would otherwise be blocked in

routed firewall mode . See also routed firewall mode .

transport mode

TSP tunnel mode

An IPsec encryption mode that encrypts only the data portion (payload) of each packet but leaves the

header untouched. Transport mode is less secure than tunnel mode.

TAPI Service Provider. See also

TAPI

.

An

IPsec

encryption mode that encrypts both the header and data portion (payload) of each packet.

Tunnel mode is more secure than transport mode.

GL-20


OL-20339-01

tunnel

Turbo ACL

Glossary

A method of transporting data in one protocol by encapsulating it in another protocol. Tunneling is used for reasons of incompatibility, implementation simplification, or security. For example, a tunnel lets a remote

VPN

client have encrypted access to a private network.

Increases

ACL lookup speeds by compiling them into a set of lookup tables. Packet headers are used to access the tables in a small, fixed number of lookups, independent of the existing number of ACL

entries.

U

UDP

UMTS

Unicast RPF

URL user EXEC mode

UTC

UTRAN

UUIE

User Datagram Protocol. A connectionless transport layer protocol in the IP protocol stack. UDP is a simple protocol that exchanges datagrams without acknowledgments or guaranteed delivery, which requires other protocols to handle error processing and retransmission. UDP is defined in RFC 768.

Universal Mobile Telecommunication System. An extension of GPRS

networks that moves toward an all-IP network by delivering broadband information, including commerce and entertainment services, to mobile users via fixed, wireless, and satellite networks.

Unicast Reverse Path Forwarding. Unicast RPF guards against spoofing by ensuring that packets have a source IP address that matches the correct source interface according to the routing table.

Uniform Resource Locator. A standardized addressing scheme for accessing hypertext documents and other services using a browser. For example, http://www.cisco.com.

The lowest privilege level at the ASA CLI. The user EXEC mode prompt appears as follows when you first access the adaptive security appliance: hostname>

See also command-specific configuration mode

,


, and

privileged EXEC mode

.

Coordinated Universal Time. The time zone at zero degrees longitude, previously called Greenwich

Mean Time (GMT) and Zulu time. UTC replaced GMT in 1967 as the world time standard. UTC is based on an atomic time scale rather than an astronomical time scale.

Universal Terrestrial Radio Access Network. Networking protocol used for implementing wireless networks in UMTS. GTP allows multi-protocol packets to be tunneled through a UMTS/GPRS backbone between a

GGSN

, an SGSN and the

UTRAN .

User-User Information Element. An element of an

H.225

packet that identifies the users implicated in the message.

V

VLAN

Virtual

LAN

. A group of devices on one or more

LAN s that are configured (using management

software) so that they can communicate as if they were attached to the same physical network cable, when they are located on a number of different

LAN

segments. Because VLANs are based on logical instead of physical connections, they are extremely flexible.

OL-20339-01


GL-21

W

WAN

WCCP

Websense

WEP

WINS

Glossary

VoIP

VPN virtual firewall

VSA

Voice over IP. VoIP carries normal voice traffic, such as telephone calls and faxes, over an IP-based network. DSP segments the voice signal into frames, which are coupled in groups of two and stored in voice packets. These voice packets are transported using IP in compliance with ITU-T specification

H.323

.

Virtual Private Network. A network connection between two peers over the public network that is made private by strict authentication of users and the encryption of all data traffic. You can establish

VPNs between clients, such as PCs, or a

headend , such as the adaptive security appliance.

See security context .

Vendor-specific attribute. An attribute in a

RADIUS packet that is defined by a vendor rather than by

RADIUS RFCs. The RADIUS protocol uses IANA-assigned vendor numbers to help identify VSAs.

This lets different vendors have VSAs of the same number. The combination of a vendor number and a VSA number makes a VSA unique. For example, the cisco-av-pair VSA is attribute 1 in the set of

VSAs related to vendor number 9. Each vendor can define up to 256 VSAs. A

RADIUS packet

contains any VSAs attribute 26, named Vendor-specific. VSAs are sometimes referred to as subattributes.

wide-area network. Data communications network that serves users across a broad geographic area and often uses transmission devices provided by common carriers.

Web Cache Communication Protocol. Transparently redirects selected types of traffic to a group of web cache engines to optimize resource usage and lower response times.

A content filtering solution that manages employee access to the Internet

. Websense uses a policy engine and a

URL database to control user access to websites.

Wired Equivalent Privacy. A security protocol for wireless

LAN

s, defined in the IEEE 802.11b standard.

Windows Internet Naming Service. A Windows system that determines the IP address associated with a particular network device, also known as name resolution. WINS uses a distributed database that is automatically updated with the

NetBIOS

names of network devices currently available and the IP address assigned to each one.WINS provides a distributed database for registering and querying

dynamic NetBIOS names to IP address mapping in a routed network environment. It is the best choice

for

NetBIOS

name resolution in such a routed network because it is designed to solve the problems that occur with name resolution in complex networks.

X

X.509

A widely used standard for defining digital certificates. X.509 is actually an ITU recommendation, which means that it has not yet been officially defined or approved for standardized usage.

GL-22


OL-20339-01

xauth xlate

Glossary

See

IKE Extended Authentication

.

An xlate, also referred to as a translation entry, represents the mapping of one IP address to another, or the mapping of one IP address/port pair to another.

OL-20339-01


GL-23

Glossary

GL-24


OL-20339-01

Symbols

/bits subnet masks

A-3

Numerics

3H_Head3. Generating Syslog Messages in EMBLEM

Format to a Syslog Server

71-16

4GE SSM connector types

8-8

fiber

8-8

SFP

8-8

support

1-2

802.1Q tagging

8-19

802.1Q trunk

8-14

A

AAA

about

31-1

accounting

33-15

authentication

CLI access

32-11

network access

33-1

proxy limit

33-9

authorization command

32-13

downloadable access lists

33-10

network access

33-9

local database support

31-7

performance

33-1

server

71-4

adding

31-8, 31-10

OL-20339-01

I N D E X

types

31-3

support summary

31-3

web clients

33-5

AAA server group, add (group-policy)

64-6

ABR definition of

21-2

access_rules

17-3

Access Control Server

63-28

Access Group panel description

24-8

access lists downloadable

33-11

global access rules

30-4

implicit deny

30-3

inbound

30-3

outbound

30-3

overview

30-1

phone proxy

43-7

access ports

8-18

access rules turn off expansion

30-12

Accounting tab, tunnel group

64-88

ACE add/edit/paste

15-3, 64-17

Extended ACL tab

15-2, 64-16

ACL enabling IPSEC authenticated inbound sessions to bypass ACLs

64-101, 64-113

extended

15-2, 64-16

for Clientless SSL VPN

64-26

standard

15-1, 64-15

ACL Manager

Add/Edit/Paste ACE

15-3, 64-17


IN-1

Index

dialog box

15-1, 64-15

activation key

entering

4-24

location

4-22

obtaining

4-23

Active/Active failover about

60-1

actions

60-5

command replication

60-3

configuration synchronization

60-3

device initialization

60-3

duplicate MAC addresses, avoiding

60-2

optional settings about

60-6

primary status

60-2

secondary status

60-2

triggers

60-4

Active/Standby failover about

59-1

actions

59-4

command replication

59-3

configuration synchronization

59-2

device initialization

59-2

primary unit

59-2

secondary unit

59-2

triggers

59-3

Active Directory procedures

B-16 to ??

Adaptive Security Algorithm

1-18

Add/Edit Access Group dialog box description

24-8

Add/Edit Filtering Entry dialog box description

21-16

Add/Edit IGMP Join Group dialog box description

24-6

Add/Edit IGMP Static Group dialog box description

24-7

Add/Edit Multicast Group dialog box

24-14

description

24-14

Add/Edit OSPF Area dialog box

21-12


IN-2

description

21-12

Add/Edit OSPF Neighbor Entry dialog box

21-14, 21-15

description

21-15

Add/Edit Periodic Time Range dialog box

13-18

Add/Edit Rendezvous Point dialog box restrictions

24-11

Add/Edit Summary Address dialog box description

21-8, 21-12

Add/Edit Time Range dialog box

13-16

Add/Edit Virtual Link dialog box description

21-17

add_acl

17-3

address assignment, client

64-88

Address Pool panel, VPN wizard

62-12

address pools, tunnel group

64-88

Address Translation Exemption panel, VPN wizard

62-13

admin context about

6-2

administrative access using ICMP for

32-9

administrative distance

19-4

Advanced DHCP Options dialog box description

10-7

Advanced OSPF Interface Properties dialog box

21-11

Advanced OSPF Virtual Link Properties dialog box description

21-18

Advanced tab, tunnel group

64-89

ae_standard_access_list_rule

17-3

ae_webtype_acl

16-2

AIP SSC about

54-1

configuration

54-5

operating modes

54-2

sending traffic to

54-8

traffic flow

54-2

AIP SSM about

54-1

configuration

54-5

operating modes

54-2

OL-20339-01

port-forwarding enabling

8-22

sending traffic to

54-8

support

1-2

traffic flow

54-2

virtual sensors

54-7

alternate address, ICMP message

A-15

analyzing syslog messages

71-2

anti-replay window size

49-9, 63-11

APN, GTP application inspection

40-11

APPE command, denied request

37-22

application access and e-mail proxy

66-7

and Web Access

66-7

configuring client applications

66-6

enabling cookies on browser

66-6

privileges

66-6

quitting properly

66-6

setting up on client

66-6

using e-mail

66-7

with IMAP client

66-7

application firewall

37-30

application inspection

about

36-1

applying

36-5

configuring

36-5

security level requirements

8-5

Apply button

3-12

Area/Networks tab description

21-4

area border router

21-2

ARP

NAT

26-21

ARP inspection

about

5-8

enabling

5-10

static entry

5-9

ARP spoofing

5-8

ARP table

OL-20339-01

Index

monitoring

8-33

ARP test, failover

57-11

ASA (Adaptive Security Algorithm)

1-18

ASA 5505

Base license

8-2

client

Xauth

64-105

interfaces, about

8-1

MAC addresses

8-4

maximum VLANs

8-2

power over Ethernet

8-4

Security Plus license

8-2

SPAN

8-4

Spanning Tree Protocol, unsupported

8-18

ASA 5550 throughput

8-22

ASBR

definition of

21-2

asymmetric routing

TCP state bypass

48-4

attacks

DNS HINFO request

52-10

DNS request for all records

52-10

DNS zone transfer

52-10

DNS zone transfer from high port

52-10

fragmented ICMP traffic

52-9

IP fragment

52-7

IP impossible packet

52-7

large ICMP traffic

52-9

ping of death

52-9

proxied RPC request

52-10

statd buffer overflow

52-11

TCP FIN only flags

52-10

TCP NULL flags

52-9

TCP SYN+FIN flags

52-9

UDP bomb

52-10

UDP chargen DoS

52-10

UDP snork

52-10

attributes

RADIUS

B-30


IN-3

Index

Attributes Pushed to Client panel, VPN wizard

62-13

attribute-value pairs

TACACS+

B-39

authenticating a certificate

35-9

authentication about

31-2

CLI access

32-11

FTP

33-3

HTTP

33-2

network access

33-1

Telnet

33-2

web clients

33-5

Authentication tab description

21-9

authorization about

31-2

command

32-13


33-10

network access

33-9

Auto-MDI/MDIX

8-5

B

backed up configurations restoring

75-17

backing up configurations

75-13

Baltimore Technologies, CA server support

35-7

bandwidth

3-17

banner, view/configure

64-31

Basic tab

IPSec LAN-to-LAN, General tab

64-93

basic threat detection

See

threat detection

bits subnet masks

A-3

Botnet Traffic Filter actions

50-2

address categories

50-2

blacklist adding entries

50-8


IN-4

description

50-2

blocking traffic manually

50-12

classifying traffic

50-10

configuring

50-6

databases

50-2

default settings

50-6

DNS Reverse Lookup Cache

information about

50-3

maximum entries

50-4

using with dynamic database

50-9

DNS snooping

50-9

dropping traffic

50-10

graylist

50-10

dynamic database enabling use of

50-7

files

50-3

information about

50-2

searching

50-13

updates

50-7

feature history

50-15

graylist description

50-2

dropping traffic

50-10

guidelines and limitations

50-5

information about

50-1

licensing

50-5

monitoring

50-13

static database adding entries

50-8

information about

50-3

syslog messages

50-13

task flow

50-6

threat level dropping traffic

50-10

whitelist adding entries

50-8

description

50-2

working overview

50-4

broadcast Ping test

57-11

OL-20339-01

Browse ICMP

64-21

Browse Other

64-22

Browse Source or Destination Address

64-19

Browse Source or Destination Port

64-19

Browse Time Range

64-13

building blocks

13-1

bypassing firewall checks

48-3

C

CA certificate validation, not done in WebVPN

67-1

CRs and

35-3

public key cryptography

35-2

revoked certificates

35-3

supported servers

35-7

CA certificate

35-1

CA certificates

35-9

call agents

MGCP application inspection

38-17, 38-18

Cancel button

3-12

CDUP command, denied request

37-22

certificate

CA

35-9

Cisco Unified Mobility

45-5

Cisco Unified Presence

46-3

code-signer

35-20

Identity

35-14

local CA

35-22

certificate authentication

35-9

certificate enrollment

35-9

Certificate Revocation Lists

See

CRLs change query interval

24-9

change query response time

24-9

change query timeout value

24-9

changing the severity level

71-20

CIFS mount point accessing

75-4

OL-20339-01

Index

Cisco-AV-Pair LDAP attributes

B-13

Cisco Client Parameters tab

64-31

Cisco IOS CS CA server support

35-7

Cisco IP Communicator

43-9

Cisco IP Phones, application inspection

38-36

Cisco UMA. See Cisco Unified Mobility.


architecture

45-2

ASA role

41-2, 41-3, 42-2

certificate

45-5

functionality

45-1

NAT and PAT requirements

45-3, 45-4

trust relationship

45-5


ASA role

41-2, 41-3, 42-2

configuring the TLS Proxy

46-7


46-2

trust relationship

46-3

Cisco UP. See Cisco Unified Presence.

Class A, B, and C addresses

A-1

classes, logging

message class variables

71-4

types

71-4

classes, resource

See

resource management

class map regular expression

13-15

Client Access Rule, add or edit

64-28

Client Address Assignment

64-88

Client Authentication panel, VPN wizard

62-10

Client Configuration tab

64-29

Client Firewall tab

64-34

Clientless SSL VPN client application requirements

66-2

client requirements

66-2

for file management

66-5

for network browsing

66-5

for web browsing

66-4


IN-5

Index

start-up

66-3

enable cookies for

66-6

end user set-up

66-1

printing and

66-3

remote requirements

for port forwarding

66-6

for using applications

66-6

remote system configuration and end-user requirements

66-3

security tips

66-2

supported applications

66-2

supported browsers

66-3

supported types of Internet connections

66-3

URL

66-3

username and password required

66-3

usernames and passwords

66-1

use suggestions

66-1

client parameters, configuring

64-29

Client Update, edit , Windows and VPN 3002 clients

64-3

Client Update window, Windows and VPN 3002 clients

64-1

cluster mixed scenarios

63-21

code-signer certificate

35-20

command authorization about

32-13

configuring

32-13

multiple contexts

32-15

compiling syslog MIB files

73-8

configuration factory default

commands

2-5

restoring

2-5

configurations, backing up

75-13

configuring

CSC activation

56-4

CSC email

56-14

CSC file transfer

56-15

CSC IP address

56-5


IN-6

CSC license

56-4

CSC management access

56-6

CSC notifications

56-5

CSC password

56-7

CSC Setup Wizard

56-8, 56-11

CSC Setup Wizard Activation Codes

Configuration

56-9

CSC Setup Wizard Host Configuration

56-9

CSC Setup Wizard IP Configuration

56-9

CSC Setup Wizard Management Access

Configuration

56-10

CSC Setup Wizard Password Configuration

56-10

CSC Setup Wizard Summary

56-12

CSC Setup Wizard Traffic Selection for CSC

Scan

56-11

CSC updates

56-16

CSC Web

56-13

configuring mobile user security services

64-60

configuring MUS

64-60

connection limits configuring

48-1

per context

6-15

console port logging

71-15

contexts

See

security contexts conversion error, ICMP message

A-16

creating a custom event list

71-15

CRL cache refresh time

35-14

CSC

56-9

CSC activation configuring

56-4

CSC CPU monitoring

55-13

CSC email configuring

56-14

CSC file transfer configuring

56-15

CSC IP address configuring

56-5

OL-20339-01

CSC license configuring

56-4

CSC management access configuring

56-6

CSC memory monitoring

55-14

CSC notifications configuring

56-5

CSC password configuring

56-7

CSC security events monitoring

55-11

CSC Setup Wizard

56-8

activation codes configuratrion

56-9

Host configuratrion

56-9

IP configuratrion

56-9

management access configuratrion

56-10

password configuratrion

56-10

specifying traffic for CSC Scanning

56-11

summary

56-12

traffic selection for CSC Scan

56-11

CSC software updates monitoring

55-13

CSC SSM

about

55-1, 56-2

support

1-2

what to scan

55-3

CSC SSM feature history

55-15, 56-17

CSC SSM GUI configuring

56-13

CSC threats monitoring

55-11

CSC updates configuring

56-16

CSC Web configuring

56-13

customizing the end-user experience by the security appliance

67-88

custom messages list

OL-20339-01

Index

logging output destination

71-5

cut-through proxy

33-1

D

data flow routed firewall

5-14

transparent firewall

5-20

date and time in messages

71-20

default class

6-9

routes, defining equal cost routes

19-7

default configuration

commands

2-5

restoring

2-5

default policy

29-7

default routes about

19-7

configuring

19-7

default tunnel gateway

64-4

destination address, browse

64-19

destination port, browse

64-19

device ID, including in messages

71-19

device ID in messages

71-19

Device Pass-Through

64-106

DHCP configuring

10-5

monitoring interface lease

8-33

IP addresses

8-33

server

8-33

statistics

8-35

statistics

8-35


30-5

DHCP relay overview

10-2

DHCP Relay - Add/Edit DHCP Server dialog box description

10-4

restrictions

10-4


IN-7

Index

DHCP Relay pane description

10-2

DHCP Relay panel

10-2, 11-4

prerequisites

10-3

restrictions

10-3

DHCP Server pane description

10-5

DHCP Server panel

10-5

DHCP services

9-6

DiffServ preservation

49-5

digital certificates

35-1

directory hierarchy search

B-4

disabling content rewrite

67-17

disabling messages

71-20

disabling messages, specific message IDs

71-20

DMZ, definition

1-15

DNS inspection about

37-2

managing

37-1

rewrite, about

37-3

rewrite, configuring

37-3

NAT effect on

26-21

server, configuring

9-10

DNS HINFO request attack

52-10

DNS request for all records attack

52-10

DNS zone transfer attack

52-10

DNS zone transfer from high port attack

52-10

dotted decimal subnet masks

A-3

downloadable access lists configuring

33-11

converting netmask expressions

33-15

DSCP preservation

49-5

DUAL

23-2

dual IP stack, configuring

8-6

dual-ISP support

19-8

duplex interface

8-19, 8-20

duplex, configuring

8-8


IN-8

dynamic NAT about

26-8

network object NAT

27-3

twice NAT

28-3

dynamic PAT network object NAT

27-7

See also

NAT twice NAT

28-7

E

Easy VPN client

Xauth

64-105

Easy VPN, advanced properties

64-106

Easy VPN client

64-104

Easy VPN Remote

64-104

echo reply, ICMP message

A-15

Edit DHCP Relay Agent Settings dialog box description

10-4

prerequisites

10-4

restrictions

10-4

Edit DHCP Server dialog box description

10-6

Edit OSPF Interface Authentication dialog box

21-9

description

21-9

Edit OSPF Interface Properties dialog box

21-10

EIGRP

30-5

DUAL algorithm

23-2

hello interval

23-15

hello packets

23-1

hold time

23-2, 23-15

neighbor discovery

23-1

stub routing

23-5

stuck-in-active

23-2

e-mail proxy and Clientless SSL VPN

66-7

Enable IPSec authenticated inbound sessions

64-101,

64-113

OL-20339-01

enabling logging

71-6

enabling secure logging

71-19

enrolling certificate

35-9

Entrust, CA server support

35-7

established command, security level requirements

8-6

Ethernet

Auto-MDI/MDIX

8-5

duplex

8-8

jumbo frames, ASA 5580

8-32

jumbo frame support single mode

8-26

MTU

8-26

speed

8-8

EtherType access list

compatibilty with extended access lists

30-2

implicit deny

30-3

evaluation license

4-12

extended ACL

15-2, 64-16

External Group Policy, add or edit

64-6

F

factory default configuration commands

2-5

restoring

2-5

failover

about

57-1

about virtual MAC addresses

59-11

Active/Active,

See

Active/Active failover

Active/Standby,

See

Active/Standby failover configuration file terminal messages, Active/Active

60-3

terminal messages, Active/Standby

59-2

contexts

59-2

criteria

59-10, 60-12

debug messages

57-13

defining standby IP addresses

59-8, 59-9

disabling

59-12, 60-17

OL-20339-01

Index

enable

60-10

enabling Stateful Failover

59-7

Ethernet failover cable

57-3

failover link

57-3

forcing

59-12, 60-17

health monitoring

57-10

in multiple context mode

60-9

interface health

57-11

interface monitoring

57-11

interface tests

57-11

key

60-10

link communications

57-3

MAC addresses about

59-2

automatically assigning

6-11

monitoring, health

57-10

network tests

57-11

primary unit

59-2

redundant interfaces

8-12

reset

60-18

restoring a failed group

59-13, 60-17

restoring a failed unit

59-13, 60-17

secondary unit

59-2

SNMP syslog traps

57-13

Stateful Failover

60-11

Stateful Failover,

See

Stateful Failover state link

57-3

system log messages

57-13

system requirements

57-2

Trusted Flow Acceleration

7-2, 55-6, 56-3, 73-5

type selection

57-5

unit health

57-11

failover groups about

60-12

adding

60-13

editing

60-13

monitoring

60-19

reset

60-19

fast path

1-19


IN-9

Index

fiber interfaces

8-8

Fibre Channel interfaces default settings

16-2, 17-2, 30-7, 55-6, 56-3

filtering rules

34-6


8-5

servers supported

34-2

URLs

34-1, 34-2

filtering messages

71-4

Filtering panel description

21-16

firewall, client, configuring settings

64-34

firewall mode about

5-1

configuring

5-1

firewall server, Zone Labs

64-102

flash memory available for logs

71-18

flow control for 10 Gigabit Ethernet

8-10

flow-export actions

72-4

format of messages

71-3

fragmentation policy, IPsec

63-2

fragmented ICMP traffic attack

52-9

Fragment panel

52-2

fragment protection

1-16

fragment size

52-2

FTP application inspection

viewing

37-9, 37-18, 37-19, 37-31, 37-45, 37-52, 37-54,

38-7, 38-9, 38-17, 38-21, 38-29, 38-38, 38-40, 40-2, 40-14

filtering option

34-10

FTP inspection about

37-13

configuring

37-13

G

gateway, default tunnel gateway

64-4

gateways

MGCP application inspection

38-19


IN-10

General Client Parameters tab

64-29

graphs bookmarking

8-38

interface monitoring

8-38

printing

8-38

Group Policy window add or edit, General tab

64-7, 64-12

introduction

64-5

IPSec tab, add or edit

64-27

groups

GTP

SNMP

73-4

application inspection viewing

40-7

GTP inspection about

40-5

configuring

40-5

H

H.323

transparent firewall guidelines

5-3

H.323 inspection about

38-3

configuring

38-2

limitations

38-4

Hardware Client tab

64-36

HA Wizard accessing

58-1

licensing requirements

58-1

requirements for setup

58-2

Help button

3-12

HELP command, denied request

37-22

Help menu

3-9

hierarchical policy, traffic shaping and priority queueing

49-9

high availability about

57-1

history metrics

9-13

OL-20339-01

host

SNMP

73-4

hosts, subnet masks for

A-3

HSRP

5-3

HTTP application inspection viewing

37-30

filtering

34-1

HTTP(S) configuring

34-9

filtering

34-2

HTTP inspection

about

37-24

configuring

37-23

HTTPS/Telnet/SSH allowing network or host access to ASDM

32-1

I

ICMP add group

64-21

browse

64-21

rules for access to ADSM

32-9

testing connectivity

76-1

type numbers

A-15

ICMP Group

64-21

ICMP unreachable message limits

32-10

Identity Certificates

35-14

identity NAT

about

26-11

network object NAT

27-14

twice NAT

28-15

IKE Policy panel, VPN wizard

62-5

ILS inspection

39-1

IM

38-24

implementing SNMP

73-4

inbound access lists

30-3

individual syslog messages assigning or changing rate limits

71-21

OL-20339-01

Index

information reply, ICMP message

A-16

information request, ICMP message

A-16

inside, definition

1-15

inspection engines

See

application inspection

Instant Messaging inspection

38-24

interface duplex

8-19, 8-20

MTU

8-26

status

3-17

subinterface, adding

8-15

throughput

3-17

Interface panel

21-9

interfaces

ASA 5505 about

8-1

enabled status

8-18

MAC addresses

8-4

maximum VLANs

8-2

switch port configuration

8-18

trunk ports

8-19

ASA 5550 throughput

8-22

default settings

16-2, 17-2, 30-7, 55-6, 56-3

duplex

8-8

failover monitoring

57-11

fiber

8-8


8-26

MAC addresses automatically assigning

6-19

monitoring

8-36

redundant

8-12

SFP

8-8

speed

8-8

subinterfaces

8-14

intrusion prevention configuration

54-5

IP addresses classes

A-1

management, transparent firewall

9-14


IN-11

Index

private

A-2

subnet mask

A-4

IP audit enabling

52-5

signatures

52-6

IP fragment attack

52-7

IP fragment database, displaying

52-2

IP fragment database, editing

52-3

IP impossible packet attack

52-7

IP overlapping fragments attack

52-8

IP phone phone proxy provisioning

43-10

IP phones addressing requirements for phone proxy

43-8

supported for phone proxy

43-3

IPS

IP audit

52-5

See

AIP SSM or AIP SSC

IPSec

anti-replay window

49-9

IPsec

Cisco VPN Client

63-9

fragmentation policy

63-2

IPSec Encryption and Authentication panel, VPN wizard

62-6

IPSec rules anti-replay window size

49-9, 63-11

IPSec tab internal group policy

64-27

IPSec LAN-to-LAN

64-94

tunnel group

64-90

IP spoofing, preventing

52-1

IP teardrop attack

52-8

IPv6

commands

18-9

configuring alongside IPv4

8-6

default route

19-8

dual IP stack

8-6

duplicate address detection

7-21, 8-27, 25-6


IN-12

neighbor discovery

25-1

router advertisement messages

7-22, 25-8

static routes

19-8

IPv6 addresses

anycast

A-9

command support for

18-9

format

A-5

multicast

A-8

prefixes

A-10

required

A-10

types of

A-6

unicast

A-6

J

Java console

76-12

Join Group panel description

24-6

jumbo frames, ASA 5580

8-32


8-26

K

Kerberos configuring

31-8

support

31-6

key pairs

35-15

L

large ICMP traffic attack

52-9

latency about

49-1

configuring

49-2, 49-3

reducing

49-7

Layer 2 firewall

See


OL-20339-01

Index

Layer 2 forwarding table

See

MAC address table

Layer 3/4

matching multiple policy maps

29-5

LCS Federation Scenario

46-2

LDAP application inspection

39-1

attribute mapping

31-22

Cisco-AV-pair

B-13

configuring

31-8

configuring a AAA server

B-3 to ??

directory search

B-4

example configuration procedures

B-16 to ??

hierarchy example

B-4

licenses activation key entering

4-24

location

4-22

obtaining

4-23

ASA 5505

4-3

ASA 5510

4-4

ASA 5520

4-5

ASA 5540

4-6

ASA 5550

4-7

ASA 5580

4-8

Cisco Unified Communications Proxy features

41-4,

44-3, 45-6, 46-7, 47-8

default

4-12

evaluation

4-12

failover

4-21

guidelines

4-21

managing

4-1

preinstalled

4-12

Product Authorization Key

4-23

shared backup server, information

4-16

client, configuring

4-26

communication issues

4-16

failover

4-17

OL-20339-01

maximum clients

4-18

monitoring

4-27

overview

4-14

server, configuring

4-25

SSL messages

4-16

temporary

4-12

viewing current

4-23

VPN Flex

4-12


CSC SSM

55-5, 56-2

logging

71-5

licensing requirements for SNMP

73-4

link up/down test

57-11

LLQ

See

low-latency queue

load balancing mixed cluster scenarios

63-21

local CA

35-22

Local CA User Database

35-25

Local Hosts and Networks panel, VPN wizard

62-7

local user database support

31-7

lockout recovery

32-24

logging classes filtering messages by

71-4

types

71-4

filtering by message list

71-5

by severity level

71-1

output destinations internal buffer

71-1, 71-7


71-7

queue changing the size of

71-18

configuring

71-18

logging feature history

71-25

logging queue configuring

71-18


IN-13

Index

login banner, configuring

32-3

FTP

33-3

SSH

32-3

low-latency queue applying

49-2, 49-3

M

MAC address redundant interfaces

8-12

MAC addresses

ASA 5505

8-4

automatically assigning

6-19

failover

59-2

security context classification

6-3

MAC address table about

5-20

built-in-switch

5-11

MAC learning, disabling

5-13

monitoring

8-35

resource management

6-15

static entry

5-13


5-13

management interfaces default settings

16-2, 17-2, 30-7, 55-6, 56-3

management IP address, transparent firewall

9-14

man-in-the-middle attack

5-8

mapped addresses guidelines

26-20

mask reply, ICMP message

A-16

request, ICMP message

A-16

Master Passphrase

9-6

maximum sessions, IPSec

64-101

media termination address, criteria

43-5

menus

3-4

message filtering

71-4

message list


IN-14

filtering by

71-5

messages, logging classes about

71-4

list of

71-4

component descriptions

71-3

filtering by message list

71-5

format of

71-3

severity levels

71-3

messages classes

71-4

messages in EMBLEM format

71-16, 71-17

metacharacters, regular expression

13-11

MGCP application inspection configuring

38-18

viewing

38-16

MGCP inspection about

38-14

configuring

38-13

mgmt0 interfaces

default settings

16-2, 17-2, 30-7, 55-6, 56-3

MIBs

73-2

MIBs for SNMP

73-12

Microsoft Access Proxy

46-1

Microsoft client parameters, configuring

64-29

Microsoft Windows 2000 CA, supported

35-7

mixed cluster scenarios, load balancing

63-21

MMP inspection

45-1

mobile redirection, ICMP message

A-16

mode context

6-14

firewall

5-1

monitoring

ARP table

8-33

CSC CPU

55-13

CSC memory

55-14

CSC security events

55-11

CSC software updates

55-13

CSC SSM

55-10

OL-20339-01

CSC threats

55-11

DHCP interface lease

8-33

IP addresses

8-33

server

8-33

statistics

8-35

failover

57-10

failover groups

60-19

history metrics

9-13

interfaces

8-36

MAC address table

8-35

OSPF

21-20

SNMP

73-1

monitoring logging

71-22

monitoring NSEL

72-6

monitoring switch traffic, ASA 5505

8-4

MPF default policy

29-7

feature directionality

29-3

features

29-1

flows

29-5

matching multiple policy maps

29-5

See also

class map

See also

policy map

MPLS

LDP

30-6

router-id

30-6

TDP

30-6

MRoute panel description

24-4

MTU

8-26

multicast traffic

5-3

multiple context mode

logging

71-2

See

security contexts

MUS configuring

64-60

OL-20339-01

Index

N

NAT about

26-1

bidirectional initiation

26-2

disabling proxy ARP for global addresses

18-11

DNS

26-21

dynamic about

26-8

dynamic NAT

network object NAT

27-3

twice NAT

28-3

dynamic PAT about

26-10

network object NAT

27-7

twice NAT

28-7

identity about

26-11

identity NAT

network object NAT

27-14

twice NAT

28-15

implementation

26-15

interfaces

26-20

mapped address guidelines

26-20

network object comparison with twice NAT

26-15

network object NAT about

26-16

configuring

27-1

dynamic NAT

27-3

dynamic PAT

27-7

examples

27-17

guidelines

27-2

identity NAT

27-14

prerequisites

27-2

static NAT

27-11

routed mode

26-13

RPC not supported with

39-3

rule order

26-19


IN-15

Index


8-6

static about

26-3

few-to-many mapping

26-7

many-to-few mapping

26-6, 26-7

one-to-many

26-6

static NAT

network object NAT

27-11

twice NAT

28-11

static with port translation about

26-3

terminology

26-2

transparent mode

26-13

twice NAT about

26-16

comparison with network object NAT

26-15

configuring

28-1

dynamic NAT

28-3

dynamic PAT

28-7

examples

28-18

guidelines

28-2

identity NAT

28-15

prerequisites

28-2

static NAT

28-11

types

26-2

VPN client rules

26-19

NetBIOS server tab

64-68

NetFlow overview

72-1

NetFlow event matching to configured collectors

72-5

Netscape CMS, CA server support

35-7

Network Activity test

57-11

Network Admission Control uses, requirements, and limitations

63-27

network object NAT about

26-16

comparison with twice NAT

26-15


IN-16

configuring

27-1

dynamic NAT

27-3

dynamic PAT

27-7

examples

27-17

guidelines

27-2

identity NAT

27-14

prerequisites

27-2

static NAT

27-11

New Authentication Server Group panel, VPN wizard

62-11

NSEL and syslog messages redundant messages

72-2

NSEL feature history

72-8

NSEL licensing requirements

72-3

NTLM support

31-6

NT server configuring

31-8

support

31-6

O

object NAT

See

network object NAT open ports

A-14

Options menu

3-5

OSPF

area parameters

21-12

authentication support

21-2

configuring authentication

21-9

defining a static neighbor

21-14, 21-15

defining interface properties

21-10

interaction with NAT

21-2

interface parameters

21-9

interface properties

21-9, 21-10

link-state advertisement

21-2

logging neighbor states

21-16

LSAs

21-2

monitoring

21-20

NSSA

21-13

OL-20339-01

processes

21-2

redistributing routes

21-5

route calculation timers

21-15

route map

20-1

route summarization

21-8

OSPF parameters

dead interval

21-11

hello interval

21-11

retransmit interval

21-11

transmit delay

21-11

outbound access lists

30-3

Outlook Web Access (OWA) and Clientless SSL

VPN

66-7

output destination

71-5

output destinations

71-1, 71-7

e-mail address

71-1, 71-7

SNMP management station

71-1, 71-7

syslog server

71-7


71-1, 71-7

outside, definition

1-15

oversubscribing resources

6-8

P

packet classifier

6-3

packet flow routed firewall

5-14


5-20

packet trace, enabling

76-7

parameter problem, ICMP message

A-15

password

Clientless SSL VPN

66-1

PAT

See

dynamic PAT pause frames for flow control

8-10

PDP context, GTP application inspection

40-10

phone proxy

access lists

43-7

OL-20339-01

Index

ASA role

41-3

Cisco IP Communicator

43-9

Cisco UCM supported versions

43-3

IP phone addressing

43-8

IP phone provisioning

43-10

IP phones supported

43-3

Linksys routers, configuring

43-20


43-8

ports

43-7

rate limiting

43-10

PIM

TLS Proxy on ASA, described

41-3

ping shortest path tree settings

24-13

See

ICMP

using

76-3

ping of death attack

52-9

PoE

8-4

policy, QoS

49-1

policy map

Layer 3/4 about

29-1

feature directionality

29-3

flows

29-5

Port Forwarding

configuring client applications

66-6

port-forwarding enabling

8-22

port forwarding entry

67-22

ports open on device

A-14

phone proxy

43-7

TCP and UDP

A-11

port translation about

26-3

posture validation uses, requirements, and limitations

63-27

Posture Validation Exception, add/edit

63-29

power over Ethernet

8-4


IN-17

Index

PPP tab, tunnel-group

64-92

prerequisites for use

CSC SSM

55-5, 56-2

presence_proxy_remotecert

42-9

primary unit, failover

59-2

printing graphs

8-38

priority queueing hierarchical policy with traffic shaping

49-9

IPSec anti-replay window size

49-9, 63-11

private networks

A-2

Process Instances tab description

21-4

Product Authorization Key

4-23

Properties tab

21-10

description

21-10

fields

21-10

Protocol Group, add

64-22

protocol numbers and literal values

A-11

Protocol panel (PIM) description

24-10

proxied RPC request attack

52-10

proxy ARP

NAT

NAT

proxy ARP

26-21

proxy ARP, disabling

18-11

proxy bypass

67-28

proxy servers

SIP and

38-24

public key cryptography

35-2

Q

QoS about

49-1, 49-3

DiffServ preservation

49-5

DSCP preservation

49-5

feature interaction

49-4


IN-18

policies

49-1

priority queueing hierarchical policy with traffic shaping

49-9

IPSec anti-replay window

49-9

IPSec anti-replay window size

49-9, 63-11

token bucket

49-2

traffic shaping overview

49-4

Quality of Service

See

QoS queue, logging changing the size of

71-18

queue, QoS latency, reducing

49-7

limit

49-2, 49-3

R

RADIUS attributes

B-30

Cisco AV pair

B-13

configuring a AAA server

B-30

configuring a server

31-8


33-11

network access authentication

33-4

network access authorization

33-10

support

31-4

rate limit

71-20

rate limiting

49-3

rate limiting, phone proxy

43-10

RealPlayer

38-19

recurring time range, add or edit

64-14

redirect, ICMP message

A-15

redundant interfaces configuring

8-12

failover

8-12

MAC address

8-12

setting the active interface

8-14

Registration Authority description

35-3

OL-20339-01

regular expression

13-10

Remote Access Client panel, VPN wizard

62-8

Remote Site Peer panel, VPN wizard

62-4

Request Filter panel reset description

24-12

inbound connections

52-3

outside connections

52-3

Reset button

3-12

resource management

about

6-8

class

6-15

configuring

6-8

default class

6-9

oversubscribing

6-8

resource types

6-15

unlimited

6-9

restoring backups

75-17

revoked certificates

35-3

rewrite, disabling

67-17

RFCs for SNMP

73-12

RIP authentication

22-1

definition of

22-1

enabling

22-4

support for

22-1

RIP panel limitations

22-3

RIP Version 2 Notes

22-3

RNFR command, denied request

37-22

RNTO command, denied request

37-22

routed mode

about

5-1

NAT

26-13

setting

5-1

route maps uses

20-1

router

advertisement, ICMP message

A-15

OL-20339-01

Index

solicitation, ICMP message

A-15

routes about default

19-7

configuring default routes

19-7

configuring IPv6 default

19-8

configuring IPv6 static

19-8

configuring static routes

19-3

Route Summarization tab description

21-4

Route Tree panel

24-13

description

24-13

routing

RSA other protocols

30-5

KEON, CA server support

35-7

RTSP inspection about

38-19

configuring

38-19

rules

ICMP

32-9

S

same security level communication enabling

8-31

SCCP (Skinny) inspection about

38-36

configuration

38-36

configuring

38-36

SDI configuring

31-8

support

31-5

secondary unit, failover

59-2

Secure Computing SmartFilter filtering server

34-3

Secure Copy configure server

32-6

security, WebVPN

67-1

security appliance

managing licenses

4-1


IN-19

Index

security contexts about

6-1

adding

6-17

admin context about

6-2

cascading

6-6

classifier

6-3

command authorization

32-15

logging in

6-7

MAC addresses automatically assigning

6-19

classifying using

6-3

managing

6-1

monitoring

6-20

multiple mode, enabling

6-14

nesting or cascading

6-7

resource management

6-8

unsupported features

6-12

security level about

8-5

security models for SNMP

73-3

segment size maximum and minimum

52-3

sending messages to an e-mail address

71-12

sending messages to a specified output destination

71-19

sending messages to a syslog server

71-7

sending messages to a Telnet or SSH session

71-15

sending messages to the console port

71-15

sending messages to the internal log buffer

71-11

Server and URL List add/edit

64-39

Server or URL dialog box

64-39

session management path

1-18

severity levels, of system log messages

changing

71-1

filtering by

71-1

list of

71-3

severity levels, of system messages


IN-20

definition

71-3

shared license backup server, information

4-16

client, configuring

4-26

communication issues

4-16

failover

4-17

maximum clients

4-18

monitoring

4-27

server, configuring

4-25

SSL messages

4-16

shun duration

51-10

signatures attack and informational

52-6

single mode backing up configuration

6-14

configuration

6-14

enabling

6-14

restoring

6-14

SIP inspection about

38-24

configuring

38-23

instant messaging

38-24

SITE command, denied request

37-22

SMTP inspection

37-50

SNMP about

73-1

application inspection viewing

40-17

failover

73-5

management station

71-1, 71-7

prerequisites

73-5

SNMP configuration

73-6

SNMP groups

73-4

SNMP hosts

73-4

SNMP management station adding

73-6

SNMP monitoring

73-10, 73-11, 74-5

SNMP terminology

73-2

OL-20339-01

SNMP traps

73-2

SNMP users

73-4

SNMP Version 3

73-3, 73-9

SNMP Versions 1 and 2c

73-9

software version

3-23

source address, browse

64-19

source port, browse

64-19

source quench, ICMP message

A-15

SPAN

8-4

Spanning Tree Protocol, unsupported

8-18

specifying traffic for CSC scanning

56-11

speed, configuring

8-8

SSCMs configuration

AIP SSC

54-5

SSCs

management access

53-2

management defaults

53-4

management interface

53-4

password reset

53-6

routing

53-3

SSH supported applications

53-1

concurrent connections

32-2

login

32-3

username

32-3

SSMs configuration

AIP SSM

54-5

management access

53-2

management defaults

53-4

password reset

53-6

routing

53-3

supported applications

53-1

Standard Access List Rule, add/edit

64-33

Standard ACL tab

15-1, 64-15

Startup Wizard acessing

7-1

OL-20339-01

Index


7-1, 42-3

requirements for setup

7-2

statd buffer overflow attack

52-11

Stateful Failover about

57-6

enabling

59-7

settings

60-11

state information

57-7

state link

57-3

stateful inspection

1-18

bypassing

48-3

state information

57-7

state link

57-3

static ARP entry

5-9

static bridge entry

5-13

Static Group panel description

24-7

static NAT about

26-3

few-to-many mapping

26-7

many-to-few mapping

26-6, 26-7

network object NAT

27-11

twice NAT

28-11

static NAT with port translation about

26-3

static routes configuring

19-3

deleting

19-6

status bar

3-11

stealth firewall

See


STOU command, denied request

37-22

stuck-in-active

23-2

subinterface adding

8-15

subinterfaces, adding

8-14

subnet masks

/bits

A-3

about

A-2


IN-21

Index

address range

A-4

determining

A-3

dotted decimal

A-3

number of hosts

A-3

subordinate certificate

35-1

Summary Address panel description

21-7

Summary panel, VPN wizard

62-14

Sun Microsystems Java™ Runtime Environment (JRE) and Clientless SSL VPN

66-6

Sun RPC inspection about

39-3

configuring

39-3

switch MAC address table

5-11

switch ports access ports

8-18

SPAN

8-4

trunk ports

8-19

syslogd server program

71-5

syslog message filtering using log viewers

71-22

syslog messages analyzing

71-2

syslog messaging for SNMP

73-11

syslog server as output destination designating more than one

71-5

EMBLEM format configuring

71-17

system configuration

6-2

system log messages classes

71-4

classes of

71-4

configuring in groups by message list

71-5

by severity level

71-1

device ID, including

71-19

disabling logging of

71-1

filtering by message class

71-4


IN-22

output destinations

71-1, 71-7

syslog message server

71-7


71-7

severity levels about

71-3

changing the severity level of a message

71-1

timestamp, including

71-20

T

TACACS+ command authorization, configuring

32-18

configuring a server

31-8

network access authorization

33-9

support

31-5

tail drop

49-3

TCP connection limits per context

6-15

maximum segment size

52-3

ports and literal values

A-11

TIME_WAIT state

52-4

TCP FIN only flags attack

52-10

TCP Intercept statistics

51-6

TCP normalization

48-3

TCP NULL flags attack

52-9

TCP Service Group, add

64-20

TCP state bypass

AAA

48-5

configuring

48-8

failover

48-5

firewall mode

48-5

inspection

48-5

mutliple context mode

48-5

NAT

48-5

SSMs and SSCs

48-5

TCP Intercept

48-5

TCP normalization

48-5


48-5

OL-20339-01

TCP SYN+FIN flags attack

52-9

Telnet allowing management access

32-1

concurrent connections

32-2

temporary license

4-12

testing configuration

76-1

threat detection basic

drop types

51-2

enabling

51-4

overview

51-2

rate intervals

51-2

statistics, viewing

51-4

system performance

51-2

scanning enabling

51-10

host database

51-9

overview

51-8

shunning attackers

51-10

system performance

51-9

scanning statistics enabling

51-5

system performance

3-20, 51-5

viewing

51-7

shun duration

51-10

TIME_WAIT state

52-4

time exceeded, ICMP message

A-15

time range add or edit

64-14

browse

64-13

recurring

64-14

timestamp, including in system log messages

71-20

timestamp reply, ICMP message

A-15

timestamp request, ICMP message

A-15

TLS Proxy applications supported by ASA

41-3

Cisco Unified Presence architecture

46-1

configuring for Cisco Unified Presence

46-7

OL-20339-01

Index

licenses

41-4, 44-3, 45-6, 46-7, 47-8

tocken bucket

49-2

Tools menu

3-6

traceroute, enabling

3-7, 76-6

traffic flow routed firewall

5-14


5-20

traffic shaping overview

49-4

transmit queue ring limit

49-2, 49-3

transparent firewall about

5-2

ARP inspection about

5-8

enabling

5-10

static entry

5-9

data flow

5-20

DHCP packets, allowing

30-5

guidelines

5-5

H.323 guidelines

5-3

HSRP

5-3


5-13

Management 0/0 IP address

8-22

management IP address

9-14

multicast traffic

5-3

packet handling

30-5

static bridge entry

5-13


5-6

VRRP

5-3

transparent mode

NAT

26-13

trunk, 802.1Q

8-14

trunk ports

8-19

Trusted Flow Acceleration failover

7-2, 55-6, 56-3

modes

5-5, 5-9, 5-12, 7-2, 19-2, 20-3, 21-3, 22-3, 23-2, 24-3,

25-18, 30-7, 55-6, 56-3, 58-2, 60-7

trustpoint

35-4

trust relationship


IN-23

Index


45-5


46-3

Tunneled Management

64-106

tunnel gateway, default

64-4

twice NAT about

26-16

comparison with network object NAT

26-15

configuring

28-1

dynamic NAT

28-3

dynamic PAT

28-7

examples

28-18

guidelines

28-2

identity NAT

28-15

prerequisites

28-2

static NAT

28-11

tx-ring-limit

49-2, 49-3

U

UDP bomb attack

52-10

chargen DoS attack

52-10

connection limits per context

6-15

connection state information

1-19

ports and literal values

A-11

snork attack

52-10

unreachable, ICMP message

A-15

unreachable messages

URL required for MTU discovery

32-9

filtering configuring

34-9

URLs filtering

34-1

filtering, about

34-2

User Accounts panel, VPN wizard

62-11

username

Clientless SSL VPN

66-1

Xauth for Easy VPN client

64-105


IN-24

users

SNMP

73-4

V

VeriSign, configuring CAs example

35-7

version

IPS software

3-23

View/Config Banner

64-31

virtual firewalls

See

security contexts virtual HTTP

33-3

Virtual Link description

21-17

virtual MAC address

defining for Active/Active failover

60-15

virtual MAC addresses about

59-11, 60-15

defaults for Active/Active failover

60-15

defining for Active/Standby failover

60-16

virtual private network overview

62-2

virtual reassembly

1-16

virtual sensors

54-7

VLANs

8-14

802.1Q trunk

8-14

ASA 5505

MAC addresses

8-4

maximum

8-2

subinterfaces

8-14

VoIP

proxy servers

38-24

VPN address range, subnets

A-4

overview

62-1, 62-2

system options

64-101

VPN client

NAT rules

26-19

VPN Client, IPsec attributes

63-9

OL-20339-01

Index

VPN flex license

4-12

VPN Tunnel Type panel, VPN wizard

62-3

VPN wizard

62-2

Address Pool panel

62-12

Address Translation Exemption panel

62-13

Attributes Pushed to Client panel

62-13

Client Authentication panel

62-10

IKE Policy panel

62-5

IPSec Encryption and AUthentication panel

62-6

Remote Access Client panel

62-8

Remote Site Peer panel

62-4

Summary panel

62-14

User Accounts panel

62-11

VPN Tunnel Type panel

62-3

VPNwizard

Local Hosts and Networks panel

62-7

New Authentication Server Group panel

62-11

VRRP

5-3

W

WCCP

12-1

web browsing with Clientless SSL VPN

66-4

web caching

12-1

web clients, secure authentication

33-5

Websense filtering server

34-3

WebVPN

CA certificate validation not done

67-1

security preautions

67-1

use suggestions

66-2

Window menu

3-9

Wizards menu

3-8

X

Xauth, Easy VPN client

64-105

XOFF frames

8-10

Z

Zone Labs Integrity Server

64-102

OL-20339-01


IN-25

Index

IN-26


OL-20339-01