MPLS Layer 3 VPNs Inter-AS and CSC 12.4T Americas Headquarters

MPLS Layer 3 VPNs Inter-AS and CSC 12.4T Americas Headquarters
MPLS Layer 3 VPNs Inter-AS and CSC
Configuration Guide, Cisco IOS Release
12.4T
Americas Headquarters
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CONTENTS
MPLS VPN Carrier Supporting Carrier with BGP 1
Finding Feature Information 1
Prerequisites for MPLS VPN CSC with BGP 1
Restrictions for MPLS VPN CSC with BGP 2
Information About MPLS VPN CSC with BGP 2
MPLS VPN CSC Introduction 2
Benefits of Implementing MPLS VPN CSC 2
Benefits of Implementing MPLS VPN CSC with BGP 3
Configuration Options for MPLS VPN CSC with BGP 3
Customer Carrier Is an ISP with an IP Core 3
Customer Carrier Is an MPLS Service Provider With or Without VPN Services 4
How to Configure MPLS VPN CSC with BGP 5
Identifying the Carrier Supporting Carrier Topology 5
What to Do Next 6
Configuring the Backbone Carrier Core 6
Prerequisites 6
Verifying IP Connectivity and LDP Configuration in the CSC Core 6
Troubleshooting Tips 8
Configuring VRFs for CSC-PE Routers 9
Troubleshooting Tips 11
Configuring Multiprotocol BGP for VPN Connectivity in the Backbone Carrier 11
Troubleshooting Tips 13
Configuring the CSC-PE and CSC-CE Routers 13
Configuring CSC-PE Routers 13
Troubleshooting Tips 15
Configuring CSC-CE Routers 16
Verifying Labels in the CSC-PE Routers 18
Verifying Labels in the CSC-CE Routers 20
Configuring the Customer Carrier Network 22
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Prerequisites 22
Verifying IP Connectivity in the Customer Carrier 22
Configuring a Customer Carrier Core Router as a Route Reflector 23
Troubleshooting Tips 25
Configuring the Customer Site for Hierarchical VPNs 26
Defining VPNs on PE Routers for Hierarchical VPNs 26
Configuring BGP Routing Sessions on the PE Routers for Hierarchical VPNs 28
Verifying Labels in Each PE Router for Hierarchical VPNs 29
Configuring CE Routers for Hierarchical VPNs 30
Verifying IP Connectivity in the Customer Site 32
Configuration Examples for MPLS VPN CSC with BGP 34
Configuring the Backbone Carrier Core Examples 35
Verifying IP Connectivity and LDP Configuration in the CSC Core Example 35
Configuring VRFs for CSC-PE Routers Example 37
Configuring Multiprotocol BGP for VPN Connectivity in the Backbone Carrier
Example 37
Configuring the Links Between CSC-PE and CSC-CE Routers Examples 37
Configuring the CSC-PE Routers Examples 38
Configuring the CSC-CE Routers Examples 38
Verifying Labels in the CSC-PE Routers Examples 39
Verifying Labels in the CSC-CE Routers Examples 41
Configuring the Customer Carrier Network Examples 43
Verifying IP Connectivity in the Customer Carrier Example 43
Configuring a Customer Carrier Core Router as a Route Reflector Example 44
Configuring the Customer Site for Hierarchical VPNs Examples 44
Configuring PE Routers for Hierarchical VPNs Examples 44
Verifying Labels in Each PE Router for Hierarchical VPNs Examples 45
Configuring CE Routers for Hierarchical VPNs Examples 46
Verifying IP Connectivity in the Customer Site Examples 47
Additional References 47
Feature Information for MPLS VPN CSC with BGP 49
Glossary 49
MPLS VPN Carrier Supporting Carrier Using LDP and an IGP 53
Finding Feature Information 53
Prerequisites for MPLS VPN CSC with LDP and IGP 53
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Restrictions for MPLS VPN CSC with LDP and IGP 54
Information About MPLS VPN CSC with LDP and IGP 55
MPLS VPN CSC Introduction 55
Benefits of Implementing MPLS VPN CSC 55
Configuration Options for MPLS VPN CSC with LDP and IGP 56
Customer Carrier Is an ISP 56
Customer Carrier Is a BGP MPLS VPN Service Provider 59
How to Configure MPLS VPN CSC with LDP and IGP 61
Configuring the Backbone Carrier Core 61
Prerequisites 61
Verifying IP Connectivity and LDP Configuration in the CSC Core 61
Troubleshooting Tips 63
Configuring VRFs for CSC-PE Routers 64
Troubleshooting Tips 66
Configuring Multiprotocol BGP for VPN Connectivity in the Backbone Carrier 66
Troubleshooting Tips 68
Configuring the CSC-PE and CSC-CE Routers 68
Prerequisites 68
Configuring LDP on the CSC-PE and CSC-CE Routers 68
Enabling MPLS Encapsulation on the CSC-PE and CSC-CE Routers 70
Verifying the Carrier Supporting Carrier Configuration 71
Configuration Examples for MPLS VPN CSC with LDP and IGP 72
MPLS VPN CSC Network with a Customer Who Is an ISP Example 72
CSC-CE1 Configuration 73
CSC-PE1 Configuration 73
CSC-PE2 Configuration 75
CSC-CE2 Configuration 76
MPLS VPN CSC Network with a Customer Who Is an MPLS VPN Provider Example 77
CE1 Configuration 77
PE1 Configuration 78
CSC-CE1 Configuration 79
CSC-PE1 Configuration 80
CSC-PE2 Configuration 81
CSC-CE2 Configuration 82
PE2 Configuration 83
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CE2 Configuration 84
MPLS VPN CSC Network That Contains Route Reflectors Example 85
Backbone Carrier Configuration 86
Route Reflector 1 (72K-37-1) Configuration 86
Route Reflector 2 (72K-38-1) Configuration 87
CSC-PE1 (75K-37-3) Configuration 88
CSC-PE2 (75K-38-3) Configuration 89
Customer Carrier Site 1 Configuration 91
PE1 (72K-36-8) Configuration 91
CSC-CE1 (72K-36-9) Configuration 92
PE2 (72K-36-7) Configuration 93
Route Reflector 3 (36K-38-4) Configuration 94
CE1 (36K-36-1) Configuration 95
Customer Carrier Site 2 Configuration 95
CSC-CE3 (72K-36-6) Configuration 96
PE3 (72K-36-4) Configuration 96
CSC-CE4 (72K-36-5) Configuration 98
Route Reflector 4 (36K-38-5) Configuration 98
CE2 (36K-36-2) Configuration 99
CE3 (36K-36-3) Configuration 99
MPLS VPN CSC Network with a Customer Who Has VPNs at the Network Edge Example 101
Backbone Carrier Configuration 101
CSC-PE1 (72K-36-9) Configuration 102
P1 (75K-37-3) Configuration 103
P2 (75K-38-3) Configuration 105
CSC-PE2 (72K-36-5) Configuration 106
Customer Carrier Site 1 Configuration 108
CSC-CE1 (72K-36-8) Configuration 108
PE2 (72K-36-7) Configuration 109
CE1 (36K-36-1) Configuration 110
Customer Carrier Site 2 Configuration 110
CSC-CE2 (72K-36-4) Configuration 110
PE2 (72K-36-6) Configuration 111
CE2 (36K-38-4) Configuration 113
CE3 (36K-38-5) Configuration 113
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Additional References 114
Feature Information for MPLS VPN CSC with LDP and IGP 115
Glossary 116
MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses 119
Finding Feature Information 119
Prerequisites for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses 119
Restrictions for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses 121
Information About MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses 121
MPLS VPN Inter-AS Introduction 121
Benefits of MPLS VPN Inter-AS 121
Use of Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses 122
Information Exchange in an MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4
Addresses 122
Transmission of Information in an MPLS VPN Inter-AS with ASBRs Exchanging VPNIPv4 Addresses 122
Exchange of VPN Routing Information in an MPLS VPN Inter-AS with ASBRs
Exchanging VPN-IPv4 Addresses 124
Packet Forwarding Between MPLS VPN Inter-AS Systems with ASBRs Exchanging VPNIPv4 Addresses 126
Use of a Confederation for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4
Addresses 128
How to Configure MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses 129
Configuring the ASBRs to Exchange VPN-IPv4 Addresses 130
Configuring EBGP Routing to Exchange VPN Routes Between Subautonomous Systems in a
Confederation 131
Verifying Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses 134
Configuration Examples for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses 135
Configuring MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses Example 136
Configuration for Autonomous System 1 CE1 Example 136
Configuration for Autonomous System 1 PE1 Example 137
Configuration for Autonomous System 1 P1 Example 138
Configuration for Autonomous System 1 EBGP1 Example 138
Configuration for Autonomous System 2 EBGP2 Example 139
Configuration for Autonomous System 2 P2 Example 140
Configuration for Autonomous System 2 PE2 Example 141
Configuration for Autonomous System 2 CE2 Example 142
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Configuring MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses in a
Confederation Example 143
Configuration for Autonomous System 1 CE1 Example 143
Configuration for Autonomous System 1 PE1 Example 144
Configuration for Autonomous System 1 P1 Example 145
Configuration for Autonomous System 1 ASBR1 Example 145
Configuration for Autonomous System 2 ASBR2 Example 146
Configuration for Autonomous System 2 P2 Example 147
Configuration for Autonomous System 2 PE2 Example 148
Configuration for Autonomous System 2 CE2 Example 149
Additional References 150
Feature Information for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses 151
MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels 153
Finding Feature Information 153
Prerequisites for MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS
Labels 154
Restrictions for MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels
155
Information About MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS
Labels 155
MPLS VPN Inter-AS Introduction 155
Benefits of MPLS VPN Inter-AS 156
Information About Using MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and
MPLS Labels 156
Benefits of MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels 156
How the Inter-AS Works When ASBRs Exchange IPv4 Routes with MPLS Labels 157
BGP Routing Information 157
Types of BGP Messages and MPLS Labels 158
How BGP Sends MPLS Labels with Routes 158
How to Configure MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS
Labels 158
Configuring the ASBRs to Exchange IPv4 Routes and MPLS Labels 159
Configuring the Route Reflectors to Exchange VPN-IPv4 Routes 161
Configuring the Route Reflector to Reflect Remote Routes in Its Autonomous System 163
Verifying the MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS
Labels Configuration 166
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Verifying the Route Reflector Configuration 167
Verifying that CE1 Can Communicate with CE2 168
Verifying that PE1 Can Communicate with CE2 169
Verifying that PE2 Can Communicate with CE2 171
Verifying the ASBR Configuration 172
Verifying the ASBR Configuration 173
Configuration Examples for MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and
MPLS Labels 174
Configuring MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels
over an MPLS VPN Service Provider Examples 174
Route Reflector 1 Configuration Example (MPLS VPN Service Provider) 174
ASBR1 Configuration Example (MPLS VPN Service Provider) 176
Route Reflector 2 Configuration Example (MPLS VPN Service Provider) 177
ASBR2 Configuration Example (MPLS VPN Service Provider) 177
Configuring MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels
over a Non-MPLS VPN Service Provider Examples 179
Route Reflector 1 Configuration Example (Non-MPLS VPN Service Provider) 179
ASBR1 Configuration Example (Non-MPLS VPN Service Provider) 180
Route Reflector 2 Configuration Example (Non-MPLS VPN Service Provider) 182
ASBR2 Configuration Example (Non-MPLS VPN Service Provider) 182
ASBR3 Configuration Example (Non-MPLS VPN Service Provider) 183
Route Reflector 3 Configuration Example (Non-MPLS VPN Service Provider) 185
ASBR4 Configuration Example (Non-MPLS VPN Service Provider) 185
Additional References 186
Feature Information for MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS
Labels 188
Load Sharing MPLS VPN Traffic 191
Finding Feature Information 191
Prerequisites for Load Sharing MPLS VPN Traffic 191
Restrictions for Load Sharing MPLS VPN Traffic 191
Information About Load Sharing MPLS VPN Traffic 194
Overview of Load Sharing Using BGP Multipath Options 194
Internal BGP Multipath Load Sharing 194
BGP Multipath for eBGP and iBGP 194
eBGP and iBGP Multipath Load Sharing in an MPLS Network Using BGP 195
eBGP and iBGP Multipath Load Sharing with Route Reflectors 195
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eBGP Multipath Load Sharing 196
Load Sharing Using Directly Connected Loopback Peering 196
How to Configure Load Sharing 197
Configuring BGP Multipath Load Sharing for eBGP and iBGP 197
Verifying BGP Multipath Load Sharing for eBGP and iBGP 198
Configuring eBGP Multipath Load Sharing with MPLS VPN Inter-AS 199
Configuring eBGP Multipath Load Sharing with MPLS VPN Carrier Supporting Carrier on
the CSC-PE Routers 201
Configuring eBGP Multipath Load Sharing with MPLS VPN Carrier Supporting Carrier on
the CSC-CE Routers 203
Configuring DCLP for MPLS VPN Inter-AS using ASBRs to Exchange VPN-IPv4
Addresses 206
Configuring Loopback Interface Addresses for Directly Connected ASBRs 206
Configuring 32 Static Routes to the eBGP Neighbor Loopback 207
Configuring Forwarding on Connecting Loopback Interfaces 209
Configuring an eBGP Session Between the Loopbacks 210
Verifying That Load Sharing Occurs Between Loopbacks 213
Configuring DCLP for MPLS VPN Inter-AS Using ASBRs to Exchange IPv4 Routes and
Labels 213
Configuring Loopback Interface Addresses for Directly Connected ASBRs 214
Configuring 32 Static Routes to the eBGP Neighbor Loopback 215
Configuring Forwarding on Connecting Loopback Interfaces 216
Configuring an eBGP Session Between the Loopbacks 217
Verifying That Load Sharing Occurs Between Loopbacks 220
Configuring Directly Connected Loopback Peering on MPLS VPN Carrier Supporting
Carrier 221
Configuring Loopback Interface Addresses on CSC-PE Routers 221
Configuring Loopback Interface Addresses for CSC-CE Routers 223
Configuring 32 Static Routes to the eBGP Neighbor Loopback on the CSC-PE Router 224
Configuring 32 Static Routes to the eBGP Neighbor Loopback on the CSC-CE Router 225
Configuring Forwarding on CSC-PE Interfaces That Connect to the CSC-CE Loopback 226
Configuring Forwarding on CSC-CE Interfaces That Connect to the CSC-PE Loopback 228
Configuring an eBGP Session Between the CSC-PE Router and the CSC-CE Loopback 229
Configuring an eBGP Session Between the CSC-CE Router and the CSC-PE Loopback 232
Verifying That Load Sharing Occurs Between Loopbacks 234
Configuration Examples for Load Sharing MPLS VPN Traffic 235
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Configuring a Router to Select eBGP or iBGP Paths as Multipaths Example 236
Configuring a 32 Static Route from an ASBR to the Loopback Address of Another ASBR
Examples 236
Configuring BGP MPLS Forwarding on the Interfaces Connecting ASBRs Example 236
Configuring VPNv4 Sessions on an ASBR Example 236
Verifying VPN NLRI for a Specified Network Example 237
Additional References 237
Feature Information for Load Sharing MPLS VPN Traffic 239
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MPLS VPN Carrier Supporting Carrier with
BGP
Multiprotocol Label Switching (MPLS) Virtual Private Network (VPN) Carrier Supporting Carrier (CSC)
enables one MPLS VPN-based service provider to allow other service providers to use a segment of its
backbone network. This module explains how to configure an MPLS VPN CSC network that uses Border
Gateway Protocol (BGP) to distribute routes and MPLS labels.
•
•
•
•
•
•
•
•
•
Finding Feature Information, page 1
Prerequisites for MPLS VPN CSC with BGP, page 1
Restrictions for MPLS VPN CSC with BGP, page 2
Information About MPLS VPN CSC with BGP, page 2
How to Configure MPLS VPN CSC with BGP, page 5
Configuration Examples for MPLS VPN CSC with BGP, page 34
Additional References, page 47
Feature Information for MPLS VPN CSC with BGP, page 49
Glossary, page 49
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest feature
information and caveats, see the release notes for your platform and software release. To find information
about the features documented in this module, and to see a list of the releases in which each feature is
supported, see the Feature Information Table at the end of this document.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support.
To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Prerequisites for MPLS VPN CSC with BGP
•
•
You should be able to configure MPLS VPNs with end-to-end (CE-to-CE router) pings working. To
accomplish this, you need to know how to configure Interior Gateway Protocols (IGPs), MPLS Label
Distribution Protocol (LDP), and Multiprotocol Border Gateway Protocol (MP-BGP).
Make sure that the CSC-PE routers and the CSC-CE routers run images that support BGP label
distribution. Otherwise, you cannot run external BGP (EBGP) between them. Ensure that connectivity
between the customer carrier and the backbone carrier. EBGP-based label distribution is configured on
these links to enable MPLS between the customer and backbone carriers.
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MPLS VPN CSC Introduction
Restrictions for MPLS VPN CSC with BGP
Restrictions for MPLS VPN CSC with BGP
On a provider edge (PE) router, you can configure an interface for either BGP with labels or LDP. You
cannot enable both types of label distribution on the same interface. If you switch from one protocol to the
other, then you must disable the existing protocol on all interfaces before enabling the other protocol.
This feature does not support the following:
•
•
EBGP multihop between CSC-PE and CSC-CE routers
EIBGP multipath load sharing
The physical interfaces that connect the BGP speakers must support Cisco Express Forwarding or
distributed Cisco Express Forwarding and MPLS.
Information About MPLS VPN CSC with BGP
•
•
•
•
MPLS VPN CSC Introduction, page 2
Benefits of Implementing MPLS VPN CSC, page 2
Benefits of Implementing MPLS VPN CSC with BGP, page 3
Configuration Options for MPLS VPN CSC with BGP, page 3
MPLS VPN CSC Introduction
Carrier supporting carrier is where one service provider allows another service provider to use a segment of
its backbone network. The service provider that provides the segment of the backbone network to the other
provider is called the backbone carrier. The service provider that uses the segment of the backbone network
is called the customer carrier.
A backbone carrier offers Border Gateway Protocol and Multiprotocol Label Switching (BGP/MPLS) VPN
services. The customer carrier can be either:
•
•
An Internet service provider (ISP)
A BGP/MPLS VPN service provider
Benefits of Implementing MPLS VPN CSC
The MPLS VPN CSC network provides the following benefits to service providers who are backbone
carriers and to customer carriers.
Benefits to the Backbone Carrier
•
•
The backbone carrier can accommodate many customer carriers and give them access to its backbone.
The backbone carrier does not need to create and maintain separate backbones for its customer
carriers. Using one backbone network to support multiple customer carriers simplifies the backbone
carrier’s VPN operations. The backbone carrier uses a consistent method for managing and
maintaining the backbone network. This is also cheaper and more efficient than maintaining separate
backbones.
The MPLS VPN carrier supporting carrier feature is scalable. Carrier supporting carrier can change the
VPN to meet changing bandwidth and connectivity needs. The feature can accommodate unplanned
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Benefits of Implementing MPLS VPN CSC with BGP
Customer Carrier Is an ISP with an IP Core
•
growth and changes. The carrier supporting carrier feature enables tens of thousands of VPNs to be set
up over the same network, and it allows a service provider to offer both VPN and Internet services.
The MPLS VPN carrier supporting carrier feature is a flexible solution. The backbone carrier can
accommodate many types of customer carriers. The backbone carrier can accept customer carriers who
are ISPs or VPN service providers or both. The backbone carrier can accommodate customer carriers
that require security and various bandwidths.
Benefits to the Customer Carriers
•
•
•
•
The MPLS VPN carrier supporting carrier feature removes from the customer carrier the burden of
configuring, operating, and maintaining its own backbone. The customer carrier uses the backbone
network of a backbone carrier, but the backbone carrier is responsible for network maintenance and
operation.
Customer carriers who use the VPN services provided by the backbone carrier receive the same level
of security that Frame Relay or ATM-based VPNs provide. Customer carriers can also use IPSec in
their VPNs for a higher level of security; it is completely transparent to the backbone carrier.
Customer carriers can use any link layer technology (SONET, DSL, Frame Relay, and so on) to
connect the CE routers to the PE routers and the PE routers to the P routers. The MPLS VPN carrier
supporting carrier feature is link layer independent. The CE routers and PE routers use IP to
communicate, and the backbone carrier uses MPLS.
The customer carrier can use any addressing scheme and still be supported by a backbone carrier. The
customer address space and routing information are independent of the address space and routing
information of other customer carriers or the backbone provider.
Benefits of Implementing MPLS VPN CSC with BGP
You can configure your CSC network to enable BGP to transport routes and MPLS labels between the
backbone carrier PE routers and the customer carrier CE routers using multiple paths. The benefits of using
BGP to distribute IPv4 routes and MPLS label routes are:
•
•
BGP takes the place of an IGP and LDP in a VPN forwarding/routing instance (VRF) table. You can
use BGP to distribute routes and MPLS labels. Using a single protocol instead of two simplifies the
configuration and troubleshooting.
BGP is the preferred routing protocol for connecting two ISPs, mainly because of its routing policies
and ability to scale. ISPs commonly use BGP between two providers. This feature enables those ISPs
to use BGP.
Configuration Options for MPLS VPN CSC with BGP
The following sections explain how the backbone and customer carriers distribute IPv4 routes and MPLS
labels. The backbone carrier offers BGP and MPLS VPN services. The customer carrier can be either of the
following:
•
•
Customer Carrier Is an ISP with an IP Core, page 3
Customer Carrier Is an MPLS Service Provider With or Without VPN Services, page 4
Customer Carrier Is an ISP with an IP Core
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MPLS VPN Carrier Supporting Carrier with BGP
Customer Carrier Is an MPLS Service Provider With or Without VPN Services
The figure below shows a network configuration where the customer carrier is an ISP. The customer carrier
has two sites, each of which is a point of presence (POP). The customer carrier connects these sites using a
VPN service provided by the backbone carrier. The backbone carrier uses MPLS. The ISP sites use IP.
Figure 1
Network Where the Customer Carrier Is an ISP
The links between the CE and PE routers use EBGP to distribute IPv4 routes and MPLS labels. Between
the links, the PE routers use multiprotocol IBGP to distribute VPNv4 routes.
Note
If a router other than a Cisco router is used as a CSC-PE or CSC-CE, that router must support IPv4 BGP
label distribution (RFC 3107). Otherwise, you cannot run EBGP with labels between the routers.
Customer Carrier Is an MPLS Service Provider With or Without VPN Services
The figure below shows a network configuration where the backbone carrier and the customer carrier are
BGP/MPLS VPN service providers. This is known as hierarchical VPNs. The customer carrier has two
sites. Both the backbone carrier and the customer carrier use MPLS in their networks.
Figure 2
Network Where the Customer Carrier Is an MPLS VPN Service Provider
In this configuration, the customer carrier can configure its network in one of the following ways:
•
•
The customer carrier can run IGP and LDP in its core network. In this case, the CSC-CE1 router in the
customer carrier redistributes the EBGP routes it learns from the CSC-PE1 router of the backbone
carrier to IGP.
The CSC-CE1 router of the customer carrier system can run an IPv4 and labels IBGP session with the
PE1 router.
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Identifying the Carrier Supporting Carrier Topology
How to Configure MPLS VPN CSC with BGP
How to Configure MPLS VPN CSC with BGP
•
•
•
•
•
Identifying the Carrier Supporting Carrier Topology, page 5
Configuring the Backbone Carrier Core, page 6
Configuring the CSC-PE and CSC-CE Routers, page 13
Configuring the Customer Carrier Network, page 22
Configuring the Customer Site for Hierarchical VPNs, page 26
Identifying the Carrier Supporting Carrier Topology
Before you configure the MPLS VPN CSC with BGP, you need to identify both the backbone and
customer carrier topology.
For hierarchical VPNs, the customer carrier of the MPLS VPN network provides MPLS VPN services to its
own customers. In this instance, you need to identify the type of customer carrier as well as the topology of
the customer carriers. Hierarchical VPNs require extra configuration steps, which are noted in the
configuration sections.
Note
You can connect multiple CSC-CE routers to the same PE, or you can connect a single CSC-CE router to
CSC-PEs using more than one interface to provide redundancy and multiple path support in CSC topology.
Perform this task to identify the carrier supporting carrier topology.
SUMMARY STEPS
1. Identify the type of customer carrier, ISP or MPLS VPN service provider.
2. (For hierarchical VPNs only) Identify the CE routers.
3. (For hierarchical VPNs only) Identify the customer carrier core router configuration.
4. Identify the customer carrier edge (CSC-CE) routers.
5. Identify the backbone carrier router configuration.
DETAILED STEPS
Command or Action
Purpose
Step 1 Identify the type of customer carrier,
ISP or MPLS VPN service provider.
Sets up requirements for configuration of carrier supporting carrier network.
Step 2 (For hierarchical VPNs only) Identify
the CE routers.
Sets up requirements for configuration of CE to PE connections.
Step 3 (For hierarchical VPNs only) Identify
the customer carrier core router
configuration.
Sets up requirements for connection configuration between core (P) routers and
between P routers and edge routers (PE and CSC-CE routers).
•
•
For an ISP, customer site configuration is not required.
For an MPLS VPN service provider, the customer site needs to be
configured, as well as any task or step designated “for hierarchical VPNs
only.”
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Configuring the Backbone Carrier Core
What to Do Next
Command or Action
Purpose
Step 4 Identify the customer carrier edge
(CSC-CE) routers.
Sets up requirements for configuration of CSC-CE to CSC-PE connections.
Step 5 Identify the backbone carrier router
configuration.
Sets up requirements for connection configuration between CSC core routers
and between CSC core routers and edge routers (CSC-CE and CSC-PE routers).
•
What to Do Next, page 6
What to Do Next
Set up your carrier supporting carrier networks with the Configuring the Backbone Carrier Core, page
6.
Configuring the Backbone Carrier Core
Configuring the backbone carrier core requires setting up connectivity and routing functions for the CSC
core and the CSC-PE routers.
Configuring and verifying the CSC core (backbone carrier) involves the following tasks:
•
•
•
•
Prerequisites, page 6
Verifying IP Connectivity and LDP Configuration in the CSC Core, page 6
Configuring VRFs for CSC-PE Routers, page 9
Configuring Multiprotocol BGP for VPN Connectivity in the Backbone Carrier, page 11
Prerequisites
Before you configure a backbone carrier core, configure the following on the CSC core routers:
•
•
An IGP routing protocol--BGP, OSPF, IS-IS, EIGRP, static, and so on.
Label Distribution Protocol (LDP). For information, see How to Configure MPLS LDP.
Verifying IP Connectivity and LDP Configuration in the CSC Core
Perform this task to verify IP connectivity and LDP configuration in the CSC core.
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Verifying IP Connectivity and LDP Configuration in the CSC Core
SUMMARY STEPS
1. enable
2. ping [protocol] {host-name | system-address}
3. trace [protocol] [destination]
4. show mpls forwarding-table [vrf vrf-name] [{network {mask | length} | labels label [- label] |
interface interface | next-hop address | lsp-tunnel [tunnel-id]}] [detail]
5. show mpls ldp discovery [vrf vrf-name | all]
6. show mpls ldp neighbor [[vrf vrf-name] [address | interface] [detail] | all]
7. show ip cef [vrf vrf-name] [network [mask]] [longer-prefixes] [detail]
8. show mpls interfaces [[vrf vrf-name] [interface] [detail] | all]
9. show ip route
10. disable
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 ping [protocol] {host-name | system-address} (Optional) Diagnoses basic network connectivity on AppleTalk, CLNS,
IP, Novell, Apollo, VINES, DECnet, or XNS networks.
Example:
•
Use the ping ip command to verify the connectivity from one CSC
core router to another.
Router# ping ip 10.1.0.0
Step 3 trace [protocol] [destination]
Example:
Router# trace ip 10.2.0.0
(Optional) Discovers the routes that packets will actually take when
traveling to their destination.
•
Use the trace command to verify the path that a packet goes
through before reaching the final destination. The trace command
can help isolate a trouble spot if two routers cannot communicate.
Step 4 show mpls forwarding-table [vrf vrf-name] (Optional) Displays the contents of the MPLS label forwarding
information base (LFIB).
[{network {mask | length} | labels label [label] | interface interface | next-hop address
• Use the show mpls forwarding-table command to verify that
| lsp-tunnel [tunnel-id]}] [detail]
MPLS packets are being forwarded.
Example:
Router# show mpls forwarding-table
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Troubleshooting Tips
Command or Action
Purpose
Step 5 show mpls ldp discovery [vrf vrf-name | all] (Optional) Displays the status of the LDP discovery process.
•
Example:
Use the show mpls ldp discovery command to verify that LDP is
operational in the CSC core.
Router# show mpls ldp discovery
Step 6 show mpls ldp neighbor [[vrf vrf-name]
[address | interface] [detail] | all]
(Optional) Displays the status of LDP sessions.
•
Use the show mpls ldp neighbor command to verify LDP
configuration in the CSC core.
Example:
Router# show mpls ldp neighbor
Step 7 show ip cef [vrf vrf-name] [network [mask]]
[longer-prefixes] [detail]
(Optional) Displays entries in the forwarding information base (FIB).
•
Use the show ip cef command to check the forwarding table
(prefixes, next hops, and interfaces).
Example:
Router# show ip cef
Step 8 show mpls interfaces [[vrf vrf-name]
[interface] [detail] | all]
(Optional) Displays information about one or more or all interfaces that
are configured for label switching.
•
Example:
Use the show mpls interfaces command to verify that the interfaces
are configured to use LDP.
Router# show mpls interfaces
Step 9 show ip route
(Optional) Displays IP routing table entries.
•
Example:
Use the show ip route command to display the entire routing table,
including host IP address, next hop, interface, and so forth.
Router# show ip route
Step 10 disable
(Optional) Returns to privileged EXEC mode.
Example:
Router# disable
•
Troubleshooting Tips, page 8
Troubleshooting Tips
You can use the ping and trace commands to verify complete MPLS connectivity in the core. You also get
useful troubleshooting information from the additional show commands.
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Configuring VRFs for CSC-PE Routers
Configuring VRFs for CSC-PE Routers
Perform this task to configure VPN forwarding/routing instances (VRFs) for the backbone carrier edge
(CSC-PE) routers.
SUMMARY STEPS
1. enable
2. configure terminal
3. ip vrf vrf-name
4. rd route-distinguisher
5. route-target {import | export | both} route-target-ext-community
6. import map route-map
7. exit
8. interface type number
9. ip vrf forwarding vrf-name
10. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 ip vrf vrf-name
Example:
Defines the VPN routing instance by assigning a VRF name and enters VRF
configuration mode.
•
The vrf-name argument is the name assigned to a VRF.
Router(config)# ip vrf vpn1
Step 4 rd route-distinguisher
Creates routing and forwarding tables.
•
Example:
Router(config-vrf)# rd 100:1
The route-distinguisher argument adds an 8-byte value to an IPv4 prefix
to create a VPN IPv4 prefix. You can enter an RD in either of these
formats:
◦
◦
16-bit AS number: your 32-bit number, for example, 101:3
32-bit IP address: your 16-bit number, for example, 192.168.122.15:1
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Command or Action
Step 5 route-target {import | export | both}
route-target-ext-community
Purpose
Creates a route-target extended community for a VRF.
•
Example:
•
Router(config-vrf)# route-target
import 100:1
•
•
Step 6 import map route-map
The import keyword imports routing information from the target VPN
extended community.
The export keyword exports routing information to the target VPN
extended community.
The both keyword imports routing information from and exports routing
information to the target VPN extended community.
The route-target-ext-community argument adds the route-target extended
community attributes to the VRF's list of import, export, or both (import
and export) route-target extended communities.
(Optional) Configures an import route map for a VRF.
•
Example:
The route-map argument specifies the route map to be used as an import
route map for the VRF.
Router(config-vrf)# import map
vpn1-route-map
Step 7 exit
(Optional) Exits to global configuration mode.
Example:
Router(config-vrf)# exit
Step 8 interface type number
Specifies the interface to configure.
•
•
Example:
The type argument specifies the type of interface to be configured.
The number argument specifies the port, connector, or interface card
number.
Router(config)# interface
Ethernet5/0
Step 9 ip vrf forwarding vrf-name
Associates a VRF with the specified interface or subinterface.
•
The vrf-name argument is the name assigned to a VRF.
Example:
Router(config-if)# ip vrf
forwarding vpn1
Step 10 end
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-if)# end
•
Troubleshooting Tips, page 11
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Troubleshooting Tips
Troubleshooting Tips
Enter a show ip vrf detail command and make sure the MPLS VPN is up and associated with the right
interfaces.
Configuring Multiprotocol BGP for VPN Connectivity in the Backbone Carrier
Perform this task to configure Multiprotocol BGP (MP-BGP) connectivity in the backbone carrier.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. no bgp default ipv4-unicast
5. neighbor {ip-address | peer-group-name} remote-as as-number
6. neighbor {ip-address | peer-group-name} update-source interface-type
7. address-family vpnv4 [unicast]
8. neighbor {ip-address | peer-group-name} send-community extended
9. neighbor {ip-address | peer-group-name} activate
10. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Configures a BGP routing process and enters router configuration mode.
•
Example:
Router(config)# router bgp 100
The as-number argument indicates the number of an autonomous
system that identifies the router to other BGP routers and tags the
routing information passed along. Valid numbers are from 0 to
65535. Private autonomous system numbers that can be used in
internal networks range from 64512 to 65535.
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Configuring Multiprotocol BGP for VPN Connectivity in the Backbone Carrier
Command or Action
Step 4 no bgp default ipv4-unicast
Purpose
(Optional) Disables the IPv4 unicast address family on all neighbors.
•
Example:
Use the no bgp default-unicast command if you are using this
neighbor for MPLS routes only.
Router(config-router)# no bgp
default ipv4-unicast
Step 5 neighbor {ip-address | peer-group-name}
remote-as as-number
Example:
Adds an entry to the BGP or multiprotocol BGP neighbor table.
•
•
•
Router(config-router)# neighbor
10.5.5.5 remote-as 100
Step 6 neighbor {ip-address | peer-group-name}
update-source interface-type
Allows BGP sessions to use a specific operational interface for TCP
connections.
•
Example:
Router(config-router)# neighbor
10.2.0.0 update-source loopback0
Step 7 address-family vpnv4 [unicast]
Example:
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
The as-number argument specifies the autonomous system to which
the neighbor belongs.
•
•
The ip-address argument specifies the IP address of the BGPspeaking neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
The interface-type argument specifies the interface to be used as the
source.
Enters address family configuration mode for configuring routing
sessions, such as BGP, that use standard VPNv4 address prefixes.
•
The optional unicast keyword specifies VPNv4 unicast address
prefixes.
Router(config-router)# addressfamily vpnv4
Step 8 neighbor {ip-address | peer-group-name}
send-community extended
Example:
Specifies that a communities attribute should be sent to a BGP neighbor.
•
•
The ip-address argument specifies the IP address of the BGPspeaking neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
Router(config-router-af)# neighbor
10.0.0.1 send-community extended
Step 9 neighbor {ip-address | peer-group-name}
activate
Example:
Enables the exchange of information with a neighboring BGP router.
•
•
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
Router(config-router-af)# neighbor
10.4.0.0 activate
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Configuring the CSC-PE and CSC-CE Routers
Troubleshooting Tips
Command or Action
Purpose
Step 10 end
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-router-af)# end
•
•
Troubleshooting Tips, page 13
Troubleshooting Tips, page 68
Troubleshooting Tips
You can enter a show ip bgp neighbor command to verify that the neighbors are up and running. If this
command is not successful, enter a debug ip bgp x.x.x.x events command, where x.x.x.x is the IP address
of the neighbor.
Configuring the CSC-PE and CSC-CE Routers
Perform the following tasks to configure and verify links between a CSC-PE router and the carrier CSC-CE
router for an MPLS VPN CSC network that uses BGP to distribute routes and MPLS labels.
The figure below shows the configuration for the peering with directly connected interfaces between CSCPE and CSC-CE routers. This configuration is used as the example in the tasks that follow.
Figure 3
•
•
•
•
Configuration for Peering with Directly Connected Interfaces Between CSC-PE and CSC-CE Routers
Configuring CSC-PE Routers, page 13
Configuring CSC-CE Routers, page 16
Verifying Labels in the CSC-PE Routers, page 18
Verifying Labels in the CSC-CE Routers, page 20
Configuring CSC-PE Routers
Perform this task to configure the CSC-PE routers.
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Configuring CSC-PE Routers
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. address-family ipv4 [ multicast | unicast | vrf vrf-name ]
5. neighbor {ip-address | peer-group-name} remote-as as-number
6. neighbor {ip-address | peer-group-name} activate
7. neighbor ip-address as-override
8. neighbor ip-address send-label
9. exit-address-family
10. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Configures a BGP routing process and enters router configuration mode.
•
Example:
Router(config)# router bgp 100
Step 4 address-family ipv4 [ multicast | unicast |
vrf vrf-name ]
Example:
Router(config-router)# addressfamily ipv4 vrf vpn1
The as-number argument indicates the number of an autonomous
system that identifies the router to other BGP routers and tags the
routing information passed along. Valid numbers are from 0 to
65535. Private autonomous system numbers that can be used in
internal networks range from 64512 to 65535.
Specifies the IPv4 address family type and enters address family
configuration mode.
•
•
•
The multicast keyword specifies IPv4 multicast address prefixes.
The unicast keyword specifies IPv4 unicast address prefixes.
The vrf vrf-name keyword and argument specify the name of the
VRF to associate with subsequent IPv4 address family configuration
mode commands.
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Troubleshooting Tips
Command or Action
Purpose
Step 5 neighbor {ip-address | peer-group-name}
remote-as as-number
Example:
Adds an entry to the BGP or multiprotocol BGP neighbor table.
•
•
•
Router(config-router-af)# neighbor
10.0.0.1 remote-as 200
Step 6 neighbor {ip-address | peer-group-name}
activate
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
The as-number argument specifies the autonomous system to which
the neighbor belongs.
Enables the exchange of information with a neighboring BGP router.
•
•
Example:
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
Router(config-router-af)# neighbor
10.0.0.2 activate
Step 7 neighbor ip-address as-override
Configures a PE router to override the autonomous system number (ASN)
of a site with the ASN of a provider.
•
Example:
The ip-address argument specifies the IP address of the router that is
to be overridden with the ASN provided.
Router(config-router-af)# neighbor
10.0.0.2 as-override
Step 8 neighbor ip-address send-label
Enables a BGP router to send MPLS labels with BGP routes to a
neighboring BGP router.
•
Example:
The ip-address argument specifies the IP address of the neighboring
router.
Router(config-router-af)# neighbor
10.0.0.2 send-label
Step 9 exit-address-family
Exits address family configuration mode.
Example:
Router(config-router-af)# exitaddress-family
Step 10 end
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-router)# end
•
Troubleshooting Tips, page 15
Troubleshooting Tips
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Configuring CSC-CE Routers
Enter a show ip bgp neighbor command to verify that the neighbors are up and running. Make sure you
see the following line in the command output under Neighbor capabilities:
IPv4 MPLS Label capability:advertised and received
Configuring CSC-CE Routers
Perform this task to configure the CSC-CE routers.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. address-family ipv4 [multicast | unicast | vrf vrf-name]
5. redistribute protocol
6. neighbor {ip-address | peer-group-name} remote-as as-number
7. neighbor {ip-address | peer-group-name} activate
8. neighbor ip-address send-label
9. exit-address-family
10. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Configures a BGP routing process and enters router configuration mode.
•
Example:
Router(config)# router bgp 200
The as-number argument indicates the number of an autonomous system
that identifies the router to other BGP routers and tags the routing
information passed along. Valid numbers are from 0 to 65535. Private
autonomous system numbers that can be used in internal networks range
from 64512 to 65535.
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Command or Action
Step 4 address-family ipv4 [multicast |
unicast | vrf vrf-name]
Example:
Purpose
Specifies the IPv4 address family type and enters address family configuration
mode.
•
•
•
Router(config-router)# addressfamily ipv4
Step 5 redistribute protocol
The multicast keyword specifies IPv4 multicast address prefixes.
The unicast keyword specifies IPv4 unicast address prefixes.
The vrf vrf-name keyword and argument specify the name of the VRF to
associate with subsequent IPv4 address family configuration mode
commands.
Redistributes routes from one routing domain into another routing domain.
•
Example:
Router(config-router-af)#
redistribute static
The protocol argument specifies the source protocol from which routes are
being redistributed. It can be one of the following keywords: bgp, egp,
igrp, isis, ospf, mobile, static [ip], connected, and rip.
◦
◦
Step 6 neighbor {ip-address | peer-groupname} remote-as as-number
Example:
The static [ip] keyword redistributes IP static routes. The optional ip
keyword is used when you redistribute static routes into IS-IS.
The connected keyword refers to routes which are established
automatically when IP is enabled on an interface. For routing
protocols such as OSPF and IS-IS, these routes are redistributed as
external to the autonomous system.
Adds an entry to the BGP or multiprotocol BGP neighbor table.
•
•
•
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer group.
The as-number argument specifies the autonomous system to which the
neighbor belongs.
Router(config-router-af)#
neighbor 10.5.0.2 remote-as 100
Step 7 neighbor {ip-address | peer-groupname} activate
Enables the exchange of information with a neighboring BGP router.
•
•
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer group.
Example:
Router(config-router-af)#
neighbor 10.3.0.2 activate
Step 8 neighbor ip-address send-label
Example:
Enables a BGP router to send MPLS labels with BGP routes to a neighboring
BGP router.
•
The ip-address argument specifies the IP address of the neighboring router.
Router(config-router-af)#
neighbor 10.0.0.2 send-label
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Verifying Labels in the CSC-PE Routers
Command or Action
Purpose
Step 9 exit-address-family
Exits from the address family configuration mode.
Example:
Router(config-router-af)# exitaddress-family
Step 10 end
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-router)# end
Verifying Labels in the CSC-PE Routers
Perform this task to verify the labels in the CSC-PE routers.
SUMMARY STEPS
1. enable
2. show ip bgp vpnv4 {all | rd route-distinguisher | vrf vrf-name} [summary] [labels]
3. show mpls interfaces [all]
4. show ip route vrf vrf-name [prefix]
5. show ip bgp vpnv4 {all | rd route-distinguisher | vrf vrf-name} [summary] [labels]
6. show ip cef [vrf vrf-name] [network [mask]] [longer-prefixes] [detail]
7. show mpls forwarding-table [vrf vrf-name] [{network {mask | length} | labels label [label] | interface
interface | next-hop address | lsp-tunnel [tunnel-id]}] [detail]
8. traceroute vrf [vrf-name] ip-address
9. disable
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
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Verifying Labels in the CSC-PE Routers
Command or Action
Step 2 show ip bgp vpnv4 {all | rd routedistinguisher | vrf vrf-name}
[summary] [labels]
Purpose
(Optional) Displays VPN address information from the BGP table.
•
Example:
Use the show ip bgp vpnv4 all summary command to check that the BGP
session is up and running between the CSC-PE routers and the CSC-CE
routers. Check the data in the State/PfxRcd column to verify that prefixes are
learned during each session.
Router# show ip bgp vpnv4 all
summary
Step 3 show mpls interfaces [all]
Example:
(Optional) Displays information about one or more interfaces that have been
configured for label switching.
•
Router# show mpls interfaces
all
Step 4 show ip route vrf vrf-name [prefix]
(Optional) Displays the IP routing table associated with a VRF.
•
Example:
Router# show ip route vrf vpn1
10.5.5.5
Step 5 show ip bgp vpnv4 {all | rd routedistinguisher | vrf vrf-name}
[summary] [labels]
Example:
Use the show mpls interfaces all command to check that MPLS interfaces are
up and running, and that LDP-enabled interfaces show that LDP is up and
running. Check that LDP is turned off on the VRF because EBGP distributes
the labels.
Use the show ip route vrf command to check that the prefixes for the PE
routers are in the routing table of the CSC-PE routers.
Note If you have multiple paths configured between CSC-PE and CSC-CE, verify
that the multiple routes for the same destination learned from the CSC-CE
are installed in the corresponding VRF routing table.
(Optional) Displays VPN address information from the BGP table.
•
Use the show ip bgp vpnv4 vrf vrf-name labels command to check that the
prefixes for the customer carrier MPLS service provider networks are in the
BGP table and have the appropriate labels.
Note If you have multiple paths configured between CSC-PE and CSC-CE, verify
that the labels for the same destination learned from the CSC-CE are
installed in the corresponding VRF routing table.
Router# show ip bgp vpnv4 vrf
vpn1 labels
Step 6 show ip cef [vrf vrf-name] [network (Optional) Displays entries in the forwarding information base (FIB) or displays a
summary of the FIB.
[mask]] [longer-prefixes] [detail]
•
Example:
Use the show ip cef vrf and the show ip cef vrf detail commands to check
that the prefixes of the PE routers are in the CEF table.
Router# show ip cef vrf vpn1
10.1.0.0 detail
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Verifying Labels in the CSC-CE Routers
Command or Action
Purpose
Step 7 show mpls forwarding-table [vrf
(Optional) Displays the contents of the MPLS lable forwarding information base
vrf-name] [{network {mask | length} (LFIB).
| labels label [label] | interface
• Use the show mpls forwarding-table command with the vrf keyword and
interface | next-hop address | lspboth the vrf and detail keywords to check that the prefixes for the PE routers
tunnel [tunnel-id]}] [detail]
in the local customer MPLS VPN service provider are in the LFIB.
Note If you have multiple paths configured between CSC-PE and CSC-CE, verify
Example:
that the labels for the same destination learned from the CSC-CE are
installed in the corresponding VRF table.
Router# show mpls forwardingtable vrf vpn1 10.1.0.0 detail
Step 8 traceroute vrf [vrf-name] ipaddress
Shows the routes that packets follow traveling through a network to their
destination.
•
Example:
Router# traceroute vrf vpn2
10.2.0.0
Use the traceroute vrf command to check the data path and transport labels
from a PE to a destination CE router.
Note This command works with MPLS-aware traceroute only if the backbone
routers are configured to propagate and generate IP Time to Live (TTL)
information. For more information, see the documentation on the mpls ip
propagate-ttl command.
Note If you have multiple paths configured between CSC-PE and CSC-CE, verify
that the multiple routes for the same destination learned from the CSC-CE
are installed in the corresponding VRF table.
Step 9 disable
(Optional) Exits to user EXEC mode.
Example:
Router# disable
Verifying Labels in the CSC-CE Routers
Perform this task to verify the labels in the CSC-CE routers.
SUMMARY STEPS
1. enable
2. show ip bgp summary
3. show ip route [address]
4. show mpls ldp bindings [network {mask | length}]
5. show ip cef [network [mask]] [longer-prefixes] [detail]
6. show mpls forwarding table [vrf vrf-name] [{network {mask | length} | labels label [- label] |
interface interface | next-hop address | lsp-tunnel [tunnel-id]}] [detail]
7. show ip bgp labels
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Verifying Labels in the CSC-CE Routers
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 show ip bgp summary
(Optional) Displays the status of all BGP connections.
•
Example:
Use the show ip bgp summary command to check that the BGP session
is up and running on the CSC-CE routers.
Router# show ip bgp summary
Step 3 show ip route [address]
(Optional) Displays IP routing table entries.
•
Example:
Router# show ip route 10.1.0.0
Use the show ip route to check that the loopback address of the local and
remote PE routers are in the routing table.
Note If you have multiple paths configured between CSC-PE and CSC-CE,
verify that the multiple routes for the same destination learned from the
CSC-CE are installed in the corresponding VRF table.
Step 4 show mpls ldp bindings [network {mask (Optional) Displays the contents of the label information base (LIB).
| length}]
• Use the show mpls ldp bindings command to check that the prefix of the
local PE router is in the MPLS LDP bindings.
Example:
Router# show mpls ldp bindings
10.2.0.0 255.255.255.255
Step 5 show ip cef [network [mask]] [longerprefixes] [detail]
(Optional) Displays entries in the forwarding information base (FIB) or a
summary of the FIB.
•
Example:
Router# show ip cef 10.5.0.0
detail
Use the show ip cef and the show ip cef detail commands to check that
the prefixes of the local and remote PE routers are in the Cisco Express
Forwarding table.
Note If you have multiple paths configured between CSC-PE and CSC-CE,
verify that the multiple routes and the labels for the same destination
learned from the CSC-CE are installed in the corresponding VRF table.
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Configuring the Customer Carrier Network
Prerequisites
Command or Action
Purpose
Step 6 show mpls forwarding table [vrf vrf(Optional) Displays the contents of the MPLS LFIB.
name] [{network {mask | length} | labels
• Use the show mpls forwarding-table and show mpls forwarding-table
label [- label] | interface interface | nextdetail commands to check that the prefixes of the local and remote PE
hop address | lsp-tunnel [tunnel-id]}]
routers are in the MPLS forwarding table.
[detail]
Note If you have multiple paths configured between CSC-PE and CSC-CE,
verify that the multiple routes and labels for the same destination
Example:
learned from the CSC-CE are installed in the corresponding VRF
routing table.
Router# show mpls forwardingtable 10.2.0.0 detail
Step 7 show ip bgp labels
(Optional) Displays information about MPLS labels from the EBGP route
table.
•
Example:
Router# show ip bgp labels
Use the show ip bgp labels command to check that the BGP routing table
contains labels for prefixes in the customer carrier MPLS VPN service
provider networks.
Configuring the Customer Carrier Network
Perform the following tasks to configure and verify the customer carrier network. This requires setting up
connectivity and routing functions for the customer carrier core (P) routers and the customer carrier edge
(PE) routers.
•
•
•
•
Prerequisites, page 22
Verifying IP Connectivity in the Customer Carrier, page 22
Configuring a Customer Carrier Core Router as a Route Reflector, page 23
Troubleshooting Tips, page 25
Prerequisites
Before you configure an MPLS VPN CSC network that uses BGP to distribute routes and MPLS labels,
you must configure the following on your customer carrier routers:
•
•
•
Note
An IGP routing protocol--BGP, OSPF, IS-IS, EIGRP, static, and so on. For information, see
Configuring a Basic BGP Network, Configuring OSPF, Configuring a Basic IS-IS Network, and
Configuring EIGRP.
MPLS VPN functionality on the PE routers (for hierarchical VPNs only).
Label Distribution Protocol (LDP) on P and PE routers (for hierarchical VPNs only). For information,
see How to Configure MPLS LDP.
You must configure the items in the preceding list before performing the tasks in this section.
Verifying IP Connectivity in the Customer Carrier
Perform this task to verify IP connectivity in the customer carrier.
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Configuring a Customer Carrier Core Router as a Route Reflector
SUMMARY STEPS
1. enable
2. ping [protocol] {host-name | system-address}
3. trace [protocol] [destination]
4. show ip route
5. disable
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 ping [protocol] {host-name | systemaddress}
Diagnoses basic network connectivity on AppleTalk, CLNS, IP, Novell, Apollo,
VINES, DECnet, or XNS networks.
•
Example:
Use the ping command to verify the connectivity from one customer carrier
core router to another.
Router# ping ip 10.2.0.0
Step 3 trace [protocol] [destination]
Discovers the routes that packets will actually take when traveling to their
destination.
•
Example:
Router# trace ip 10.1.0.0
Step 4 show ip route
Use the trace command to verify the path that a packet goes through before
reaching the final destination. The trace command can help isolate a trouble
spot if two routers cannot communicate.
Displays IP routing table entries.
•
Example:
Use the show ip route command to display the entire routing table,
including host IP address, next hop, interface, and so forth.
Router# show ip route
Step 5 disable
Returns to user mode.
Example:
Router# disable
Configuring a Customer Carrier Core Router as a Route Reflector
Perform this task to configure a customer carrier core (P) router as a route reflector of multiprotocol BGP
prefixes.
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Configuring a Customer Carrier Core Router as a Route Reflector
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. neighbor {ip-address | peer-group-name} remote-as as-number
5. address-family vpnv4 [unicast]
6. neighbor {ip-address | peer-group-name} activate
7. neighbor ip-address route-reflector-client
8. exit-address-family
9. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Configures a BGP routing process and enters router configuration mode.
•
Example:
Router(config)# router bgp 200
Step 4 neighbor {ip-address | peer-group-name}
remote-as as-number
Example:
Router(config-router)# neighbor
10.1.1.1 remote-as 100
The as-number argument indicates the number of an autonomous
system that identifies the router to other BGP routers and labels the
routing information passed along. Valid numbers are from 0 to
65535. Private autonomous system numbers that can be used in
internal networks range from 64512 to 65535.
Adds an entry to the BGP or multiprotocol BGP neighbor table.
•
•
•
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
The as-number argument specifies the autonomous system to which
the neighbor belongs.
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Troubleshooting Tips
Command or Action
Purpose
Step 5 address-family vpnv4 [unicast]
Enters address family configuration mode for configuring routing
sessions, such as BGP, that use standard VPNv4 address prefixes.
•
Example:
The optional unicast keyword specifies VPNv4 unicast address
prefixes.
Router(config-router)# address-family
vpnv4
Step 6 neighbor {ip-address | peer-group-name}
activate
Enables the exchange of information with a neighboring BGP router.
•
•
Example:
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
Router(config-router-af)# neighbor
10.1.1.1 activate
Step 7 neighbor ip-address route-reflector-client
Configures the router as a BGP route reflector and configures the
specified neighbor as its client.
•
Example:
The ip-address argument specifies the IP address of the BGP
neighbor being identified as a client.
Router(config-router-af)# neighbor
10.1.1.1 route-reflector-client
Step 8 exit-address-family
Exits address family configuration mode.
Example:
Router(config-router-af)# exit-addressfamily
Step 9 end
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-router)# end
Troubleshooting Tips
By default, neighbors that are defined using the neighbor remote-as command in router configuration
mode exchange only unicast address prefixes. For neighbors to exchange other address prefix types, such as
multicast and VPNv4, you must also activate neighbors using the neighbor activate command in address
family configuration mode, as shown.
Route reflectors and clients (neighbors or internal BGP peer groups) that are defined in router configuration
mode using the neighbor route-reflector-client command reflect unicast address prefixes to and from
those clients by default. To cause them to reflect prefixes for other address families, such as multicast,
define the reflectors and clients in address family configuration mode, using the neighbor route-reflectorclient command, as shown.
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Configuring the Customer Site for Hierarchical VPNs
Defining VPNs on PE Routers for Hierarchical VPNs
Configuring the Customer Site for Hierarchical VPNs
Note
This section applies only to customer carrier networks that use BGP to distribute routes and MPLS labels.
Perform the following tasks to configure and verify the customer site for hierarchical VPNs:
Note
This section applies to hierarchical VPNs only.
•
•
•
•
•
Defining VPNs on PE Routers for Hierarchical VPNs, page 26
Configuring BGP Routing Sessions on the PE Routers for Hierarchical VPNs, page 28
Verifying Labels in Each PE Router for Hierarchical VPNs, page 29
Configuring CE Routers for Hierarchical VPNs, page 30
Verifying IP Connectivity in the Customer Site, page 32
Defining VPNs on PE Routers for Hierarchical VPNs
Perform this task to define VPNs on PE routers.
SUMMARY STEPS
1. enable
2. configure terminal
3. ip vrf vrf-name
4. rd route-distinguisher
5. route-target {import | export | both} route-target-ext-community
6. import map route-map
7. ip vrf forwarding vrf-name
8. exit
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
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Command or Action
Purpose
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 ip vrf vrf-name
Creates a VRF routing table and a Cisco Express Forwarding table and
enters VRF configuration mode.
•
Example:
The vrf-name argument is a name you assign to a VRF.
Router(config)# ip vrf vpn2
Step 4 rd route-distinguisher
Creates routing and forwarding tables for a VRF.
•
Example:
The route-distinguisher argument adds an 8-byte value to an IPv4
prefix to create a VPN IPv4 prefix.
Router(config-vrf)# rd 200:1
Step 5 route-target {import | export | both}
route-target-ext-community
Creates a route-target extended community for a VRF.
•
Example:
•
Router(config-vrf)# route-target
export 200:1
•
•
Step 6 import map route-map
The import keyword imports routing information from the target VPN
extended community.
The export keyword exports routing information to the target VPN
extended community.
The both keyword imports routing information from and export
routing information to the target VPN extended community.
The route-target-ext-community argument adds the route-target
extended community attributes to the VRF's list of import, export, or
both (import and export) route-target extended communities.
Configures an import route map for a VRF.
•
Example:
The route-map argument specifies the route map to be used as an
import route map for the VRF.
Router(config-vrf)# import map map23
Step 7 ip vrf forwarding vrf-name
Associates a VPN VRF instance with an interface or subinterface.
•
The vrf-name argument is the name assigned to a VRF.
Example:
Router(config-vrf)# ip vrf
forwarding vpn2
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Configuring BGP Routing Sessions on the PE Routers for Hierarchical VPNs
Command or Action
Step 8 exit
Purpose
Exits to global configuration mode.
Example:
Router(config-vrf)# exit
Configuring BGP Routing Sessions on the PE Routers for Hierarchical VPNs
Perform this task to configure BGP routing sessions on the PE routers for PE-to-CE router communication.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. address-family ipv4 [multicast | unicast | vrf vrf-name]
5. neighbor {ip-address | peer-group-name} remote-as as-number
6. neighbor {ip-address | peer-group-name} activate
7. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Example:
Router(config)# router bgp 200
Configures the router to run a BGP process and enters router configuration
mode.
•
The as-number argument indicates the number of an autonomous
system that identifies the router to other BGP routers and tags the
routing information passed along. Valid numbers are from 0 to 65535.
Private autonomous system numbers that can be used in internal
networks range from 64512 to 65535.
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Verifying Labels in Each PE Router for Hierarchical VPNs
Command or Action
Purpose
Step 4 address-family ipv4 [multicast | unicast |
vrf vrf-name]
Specifies the IPv4 address family type and enters address family
configuration mode.
•
•
•
Example:
Router(config-router)# addressfamily ipv4 multicast
Step 5 neighbor {ip-address | peer-group-name}
remote-as as-number
Example:
Adds an entry to the BGP or multiprotocol BGP neighbor table.
•
•
•
Router(config-router-af)# neighbor
10.5.5.5 remote-as 300
Step 6 neighbor {ip-address | peer-group-name}
activate
Example:
The multicast keyword specifies IPv4 multicast address prefixes.
The unicast keyword specifies IPv4 unicast address prefixes.
The vrf vrf-name keyword and argument specify the name of the VRF
to associate with subsequent IPv4 address family configuration mode
commands.
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
The as-number argument specifies the autonomous system to which the
neighbor belongs.
Enables the exchange of information with a neighboring router.
•
•
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
Router(config-router-af)# neighbor
10.1.0.0 activate
Step 7 end
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-router-af)# end
Verifying Labels in Each PE Router for Hierarchical VPNs
Perform this task to verify labels in each PE router for hierarchical VPNs.
SUMMARY STEPS
1. enable
2. show ip route vrf vrf-name [prefix]
3. show mpls forwarding-table [vrf vrf-name] [prefix] [detail]
4. show ip cef [network [mask [longer-prefix]]] [detail]
5. show ip cef vrf vrf-name [ip-prefix]
6. exit
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Configuring CE Routers for Hierarchical VPNs
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 show ip route vrf vrf-name [prefix]
(Optional) Displays the IP routing table associated with a VRF.
•
Example:
Use the show ip route vrf command to check that the loopback
addresses of the local and remote CE routers are in the routing table of
the PE routers.
Router# show ip route vrf vpn2
10.5.5.5
Step 3 show mpls forwarding-table [vrf vrfname] [prefix] [detail]
(Optional) Displays the contents of the LFIB.
•
Example:
Use the show mpls forwarding-table command to check that the
prefixes for the local and remote CE routers are in the MPLS forwarding
table, and that the specified prefix is untagged.
Router# show mpls forwarding-table
vrf vpn2 10.1.0.0
Step 4 show ip cef [network [mask [longerprefix]]] [detail]
(Optional) Displays specific entries in the FIB based on IP address
information.
•
Example:
Use the show ip cef command to check that the prefixes of the local and
remote PE routers are in the Cisco Express Forwarding table.
Router# show ip cef 10.2.0.0
Step 5 show ip cef vrf vrf-name [ip-prefix]
(Optional) Displays the Cisco Express Forwarding table associated with a
VRF.
•
Example:
Use the show ip cef vrf command to check that the prefix of the remote
CE router is in the Cisco Express Forwarding table.
Router# show ip cef vrf vpn2
10.3.0.0
Step 6 exit
(Optional) Exits to user EXEC mode.
Example:
Router# exit
Configuring CE Routers for Hierarchical VPNs
Perform this task to configure CE routers for hierarchical VPNs. This configuration is the same as that for
an MPLS VPN that is not in a hierarchical topology.
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SUMMARY STEPS
1. enable
2. configure terminal
3. ip cef [distributed]
4. interface type number
5. ip addres ip-address mask [secondary]
6. exit
7. router bgp as-number
8. redistribute protocol
9. neighbor {ip-address | peer-group-name} remote-as as-number
10. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 ip cef [distributed]
Enables Cisco Express Forwarding on the route processor card.
•
Example:
Router(config)# ip cef
distributed
The distributed keyword enables distributed Cisco Express Forwarding
operation. Cisco Express Forwarding information is distributed to the line
cards. Line cards perform express forwarding.
Note For the Cisco ASR 1000 Series Aggregation Services Router, the
distributed keyword is required.
Step 4 interface type number
Configures an interface type and enters interface configuration mode.
•
Example:
The type argument specifies the type of interface to be configured.
◦
Router(config)# interface
loopback 0
•
A loopback interface indicates a software-only interface that emulates an
interface that is always up. It is a virtual interface supported on all
platforms.
The number argument is the number of the loopback interface that you want to
create or configure. There is no limit on the number of loopback interfaces
you can create.
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Verifying IP Connectivity in the Customer Site
Command or Action
Step 5 ip addres ip-address mask
[secondary]
Example:
Purpose
Sets a primary or secondary IP address for an interface.
•
•
•
Router(config-if)# ip address
10.8.0.0 255.255.255.255
Step 6 exit
The ip-address argument is the IP address.
The mask argument is the mask for the associated IP subnet.
The secondary keyword specifies that the configured address is a secondary
IP address. If this keyword is omitted, the configured address is the primary IP
address.
Exits interface configuration mode.
Example:
Router(config-if)# exit
Step 7 router bgp as-number
Configures a BGP routing process and enters router configuration mode.
•
Example:
Router(config)# router bgp 100
Step 8 redistribute protocol
Redistributes routes from one routing domain into another routing domain.
•
Example:
Router(config-router)#
redistribute connected
The as-number argument indicates the number of an autonomous system that
identifies the router to other BGP routers and tags the routing information
passed along. Valid numbers are from 0 to 65535. Private autonomous system
numbers that can be used in internal networks range from 64512 to 65535.
The protocol argument specifies the source protocol from which routes are
being redistributed. It can be one of the following keywords: bgp, connected,
egp, igrp, isis, mobile, ospf, static [ip], or rip.
The connected keyword refers to routes that are established automatically when IP
is enabled on an interface. For routing protocols such as Open Shortest Path First
(OSPF) and IS-IS, these routes are redistributed as external to the autonomous
system.
Step 9 neighbor {ip-address | peer-group- Adds the IP address of the neighbor in the remote autonomous system to the
multiprotocol BGP neighbor table of the local router.
name} remote-as as-number
Example:
Router(config-router)#
neighbor 10.8.0.0 remote-as
100
Step 10 end
•
•
•
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer group.
The as-number argument specifies the autonomous system to which the
neighbor belongs.
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-router)# end
Verifying IP Connectivity in the Customer Site
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Verifying IP Connectivity in the Customer Site
Perform this task to verify IP connectivity in the customer site.
SUMMARY STEPS
1. enable
2. show ip route [ip-address [mask]] [longer-prefixes] | protocol [process-id] | list [access-list-number |
access-list-name ] | static download
3. ping [protocol] {host-name | system-address}
4. trace [protocol] [destination]
5. disable
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 show ip route [ip-address [mask]]
(Optional) Displays the current state of the routing table.
[longer-prefixes] | protocol [process-id] |
• Use the show ip route ip-address command to check that the loopback
list [access-list-number | access-listaddresses of the remote CE routers learned through the PE router are in
name ] | static download
the routing table of the local CE routers.
Example:
Router# show ip route 10.5.5.5
Step 3 ping [protocol] {host-name | systemaddress}
Example:
Diagnoses basic network connectivity on Apollo, AppleTalk, Connectionless
Network Service (CLNS), DECnet, IP, Novell IPX, VINES, or XNS
networks.
•
Use the ping command to check connectivity between customer site
routers.
Router# ping 10.5.5.5
Step 4 trace [protocol] [destination]
Discovers the routes that packets will actually take when traveling to their
destination.
Example:
•
Router# trace ip 10.5.5.5
•
Use the trace command to follow the path of the packets in the customer
site.
To use nondefault parameters and invoke an extended trace test, enter the
trace command without a destination argument. You will be stepped
through a dialog to select the desired parameters.
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Configuration Examples for MPLS VPN CSC with BGP
Command or Action
Step 5 disable
Purpose
(Optional) Exits to user EXEC mode.
Example:
Router# disable
Configuration Examples for MPLS VPN CSC with BGP
The figure below shows a sample CSC topology for exchanging IPv4 routes and MPLS labels. Use this
figure as a reference for configuring and verifying carrier supporting carrier routers to exchange IPv4
routes and MPLS labels.
Figure 4
Sample CSC Topology for Exchanging IPv4 Routes and MPLS Labels
The table below describes the sample configuration shown in the figure above.
Table 1
Description of Sample Configuration Shown in figure 1
Routers
Description
CE1 and CE2
Belong to an end customer. CE1 and CE2 routers
exchange routes learned from PE routers.
The end customer is purchasing VPN services from
a customer carrier.
PE1 and PE2
Part of a customer carrier network that is
configured to provide MPLS VPN services. PE1
and PE2 are peering with a VPNv4 IBGP session to
form an MPLS VPN network.
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Configuring the Backbone Carrier Core Examples
Verifying IP Connectivity and LDP Configuration in the CSC Core Example
Routers
Description
CSC-CE1 and CSC-CE2
Part of a customer carrier network. CSC-CE1 and
CSC-CE2 routers exchange IPv4 BGP updates with
MPLS labels and redistribute PE loopback
addressees to and from the IGP (OSPF in this
example).
The customer carrier is purchasing carrier
supporting carrier VPN services from a backbone
carrier.
CSC-PE1 and CSC-PE2
•
•
•
•
Part of the backbone carrier’s network configured
to provide carrier supporting carrier VPN services.
CSC-PE1 and CSC-PE2 are peering with a VPNv4
IP BGP session to form the MPLS VPN network. In
the VRF, CSC-PE1 and CSC-PE2 are peering with
the CSC-CE routers, which are configured for
carrying MPLS labels with the routes, with an IPv4
EBGP session.
Configuring the Backbone Carrier Core Examples, page 35
Configuring the Links Between CSC-PE and CSC-CE Routers Examples, page 37
Configuring the Customer Carrier Network Examples, page 43
Configuring the Customer Site for Hierarchical VPNs Examples, page 44
Configuring the Backbone Carrier Core Examples
Configuration and verification examples for the backbone carrier core included in this section are as
follows:
•
•
•
Verifying IP Connectivity and LDP Configuration in the CSC Core Example, page 35
Configuring VRFs for CSC-PE Routers Example, page 37
Configuring Multiprotocol BGP for VPN Connectivity in the Backbone Carrier Example, page 37
Verifying IP Connectivity and LDP Configuration in the CSC Core Example
Check that CSC-PE2 is reachable from CSC-PE1 by entering the following command on CSC-CE1:
Router# ping 10.5.5.5
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.5.5.5, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/4 ms
Verify the path from CSC-PE1 to CSC-PE2 by entering the following command on CSC-CE1:
Router# trace 10.5.5.5
Type escape sequence to abort.
Tracing the route to 10.5.5.5
1 10.5.5.5 0 msec 0 msec *
Check that CSC-PE router prefixes are in the MPLS forwarding table:
Router# show mpls forwarding-table
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Verifying IP Connectivity and LDP Configuration in the CSC Core Example
Local
tag
16
17
21
22
23
2
8
29
30
Outgoing
tag or VC
2/nn
16
Pop tag
Pop tag
Aggregate
2/nn
2/nn
2/nn
2/nn
Prefix or
Bytes tag
Tunnel Id
switched
dd.dd.dd.dd/32
0
bb.bb.bb.bb/32[V]
30204
cc.cc.cc.cc/32[V]
0
nn.0.0.0/8[V]
570
pp.0.0.0/8[V]
0
gg.gg.gg.gg/32[V]
0
hh.hh.hh.hh/32[V]
15452
qq.0.0.0/8[V]
0
ss.0.0.0/8[V]
0
Outgoing
interface
AT2/1/0.1
Et1/0
Et1/0
Et1/0
Next Hop
AT3/0.1
AT3/0.1
AT3/0.1
AT3/0.1
point2point
point2point
point2point
point2point
point2point
pp.0.0.1
pp.0.0.1
pp.0.0.1
Check the status of LDP discovery processes in the core:
Router# show mpls ldp discovery
Local LDP Identifier:
ee.ee.ee.ee:0
Discovery Sources:
Interfaces:
ATM2/1/0.1 (ldp): xmit/recv
TDP Id: dd.dd.dd.dd:1
Check the status of LDP sessions in the core:
Router# show mpls ldp neighbor
Peer LDP Ident: dd.dd.dd.dd:1; Local LDP Ident ee.ee.ee.ee:1
TCP connection: dd.dd.dd.dd.646 - ee.ee.ee.ee.11007
State: Oper; Msgs sent/rcvd: 20/21; Downstream on demand
Up time: 00:14:56
LDP discovery sources:
ATM2/1/0.1, Src IP addr: dd.dd.dd.dd
Check the forwarding table (prefixes, next-hops, and interfaces):
Router# show ip cef
Prefix
Next Hop
0.0.0.0/0
drop
0.0.0.0/32
receive
dd.dd.dd.dd/32
dd.dd.dd.dd
ee.ee.ee.ee/32
receive
224.0.0.0/4
drop
224.0.0.0/24
receive
255.255.255.255/32 receive
Note
Interface
Null0 (default route handler entry)
ATM2/1/0.1
Also see the Verifying Labels in the CSC-CE Routers Examples, page 41.
Verify that interfaces are configured to use LDP:
Router# show mpls interfaces
Interface
IP
Ethernet0/1
Yes (ldp)
Tunnel
No
Operational
Yes
Display the entire routing table, including host IP address, next hop, interface, and so forth:
Router# show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
Gateway of last resort is not set
dd.0.0.0/32 is subnetted, 1 subnets
O
dd.dd.dd.dd [110/7] via dd.dd.dd.dd, 00:16:42, ATM2/1/0.1
ee.0.0.0/32 is subnetted, 1 subnets
C
ee.ee.ee.ee is directly connected, Loopback0
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Configuring the Links Between CSC-PE and CSC-CE Routers Examples
Configuring VRFs for CSC-PE Routers Example
Configuring VRFs for CSC-PE Routers Example
The following example shows how to configure a VPN routing and forwarding (VRF) instance for a CSCPE router:
ip cef distributed
ip vrf vpn1
rd 100:1
route target both 100:1
!
Configuring Multiprotocol BGP for VPN Connectivity in the Backbone Carrier Example
The following example shows how to configure Multiprotocol BGP (MP-BGP) for VPN connectivity in the
backbone carrier:
ip cef distributed
ip vrf vpn1
rd 100:1
route target both 100:1
hostname csc-pe1
!
router bgp 100
no bgp default ipv4-unicast
bgp log-neighbor-changes
timers bgp 10 30
neighbor ee.ee.ee.ee remote-as 100
neighbor ee.ee.ee.ee update-source Loopback0
no auto-summary
!
address-family vpnv4
neighbor ee.ee.ee.ee activate
neighbor ee.ee.ee.ee send-community extended
bgp dampening 30
exit-address-family
!
router bgp 100
. . .
! (BGP IPv4 to CSC-CE router from CSC-PE router)
!
address-family ipv4 vrf vpn1
neighbor ss.0.0.2 remote-as 200
neighbor ss.0.0.2 activate
neighbor ss.0.0.2 as-override
neighbor ss.0.0.2 advertisement-interval 5
neighbor ss.0.0.2 send-label
no auto-summary
no synchronization
bgp dampening 30
exit-address-family
!
Configuring the Links Between CSC-PE and CSC-CE Routers Examples
This section contains the following examples:
•
•
•
•
Configuring the CSC-PE Routers Examples, page 38
Configuring the CSC-CE Routers Examples, page 38
Verifying Labels in the CSC-PE Routers Examples, page 39
Verifying Labels in the CSC-CE Routers Examples, page 41
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MPLS VPN Carrier Supporting Carrier with BGP
Configuring the CSC-PE Routers Examples
Configuring the CSC-PE Routers Examples
The following example shows how to configure a CSC-PE router:
ip cef
!
ip vrf vpn1
rd 100:1
route-target export 100:1
route-target import 100:1
mpls label protocol ldp
!
interface Loopback0
ip address dd.dd.dd.dd 255.255.255.255
!
interface Ethernet3/1
ip vrf forwarding vpn1
ip address pp.0.0.2 255.0.0.0
!
interface ATM0/1/0
no ip address
no ip directed-broadcast
no ip route-cache distributed
atm clock INTERNAL
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM0/1/0.1 mpls
ip unnumbered Loopback0
no ip directed-broadcast
no atm enable-ilmi-trap
mpls label protocol ldp
mpls atm vpi 2-5
mpls ip
!
router ospf 100
log-adjacency-changes
auto-cost reference-bandwidth 1000
redistribute connected subnets
passive-interface Ethernet3/1
network dd.dd.dd.dd 0.0.0.0 area 100
!
router bgp 100
no bgp default ipv4-unicast
bgp log-neighbor-changes
timers bgp 10 30
neighbor ee.ee.ee.ee remote-as 100
neighbor ee.ee.ee.ee update-source Loopback0
!
address-family vpnv4
neighbor ee.ee.ee.ee activate
neighbor ee.ee.ee.ee send-community extended
bgp dampening 30
exit-address-family
!
address-family ipv4 vrf vpn1
neighbor pp.0.0.1 remote-as 200
neighbor pp.0.0.1 activate
neighbor pp.0.0.1 as-override
neighbor pp.0.0.1 advertisement-interval 5
neighbor pp.0.0.1 send-label
no auto-summary
no synchronization
bgp dampening 30
exit-address-family
Configuring the CSC-CE Routers Examples
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!VPNv4 session with CSC-PE2
MPLS VPN Carrier Supporting Carrier with BGP
Verifying Labels in the CSC-PE Routers Examples
The following example shows how to configure a CSC-CE router:
ip cef
!
mpls label protocol ldp
!
interface Loopback0
ip address cc.cc.cc.cc 255.255.255.255
!
interface Ethernet3/0
ip address pp.0.0.1 255.0.0.0
!
interface Ethernet4/0
ip address nn.0.0.2 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
mpls label protocol ldp
mpls ip
!
router ospf 200
log-adjacency-changes
auto-cost reference-bandwidth 1000
redistribute connected subnets
redistribute bgp 200 metric 3 subnets
passive-interface ATM1/0
passive-interface Ethernet3/0
network cc.cc.cc.cc 0.0.0.0 area 200
network nn.0.0.0 0.255.255.255 area 200
!
router bgp 200
no bgp default ipv4-unicast
bgp log-neighbor-changes
timers bgp 10 30
neighbor pp.0.0.2 remote-as 100
neighbor pp.0.0.2 update-source Ethernet3/0
no auto-summary
!
address-family ipv4
redistribute connected
redistribute ospf 200 metric 4 match internal
neighbor pp.0.0.2 activate
neighbor pp.0.0.2 send-label
no auto-summary
no synchronization
bgp dampening 30
exit-address-family
!Exchange routes
!learned from PE1
Verifying Labels in the CSC-PE Routers Examples
The following examples show how to verify the configurations of the CSC-PE routers.
Verify that the BGP session is up and running between the CSC-PE router and the CSC-CE router. Check
the data in the State/PfxRcd column to verify that prefixes are learned during each session.
Router# show ip bgp vpnv4 all summary
BBGP router identifier 10.5.5.5, local AS number 100
BGP table version is 52, main routing table version 52
12 network entries and 13 paths using 2232 bytes of memory
6 BGP path attribute entries using 336 bytes of memory
1 BGP AS-PATH entries using 24 bytes of memory
1 BGP extended community entries using 24 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
Dampening enabled. 0 history paths, 0 dampened paths
BGP activity 16/4 prefixes, 27/14 paths, scan interval 5 secs
Neighbor
V
AS
MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
10.5.5.5
4 100
7685
7686
52
0
0 21:17:04
6
10.0.0.2
4 200
7676
7678
52
0
0 21:16:43
7
MPLS Layer 3 VPNs Inter-AS and CSC Configuration Guide, Cisco IOS Release 12.4T
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MPLS VPN Carrier Supporting Carrier with BGP
Verifying Labels in the CSC-PE Routers Examples
Verify that the MPLS interfaces are up and running, and that LDP-enabled interfaces show that LDP is up
and running. LDP is turned off on the VRF because EBGP distributes the labels.
Router# show mpls interfaces all
Interface
IP
GigabitEthernet6/0
Yes (ldp)
VRF vpn1:
Ethernet3/1
No
Tunnel
No
Operational
Yes
No
Yes
Verify that the prefix for the local PE router is in the routing table of the CSC-PE router:
Router# show ip route vrf vpn2 10.5.5.5
Routing entry for 10.5.5.5/32
Known via "bgp 100", distance 20, metric 4
Tag 200, type external
Last update from pp.0.0.2 21:28:39 ago
Routing Descriptor Blocks:
* pp.0.0.2, from pp.0.0.2, 21:28:39 ago
Route metric is 4, traffic share count is 1
AS Hops 1, BGP network version 0
Verify that the prefix for the remote PE router is in the routing table of the CSC-PE router:
Router# show ip route vrf vpn2 10.5.5.5
Routing entry for 10.5.5.5/32
Known via "bgp 100", distance 200, metric 4
Tag 200, type internal
Last update from 10.1.0.0 21:27:39 ago
Routing Descriptor Blocks:
* 10.1.0.0 (Default-IP-Routing-Table), from 10.1.0.0, 21:27:39 ago
Route metric is 4, traffic share count is 1
AS Hops 1, BGP network version 0
Verify that the prefixes for the customer carrier MPLS VPN service provider networks are in the BGP
table, and have appropriate labels:
Router# show ip bgp vpnv4 vrf vpn2 labels
Network
Next Hop
In label/Out label
Route Distinguisher: 100:1 (vpn1)
cc.cc.cc.cc/32
pp.0.0.2
22/imp-null
bb.bb.bb.bb/32
pp.0.0.2
27/20
hh.hh.hh.hh/32
ee.ee.ee.ee
34/35
gg.gg.gg.gg/32
ee.ee.ee.ee
30/30
nn.0.0.0
pp.0.0.2
23/imp-null
ss.0.0.0
ee.ee.ee.ee
33/34
pp.0.0.0
pp.0.0.2
25/aggregate(vpn1)
Verify that the prefix of the PE router in the local customer carrier MPLS VPN service provider is in the
Cisco Express Forwarding table:
Router# show ip cef vrf vpn2 10.1.0.0
10.1.0.0/32, version 19, cached adjacency pp.0.0.2
0 packets, 0 bytes
tag information set
local tag: 27
fast tag rewrite with Et3/1, pp.0.0.2, tags imposed {20}
via pp.0.0.2, 0 dependencies, recursive
next hop pp.0.0.2, Ethernet3/1 via pp.0.0.2/32
valid cached adjacency
tag rewrite with Et3/1, pp.0.0.2, tags imposed {20}
Router# show ip cef vrf vpn2 10.1.0.0 detail
10.1.0.0/32, version 19, cached adjacency pp.0.0.2
0 packets, 0 bytes
tag information set
local tag: 27
fast tag rewrite with Et3/1, pp.0.0.2, tags imposed {20}
via pp.0.0.2, 0 dependencies, recursive
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MPLS VPN Carrier Supporting Carrier with BGP
Verifying Labels in the CSC-CE Routers Examples
next hop pp.0.0.2, Ethernet3/1 via pp.0.0.2/32
valid cached adjacency
tag rewrite with Et3/1, pp.0.0.2, tags imposed {20}
Verify that the prefix of the PE router in the local customer carrier MPLS VPN service provider is in the
MPLS forwarding table:
Router# show mpls forwarding-table vrf vpn2 10.1.0.0
Local Outgoing
Prefix
Bytes tag Outgoing
tag
tag or VC
or Tunnel Id
switched
interface
27
20
10.1.0.0/32[V]
958048
Et3/1
Next Hop
pp.0.0.2
Router# show mpls forwarding-table vrf vpn2 10.1.0.0 detail
Local Outgoing
Prefix
Bytes tag Outgoing
Next Hop
tag
tag or VC
or Tunnel Id
switched
interface
27
20 10.1.0.0/32[V]
958125
Et3/1
pp.0.0.2
MAC/Encaps=14/18, MTU=1500, Tag Stack{20}
00B04A74A05400B0C26E10558847 00014000
VPN route: vpn1
No output feature configured
Per-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Verify that the prefix of the PE router in the remote customer carrier MPLS VPN service provider is in the
Cisco Express Forwarding table:
Router# show ip cef vrf vpn2 10.3.0.0
10.3.0.0/32, version 25, cached adjacency rr.0.0.2
0 packets, 0 bytes
tag information set
local tag: 34
fast tag rewrite with Gi6/0, rr.0.0.2, tags imposed {35}
via ee.ee.ee.ee, 0 dependencies, recursive
next hop rr.0.0.2, GigabitEthernet6/0 via ee.ee.ee.ee/32
valid cached adjacency
tag rewrite with Gi6/0, rr.0.0.2, tags imposed {35}
Router# show ip cef vrf vpn2 10.3.0.0 detail
hh.hh.hh.hh/32, version 25, cached adjacency rr.0.0.2
0 packets, 0 bytes
tag information set
local tag: 34
fast tag rewrite with Gi6/0, rr.0.0.2, tags imposed {35}
via ee.ee.ee.ee, 0 dependencies, recursive
next hop rr.0.0.2, GigabitEthernet6/0 via ee.ee.ee.ee/32
valid cached adjacency
tag rewrite with Gi6/0, rr.0.0.2, tags imposed {35}
Verify that the prefix of the PE router in the remote customer carrier MPLS VPN service provider is in the
MPLS forwarding table:
Router# show mpls forwarding-table vrf vpn2 10.3.0.0
Local Outgoing
Prefix
Bytes tag Outgoing
tag
tag or VC
or Tunnel Id
switched
interface
34
35
hh.hh.hh.hh/32[V] 139034
Gi6/0
Next Hop
rr.0.0.2
Router# show mpls forwarding-table vrf vpn2 10.3.0.0 detail
Local Outgoing
Prefix
Bytes tag Outgoing
Next Hop
tag
tag or VC
or Tunnel Id
switched
interface
34
35
hh.hh.hh.hh/32[V] 139034
Gi6/0
rr.0.0.2
MAC/Encaps=14/18, MTU=1500, Tag Stack{35}
00B0C26E447000B0C26E10A88847 00023000
VPN route: vpn1
No output feature configured
Per-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Verifying Labels in the CSC-CE Routers Examples
The following examples show how to verify the configurations of the CSC-CE routers.
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MPLS VPN Carrier Supporting Carrier with BGP
Verifying Labels in the CSC-CE Routers Examples
Verify that the BGP session is up and running:
Router# show ip bgp summary
BGP router identifier cc.cc.cc.cc, local AS number 200
BGP table version is 35, main routing table version 35
14 network entries and 14 paths using 2030 bytes of memory
3 BGP path attribute entries using 168 bytes of memory
1 BGP AS-PATH entries using 24 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
Dampening enabled. 1 history paths, 0 dampened paths
BGP activity 17/67 prefixes, 29/15 paths, scan interval 60 secs
Neighbor
V
AS MsgRcvd MsgSent
TblVer InQ OutQ Up/Down State/PfxRcd
pp.0.0.1
4
100
7615
7613
35
0
0 21:06:19
5
Verify that the loopback address of the local PE router is in the routing table:
Router# show ip route 10.1.0.0
Routing entry for 10.1.0.0/32
Known via "ospf 200", distance 110, metric 101, type intra area
Redistributing via bgp 200
Advertised by bgp 200 metric 4 match internal
Last update from nn.0.0.1 on Ethernet4/0, 00:34:08 ago
Routing Descriptor Blocks:
* nn.0.0.1, from bb.bb.bb.bb, 00:34:08 ago, via Ethernet4/0
Route metric is 101, traffic share count is 1
Verify that the loopback address of the remote PE router is in the routing table:
Router# show ip route 10.5.5.5
Routing entry for 10.5.5.5/32
Known via "bgp 200", distance 20, metric 0
Tag 100, type external
Redistributing via ospf 200
Advertised by ospf 200 metric 3 subnets
Last update from pp.0.0.1 00:45:16 ago
Routing Descriptor Blocks:
* pp.0.0.1, from pp.0.0.1, 00:45:16 ago
Route metric is 0, traffic share count is 1
AS Hops 2, BGP network version 0
Verify that the prefix of the local PE router is in the MPLS LDP bindings:
Router# show mpls ldp bindings 10.1.0.0 255.255.255.255
tib entry: 10.1.0.0/32, rev 20
local binding: tag: 20
remote binding: tsr: 10.1.0.0:0, tag: imp-null
Verify that the prefix of the local PE router is in the Cisco Express Forwarding table:
Router# show ip cef 10.1.0.0
10.1.0.0/32, version 46, cached adjacency nn.0.0.1
0 packets, 0 bytes
tag information set
local tag: 20
via nn.0.0.1, Ethernet4/0, 0 dependencies
next hop nn.0.0.1, Ethernet4/0
unresolved
valid cached adjacency
tag rewrite with Et4/0, nn.0.0.1, tags imposed {}
Verify that the prefix of the local PE router is in the MPLS forwarding table:
Router# show mpls forwarding-table 10.1.0.0
Local Outgoing
Prefix
Bytes tag
tag
tag or VC
or Tunnel Id
switched
20
Pop tag
bb.bb.bb.bb/32
893397
Outgoing
interface
Et4/0
Router# show mpls forwarding-table 10.1.0.0 detail
Local Outgoing
Prefix
Bytes tag Outgoing
MPLS Layer 3 VPNs Inter-AS and CSC Configuration Guide, Cisco IOS Release 12.4T
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Next Hop
nn.0.0.1
Next Hop
Configuring the Customer Carrier Network Examples
Verifying IP Connectivity in the Customer Carrier Example
tag
20
tag or VC
or Tunnel Id
switched
interface
Pop tag
bb.bb.bb.bb/32
893524
Et4/0
nn.0.0.1
MAC/Encaps=14/14, MTU=1504, Tag Stack{}
00074F83685400B04A74A0708847
No output feature configured
Per-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Verify that the BGP routing table contains labels for prefixes in the customer carrier MPLS VPN service
provider networks:
Router# show ip bgp labels
Network
Next Hop
cc.cc.cc.cc/32
0.0.0.0
bb.bb.bb.bb/32
nn.0.0.1
hh.hh.hh.hh/32
pp.0.0.1
gg.gg.gg.gg/32
pp.0.0.1
nn.0.0.0
0.0.0.0
ss.0.0.0
pp.0.0.1
pp.0.0.0
0.0.0.0
pp.0.0.1/32
0.0.0.0
In Label/Out Label
imp-null/exp-null
20/exp-null
26/34
23/30
imp-null/exp-null
25/33
imp-null/exp-null
16/exp-null
Verify that the prefix of the remote PE router is in the Cisco Express Forwarding table:
Router# show ip cef 10.5.5.5
10.5.5.5/32, version 54, cached adjacency pp.0.0.1
0 packets, 0 bytes
tag information set
local tag: 26
fast tag rewrite with Et3/0, pp.0.0.1, tags imposed {34}
via pp.0.0.1, 0 dependencies, recursive
next hop pp.0.0.1, Ethernet3/0 via pp.0.0.1/32
valid cached adjacency
tag rewrite with Et3/0, pp.0.0.1, tags imposed {34}
Verify that the prefix of the remote PE router is in the MPLS forwarding table:
Router# show mpls forwarding-table 10.5.5.5
Local Outgoing
Prefix
Bytes tag
tag
tag or VC
or Tunnel Id
switched
26
34
hh.hh.hh.hh/32
81786
Outgoing
interface
Et3/0
Next Hop
pp.0.0.1
Router# show mpls forwarding-table 10.5.5.5 detail
Local Outgoing
Prefix
Bytes tag Outgoing
Next Hop
tag
tag or VC
or Tunnel Id
switched
interface
26
34
hh.hh.hh.hh/32
81863
Et3/0
pp.0.0.1
MAC/Encaps=14/18, MTU=1500, Tag Stack{34}
00B0C26E105500B04A74A0548847 00022000
No output feature configured
Per-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Configuring the Customer Carrier Network Examples
Customer carrier configuration and verification examples in this section include:
•
•
Verifying IP Connectivity in the Customer Carrier Example, page 43
Configuring a Customer Carrier Core Router as a Route Reflector Example, page 44
Verifying IP Connectivity in the Customer Carrier Example
Verify the connectivity from one customer carrier core router to another (from CE1 to CE2) by entering the
following command:
Router# ping 10.2.0.0
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to jj.jj.jj.jj, timeout is 2 seconds:
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Configuring a Customer Carrier Core Router as a Route Reflector Example
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 8/9/12 ms
Verify the path that a packet goes through on its way to its final destination from CE1 to CE2:
Router# trace 10.2.0.0
Type escape sequence to abort.
Tracing the route to 10.2.0.0
1 mm.0.0.2 0 msec 0 msec 4 msec
2 nn.0.0.2 [MPLS: Labels 20/21 Exp 0] 8
3 pp.0.0.2 [MPLS: Labels 28/21 Exp 0] 8
4 ss.0.0.1 [MPLS: Labels 17/21 Exp 0] 8
5 ss.0.0.2 [MPLS: Labels 16/21 Exp 0] 8
6 tt.0.0.1 [AS 200] [MPLS: Label 21 Exp
7 tt.0.0.2 [AS 200] 8 msec 4 msec *
msec
msec
msec
msec
0] 8
8 msec
8 msec
8 msec
8 msec
msec 8
12 msec
12 msec
12 msec
12 msec
msec 8 msec
Verify the path that a packet goes through on its way to its final destination from CE2 to CE1:
Router# trace 10.1.0.0
Type escape sequence to abort.
Tracing the route to 10.1.0.0
1 tt.0.0.1 0 msec 0 msec 0 msec
2 qq.0.0.2 [MPLS: Labels 18/21 Exp 0] 8 msec 12 msec 12 msec
3 ss.0.0.1 [MPLS: Labels 28/21 Exp 0] 8 msec 8 msec 8 msec
4 pp.0.0.2 [MPLS: Labels 17/21 Exp 0] 12 msec 8 msec 8 msec
5 pp.0.0.1 [MPLS: Labels 16/21 Exp 0] 12 msec 12 msec 8 msec
6 mm.0.0.2 [AS 200] [MPLS: Label 21 Exp 0] 12 msec 8 msec 12 msec
7 mm.0.0.1 [AS 200] 4 msec 4 msec *
Configuring a Customer Carrier Core Router as a Route Reflector Example
The following example shows how to use an address family to configure internal BGP peer 10.1.1.1 as a
route-reflector client for both unicast and multicast prefixes:
router bgp 200
address-family vpnv4
neighbor 10.1.1.1 activate
neighbor 10.1.1.1 route-reflector-client
router bgp 100
address-family vpnv4
neighbor xx.xx.xx.xx activate
neighbor xx.xx.xx.xx route-reflector-client
! xx.xx.xx,xx is a PE router
neighbor xx.xx.xx.xx send-community extended
exit address-family
! You need to configure your peer BGP neighbor.
Configuring the Customer Site for Hierarchical VPNs Examples
This section contains the following configuration and verification examples for the customer site:
•
•
•
•
Configuring PE Routers for Hierarchical VPNs Examples, page 44
Verifying Labels in Each PE Router for Hierarchical VPNs Examples, page 45
Configuring CE Routers for Hierarchical VPNs Examples, page 46
Verifying IP Connectivity in the Customer Site Examples, page 47
Configuring PE Routers for Hierarchical VPNs Examples
This example shows how to configure a PE router:
ip cef
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Verifying Labels in Each PE Router for Hierarchical VPNs Examples
!
ip vrf vpn2
rd 200:1
route-target export 200:1
route-target import 200:1
mpls label protocol ldp
!
interface Loopback0
ip address bb.bb.bb.bb 255.255.255.255
!
interface Ethernet3/0
ip address nn.0.0.1 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
mpls label protocol ldp
mpls ip
!
interface Ethernet3/3
ip vrf forwarding vpn2
ip address mm.0.0.2 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
!
router ospf 200
log-adjacency-changes
auto-cost reference-bandwidth 1000
redistribute connected subnets
passive-interface Ethernet3/3
network bb.bb.bb.bb 0.0.0.0 area 200
network nn.0.0.0 0.255.255.255 area 200
!
router bgp 200
no bgp default ipv4-unicast
bgp log-neighbor-changes
timers bgp 10 30
neighbor hh.hh.hh.hh remote-as 200
neighbor hh.hh.hh.hh update-source Loopback0
!
address-family vpnv4
neighbor hh.hh.hh.hh activate
neighbor hh.hh.hh.hh send-community extended
bgp dampening 30
exit-address-family
!
address-family ipv4 vrf vpn2
neighbor mm.0.0.1 remote-as 300
neighbor mm.0.0.1 activate
neighbor mm.0.0.1 as-override
neighbor mm.0.0.1 advertisement-interval 5
no auto-summary
no synchronization
bgp dampening 30
exit-address-family
!VPNv4 session with PE2
Verifying Labels in Each PE Router for Hierarchical VPNs Examples
The following examples show how to verify the configuration of PE router in hierarchical VPNs.
Verify that the loopback address of the local CE router is in the routing table of the PE1 router:
Router# show ip route vrf vpn2 10.2.2.2
Routing entry for 10.2.2.2/32
Known via "bgp 200", distance 20, metric 0
Tag 300, type external
Last update from mm.0.0.2 20:36:59 ago
Routing Descriptor Blocks:
* mm.0.0.2, from mm.0.0.2, 20:36:59 ago
Route metric is 0, traffic share count is 1
AS Hops 1, BGP network version 0
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Configuring CE Routers for Hierarchical VPNs Examples
Verify that the prefix for the local CE router is in the MPLS forwarding table, and that the prefix is
untagged:
Router# show mpls forwarding-table vrf vpn2 10.2.2.2
Local Outgoing
Prefix
Bytes tag Outgoing
tag
tag or VC
or Tunnel Id
switched
interface
23
Untagged
aa.aa.aa.aa/32[V] 0
Et3/3
Next Hop
mm.0.0.2
Verify that the prefix of the remote PE router is in the Cisco Express Forwarding table:
Router# show ip cef 10.5.5.5
10.5.5.5/32, version 31, cached adjacency nn.0.0.2
0 packets, 0 bytes
tag information set
local tag: 31
fast tag rewrite with Et3/0, nn.0.0.2, tags imposed {26}
via nn.0.0.2, Ethernet3/0, 2 dependencies
next hop nn.0.0.2, Ethernet3/0
unresolved
valid cached adjacency
tag rewrite with Et3/0, nn.0.0.2, tags imposed {26}
Verify that the loopback address of the remote CE router is in the routing table:
Router# show ip route vrf vpn2 10.2.0.0
Routing entry for 10.2.0.0/32
Known via "bgp 200", distance 200, metric 0
Tag 300, type internal
Last update from hh.hh.hh.hh 20:38:49 ago
Routing Descriptor Blocks:
* hh.hh.hh.hh (Default-IP-Routing-Table), from hh.hh.hh.hh, 20:38:49 ago
Route metric is 0, traffic share count is 1
AS Hops 1, BGP network version 0
Verify that the prefix of the remote CE router is in the MPLS forwarding table, and that an outgoing
interface exists:
Router# show mpls forwarding-table vrf vpn2 10.2.0.0
Local Outgoing
Prefix
Bytes tag Outgoing
tag
tag or VC
or Tunnel Id
switched
interface
None
26
jj.jj.jj.jj/32
0
Et3/0
Next Hop
nn.0.0.2
Verify that the prefix of the remote CE router is in the Cisco Express Forwarding table:
Router# show ip cef vrf vpn2 10.2.0.0
10.2.0.0/32, version 12, cached adjacency nn.0.0.2
0 packets, 0 bytes
tag information set
local tag: VPN route head
fast tag rewrite with Et3/0, nn.0.0.2, tags imposed {26 32}
via hh.hh.hh.hh, 0 dependencies, recursive
next hop nn.0.0.2, Ethernet3/0 via hh.hh.hh.hh/32
valid cached adjacency
tag rewrite with Et3/0, nn.0.0.2, tags imposed {26 32}
Verify that the prefix of the local PE router is in the Cisco Express Forwarding table:
Router# show ip cef 10.1.0.0
10.1.0.0/32, version 9, connected, receive
tag information set
local tag: implicit-null
Configuring CE Routers for Hierarchical VPNs Examples
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Verifying IP Connectivity in the Customer Site Examples
The following example shows how to configure a CE router:
ip cef distributed
interface Loopback0
ip address 10.3.0.0 255.255.255.255
!
interface FastEthernet0/3/3
ip address mm.0.0.1 255.0.0.0
!
router bgp 300
no synchronization
bgp log-neighbor-changes
timers bgp 10 30
redistribute connected
neighbor mm.0.0.2 remote-as 200
neighbor mm.0.0.2 advertisement-interval 5
no auto-summary
!Redistributing routes into BGP
!to send to PE1
Verifying IP Connectivity in the Customer Site Examples
The following examples show how to verify IP connectivity at the customer site.
Verify that the loopback address of the remote CE router, learned from the PE router, is in the routing table
of the local router:
Router# show ip route 10.2.0.0
Routing entry for 10.2.0.0/32
Known via "bgp 300", distance 20, metric 0
Tag 200, type external
Redistributing via ospf 300
Advertised by ospf 300 subnets
Last update from mm.0.0.1 20:29:35 ago
Routing Descriptor Blocks:
* mm.0.0.1, from mm.0.0.1, 20:29:35 ago
Route metric is 0, traffic share count is 1
AS Hops 2
Additional References
Related Documents
Related Topic
Document Title
LDP
MPLS Label Distribution Protocol
MPLS
MPLS Product Literature
Standards
Standard
Title
No new or modified standards are supported by this -feature, and support for existing standards has not
been modified by this feature.
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Additional References
MIBs
MIB
MIBs Link
No new or modified MIBs are supported by this
feature, and support for existing MIBs has not been
modified by this feature.
To locate and download MIBs for selected
platforms, Cisco software releases, and feature sets,
use Cisco MIB Locator found at the following
URL:
http://www.cisco.com/go/mibs
RFCs
RFC
Title
RFC 1164
Application of the Border Gateway Protocol in the
Internet
RFC 1171
A Border Gateway Protocol 4
RFC 1700
Assigned Numbers
RFC 1966
BGP Route Reflection: An Alternative to Full Mesh
IBGP
RFC 2283
Multiprotocol Extensions for BGP-4
RFC 2547
BGP/MPLS VPNs
RFC 2842
Capabilities Advertisement with BGP-4
RFC 2858
Multiprotocol Extensions for BGP-4
RFC 3107
Carrying Label Information in BGP-4
Technical Assistance
Description
Link
The Cisco Support website provides extensive
http://www.cisco.com/techsupport
online resources, including documentation and tools
for troubleshooting and resolving technical issues
with Cisco products and technologies.
To receive security and technical information about
your products, you can subscribe to various
services, such as the Product Alert Tool (accessed
from Field Notices), the Cisco Technical Services
Newsletter, and Really Simple Syndication (RSS)
Feeds.
Access to most tools on the Cisco Support website
requires a Cisco.com user ID and password.
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Feature Information for MPLS VPN CSC with BGP
Feature Information for MPLS VPN CSC with BGP
The following table provides release information about the feature or features described in this module.
This table lists only the software release that introduced support for a given feature in a given software
release train. Unless noted otherwise, subsequent releases of that software release train also support that
feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support.
To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Table 2
Feature Information for MPLS VPN CSC with BGP
Feature Name
Releases
Feature Information
MPLS VPN--Carrier Supporting
Carrier--IPv4 BGP Label
Distribution
12.0(21)ST
This feature enables you to create
an MPLS VPN CSC network that
uses BGP to transport routes and
MPLS labels.
12.0(22)S
12.0(23)S
12.2(13)T
12.0(24)S
12.2(14)S
12.0(27)S
12.0(29)S
In 12.0(21)ST, this feature was
introduced.
In 12.0(22)S, this feature was
integrated.
In 12.0(23)S, this feature was
integrated.
In 12.2(13)T, this feature was
integrated.
12.0(24)S, this feature was
integrated.
In 12.2(14)S, this feature was
integrated.
In 12.0(27)S, this feature was
integrated.
In 12.0(29)S, this feature was
integrated.
This feature uses no new or
modified commands.
Glossary
ASBR -- Autonomous System Boundary router. A router that connects one autonomous system to another.
autonomous system --A collection of networks under a common administration sharing a common routing
strategy.
BGP --Border Gateway Protocol. An interdomain routing protocol that exchanges network reachability
information with other BGP systems (which may be within the same autonomous system or between
multiple autonomous systems).
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Glossary
CE router--customer edge router. A router that is part of a customer network and that interfaces to a
provider edge (PE) router. CE routers do not recognize associated MPLS VPNs.
CSC --Carrier Supporting Carrier. A hierarchical VPN model that allows small service providers, or
customer carriers, to interconnect their IP or MPLS networks over an MPLS backbone. This eliminates the
need for customer carriers to build and maintain their own MPLS backbone.
eBGP --external Border Gateway Protocol. A BGP between routers located within different autonomous
systems. When two routers, located in different autonomous systems, are more than one hop away from one
another, the eBGP session between the two routers is considered a multihop BGP.
edge router--A router that is at the edge of the network. It defines the boundary of the MPLS network. It
receives and transmits packets. Also referred to as edge label switch router and label edge router.
iBGP --internal Border Gateway Protocol. A BGP between routers within the same autonomous system.
IGP --Interior Gateway Protocol. Internet protocol used to exchange routing information within a single
autonomous system. Examples of common Internet IGP protocols include IGRP, OSPF, IS-IS, and RIP.
IP --Internet Protocol. Network layer protocol in the TCP/IP stack offering a connectionless internetwork
service. IP provides features for addressing, type-of-service specification, fragmentation and reassembly,
and security. Defined in RFC 791.
LDP --Label Distribution Protocol. A standard protocol between MPLS-enabled routers to negotiate the
labels (addresses) used to forward packets.
LFIB --Label Forwarding Information Base. Data structure used in MPLS to hold information about
incoming and outgoing labels and associated Forwarding Equivalence Class (FEC) packets.
MP-BGP --Multiprotocol BGP.
MPLS --Multiprotocol Label Switching. The name of the IETF working group responsible for label
switching, and the name of the label switching approach it has standardized.
NLRI --Network Layer Reachability Information. The BGP sends routing update messages containing
NLRI to describe a route and how to get there. In this context, an NLRI is a prefix. A BGP update message
carries one or more NLRI prefixes and the attributes of a route for the NLRI prefixes; the route attributes
include a BGP next hop gateway address and extended community values.
NSF --Nonstop forwarding enables routers to continuously forward IP packets following a Route Processor
takeover or switchover to another Route Processor. NSF maintains and updates Layer 3 routing and
forwarding information in the backup Route Processor to ensure that IP packets and routing protocol
information are forwarded continuously during the switchover and route convergence process.
PE router--provider edge router. A router that is part of a service provider’s network. It is connected to a
customer edge (CE) router. All MPLS VPN processing occurs in the PE router.
QoS --quality of service. Measure of performance for a transmission system that indicates its transmission
quality and service availability.
RD --route distinguisher. An 8-byte value that is concatenated with an IPv4 prefix to create a unique VPNIPv4 prefix.
RT --route target. Extended community attribute used to identify the VRF routing table into which a prefix
is imported.
SLA --Service Level Agreement given to VPN subscribers.
VPN --Virtual Private Network. A secure MPLS-based network that shares resources on one or more
physical networks (typically implemented by one or more service providers). A VPN contains
geographically dispersed sites that can communicate securely over a shared backbone network.
VRF --VPN routing and forwarding instance. Routing information that defines a VPN site that is attached
to a PE router. A VRF consists of an IP routing table, a derived forwarding table, a set of interfaces that use
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MPLS VPN Carrier Supporting Carrier with BGP
the forwarding table, and a set of rules and routing protocols that determine what goes into the forwarding
table.
Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S.
and other countries. To view a list of Cisco trademarks, go to this URL: www.cisco.com/go/trademarks.
Third-party trademarks mentioned are the property of their respective owners. The use of the word partner
does not imply a partnership relationship between Cisco and any other company. (1110R)
Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be
actual addresses and phone numbers. Any examples, command display output, network topology diagrams,
and other figures included in the document are shown for illustrative purposes only. Any use of actual IP
addresses or phone numbers in illustrative content is unintentional and coincidental.
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MPLS VPN Carrier Supporting Carrier Using
LDP and an IGP
Multiprotocol Label Switching (MPLS) Virtual Private Network (VPN) Carrier Supporting Carrier (CSC)
enables one MPLS VPN-based service provider to allow other service providers to use a segment of its
backbone network. This module explains how to configure the MPLS VPN CSC network using MPLS
Label Distribution Protocol (LDP) to distribute MPLS labels and an Interior Gateway Protocol (IGP) to
distribute routes.
•
•
•
•
•
•
•
•
•
Finding Feature Information, page 53
Prerequisites for MPLS VPN CSC with LDP and IGP, page 53
Restrictions for MPLS VPN CSC with LDP and IGP, page 54
Information About MPLS VPN CSC with LDP and IGP, page 55
How to Configure MPLS VPN CSC with LDP and IGP, page 61
Configuration Examples for MPLS VPN CSC with LDP and IGP, page 72
Additional References, page 114
Feature Information for MPLS VPN CSC with LDP and IGP, page 115
Glossary, page 116
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest feature
information and caveats, see the release notes for your platform and software release. To find information
about the features documented in this module, and to see a list of the releases in which each feature is
supported, see the Feature Information Table at the end of this document.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support.
To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Prerequisites for MPLS VPN CSC with LDP and IGP
•
•
The provider edge (PE) routers of the backbone carrier require 128 MB of memory.
The backbone carrier must enable the PE router to check that the packets it receives from the customer
edge (CE) router contain only the labels that the PE router advertised to the CE router. This prevents
data spoofing, which occurs when a packet from an unrecognized IP address is sent to a router.
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Restrictions for MPLS VPN CSC with LDP and IGP
Restrictions for MPLS VPN CSC with LDP and IGP
The following features are not supported with this feature:
•
•
•
•
•
ATM MPLS
Carrier supporting carrier traffic engineering
Carrier supporting carrier quality of service (QoS)
RSVP aggregation
VPN Multicast between the customer carrier and the backbone carrier network
The following router platforms are supported on the edge of the MPLS VPN:
•
•
•
Cisco 7200 series
Cisco 7500 series
Cisco 12000 series
See the table below for Cisco 12000 series line card support added for Cisco IOS releases.
Table 3
Cisco12000 Series Line Card Support Added for Cisco IOS Releases
Type
Line Cards
Cisco IOS Release Added
Packet over SONET (POS)
4-Port OC-3 POS
12.0(16)ST
1-Port OC-12 POS
12.0(21)ST
8-Port OC-3 POS
12.0(22)S
16-Port OC-3 POS
4-Port OC-12 POS
1-Port OC-48 POS
4-Port OC-3 POS ISE
8-Port OC-3 POS ISE
16 x OC-3 POS ISE
4 Port OC-12 POS ISE
1-Port OC-48 POS ISE
Electrical Interface
6- Port DS3
12.0(16)ST
12- Port DS3
12.0(21)ST
6-Port E3
ATM
4-Port OC-3 ATM
1-Port OC12 ATM
4-Port OC-12 ATM
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12.0(22)S
MPLS VPN CSC Introduction
Information About MPLS VPN CSC with LDP and IGP
Type
Line Cards
Cisco IOS Release Added
Channelized Interface
2-Port CHOC-3
12.0(22)S
6-Port Ch T3 (DS1)
1-Port CHOC-12 (DS3)
1-Port CHOC-12 (OC-3)
4-Port CHOC-12 ISE
1-Port CHOC-48 ISE
Information About MPLS VPN CSC with LDP and IGP
•
•
•
•
MPLS VPN CSC Introduction, page 2
Benefits of Implementing MPLS VPN CSC, page 2
Configuration Options for MPLS VPN CSC with LDP and IGP, page 56
Customer Carrier Is a BGP MPLS VPN Service Provider, page 59
MPLS VPN CSC Introduction
Carrier supporting carrier is where one service provider allows another service provider to use a segment of
its backbone network. The service provider that provides the segment of the backbone network to the other
provider is called the backbone carrier. The service provider that uses the segment of the backbone network
is called the customer carrier.
A backbone carrier offers Border Gateway Protocol and Multiprotocol Label Switching (BGP/MPLS) VPN
services. The customer carrier can be either:
•
•
An Internet service provider (ISP)
A BGP/MPLS VPN service provider
Benefits of Implementing MPLS VPN CSC
The MPLS VPN CSC network provides the following benefits to service providers who are backbone
carriers and to customer carriers.
Benefits to the Backbone Carrier
•
•
•
The backbone carrier can accommodate many customer carriers and give them access to its backbone.
The backbone carrier does not need to create and maintain separate backbones for its customer
carriers. Using one backbone network to support multiple customer carriers simplifies the backbone
carrier’s VPN operations. The backbone carrier uses a consistent method for managing and
maintaining the backbone network. This is also cheaper and more efficient than maintaining separate
backbones.
The MPLS VPN carrier supporting carrier feature is scalable. Carrier supporting carrier can change the
VPN to meet changing bandwidth and connectivity needs. The feature can accommodate unplanned
growth and changes. The carrier supporting carrier feature enables tens of thousands of VPNs to be set
up over the same network, and it allows a service provider to offer both VPN and Internet services.
The MPLS VPN carrier supporting carrier feature is a flexible solution. The backbone carrier can
accommodate many types of customer carriers. The backbone carrier can accept customer carriers who
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Configuration Options for MPLS VPN CSC with LDP and IGP
Customer Carrier Is an ISP
are ISPs or VPN service providers or both. The backbone carrier can accommodate customer carriers
that require security and various bandwidths.
Benefits to the Customer Carriers
•
•
•
•
The MPLS VPN carrier supporting carrier feature removes from the customer carrier the burden of
configuring, operating, and maintaining its own backbone. The customer carrier uses the backbone
network of a backbone carrier, but the backbone carrier is responsible for network maintenance and
operation.
Customer carriers who use the VPN services provided by the backbone carrier receive the same level
of security that Frame Relay or ATM-based VPNs provide. Customer carriers can also use IPSec in
their VPNs for a higher level of security; it is completely transparent to the backbone carrier.
Customer carriers can use any link layer technology (SONET, DSL, Frame Relay, and so on) to
connect the CE routers to the PE routers and the PE routers to the P routers. The MPLS VPN carrier
supporting carrier feature is link layer independent. The CE routers and PE routers use IP to
communicate, and the backbone carrier uses MPLS.
The customer carrier can use any addressing scheme and still be supported by a backbone carrier. The
customer address space and routing information are independent of the address space and routing
information of other customer carriers or the backbone provider.
Configuration Options for MPLS VPN CSC with LDP and IGP
The backbone carrier offers BGP and MPLS VPN services. The customer carrier can be one of the two
types of service providers described in the following sections, which explain how the backbone and
customer carriers distribute IPv4 routes and MPLS labels.
•
Customer Carrier Is an ISP, page 56
Customer Carrier Is an ISP
This section explains how a BGP/MPLS VPN service provider (backbone carrier) can provide a segment of
its backbone network to a customer who is an ISP.
Consider the following example:
An ISP has two sites: one in California, the other in Maine. Each site is a point of presence (POP). The ISP
wants to connect these sites using a VPN service provided by a backbone carrier. The figure below
illustrates this situation.
Figure 5
Sample BGP/MPLS Backbone Carrier Supporting an ISP
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Customer Carrier Is an ISP
Note
The CE routers in the figures are CE routers to the backbone carrier. However, they are PE routers to the
customer carrier.
In this example, only the backbone carrier uses MPLS. The customer carrier (ISP) uses only IP. As a result,
the backbone carrier must carry all the Internet routes of the customer carrier, which could be as many as
100,000 routes. This poses a scalability problem for the backbone carrier. To solve the scalability problem,
the backbone carrier is configured as follows:
•
•
The backbone carrier allows only internal routes of the customer carrier (IGP routes) to be exchanged
between the CE routers of the customer carrier and the PE routers of the backbone carrier.
MPLS is enabled on the interface between the CE router of the customer carrier and the PE router of
the backbone carrier.
Internal and external routes are differentiated this way:
•
•
Internal routes go to any of the routers within the ISP.
External routes go to the Internet.
The number of internal routes is much lower than the number of external routes. Restricting the routes
between the CE routers of the customer carrier and the PE routers of the backbone carrier significantly
reduces the number of routes that the PE router needs to maintain.
Because the PE routers do not have to carry external routes in the VRF routing table, they can use the
incoming label in the packet to forward the customer carrier Internet traffic. Adding MPLS to the routers
provides a consistent method of transporting packets from the customer carrier to the backbone carrier.
MPLS allows the exchange of an MPLS label between the PE and the CE routers for every internal
customer carrier route. The routers in the customer carrier have all the external routes either through
internal Border Gateway Protocol (iBGP) or route redistribution to provide Internet connectivity. The
figure below shows how information is exchanged when the network is configured in this manner.
Figure 6
Backbone Carrier Exchanging Routing Information with a Customer Carrier Who Is an ISP
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Customer Carrier Is an ISP
In the figure below, routes are created between the backbone carrier and the customer carrier sites. ASBR2
receives an Internet route that originated outside the network. All routers in the ISP sites have all the
external routes through IBGP connections among them.
Figure 7
Establishing a Route Between a Backbone Carrier and a Customer Carrier Who Is an ISP
The table below describes the process of establishing the route, which can be divided into two distinct
steps:
•
•
The backbone carrier propagates the IGP information of the customer carrier, which enables the
customer carrier routers to reach all the customer carrier routers in the remote sites.
Once the routers of the customer carriers in different sites are reachable, external routes can be
propagated in the customer carrier sites, using IBGP without using the backbone carrier routers.
Table 4
Establishing a Route Between the Backbone Carrier and the Customer Carrier ISP
Step
Description
1
CSC-CE2 sends the internal routes within site 2 to
CSC-PE2. The routes include the route to ASBR2.
2
CSC-PE2 sends the routing information for site 2 to
CSC-PE1, using MPLS VPN processes. CSC-PE1
gets one label (called L3), which is associated with
the route to the VPN-IP address for ASBR2. CSCPE1 gets another label (called L2), which is
associated with the route to CSC-PE2.
3
CSC-PE1 sends the routing information associated
with internal routes from site 2 to CSC-CE1. CSCPE1 also sends the label binding information. As a
result, CSC-CE1 gets the route to ASBR2 with
CSC-PE1 as the next hop. The label associated with
that route is called L1.
4
CSC-CE1 distributes the routing information
through site 1. Every router in site 1 gets a route for
every internal destination in site 2. Therefore, every
router in site 1 can reach routers in site 2 and learn
external routes through IBGP.
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Customer Carrier Is a BGP MPLS VPN Service Provider
Customer Carrier Is an ISP
Step
Description
5
ASBR2 receives an Internet route.
6
The IBGP sessions exchange the external routing
information of the ISP, including a route to the
Internet. Every router in site 1 knows a route to the
Internet, with ASBR2 as the next hop of that route.
Customer Carrier Is a BGP MPLS VPN Service Provider
When a backbone carrier and the customer carrier both provide BGP/MPLS VPN services, the method of
transporting data is different from when a customer carrier provides only ISP services. The following list
highlights those differences:
•
•
When a customer carrier provides BGP/MPLS VPN services, its external routes are VPN-IPv4 routes.
When a customer carrier is an ISP, its external routes are IP routes.
When a customer carrier provides BGP/MPLS VPN services, every site within the customer carrier
must use MPLS. When a customer carrier is an ISP, the sites do not need to use MPLS.
The figure below shows how information is exchanged when MPLS VPN services reside on all customer
carrier sites and on the backbone carrier.
Figure 8
Backbone Carrier Exchanging Information with a Customer Carrier Who Is an MPLS VPN Service
Provider
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Customer Carrier Is an ISP
In the example shown in the figure below, routes are created between the backbone carrier and the
customer carrier sites.
Figure 9
Establishing a Route Between a Backbone Carrier and a Customer Carrier Who Is an MPLS VPN
Service Provider
The table below describes the process of establishing the route.
Table 5
Establishing a Route Between the Backbone Carrier and Customer Carrier Site
Step
Description
1
CE2 sends all the internal routes within site 2 to
CSC-PE2.
2
CSC-PE2 sends the routing information for site 2 to
CSC-PE1, using MPLS VPN processes. CSC-PE1
gets one label (called L3), which is associated with
the route to the VPN-IP address for PE2. CSC-PE1
gets another label (called L2), which is associated
with the route to CSC-PE2.
3
CSC-PE1 sends the routing information associated
with internal routes from site 2 to CSC-CE1. CSCPE1 also sends the label binding information. As a
result, CSC-CE1 gets the route to PE2 with CSCPE1 as the next hop. The label associated with that
route is called L1.
4
CE1 distributes the routing and labeling
information through site 1. Every router in site 1
gets a route for every internal destination in site 2.
Therefore, PE1 can establish an MP-IBGP session
with PE2.
5
CE2 advertises the internal routes of MPLS VPN
site 2 to PE2.
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Configuring the Backbone Carrier Core
How to Configure MPLS VPN CSC with LDP and IGP
Step
Description
6
PE2 allocates labels for all the VPN routes (regular
MPLS VPN functionality) and advertises the labels
to PE1, using MP-IBGP.
7
PE1 can forward traffic from VPN site 1 that is
destined for VPN site 2.
How to Configure MPLS VPN CSC with LDP and IGP
•
•
•
Configuring the Backbone Carrier Core, page 61
Configuring the CSC-PE and CSC-CE Routers, page 68
Verifying the Carrier Supporting Carrier Configuration, page 71
Configuring the Backbone Carrier Core
Configuring the backbone carrier core requires configuring connectivity and routing functions for the CSC
core and the CSC-PE routers.
Configuring and verifying the CSC core (backbone carrier) involves the following tasks:
•
•
•
•
Prerequisites, page 61
Verifying IP Connectivity and LDP Configuration in the CSC Core, page 61
Configuring VRFs for CSC-PE Routers, page 64
Configuring Multiprotocol BGP for VPN Connectivity in the Backbone Carrier, page 11
Prerequisites
Before you configure a backbone carrier core, configure the following on the CSC core routers:
•
•
An IGP routing protocol--BGP, OSPF, IS-IS, EIGRP, static, and so on. For information, see
Configuring a Basic BGP Network, Configuring OSPF, Configuring a Basic IS-IS Network, and
Configuring EIGRP.
Label Distribution Protocol (LDP). For information, see MPLS Label Distribution Protocol.
Verifying IP Connectivity and LDP Configuration in the CSC Core
Perform this task to verify IP connectivity and LDP configuration in the CSC core. For a configuration
example for this task, see the Verifying IP Connectivity and LDP Configuration in the CSC Core, page 61.
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Verifying IP Connectivity and LDP Configuration in the CSC Core
SUMMARY STEPS
1. enable
2. ping [protocol] {host-name | system-address}
3. trace [protocol] [destination]
4. show mpls forwarding-table [network {mask | length} | labels label [-label] | interface interface |
next-hop address | lsp-tunnel [tunnel-id]] [vrf vrf-name] [detail]
5. show mpls ldp discovery [vrf vrf-name | all]
6. show mpls ldp neighbor [[vrf vrf-name] [address | interface] [detail] | all]
7. show ip cef [vrf vrf-name] [network [mask]] [longer-prefixes] [detail]
8. show mpls interfaces [[vrf vrf-name] [interface] [detail] |all]
9. show ip route
10. disable
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 ping [protocol] {host-name | system-address} (Optional) Diagnoses basic network connectivity on AppleTalk,
Connectionless Network Service (CLNS), IP, Novell, Apollo, VINES,
DECnet, or Xerox Network System (XNS) networks.
Example:
•
Router# ping ip 10.0.0.1
Step 3 trace [protocol] [destination]
Example:
(Optional) Discovers the routes that packets will actually take when
traveling to their destination.
•
Router# trace ip 10.0.0.1
Step 4 show mpls forwarding-table [network
{mask | length} | labels label [-label] |
interface interface | next-hop address | lsptunnel [tunnel-id]] [vrf vrf-name] [detail]
Use the ping ip command to verify the connectivity from one CSC
core router to another.
Use the trace command to verify the path that a packet goes through
before reaching the final destination. The trace command can help
isolate a trouble spot if two routers cannot communicate.
(Optional) Displays the contents of the MPLS label forwarding
information base (LFIB).
•
Use the show mpls forwarding-table command to verify that
MPLS packets are being forwarded.
Example:
Router# show mpls forwarding-table
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Troubleshooting Tips
Command or Action
Purpose
Step 5 show mpls ldp discovery [vrf vrf-name | all] (Optional) Displays the status of the LDP discovery process.
•
Example:
Use the show mpls ldp discovery command to verify that LDP is
operational in the CSC core.
Router# show mpls ldp discovery
Step 6 show mpls ldp neighbor [[vrf vrf-name]
[address | interface] [detail] | all]
(Optional) Displays the status of LDP sessions.
•
Use theshow mpls ldp neighbor command to verify LDP
configuration in the CSC core.
Example:
Router# show mpls ldp neighbor
Step 7 show ip cef [vrf vrf-name] [network [mask]]
[longer-prefixes] [detail]
(Optional) Displays entries in the forwarding Information Base (FIB).
•
Use the show ip cef command to check the forwarding table
(prefixes, next hops, and interfaces).
Example:
Router# show ip cef
Step 8 show mpls interfaces [[vrf vrf-name]
[interface] [detail] |all]
(Optional) Displays information about one or more or all interfaces that
are configured for label switching.
•
Example:
Use theshow mpls interfaces command to verify that the interfaces
are configured to use LDP.
Router# show mpls interfaces
Step 9 show ip route
(Optional) Displays IP routing table entries.
•
Example:
Use the show ip route command to display the entire routing table,
including host IP address, next hop, and interface.
Router# show ip route
Step 10 disable
(Optional) Returns to privileged EXEC mode.
Example:
Router# disable
•
Troubleshooting Tips, page 63
Troubleshooting Tips
You can use the ping and trace commands to verify complete MPLS connectivity in the core. You also get
useful troubleshooting information from the additional show commands.
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Configuring VRFs for CSC-PE Routers
Configuring VRFs for CSC-PE Routers
Perform this task to configure VPN routing and forwarding (VRF) instances for the backbone carrier edge
(CSC-PE) routers.
SUMMARY STEPS
1. enable
2. configure terminal
3. ip vrf vrf-name
4. rd route-distinguisher
5. route-target {import | export | both} route-target-ext-community
6. import map route-map
7. exit
8. interface type number
9. ip vrf forwarding vrf-name
10. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 ip vrf vrf-name
Example:
Defines the VPN routing instance by assigning a VRF name and enters VRF
configuration mode.
•
The vrf-name argument is the name assigned to a VRF.
Router(config)# ip vrf vpn1
Step 4 rd route-distinguisher
Creates routing and forwarding tables.
•
Example:
Router(config-vrf)# rd 100:1
The route-distinguisher argument adds an 8-byte value to an IPv4 prefix
to create a VPN-IPv4 prefix. You can enter an RD in either of these
formats:
◦
◦
16-bit AS number: your 32-bit number, for example, 101:3
32-bit IP address: your 16-bit number, for example, 192.168.122.15:1
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Configuring VRFs for CSC-PE Routers
Command or Action
Step 5 route-target {import | export | both}
route-target-ext-community
Purpose
Creates a route-target extended community for a VRF.
•
Example:
•
Router(config-vrf)# route-target
import 100:1
•
•
Step 6 import map route-map
The import keyword imports routing information from the target VPN
extended community.
The export keyword exports routing information to the target VPN
extended community.
The both keyword imports routing information from and exports routing
information to the target VPN extended community.
The route-target-ext-community argument adds the route-target extended
community attributes to the VRF’s list of import, export, or both (import
and export) route-target extended communities.
(Optional) Configures an import route map for a VRF.
•
Example:
The route-map argument specifies the route map to be used as an import
route map for the VRF.
Router(config-vrf)# import map
vpn1-route-map
Step 7 exit
(Optional) Exits to global configuration mode.
Example:
Router(config-vrf)# exit
Step 8 interface type number
Specifies the interface to configure and enters interface configuration mode.
•
•
Example:
The type argument specifies the type of interface to be configured.
The number argument specifies the port, connector, or interface card
number.
Router(config)# interface
Ethernet5/0
Step 9 ip vrf forwarding vrf-name
Associates a VRF with the specified interface or subinterface.
•
The vrf-name argument is the name assigned to a VRF.
Example:
Router(config-if)# ip vrf
forwarding vpn1
Step 10 end
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-if)# end
•
Troubleshooting Tips, page 66
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Troubleshooting Tips
Troubleshooting Tips
Enter a show ip vrf detail command and make sure the MPLS VPN is up and associated with the right
interfaces.
Configuring Multiprotocol BGP for VPN Connectivity in the Backbone Carrier
Perform this task to configure Multiprotocol BGP (MP-BGP) connectivity in the backbone carrier.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. no bgp default ipv4-unicast
5. neighbor {ip-address | peer-group-name} remote-as as-number
6. neighbor {ip-address | peer-group-name} update-source interface-type
7. address-family vpnv4 [unicast]
8. neighbor {ip-address | peer-group-name} send-community extended
9. neighbor {ip-address | peer-group-name} activate
10. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Configures a BGP routing process and enters router configuration mode.
•
Example:
Router(config)# router bgp 100
The as-number argument indicates the number of an autonomous
system that identifies the router to other BGP routers and tags the
routing information passed along. Valid numbers are from 0 to
65535. Private autonomous system numbers that can be used in
internal networks range from 64512 to 65535.
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Configuring Multiprotocol BGP for VPN Connectivity in the Backbone Carrier
Command or Action
Purpose
Step 4 no bgp default ipv4-unicast
(Optional) Disables the IPv4 unicast address family on all neighbors.
•
Example:
Use the no bgp default-unicast command if you are using this
neighbor for MPLS routes only.
Router(config-router)# no bgp
default ipv4-unicast
Step 5 neighbor {ip-address | peer-group-name}
remote-as as-number
Example:
Adds an entry to the BGP or multiprotocol BGP neighbor table.
•
•
•
Router(config-router)# neighbor
10.5.5.5 remote-as 100
Step 6 neighbor {ip-address | peer-group-name}
update-source interface-type
Allows BGP sessions to use a specific operational interface for TCP
connections.
•
Example:
•
Router(config-router)# neighbor
10.2.0.0 update-source loopback0
•
Step 7 address-family vpnv4 [unicast]
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
The as-number argument specifies the autonomous system to which
the neighbor belongs.
The ip-address argument specifies the IP address of the BGPspeaking neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
The interface-type argument specifies the interface to be used as the
source.
Enters address family configuration mode for configuring routing
sessions, such as BGP, that use standard VPNv4 address prefixes.
•
Example:
The optional unicast keyword specifies VPNv4 unicast address
prefixes.
Router(config-router)# addressfamily vpnv4
Step 8 neighbor {ip-address | peer-group-name}
send-community extended
Specifies that a communities attribute should be sent to a BGP neighbor.
•
•
Example:
The ip-address argument specifies the IP address of the BGPspeaking neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
Router(config-router-af)# neighbor
10.0.0.1 send-community extended
Step 9 neighbor {ip-address | peer-group-name}
activate
Example:
Enables the exchange of information with a neighboring BGP router.
•
•
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
Router(config-router-af)# neighbor
10.4.0.0 activate
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Troubleshooting Tips
Command or Action
Step 10 end
Purpose
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-router-af)# end
•
•
Troubleshooting Tips, page 13
Troubleshooting Tips, page 68
Troubleshooting Tips
You can enter a show ip bgp neighbor command to verify that the neighbors are up and running. If this
command generates an error message, enter a debug ip bgp x.x.x.x events command, where x.x.x.x is the IP
address of the neighbor.
Configuring the CSC-PE and CSC-CE Routers
To enable the CSC-PE and CSC-CE routers to distribute routes and MPLS labels, perform the following
tasks:
•
•
•
Prerequisites, page 68
Configuring LDP on the CSC-PE and CSC-CE Routers, page 68
Enabling MPLS Encapsulation on the CSC-PE and CSC-CE Routers, page 70
Prerequisites
Before you configure the CSC-PE and CSC-CE routers, you must configure an IGP on the CSC-PE and
CSC-CE routers. A routing protocol is required between the PE and CE routers that connect the backbone
carrier to the customer carrier. The routing protocol enables the customer carrier to exchange IGP routing
information with the backbone carrier. Use the same routing protocol that the customer carrier uses. You
can choose RIP, OSPF, or static routing as the routing protocol. BGP is not supported. For the
configuration steps, see Configuring MPLS Layer 3 VPNs .
Configuring LDP on the CSC-PE and CSC-CE Routers
MPLS LDP is required between the PE and CE routers that connect the backbone carrier to the customer
carrier. You can configure LDP as the default label distribution protocol for the entire router or just for the
PE-to-CE interface for VRF.
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Configuring LDP on the CSC-PE and CSC-CE Routers
SUMMARY STEPS
1. enable
2. configure terminal
3. mpls label protocol ldp
4. interface type number
5. mpls label protocol ldp
6. exit
DETAILED STEPS
Command or Action
Purpose
Step 1 enable
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 mpls label protocol ldp
Specifies MPLS LDP as the default label distribution protocol for the
router.
Example:
Router(config)# mpls label protocol ldp
Step 4 interface type number
(Optional) Specifies the interface to configure and enters interface
configuration mode.
Example:
•
Router(config)# interface Ethernet5/0
•
Step 5 mpls label protocol ldp
The type argument specifies the type of interface to be
configured.
The number argument specifies the port, connector, or interface
card number.
(Optional) Specifies MPLS LDP as the default label distribution
protocol for the interface.
Example:
Router(config-if)# mpls label protocol ldp
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Enabling MPLS Encapsulation on the CSC-PE and CSC-CE Routers
Command or Action
Purpose
Step 6 exit
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-if)# exit
Enabling MPLS Encapsulation on the CSC-PE and CSC-CE Routers
Every packet that crosses the backbone carrier must be encapsulated, so that the packet includes MPLS
labels. You can enable MPLS encapsulation for the entire router or just on the interface of the PE or CE
router. To enable the encapsulation of packets, perform the following task.
SUMMARY STEPS
1. enable
2. configure terminal
3. mpls ip
4. interface type number
5. mpls ip
6. exit
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 mpls ip
Enables MPLS encapsulation for the router.
Example:
Router(config)# mpls ip
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Enabling MPLS Encapsulation on the CSC-PE and CSC-CE Routers
Command or Action
Purpose
Step 4 interface type number
(Optional) Specifies the interface to configure and enters interface
configuration mode.
•
•
Example:
Router(config)# interface Ethernet5/0
Step 5 mpls ip
The type argument specifies the type of interface to be configured.
The number argument specifies the port, connector, or interface card
number.
(Optional) Enables MPLS encapsulation for the specified interface.
Example:
Router(config-if)# mpls ip
Step 6 exit
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-if)# exit
Verifying the Carrier Supporting Carrier Configuration
The following commands verify the status of LDP sessions that were configured between the backbone
carrier and customer carrier. Now the customer carrier ISP sites appear as a VPN customer to the backbone
carrier.
SUMMARY STEPS
1. show mpls ldp discovery vrf vrf-name
2. show mpls ldp discovery all
DETAILED STEPS
Step 1
show mpls ldp discovery vrf vrf-name
Use this command to show that the LDP sessions are in VRF VPN1 of the PE router of the backbone carrier, for
example:
Example:
Router# show mpls ldp discovery vrf vpn1
Local LDP Identifier:
10.0.0.0:0
Discovery Sources:
Interfaces:
Ethernet1/0 (ldp): xmit/recv
LDP Id: 10.0.0.1:0
POS6/0 (ldp): xmit
Step 2
show mpls ldp discovery all
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Configuration Examples for MPLS VPN CSC with LDP and IGP
Use this command to list all LDP sessions in a router, for example:
Example:
Router# show mpls ldp discovery all
Local LDP Identifier:
10.10.10.10:0
Discovery Sources:
Interfaces:
Ethernet1/5 (ldp): xmit/recv
LDP Id: 10.5.5.5:0
VRF vpn1: Local LDP Identifier:
10.0.0.1:0
Discovery Sources:
Interfaces:
Ethernet1/0 (ldp): xmit/recv
LDP Id: 10.0.0.1:0
POS6/0 (ldp): xmit
The Local LDP Identifier field shows the LDP identifier for the local label switching router for this session. The
Interfaces field displays the interfaces engaging in LDP discovery activity:
•
•
xmit indicates that the interface is transmitting LDP discovery hello packets.
recv indicates that the interface is receiving LDP discovery hello packets.
Configuration Examples for MPLS VPN CSC with LDP and IGP
• MPLS VPN CSC Network with a Customer Who Is an ISP Example, page 72
• MPLS VPN CSC Network with a Customer Who Is an MPLS VPN Provider Example, page 77
• MPLS VPN CSC Network That Contains Route Reflectors Example, page 85
• MPLS VPN CSC Network with a Customer Who Has VPNs at the Network Edge Example, page
101
MPLS VPN CSC Network with a Customer Who Is an ISP Example
The figure below shows a carrier supporting carrier network configuration where the customer carrier is an
ISP. The customer carrier has two sites, each of which is a POP. The customer carrier connects these sites
using a VPN service provided by the backbone carrier. The backbone carrier uses MPLS. The ISP sites use
IP. To enable packet transfer between the ISP sites and the backbone carrier, the CE routers that connect
the ISPs to the backbone carrier run MPLS.
Figure 10
Carrier Supporting Carrier Network with a Customer Carrier Who Is an ISP
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CSC-CE1 Configuration
The following examples show the configuration of each router in the carrier supporting carrier network.
OSPF is used to connect the customer carrier to the backbone carrier.
•
•
•
•
CSC-CE1 Configuration,
CSC-PE1 Configuration,
CSC-PE2 Configuration,
CSC-CE2 Configuration,
page 73
page 73
page 75
page 76
CSC-CE1 Configuration
mpls label protocol ldp
!
interface Loopback0
ip address 10.14.14.14 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface ATM1/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 101 0 51 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
interface ATM2/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM2/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
router ospf 200
log-adjacency-changes
redistribute connected subnets
network 10.14.14.14 0.0.0.0 area 200
network 10.15.0.0 0.255.255.255 area 200
network 10.16.0.0 0.255.255.255 area 200
CSC-PE1 Configuration
ip cef distributed
!
ip vrf vpn1
rd 100:0
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route-target export 100:0
route-target import 100:0
mpls label protocol ldp
no mpls aggregate-statistics
!
interface Loopback0
ip address 10.11.11.11 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface Loopback100
ip vrf forwarding vpn1
ip address 10.19.19.19 255.255.255.255
no ip directed-broadcast
!
interface ATM1/1/0
no ip address
no ip directed-broadcast
no ip route-cache distributed
atm clock INTERNAL
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM1/1/0.1
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
interface ATM3/0/0
no ip address
no ip directed-broadcast
no ip route-cache distributed
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM3/0/0.1 point-to-point
ip vrf forwarding vpn1
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
atm pvc 101 0 51 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
router ospf 100
log-adjacency-changes
passive-interface ATM3/0/0.1
passive-interface Loopback100
network 10.11.11.11 0.0.0.0 area 100
network 10.0.0.0 0.255.255.255 area 100
!
router ospf 200 vrf vpn1
log-adjacency-changes
redistribute bgp 100 metric-type 1 subnets
network 10.19.19.19 0.0.0.0 area 200
network 10.0.0.0 0.255.255.255 area 200
!
router bgp 100
bgp log-neighbor-changes
timers bgp 10 30
neighbor 10.12.12.12 remote-as 100
neighbor 10.12.12.12 update-source Loopback0
!
address-family ipv4
neighbor 10.12.12.12 activate
neighbor 10.12.12.12 send-community extended
no synchronization
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exit-address-family
!
address-family vpnv4
neighbor 10.12.12.12 activate
neighbor 10.12.12.12 send-community extended
exit-address-family
!
address-family ipv4 vrf vpn1
redistribute ospf 200 match internal external 1 external 2
no auto-summary
no synchronization
exit-address-family
CSC-PE2 Configuration
ip cef distributed
!
ip vrf vpn1
rd 100:0
route-target export 100:0
route-target import 100:0
mpls label protocol ldp
no mpls aggregate-statistics
!
interface Loopback0
ip address 10.12.12.12 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface Loopback100
ip vrf forwarding vpn1
ip address 10.20.20.20 255.255.255.255
no ip directed-broadcast
!
interface ATM0/1/0
no ip address
no ip directed-broadcast
no ip route-cache distributed
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM0/1/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
interface ATM3/0/0
no ip address
no ip directed-broadcast
no ip route-cache distributed
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM3/0/0.1 point-to-point
ip vrf forwarding vpn1
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
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!
router ospf 100
log-adjacency-changes
passive-interface ATM3/0/0.1
passive-interface Loopback100
network 10.12.12.12 0.0.0.0 area 100
network 10.0.0.0 0.255.255.255 area 100
!
router ospf 200 vrf vpn1
log-adjacency-changes
redistribute bgp 100 metric-type 1 subnets
network 10.20.20.20 0.0.0.0 area 200
network 10.0.0.0 0.255.255.255 area 200
!
router bgp 100
bgp log-neighbor-changes
timers bgp 10 30
neighbor 10.11.11.11 remote-as 100
neighbor 10.11.11.11 update-source Loopback0
!
address-family ipv4
neighbor 10.11.11.11 activate
neighbor 10.11.11.11 send-community extended
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.11.11.11 activate
neighbor 10.11.11.11 send-community extended
exit-address-family
!
address-family ipv4 vrf vpn1
redistribute ospf 200 match internal external 1 external 2
no auto-summary
no synchronization
exit-address-family
CSC-CE2 Configuration
ip cef
!
mpls label protocol ldp
!
interface Loopback0
ip address 10.16.16.16 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface ATM1/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
interface ATM5/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
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CE1 Configuration
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM5/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
router ospf 200
log-adjacency-changes
redistribute connected subnets
network 10.16.16.16 0.0.0.0 area 200
network 10.0.0.0 0.255.255.255 area 200
network 10.0.0.0 0.255.255.255 area 200
MPLS VPN CSC Network with a Customer Who Is an MPLS VPN Provider
Example
The figure below shows a carrier supporting carrier network configuration where the customer carrier is an
MPLS VPN provider. The customer carrier has two sites. The backbone carrier and the customer carrier
use MPLS. The IBGP sessions exchange the external routing information of the ISP.
Figure 11
Carrier Supporting Carrier Network with a Customer Carrier Who Is an MPLS VPN Provider
The following configuration examples show the configuration of each router in the carrier supporting
carrier network. OSPF is the protocol used to connect the customer carrier to the backbone carrier.
•
•
•
•
•
•
•
•
CE1 Configuration, page 77
PE1 Configuration, page 78
CSC-CE1 Configuration, page 79
CSC-PE1 Configuration, page 80
CSC-PE2 Configuration, page 81
CSC-CE2 Configuration, page 82
PE2 Configuration, page 83
CE2 Configuration, page 84
CE1 Configuration
ip cef
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!
interface Loopback0
ip address 10.17.17.17 255.255.255.255
no ip directed-broadcast
!
interface Ethernet0/1
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
!
router ospf 300
log-adjacency-changes
redistribute bgp 300 subnets
passive-interface Ethernet0/1
network 10.17.17.17 0.0.0.0 area 300
!
router bgp 300
no synchronization
bgp log-neighbor-changes
timers bgp 10 30
redistribute connected
redistribute ospf 300 match internal external 1 external 2
neighbor 10.0.0.1 remote-as 200
neighbor 10.0.0.1 advertisement-interval 5
no auto-summary
PE1 Configuration
ip cef
!
ip vrf vpn2
rd 200:1
route-target export 200:1
route-target import 200:1
mpls label protocol ldp
!
interface Loopback0
ip address 10.13.13.13 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface ATM1/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
interface Ethernet3/0
ip vrf forwarding vpn2
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
!
router ospf 200
log-adjacency-changes
redistribute connected subnets
passive-interface Ethernet3/0
network 10.13.13.13 0.0.0.0 area 200
network 10.0.0.0 0.255.255.255 area 200
!
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router bgp 200
no bgp default ipv4-unicast
bgp log-neighbor-changes
timers bgp 10 30
neighbor 10.15.15.15 remote-as 200
neighbor 10.15.15.15 update-source Loopback0
!
address-family ipv4
neighbor 10.15.15.15 activate
neighbor 10.15.15.15 send-community extended
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.15.15.15 activate
neighbor 10.15.15.15 send-community extended
exit-address-family
!
address-family ipv4 vrf vpn2
neighbor 10.0.0.2 remote-as 300
neighbor 10.0.0.2 activate
neighbor 10.0.0.2 as-override
neighbor 10.0.0.2 advertisement-interval 5
no auto-summary
no synchronization
exit-address-family
CSC-CE1 Configuration
mpls label protocol ldp
!
interface Loopback0
ip address 10.14.14.14 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface ATM1/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 101 0 51 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
interface ATM2/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM2/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
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router ospf 200
log-adjacency-changes
redistribute connected subnets
network 10.14.14.14 0.0.0.0 area 200
network 10.0.0.0 0.255.255.255 area 200
network 10.0.0.0 0.255.255.255 area 200
CSC-PE1 Configuration
ip cef distributed
!
ip vrf vpn1
rd 100:0
route-target export 100:0
route-target import 100:0
mpls label protocol ldp
no mpls aggregate-statistics
!
interface Loopback0
ip address 11.11.11.11 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface Loopback100
ip vrf forwarding vpn1
ip address 10.19.19.19 255.255.255.255
no ip directed-broadcast
!
interface ATM1/1/0
no ip address
no ip directed-broadcast
no ip route-cache distributed
atm clock INTERNAL
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM1/1/0.1 point-to-point
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
interface ATM3/0/0
no ip address
no ip directed-broadcast
no ip route-cache distributed
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM3/0/0.1 point-to-point
ip vrf forwarding vpn1
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
atm pvc 101 0 51 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
router ospf 100
log-adjacency-changes
passive-interface ATM3/0/0.1
passive-interface Loopback100
network 10.11.11.11 0.0.0.0 area 100
network 10.0.0.0 0.255.255.255 area 100
!
router ospf 200 vrf vpn1
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log-adjacency-changes
redistribute bgp 100 metric-type 1 subnets
network 10.19.19.19 0.0.0.0 area 200
network 10.0.0.0 0.255.255.255 area 200
!
router bgp 100
bgp log-neighbor-changes
timers bgp 10 30
neighbor 10.12.12.12 remote-as 100
neighbor 10.12.12.12 update-source Loopback0
!
address-family ipv4
neighbor 10.12.12.12 activate
neighbor 10.12.12.12 send-community extended
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.12.12.12 activate
neighbor 10.12.12.12 send-community extended
exit-address-family
!
address-family ipv4 vrf vpn1
redistribute ospf 200 match internal external 1 external 2
no auto-summary
no synchronization
exit-address-family
CSC-PE2 Configuration
ip cef distributed
!
ip vrf vpn1
rd 100:0
route-target export 100:0
route-target import 100:0
mpls label protocol ldp
no mpls aggregate-statistics
!
interface Loopback0
ip address 10.12.12.12 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface Loopback100
ip vrf forwarding vpn1
ip address 10.20.20.20 255.255.255.255
no ip directed-broadcast
!
interface ATM0/1/0
no ip address
no ip directed-broadcast
no ip route-cache distributed
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM0/1/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
interface ATM3/0/0
no ip address
no ip directed-broadcast
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no ip route-cache distributed
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM3/0/0.1 point-to-point
ip vrf forwarding vpn1
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
router ospf 100
log-adjacency-changes
passive-interface ATM3/0/0.1
passive-interface Loopback100
network 10.12.12.12 0.0.0.0 area 100
network 10.0.0.0 0.255.255.255 area 100
!
router ospf 200 vrf vpn1
log-adjacency-changes
redistribute bgp 100 metric-type 1 subnets
network 10.20.20.20 0.0.0.0 area 200
network 10.0.0.0 0.255.255.255 area 200
!
router bgp 100
bgp log-neighbor-changes
timers bgp 10 30
neighbor 10.11.11.11 remote-as 100
neighbor 10.11.11.11 update-source Loopback0
!
address-family ipv4
neighbor 10.11.11.11 activate
neighbor 10.11.11.11 send-community extended
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.11.11.11 activate
neighbor 10.11.11.11 send-community extended
exit-address-family
!
address-family ipv4 vrf vpn1
redistribute ospf 200 match internal external 1 external 2
no auto-summary
no synchronization
exit-address-family
CSC-CE2 Configuration
ip cef
!
mpls label protocol ldp
!
interface Loopback0
ip address 10.16.16.16 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface ATM1/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
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no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
interface ATM5/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM5/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
router ospf 200
log-adjacency-changes
redistribute connected subnets
network 10.16.16.16 0.0.0.0 area 200
network 10.0.0.0 0.255.255.255 area 200
network 10.0.0.0 0.255.255.255 area 200
PE2 Configuration
ip cef
ip cef accounting non-recursive
!
ip vrf vpn2
rd 200:1
route-target export 200:1
route-target import 200:1
mpls label protocol ldp
!
interface Loopback0
ip address 10.15.15.15 255.255.255.255
no ip directed-broadcast
!
interface Ethernet3/0
ip vrf forwarding vpn2
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
!
interface ATM5/0
no ip address
no ip directed-broadcast
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM5/0.1 point-to-point
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
router ospf 200
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log-adjacency-changes
redistribute connected subnets
passive-interface Ethernet3/0
network 10.15.15.15 0.0.0.0 area 200
network 10.0.0.0 0.255.255.255 area 200
!
router bgp 200
no bgp default ipv4-unicast
bgp log-neighbor-changes
timers bgp 10 30
neighbor 10.13.13.13 remote-as 200
neighbor 10.13.13.13 update-source Loopback0
!
address-family ipv4
neighbor 10.13.13.13 activate
neighbor 10.13.13.13 send-community extended
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.13.13.13 activate
neighbor 10.13.13.13 send-community extended
exit-address-family
!
address-family ipv4 vrf vpn2
neighbor 10.0.0.2 remote-as 300
neighbor 10.0.0.2 activate
neighbor 10.0.0.2 as-override
neighbor 10.0.0.2 advertisement-interval 5
no auto-summary
no synchronization
exit-address-family
CE2 Configuration
ip cef
!
interface Loopback0
ip address 10.18.18.18 255.255.255.255
no ip directed-broadcast
!
interface Ethernet0/1
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
!
router ospf 300
log-adjacency-changes
redistribute bgp 300 subnets
passive-interface Ethernet0/1
network 10.18.18.18 0.0.0.0 area 300
!
router bgp 300
no synchronization
bgp log-neighbor-changes
timers bgp 10 30
redistribute connected
redistribute ospf 300 match internal external 1 external 2
neighbor 10.0.0.1 remote-as 200
neighbor 10.0.0.1 advertisement-interval 5
no auto-summary
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MPLS VPN CSC Network That Contains Route Reflectors Example
CE2 Configuration
MPLS VPN CSC Network That Contains Route Reflectors Example
The figure below shows a carrier supporting carrier network configuration that contains route reflectors.
The customer carrier has two sites.
Figure 12
Note
Carrier Supporting Carrier Network that Contains Route Reflectors
A connection between route reflectors (RRs) is not necessary.
The following configuration examples show the configuration of each router in the carrier supporting
carrier network. Note the following:
•
•
The router IP addresses are abbreviated for ease of reading. For example, the loopback address for PE
1 is 25, which is equivalent to 10.25.25.25.
The following list shows the loopback addresses for the CSC-PE routers:
◦
◦
•
•
CSC-PE1 (75K-37-3): loopback 0 = 10.15.15.15, loopback 1 = 10.18.18.18
CSC-PE2 (75K-38-3): loopback 0 = 10.16.16.16, loopback 1 = 10.20.20.20
Backbone Carrier Configuration, page 86
Customer Carrier Site 1 Configuration, page 91
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Backbone Carrier Configuration
•
Customer Carrier Site 2 Configuration, page 95
Backbone Carrier Configuration
•
•
•
•
Route Reflector 1 (72K-37-1) Configuration, page 86
Route Reflector 2 (72K-38-1) Configuration, page 87
CSC-PE1 (75K-37-3) Configuration, page 88
CSC-PE2 (75K-38-3) Configuration, page 89
Route Reflector 1 (72K-37-1) Configuration
interface Loopback0
ip address 10.13.13.13 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface ATM1/0
no ip address
no ip directed-broadcast
atm clock INTERNAL
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM1/0.1 mpls
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
no atm enable-ilmi-trap
mpls label protocol ldp
mpls atm vpi 2-5
mpls ip
!
interface ATM1/1
no ip address
no ip directed-broadcast
atm clock INTERNAL
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM1/1.1 mpls
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
no atm enable-ilmi-trap
mpls label protocol ldp
mpls atm vpi 2-5
mpls ip
!
router ospf 100
auto-cost reference-bandwidth 10000
network 10.0.0.0 0.255.255.255 area 100
network 10.1.0.0 0.255.255.255 area 100
network 10.2.0.0 0.255.255.255 area 100
!
router bgp 100
no synchronization
no bgp default ipv4-unicast
bgp cluster-id 1
redistribute static
neighbor 10.15.15.15 remote-as 100
neighbor 10.15.15.15 update-source Loopback0
neighbor 10.16.16.16 remote-as 100
neighbor 10.16.16.16 update-source Loopback0
!
address-family ipv4 vrf vpn1
no auto-summary
no synchronization
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Route Reflector 2 (72K-38-1) Configuration
exit-address-family
!
address-family vpnv4
neighbor 10.15.15.15
neighbor 10.15.15.15
neighbor 10.15.15.15
neighbor 10.16.16.16
neighbor 10.16.16.16
neighbor 10.16.16.16
bgp scan-time import
exit-address-family
activate
route-reflector-client
send-community extended
activate
route-reflector-client
send-community extended
5
Route Reflector 2 (72K-38-1) Configuration
interface Loopback0
ip address 10.14.14.14 255.255.255.255
no ip directed-broadcast
no ip mroute-cache
!
interface ATM1/0
no ip address
no ip directed-broadcast
atm clock INTERNAL
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM1/0.1 mpls
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
no atm enable-ilmi-trap
mpls label protocol ldp
mpls atm vpi 2-5
mpls ip
!
interface ATM1/1
no ip address
no ip directed-broadcast
atm clock INTERNAL
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM1/1.1 mpls
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
no atm enable-ilmi-trap
mpls label protocol ldp
mpls atm vpi 2-5
mpls ip
!
router ospf 100
auto-cost reference-bandwidth 10000
network 10.0.0.0 0.255.255.255 area 100
network 10.1.0 0.255.255.255 area 100
network 10.2.0.0 0.255.255.255 area 100
!
router bgp 100
no synchronization
no bgp default ipv4-unicast
bgp cluster-id 1
redistribute static
neighbor 10.15.15.15 remote-as 100
neighbor 10.15.15.15 update-source Loopback0
neighbor 10.16.16.16 remote-as 100
neighbor 10.16.16.16 update-source Loopback0
!
address-family ipv4 vrf vpn1
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.15.15.15 activate
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CSC-PE1 (75K-37-3) Configuration
neighbor 10.15.15.15
neighbor 10.15.15.15
neighbor 10.16.16.16
neighbor 10.16.16.16
neighbor 10.16.16.16
bgp scan-time import
exit-address-family
route-reflector-client
send-community extended
activate
route-reflector-client
send-community extended
5
CSC-PE1 (75K-37-3) Configuration
ip cef distributed
!
ip vrf vpn1
rd 100:1
route-target export 100:1
route-target import 100:1
!
interface Loopback0
ip address 10.15.15.15 255.255.255.255
no ip directed-broadcast
!
interface Loopback1
ip vrf forwarding vpn1
ip address 10.18.18.18 255.255.255.255
no ip directed-broadcast
!
interface Ethernet0/0/1
ip vrf forwarding vpn1
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
no ip route-cache distributed
mpls label protocol ldp
mpls ip
!
interface ATM1/1/0
no ip address
no ip directed-broadcast
no ip route-cache distributed
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM1/1/0.1 mpls
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
no atm enable-ilmi-trap
mpls label protocol ldp
mpls atm vpi 2-5
mpls ip
!
interface ATM3/0/0
no ip address
no ip directed-broadcast
no ip route-cache distributed
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM3/0/0.1 point-to-point
ip vrf forwarding vpn1
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 100 6 32 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
interface ATM3/1/0
no ip address
no ip directed-broadcast
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CSC-PE2 (75K-38-3) Configuration
no ip route-cache distributed
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM3/1/0.1 mpls
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
no atm enable-ilmi-trap
mpls label protocol ldp
mpls atm vpi 2-5
mpls ip
!
router ospf 100
auto-cost reference-bandwidth 10000
network 10.0.0.0 0.255.255.255 area 100
network 10.1.0.0 0.255.255.255 area 100
network 10.2.0.0 0.255.255.255 area 100
network 10.3.0.0 0.255.255.255 area 100
network 10.4.0.0 0.255.255.255 area 100
!
router ospf 1 vrf vpn1
redistribute bgp 100 metric-type 1 subnets
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
!
router bgp 100
no bgp default ipv4-unicast
bgp log-neighbor-changes
neighbor 10.13.13.13 remote-as 100
neighbor 10.13.13.13 update-source Loopback0
neighbor 10.14.14.14 remote-as 100
neighbor 10.14.14.14 update-source Loopback0
!
address-family ipv4
redistribute static
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.13.13.13 activate
neighbor 10.13.13.13 send-community extended
neighbor 10.14.14.14 activate
neighbor 10.14.14.14 send-community extended
exit-address-family
!
address-family ipv4 vrf vpn1
redistribute ospf 1 match internal external 1 external 2
no auto-summary
no synchronization
exit-address-family
CSC-PE2 (75K-38-3) Configuration
ip cef distributed
!
ip vrf vpn1
rd 100:1
route-target export 100:1
route-target import 100:1
!
interface Loopback0
ip address 10.16.16.16 255.255.255.255
no ip directed-broadcast
!
interface Loopback1
ip vrf forwarding vpn1
ip address 10.20.20.20 255.255.255.255
no ip directed-broadcast
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CSC-PE2 (75K-38-3) Configuration
!
interface ATM0/1/0
no ip address
no ip directed-broadcast
no ip route-cache distributed
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM0/1/0.1 mpls
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
no atm enable-ilmi-trap
mpls label protocol ldp
mpls atm vpi 2-5
mpls ip
!
interface ATM2/1/0
no ip address
no ip directed-broadcast
no ip route-cache distributed
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM2/1/0.1 mpls
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
no atm enable-ilmi-trap
mpls label protocol ldp
mpls atm vpi 2-5
mpls ip
!
interface ATM3/0/0
no ip address
no ip directed-broadcast
no ip route-cache distributed
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM3/0/0.1 point-to-point
ip vrf forwarding vpn1
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
atm pvc 100 6 32 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
interface ATM3/1/0
no ip address
no ip directed-broadcast
no ip route-cache distributed
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM3/1/0.1 point-to-point
ip vrf forwarding vpn1
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
atm pvc 101 6 33 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls ip
!
router ospf 100
auto-cost reference-bandwidth 10000
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Customer Carrier Site 1 Configuration
network 10.0.0.0 0.255.255.255 area 100
network 10.0.0.0 0.255.255.255 area 100
network 10.0.0.0 0.255.255.255 area 100
network 10.0.0.0 0.255.255.255 area 100
network 10.0.0.0 0.255.255.255 area 100
!
router ospf 1 vrf vpn1
redistribute bgp 100 metric-type 1 subnets
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
!
router bgp 100
no bgp default ipv4-unicast
bgp log-neighbor-changes
neighbor 10.13.13.13 remote-as 100
neighbor 10.13.13.13 update-source Loopback0
neighbor 10.14.14.14 remote-as 100
neighbor 10.14.14.14 update-source Loopback0
!
address-family ipv4
redistribute static
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.13.13.13 activate
neighbor 10.13.13.13 send-community extended
neighbor 10.14.14.14 activate
neighbor 10.14.14.14 send-community extended
exit-address-family
!
address-family ipv4 vrf vpn1
redistribute ospf 1 match internal external 1 external 2
no auto-summary
no synchronization
exit-address-family
Customer Carrier Site 1 Configuration
•
•
•
•
•
PE1 (72K-36-8) Configuration, page 91
CSC-CE1 (72K-36-9) Configuration, page 92
PE2 (72K-36-7) Configuration, page 93
Route Reflector 3 (36K-38-4) Configuration, page 94
CE1 (36K-36-1) Configuration, page 95
PE1 (72K-36-8) Configuration
ip cef
!
ip vrf vpn2
rd 200:1
route-target export 200:1
route-target import 200:1
no mpls ip propagate-ttl
!
interface Loopback0
ip address 10.25.25.25 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface ATM1/0
no ip address
no ip directed-broadcast
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CSC-CE1 (72K-36-9) Configuration
no ip mroute-cache
atm clock INTERNAL
no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
mpls label protocol ldp
mpls ip
!
interface Ethernet3/0
ip vrf forwarding vpn2
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
!
interface Ethernet3/1
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
mpls label protocol ldp
mpls ip
!
interface Ethernet3/2
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
mpls label protocol ldp
mpls ip
!
router ospf 1
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
!
router bgp 200
neighbor 10.22.22.22 remote-as 200
neighbor 10.22.22.22 update-source Loopback0
neighbor 10.23.23.23 remote-as 200
neighbor 10.23.23.23 update-source Loopback0
!
address-family ipv4 vrf vpn2
redistribute connected
neighbor 10.0.0.2 remote-as 300
neighbor 10.0.0.2 activate
neighbor 10.0.0.2 as-override
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.22.22.22 activate
neighbor 10.22.22.22 send-community extended
neighbor 10.23.23.23 activate
neighbor 10.23.23.23 send-community extended
exit-address-family
CSC-CE1 (72K-36-9) Configuration
ip cef
no ip domain-lookup
!
interface Loopback0
ip address 10.11.11.11 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface ATM1/0
no ip address
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PE2 (72K-36-7) Configuration
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
atm pvc 100 6 32 aal5snap
mpls label protocol ldp
mpls ip
!
interface ATM2/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
no atm ilmi-keepalive
!
interface ATM2/0.1 point-to-point
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
mpls label protocol ldp
mpls ip
!
interface Ethernet3/0
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
mpls label protocol ldp
mpls ip
!
interface Ethernet3/1
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
mpls label protocol ldp
mpls ip
!
router ospf 1
network 10.0.0.0 0.255.255.255 area
network 10.0.0.0 0.255.255.255 area
network 10.0.0.0 0.255.255.255 area
network 10.0.0.0 0.255.255.255 area
network 10.0.0.0 0.255.255.255 area
101
101
101
101
101
PE2 (72K-36-7) Configuration
ip cef
!
ip vrf vpn2
rd 200:1
route-target export 200:1
route-target import 200:1
no mpls ip propagate-ttl
!
interface Loopback0
ip address 10.24.24.24 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface Ethernet3/0
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
mpls label protocol ldp
mpls ip
!
interface Ethernet3/1
ip vrf forwarding vpn2
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Route Reflector 3 (36K-38-4) Configuration
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
!
interface Ethernet3/2
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
mpls label protocol ldp
mpls ip
!
interface Ethernet3/3
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
mpls label protocol ldp
mpls ip
!
router ospf 1
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
!
router bgp 200
neighbor 10.22.22.22 remote-as 200
neighbor 10.22.22.22 update-source Loopback0
neighbor 10.23.23.23 remote-as 200
neighbor 10.23.23.23 update-source Loopback0
!
address-family ipv4 vrf vpn2
neighbor 10.0.0.2 remote-as 300
neighbor 10.0.0.2 activate
neighbor 10.0.0.2 as-override
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.22.22.22 activate
neighbor 10.22.22.22 send-community extended
neighbor 10.23.23.23 activate
neighbor 10.23.23.23 send-community extended
exit-address-family
Route Reflector 3 (36K-38-4) Configuration
ip cef
!
interface Loopback0
ip address 10.23.23.23 255.255.255.255
!
interface Ethernet1/1
ip address 10.0.0.1 255.0.0.0
mpls label protocol ldp
mpls ip
!
interface Ethernet1/2
ip address 10.0.0.1 255.0.0.0
mpls label protocol ldp
mpls ip
!
interface ATM3/0
no ip address
no ip mroute-cache
atm clock INTERNAL
no atm scrambling cell-payload
no atm ilmi-keepalive
!
interface ATM3/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
atm pvc 100 0 55 aal5snap
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CE1 (36K-36-1) Configuration
mpls label protocol ldp
mpls ip
!
router ospf 1
log-adjacency-changes
network 10.0.0.0 0.255.255.255 area 101
network 10.1.0.0 0.255.255.255 area 101
network 10.2.0.0 0.255.255.255 area 101
network 10.3.0.0 0.255.255.255 area 101
!
router bgp 200
no synchronization
no bgp default ipv4-unicast
bgp cluster-id 2
redistribute static
neighbor 10.21.21.21 remote-as 200
neighbor 10.21.21.21 update-source Loopback0
neighbor 10.24.24.24 remote-as 200
neighbor 10.24.24.24 update-source Loopback0
neighbor 10.25.25.25 remote-as 200
neighbor 10.25.25.25 update-source Loopback0
!
address-family ipv4 vrf vpn2
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.21.21.21 activate
neighbor 10.21.21.21 route-reflector-client
neighbor 10.21.21.21 send-community extended
neighbor 10.24.24.24 activate
neighbor 10.24.24.24 route-reflector-client
neighbor 10.24.24.24 send-community extended
neighbor 10.25.25.25 activate
neighbor 10.25.25.25 route-reflector-client
neighbor 10.25.25.25 send-community extended
exit-address-family
CE1 (36K-36-1) Configuration
ip cef
!
interface Loopback0
ip address 10.28.28.28 255.255.255.255
no ip directed-broadcast
!
interface Ethernet0/1
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
!
interface Ethernet0/2
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
!
router bgp 300
network 10.0.0.0
network 10.0.0.0
network 10.0.0.0
neighbor 10.0.0.1 remote-as 200
neighbor 10.0.0.1 remote-as 200
Customer Carrier Site 2 Configuration
•
•
•
•
CSC-CE3 (72K-36-6) Configuration, page 96
PE3 (72K-36-4) Configuration, page 96
CSC-CE4 (72K-36-5) Configuration, page 98
Route Reflector 4 (36K-38-5) Configuration, page 98
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CSC-CE3 (72K-36-6) Configuration
•
•
CE2 (36K-36-2) Configuration, page 99
CE3 (36K-36-3) Configuration, page 99
CSC-CE3 (72K-36-6) Configuration
ip cef
!
interface Loopback0
ip address 10.12.12.12 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface ATM1/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 100 6 32 aal5snap
mpls label protocol ldp
mpls ip
!
interface POS2/0
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
encapsulation ppp
mpls label protocol ldp
mpls ip
!
interface ATM5/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
no atm ilmi-keepalive
!
interface ATM5/0.1 point-to-point
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 40 aal5snap
mpls ip
!
router ospf 1
network 10.0.0.0 0.255.255.255 area 101
network 10.1.0.0 0.255.255.255 area 101
network 10.2.0.0 0.255.255.255 area 101
network 10.3.0.0 0.255.255.255 area 101
PE3 (72K-36-4) Configuration
ip cef
!
ip vrf vpn2
rd 200:1
route-target export 200:1
route-target import 200:1
!
!
interface Loopback0
ip address 10.21.21.21 255.255.255.255
no ip directed-broadcast
!
interface Ethernet3/0
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PE3 (72K-36-4) Configuration
ip vrf forwarding vpn2
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
!
interface Ethernet3/1
ip vrf forwarding vpn2
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
!
interface Ethernet3/2
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
mpls label protocol ldp
mpls ip
!
interface ATM5/0
no ip address
no ip directed-broadcast
atm clock INTERNAL
no atm ilmi-keepalive
!
interface ATM5/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 40 aal5snap
mpls label protocol ldp
mpls ip
!
interface ATM6/0
no ip address
no ip directed-broadcast
atm clock INTERNAL
no atm ilmi-keepalive
!
interface ATM6/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 20 aal5snap
mpls label protocol ldp
mpls ip
!
router ospf 1
network 10.0.0.0 0.255.255.255 area 101
network 10.1.0.0 0.255.255.255 area 101
network 10.2.0.0 0.255.255.255 area 101
network 10.3.0.0 0.255.255.255 area 101
!
router bgp 200
neighbor 10.22.22.22 remote-as 200
neighbor 10.22.22.22 update-source Loopback0
neighbor 10.23.23.23 remote-as 200
neighbor 10.23.23.23 update-source Loopback0
!
address-family ipv4 vrf vpn2
redistribute connected
neighbor 10.0.0.2 remote-as 300
neighbor 10.0.0.2 activate
neighbor 10.0.0.2 as-override
neighbor 10.0.0.2 remote-as 300
neighbor 10.0.0.2 activate
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.22.22.22 activate
neighbor 10.22.22.22 send-community extended
neighbor 10.23.23.23 activate
neighbor 10.23.23.23 send-community extended
exit-address-family
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MPLS VPN Carrier Supporting Carrier Using LDP and an IGP
CSC-CE4 (72K-36-5) Configuration
CSC-CE4 (72K-36-5) Configuration
ip cef
!
interface Loopback0
ip address 10.10.10.10 255.255.255.255
no ip directed-broadcast
!
interface POS4/0
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
encapsulation ppp
mpls label protocol ldp
mpls ip
clock source internal
!
interface ATM5/0
no ip address
no ip directed-broadcast
atm clock INTERNAL
no atm ilmi-keepalive
!
interface ATM5/0.1 point-to-point
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
atm pvc 100 0 20 aal5snap
mpls label protocol ldp
mpls ip
!
interface ATM6/0
no ip address
no ip directed-broadcast
atm clock INTERNAL
no atm ilmi-keepalive
!
interface ATM6/0.1 point-to-point
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
atm pvc 100 6 33 aal5snap
mpls label protocol ldp
mpls ip
!
router ospf 1
network 10.0.0.0 0.255.255.255 area 101
network 10.1.0.0 0.255.255.255 area 101
network 10.2.0.0 0.255.255.255 area 101
network 10.3.0.0 0.255.255.255 area 101
Route Reflector 4 (36K-38-5) Configuration
ip cef
!
interface Loopback0
ip address 10.22.22.22 255.255.255.255
!
interface Ethernet0/1
ip address 10.0.0.2 255.0.0.0
mpls label protocol ldp
mpls ip
!
interface ATM2/0
no ip address
no ip mroute-cache
atm clock INTERNAL
no atm scrambling cell-payload
no atm ilmi-keepalive
!
interface ATM2/0.1 point-to-point
ip address 10.0.0.1 255.0.0.0
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MPLS VPN Carrier Supporting Carrier Using LDP and an IGP
CE2 (36K-36-2) Configuration
atm pvc 100 0 55 aal5snap
mpls label protocol ldp
mpls ip
!
router ospf 1
log-adjacency-changes
network 10.0.0.0 0.255.255.255 area 101
network 10.1.0.0 0.255.255.255 area 101
network 10.2.0.0 0.255.255.255 area 101
!
router bgp 200
no synchronization
no bgp default ipv4-unicast
bgp cluster-id 2
redistribute static
neighbor 10.21.21.21 remote-as 200
neighbor 10.21.21.21 update-source Loopback0
neighbor 10.24.24.24 remote-as 200
neighbor 10.24.24.24 update-source Loopback0
neighbor 10.25.25.25 remote-as 200
neighbor 10.25.25.25 update-source Loopback0
!
address-family ipv4 vrf vpn2
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.21.21.21 activate
neighbor 10.21.21.21 route-reflector-client
neighbor 10.21.21.21 send-community extended
neighbor 10.24.24.24 activate
neighbor 10.24.24.24 route-reflector-client
neighbor 10.24.24.24 send-community extended
neighbor 10.25.25.25 activate
neighbor 10.25.25.25 route-reflector-client
neighbor 10.25.25.25 send-community extended
exit-address-family
CE2 (36K-36-2) Configuration
ip cef
!
interface Loopback0
ip address 10.26.26.26 255.255.255.255
no ip directed-broadcast
!
interface Ethernet0/1
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
!
interface Ethernet0/2
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
!
router ospf 300
redistribute bgp 300
network 10.0.0.0 0.255.255.255 area 300
network 10.0.0.0 0.255.255.255 area 300
!
router bgp 300
network 10.0.0.0
network 10.1.0.0
network 10.2.0.0
neighbor 10.0.0.1 remote-as 200
CE3 (36K-36-3) Configuration
ip cef
!
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CE3 (36K-36-3) Configuration
interface Loopback0
ip address 10.27.27.27 255.255.255.255
no ip directed-broadcast
!
interface Ethernet1/1
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
!
interface Ethernet1/2
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
!
router ospf 300
redistribute bgp 300
network 10.0.0.0 0.255.255.255 area 300
network 10.0.0.0 0.255.255.255 area 300
!
router bgp 300
network 10.0.0.0
network 10.1.0.0
network 10.2.0.0
neighbor 10.0.0.1 remote-as 200
MPLS Layer 3 VPNs Inter-AS and CSC Configuration Guide, Cisco IOS Release 12.4T
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MPLS VPN CSC Network with a Customer Who Has VPNs at the Network Edge Example
Backbone Carrier Configuration
MPLS VPN CSC Network with a Customer Who Has VPNs at the Network
Edge Example
The figure below shows a carrier supporting carrier network configuration where the customer carrier has
VPNs at the network edge.
Figure 13
•
•
•
Carrier Supporting Carrier Network
Backbone Carrier Configuration, page 101
Customer Carrier Site 1 Configuration, page 108
Customer Carrier Site 2 Configuration, page 110
Backbone Carrier Configuration
•
•
•
•
CSC-PE1 (72K-36-9) Configuration, page 102
P1 (75K-37-3) Configuration, page 103
P2 (75K-38-3) Configuration, page 105
CSC-PE2 (72K-36-5) Configuration, page 106
MPLS Layer 3 VPNs Inter-AS and CSC Configuration Guide, Cisco IOS Release 12.4T
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MPLS VPN Carrier Supporting Carrier Using LDP and an IGP
CSC-PE1 (72K-36-9) Configuration
CSC-PE1 (72K-36-9) Configuration
ip cef
!
ip vrf vpn1
rd 100:0
route-target export 100:0
route-target import 100:0
mpls label protocol ldp
!
!
interface Loopback0
ip address 10.14.14.14 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface Loopback100
ip vrf forwarding vpn1
ip address 10.22.22.22 255.255.255.255
no ip directed-broadcast
!
interface ATM1/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
ip address 10.1.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM1/0.2 point-to-point
ip address 10.2.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 101 0 51 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM1/0.3 point-to-point
ip address 10.3.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 102 0 52 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM2/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM2/0.1 point-to-point
ip vrf forwarding vpn1
ip address 10.15.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
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MPLS VPN Carrier Supporting Carrier Using LDP and an IGP
P1 (75K-37-3) Configuration
interface ATM2/0.2 point-to-point
ip vrf forwarding vpn1
ip address 10.16.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 101 0 51 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM2/0.3 point-to-point
ip vrf forwarding vpn1
ip address 10.17.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 102 0 52 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
router ospf 100
log-adjacency-changes
redistribute connected subnets
passive-interface ATM2/0.1
passive-interface ATM2/0.2
passive-interface ATM2/0.3
passive-interface Loopback100
network 10.14.14.14 0.0.0.0 area 100
network 10.1.0.0 0.0.255.255 area 100
network 10.2.0.0 0.0.255.255 area 100
network 10.3.0.0 0.0.255.255 area 100
!
router ospf 200 vrf vpn1
log-adjacency-changes
redistribute connected subnets
redistribute bgp 100 metric-type 1 subnets
network 10.22.22.22 0.0.0.0 area 200
network 10.15.0.0 0.0.255.255 area 200
network 10.16.0.0 0.0.255.255 area 200
network 10.17.0.0 0.0.255.255 area 200
!
router bgp 100
bgp log-neighbor-changes
timers bgp 10 30
neighbor 10.11.11.11 remote-as 100
neighbor 10.11.11.11 update-source Loopback0
!
address-family ipv4
neighbor 10.11.11.11 activate
neighbor 10.11.11.11 send-community extended
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.11.11.11 activate
neighbor 10.11.11.11 send-community extended
exit-address-family
!
address-family ipv4 vrf vpn1
redistribute ospf 200 match internal external 1 external 2
no auto-summary
no synchronization
exit-address-family
P1 (75K-37-3) Configuration
ip cef distributed
!
mpls label protocol ldp
!
interface Loopback0
ip address 10.12.12.12 255.255.255.255
no ip directed-broadcast
no ip route-cache
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MPLS VPN Carrier Supporting Carrier Using LDP and an IGP
P1 (75K-37-3) Configuration
no ip mroute-cache
!
interface ATM1/1/0
no ip address
no ip directed-broadcast
ip route-cache distributed
atm clock INTERNAL
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM1/1/0.1 point-to-point
ip address 10.7.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 103 0 53 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM1/1/0.2 point-to-point
ip address 10.8.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 104 0 54 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM1/1/0.3 point-to-point
ip address 10.9.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 105 0 55 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM3/0/0
no ip address
no ip directed-broadcast
ip route-cache distributed
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM3/0/0.1 point-to-point
ip address 10.1.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
mpls accounting experimental input
tag-switching ip
!
interface ATM3/0/0.2 point-to-point
ip address 10.2.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 101 0 51 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM3/0/0.3 point-to-point
ip address 10.3.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 102 0 52 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
router ospf 100
log-adjacency-changes
redistribute connected subnets
network 10.12.12.12 0.0.0.0 area 100
network 10.1.0.0 0.0.255.255 area 100
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P2 (75K-38-3) Configuration
network
network
network
network
network
10.2.0.0
10.3.0.0
10.7.0.0
10.8.0.0
10.9.0.0
0.0.255.255
0.0.255.255
0.0.255.255
0.0.255.255
0.0.255.255
area
area
area
area
area
100
100
100
100
100
P2 (75K-38-3) Configuration
ip cef distributed
!
mpls label protocol ldp
!
interface Loopback0
ip address 10.13.13.13 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface ATM0/1/0
no ip address
no ip directed-broadcast
ip route-cache distributed
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM0/1/0.1 point-to-point
ip address 10.7.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 103 0 53 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM0/1/0.2 point-to-point
ip address 10.8.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 104 0 54 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM0/1/0.3 point-to-point
ip address 10.9.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 105 0 55 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM3/1/0
no ip address
no ip directed-broadcast
ip route-cache distributed
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM3/1/0.1 point-to-point
ip address 10.4.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM3/1/0.2 point-to-point
ip address 10.5.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 101 0 51 aal5snap
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MPLS VPN Carrier Supporting Carrier Using LDP and an IGP
CSC-PE2 (72K-36-5) Configuration
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM3/1/0.3 point-to-point
ip address 10.6.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 102 0 52 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
router ospf 100
log-adjacency-changes
redistribute connected subnets
network 10.13.13.13 0.0.0.0 area 100
network 10.4.0.0 0.0.255.255 area 100
network 10.5.0.0 0.0.255.255 area 100
network 10.6.0.0 0.0.255.255 area 100
network 10.7.0.0 0.0.255.255 area 100
network 10.8.0.0 0.0.255.255 area 100
network 10.9.0.0 0.0.255.255 area 100
!
CSC-PE2 (72K-36-5) Configuration
ip cef
!
ip vrf vpn1
rd 100:0
route-target export 100:0
route-target import 100:0
mpls label protocol ldp
!
interface Loopback0
ip address 10.11.11.11 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface Loopback100
ip vrf forwarding vpn1
ip address 10.23.23.23 255.255.255.255
no ip directed-broadcast
!
interface ATM5/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM5/0.1 point-to-point
ip vrf forwarding vpn1
ip address 10.18.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM5/0.2 point-to-point
ip vrf forwarding vpn1
ip address 10.19.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 101 0 51 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
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MPLS VPN Carrier Supporting Carrier Using LDP and an IGP
CSC-PE2 (72K-36-5) Configuration
interface ATM5/0.3 point-to-point
ip vrf forwarding vpn1
ip address 10.20.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 102 0 52 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM6/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM6/0.1 point-to-point
ip address 10.4.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM6/0.2 point-to-point
ip address 10.5.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 101 0 51 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM6/0.3 point-to-point
ip address 10.6.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 102 0 52 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
router ospf 100
log-adjacency-changes
redistribute connected subnets
passive-interface ATM5/0.1
passive-interface ATM5/0.2
passive-interface ATM5/0.3
passive-interface Loopback100
network 10.11.11.11 0.0.0.0 area 100
network 10.4.0.0 0.0.255.255 area 100
network 10.5.0.0 0.0.255.255 area 100
network 10.6.0.0 0.0.255.255 area 100
!
router ospf 200 vrf vpn1
log-adjacency-changes
redistribute connected subnets
redistribute bgp 100 metric-type 1 subnets
network 10.23.23.23 0.0.0.0 area 200
network 10.18.0.0 0.0.255.255 area 200
network 10.19.0.0 0.0.255.255 area 200
network 10.20.0.0 0.0.255.255 area 200
!
router bgp 100
bgp log-neighbor-changes
timers bgp 10 30
neighbor 10.14.14.14 remote-as 100
neighbor 10.14.14.14 update-source Loopback0
!
address-family ipv4
neighbor 10.14.14.14 activate
neighbor 10.14.14.14 send-community extended
no synchronization
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MPLS VPN Carrier Supporting Carrier Using LDP and an IGP
Customer Carrier Site 1 Configuration
exit-address-family
!
address-family vpnv4
neighbor 10.14.14.14 activate
neighbor 10.14.14.14 send-community extended
exit-address-family
!
address-family ipv4 vrf vpn1
redistribute ospf 200 match internal external 1 external 2
no auto-summary
no synchronization
exit-address-family
Customer Carrier Site 1 Configuration
•
•
•
CSC-CE1 (72K-36-8) Configuration, page 108
PE2 (72K-36-7) Configuration, page 93
CE1 (36K-36-1) Configuration, page 110
CSC-CE1 (72K-36-8) Configuration
ip cef
!
mpls label protocol ldp
!
interface Loopback0
ip address 10.15.15.15 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface ATM1/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
ip address 10.15.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM1/0.2 point-to-point
ip address 10.16.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 101 0 51 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM1/0.3 point-to-point
ip address 10.17.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 102 0 52 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface Ethernet3/1
ip address 10.10.0.2 255.255.0.0
no ip directed-broadcast
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MPLS VPN Carrier Supporting Carrier Using LDP and an IGP
PE2 (72K-36-7) Configuration
no ip mroute-cache
mpls label protocol ldp
tag-switching ip
!
router ospf 200
log-adjacency-changes
redistribute connected subnets
network 10.15.15.15 0.0.0.0 area 200
network 10.10.0.0 0.0.255.255 area 200
network 10.15.0.0 0.0.255.255 area 200
network 10.16.0.0 0.0.255.255 area 200
network 10.17.0.0 0.0.255.255 area 200
PE2 (72K-36-7) Configuration
ip cef
!
ip vrf vpn2
rd 200:1
route-target export 200:1
route-target import 200:1
no mpls ip propagate-ttl
!
interface Loopback0
ip address 10.24.24.24 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface Ethernet3/0
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
mpls label protocol ldp
mpls ip
!
interface Ethernet3/1
ip vrf forwarding vpn2
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
!
interface Ethernet3/2
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
mpls label protocol ldp
mpls ip
!
interface Ethernet3/3
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
no ip mroute-cache
mpls label protocol ldp
mpls ip
!
router ospf 1
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
network 10.0.0.0 0.255.255.255 area 101
!
router bgp 200
neighbor 10.22.22.22 remote-as 200
neighbor 10.22.22.22 update-source Loopback0
neighbor 10.23.23.23 remote-as 200
neighbor 10.23.23.23 update-source Loopback0
!
address-family ipv4 vrf vpn2
neighbor 10.0.0.2 remote-as 300
neighbor 10.0.0.2 activate
neighbor 10.0.0.2 as-override
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CE1 (36K-36-1) Configuration
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.22.22.22
neighbor 10.22.22.22
neighbor 10.23.23.23
neighbor 10.23.23.23
exit-address-family
activate
send-community extended
activate
send-community extended
CE1 (36K-36-1) Configuration
ip cef
!
interface Loopback0
ip address 10.19.19.19 255.255.255.255
no ip directed-broadcast
!
interface Ethernet0/2
ip address 30.35.0.1 255.255.0.0
no ip directed-broadcast
!
router ospf 300
log-adjacency-changes
redistribute connected subnets
redistribute bgp 300 subnets
passive-interface Ethernet0/2
network 10.19.19.19 0.0.0.0 area 300
!
router bgp 300
no synchronization
bgp log-neighbor-changes
timers bgp 10 30
redistribute connected
redistribute ospf 300 match internal external 1 external 2
neighbor 10.35.0.2 remote-as 200
neighbor 10.35.0.2 advertisement-interval 5
no auto-summary
Customer Carrier Site 2 Configuration
•
•
•
•
CSC-CE2 (72K-36-4) Configuration, page 110
PE2 (72K-36-6) Configuration, page 111
CE2 (36K-38-4) Configuration, page 113
CE3 (36K-38-5) Configuration, page 113
CSC-CE2 (72K-36-4) Configuration
ip cef
!
mpls label protocol ldp
!
interface Loopback0
ip address 10.17.17.17 255.255.255.255
no ip directed-broadcast
!
interface ATM5/0
no ip address
no ip directed-broadcast
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
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PE2 (72K-36-6) Configuration
interface ATM5/0.1 point-to-point
ip address 10.11.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM5/0.2 point-to-point
ip address 10.12.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 101 0 51 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM5/0.3 point-to-point
ip address 10.13.0.2 255.255.0.0
no ip directed-broadcast
atm pvc 102 0 52 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM6/0
no ip address
no ip directed-broadcast
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM6/0.1 point-to-point
ip address 10.18.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM6/0.2 point-to-point
ip address 10.19.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 101 0 51 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM6/0.3 point-to-point
ip address 10.20.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 102 0 52 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
router ospf 200
log-adjacency-changes
redistribute connected subnets
network 10.17.17.17 0.0.0.0 area 200
network 10.11.0.0 0.0.255.255 area 200
network 10.12.0.0 0.0.255.255 area 200
network 10.13.0.0 0.0.255.255 area 200
network 10.18.0.0 0.0.255.255 area 200
network 10.19.0.0 0.0.255.255 area 200
network 10.20.0.0 0.0.255.255 area 200
PE2 (72K-36-6) Configuration
ip cef
!
ip vrf customersite
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PE2 (72K-36-6) Configuration
rd 200:1
route-target export 200:1
route-target import 200:1
mpls label protocol ldp
!
interface Loopback0
ip address 10.18.18.18 255.255.255.255
no ip directed-broadcast
no ip route-cache
no ip mroute-cache
!
interface Ethernet3/0
ip vrf forwarding customersite
ip address 10.29.0.2 255.255.0.0
no ip directed-broadcast
!
interface Ethernet3/1
ip vrf forwarding customersite
ip address 10.30.0.2 255.255.0.0
no ip directed-broadcast
!
interface ATM5/0
no ip address
no ip directed-broadcast
no ip mroute-cache
atm clock INTERNAL
atm sonet stm-1
no atm enable-ilmi-trap
no atm ilmi-keepalive
!
interface ATM5/0.1 point-to-point
ip address 10.11.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 100 0 50 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM5/0.2 point-to-point
ip address 10.12.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 101 0 51 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
interface ATM5/0.3 point-to-point
ip address 10.13.0.1 255.255.0.0
no ip directed-broadcast
atm pvc 102 0 52 aal5snap
no atm enable-ilmi-trap
mpls label protocol ldp
tag-switching ip
!
router ospf 200
log-adjacency-changes
redistribute connected subnets
passive-interface Ethernet3/0
passive-interface Ethernet3/1
network 10.18.18.18 0.0.0.0 area 200
network 10.11.0.0 0.0.255.255 area 200
network 10.12.0.0 0.0.255.255 area 200
network 10.13.0.0 0.0.255.255 area 200
!
router bgp 200
no bgp default ipv4-unicast
bgp log-neighbor-changes
timers bgp 10 30
neighbor 10.16.16.16 remote-as 200
neighbor 10.16.16.16 update-source Loopback0
!
address-family ipv4
neighbor 10.16.16.16 activate
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CE2 (36K-38-4) Configuration
neighbor 10.16.16.16 send-community extended
no synchronization
exit-address-family
!
address-family vpnv4
neighbor 10.16.16.16 activate
neighbor 10.16.16.16 send-community extended
exit-address-family
!
address-family ipv4 vrf customersite
neighbor 10.29.0.1 remote-as 300
neighbor 10.29.0.1 activate
neighbor 10.29.0.1 as-override
neighbor 10.29.0.1 advertisement-interval 5
neighbor 10.30.0.1 remote-as 300
neighbor 10.30.0.1 activate
neighbor 10.30.0.1 as-override
neighbor 10.30.0.1 advertisement-interval 5
no auto-summary
no synchronization
exit-address-family
CE2 (36K-38-4) Configuration
ip cef
!
interface Loopback0
ip address 10.21.21.21 255.255.255.255
!
interface Ethernet1/3
ip address 10.29.0.1 255.255.0.0
!
interface Ethernet5/0
ip address 10.14.0.1 255.255.0.0
!
router ospf 300
log-adjacency-changes
redistribute connected subnets
redistribute bgp 300 subnets
passive-interface Ethernet1/3
network 10.21.21.21 0.0.0.0 area 300
network 10.14.0.0 0.0.255.255 area 300
!
router bgp 300
no synchronization
timers bgp 10 30
redistribute connected
redistribute ospf 300 match internal external 1 external 2
neighbor 10.29.0.2 remote-as 200
neighbor 10.29.0.2 advertisement-interval 5
no auto-summary
CE3 (36K-38-5) Configuration
ip cef
!
interface Loopback0
ip address 10.20.20.20 255.255.255.255
no ip directed-broadcast
!
interface Ethernet0/2
ip address 10.30.0.1 255.255.0.0
no ip directed-broadcast
!
interface Ethernet0/3
ip address 10.14.0.2 255.255.0.0
no ip directed-broadcast
!
router ospf 300
log-adjacency-changes
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Additional References
redistribute connected subnets
redistribute bgp 300 subnets
passive-interface Ethernet0/2
network 10.20.20.20 0.0.0.0 area 300
network 10.14.0.0 0.0.255.255 area 300
!
router bgp 300
no synchronization
bgp log-neighbor-changes
timers bgp 10 30
redistribute connected
redistribute ospf 300 match internal external 1 external 2
neighbor 10.30.0.2 remote-as 200
neighbor 10.30.0.2 advertisement-interval 5
no auto-summary
Additional References
The following sections provide references related to MPLS VPNs.
Related Documents
Related Topic
Document Title
MPLS
MPLS Product Literature
Standards
Standard
Title
No new or modified standards are supported by this -feature, and support for existing standards has not
been modified by this feature.
MIBs
MIB
MIBs Link
No new or modified MIBs are supported by this
feature, and support for existing MIBs has not been
modified by this feature.
To locate and download MIBs for selected
platforms, Cisco software releases, and feature sets,
use Cisco MIB Locator found at the following
URL:
http://www.cisco.com/go/mibs
RFCs
RFC
Title
RFC 2547
BGP/MPLS VPNs
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MPLS VPN Carrier Supporting Carrier Using LDP and an IGP
Feature Information for MPLS VPN CSC with LDP and IGP
Technical Assistance
Description
Link
The Cisco Support website provides extensive
http://www.cisco.com/techsupport
online resources, including documentation and tools
for troubleshooting and resolving technical issues
with Cisco products and technologies.
To receive security and technical information about
your products, you can subscribe to various
services, such as the Product Alert Tool (accessed
from Field Notices), the Cisco Technical Services
Newsletter, and Really Simple Syndication (RSS)
Feeds.
Access to most tools on the Cisco Support website
requires a Cisco.com user ID and password.
Feature Information for MPLS VPN CSC with LDP and IGP
The following table provides release information about the feature or features described in this module.
This table lists only the software release that introduced support for a given feature in a given software
release train. Unless noted otherwise, subsequent releases of that software release train also support that
feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support.
To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
MPLS Layer 3 VPNs Inter-AS and CSC Configuration Guide, Cisco IOS Release 12.4T
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MPLS VPN Carrier Supporting Carrier Using LDP and an IGP
Glossary
Table 6
Feature Information for MPLS VPN CSC with LDP and IGP
Feature Name
Releases
Feature Configuration Information
MPLS VPN Carrier Supporting
Carrier
12.0(14)ST
This feature enables you to set up
and create an MPLS VPN CSC
network that uses LDP to
transport MPLS labels and an
IGP to transport routes.
12.0(16)ST
12.2(8)T
12.0(21)ST
12.0(22)S
12.0(23)S
In 12.0(14)ST, this feature was
introduced.
In 12.0(16)ST, this feature was
integrated.
In 12.2(8)T, this feature was
integrated.
In 12.0(21)ST, this feature was
integrated.
In 12.0(22)S, this feature was
integrated.
In 12.0(23)S, this feature was
integrated.
This feature uses no new or
modified commands.
Glossary
ASBR -- Autonomous System Boundary router. A router that connects one autonomous system to another.
autonomous system --A collection of networks under a common administration sharing a common routing
strategy.
BGP --Border Gateway Protocol. An interdomain routing protocol that exchanges network reachability
information with other BGP systems (which may be within the same autonomous system or between
multiple autonomous systems).
CE router--customer edge router. A router that is part of a customer network and that interfaces to a
provider edge (PE) router. CE routers do not recognize associated MPLS VPNs.
CSC --Carrier Supporting Carrier. A hierarchical VPN model that allows small service providers, or
customer carriers, to interconnect their IP or MPLS networks over an MPLS backbone. This eliminates the
need for customer carriers to build and maintain their own MPLS backbone.
eBGP --external Border Gateway Protocol. A BGP between routers located within different autonomous
systems. When two routers, located in different autonomous systems, are more than one hop away from one
another, the eBGP session between the two routers is considered a multihop BGP.
edge router--A router that is at the edge of the network. It defines the boundary of the MPLS network. It
receives and transmits packets. Also referred to as edge label switch router and label edge router.
iBGP --internal Border Gateway Protocol. A BGP between routers within the same autonomous system.
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IGP --Interior Gateway Protocol. Internet protocol used to exchange routing information within a single
autonomous system. Examples of common Internet IGP protocols include IGRP, OSPF, IS-IS, and RIP.
IP --Internet Protocol. Network layer protocol in the TCP/IP stack offering a connectionless internetwork
service. IP provides features for addressing, type-of-service specification, fragmentation and reassembly,
and security. Defined in RFC 791.
LDP --Label Distribution Protocol. A standard protocol between MPLS-enabled routers to negotiate the
labels (addresses) used to forward packets.
LFIB --Label Forwarding Information Base. Data structure used in MPLS to hold information about
incoming and outgoing labels and associated Forwarding Equivalence Class (FEC) packets.
MP-BGP --Multiprotocol BGP.
MPLS --Multiprotocol Label Switching. The name of the IETF working group responsible for label
switching, and the name of the label switching approach it has standardized.
NLRI --Network Layer Reachability Information. The BGP sends routing update messages containing
NLRI to describe a route and how to get there. In this context, an NLRI is a prefix. A BGP update message
carries one or more NLRI prefixes and the attributes of a route for the NLRI prefixes; the route attributes
include a BGP next hop gateway address and extended community values.
NSF --Nonstop forwarding enables routers to continuously forward IP packets following a Route Processor
takeover or switchover to another Route Processor. NSF maintains and updates Layer 3 routing and
forwarding information in the backup Route Processor to ensure that IP packets and routing protocol
information are forwarded continuously during the switchover and route convergence process.
PE router--provider edge router. A router that is part of a service provider’s network. It is connected to a
customer edge (CE) router. All MPLS VPN processing occurs in the PE router.
QoS --quality of service. Measure of performance for a transmission system that indicates its transmission
quality and service availability.
RD --route distinguisher. An 8-byte value that is concatenated with an IPv4 prefix to create a unique VPNIPv4 prefix.
RT --route target. Extended community attribute used to identify the VRF routing table into which a prefix
is imported.
SLA --Service Level Agreement given to VPN subscribers.
VPN --Virtual Private Network. A secure MPLS-based network that shares resources on one or more
physical networks (typically implemented by one or more service providers). A VPN contains
geographically dispersed sites that can communicate securely over a shared backbone network.
VRF --VPN routing and forwarding instance. Routing information that defines a VPN site that is attached
to a PE router. A VRF consists of an IP routing table, a derived forwarding table, a set of interfaces that use
the forwarding table, and a set of rules and routing protocols that determine what goes into the forwarding
table.
Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S.
and other countries. To view a list of Cisco trademarks, go to this URL: www.cisco.com/go/trademarks.
Third-party trademarks mentioned are the property of their respective owners. The use of the word partner
does not imply a partnership relationship between Cisco and any other company. (1110R)
Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be
actual addresses and phone numbers. Any examples, command display output, network topology diagrams,
MPLS Layer 3 VPNs Inter-AS and CSC Configuration Guide, Cisco IOS Release 12.4T
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MPLS VPN Carrier Supporting Carrier Using LDP and an IGP
and other figures included in the document are shown for illustrative purposes only. Any use of actual IP
addresses or phone numbers in illustrative content is unintentional and coincidental.
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MPLS VPN Inter-AS with ASBRs Exchanging
VPN-IPv4 Addresses
The MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses feature allows a Multiprotocol
Label Switching (MPLS) Virtual Private Network (VPN) to span service providers and autonomous
systems. This module explains how to enable Autonomous System Boundary Routers (ASBRs) to use
Exterior Border Gateway Protocol (EBGP) to exchange IPv4 Network Layer Reachability Information
(NLRI) in the form of VPN-IPv4 addresses.
•
•
•
•
•
•
Finding Feature Information, page 119
Prerequisites for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses, page 119
Restrictions for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses, page 121
Information About MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses, page 121
How to Configure MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses, page 129
Configuration Examples for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses,
page 135
Additional References, page 150
Feature Information for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses, page
151
•
•
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest feature
information and caveats, see the release notes for your platform and software release. To find information
about the features documented in this module, and to see a list of the releases in which each feature is
supported, see the Feature Information Table at the end of this document.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support.
To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Prerequisites for MPLS VPN Inter-AS with ASBRs
Exchanging VPN-IPv4 Addresses
•
Before you configure EBGP routing between autonomous systems or subautonomous systems in an
MPLS VPN, ensure that you have properly configured all MPLS VPN routing instances and sessions.
The configuration tasks outlined in this section build from those configuration tasks. Perform the
following tasks as described in the Configuring MPLS Layer 3 VPNs module:
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Prerequisites for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses
•
◦ Define VPN routing instances
◦ Configure BGP routing sessions in the MPLS core
◦ Configure PE-to-PE routing sessions in the MPLS core
◦ Configure BGP PE-to-CE routing sessions
◦ Configure a VPN-IPv4 EBGP session between directly connected ASBRs
This feature is supported on the Cisco 12000 series router line cards listed in the table below.
Table 7
Cisco 12000 Series Line Card Support Added for Cisco IOS Releases
Type
Line Cards
Cisco IOS Release Added
Packet over SONET (POS)
4-Port OC-3 POS
12.0(16)ST
1-Port OC-12 POS
12.0(17)ST
8-Port OC-3 POS
12.0(22)S
16-Port OC-3 POS
4-Port OC-12 POS
1-Port OC-48 POS
4-Port OC-3 POS ISE
8-Port OC-3 POS ISE
16 x OC-3 POS ISE
4-Port OC-12 POS ISE
1-Port OC-48 POS ISE
Electrical interface
6-Port DS3
12.0(21)ST
12-Port DS3
12.0(22)S
6-Port E3
12-Port E3
Ethernet
ATM
3-Port GbE
12.0(23)S
1-Port 10-GbE Modular GbE/FE
12.0(24)S
4-Port OC-3 ATM
12.0(16)ST
1-Port OC-12 ATM
12.0(17)ST
4-Port OC-12 ATM
12.0(23)S
8-Port OC-3 ATM
Channelized interface
2-Port CHOC-3
6-Port Ch T3 (DS1)
1-Port CHOC-12 (DS3)
1-Port CHOC-12 (OC-3)
4-Port CHOC-12 ISE
1-Port CHOC-48 ISE
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12.0(22)S
MPLS VPN Inter-AS Introduction
Restrictions for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses
Restrictions for MPLS VPN Inter-AS with ASBRs Exchanging
VPN-IPv4 Addresses
Multihop VPN-IPv4 EBGP is not supported.
Information About MPLS VPN Inter-AS with ASBRs
Exchanging VPN-IPv4 Addresses
• MPLS VPN Inter-AS Introduction, page 121
• Benefits of MPLS VPN Inter-AS, page 121
• Use of Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses, page 122
• Information Exchange in an MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses,
page 122
MPLS VPN Inter-AS Introduction
An autonomous system is a single network or group of networks that is controlled by a common system
administration group and that uses a single, clearly defined routing protocol.
As VPNs grow, their requirements expand. In some cases, VPNs need to reside on different autonomous
systems in different geographic areas. Also, some VPNs need to extend across multiple service providers
(overlapping VPNs). Regardless of the complexity and location of the VPNs, the connection between
autonomous systems must be seamless to the customer.
Benefits of MPLS VPN Inter-AS
An MPLS VPN Inter-AS provides the following benefits:
•
Allows a VPN to cross more than one service provider backbone: Service providers running separate
autonomous systems can jointly offer MPLS VPN services to the same customer. A VPN can begin at
one customer site and traverse different VPN service provider backbones before arriving at another
site of the same customer. Previously, MPLS VPN could travers only e a single BGP autonomous
system service provider backbone. This feature allows multiple autonomous systems to form a
continuous (and seamless) network between customer sites of a service provider.
•
Allows a VPN to exist in different areas: A service provider can create a VPN in different geographic
areas. Having all VPN traffic flow through one point (between the areas) allows for better rate control
of network traffic between the areas.
•
Allows confederations to optimize IBGP meshing: Internal Border Gateway Protocol (IBGP) meshing
in an autonomous system is more organized and manageable. An autonomous system can be divided
into multiple, separate subautonomous systems and then classify them into a single confederation
(even though the entire VPN backbone appears as a single autonomous system). This capability allows
a service provider to offer MPLS VPNs across the confederation because it supports the exchange of
labeled VPN-IPv4 NLRI between the subautonomous systems that form the confederation.
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Use of Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses
Transmission of Information in an MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses
Use of Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses
Separate autonomous systems from different service providers can communicate by exchanging IPv4 NLRI
in the form of VPN-IPv4 addresses. The ASBRs use EBGP to exchange that information. Then an Interior
Gateway Protocol (IGP) distributes the network layer information for VPN-IPv4 prefixes throughout each
VPN and each autonomous system. Routing information uses the following protocols:
•
•
Within an autonomous system, routing information is shared using an IGP.
Between autonomous systems, routing information is shared using an EBGP. An EBGP allows a
service provider to set up an interdomain routing system that guarantees the loop-free exchange of
routing information between separate autonomous systems.
The primary function of an EBGP is to exchange network reachability information between autonomous
systems, including information about the list of autonomous system routes. The autonomous systems use
EBGP border edge routers to distribute the routes, which include label switching information. Each border
edge router rewrites the next hop and labels. See the Information Exchange in an MPLS VPN Inter-AS
with ASBRs Exchanging VPN-IPv4 Addresses, page 122 section for more information.
Interautonomous system configurations supported in an MPLS VPN are as follows:
•
•
Interprovider VPN-- MPLS VPNs that include two or more autonomous systems, connected by
separate border edge routers. The autonomous systems exchange routes using EBGP. No IGP or
routing information is exchanged between the autonomous systems.
BGP confederations-- MPLS VPNs that divide a single autonomous system into multiple
subautonomous systems, and classify them as a single, designated confederation. The network
recognizes the confederation as a single autonomous system. The peers in the different autonomous
systems communicate over EBGP sessions; however, they can exchange route information as if they
were IBGP peers.
Information Exchange in an MPLS VPN Inter-AS with ASBRs Exchanging
VPN-IPv4 Addresses
This section contains the following topics:
• Transmission of Information in an MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4
Addresses, page 122
• Exchange of VPN Routing Information in an MPLS VPN Inter-AS with ASBRs Exchanging VPNIPv4 Addresses, page 124
• Packet Forwarding Between MPLS VPN Inter-AS Systems with ASBRs Exchanging VPN-IPv4
Addresses, page 126
• Use of a Confederation for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses,
page 128
Transmission of Information in an MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4
Addresses
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MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses
Transmission of Information in an MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses
The figure below illustrates one MPLS VPN consisting of two separate autonomous systems. Each
autonomous system operates under different administrative control and runs a different IGP. Service
providers exchange routing information through EBGP border edge routers (ASBR1, ASBR2).
Figure 14
EBGP Connection Between Two MPLS VPN Inter-AS Systems with ASBRs Exchanging VPN-IPv4
Addresses
This configuration uses the following process to transmit information:
SUMMARY STEPS
1. The provider edge router (PE-1) assigns a label for a route before distributing that route. The PE router
uses the multiprotocol extensions of BGP to transmit label mapping information. The PE router
distributes the route as a VPN-IPv4 address. The address label and the VPN identifier are encoded as
part of the NLRI.
2. The two route reflectors (RR-1 and RR-2) reflect VPN-IPv4 internal routes within the autonomous
system. The autonomous systems’ border edge routers (ASBR1 and ASBR2) advertise the VPN-IPv4
external routes.
3. The EBGP border edge router (ASBR1) redistributes the route to the next autonomous system
(ASBR2). ASBR1 specifies its own address as the value of the EBGP next-hop attribute and assigns a
new label. The address ensures the following:
4. The EBGP border edge router (ASBR2) redistributes the route in one of the following ways, depending
on its configuration:
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DETAILED STEPS
Step 1
Step 2
Step 3
The provider edge router (PE-1) assigns a label for a route before distributing that route. The PE router uses the
multiprotocol extensions of BGP to transmit label mapping information. The PE router distributes the route as a VPNIPv4 address. The address label and the VPN identifier are encoded as part of the NLRI.
The two route reflectors (RR-1 and RR-2) reflect VPN-IPv4 internal routes within the autonomous system. The
autonomous systems’ border edge routers (ASBR1 and ASBR2) advertise the VPN-IPv4 external routes.
The EBGP border edge router (ASBR1) redistributes the route to the next autonomous system (ASBR2). ASBR1
specifies its own address as the value of the EBGP next-hop attribute and assigns a new label. The address ensures the
following:
•
•
Step 4
That the next-hop router is always reachable in the service provider (P) backbone network.
That the label assigned by the distributing router is properly interpreted. (The label associated with a route must
be assigned by the corresponding next-hop router.)
The EBGP border edge router (ASBR2) redistributes the route in one of the following ways, depending on its
configuration:
•
•
If the IBGP neighbors are configured with the neighbor next-hop-self command, ASBR2 changes the next-hop
address of updates received from the EBGP peer, then forwards it.
If the IBGP neighbors are not configured with the neighbor next-hop-self command, the next-hop address does
not get changed. ASBR2 must propagate a host route for the EBGP peer through the IGP. To propagate the
EBGP VPN-IPv4 neighbor host route, use the redistribute connected subnets command. The EBGP VPN-IPv4
neighbor host route is automatically installed in the routing table when the neighbor comes up. This is essential to
establish the label switched path between PE routers in different autonomous systems.
Exchange of VPN Routing Information in an MPLS VPN Inter-AS with ASBRs Exchanging
VPN-IPv4 Addresses
Autonomous systems exchange VPN routing information (routes and labels) to establish connections. To
control connections between autonomous systems, the PE routers and EBGP border edge routers maintain a
Label Forwarding Information Base (LFIB). The LFIB manages the labels and routes that the PE routers
and EBGP border edge routers receive during the exchange of VPN information.
The figure below illustrates the exchange of VPN route and label information between autonomous
systems. The autonomous systems use the following conditions to exchange VPN routing information:
•
•
Routing information includes:
◦ The destination network (N)
◦ The next-hop field associated with the distributing router
◦ A local MPLS label (L)
An RD1: route distinguisher is part of a destination network address. It makes the VPN-IPv4 route
globally unique in the VPN service provider environment.
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•
The ASBRs are configured to change the next-hop (next hop-self) when sending VPN-IPv4 NLRIs to
the IBGP neighbors. Therefore, the ASBRs must allocate a new label when they forward the NLRI to
the IBGP neighbors.
Figure 15
Exchanging Routes and Labels Between MPLS VPN Inter-AS Systems with ASBRs Exchanging
VPN-IPv4 Addresses
The figure below illustrates the exchange of VPN route and label information between autonomous
systems. The only difference is that ASBR2 is configured with the redistribute connected command,
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Packet Forwarding Between MPLS VPN Inter-AS Systems with ASBRs Exchanging VPN-IPv4 Addresses
which propagates the host routes to all PEs. The redistribute connected command is necessary because
ASBR2 is not configured to change the next-hop address.
Figure 16
Exchanging Routes and Labels with the redistribute connected Command in an MPLS VPN Inter-AS
with ASBRs Exchanging VPN-IPv4 Addresses
Packet Forwarding Between MPLS VPN Inter-AS Systems with ASBRs Exchanging VPNIPv4 Addresses
The figure below illustrates how packets are forwarded between autonomous systems in an interprovider
network using the following packet forwarding method.
Packets are forwarded to their destination by means of MPLS. Packets use the routing information stored in
the LFIB of each PE router and EBGP border edge router.
The service provider VPN backbone uses dynamic label switching to forward labels.
Each autonomous system uses standard multilevel labeling to forward packets between the edges of the
autonomous system routers (for example, from CE-5 to PE-3). Between autonomous systems, only a single
level of labeling is used, corresponding to the advertised route.
A data packet carries two levels of labels when traversing the VPN backbone:
•
The first label (IGP route label) directs the packet to the correct PE router or EBGP border edge router.
(For example, the IGP label of ASBR2 points to the ASBR2 border edge router.)
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•
The second label (VPN route label) directs the packet to the appropriate PE router or EBGP border
edge router.
Figure 17
Forwarding Packets Between MPLS VPN Inter-AS Systems with ASBRs Exchanging VPN-IPv4
Addresses
The figure below shows the same packet forwarding method as described in the figure above, except the
EBGP router (ASBR1) forwards the packet without reassigning it a new label.
Figure 18
Forwarding Packets Without a New Label Assignment Between MPLS VPN Inter-AS Systems with
ASBRs Exchanging VPN-IPv4 Addresses
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Use of a Confederation for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses
Use of a Confederation for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4
Addresses
A confederation is multiple subautonomous systems grouped together. A confederation reduces the total
number of peer devices in an autonomous system. A confederation divides an autonomous system into
subautonomous systems and assigns a confederation identifier to the autonomous systems. A VPN can span
service providers running in separate autonomous systems or in multiple subautonomous systems that form
a confederation.
In a confederation, each subautonomous system is fully meshed with other subautonomous systems. The
subautonomous systems communicate using an IGP, such as Open Shortest Path First (OSPF) or
Intermediate System-to-Intermediate System (IS-IS). Each subautonomous system also has an EBGP
connection to the other subautonomous systems. The confederation EBGP (CEBGP) border edge routers
forward next-hop-self addresses between the specified subautonomous systems. The next-hop-self address
forces the BGP to use a specified address as the next hop rather than letting the protocol choose the next
hop.
You can configure a confederation with separate subautonomous systems in either of two ways:
•
•
Note
You can configure a router to forward next-hop-self addresses between only the CEBGP border edge
routers (both directions). The subautonomous systems (IBGP peers) at the subautonomous system
border do not forward the next-hop-self address. Each subautonomous system runs as a single IGP
domain. However, the CEBGP border edge router addresses are known in the IGP domains.
You can configure a router to forward next-hop-self addresses between the CEBGP border edge
routers (both directions) and within the IBGP peers at the subautonomous system border. Each
subautonomous system runs as a single IGP domain but also forwards next-hop-self addresses between
the PE routers in the domain. The CEBGP border edge router addresses are known in the IGP
domains.
The figures above illustrate how two autonomous systems exchange routes and forward packets.
Subautonomous systems in a confederation use a similar method of exchanging routes and forwarding
packets.
The figure below illustrates a typical MPLS VPN confederation configuration. In this confederation
configuration:
•
•
The two CEBGP border edge routers exchange VPN-IPv4 addresses with labels between the two
subautonomous systems.
The distributing router changes the next-hop addresses and labels and uses a next-hop-self address.
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•
IGP-1 and IGP-2 know the addresses of CEBGP-1 and CEBGP-2.
Figure 19
EBGP Connection Between Two Subautonomous Systems in a Confederation
In this confederation configuration:
•
•
•
CEBGP border edge routers function as neighboring peers between the subautonomous systems. The
subautonomous systems use EBGP to exchange route information.
Each CEBGP border edge router (CEBGP-1, CEBGP-2) assigns a label for the route before
distributing the route to the next subautonomous system. The CEBGP border edge router distributes
the route as a VPN-IPv4 address by using the multiprotocol extensions of BGP. The label and the VPN
identifier are encoded as part of the NLRI.
Each PE and CEBGP border edge router assigns its own label to each VPN-IPv4 address prefix before
redistributing the routes. The CEBGP border edge routers exchange VPN-IPv4 addresses with the
labels. The next-hop-self address is included in the label (as the value of the EBGP next-hop attribute).
Within the subautonomous systems, the CEBGP border edge router address is distributed throughout
the IBGP neighbors, and the two CEBGP border edge routers are known to both confederations.
How to Configure MPLS VPN Inter-AS with ASBRs
Exchanging VPN-IPv4 Addresses
• Configuring the ASBRs to Exchange VPN-IPv4 Addresses, page 130
• Configuring EBGP Routing to Exchange VPN Routes Between Subautonomous Systems in a
Confederation, page 131
• Verifying Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses, page 134
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Configuring the ASBRs to Exchange VPN-IPv4 Addresses
To configure an EBGP ASBR to exchange VPN-IPv4 routes with another autonomous system, perform this
task.
Note
Issue the redistribute connected subnets command in the IGP configuration portion of the router to
propagate host routes for VPN-IPv4 EBGP neighbors to other routers and provider edge routers.
Alternatively, you can specify the next-hop-self address when you configure IBGP neighbors.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. no bgp default route-target filter
5. address-family vpnv5 [unicast]
6. neighbor peer-group-name remote-as as-number
7. neighbor peer-group-name activate
8. exit-address-family
9. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Example:
Creates an EBGP routing process and assigns it an autonomous
system number.
•
The autonomous system number is passed along and identifies
the router to EBGP routers in another autonomous system.
Router(config)# router bgp 1
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Command or Action
Purpose
Step 4 no bgp default route-target filter
Disables BGP route-target filtering and places the router in
configuration mode.
•
Example:
All received BGP VPN-IPv4 routes are accepted by the router.
Router(config)# no bgp default routetarget filter
Step 5 address-family vpnv5 [unicast]
Configures a routing session to carry VPNv4 addresses across the
VPN backbone and places the router in address family configuration
mode.
Example:
•
Router(config-router)# address-family
vpnv4
Step 6 neighbor peer-group-name remote-as as-number
•
Enters the address family configuration mode and specifies a
neighboring EBGP peer group.
•
Example:
Each address has been made globally unique by the addition of
an 8-byte route distinguisher (RD).
The unicast keyword specifies a unicast prefix.
This EBGP peer group is identified to the specified autonomous
system.
Router(config-router-af)# neighbor 1
remote-as 2
Step 7 neighbor peer-group-name activate
Activates the advertisement of the VPNv4 address family to a
neighboring EBGP router.
Example:
Router(config-router-af)# neighbor 1
activate
Step 8 exit-address-family
Exits from the address family submode of the router configuration
mode.
Example:
Router(config-router-af)# exit-addressfamily
Step 9 end
Exits to privileged EXEC mode.
Example:
Router(config)# end
Configuring EBGP Routing to Exchange VPN Routes Between
Subautonomous Systems in a Confederation
Perform this task to configure EBGP routing to exchange VPN routes between subautonomous systems in a
confederation.
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Note
To ensure that the host routes for VPN-IPv4 EBGP neighbors are propagated (by means of the IGP) to the
other routers and provider edge routers, specify the redistribute connected command in the IGP
configuration portion of the CEBGP router. If you are using OSPF, make sure that the OSPF process is not
enabled on the CEBGP interface where the “redistribute connected” subnet exists.
Note
In this confederation, subautonomous system IGP domains must know the addresses of CEBGP-1 and
CEBGP-2. If you do not specify a next-hop-self address as part of the router configuration, ensure that the
addresses of all PE routers in the subautonomous system are distributed throughout the network, not just
the addresses of CEBGP-1 and CEBGP-2.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp sub-autonomous-system
4. bgp confederation identifier as-number
5. bgp conferderation peers sub-autonomous-system
6. no bgp default route-target filter
7. address-family vpnv4 [unicast]
8. neighbor peer-group-name remote-as as-number
9. neighbor peer-group-name next-hop-self
10. neighbor peer-group-name activate
11. exit-address-family
12. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
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Command or Action
Purpose
Step 3 router bgp sub-autonomous-system
Creates an EBGP routing process and assigns it an autonomous
system number and enters the router in configuration mode.
•
Example:
The subautonomous system number is passed along to identify
the router to EBGP routers in other subautonomous systems.
Router(config)# router bgp 2
Step 4 bgp confederation identifier as-number
Defines an EBGP confederation by specifying a confederation
identifier associated with each subautonomous system.
•
Example:
The subautonomous systems appear as a single autonomous
system.
Router(config-router)# bgp confederation
identifier 100
Step 5 bgp conferderation peers sub-autonomoussystem
Specifies the subautonomous systems that belong to the confederation
(identifies neighbors of other subautonomous systems within the
confederation as special EBGP peers).
Example:
Router(config-router)# bgp confederation
peers 1
Step 6 no bgp default route-target filter
Disables BGP route-target community filtering. All received BGP
VPN-IPv4 routes are accepted by the router.
Example:
Router(config-router)# no bgp default
route-target filter
Step 7 address-family vpnv4 [unicast]
Configures a routing session to carry VPNv4 addresses across the
VPN backbone. Each address is made globally unique by the addition
of an 8-byte RD. Enters address family configuration mode.
Example:
•
The unicast keyword specifies a unicast prefix.
Router(config-router)# address-family
vpnv4
Step 8 neighbor peer-group-name remote-as asnumber
Enters the address family configuration mode and specifies a
neighboring EBGP peer group.
•
Example:
This EBGP peer group is identified to the specified
subautonomous system.
Router(config-router-af)# neighbor 1
remote-as 1
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Command or Action
Step 9 neighbor peer-group-name next-hop-self
Purpose
Advertises the router as the next hop for the specified neighbor.
•
Example:
If a next-hop-self address is specified as part of the router
configuration, the redistribute connected command need not be
used.
Router(config-router-af)# neighbor 1
next-hop-self
Step 10 neighbor peer-group-name activate
Activates the advertisement of the VPNv4 address family to a
neighboring PE router in the specified subautonomous system.
Example:
Router(config-router-af)# neighbor R
activate
Step 11 exit-address-family
Exits from the address family submode of the router configuration
mode.
Example:
Router(config-router-af)# exit-addressfamily
Step 12 end
Exits to privileged EXEC mode.
Example:
Router(config)# end
Verifying Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses
Perform this task to display the VPN-IPv4 LFIB entries.
SUMMARY STEPS
1. enable
2. show ip bgp vpnv4 {all | rd route-distinguisher | vrf vrf-name} [summary] [labels]
3. show mpls forwarding-table [network {mask | length} | labels label [-label] | interface interface |
next-hop address | lsp-tunnel [tunnel-id]] [vrf vrf-name] [detail]
4. disable
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DETAILED STEPS
Command or Action
Purpose
Step 1 enable
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 show ip bgp vpnv4 {all | rd route-distinguisher | vrf vrf-name} Displays VPN address information from the BGP table.
[summary] [labels]
• Use the all and labels keywords to display
information about all VPNv4 labels.
Example:
Router# show ip bgp vpnv4 all labels
Step 3 show mpls forwarding-table [network {mask | length} | labels
label [-label] | interface interface | next-hop address | lsptunnel [tunnel-id]] [vrf vrf-name] [detail]
Displays the contents of the MPLS LFIB (such as
VPNv4 prefix/length and BGP next-hop destination for
the route).
Example:
Router# show mpls forwarding-table
Step 4 disable
Exits to user EXEC mode.
Example:
Router# disable
Examples
The sample output from the show mpls forwarding-table command shows how the VPN-IPv4 LFIB
entries appear:
Router# show mpls forwarding-table
Local Outgoing
Prefix
Bytes tag
tag
tag or VC
or Tunnel Id
switched
33
33
10.120.4.0/24
0
35
27
100:12:10.200.0.1/32 \
0
Outgoing
interface
Hs0/0
Next Hop
point2point
Hs0/0
point2point
In this example, the Prefix field appears as a VPN-IPv4 RD, plus the prefix. If the value is longer than the
width of the Prefix column (as illustrated in the last line of the example), the output automatically wraps
onto the next line in the forwarding table, preserving column alignment.
Configuration Examples for MPLS VPN Inter-AS with ASBRs
Exchanging VPN-IPv4 Addresses
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Configuration for Autonomous System 1 CE1 Example
• Configuring MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses Example, page
136
• Configuring MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses in a Confederation
Example, page 143
Configuring MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4
Addresses Example
The network topology in the figure below shows two autonomous systems, which are configured as
follows:
•
•
•
•
•
•
Autonomous system 1 (AS1) includes PE1, P1, and EBGP1. The IGP is OSPF.
Autonomous system 2 (AS2) includes PE2, P2, and EBGP2. The IGP is IS-IS.
CE1 and CE2 belong to the same VPN, which is called VPN1.
The P routers are route reflectors.
EBGP1 is configured with the redistribute connected subnets command.
EBGP2 is configured with the neighbor next-hop-self command.
Figure 20
•
•
•
•
•
•
•
•
Configuring Two Autonomous Systems
Configuration for Autonomous System 1 CE1 Example, page 136
Configuration for Autonomous System 1 PE1 Example, page 137
Configuration for Autonomous System 1 P1 Example, page 138
Configuration for Autonomous System 1 EBGP1 Example, page 138
Configuration for Autonomous System 2 EBGP2 Example, page 139
Configuration for Autonomous System 2 P2 Example, page 140
Configuration for Autonomous System 2 PE2 Example, page 141
Configuration for Autonomous System 2 CE2 Example, page 142
Configuration for Autonomous System 1 CE1 Example
The following example shows how to configure CE1 in VPN1 in a topology with two autonomous systems
(see the figure above):
CE1: Burlington
!
interface Loopback1
ip address aa.0.0.6 255.255.255.255
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Configuration for Autonomous System 1 PE1 Example
!
interface Serial1/3
description wychmere
no ip address
encapsulation frame-relay
frame-relay intf-type dce
!
interface Serial1/3.1 point-to-point
description wychmere
ip address aa.6.2.1 255.255.255.252
frame-relay interface-dlci 22
!
router ospf 1
network aa.0.0.0 0.255.255.255 area 0
Configuration for Autonomous System 1 PE1 Example
The following example shows how to configure PE1 in AS1 in a topology with two autonomous systems
(see the figure above):
PE1: wychmere
!
ip cef
!
ip vrf V1
rd 1:105
route-target export 1:100
route-target import 1:100
!
interface Serial0/0
description Burlington
no ip address
encapsulation frame-relay
no fair-queue
clockrate 2000000
!
interface Serial0/0.3 point-to-point
description Burlington
ip vrf forwarding V1
ip address aa.6.2.2 255.255.255.252
frame-relay interface-dlci 22
!
interface Ethernet0/1
description Vermont
ip address aa.2.2.5 255.255.255.0
tag-switching ip
!
router ospf 1
log-adjacency-changes
network aa.0.0.0 0.255.255.255 area 0
!
router ospf 10 vrf V1
log-adjacency-changes
redistribute bgp 1 metric 100 subnets
network aa.0.0.0 0.255.255.255 area 0
!
router bgp 1
no synchronization
neighbor 1 peer-group
neighbor 1 remote-as 1
neighbor 1 update-source Loopback0
neighbor aa.0.0.2 peer-group R
no auto-summary
!
address-family ipv4 vrf V1
redistribute ospf 10
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
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Configuration for Autonomous System 1 P1 Example
neighbor R activate
neighbor R send-community extended
neighbor aa.0.0.2 peer-group R
no auto-summary
exit-address-family
Configuration for Autonomous System 1 P1 Example
The following example shows how to configure P1 in AS1 in a topology with two autonomous systems
(see the figure above):
P1: Vermont
!
ip cef
!
interface Loopback0
ip address aa.0.0.2 255.255.255.255
!
interface Ethernet0/1
description Ogunquit
ip address aa.2.1.1 255.255.255.0
tag-switching ip
!
interface FastEthernet2/0
description wychmere
ip address aa.2.2.1 255.255.255.0
duplex auto
speed auto
tag-switching ip
!
router ospf 1
log-adjacency-changes
network aa.0.0.0 0.255.255.255 area 0
!
router bgp 1
no synchronization
bgp log-neighbor-changes
neighbor R peer-group
neighbor R remote-as 1
neighbor R update-source Loopback0
neighbor R route-reflector-client
neighbor aa.0.0.4 peer-group R
neighbor aa.0.0.5 peer-group R
!
address-family vpnv4
neighbor R activate
neighbor R route-reflector-client
neighbor R send-community extended
neighbor aa.0.0.4 peer-group R
neighbor aa.0.0.5 peer-group R
exit-address-family
Configuration for Autonomous System 1 EBGP1 Example
The following example shows how to configure EBGP1 in AS1 in a topology with two autonomous
systems (see the figure above):
EBGP1: Ogunquit
!
ip cef
!
interface Loopback0
ip address aa.0.0.4 255.255.255.255
!
EBGP1: Ogunquit
!
ip cef
!
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Configuration for Autonomous System 2 EBGP2 Example
interface Loopback0
ip address aa.0.0.4 255.255.255.255
!
interface Ethernet0/1
description Vermont
ip address aa.2.1.40 255.255.255.0
tag-switching ip
!
interface ATM1/0
description Lowell
no ip address
no atm scrambling cell-payload
no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
description Lowell
ip address aa.0.0.1 255.255.255.252
pvc 1/100
!
router ospf 1
log-adjacency-changes
redistribute connected subnets
network aa.0.0.0 0.255.255.255 area 0
!
router bgp 1
no synchronization
no bgp default route-target filter
bgp log-neighbor-changes
neighbor R peer-group
neighbor R remote-as 1
neighbor R update-source Loopback0
neighbor aa.0.0.2 remote-as 2
neighbor aa.0.0.2 peer-group R
no auto-summary
!
address-family vpnv4
neighbor R activate
neighbor R send-community extended
neighbor aa.0.0.2 activate
neighbor aa.0.0.2 send-community extended
neighbor aa.0.0.2 peer-group R
no auto-summary
exit-address-family
Configuration for Autonomous System 2 EBGP2 Example
The following example shows how to configure EBGP2 in AS2 in a topology with two autonomous
systems (see the figure above):
EBGP2: Lowell
!
ip cef
!
ip vrf V1
rd 2:103
route-target export 1:100
route-target import 1:100
!
interface Loopback0
ip address aa.0.0.3 255.255.255.255
ip router isis
!
interface Loopback1
ip vrf forwarding V1
ip address aa.0.0.3 255.255.255.255
!
interface Serial0/0
description Littleton
no ip address
encapsulation frame-relay
load-interval 30
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no fair-queue
clockrate 2000000
!
interface Serial0/0.2 point-to-point
description Littleton
ip unnumbered Loopback0
ip router isis
tag-switching ip
frame-relay interface-dlci 23
!
interface ATM1/0
description Ogunquit
no ip address
atm clock INTERNAL
no atm scrambling cell-payload
no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
description Ogunquit
ip address aa.0.0.2 255.255.255.252
pvc 1/100
!
router isis
net 49.0002.0000.0000.0003.00
!
router bgp 2
no synchronization
no bgp default route-target filter
bgp log-neighbor-changes
neighbor aa.0.0.1 remote-as 1
neighbor aa.0.0.8 remote-as 2
neighbor aa.0.0.8 update-source Loopback0
neighbor aa.0.0.8 next-hop-self
!
address-family ipv4 vrf V1
redistribute connected
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor aa.0.0.1 activate
neighbor aa.0.0.1 send-community extended
neighbor aa.0.0.8 activate
neighbor aa.0.0.8 next-hop-self
neighbor aa.0.0.8 send-community extended
exit-address-family
Configuration for Autonomous System 2 P2 Example
The following example shows how to configure P2 in AS2 in a topology with two autonomous systems
(see the figure above):
P2: Littleton
!
ip cef
!
ip vrf V1
rd 2:108
route-target export 1:100
route-target import 1:100
!
interface Loopback0
ip address aa.0.0.8 255.255.255.255
ip router isis
!
interface Loopback1
ip vrf forwarding V1
ip address aa.0.0.8 255.255.255.255
!
interface FastEthernet0/0
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description Pax
ip address aa.9.1.2 255.255.255.0
ip router isis
tag-switching ip
!
interface Serial5/0
description Lowell
no ip address
encapsulation frame-relay
frame-relay intf-type dce
!
interface Serial5/0.1 point-to-point
description Lowell
ip unnumbered Loopback0
ip router isis
tag-switching ip
frame-relay interface-dlci 23
!
router isis
net aa.0002.0000.0000.0008.00
!
router bgp 2
no synchronization
bgp log-neighbor-changes
neighbor R peer-group
neighbor R remote-as 2
neighbor R update-source Loopback0
neighbor R route-reflector-client
neighbor aa.0.0.3 peer-group R
neighbor aa.0.0.9 peer-group R
!
address-family ipv4 vrf V1
redistribute connected
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor R activate
neighbor R route-reflector-client
neighbor R send-community extended
neighbor aa.0.0.3 peer-group R
neighbor aa.0.0.9 peer-group R
exit-address-family
Configuration for Autonomous System 2 PE2 Example
The following example shows how to configure PE2 in AS2 in a topology with two autonomous systems
(see the figure above):
PE2: Pax
!
ip cef
!
ip vrf V1
rd 2:109
route-target export 1:100
route-target import 1:100
!
interface Loopback0
ip address aa.0.0.9 255.255.255.255
ip router isis
!
interface Loopback1
ip vrf forwarding V1
ip address aa.0.0.9 255.255.255.255
!
interface Serial0/0
description Bethel
no ip address
encapsulation frame-relay
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frame-relay intf-type dce
no fair-queue
clockrate 2000000
!
interface Serial0/0.1 point-to-point
description Bethel
ip vrf forwarding V1
ip unnumbered Loopback1
frame-relay interface-dlci 24
!
interface FastEthernet0/1
description Littleton
ip address aa.9.1.1 255.255.255.0
ip router isis
tag-switching ip
!
router ospf 10 vrf V1
log-adjacency-changes
redistribute bgp 2 subnets
network aa.0.0.0 0.255.255.255 area 0
!
router isis
net 49.0002.0000.0000.0009.00
!
router bgp 2
no synchronization
bgp log-neighbor-changes
neighbor aa.0.0.8 remote-as 2
neighbor aa.0.0.8 update-source Loopback0
!
address-family ipv4 vrf V1
redistribute connected
redistribute ospf 10
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor aa.0.0.8 activate
neighbor aa.0.0.8 send-community extended
exit-address-family v
Configuration for Autonomous System 2 CE2 Example
The following example shows how to configure CE2 in VPN1 in a topology with two autonomous systems
(see the figure above):
CE2: Bethel
!
interface Loopback0
ip address 1.0.0.11 255.255.255.255
!
interface Serial0
description Pax
no ip address
encapsulation frame-relay
no fair-queue
clockrate 2000000
!
interface Serial0.1 point-to-point
description Pax
ip unnumbered Loopback0
frame-relay interface-dlci 24
!
router ospf 1
network aa.0.0.0 0.255.255.255 area 0
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Configuration for Autonomous System 1 CE1 Example
Configuring MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4
Addresses in a Confederation Example
The network topology in the figure below shows a single internet service provider, which is partitioning the
backbone with confederations. The autonomous system number of the provider is 100. The two
autonomous systems run their own IGPs and are configured as follows:
•
•
•
•
•
•
Autonomous system 1 (AS1) includes PE1, P1, ASBR1. The IGP is OSPF.
Autonomous system 2 (AS2) includes PE2, P2, ASBR2. The IGP is IS-IS.
CE1 and CE2 belong to the same VPN, which is called VPN1.
The P routers are route reflectors.
ASBR1 is configured with the redistribute connected subnets command.
ASBR2 is configured with the neighbor next-hop-selfcommand.
Figure 21
•
•
•
•
•
•
•
•
Configuring Two Autonomous Systems in a Confederation
Configuration for Autonomous System 1 CE1 Example, page 143
Configuration for Autonomous System 1 PE1 Example, page 144
Configuration for Autonomous System 1 P1 Example, page 145
Configuration for Autonomous System 1 ASBR1 Example, page 145
Configuration for Autonomous System 2 ASBR2 Example, page 146
Configuration for Autonomous System 2 P2 Example, page 147
Configuration for Autonomous System 2 PE2 Example, page 148
Configuration for Autonomous System 2 CE2 Example, page 149
Configuration for Autonomous System 1 CE1 Example
The following example shows how to configure CE1 in VPN1 in a confederation topology (see the figure
above):
CE1: Burlington
!
interface Loopback1
ip address aa.0.0.6 255.255.255.255
!
interface Serial1/3
description wychmere
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no ip address
encapsulation frame-relay
frame-relay intf-type dce
!
interface Serial1/3.1 point-to-point
description wychmere
ip address aa.6.2.1 255.255.255.252
frame-relay interface-dlci 22
!
router ospf 1
network aa.0.0.0 0.255.255.255 area 0
Configuration for Autonomous System 1 PE1 Example
The following example shows how to configure PE1 in AS1 in a confederation topology (see the figure
above):
PE1: wychmere
!
ip cef
!
ip vrf V1
rd 1:105
route-target export 1:100
route-target import 1:100
!
interface Serial0/0
description Burlington
no ip address
encapsulation frame-relay
no fair-queue
clockrate 2000000
!
interface Serial0/0.3 point-to-point
description Burlington
ip vrf forwarding V1
ip address aa.6.2.2 255.255.255.252
frame-relay interface-dlci 22
!
interface Ethernet0/1
description Vermont
ip address aa.2.2.5 255.255.255.0
tag-switching ip
!
router ospf 1
log-adjacency-changes
network aa.0.0.0 0.255.255.255 area 0
!
router ospf 10 vrf V1
log-adjacency-changes
redistribute bgp 1 metric 100 subnets
network aa.0.0.0 0.255.255.255 area 0
!
router bgp 1
no synchronization
bgp confederation identifier 100
bgp confederation identifier 100
neighbor 1 peer-group
neighbor 1 remote-as 1
neighbor 1 update-source Loopback0
neighbor aa.0.0.2 peer-group R
no auto-summary
!
address-family ipv4 vrf V1
redistribute ospf 10
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor R activate
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neighbor R send-community extended
neighbor aa.0.0.2 peer-group R
no auto-summary
exit-address-family
Configuration for Autonomous System 1 P1 Example
The following example shows how to configure P1 in AS1 in a confederation topology (see the figure
above):
P1: Vermont
!
ip cef
!
interface Loopback0
ip address aa.0.0.2 255.255.255.255
!
interface Ethernet0/1
description Ogunquit
ip address 100.2.1.1 255.255.255.0
tag-switching ip
!
interface FastEthernet2/0
description wychmere
ip address aa.2.2.1 255.255.255.0
duplex auto
speed auto
tag-switching ip
!
router ospf 1
log-adjacency-changes
network aa.0.0.0 0.255.255.255 area 0
!
router bgp 1
no synchronization
bgp log-neighbor-changes
bgp confederation identifier 100
neighbor R peer-group
neighbor R remote-as 1
neighbor R update-source Loopback0
neighbor R route-reflector-client
neighbor 100.0.0.4 peer-group R
neighbor 100.0.0.5 peer-group R
!
address-family vpnv4
neighbor R activate
neighbor R route-reflector-client
neighbor R send-community extended
neighbor aa.0.0.4 peer-group R
neighbor aa.0.0.5 peer-group R
exit-address-family
Configuration for Autonomous System 1 ASBR1 Example
The following example shows how to configure ASBR1 in AS1 in a confederation topology (see the figure
above):
EBGP1: Ogunquit
!
ip cef
!
interface Loopback0
ip address aa.0.0.4 255.255.255.255
!
interface Ethernet0/1
description Vermont
ip address aa.2.1.40 255.255.255.0
tag-switching ip
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Configuration for Autonomous System 2 ASBR2 Example
!
interface ATM1/0
description Lowell
no ip address
no atm scrambling cell-payload
no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
description Lowell
ip address aa.0.0.1 255.255.255.252
pvc 1/100
!
router ospf 1
log-adjacency-changes
redistribute connected subnets
network aa.0.0.0 0.255.255.255 area 0
!
router bgp 1
no synchronization
no bgp default route-target filter
bgp log-neighbor-changes
bgp confederation identifier 100
bgp confederation peers 1
neighbor R peer-group
neighbor R remote-as 1
neighbor R update-source Loopback0
neighbor aa.0.0.2 remote-as 2
neighbor aa.0.0.2 next-hop-self
neighbor aa.0.0.2 peer-group R
no auto-summary
!
address-family vpnv4
neighbor R activate
neighbor R send-community extended
neighbor aa.0.0.2 activate
neighbor aa.0.0.2 next-hop-self
neighbor aa.0.0.2 send-community extended
neighbor aa.0.0.2 peer-group R
no auto-summary
exit-address-family
Configuration for Autonomous System 2 ASBR2 Example
The following example shows how to configure ASBR2 in AS2 in a confederation topology (see the figure
above):
EBGP2: Lowell
!
ip cef
!
ip vrf V1
rd 2:103
route-target export 1:100
route-target import 1:100
!
interface Loopback0
ip address aa.0.0.3 255.255.255.255
ip router isis
!
interface Loopback1
ip vrf forwarding V1
ip address aa.0.0.3 255.255.255.255
!
interface Serial0/0
description Littleton
no ip address
encapsulation frame-relay
load-interval 30
no fair-queue
clockrate 2000000
!
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Configuration for Autonomous System 2 P2 Example
interface Serial0/0.2 point-to-point
description Littleton
ip unnumbered Loopback0
ip router isis
tag-switching ip
frame-relay interface-dlci 23
!
interface ATM1/0
description Ogunquit
no ip address
atm clock INTERNAL
no atm scrambling cell-payload
no atm ilmi-keepalive
!
interface ATM1/0.1 point-to-point
description Ogunquit
ip address aa.0.0.2 255.255.255.252
pvc 1/100
!
router isis
net aa.0002.0000.0000.0003.00
!
router bgp 2
no synchronization
no bgp default route-target filter
bgp log-neighbor-changes
bgp confederation identifier 100
bgp confederation peers 1
neighbor aa.0.0.1 remote-as 1
neighbor aa.0.0.1 next-hop-self
neighbor aa.0.0.8 remote-as 2
neighbor aa.0.0.8 update-source Loopback0
neighbor aa.0.0.8 next-hop-self
!
address-family ipv4 vrf V1
redistribute connected
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor aa.0.0.1 activate
neighbor aa.0.0.1 next-hop-self
neighbor aa.0.0.1 send-community extended
neighbor aa.0.0.8 activate
neighbor aa.0.0.8 next-hop-self
neighbor aa.0.0.8 send-community extended
exit-address-family
Configuration for Autonomous System 2 P2 Example
The following example shows how to configure P2 in AS2 in a confederation topology (see the figure
above):
P2: Littleton
!
ip cef
!
ip vrf V1
rd 2:108
route-target export 1:100
route-target import 1:100
!
interface Loopback0
ip address aa.0.0.8 255.255.255.255
ip router isis
!
interface Loopback1
ip vrf forwarding V1
ip address aa.0.0.8 255.255.255.255
!
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interface FastEthernet0/0
description Pax
ip address aa.9.1.2 255.255.255.0
ip router isis
tag-switching ip
!
interface Serial5/0
description Lowell
no ip address
encapsulation frame-relay
frame-relay intf-type dce
!
interface Serial5/0.1 point-to-point
description Lowell
ip unnumbered Loopback0
ip router isis
tag-switching ip
frame-relay interface-dlci 23
!
router isis
net aa.0002.0000.0000.0008.00
!
router bgp 2
no synchronization
bgp log-neighbor-changes
bgp confederation identifier 100
neighbor R peer-group
neighbor R remote-as 2
neighbor R update-source Loopback0
neighbor R route-reflector-client
neighbor aa.0.0.3 peer-group R
neighbor aa.0.0.9 peer-group R
!
address-family ipv4 vrf V1
redistribute connected
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor R activate
neighbor R route-reflector-client
neighbor R send-community extended
neighbor aa.0.0.3 peer-group R
neighbor aa.0.0.9 peer-group R
exit-address-family
Configuration for Autonomous System 2 PE2 Example
The following example shows how to configure PE2 in AS2 in a confederation topology (see the figure
above):
PE2: Pax
!
ip cef
!
ip vrf V1
rd 2:109
route-target export 1:100
route-target import 1:100
!
interface Loopback0
ip address aa.0.0.9 255.255.255.255
ip router isis
!
interface Loopback1
ip vrf forwarding V1
ip address 1.0.0.9 255.255.255.255
!
interface Serial0/0
description Bethel
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no ip address
encapsulation frame-relay
frame-relay intf-type dce
no fair-queue
clockrate 2000000
!
interface Serial0/0.1 point-to-point
description Bethel
ip vrf forwarding V1
ip unnumbered Loopback1
frame-relay interface-dlci 24
!
interface FastEthernet0/1
description Littleton
ip address 200.9.1.1 255.255.255.0
ip router isis
tag-switching ip
!
router ospf 10 vrf V1
log-adjacency-changes
redistribute bgp 2 subnets
network aa.0.0.0 0.255.255.255 area 0
!
router isis
net aa.0002.0000.0000.0009.00
!
router bgp 2
no synchronization
bgp log-neighbor-changes
bgp confederation identifier 100
neighbor aa.0.0.8 remote-as 2
neighbor aa.0.0.8 update-source Loopback0
!
address-family ipv4 vrf V1
redistribute connected
redistribute ospf 10
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor aa.0.0.8 activate
neighbor aa.0.0.8 send-community extended
exit-address-family
Configuration for Autonomous System 2 CE2 Example
The following example shows how to configure CE2 in VPN1 in a confederation topology (see the figure
above):
CE2: Bethel
!
interface Loopback0
ip address aa.0.0.11 255.255.255.255
!
interface Serial0
description Pax
no ip address
encapsulation frame-relay
no fair-queue
clockrate 2000000
!
interface Serial0.1 point-to-point
description Pax
ip unnumbered Loopback0
frame-relay interface-dlci 24
!
router ospf 1
network aa.0.0.0 0.255.255.255 area 0
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Additional References
Additional References
Related Documents
Related Topic
Document Title
MPLS
MPLS Product Literature
Standards
Standard
Title
No new or modified standards are supported by this -feature, and support for existing standards has not
been modified by this feature.
MIBs
MIB
MIBs Link
No new or modified MIBs are supported by this
feature, and support for existing MIBs has not been
modified by this feature.
To locate and download MIBs for selected
platforms, Cisco software releases, and feature sets,
use Cisco MIB Locator found at the following
URL:
http://www.cisco.com/go/mibs
RFCs
RFC
Title
RFC 1700
Assigned Numbers
RFC 1966
BGP Route Reflection: An Alternative to Full Mesh
IBGP
RFC 2842
Capabilities Advertisement with BGP-4
RFC 2858
Multiprotocol Extensions for BGP-4
RFC 3107
Carrying Label Information in BGP-4
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Feature Information for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses
Technical Assistance
Description
Link
The Cisco Support website provides extensive
http://www.cisco.com/techsupport
online resources, including documentation and tools
for troubleshooting and resolving technical issues
with Cisco products and technologies.
To receive security and technical information about
your products, you can subscribe to various
services, such as the Product Alert Tool (accessed
from Field Notices), the Cisco Technical Services
Newsletter, and Really Simple Syndication (RSS)
Feeds.
Access to most tools on the Cisco Support website
requires a Cisco.com user ID and password.
Feature Information for MPLS VPN Inter-AS with ASBRs
Exchanging VPN-IPv4 Addresses
The following table provides release information about the feature or features described in this module.
This table lists only the software release that introduced support for a given feature in a given software
release train. Unless noted otherwise, subsequent releases of that software release train also support that
feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support.
To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Table 8
Feature Information for MPLS VPN Inter-AS with ASBRs Exchanging VPN-IPv4 Addresses
Feature Name
Releases
Feature Information
MPLS VPN--Interautonomous
System Support
12.1(5)T
This feature enables an MPLS
VPN to span service providers
and autonomous systems. This
feature explains how to
configuring the Inter-AS using
the ASBRs to exchange VPNIPv4 Addresses.
12.0(16)ST
12.0(17)ST
12.0(22)S
This feature uses no new or
modified commands.
Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S.
and other countries. To view a list of Cisco trademarks, go to this URL: www.cisco.com/go/trademarks.
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Third-party trademarks mentioned are the property of their respective owners. The use of the word partner
does not imply a partnership relationship between Cisco and any other company. (1110R)
Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be
actual addresses and phone numbers. Any examples, command display output, network topology diagrams,
and other figures included in the document are shown for illustrative purposes only. Any use of actual IP
addresses or phone numbers in illustrative content is unintentional and coincidental.
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IPv4 Routes and MPLS Labels
The MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels feature allows a
Multiprotocol Label Switching (MPLS) Virtual Private Network (VPN) to span service providers and
autonomous systems. This module explains how to configure an MPLS VPN Inter-AS network so that the
Autonomous System Boundary Routers (ASBRs) exchange IPv4 routes with MPLS labels of the provider
edge (PE) routers. Route reflectors (RRs) exchange VPN-IPv4 routes by using multihop, multiprotocol,
external Border Gateway Protocol (eBGP).
•
•
•
•
•
•
•
•
Finding Feature Information, page 153
Prerequisites for MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels,
page 154
Restrictions for MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels, page
155
Information About MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels,
page 155
How to Configure MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels,
page 158
Configuration Examples for MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS
Labels, page 174
Additional References, page 186
Feature Information for MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS
Labels, page 188
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest feature
information and caveats, see the release notes for your platform and software release. To find information
about the features documented in this module, and to see a list of the releases in which each feature is
supported, see the Feature Information Table at the end of this document.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support.
To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
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Prerequisites for MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels
Prerequisites for MPLS VPN Inter-AS with ASBRs
Exchanging IPv4 Routes and MPLS Labels
The network must be properly configured for MPLS VPN operation before you configure MPLS VPN
Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels.
The table below lists the Cisco 12000 series line card support in Cisco IOS S releases.
Table 9
Cisco 12000 Series Line Card Support in Cisco IOS S Releases
Type
Line Cards
Cisco IOS Release Supported
ATM
4-Port OC-3 ATM
12.0(22)S
1-Port OC-12 ATM
12.0(23)S
4-Port OC-12 ATM
12.0(27)S
8-Port OC-3 ATM
Channelized interface
2-Port CHOC-3
12.0(22)S
6-Port Ch T3 (DS1)
12.0(23)S
1-Port CHOC-12 (DS3)
12.0(27)S
1-Port CHOC-12 (OC-3)
4-Port CHOC-12 ISE
1-Port CHOC-48 ISE
Electrical interface
6-Port DS3
12.0(22)S
12-Port DS3
12.0(23)S
6-Port E3
12.0(27)S
12-Port E3
Ethernet
3-Port GbE
12.0(23)S
12.0(27)S
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Restrictions for MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels
Type
Line Cards
Cisco IOS Release Supported
Packet over SONET (POS)
4-Port OC-3 POS
12.0(22)S
8-Port OC-3 POS
12.0(23)S
16-Port OC-3 POS
12.0(27)S
1-Port OC-12 POS
4-Port OC-12 POS
1-Port OC-48 POS
4-Port OC-3 POS ISE
8-Port OC-3 POS ISE
16-Port OC-3 POS ISE
4-Port OC-12 POS ISE
1-Port OC-48 POS ISE
Restrictions for MPLS VPN Inter-AS with ASBRs Exchanging
IPv4 Routes and MPLS Labels
•
•
For networks configured with eBGP multihop, you must configure a label switched path (LSP)
between nonadjacent routers.
The physical interfaces that connect the BGP speakers must support Cisco Express Forwarding or
distributed Cisco Express Forwarding and MPLS.
Information About MPLS VPN Inter-AS with ASBRs
Exchanging IPv4 Routes and MPLS Labels
• MPLS VPN Inter-AS Introduction, page 121
• Benefits of MPLS VPN Inter-AS, page 121
• Information About Using MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS
Labels, page 156
• Benefits of MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels, page 156
• How the Inter-AS Works When ASBRs Exchange IPv4 Routes with MPLS Labels, page 157
MPLS VPN Inter-AS Introduction
An autonomous system is a single network or group of networks that is controlled by a common system
administration group and that uses a single, clearly defined routing protocol.
As VPNs grow, their requirements expand. In some cases, VPNs need to reside on different autonomous
systems in different geographic areas. Also, some VPNs need to extend across multiple service providers
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Information About MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels
(overlapping VPNs). Regardless of the complexity and location of the VPNs, the connection between
autonomous systems must be seamless to the customer.
Benefits of MPLS VPN Inter-AS
An MPLS VPN Inter-AS provides the following benefits:
•
Allows a VPN to cross more than one service provider backbone: Service providers running separate
autonomous systems can jointly offer MPLS VPN services to the same customer. A VPN can begin at
one customer site and traverse different VPN service provider backbones before arriving at another
site of the same customer. Previously, MPLS VPN could travers only e a single BGP autonomous
system service provider backbone. This feature allows multiple autonomous systems to form a
continuous (and seamless) network between customer sites of a service provider.
•
Allows a VPN to exist in different areas: A service provider can create a VPN in different geographic
areas. Having all VPN traffic flow through one point (between the areas) allows for better rate control
of network traffic between the areas.
•
Allows confederations to optimize IBGP meshing: Internal Border Gateway Protocol (IBGP) meshing
in an autonomous system is more organized and manageable. An autonomous system can be divided
into multiple, separate subautonomous systems and then classify them into a single confederation
(even though the entire VPN backbone appears as a single autonomous system). This capability allows
a service provider to offer MPLS VPNs across the confederation because it supports the exchange of
labeled VPN-IPv4 NLRI between the subautonomous systems that form the confederation.
Information About Using MPLS VPN Inter-AS with ASBRs Exchanging IPv4
Routes and MPLS Labels
This feature can configure a MPLS VPN Inter-AS network so that the ASBRs exchange IPv4 routes with
MPLS labels of the PE routers. RRs exchange VPN-IPv4 routes by using multihop, multiprotocol, External
Border Gateway Protocol (eBGP). This method of configuring the Inter-AS system is often called MPLS
VPN Inter-AS--IPv4 BGP Label Distribution.
Benefits of MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and
MPLS Labels
An Inter-AS system can be configured so that the ASBRs exchange the IPv4 routes and MPLS labels has
the following benefits:
•
•
•
•
Saves the ASBRs from having to store all the VPN-IPv4 routes. Using the route reflectors to store the
VPN-IPv4 routes and forward them to the PE routers results in improved scalability compared wtih
configurations where the ASBR holds all of the VPN-IPv4 routes and forwards the routes based on
VPN-IPv4 labels.
Simplifies the configuration at the border of the network by having the route reflectors hold the VPNIPv4 routes.
Enables a non-VPN core network to act as a transit network for VPN traffic. You can transport IPv4
routes with MPLS labels over a non-MPLS VPN service provider.
Eliminates the need for any other label distribution protocol between adjacent LSRs. If two adjacent
label switch routers (LSRs) are also BGP peers, BGP can handle the distribution of the MPLS labels.
No other label distribution protocol is needed between the two LSRs.
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BGP Routing Information
How the Inter-AS Works When ASBRs Exchange IPv4 Routes with MPLS
Labels
A VPN service provider network to exchange IPv4 routes with MPLS labels can be configured. The VPN
service provider network can be configured as follows:
•
•
Route reflectors exchange VPN-IPv4 routes by using multihop, multiprotocol eBGP. This
configuration also preserves the next-hop information and the VPN labels across the autonomous
systems.
A local PE router (for example, PE1 in the figure below) needs to know the routes and label
information for the remote PE router (PE2). This information can be exchanged between the PE
routers and ASBRs in one of two ways:
◦
◦
Internal Gateway Protocol (IGP) and Label Distribution Protocol (LDP): The ASBR can
redistribute the IPv4 routes and MPLS labels it learned from eBGP into IGP and LDP and vice
versa.
Internal Border Gateway Protocol (iBGP) IPv4 label distribution:The ASBR and PE router can
use direct iBGP sessions to exchange VPN-IPv4 and IPv4 routes and MPLS labels.
Alternatively, the route reflector can reflect the IPv4 routes and MPLS labels learned from the ASBR to the
PE routers in the VPN. This is accomplished by the ASBR exchanging IPv4 routes and MPLS labels with
the route reflector. The route reflector also reflects the VPN-IPv4 routes to the PE routers in the VPN. For
example, in VPN1 of the figure below, RR1 reflects to PE1 the VPN-IPv4 routes it learned and IPv4 routes
and MPLS labels learned from ASBR1. Using the route reflectors to store the VPN-IPv4 routes and
forward them through the PE routers and ASBRs allows for a scalable configuration.
•
•
•
BGP Routing Information, page 157
Types of BGP Messages and MPLS Labels, page 158
How BGP Sends MPLS Labels with Routes, page 158
BGP Routing Information
BGP routing information includes the following items:
•
•
A network number (prefix), which is the IP address of the destination.
Autonomous system path, which is a list of the other autonomous systems through which a route
passes on its way to the local router. The first autonomous system in the list is closest to the local
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Types of BGP Messages and MPLS Labels
•
router; the last autonomous system in the list is farthest from the local router and usually the
autonomous system where the route began.
Path attributes, which provide other information about the autonomous system path, for example, the
next hop.
Types of BGP Messages and MPLS Labels
MPLS labels are included in the update messages that a router sends. Routers exchange the following types
of BGP messages:
•
•
•
•
Keepalive messages--Routers exchange keepalive messages to determine if a neighboring router is still
available to exchange routing information. The router sends these messages at regular intervals. (Sixty
seconds is the default for Cisco routers.) The keepalive message does not contain routing data; it
contains only a message header.
Notification messages--When a router detects an error, it sends a notification message.
Open messages--After a router establishes a TCP connection with a neighboring router, the routers
exchange open messages. This message contains the number of the autonomous system to which the
router belongs and the IP address of the router that sent the message.
Update messages--When a router has a new, changed, or broken route, it sends an update message to
the neighboring router. This message contains the NLRI, which lists the IP addresses of the usable
routes. The update message includes any routes that are no longer usable. The update message also
includes path attributes and the lengths of both the usable and unusable paths. Labels for VPN-IPv4
routes are encoded in the update message as specified in RFC 2858. The labels for the IPv4 routes are
encoded in the update message as specified in RFC 3107.
How BGP Sends MPLS Labels with Routes
When BGP (eBGP and iBGP) distributes a route, it can also distribute an MPLS label that is mapped to that
route. The MPLS label mapping information for the route is carried in the BGP update message that
contains the information about the route. If the next hop is not changed, the label is preserved.
When you issue the neighbor send-label command on both BPG routers, the routers advertise to each
other that they can then send MPLS labels with the routes. If the routers successfully negotiate their ability
to send MPLS labels, the routers add MPLS labels to all outgoing BGP updates.
How to Configure MPLS VPN Inter-AS with ASBRs
Exchanging IPv4 Routes and MPLS Labels
To configure MPLS VPN Inter-AS with ASBRs exchanging IPv4 routes and MPLS labels, perform the
tasks in the following sections:
The figure below shows the following sample configuration:
•
•
•
•
The configuration consists of two VPNs.
The ASBRs exchange the IPv4 routes with MPLS labels.
The route reflectors exchange the VPN-IPv4 routes using multihop MPLS eBGP.
The route reflectors reflect the IPv4 and VPN-IPv4 routes to the other routers in their autonomous
system.
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How to Configure MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels
• Configuring the ASBRs to Exchange IPv4 Routes and MPLS Labels, page 159
• Configuring the Route Reflectors to Exchange VPN-IPv4 Routes, page 161
• Configuring the Route Reflector to Reflect Remote Routes in Its Autonomous System, page 163
• Verifying the MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels
Configuration, page 166
Configuring the ASBRs to Exchange IPv4 Routes and MPLS Labels
Perform this task to configure the ASBRs to exchange IPv4 routes and MPLS labels. This configuration
procedure uses ASBR1 as an example.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. neighbor {ip-address | peer-group-name} remote-as as-number
5. address-family ipv4 [multicast | unicast | mdt | vrf vrf-name]
6. neighbor {ip-address | peer-group-name} activate
7. neighborip-address send-label
8. exit-address-family
9. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
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Command or Action
Step 2 configure terminal
Purpose
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Example:
Configures a BGP routing process and places the router in router
configuration mode.
•
Router(config)# router bgp 100
Step 4 neighbor {ip-address | peer-group-name}
remote-as as-number
Example:
Adds an entry to the BGP or multiprotocol BGP neighbor table.
•
•
•
Router(config-router)# neighbor hh.
0.0.1 remote-as 200
Step 5 address-family ipv4 [multicast | unicast |
mdt | vrf vrf-name]
Example:
Router(config-router)# addressfamily ipv4
Step 6 neighbor {ip-address | peer-group-name}
activate
The as-number argument indicates the number of an autonomous
system that identifies the router to other BGP routers and tags the
routing information passed along. Valid numbers are from 0 to 65535.
Private autonomous system numbers that can be used in internal
networks range from 64512 to 65535.
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
The as-number argument specifies the autonomous system to which the
neighbor belongs.
Enters address family configuration mode for configuring routing sessions
such as BGP that use standard IPv4 address prefixes.
•
•
•
•
The multicast keyword specifies IPv4 multicast address prefixes.
The unicast keyword specifies IPv4 unicast address prefixes.
The mdt keyword specifies an IPv4 multicast distribution tree (MDT)
address family session.
The vrf vrf-name keyword and argument specify the name of the VPN
routing and forwarding (VRF) instance to associate with subsequent
IPv4 address family configuration mode commands.
Enables the exchange of information with a neighboring router.
•
•
Example:
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
Router(config-router-af)# neighbor
hh.0.0.1 activate
Step 7 neighborip-address send-label
Example:
Enables a BGP router to send MPLS labels with BGP routes to a
neighboring BGP router.
•
The ip-address argument specifies the IP address of the neighboring
router.
Router(config-router-af)# neighbor
hh.0.0.1 send-label
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Command or Action
Step 8 exit-address-family
Purpose
Exits address family configuration mode.
Example:
Router(config-router-af)# exitaddress-family
Step 9 end
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-router-af)# end
Configuring the Route Reflectors to Exchange VPN-IPv4 Routes
Perform this task to enable the route reflectors to exchange VPN-IPv4 routes by using multihop,
multiprotocol eBGP.
This procedure also specifies that the next hop information and the VPN label are to be preserved across
the autonomous systems. This procedure uses RR1 as an example of the route reflector.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. neighbor {ip-address | peer-group-name} remote-as as-number
5. neighbor {ip-address | peer-group-name} ebgp-multihop [ttl]
6. address-family vpnv4 [unicast]
7. neighbor {ip-address | peer-group-name} activate
8. neighbor {ip-address | peer-group-name} next-hop unchanged
9. exit-address-family
10. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
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Command or Action
Step 2 configure terminal
Purpose
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Example:
Configures a BGP routing process and places the router in router
configuration mode.
•
Router(config)# router bgp 100
The as-number argument indicates the number of an autonomous
system that identifies the router to other BGP routers and tags the
routing information passed along. Valid numbers are from 0 to 65535.
Private autonomous system numbers that can be used in internal
networks range from 64512 to 65535.
The autonomous system number identifies RR1 to routers in other
autonomous systems.
Step 4 neighbor {ip-address | peer-group-name}
remote-as as-number
Example:
Adds an entry to the BGP or multiprotocol BGP neighbor table.
•
•
•
Router(config-router)# neighbor
bb.bb.bb.bb remote-as 200
Step 5 neighbor {ip-address | peer-group-name}
ebgp-multihop [ttl]
Accepts and attempts BGP connections to external peers residing on
networks that are not directly connected.
•
Example:
Router(config-router)# neighbor
bb.bb.bb.bb ebgp-multihop 255
Step 6 address-family vpnv4 [unicast]
Example:
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
The as-number argument specifies the autonomous system to which
the neighbor belongs.
•
•
The ip-address argument specifies the IP address of the BGPspeaking neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
The ttl argument specifies the time-to-live in the range from 1 to 255
hops.
Enters address family configuration mode for configuring routing sessions,
such as BGP sessions, that use standard VPNv4 address prefixes.
•
The optional unicast keyword specifies VPNv4 unicast address
prefixes.
Router(config-router)# addressfamily vpnv4
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Command or Action
Purpose
Step 7 neighbor {ip-address | peer-group-name}
activate
Enables the exchange of information with a neighboring router.
•
•
Example:
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
Router(config-router-af)# neighbor
bb.bb.bb.bb activate
Step 8 neighbor {ip-address | peer-group-name}
next-hop unchanged
Example:
Enables an eBGP multihop peer to propagate the next hop unchanged.
•
•
The ip-address argument specifies the IP address of the next hop.
The peer-group-name argument specifies the name of a BGP peer
group that is the next hop.
Router(config-router-af)# neighbor
ip-address next-hop unchanged
Step 9 exit-address-family
Exits address family configuration mode.
Example:
Router(config-router-af)# exitaddress-family
Step 10 end
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-router)# end
Configuring the Route Reflector to Reflect Remote Routes in Its Autonomous
System
Perform this task to enable the RR to reflect the IPv4 routes and labels learned by the ASBR to the PE
routers in the autonomous system.
This is accomplished by making the ASBR and PE router route reflector clients of the RR. This procedure
also explains how to enable the RR to reflect the VPN-IPv4 routes.
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SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. address-family ipv4 [multicast | unicast | vrf vrf-name]
5. neighbor {ip-address | peer-group-name activate
6. neighbor ip-address route-reflector-client
7. neighbor ip-address send-label
8. exit-address-family
9. address-family vpnv4 [unicast]
10. neighbor {ip-address | peer-group-name} activate
11. neighbor ip-address route-reflector-client
12. exit-address-family
13. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Example:
Router(config)# router bgp 100
Configures a BGP routing process and places the router in router
configuration mode.
•
The as-number argument indicates the number of an autonomous
system that identifies the router to other BGP routers and tags the
routing information passed along. Valid numbers are from 0 to
65535. Private autonomous system numbers that can be used in
internal networks range from 64512 to 65535.
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Command or Action
Purpose
Step 4 address-family ipv4 [multicast | unicast | vrf Enters address family configuration mode for configuring routing
sessions, such as BGP sessions, that use standard IPv4 address prefixes.
vrf-name]
•
•
•
Example:
Router(config-router)# address-family
ipv4
Step 5 neighbor {ip-address | peer-group-name
activate
The multicast keyword specifies IPv4 multicast address prefixes.
The unicast keyword specifies IPv4 unicast address prefixes.
The vrf vrf-name keyword and argument specify the name of the
VRF instance to associate with subsequent IPv4 address family
configuration mode commands.
Enables the exchange of information with a neighboring router.
•
•
Example:
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
Router(config-router-af)# neighbor
ee.ee.ee.ee activate
Step 6 neighbor ip-address route-reflector-client
Configures the router as a BGP route reflector and configures the
specified neighbor as its client.
•
Example:
The ip-address argument specifies the IP address of the BGP
neighbor being configured as a client.
Router(config-router-af)# neighbor
ee.ee.ee.ees route-reflector-client
Step 7 neighbor ip-address send-label
Enables a BGP router to send MPLS labels with BGP routes to a
neighboring BGP router.
•
Example:
The ip-address argument specifies the IP address of the
neighboring router.
Router(config-router-af)# neighbor
ee.ee.ee.ee send-label
Step 8 exit-address-family
Exits address family configuration mode.
Example:
Router(config-router-af)# exit-addressfamily
Step 9 address-family vpnv4 [unicast]
Enters address family configuration mode for configuring routing
sessions, such as BGP sessions, that use standard VPNv4 address
prefixes.
Example:
•
Router(config-router)# address-family
vpnv4
The optional unicast keyword specifies VPNv4 unicast address
prefixes.
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How to Configure MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels
Command or Action
Step 10 neighbor {ip-address | peer-group-name}
activate
Example:
Purpose
Enables the exchange of information with a neighboring router.
•
•
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
Router(config-router-af)# neighbor
ee.ee.ee.ee activate
Step 11 neighbor ip-address route-reflector-client
Enables the RR to pass iBGP routes to the neighboring router.
Example:
Router(config-router-af)# neighbor
ee.ee.ee.ee route-reflector-client
Step 12 exit-address-family
Exits address family configuration mode.
Example:
Router(config-router-af)#
exit-address-family
Step 13 end
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-router-af)# end
Verifying the MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and
MPLS Labels Configuration
If you use ASBRs to distribute the IPv4 labels and route reflectors to distribute the VPN-IPv4 routes, use
the following procedures to help verify the configuration:
The figure below shows the configuration that is referred to in the next several sections.
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Verifying the Route Reflector Configuration
•
•
•
•
•
Verifying the Route Reflector Configuration, page 167
Verifying that CE1 Can Communicate with CE2, page 168
Verifying that PE1 Can Communicate with CE2, page 169
Verifying that PE2 Can Communicate with CE2, page 171
Verifying the ASBR Configuration, page 172
Verifying the Route Reflector Configuration
Perform this task to verify the route reflector configuration.
SUMMARY STEPS
1. enable
2. show ip bgp vpnv4 {all | rd route-distinguisher | vrf vrf-name } [summary] [labels]
3. disable
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
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Command or Action
Step 2 show ip bgp vpnv4 {all | rd routedistinguisher | vrf vrf-name }
[summary] [labels]
Example:
Purpose
(Optional) Displays VPN address information from the BGP table.
•
Use the all and summary keywords to verify that a multihop, multiprotocol
eBGP session exists between the route reflectors and that the VPNv4 routes
are being exchanged between the route reflectors.
The last two lines of the command output show the following information:
•
Router# show ip bgp vpnv4 all
summary
•
Step 3 disable
◦ Prefixes are being learned from PE1 and then passed to RR2.
◦ Prefixes are being learned from RR2 and then passed to PE1.
Use the all and labels keywords to verify that the route reflectors exchange
VPNv4 label information.
(Optional) Exits to user EXEC mode.
Example:
Router# disable
Verifying that CE1 Can Communicate with CE2
Perform this task to verify that router CE1 has NLRI for router CE2.
SUMMARY STEPS
1. enable
2. show ip route [ip-address [mask] [longer-prefixes]] | [protocol [protocol-id]] | [list [access-listnumber | access-list-name]
3. disable
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 show ip route [ip-address [mask] [longer-prefixes]] Displays the current state of the routing table.
| [protocol [protocol-id]] | [list [access-list-number |
• Use the ip-address argument to verify that CE1 has a route to
access-list-name]
CE2.
• Use this command to verify the routes learned by CE1. Make
sure that the route for CE2 is listed.
Example:
Router# show ip route nn.nn.nn.nn
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Command or Action
Step 3 disable
Purpose
(Optional) Exits to privileged EXEC mode.
Example:
Router# disable
Verifying that PE1 Can Communicate with CE2
Perform this task to verify that router PE1 has NLRI for router CE2.
SUMMARY STEPS
1. enable
2. show ip route vrf vrf-name [connected] [protocol [as-number] [tag] [output-modifiers]] [list number
[output-modifiers]] [profile] [static [ []] [summaryoutput-modifiers]] [supernets-only [outputmodifiers]] [traffic-engineering [output-modifiers]]
3. show ip bgp vpnv4 {all | rd route-distinguisher | vrf vrf-name} [ip-prefix | length [longer-prefixes]
[output-modifiers]]] [network-address mask]] longer-prefixes [output-modifiers]] [cidr-only]
[community] [community-list] [dampened-paths] [filter-list] [flap-statistics] [inconsistent-as]
[neighbors] [paths [line]] [peer-group] [quote-regexp] [regexp] [summary] [tags]
4. show ip cef [ vrf vrf-name] [network [mask]] [longer-prefixes] [detail]
5. show mpls forwarding-table [{network {mask | length} | labels label [-label] | interface interface |
next-hop address | lsp-tunnel [tunnel-id]}] [detail]
6. show ip bgp [network] [network-mask] [longer-prefixes]
7. show ip bgp vpnv4 {all | rd route-distinguisher | vrf vrf-name} [summary] [labels]
8. disable
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
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Command or Action
Purpose
Step 2 show ip route vrf vrf-name [connected] [protocol [as-number] (Optional) Displays the IP routing table associated with
a VRF.
[tag] [output-modifiers]] [list number [output-modifiers]]
[profile] [static [ []] [summaryoutput-modifiers]] [supernets• Use this command to verify that router PE1 learns
only [output-modifiers]] [traffic-engineering [outputroutes from router CE2 (nn.nn.nn.nn).
modifiers]]
Example:
Router# show ip route vrf vpn1 nn.nn.nn.nn
Step 3 show ip bgp vpnv4 {all | rd route-distinguisher | vrf vrf-name} (Optional) Displays VPN address information from the
BGP table.
[ip-prefix | length [longer-prefixes] [output-modifiers]]]
[network-address mask]] longer-prefixes [output-modifiers]]
• Use the vrf or all keyword to verify that router PE2
[cidr-only] [community] [community-list] [dampened-paths]
is the BGP next-hop to router CE2.
[filter-list] [flap-statistics] [inconsistent-as] [neighbors]
[paths [line]] [peer-group] [quote-regexp] [regexp]
[summary] [tags]
Example:
Router# show ip bgp vpnv4 vrf vpn1 nn.nn.nn.nn
Example:
Router# show ip bgp vpnv4 all nn.nn.nn.nn
Step 4 show ip cef [ vrf vrf-name] [network [mask]] [longer-prefixes] (Optional) Displays entries in the Forwarding
Information Base (FIB) or displays a summary of the
[detail]
FIB.
Example:
•
Use this command to verify that the Cisco Express
Forwarding entries are correct.
Router# show ip cef vrf vpn1 nn.nn.nn.nn
Step 5 show mpls forwarding-table [{network {mask | length} |
labels label [-label] | interface interface | next-hop address |
lsp-tunnel [tunnel-id]}] [detail]
(Optional) Displays the contents of the MPLS LFIB.
•
Use this command to verify the IGP label for the
BGP next hop router (autonomous system
boundary).
Example:
Router# show mpls forwarding-table
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Command or Action
Purpose
Step 6 show ip bgp [network] [network-mask] [longer-prefixes]
(Optional) Displays entries in the BGP routing table.
•
Example:
Use the show ip bgp command to verify the label
for the remote egress PE router (PE2).
Router# show ip bgp ff.ff.ff.ff
Step 7 show ip bgp vpnv4 {all | rd route-distinguisher | vrf vrf-name} (Optional) Displays VPN address information from the
BGP table.
[summary] [labels]
•
Example:
Use the all and summary keywords to verify the
VPN label of CE2, as advertised by PE2.
Router# show ip bgp vpnv4 all labels
Step 8 disable
(Optional) Exits to user EXEC mode.
Example:
Router# disable
Verifying that PE2 Can Communicate with CE2
Perform this task to ensure that PE2 can access CE2.
SUMMARY STEPS
1. enable
2. show ip route vrf vrf-name [connected] [protocol [as-number] [tag] [output-modifiers]] [list number
[output-modifiers]] [profile] [static [output-modifiers]] [summary[output-modifiers]] [supernets-only
[output-modifiers]] [traffic-engineering [output-modifiers]]
3. show mpls forwarding-table [vrf vrf-name] [{network {mask | length} | labels label [-label] |
interface interface | next-hop address | lsp-tunnel [tunnel-id]}] [detail]
4. show ip bgp vpnv4 { all | rd route-distinguisher | vrf vrf-name} [summary] [labels]
5. show ip cef [ vrf vrf-name] [network [mask]] [longer-prefixes] [detail]
6. disable
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
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Command or Action
Purpose
Step 2 show ip route vrf vrf-name [connected] [protocol [asnumber] [tag] [output-modifiers]] [list number [outputmodifiers]] [profile] [static [output-modifiers]]
[summary[output-modifiers]] [supernets-only [outputmodifiers]] [traffic-engineering [output-modifiers]]
(Optional) Displays the IP routing table associated with a
VRF.
•
Use this command to check the VPN routing and
forwarding table for CE2. The output provides next-hop
information.
Example:
Router# show ip route vrf vpn1 nn.nn.nn.nn
Step 3 show mpls forwarding-table [vrf vrf-name] [{network
(Optional) Displays the contents of the LFIB.
{mask | length} | labels label [-label] | interface interface |
• Use the vrf keyword to check the VPN routing and
next-hop address | lsp-tunnel [tunnel-id]}] [detail]
forwarding table for CE2. The output provides the label
for CE2 and the outgoing interface.
Example:
Router# show mpls forwarding-table vrf vpn1
nn.nn.nn.nn
Step 4 show ip bgp vpnv4 { all | rd route-distinguisher | vrf vrfname} [summary] [labels]
(Optional) Displays VPN address information from the BGP
table.
•
Example:
Use the all and labels keywords to check the VPN label
for CE2 in the multiprotocol BGP table.
Router# show ip bgp vpnv4 all labels
Step 5 show ip cef [ vrf vrf-name] [network [mask]] [longerprefixes] [detail]
(Optional) Displays entries in the FIB or displays a summary
of the FIB.
•
Example:
Use this command to check the Cisco Express
Forwarding entry for CE2. The command output shows
the local label for CE2 and the outgoing interface.
Router# show ip cef vpn1 nn.nn.nn.nn
Step 6 disable
(Optional) Exits to user EXEC mode.
Example:
Router# disable
Verifying the ASBR Configuration
Perform this task to verify that the ASBRs exchange IPv4 routes with MPLS labels or IPv4 routes without
labels as prescribed by a route map.
•
Verifying the ASBR Configuration , page 173
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Verifying the ASBR Configuration
SUMMARY STEPS
1. enable
2. show ip bgp [network] [network-mask] [longer-prefixes]
3. show ip cef [vrf vrf-name] [network [mask]] [longer-prefixes] [detail]
4. disable
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 show ip bgp [network] [network-mask]
[longer-prefixes]
Example:
Router# show ip bgp ff.ff.ff.ff
(Optional) Displays entries in the BGP routing table.
•
Use this command to check that:
◦
◦
◦
◦
ASBR1 receives an MPLS label for PE2 from ASBR2.
ASBR1 receives IPv4 routes for RR2 without labels from ASBR2.
ASBR2 distributes an MPLS label for PE2 to ASBR1.
ASBR2 does not distribute a label for RR2 to ASBR1.
Step 3 show ip cef [vrf vrf-name] [network [mask]] (Optional) Displays entries in the FIB or displays a summary of the FIB.
[longer-prefixes] [detail]
• Use thiscommand from ASBR1 and ASBR2 to check that:
Example:
◦
◦
The Cisco Express Forwarding entry for PE2 is correct.
The Cisco Express Forwarding entry for RR2 is correct.
Router# show ip cef ff.ff.ff.ff
Example:
Router# show ip cef bb.bb.bb.bb
Step 4 disable
(Optional) Exits to user EXEC mode.
Example:
Router# disable
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Provider Examples
Configuration Examples for MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels
Configuration Examples for MPLS VPN Inter-AS with ASBRs
Exchanging IPv4 Routes and MPLS Labels
• Configuring MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels over an
MPLS VPN Service Provider Examples, page 174
• Configuring MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels over a
Non-MPLS VPN Service Provider Examples, page 179
Configuring MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and
MPLS Labels over an MPLS VPN Service Provider Examples
Configuration examples for Inter-AS using BGP to distribute routes and MPLS labels over an MPLS VPN
service provider included in this section are as follows:
The figure below shows two MPLS VPN service providers. The service provider distributes the VPN-IPv4
routes between the route reflectors. The MPLS VPN service providers distribute the IPv4 routes with
MPLS labels between the ASBRs.
The configuration example shows the following two techniques you can use to distribute the VPN-IPv4
routes and the IPv4 routes with MPLS labels of the remote RRs and PEs to the local RRs and PEs:
•
•
Autonomous system 100 uses the RRs to distribute the VPN-IPv4 routes learned from the remote RRs.
The RRs also distribute the remote PE address and label learned from ASBR1 using IPv4 labels.
In Autonomous system 200, the IPv4 routes that ASBR2 learned are redistributed into IGP.
•
•
•
•
Route Reflector 1 Configuration Example (MPLS VPN Service Provider), page 174
ASBR1 Configuration Example (MPLS VPN Service Provider), page 176
Route Reflector 2 Configuration Example (MPLS VPN Service Provider), page 177
ASBR2 Configuration Example (MPLS VPN Service Provider), page 177
Route Reflector 1 Configuration Example (MPLS VPN Service Provider)
The configuration example for RR1 specifies the following:
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•
•
•
RR1 exchanges VPN-IPv4 routes with RR2 using multiprotocol, multihop eBGP.
The VPN-IPv4 next-hop information and the VPN label are preserved across the autonomous systems.
RR1 reflects to PE1:
◦
◦
The VPN-IPv4 routes learned from RR2
The IPv4 routes and MPLS labels learned from ASBR1
ip subnet-zero
ip cef
!
interface Loopback0
ip address aa.aa.aa.aa 255.255.255.255
!
interface Ethernet0/3
ip address dd.0.0.2 255.0.0.0
!
router ospf 10
log-adjacency-changes
auto-cost reference-bandwidth 1000
network aa.aa.aa.aa 0.0.0.0 area 100
network dd.0.0.0 0.255.255.255 area 100
!
router bgp 100
bgp cluster-id 1
bgp log-neighbor-changes
timers bgp 10 30
neighbor ee.ee.ee.ee remote-as 100
neighbor ee.ee.ee.ee update-source Loopback0
neighbor ww.ww.ww.ww remote-as 100
neighbor ww.ww.ww.ww update-source Loopback0
neighbor bb.bb.bb.bb remote-as 200
neighbor bb.bb.bb.bb ebgp-multihop 255
neighbor bb.bb.bb.bb update-source Loopback0
no auto-summary
!
address-family ipv4
neighbor ee.ee.ee.ee activate
neighbor ee.ee.ee.ee route-reflector-client
neighbor ee.ee.ee.ee send-label
neighbor ww.ww.ww.ww activate
neighbor ww.ww.ww.ww route-reflector-client
neighbor ww.ww.ww.ww send-label
no neighbor bb.bb.bb.bb activate
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor ee.ee.ee.ee activate
neighbor ee.ee.ee.ee route-reflector-client
neighbor ee.ee.ee.ee send-community extended
neighbor bb.bb.bb.bb activate
neighbor bb.bb.bb.bb next-hop-unchanged
neighbor bb.bb.bb.bb send-community extended
unchanged
exit-address-family
!
ip default-gateway 3.3.0.1
no ip classless
!
snmp-server engineID local 00000009020000D0584B25C0
snmp-server community public RO
snmp-server community write RW
no snmp-server ifindex persist
snmp-server packetsize 2048
!
end
!IPv4+labels session to PE1
!IPv4+labels session to ASBR1
!VPNv4 session with PE1
!MH-VPNv4 session with RR2
!with next hop
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ASBR1 Configuration Example (MPLS VPN Service Provider)
ASBR1 Configuration Example (MPLS VPN Service Provider)
ASBR1 exchanges IPv4 routes and MPLS labels with ASBR2.
In this example, ASBR1 uses route maps to filter routes:
•
•
A route map called OUT specifies that ASBR1 should distribute the PE1 route (ee.ee) with labels and
the RR1 route (aa.aa) without labels.
A route map called IN specifies that ASBR1 should accept the PE2 route (ff.ff) with labels and the
RR2 route (bb.bb) without labels.
ip subnet-zero
mpls label protocol ldp
!
interface Loopback0
ip address ww.ww.ww.ww 255.255.255.255
!
interface Ethernet0/2
ip address hh.0.0.2 255.0.0.0
!
interface Ethernet0/3
ip address dd.0.0.1 255.0.0.0
mpls label protocol ldp
mpls ip
!
router ospf 10
log-adjacency-changes
auto-cost reference-bandwidth 1000
redistribute connected subnets
passive-interface Ethernet0/2
network ww.ww.ww.ww 0.0.0.0 area 100
network dd.0.0.0 0.255.255.255 area 100
router bgp 100
bgp log-neighbor-changes
timers bgp 10 30
neighbor aa.aa.aa.aa remote-as 100
neighbor aa.aa.aa.aa update-source Loopback0
neighbor hh.0.0.1 remote-as 200
no auto-summary
!
!
address-family ipv4
! Redistributing IGP into BGP
redistribute ospf 10
! so that PE1 & RR1 loopbacks
neighbor aa.aa.aa.aa activate
! get into the BGP table
neighbor aa.aa.aa.aa send-label
neighbor hh.0.0.1 activate
neighbor hh.0.0.1 advertisement-interval 5
neighbor hh.0.0.1 send-label
neighbor hh.0.0.1 route-map IN in
! accepting routes in route map IN.
neighbor hh.0.0.1 route-map OUT out
! distributing routes in route map OUT.
neighbor kk.0.0.1 activate
neighbor kk.0.0.1 advertisement-interval 5
neighbor kk.0.0.1 send-label
neighbor kk.0.0.1 route-map IN in
! accepting routes in route map IN.
neighbor kk.0.0.1 route-map OUT out
! distributing routes in route map OUT.
no auto-summary
no synchronization
exit-address-family
!
ip default-gateway 3.3.0.1
ip classless
!
access-list 1 permit ee.ee.ee.ee log
!Setting up the access lists
access-list 2 permit ff.ff.ff.ff log
access-list 3 permit aa.aa.aa.aa log
access-list 4 permit bb.bb.bb.bb log
route-map IN permit 10
!Setting up the route maps
match ip address 2
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match mpls-label
!
route-map IN permit 11
match ip address 4
!
route-map OUT permit 12
match ip address 3
!
route-map OUT permit 13
match ip address 1
set mpls-label
!
end
Route Reflector 2 Configuration Example (MPLS VPN Service Provider)
RR2 exchanges VPN-IPv4 routes with RR1 through multihop, multiprotocol eBGP. This configuration also
specifies that the next-hop information and the VPN label are preserved across the autonomous systems:
ip subnet-zero
ip cef
!
interface Loopback0
ip address bb.bb.bb.bb 255.255.255.255
!
interface Serial1/1
ip address ii.0.0.2 255.0.0.0
!
router ospf 20
log-adjacency-changes
network bb.bb.bb.bb 0.0.0.0 area 200
network ii.0.0.0 0.255.255.255 area 200
!
router bgp 200
bgp cluster-id 1
bgp log-neighbor-changes
timers bgp 10 30
neighbor aa.aa.aa.aa remote-as 100
neighbor aa.aa.aa.aa ebgp-multihop 255
neighbor aa.aa.aa.aa update-source Loopback0
neighbor ff.ff.ff.ff remote-as 200
neighbor ff.ff.ff.ff update-source Loopback0
no auto-summary
!
address-family vpnv4
neighbor aa.aa.aa.aa activate
neighbor aa.aa.aa.aa next-hop-unchanged
neighbor aa.aa.aa.aa send-community extended
neighbor ff.ff.ff.ff activate
neighbor ff.ff.ff.ff route-reflector-client
neighbor ff.ff.ff.ff send-community extended
exit-address-family
!
ip default-gateway 3.3.0.1
no ip classless
!
end
!Multihop VPNv4 session with RR1
!with next-hop-unchanged
!VPNv4 session with PE2
ASBR2 Configuration Example (MPLS VPN Service Provider)
ASBR2 exchanges IPv4 routes and MPLS labels with ASBR1. However, in contrast to ASBR1, ASBR2
does not use the RR to reflect IPv4 routes and MPLS labels to PE2. ASBR2 redistributes the IPv4 routes
and MPLS labels learned from ASBR1 into IGP. PE2 can now reach these prefixes.
ip subnet-zero
ip cef
!
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mpls label protocol ldp
!
interface Loopback0
ip address xx.xx.xx.xx 255.255.255.255
!
interface Ethernet1/0
ip address hh.0.0.1 255.0.0.0
!
interface Ethernet1/2
ip address jj.0.0.1 255.0.0.0
mpls label protocol ldp
mpls ip
!
router ospf 20
log-adjacency-changes
auto-cost reference-bandwidth 1000
redistribute connected subnets
redistribute bgp 200 subnets
! Redistributing the routes learned from
passive-interface Ethernet1/0
! ASBR1(eBGP+labels session) into IGP
network xx.xx.xx.xx 0.0.0.0 area 200
! so that PE2 will learn them
network jj..0.0 0.255.255.255 area 200
!
router bgp 200
bgp log-neighbor-changes
timers bgp 10 30
neighbor bb.bb.bb.bb remote-as 200
neighbor bb.bb.bb.bb update-source Loopback0
neighbor hh.0.0.2 remote-as 100
no auto-summary
!
address-family ipv4
redistribute ospf 20
! Redistributing IGP into BGP
neighbor hh.0.0.2 activate
! so that PE2 & RR2 loopbacks
neighbor hh.0.0.2 advertisement-interval 5
! will get into the BGP-4 table.
neighbor hh.0.0.2 route-map IN in
neighbor hh.0.0.2 route-map OUT out
neighbor hh.0.0.2 send-label
neighbor kk.0.0.2 activate
neighbor kk.0.0.2 advertisement-interval 5
neighbor kk.0.0.2 route-map IN in
neighbor kk.0.0.2 route-map OUT out
neighbor kk.0.0.2 send-label
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor bb.bb.bb.bb activate
neighbor bb.bb.bb.bb send-community extended
exit-address-family
!
ip default-gateway 3.3.0.1
ip classless
!
access-list 1 permit ff.ff.ff.ff log
!Setting up the access lists
access-list 2 permit ee.ee.ee.ee log
access-list 3 permit bb.bb.bb.bb log
access-list 4 permit aa.aa.aa.aa log
route-map IN permit 11
!Setting up the route maps
match ip address 2
match mpls-label
!
route-map IN permit 12
match ip address 4
!
route-map OUT permit 10
match ip address 1
set mpls-label
!
route-map OUT permit 13
match ip address 3
end
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Provider Examples
Route Reflector 1 Configuration Example (Non-MPLS VPN Service Provider)
Configuring MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and
MPLS Labels over a Non-MPLS VPN Service Provider Examples
Configuration examples for Inter-AS using BGP to distribute routes and MPLS labels over a non MPLS
VPN service provider included in this section are as follows:
The figure below shows two MPLS VPN service providers that are connected through a non MPLS VPN
service provider. The autonomous system in the middle of the network is configured as a backbone
autonomous system that uses LDP or Tag Distribution Protocol (TDP) to distribute MPLS labels. Traffic
engineering tunnels can also be used instead of TDP or LDP to build the LSP across the non MPLS VPN
service provider.
•
•
•
•
•
•
•
Route Reflector 1 Configuration Example (Non-MPLS VPN Service Provider), page 179
ASBR1 Configuration Example (Non-MPLS VPN Service Provider), page 180
Route Reflector 2 Configuration Example (Non-MPLS VPN Service Provider), page 182
ASBR2 Configuration Example (Non-MPLS VPN Service Provider), page 182
ASBR3 Configuration Example (Non-MPLS VPN Service Provider), page 183
Route Reflector 3 Configuration Example (Non-MPLS VPN Service Provider), page 185
ASBR4 Configuration Example (Non-MPLS VPN Service Provider), page 185
Route Reflector 1 Configuration Example (Non-MPLS VPN Service Provider)
The configuration example for RR1 specifies the following:
•
•
•
RR1 exchanges VPN-IPv4 routes with RR2 using multiprotocol, multihop eBGP.
The VPN-IPv4 next-hop information and the VPN label are preserved across the autonomous systems.
RR1 reflects to PE1:
◦
The VPN-IPv4 routes learned from RR2
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ASBR1 Configuration Example (Non-MPLS VPN Service Provider)
◦
The IPv4 routes and MPLS labels learned from ASBR1
ip subnet-zero
ip cef
!
interface Loopback0
ip address aa.aa.aa.aa 255.255.255.255
!
interface Serial1/2
ip address dd.0.0.2 255.0.0.0
clockrate 124061
!
router ospf 10
log-adjacency-changes
auto-cost reference-bandwidth 1000
network aa.aa.aa.aa 0.0.0.0 area 100
network dd.0.0.0 0.255.255.255 area 100
!
router bgp 100
bgp cluster-id 1
bgp log-neighbor-changes
timers bgp 10 30
neighbor ee.ee.ee.ee remote-as 100
neighbor ee.ee.ee.ee update-source Loopback0
neighbor ww.ww.ww.ww remote-as 100
neighbor ww.ww.ww.ww update-source Loopback0
neighbor bb.bb.bb.bb remote-as 200
neighbor bb.bb.bb.bb ebgp-multihop 255
neighbor bb.bb.bb.bb update-source Loopback0
no auto-summary
!
address-family ipv4
neighbor ee.ee.ee.ee activate
neighbor ee.ee.ee.ee route-reflector-client
neighbor ee.ee.ee.ee send-label
neighbor ww.ww.ww.ww activate
neighbor ww.ww.ww.ww route-reflector-client
neighbor ww.ww.ww.ww send-label
no neighbor bb.bb.bb.bb activate
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor ee.ee.ee.ee activate
neighbor ee.ee.ee.ee route-reflector-client
neighbor ee.ee.ee.ee send-community extended
neighbor bb.bb.bb.bb activate
neighbor bb.bb.bb.bb next-hop-unchanged
neighbor bb.bb.bb.bb send-community extended
exit-address-family
!
ip default-gateway 3.3.0.1
no ip classless
!
snmp-server engineID local 00000009020000D0584B25C0
snmp-server community public RO
snmp-server community write RW
no snmp-server ifindex persist
snmp-server packetsize 2048
!
end
!IPv4+labels session to PE1
!IPv4+labels session to ASBR1
!VPNv4 session with PE1
!MH-VPNv4 session with RR2
with next-hop-unchanged
ASBR1 Configuration Example (Non-MPLS VPN Service Provider)
ASBR1 exchanges IPv4 routes and MPLS labels with ASBR2.
In this example, ASBR1 uses route maps to filter routes:
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ASBR1 Configuration Example (Non-MPLS VPN Service Provider)
•
•
A route map called OUT specifies that ASBR1 should distribute the PE1 route (ee.ee) with labels and
the RR1 route (aa.aa) without labels.
A route map called IN specifies that ASBR1 should accept the PE2 route (ff.ff) with labels and the
RR2 route (bb.bb) without labels.
ip subnet-zero
ip cef distributed
mpls label protocol ldp
!
interface Loopback0
ip address ww.ww.ww.ww 255.255.255.255
!
interface Serial3/0/0
ip address kk.0.0.2 255.0.0.0
ip route-cache distributed
!
interface Ethernet0/3
ip address dd.0.0.1 255.0.0.0
mpls label protocol ldp
mpls ip
!
router ospf 10
log-adjacency-changes
auto-cost reference-bandwidth 1000
redistribute connected subnets
passive-interface Serial3/0/0
network ww.ww.ww.ww 0.0.0.0 area 100
network dd.0.0.0 0.255.255.255 area 100
router bgp 100
bgp log-neighbor-changes
timers bgp 10 30
neighbor aa.aa.aa.aa remote-as 100
neighbor aa.aa.aa.aa update-source Loopback0
neighbor kk.0.0.1 remote-as 200
no auto-summary
!
address-family ipv4
redistribute ospf 10
! Redistributing IGP into BGP
neighbor aa.aa.aa.aa activate
! so that PE1 & RR1 loopbacks
neighbor aa.aa.aa.aa send-label
! get into BGP table
neighbor kk.0.0.1 activate
neighbor kk.0.0.1 advertisement-interval 5
neighbor kk.0.0.1 send-label
neighbor kk.0.0.1 route-map IN in
! Accepting routes specified in route map IN
neighbor kk.0.0.1 route-map OUT out ! Distributing routes specified in route map OUT
no auto-summary
no synchronization
exit-address-family
!
ip default-gateway 3.3.0.1
ip classless
!
access-list 1 permit ee.ee.ee.ee log
access-list 2 permit ff.ff.ff.ff log
access-list 3 permit aa.aa.aa.aa log
access-list 4 permit bb.bb.bb.bb log
!
route-map IN permit 10
match ip address 2
match mpls-label
!
route-map IN permit 11
match ip address 4
!
route-map OUT permit 12
match ip address 3
!
route-map OUT permit 13
match ip address 1
set mpls-label
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Route Reflector 2 Configuration Example (Non-MPLS VPN Service Provider)
!
end
Route Reflector 2 Configuration Example (Non-MPLS VPN Service Provider)
RR2 exchanges VPN-IPv4 routes with RR1 using multihop, multiprotocol eBGP. This configuration also
specifies that the next-hop information and the VPN label are preserved across the autonomous systems:
ip subnet-zero
ip cef
!
interface Loopback0
ip address bb.bb.bb.bb 255.255.255.255
!
interface Serial1/1
ip address ii.0.0.2 255.0.0.0
!
router ospf 20
log-adjacency-changes
network bb.bb.bb.bb 0.0.0.0 area 200
network ii.0.0.0 0.255.255.255 area 200
!
router bgp 200
bgp cluster-id 1
bgp log-neighbor-changes
timers bgp 10 30
neighbor aa.aa.aa.aa remote-as 100
neighbor aa.aa.aa.aa ebgp-multihop 255
neighbor aa.aa.aa.aa update-source Loopback0
neighbor ff.ff.ff.ff remote-as 200
neighbor ff.ff.ff.ff update-source Loopback0
no auto-summary
!
address-family vpnv4
neighbor aa.aa.aa.aa activate
neighbor aa.aa.aa.aa next-hop-unchanged
neighbor aa.aa.aa.aa send-community extended
neighbor ff.ff.ff.ff activate
neighbor ff.ff.ff.ff route-reflector-client
neighbor ff.ff.ff.ff send-community extended
exit-address-family
!
ip default-gateway 3.3.0.1
no ip classless
!
end
!MH vpnv4 session with RR1
!with next-hop-unchanged
!vpnv4 session with PE2
ASBR2 Configuration Example (Non-MPLS VPN Service Provider)
ASBR2 exchanges IPv4 routes and MPLS labels with ASBR1. However, in contrast to ASBR1, ASBR2
does not use the RR to reflect IPv4 routes and MPLS labels to PE2. ASBR2 redistributes the IPv4 routes
and MPLS labels learned from ASBR1 into IGP. PE2 can now reach these prefixes.
ip subnet-zero
ip cef
!
mpls label protocol ldp
!
interface Loopback0
ip address xx.xx.xx.xx 255.255.255.255
!
interface Ethernet0/1
ip address qq.0.0.2 255.0.0.0
!
interface Ethernet1/2
ip address jj.0.0.1 255.0.0.0
mpls label protocol ldp
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ASBR3 Configuration Example (Non-MPLS VPN Service Provider)
mpls ip
!
router ospf 20
log-adjacency-changes
auto-cost reference-bandwidth 1000
redistribute connected subnets
redistribute bgp 200 subnets
!redistributing the routes learned from
passive-interface Ethernet0/1
!ASBR2 (eBGP+labels session) into IGP
network xx.xx.xx.xx 0.0.0.0 area 200
!so that PE2 will learn them
network jj.0.0.0 0.255.255.255 area 200
!
router bgp 200
bgp log-neighbor-changes
timers bgp 10 30
neighbor bb.bb.bb.bb remote-as 200
neighbor bb.bb.bb.bb update-source Loopback0
neighbor qq.0.0.1 remote-as 100
no auto-summary
!
address-family ipv4
! Redistributing IGP into
BGP
redistribute ospf 20
! so that PE2 & RR2 loopbacks
neighbor qq.0.0.1 activate
! will get into the BGP-4 table
neighbor qq.0.0.1 advertisement-interval 5
neighbor qq.0.0.1 route-map IN in
neighbor qq.0.0.1 route-map OUT out
neighbor qq.0.0.1 send-label
no auto-summary
no synchronization
exit-address-family
!
address-family vpnv4
neighbor bb.bb.bb.bb activate
neighbor bb.bb.bb.bb send-community extended
exit-address-family
!
ip default-gateway 3.3.0.1
ip classless
!
access-list 1 permit ff.ff.ff.ff log
access-list 2 permit ee.ee.ee.ee log
access-list 3 permit bb.bb.bb.bb log
access-list 4 permit aa.aa.aa.aa log
!
route-map IN permit 11
match ip address 2
match mpls-label
!
route-map IN permit 12
match ip address 4
!
route-map OUT permit 10
match ip address 1
set mpls-label
!
route-map OUT permit 13
match ip address 3
!
end
ASBR3 Configuration Example (Non-MPLS VPN Service Provider)
ASBR3 belongs to a non MPLS VPN service provider. ASBR3 exchanges IPv4 routes and MPLS labels
with ASBR1. ASBR3 also passes the routes learned from ASBR1 to ASBR4 through RR3.
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ASBR3 Configuration Example (Non-MPLS VPN Service Provider)
Note
Do not redistribute eBGP routes learned into iBGP if you are using iBGP to distribute the routes and labels.
This is not a supported configuration.
ip subnet-zero
ip cef
!
interface Loopback0
ip address yy.yy.yy.yy 255.255.255.255
interface Hssi4/0
ip address mm.0.0.0.1 255.0.0.0
mpls ip
hssi internal-clock
!
interface Serial5/0
ip address kk.0.0.1 255.0.0.0
load-interval 30
clockrate 124061
!
router ospf 30
log-adjacency-changes
auto-cost reference-bandwidth 1000
redistribute connected subnets
network yy.yy.yy.yy 0.0.0.0 area 300
network mm.0.0.0 0.255.255.255 area 300
!
router bgp 300
bgp log-neighbor-changes
timers bgp 10 30
neighbor cc.cc.cc.cc remote-as 300
neighbor cc.cc.cc.cc update-source Loopback0
neighbor kk.0.0.2 remote-as 100
no auto-summary
!
address-family ipv4
neighbor cc.cc.cc.cc activate
! iBGP+labels session with RR3
neighbor cc.cc.cc.cc send-label
neighbor kk.0.0.2 activate
! eBGP+labels session with ASBR1
neighbor kk.0.0.2 advertisement-interval 5
neighbor kk.0.0.2 send-label
neighbor kk.0.0.2 route-map IN in
neighbor kk.0.0.2 route-map OUT out
no auto-summary
no synchronization
exit-address-family
!
ip classless
!
access-list 1 permit ee.ee.ee.ee log
access-list 2 permit ff.ff.ff.ff log
access-list 3 permit aa.aa.aa.aa log
access-list 4 permit bb.bb.bb.bb log
!
route-map IN permit 10
match ip address 1
match mpls-label
!
route-map IN permit 11
match ip address 3
!
route-map OUT permit 12
match ip address 2
set mpls-label
!
route-map OUT permit 13
match ip address 4
!
ip default-gateway 3.3.0.1
ip classless
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Route Reflector 3 Configuration Example (Non-MPLS VPN Service Provider)
!
end
Route Reflector 3 Configuration Example (Non-MPLS VPN Service Provider)
RR3 is a non MPLS VPN RR that reflects IPv4 routes with MPLS labels to ASBR3 and ASBR4.
ip subnet-zero
mpls label protocol ldp
mpls traffic-eng auto-bw timers
no mpls ip
!
interface Loopback0
ip address cc.cc.cc.cc 255.255.255.255
!
interface POS0/2
ip address pp.0.0.1 255.0.0.0
crc 16
clock source internal
!
router ospf 30
log-adjacency-changes
network cc.cc.cc.cc 0.0.0.0 area 300
network pp.0.0.0 0.255.255.255 area 300
!
router bgp 300
bgp log-neighbor-changes
neighbor zz.zz.zz.zz remote-as 300
neighbor zz.zz.zz.zz update-source Loopback0
neighbor yy.yy.yy.yy remote-as 300
neighbor yy.yy.yy.yy update-source Loopback0
no auto-summary
!
address-family ipv4
neighbor zz.zz.zz.zz activate
neighbor zz.zz.zz.zz route-reflector-client
neighbor zz.zz.zz.zz send-label
neighbor yy.yy.yy.yy activate
neighbor yy.yy.yy.yy route-reflector-client
neighbor yy.yy.yy.yy send-label
no auto-summary
no synchronization
exit-address-family
!
ip default-gateway 3.3.0.1
ip classless
!
end
! iBGP+labels session with ASBR3
! iBGP+labels session with ASBR4
ASBR4 Configuration Example (Non-MPLS VPN Service Provider)
ASBR4 belongs to a non MPLS VPN service provider. ASBR4 and ASBR3 exchange IPv4 routes and
MPLS labels by means of RR3.
Note
Do not redistribute eBGP routes learned into iBGP if you are using iBGP to distribute the routes and labels.
This is not a supported configuration.
ip subnet-zero
ip cef distributed
!
interface Loopback0
ip address zz.zz.zz.zz 255.255.255.255
!
interface Ethernet0/2
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Additional References
ip address qq.0.0.1 255.0.0.0
!
interface POS1/1/0
ip address pp.0.0.2 255.0.0.0
ip route-cache distributed
!
interface Hssi2/1/1
ip address mm.0.0.2 255.0.0.0
ip route-cache distributed
mpls label protocol ldp
mpls ip
hssi internal-clock
!
router ospf 30
log-adjacency-changes
auto-cost reference-bandwidth 1000
redistribute connected subnets
passive-interface Ethernet0/2
network zz.zz.zz.zz 0.0.0.0 area 300
network pp.0.0.0 0.255.255.255 area 300
network mm.0.0.0 0.255.255.255 area 300
!
router bgp 300
bgp log-neighbor-changes
timers bgp 10 30
neighbor cc.cc.cc.cc remote-as 300
neighbor cc.cc.cc.cc update-source Loopback0
neighbor qq.0.0.2 remote-as 200
no auto-summary
!
address-family ipv4
neighbor cc.cc.cc.cc activate
neighbor cc.cc.cc.cc send-label
neighbor qq.0.0.2 activate
neighbor qq.0.0.2 advertisement-interval 5
neighbor qq.0.0.2 send-label
neighbor qq.0.0.2 route-map IN in
neighbor qq.0.0.2 route-map OUT out
no auto-summary
no synchronization
exit-address-family
!
ip classless
!
access-list 1 permit ff.ff.ff.ff log
access-list 2 permit ee.ee.ee.ee log
access-list 3 permit bb.bb.bb.bb log
access-list 4 permit aa.aa.aa.aa log
!
route-map IN permit 10
match ip address 1
match mpls-label
!
route-map IN permit 11
match ip address 3
!
route-map OUT permit 12
match ip address 2
set mpls-label
!
route-map OUT permit 13
match ip address 4
!
ip default-gateway 3.3.0.1
ip classless
!
end
Additional References
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Additional References
Related Documents
Related Topic
Document Title
MPLS
MPLS Product Literature
Standards
Standard
Title
No new or modified standards are supported by this -feature, and support for existing standards has not
been modified by this feature.
MIBs
MIB
MIBs Link
No new or modified MIBs are supported by this
feature, and support for existing MIBs has not been
modified by this feature.
To locate and download MIBs for selected
platforms, Cisco software releases, and feature sets,
use Cisco MIB Locator found at the following
URL:
http://www.cisco.com/go/mibs
RFCs
RFC
Title
RFC 1700
Assigned Numbers
RFC 1966
BGP Route Reflection: An Alternative to Full Mesh
IBGP
RFC 2842
Capabilities Advertisement with BGP-4
RFC 2858
Multiprotocol Extensions for BGP-4
RFC 3107
Carrying Label Information in BGP-4
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MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels
Feature Information for MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels
Technical Assistance
Description
Link
The Cisco Support website provides extensive
http://www.cisco.com/techsupport
online resources, including documentation and tools
for troubleshooting and resolving technical issues
with Cisco products and technologies.
To receive security and technical information about
your products, you can subscribe to various
services, such as the Product Alert Tool (accessed
from Field Notices), the Cisco Technical Services
Newsletter, and Really Simple Syndication (RSS)
Feeds.
Access to most tools on the Cisco Support website
requires a Cisco.com user ID and password.
Feature Information for MPLS VPN Inter-AS with ASBRs
Exchanging IPv4 Routes and MPLS Labels
The following table provides release information about the feature or features described in this module.
This table lists only the software release that introduced support for a given feature in a given software
release train. Unless noted otherwise, subsequent releases of that software release train also support that
feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support.
To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Table 10
Feature Information for MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels
Feature Name
Releases
Feature Configuration Information
MPLS VPN Inter-AS with
ASBRs Exchanging IPv4 Routes
and MPLS Labels
12.0(21)ST
This module explains how to
configure an MPLS VPN InterAS network so that the ASBRs
exchange IPv4 routes with MPLS
labels of the provider edge (PE)
routers. Route reflectors (RRs)
exchange VPN-IPv4 routes by
using multihop, multiprotocol,
external Border Gateway Protocol
(eBGP).
12.0(22)S
12.0(23)S
12.2(13)T
12.0(24)S
12.2(14)S
12.0(27)S
12.0(29)S
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This feature uses no new or
modified commands.
MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels
Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S.
and other countries. To view a list of Cisco trademarks, go to this URL: www.cisco.com/go/trademarks.
Third-party trademarks mentioned are the property of their respective owners. The use of the word partner
does not imply a partnership relationship between Cisco and any other company. (1110R)
Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be
actual addresses and phone numbers. Any examples, command display output, network topology diagrams,
and other figures included in the document are shown for illustrative purposes only. Any use of actual IP
addresses or phone numbers in illustrative content is unintentional and coincidental.
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Configuring MPLS VPN Inter-AS with ASBRs Exchanging IPv4 Routes and MPLS Labels over a Non-MPLS VPN Service
Provider Examples
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Load Sharing MPLS VPN Traffic
Load sharing distributes traffic so that no individual router is overburdened. In a Multiprotocol Label
Switching (MPLS) Virtual Private Network (VPN) network, you can achieve load sharing through the
following methods:
•
•
•
•
•
•
•
•
•
•
BGP multipath options
Directly connected loopback peering
Finding Feature Information, page 191
Prerequisites for Load Sharing MPLS VPN Traffic, page 191
Restrictions for Load Sharing MPLS VPN Traffic, page 191
Information About Load Sharing MPLS VPN Traffic, page 194
How to Configure Load Sharing, page 197
Configuration Examples for Load Sharing MPLS VPN Traffic, page 235
Additional References, page 237
Feature Information for Load Sharing MPLS VPN Traffic, page 239
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest feature
information and caveats, see the release notes for your platform and software release. To find information
about the features documented in this module, and to see a list of the releases in which each feature is
supported, see the Feature Information Table at the end of this document.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support.
To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Prerequisites for Load Sharing MPLS VPN Traffic
Before configuring load sharing, ensure that your MPLS VPN network (including MPLS VPN carrier
supporting carrier or interautonomous system) is configured and working properly. See the Prerequisites
for Load Sharing MPLS VPN Traffic, page 191 for references related to MPLS VPNs.
Restrictions for Load Sharing MPLS VPN Traffic
•
Configuring BGP multipath for eBGP and iBGP is only for basic MPLS Layer 3 VPNs. MPLS VPN
Inter-AS and MPLS VPN carrier supporting carrier do not support this multipath configuration.
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Load Sharing MPLS VPN Traffic
Restrictions for Load Sharing MPLS VPN Traffic
•
•
•
•
With multiple iBGP paths installed in a routing table, a route reflector advertises only one of the paths
(one next hop). If a router is behind a route reflector, all routers that are connected to multihomed sites
are not advertised unless separate VRFs with different RDs are configured for each VRF.
Each IP routing table entry for a BGP prefix that has multiple iBGP paths uses additional memory. We
recommend not using this feature on a router with a low amount of available memory and especially
when the router is carrying a full Internet routing table.
eBGP Multipath is not supported on MPLS VPN Inter-AS with ASBRs that exchange VPNv4 routes.
Load sharing using directly connected loopback peering does not apply to CSC networks that use LDP
and an IGP to distribute routes and MPLS labels.
When you configure static routes in an MPLS or MPLS VPN environment, some variations of the ip route
and ip route vrf commands are not supported. These variations of the commands are not supported in
Cisco IOS releases that support the Tag Forwarding Information Base (TFIB), specifically Cisco IOS
Releases 12.nT, 12.nM, and 12.0S. The TFIB cannot resolve prefixes when the recursive route over which
the prefixes travel disappears and then reappears. However, the command variations are supported in Cisco
IOS releases that support the MPLS Forwarding Infrastructure (MFI), specifically Cisco IOS Release
12.2(25)S and later releases. Use the following guidelines when configuring static routes.
Supported Static Routes in an MPLS Environment
The following ip route command is supported when you configure static routes in an MPLS environment:
ip route destination-prefix mask interface next-hop-address
The following ip route commands are supported when you configure static routes in an MPLS
environment and configure load sharing with static nonrecursive routes and a specific outbound interface:
ip route destination-prefix mask interface1 next-hop1
ip route destination-prefix mask interface2 next-hop2
Unsupported Static Routes in an MPLS Environment That Uses the TFIB
The following ip route command is not supported when you configure static routes in an MPLS
environment:
ip route destination-prefix mask next-hop-address
The following ip route command is not supported when you configure static routes in an MPLS VPN
environment and enable load sharing where the next hop can be reached through two paths:
ip route destination-prefix mask next-hop-address
The following ip route command is not supported when you configure static routes in an MPLS VPN
environment and enable load sharing where the destination can be reached through two next hops:
ip route destination-prefix mask next-hop1
ip route destination-prefix mask next-hop2
Use the interface and next-hop arguments when specifying static routes.
Supported Static Routes in an MPLS VPN Environment
The following ip route vrf commands are supported when you configure static routes in an MPLS VPN
environment, and the next hop and interface are associated with the same virtual routing and forwarding
(VRF) instance:
•
◦
◦
ip route vrf vrf-name destination-prefix mask next-hop-address
ip route vrf vrf-name destination-prefix mask interface next-hop-address
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Load Sharing MPLS VPN Traffic
Restrictions for Load Sharing MPLS VPN Traffic
◦
◦
ip route vrf vrf-name destination-prefix mask interface1 next-hop1
ip route vrf vrf-name destination-prefix mask interface2 next-hop2
The following ip route vrf commands are supported when you configure static routes in an MPLS VPN
environment, and the next hop is in the global table in the MPLS cloud in the global routing table. For
example, these commands are supported when the next hop is pointing to the internet gateway.
•
◦
◦
ip route vrf vrf-name destination-prefix mask next-hop-address global
ip route vrf vrf-name destination-prefix mask interface next-hop-address (This command is
supported when the next hop and the interface are in the core.)
The following ip route commands are supported when you configure static routes in an MPLS VPN
environment and enable load sharing with static nonrecursive routes and a specific outbound interfaces:
ip route destination-prefix mask interface1 next-hop1
ip route destination-prefix mask interface2 next-hop2
Unsupported Static Routes in an MPLS VPN Environment That Uses the TFIB
The following ip route command is not supported when you configure static routes in an MPLS VPN
environment, the next hop is in the global table in the MPLS cloud within the core, and you enable load
sharing where the next hop can be reached through two paths:
ip route vrf destination-prefix mask next-hop-address global
The following ip route commands are not supported when you configure static routes in an MPLS VPN
environment, the next hop is in the global table in the MPLS cloud within the core, and you enable load
sharing where the destination can be reached through two next hops:
ip route vrf destination-prefix mask next-hop1 global
ip route vrf destination-prefix mask next-hop2 global
The following ip route vrf commands are not supported when you configure static routes in an MPLS
VPN environment, and the next hop and interface are in the same VRF:
ip route vrf vrf-name destination-prefix mask next-hop1
ip route vrf vrf-name destination-prefix mask next-hop2
Supported Static Routes in an MPLS VPN Environment Where the Next Hop Resides in the Global Table on
the CE Router
The following ip route vrf command is supported when you configure static routes in an MPLS VPN
environment, and the next hop is in the global table on the customer edge (CE) side. For example, the
following command is supported when the destination-prefix is the CE router’s loopback address, as in
EBGP multihop cases.
ip route vrf vrf-name destination-prefix mask interface next-hop-address
The following ip route commands are supported when you configure static routes in an MPLS VPN
environment, the next hop is in the global table on the CE side, and you enable load sharing with static
nonrecursive routes and a specific outbound interfaces:
ip route destination-prefix mask interface1 nexthop1
ip route destination-prefix mask interface2 nexthop2
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Overview of Load Sharing Using BGP Multipath Options
Information About Load Sharing MPLS VPN Traffic
Information About Load Sharing MPLS VPN Traffic
•
•
Overview of Load Sharing Using BGP Multipath Options, page 194
Load Sharing Using Directly Connected Loopback Peering, page 196
Overview of Load Sharing Using BGP Multipath Options
A variety of Border Gateway Protocol (BGP) multipath options exist that enable you to configure load
sharing on your MPLS VPN that uses BGP.
To load share traffic at the iBGP multipath level, it is recommended that you configure BGP labeling using
the neighbor send-label command in router configuration mode. When you configure the iBGP multipath
feature, the following message is displayed as a reminder to use the neighbor send-label command
functionality:
WARNING: Using iBGP multipath feature with LDP or TE based LSPs towards the BGP nexthop,
paths taken by forwarding may not be as expected. Please consider configuring BGP
labeling (RFC 3107) for proper forwarding behavior.
The following sections describe some BGP multipath options:
•
•
•
Internal BGP Multipath Load Sharing, page 194
BGP Multipath for eBGP and iBGP, page 194
eBGP Multipath Load Sharing, page 196
Internal BGP Multipath Load Sharing
When a BGP-speaking router with no local policy configured receives multiple network layer reachability
information (NLRI) from the internal BGP (iBGP) for the same destination, the router chooses one iBGP
path as the best path. The best path is then installed in the IP routing table of the router. The iBGP
multipath feature enables the BGP-speaking router to select multiple iBGP paths as the best paths to a
destination. The best paths are then installed in the IP routing table of the router. To enable iBGP multipath
load sharing, you issue the maximum-paths ibgp command in router configuration mode. For more
information about iBGP multipath load sharing, see Configuring BGP.
BGP Multipath for eBGP and iBGP
The BGP multipath load sharing for both eBGP and iBGP in an MPLS VPN feature allows multihomed
autonomous systems and provider edge (PE) routers to be configured to distribute traffic across both
external BGP (eBGP) and iBGP paths.
BGP installs up to the maximum number of paths allowed (configured using the maximum-paths
command). BGP uses the best path algorithm to select one multipath as the best path, inserts the best path
into the routing information base (RIB), and advertises the best path to BGP peers. Other multipaths can be
inserted into the RIB, but only one path is selected as the best path.
Cisco Express Forwarding uses mutlipaths to perform load balancing on a per-packet or per-source or
destination pair basis. To enable the load sharing feature, configure the router with MPLS VPNs that
contain VPN routing and forwarding instances (VRFs) that import both eBGP and iBGP paths. You can
configure the number of multipaths separately for each VRF.
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eBGP and iBGP Multipath Load Sharing in an MPLS Network Using BGP
Note
This feature operates within the configuration parameters of the existing outbound routing policy.
•
•
eBGP and iBGP Multipath Load Sharing in an MPLS Network Using BGP, page 195
eBGP and iBGP Multipath Load Sharing with Route Reflectors, page 195
eBGP and iBGP Multipath Load Sharing in an MPLS Network Using BGP
The figure below shows an MPLS service provider network using BGP that connects two remote networks
to PE1 and PE2, which are both configured for VPNv4 unicast iBGP peering. Network 2 is a multihomed
network that is connected to PE1 and PE2. Network 2 also has extranet VPN services configured with
Network 1. Both Network 1 and Network 2 are configured for eBGP peering with the PE routers.
You can configure PE1 so that both iBGP and eBGP paths can be selected as multipaths and imported into
the VRF of Network 1. Cisco Express Forwarding uses the mutlipaths to perform load balancing. Traffic is
distributed as follows:
•
•
•
IP traffic that is sent from Network 2 to PE1 and PE2 is sent across the eBGP paths as IP traffic.
IP traffic that is sent from PE1 to PE2 is sent across the iBGP path as MPLS traffic.
MPLS traffic that is sent across an eBGP path is sent as IP traffic.
Any prefix that is advertised from Network 2 will be received by PE1 through route distinguisher (RD) 21
and RD22.
•
•
The advertisement through RD21 is carried in IP packets.
The advertisement through RD22 is carried in MPLS packets.
Both paths can be selected as multipaths for VRF1 and inserted into the VRF1 RIB.
eBGP and iBGP Multipath Load Sharing with Route Reflectors
The figure below shows a topology that contains three PE routers and a route reflector, all configured for
iBGP peering. PE2 and PE3 each advertise an equal preference eBGP path to PE1. By default, the route
reflector chooses only one path and advertises PE1.
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eBGP Multipath Load Sharing
For all equal preference paths to PE1 to be advertised through the route reflector, you must configure each
VRF with a different RD. The prefixes received by the route reflector are recognized differently and
advertised to PE1.
eBGP Multipath Load Sharing
When a router learns two identical eBGP paths for a prefix from a neighboring autonomous system, it
chooses the path with the lower route ID as the best path. This best path is installed in the IP routing table.
You can enable eBGP multipath, which installs multiple paths in the IP routing table when the eBGP paths
are learned from a neighboring autonomous system, instead of picking one best path.
During packet switching, depending on the switching mode, either per-packet or per-destination load
sharing is performed among the multiple paths. The maximum-paths router configuration command
controls the number of paths allowed. By default, BGP installs only one path to the IP routing table.
Load Sharing Using Directly Connected Loopback Peering
You use this feature with MPLS VPN Inter-AS and MPLS VPN carrier supporting carrier (CSC) networks
to load share traffic between adjacent label switched routers (LSRs) that are connected by multiple links.
The LSRs could be a pair of autonomous system boundary routers (ASBRs) or a CSC-PE and a CSC-CE.
Using directly connected loopback peering allows load sharing at the IGP level, so more than one BGP
session is not needed between the LSRs. No other label distribution mechanism is needed between the
adjacent LSRs than BGP.
Directly connected loopback peering enables load sharing of traffic as follows:
•
•
•
•
•
A BGP session is established, using the loopback addresses of the LSRs.
MPLS is enabled on the connecting links.
Multiple static routes to the loopback address of the adjacent LSR allow IGP load sharing.
The outgoing label to the loopback address of the adjacent LSR is an implicit null label and is inferred
by the LSR.
Because IGP load sharing is enabled on the loopback address of the adjacent LSR, any traffic destined
to a prefix that is learned over the BGP session (and recurses over the loopback) is load shared.
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How to Configure Load Sharing
How to Configure Load Sharing
• Configuring BGP Multipath Load Sharing for eBGP and iBGP, page 197
• Verifying BGP Multipath Load Sharing for eBGP and iBGP, page 198
• Configuring eBGP Multipath Load Sharing with MPLS VPN Inter-AS, page 199
• Configuring eBGP Multipath Load Sharing with MPLS VPN Carrier Supporting Carrier on the CSCPE Routers, page 201
• Configuring eBGP Multipath Load Sharing with MPLS VPN Carrier Supporting Carrier on the CSCCE Routers, page 203
• Configuring DCLP for MPLS VPN Inter-AS using ASBRs to Exchange VPN-IPv4 Addresses, page
206
• Configuring DCLP for MPLS VPN Inter-AS Using ASBRs to Exchange IPv4 Routes and Labels,
page 213
• Configuring Directly Connected Loopback Peering on MPLS VPN Carrier Supporting Carrier, page
221
Configuring BGP Multipath Load Sharing for eBGP and iBGP
To configure iBGP and eBGP routes for multipath load sharing, perform the following task.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. address-family ipv4 [multicast | unicast | vrf vrf-name]
5. maximum-paths eibgp number-of-paths
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
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Verifying BGP Multipath Load Sharing for eBGP and iBGP
How to Configure Load Sharing
Command or Action
Step 3 router bgp as-number
Purpose
Enters router configuration mode and configures the router to run a
BGP routing process.
Example:
Router(config)# router bgp 1
Step 4 address-family ipv4 [multicast | unicast | vrf
vrf-name]
Enters address family configuration mode for configuring routing
sessions such as BGP that use standard IPv4 address prefixes.
Note For this task you must create the VRF and specify the vrf
keyword.
Example:
Router(config-router)# address-family
ipv4 vrf vrf1
Step 5 maximum-paths eibgp number-of-paths
•
•
•
The multicast keyword specifies IPv4 multicast address prefixes.
The unicast keyword specifies IPv4 unicast address prefixes.
The vrf vrf-name keyword and argument specify the name of the
VRF to associate with subsequent IPv4 address family
configuration mode commands.
Configures the number of parallel iBGP and eBGP routes that can be
installed into a routing table.
Example:
Router(config-router-af)# maximum-paths
eibgp 6
Verifying BGP Multipath Load Sharing for eBGP and iBGP
To verify the configuration of iBGP and eBGP routes for multipath load sharing, perform this task.
SUMMARY STEPS
1. enable
2. show ip bgp vpnv4 {all | rd route-distinguisher | vrf vrf-name} | [rib-failure] [ip-prefix/length
[longer-prefixes]] [network-address [mask] [longer-prefixes]] [cidr-only] [community] [communitylist] [dampened-paths] [filter-list] [flap-statistics] [inconsistent-as] [neighbors] [paths [line]] [peergroup] [quote-regexp] [regexp] [summary] [labels]
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
(Optional) Enables privileged EXEC mode.
•
Example:
Router> enable
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Enter your password if prompted.
Configuring eBGP Multipath Load Sharing with MPLS VPN Inter-AS
How to Configure Load Sharing
Command or Action
Purpose
Step 2 show ip bgp vpnv4 {all | rd route-distinguisher | vrf vrf-name} | [ribfailure] [ip-prefix/length [longer-prefixes]] [network-address [mask]
[longer-prefixes]] [cidr-only] [community] [community-list]
[dampened-paths] [filter-list] [flap-statistics] [inconsistent-as]
[neighbors] [paths [line]] [peer-group] [quote-regexp] [regexp]
[summary] [labels]
Displays attributes and multipaths for a
specific network in an MPLS VPN.
•
Enter one or more keywords or
arguments.
Example:
Router# show ip bgp vpnv4 all
Configuring eBGP Multipath Load Sharing with MPLS VPN Inter-AS
Perform this task on the ASBRs to configure eBGP Multipath for MPLS VPN interautonomous systems
with ASBRs exchanging IPv4 routes and MPLS labels.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. neighbor {ip-address | peer-group-name} remote-as as-number
5. address-family ipv4 [multicast | unicast | vrf vrf-name]
6. maximum-paths number-paths
7. neighbor {ip-address | peer-group-name} activate
8. neighbor ip-address send-label
9. exit-address-family
10. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
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Command or Action
Step 3 router bgp as-number
Example:
Purpose
Configures a BGP routing process and places the router in router
configuration mode.
•
Router(config)# router bgp 100
Step 4 neighbor {ip-address | peer-group-name}
remote-as as-number
Example:
Adds an entry to the BGP or multiprotocol BGP neighbor table.
•
•
•
Router(config-router)# neighbor
10.0.0.1 remote-as 200
Step 5 address-family ipv4 [multicast | unicast |
vrf vrf-name]
Example:
Example:
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
The as-number argument specifies the autonomous system to which
the neighbor belongs.
Enters address family configuration mode for configuring routing sessions
such as BGP that use standard IPv4 address prefixes.
•
•
•
Router(config-router)# addressfamily ipv4
Step 6 maximum-paths number-paths
The as-number argument indicates the number of an autonomous
system that identifies the router to other BGP routers and tags the
routing information passed along. Valid numbers are from 0 to 65535.
Private autonomous system numbers that can be used in internal
networks range from 64512 to 65535.
The multicast keyword specifies IPv4 multicast address prefixes.
The unicast keyword specifies IPv4 unicast address prefixes.
The vrf vrf-name keyword and argument specify the name of the VRF
to associate with subsequent IPv4 address family configuration mode
commands.
(Optional) Controls the maximum number of parallel routes an IP routing
protocol can support.
•
The number-paths argument specifies the maximum number of
parallel routes an IP routing protocol installs in a routing table.
Router(config-router-af)# maximumpaths 2
Step 7 neighbor {ip-address | peer-group-name}
activate
Enables the exchange of information with a neighboring router.
•
•
Example:
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
Router(config-router-af)# neighbor
10.0.0.1 activate
Step 8 neighbor ip-address send-label
Example:
Enables a BGP router to send MPLS labels with BGP routes to a
neighboring BGP router.
•
The ip-address argument specifies the IP address of the neighboring
router.
Router(config-router-af)# neighbor
10.0.0.1 send-label
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How to Configure Load Sharing
Command or Action
Step 9 exit-address-family
Purpose
Exits address family configuration mode.
Example:
Router(config-router-af)# exitaddress-family
Step 10 end
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-router-af)# end
Configuring eBGP Multipath Load Sharing with MPLS VPN Carrier
Supporting Carrier on the CSC-PE Routers
Perform this task to configure eBGP Multipath load sharing on the CSC-PE routers that distribute BGP
routes with MPLS labels.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. address-family ipv4 [multicast | unicast | vrf vrf-name]
5. maximum-paths number-paths
6. neighbor {ip-address | peer-group-name} remote-as as-number
7. neighbor {ip-address | peer-group-name} activate
8. neighbor ip-address as-override
9. neighbor ip-address send-label
10. exit-address-family
11. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
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Command or Action
Step 2 configure terminal
Purpose
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Configures a BGP routing process and enters router configuration mode.
•
Example:
Router(config)# router bgp 100
The as-number argument indicates the number of an autonomous
system that identifies the router to other BGP routers and tags the
routing information passed along. Valid numbers are from 0 to 65535.
Private autonomous system numbers that can be used in internal
networks range from 64512 to 65535.
Step 4 address-family ipv4 [multicast | unicast | Specifies the IPv4 address family type and enters address family
configuration mode.
vrf vrf-name]
Example:
•
•
•
Router(config-router)# addressfamily ipv4 vrf vpn1
Step 5 maximum-paths number-paths
(Optional) Controls the maximum number of parallel routes an IP routing
protocol can support.
Example:
•
Router(config-router-af)# maximumpaths 2
•
Step 6 neighbor {ip-address | peer-group-name}
remote-as as-number
Example:
Example:
On the CSC-PE router, this command is enabled in address family
configuration mode.
The number-paths argument specifies the maximum number of
parallel routes an IP routing protocol installs in a routing table.
Adds an entry to the BGP or multiprotocol BGP neighbor table.
•
•
•
Router(config-router-af)# neighbor
10.0.0.1 remote-as 200
Step 7 neighbor {ip-address | peer-group-name}
activate
The multicast keyword specifies IPv4 multicast address prefixes.
The unicast keyword specifies IPv4 unicast address prefixes.
The vrf vrf-name keyword and argument specify the name of the VRF
to associate with subsequent IPv4 address family configuration mode
commands.
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
The as-number argument specifies the autonomous system to which
the neighbor belongs.
Enables the exchange of information with a neighboring BGP router.
•
•
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer
group.
Router(config-router-af)# neighbor
10.0.0.1 activate
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How to Configure Load Sharing
Command or Action
Step 8 neighbor ip-address as-override
Purpose
Configures a PE router to override the autonomous system number (ASN)
of a site with the ASN of a provider.
•
Example:
The ip-address argument specifies the IP address of the router that is
to be overridden with the ASN provided.
Router(config-router-af)# neighbor
10.0.0.1 as-override
Step 9 neighbor ip-address send-label
Enables a BGP router to send MPLS labels with BGP routes to a
neighboring BGP router.
•
Example:
The ip-address argument specifies the IP address of the neighboring
router.
Router(config-router-af)# neighbor
10.0.0.1 send-label
Step 10 exit-address-family
Exits address family configuration mode.
Example:
Router(config-router-af)# exitaddress-family
Step 11 end
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-router)# end
Configuring eBGP Multipath Load Sharing with MPLS VPN Carrier
Supporting Carrier on the CSC-CE Routers
Perform this task to configure eBGP Multipath load sharing on the CSC-CE routers.
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How to Configure Load Sharing
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. maximum-paths number-paths
5. address-family ipv4 [multicast | unicast | vrf vrf-name]
6. redistribute protocol
7. neighbor {ip-address | peer-group-name} remote-as as-number
8. neighbor {ip-address | peer-group-name} activate
9. neighbor ip-address send-label
10. exit-address-family
11. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Configures a BGP routing process and enters router configuration mode.
•
Example:
Router(config)# router bgp 200
Step 4 maximum-paths number-paths
The as-number argument indicates the number of an autonomous system
that identifies the router to other BGP routers and tags the routing
information passed along. Valid numbers are from 0 to 65535. Private
autonomous system numbers that can be used in internal networks range
from 64512 to 65535.
(Optional) Controls the maximum number of parallel routes an IP routing
protocol can support.
Example:
•
Router(config-router)# maximumpaths 2
•
On the CSC-CE routers, this command is issued in router configuration
mode.
The number-paths argument specifies the maximum number of parallel
routes an IP routing protocol installs in a routing table.
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Command or Action
Step 5 address-family ipv4 [multicast |
unicast | vrf vrf-name]
Example:
Purpose
Specifies the IPv4 address family type and enters address family configuration
mode.
•
•
•
Router(config-router)# addressfamily ipv4
Step 6 redistribute protocol
The multicast keyword specifies IPv4 multicast address prefixes.
The unicast keyword specifies IPv4 unicast address prefixes.
The vrf vrf-name keyword and argument specify the name of the VRF to
associate with subsequent IPv4 address family configuration mode
commands.
Redistributes routes from one routing domain into another routing domain.
•
Example:
Router(config-router-af)#
redistribute static
The protocol argument specifies the source protocol from which routes are
being redistributed. It can be one of the following keywords: bgp,
connected, egp, igrp, isis, mobile, ospf, rip, and static [ip].
◦
The static [ip] keyword redistributes IP static routes.
Note The optional ip keyword is used when you redistribute static routes into
Intermediate System- to-Intermediate System (IS-IS).
•
◦
◦
Step 7 neighbor {ip-address | peer-groupname} remote-as as-number
Example:
The connected keyword refers to routes that are established
automatically when IP is enabled on an interface.
For routing protocols such as Open Shortest Path First (OSPF) and ISIS, these routes are redistributed as external to the autonomous system.
Adds an entry to the BGP or multiprotocol BGP neighbor table.
•
•
•
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer group.
The as-number argument specifies the autonomous system to which the
neighbor belongs.
Router(config-router-af)#
neighbor 10.0.0.2 remote-as 100
Step 8 neighbor {ip-address | peer-groupname} activate
Enables the exchange of information with a neighboring BGP router.
•
•
The ip-address argument specifies the IP address of the neighbor.
The peer-group-name argument specifies the name of a BGP peer group.
Example:
Router(config-router-af)#
neighbor 10.0.0.2 activate
Step 9 neighbor ip-address send-label
Example:
Enables a BGP router to send MPLS labels with BGP routes to a neighboring
BGP router.
•
The ip-address argument specifies the IP address of the neighboring router.
Router(config-router-af)#
neighbor 10.0.0.2 send-label
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Configuring Loopback Interface Addresses for Directly Connected ASBRs
Command or Action
Purpose
Step 10 exit-address-family
Exits address family configuration mode.
Example:
Router(config-router-af)# exitaddress-family
Step 11 end
(Optional) Exits to privileged EXEC mode.
Example:
Router(config-router)# end
Configuring DCLP for MPLS VPN Inter-AS using ASBRs to Exchange VPNIPv4 Addresses
This section describes the following tasks you need to do to configure peering of loopback interfaces of
directly connected ASBRs:
The figure below shows the loopback configuration for directly connected ASBR1 and ASBR2. This
configuration is used as the example in the tasks that follow.
Figure 22
•
•
•
•
•
Loopback Interface Configuration for Directly Connected ASBR1 and ASBR2
Configuring Loopback Interface Addresses for Directly Connected ASBRs, page 206
Configuring 32 Static Routes to the eBGP Neighbor Loopback, page 207
Configuring Forwarding on Connecting Loopback Interfaces, page 209
Configuring an eBGP Session Between the Loopbacks, page 210
Verifying That Load Sharing Occurs Between Loopbacks, page 213
Configuring Loopback Interface Addresses for Directly Connected ASBRs
Perform this task to configure loopback interface addresses for directly connected ASBRs.
Note
Loopback addresses need to be configured for each directly connected ASBR. That is, configure a loopback
address for ASBR1 and for ASBR2 in the example shown in the figure above.
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Configuring 32 Static Routes to the eBGP Neighbor Loopback
SUMMARY STEPS
1. enable
2. configure terminal
3. interface loopback interface- number
4. ip address ip-address mask [secondary]
5. end
DETAILED STEPS
Command or Action
Purpose
Step 1 enable
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 interface loopback interface- number
Configures a software-only virtual interface that emulates an interface that is
always up and enters interface configuration mode.
•
Example:
Router(config)# interface loopback 0
Step 4 ip address ip-address mask [secondary]
Sets a primary or secondary IP address for an interface.
•
•
•
Example:
Router(config-if)# ip address
10.10.10.10 255.255.255.255
Step 5 end
The interface-number argument is the number of the loopback
interface that you want to create or configure. There is no limit on the
number of loopback interfaces that you can create.
The ip-address argument is the IP address.
The mask argument is the mask for the associated IP subnet.
The secondary keyword specifies that the configured address is a
secondary IP address. If this keyword is omitted, the configured address
is the primary IP address.
Exits to privileged EXEC mode.
Example:
Router(config-if)# end
Configuring 32 Static Routes to the eBGP Neighbor Loopback
Perform this task to configure /32 static routes to the eBGP neighbor loopback.
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Configuring 32 Static Routes to the eBGP Neighbor Loopback
Note
You need to configure /32 static routes on each of the directly connected ASBRs.
SUMMARY STEPS
1. enable
2. configure terminal
3. ip route prefix mask {ip-address | interface-type interface-number [ip-address]} [distance] [name]
[permanent] [tag tag]
4. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 ip route prefix mask {ip-address |
interface-type interface-number [ipaddress]} [distance] [name]
[permanent] [tag tag]
Establishes static routes.
•
•
•
Example:
•
Router(config)# ip route
10.20.20.20 255.255.255.255
Ethernet 1/0 172.16.0.1
•
•
•
•
Step 4 end
The prefix argument is the IP route prefix for the destination.
The mask argument is the prefix mask for the destination.
The ip-address argument is the IP address of the next hop that you can use
to reach the specified network.
The interface-type and interface-number arguments are the network
interface type and interface number.
The distance argument is an administrative distance.
The name argument applies a name to the specified route.
The permanent keyword specifies that the route is not to be removed,
even if the interface shuts down.
The tag tag keyword and argument name a tag value that can be used as a
“match” value for controlling redistribution through the use of route maps.
Exits to privileged EXEC mode.
Example:
Router(config)# end
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Configuring Forwarding on Connecting Loopback Interfaces
Perform this task to configure forwarding on the connecting loopback interfaces.
This task is required for sessions between loopbacks. In the Configuring 32 Static Routes to the eBGP
Neighbor Loopback, page 207 task, Ethernet 1/0 and Ethernet 0/0 are the connecting interfaces.
SUMMARY STEPS
1. enable
2. configure terminal
3. interface type slot/port
4. mpls bgp forwarding
5. exit
6. Repeat Steps 3 and 4 for another connecting interface (Ethernet 0/0).
7. end
DETAILED STEPS
Command or Action
Purpose
Step 1 enable
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 interface type slot/port
Configures an interface type and enters interface configuration
mode.
•
•
Example:
Router(config)# interface ethernet 1/0
•
Step 4 mpls bgp forwarding
The type argument is the type of interface to be configured.
The slot argument is the slot number. Refer to the appropriate
hardware manual for slot and port information.
The /port argument is the port number. Refer to the
appropriate hardware manual for slot and port information.
Configures BGP to enable MPLS forwarding on connecting
interfaces.
Example:
Router(config-if)# mpls bgp forwarding
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Command or Action
Step 5 exit
Purpose
Exits to global configuration mode.
Example:
Router(config-if)# exit
Step 6 Repeat Steps 3 and 4 for another connecting interface
(Ethernet 0/0).
Step 7 end
Exits to privileged EXEC mode.
Example:
Router(config)# end
Configuring an eBGP Session Between the Loopbacks
Perform this task to configure an eBGP session between the loopbacks.
Note
You need to configure an eBGP session between loopbacks on each directly connected ASBR.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. no bgp default route-target filter
5. neighbor {ip-address | peer-group-name} remote-as as-number
6. neighbor {ip-address | peer-group-name} disable-connected-check
7. neighbor {ip-address | ipv6-address | peer-group-name} update-source interface-type interfacenumber
8. address-family vpnv4 [unicast]
9. neighbor {ip-address | peer-group-name | ipv6-address} activate
10. neighbor {ip-address | peer-group-name} send-community [both | standard extended]
11. end
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DETAILED STEPS
Command or Action
Purpose
Step 1 enable
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Configures the BGP routing process.
•
Example:
The as-number indicates the number of an autonomous system that
identifies the router to other BGP routers and tags the routing
information passed along.
Router(config)# router bgp 200
Step 4 no bgp default route-target filter
Disables BGP route-target filtering, and enters router configuration mode.
•
All received BGP VPN-IPv4 routes are accepted by the router.
Example:
Router(config)# no bgp default
route-target filter
Step 5 neighbor {ip-address | peer-group-name} Adds an entry to the BGP or multiprotocol BGP neighbor table.
remote-as as-number
• The ip-address argument is the IP address of the neighbor.
• The peer-group-name argument is the name of a BGP peer group.
• The as-number argument is the autonomous system to which the
Example:
neighbor belongs.
Router(config-router)# neighbor
10.20.20.20 remote-as 100
Step 6 neighbor {ip-address | peer-group-name} Allows peering between loopbacks.
disable-connected-check
• The ip-address argument is the IP address of the neighbor.
• The peer-group-name argument is the name of a BGP peer group.
Example:
Router(config-router)# neighbor
10.20.20.20 disable-connected-check
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Command or Action
Step 7 neighbor {ip-address | ipv6-address |
peer-group-name} update-source
interface-type interface-number
Purpose
Allows BGP sessions to use any operational interface for TCP connections.
•
•
Example:
Router(config-router)# neighbor
10.20.20.20 update-source Loopback 0
This argument must be in the form documented in RFC 2373, where the
address is specified in hexadecimal using 16-bit values between colons.
•
•
•
Step 8 address-family vpnv4 [unicast]
Example:
The ip-address argument is the IPv4 address of the BGP-speaking
neighbor.
The ipv6-address argument is the IPv6 address of the BGP-speaking
neighbor.
The peer-group-name argument is the name of a BGP peer group.
The interface-type argument is the interface type.
The interface-number argument is the interface number.
Enters address family configuration mode for configuring routing protocols
such as BGP, Routing Information Protocol (RIP), and static routing.
•
The unicast keyword specifies unicast prefixes.
Router(config-router)# addressfamily vpnv4
Step 9 neighbor {ip-address | peer-group-name | Enables the exchange of information with a BGP neighbor.
ipv6-address} activate
• The ip-address argument is the IP address of the neighboring router.
• The peer-group-name argument is the name of a BGP peer group.
• The ipv6-address argument is the IPv6 address of the BGP-speaking
Example:
neighbor.
Router(config-router-af)# neighbor
10.20.20.20 activate
Note This argument must be in the form documented in RFC 2373, where
the address is specified in hexadecimal using 16-bit values between
colons.
Step 10 neighbor {ip-address | peer-group-name} Specifies that a communities attribute should be sent to a BGP neighbor.
send-community [both | standard
• The ip-address argument is the IP address of the neighboring router.
extended]
• The peer-group-name argument is the name of a BGP peer group.
• The both keyword specifies that both standard and extended
communities will be sent.
Example:
• The standard keyword specifies that only standard communities will
Router(config-router-af)# neighbor
be sent.
10.20.20.20 send-community extended
• The extended keyword specifies that only extended communities will
be sent.
Step 11 end
Exits to privileged EXEC mode.
Example:
Router(config)# end
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Verifying That Load Sharing Occurs Between Loopbacks
Verifying That Load Sharing Occurs Between Loopbacks
Perform this task to verify that load sharing occurs between loopbacks. You need to ensure that the MPLS
Label Forwarding Information Base (LFIB) entry for the neighbor route lists the available paths and
interfaces.
SUMMARY STEPS
1. enable
2. show mpls forwarding-table {mask | length} | labels label [network label] | interface interface | nexthop address | lsp-tunnel [tunnel-id]] [vrf vrf-name] [detail]
3. disable
DETAILED STEPS
Command or Action
Purpose
Step 1 enable
(Optional) Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 show mpls forwarding-table {mask | length} | labels label [network Displays the contents of the MPLS LFIB.
label] | interface interface | next-hop address | lsp-tunnel [tunnel• Enter an optional keyword or argument if
id]] [vrf vrf-name] [detail]
desired.
Example:
Router# show mpls forwarding-table
Step 3 disable
Exits to user EXEC mode.
Example:
Router# disable
Configuring DCLP for MPLS VPN Inter-AS Using ASBRs to Exchange IPv4
Routes and Labels
The following sections describe how to configure peering of loopback interfaces of directly connected
ASBRs to achieve load sharing in an interautonomous system network:
The figure below shows the loopback configuration for directly connected ASBR1 and ASBR2. This
configuration is used as the example in the tasks that follow.
Figure 23
Loopback Interface Configuration for Directly Connected ASBR1 and ASBR2
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•
•
•
•
•
Configuring Loopback Interface Addresses for Directly Connected ASBRs, page 214
Configuring 32 Static Routes to the eBGP Neighbor Loopback, page 215
Configuring Forwarding on Connecting Loopback Interfaces, page 216
Configuring an eBGP Session Between the Loopbacks, page 217
Verifying That Load Sharing Occurs Between Loopbacks, page 220
Configuring Loopback Interface Addresses for Directly Connected ASBRs
Perform this task to configure loopback interface addresses.
Note
Loopback addresses need to be configured for each directly connected ASBR. That is, configure a loopback
address for ASBR1 and for ASBR2 as in the example shown in the figure above.
SUMMARY STEPS
1. enable
2. configure terminal
3. interface loopback interface number
4. ip address ip-address [mask [secondary]]
5. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 interface loopback interface number
Example:
Router(config)# interface loopback 0
Configures a software-only virtual interface that emulates an interface that is
always up and enters interface configuration mode.
•
The interface-number argument is the number of the loopback interface
that you want to create or configure. There is no limit on the number of
loopback interfaces that you can create.
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Command or Action
Purpose
Step 4 ip address ip-address [mask [secondary]]
Sets a primary or secondary IP address for an interface.
•
•
•
Example:
Router(config-if)# ip address
10.10.10.10 255.255.255.255
Step 5 end
The ip-address argument is the IP address.
The mask argument is the mask for the associated IP subnet.
The secondary keyword specifies that the configured address is a
secondary IP address. If this keyword is omitted, the configured address
is the primary IP address.
Exits to privileged EXEC mode.
Example:
Router(config-if)# end
Configuring 32 Static Routes to the eBGP Neighbor Loopback
Perform this task to configure /32 static routes to the eBGP neighbor loopback.
Note
You need to configure /32 static routes on each of the directly connected ASBRs.
SUMMARY STEPS
1. enable
2. configure terminal
3. ip route prefix mask {ip-address | interface-type interface-number [ip-address]} [distance] [name]
[permanent] [tag tag]
4. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
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Command or Action
Step 3 ip route prefix mask {ip-address |
interface-type interface-number [ipaddress]} [distance] [name]
[permanent] [tag tag]
Purpose
Establishes static routes.
•
•
•
Example:
•
Router(config)# ip route
10.20.20.20 255.255.255.255
Ethernet 1/0 172.16.0.1
•
•
•
•
Step 4 end
The prefix argument is the IP route prefix for the destination.
The mask argument is the prefix mask for the destination.
The ip-address argument is the IP address of the next hop that you can use
to reach the specified network.
The interface-type and interface-number arguments are the network
interface type and interface number.
The distance argument is an administrative distance.
The name argument applies a name to the specified route.
The permanent keyword specifies that the route is not to be removed,
even if the interface shuts down.
The tag tag keyword and argument name a tag value that can be used as a
“match” value for controlling redistribution through the use of route maps.
Exits to privileged EXEC mode.
Example:
Router(config)# end
Configuring Forwarding on Connecting Loopback Interfaces
Perform this task to configure forwarding on the connecting loopback interfaces.
This task is required for sessions between loopbacks. In the Configuring 32 Static Routes to the eBGP
Neighbor Loopback, page 215 task, Ethernet1/0 and Ethernet0/0 are the connecting interfaces.
SUMMARY STEPS
1. enable
2. configure terminal
3. interface type slot/port
4. mpls bgp forwarding
5. exit
6. Repeat Steps 3 and 4 for another connecting interface (Ethernet 0/0).
7. end
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DETAILED STEPS
Command or Action
Purpose
Step 1 enable
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 interface type slot/port
Configures an interface type and enters interface configuration
mode.
•
•
Example:
Router(config)# interface ethernet 1/0
•
Step 4 mpls bgp forwarding
The type argument is the type of interface to be configured.
The slot argument is the slot number. Refer to the appropriate
hardware manual for slot and port information.
The /port argument is the port number. Refer to the
appropriate hardware manual for slot and port information.
Configures BGP to enable MPLS forwarding on connecting
interfaces.
Example:
Router(config-if)# mpls bgp forwarding
Step 5 exit
Exits to global configuration mode.
Example:
Router(config-if)# exit
Step 6 Repeat Steps 3 and 4 for another connecting interface
(Ethernet 0/0).
Step 7 end
Exits to privileged EXEC mode.
Example:
Router(config)# end
Configuring an eBGP Session Between the Loopbacks
Perform the following tasks to configure an eBGP session between the loopbacks.
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Note
You need to configure an eBGP session between loopbacks on each directly connected ASBR.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. bgp log-neighbor-changes
5. neighbor {ip-address | peer-group-name} remote-as as-number
6. neighbor {ip-address | peer-group-name} disable-connected-check
7. neighbor {ip-address | ipv6-address | peer-group-name} update-source interface-type interfacenumber
8. address-family ipv4 [unicast] vrf vrf-name
9. neighbor {ip-address | peer-group-name | ipv6-address} activate
10. neighbor {ip-address | peer-group-name} send-community [both | standard | extended
11. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Configures the BGP routing process, and enters router configuration mode.
•
Example:
The as-number argument indicates the number of an autonomous
system that identifies the router to other BGP routers and tags the
routing information passed along.
Router(config)# router bgp 200
Step 4 bgp log-neighbor-changes
Enables logging of BGP neighbor resets.
Example:
Router(config-router)# bgp logneighbor-changes
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Command or Action
Purpose
Step 5 neighbor {ip-address | peer-group-name} Adds an entry to the BGP or multiprotocol BGP neighbor table.
remote-as as-number
• The ip-address argument is the IP address of the neighbor.
• The peer-group-name argument is the name of a BGP peer group.
• The as-number argument is the number of the autonomous system to
Example:
which the neighbor belongs.
Router(config-router)# neighbor
10.20.20.20 remote-as 100
Step 6 neighbor {ip-address | peer-group-name} Allows peering between loopbacks.
disable-connected-check
• The ip-address argument is the IP address of the neighbor.
• The peer-group-name argument is the name of a BGP peer group.
Example:
Router(config-router)# neighbor
10.20.20.20 disable-connected-check
Step 7 neighbor {ip-address | ipv6-address |
peer-group-name} update-source
interface-type interface-number
Allows BGP sessions to use any operational interface for TCP connections.
•
•
Example:
Router(config-router)# neighbor
10.20.20.20 update-source Loopback 0
Note This argument must be in the form documented in RFC 2373, where
the address is specified in hexadecimal using 16-bit values between
colons.
•
•
•
Step 8 address-family ipv4 [unicast] vrf vrfname
Example:
Router(config-router)# addressfamily ipv4
The ip-address argument is the IPv4 address of the BGP-speaking
neighbor.
The ipv6-address argument is the IPv6 address of the BGP-speaking
neighbor.
The peer-group-name argument is the name of a BGP peer group.
The interface-type argument is the interface type.
The interface-number argument is the interface number.
Enters address family configuration mode for configuring routing protocols
such as BGP, Routing Information Protocol (RIP), and static routing.
•
•
The unicast keyword specifies unicast prefixes.
The vrf vrf-name keyword and argument specify the name of a VPN
routing/forwarding instance (VRF) to associate with submode
commands.
Step 9 neighbor {ip-address | peer-group-name | Enables the exchange of information with a BGP neighbor.
ipv6-address} activate
• The ip-address argument is the IP address of the neighboring router.
• The peer-group-name argument is the name of the BGP peer group.
•
The ipv6-address argument is the IPv6 address of the BGP-speaking
Example:
neighbor.
Router(config-router-af)# neighbor
10.20.20.20 activate
Note This argument must be in the form documented in RFC 2373, where
the address is specified in hexadecimal using 16-bit values between
colons.
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Command or Action
Purpose
Step 10 neighbor {ip-address | peer-group-name} Specifies that a communities attribute should be sent to a BGP neighbor.
send-community [both | standard |
• The ip-address argument is the IP address of the neighboring router.
extended
• The peer-group-name argument is the name of the BGP peer group.
• The both keyword specifies that both standard and extended
communities will be sent.
Example:
• The standard keyword specifies that only standard communities will
Router(config-router-af)# neighbor
be sent.
10.20.20.20 send-community extended
• The extended keyword specifies that only extended communities will
be sent.
Step 11 end
Exits to privileged EXEC mode.
Example:
Router(config)# end
Verifying That Load Sharing Occurs Between Loopbacks
To verify that load sharing can occur between loopbacks, ensure that the MPLS LFIB entry for the
neighbor route lists the available paths and interfaces.
SUMMARY STEPS
1. enable
2. show mpls forwarding-table [network {mask |length} | labels label [label] | interface interface | nexthop address | lsp-tunnel [tunnel-id]] [vrf vrf-name] [detail]
3. disable
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 show mpls forwarding-table [network {mask |length} | labels label [label] Displays the contents of the MPLS LFIB.
| interface interface | next-hop address | lsp-tunnel [tunnel-id]] [vrf vrf• Enter a keyword or argument, if desired.
name] [detail]
Example:
Router# show mpls forwarding-table
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Configuring Loopback Interface Addresses on CSC-PE Routers
Command or Action
Purpose
Step 3 disable
Exits to user EXEC mode.
Example:
Router# disable
Configuring Directly Connected Loopback Peering on MPLS VPN Carrier
Supporting Carrier
The following sections explain how to load balance CSC traffic by peering loopback interfaces of directly
connected CSC-PE and CSC-CE routers:
The figure below shows the loopback configuration for directly connected CSC-PE and CSC-CE routers.
This configuration is used as the example in the tasks that follow.
Figure 24
•
•
•
•
•
•
•
•
•
Loopback Interface Configuration for Directly Connected CSC-PE and CSC-CE Routers
Configuring Loopback Interface Addresses on CSC-PE Routers, page 221
Configuring Loopback Interface Addresses for CSC-CE Routers, page 223
Configuring 32 Static Routes to the eBGP Neighbor Loopback on the CSC-PE Router, page 224
Configuring 32 Static Routes to the eBGP Neighbor Loopback on the CSC-CE Router, page 225
Configuring Forwarding on CSC-PE Interfaces That Connect to the CSC-CE Loopback, page 226
Configuring Forwarding on CSC-CE Interfaces That Connect to the CSC-PE Loopback, page 228
Configuring an eBGP Session Between the CSC-PE Router and the CSC-CE Loopback, page 229
Configuring an eBGP Session Between the CSC-CE Router and the CSC-PE Loopback, page 232
Verifying That Load Sharing Occurs Between Loopbacks, page 234
Configuring Loopback Interface Addresses on CSC-PE Routers
Perform this task to configure loopback interface addresses on the CSC-PE router.
Note
Configuration of a loopback interface address on the CSC-PE router requires the enabling of a VRF. The
CSC-CE router loopback interface does not require the enabling a of VRF.
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SUMMARY STEPS
1. enable
2. configure terminal
3. interface loopback interface number
4. ip vrf forwarding vrf-name
5. ip addres ip-address mask [secondary]
6. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 interface loopback interface number
Example:
Configures a software-only virtual interface that emulates an interface that
is always up, and enters interface configuration mode.
•
Router(config)# interface loopback 0
Step 4 ip vrf forwarding vrf-name
The interface-number argument is the number of the loopback
interface that you want to create or configure. There is no limit on the
number of loopback interfaces that you can create.
Associates a VRF with the specified interface or subinterface.
•
The vrf-name argument is the name assigned to a VRF.
Example:
Router(config-if)# ip vrf forwarding
vpn1
Step 5 ip addres ip-address mask [secondary]
Example:
Router(config-if)# ip address
10.20.20.20 255.255.255.255
Sets a primary or secondary IP address for an interface.
•
•
•
The ip-address argument is the IP address.
The mask argument is the mask for the associated IP subnet.
The secondary keyword specifies that the configured address is a
secondary IP address. If this keyword is omitted, the configured
address is the primary IP address.
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Command or Action
Purpose
Step 6 end
Exits to privileged EXEC mode.
Example:
Router(config)# end
Configuring Loopback Interface Addresses for CSC-CE Routers
Perform this task to configure loopback interface addresses for CSC-CE routers.
SUMMARY STEPS
1. enable
2. configure terminal
3. interface loopback interface-number
4. ip address ip-address mask [secondary]
5. end
DETAILED STEPS
Purpose
Command or Action
Step 1 enable
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 interface loopback interface-number
Configures a software-only virtual interface that emulates an interface that
is always up.
•
Example:
Router(config)# interface loopback 0
The interface-number argument is the number of the loopback
interface that you want to create or configure. There is no limit on the
number of loopback interfaces that you can create.
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Command or Action
Step 4 ip address ip-address mask [secondary]
Purpose
Sets a primary or secondary IP address for an interface.
•
•
•
Example:
Router(config-if)# ip address
10.10.10.10 255.255.255.255
Step 5 end
The ip-address argument is the IP address.
The mask argument is the mask for the associated IP subnet.
The secondary keyword specifies that the configured address is a
secondary IP address. If this keyword is omitted, the configured
address is the primary IP address.
Exits to privileged EXEC mode.
Example:
Router(config-if)# end
Configuring 32 Static Routes to the eBGP Neighbor Loopback on the CSC-PE Router
Perform the following task to configure /32 static routes to the eBGP neighbor loopback on the CSC-PE
router.
SUMMARY STEPS
1. enable
2. configure terminal
3. ip route vrf vrf-name prefix mask {ip-address | interface-type interface-number [ip-address]} [global]
[distance] [name] [permanent] [tag tag]
4. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
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Command or Action
Purpose
Step 3 ip route vrf vrf-name prefix mask {ipaddress | interface-type interface-number
[ip-address]} [global] [distance] [name]
[permanent] [tag tag]
Establishes static routes for a VRF.
•
•
•
•
Example:
•
Router(config)# ip route vrf vpn1
10.10.10.10 255.255.255.255 Ethernet
1/0 172.16.0.2
•
•
•
•
•
Step 4 end
The vrf-name argument is the name of the VRF for the static route.
The prefix argument is the IP route prefix for the destination.
The mask argument is the prefix mask for the destination.
The ip-address argument is the IP address of the next hop that you can
use to reach the destination network.
The interface-type and interface-number arguments are the network
interface type and interface number.
The global keyword specifies that the given next hop address is in the
nonVRF routing table.
The distance argument is an administrative distance.
The name argument applies a name to the specified route.
The permanent keyword specifies that the route is not to be removed,
even if the interface shuts down.
The tag tag keyword and argument name a tag value that can be used
as a “match” value for controlling redistribution via route maps.
Exits to privileged EXEC mode.
Example:
Router(config)# end
Configuring 32 Static Routes to the eBGP Neighbor Loopback on the CSC-CE Router
Perform the following task to configure /32 static routes to the eBGP neighbor loopback for the CSC-CE
router.
SUMMARY STEPS
1. enable
2. configure terminal
3. ip route prefix mask {ip-address | interface-type interface-number [ip-address]} [distance] [name]
[permanent] [tag tag]
4. end
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DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 ip route prefix mask {ip-address |
interface-type interface-number [ipaddress]} [distance] [name]
[permanent] [tag tag]
Establishes static routes.
•
•
•
Example:
•
Router(config)# ip route
10.20.20.20 255.255.255.255
Ethernet 1/0 172.16.0.1
•
•
•
•
Step 4 end
The prefix argument is the IP route prefix for the destination.
The mask argument is the prefix mask for the destination.
The ip-address argument is the IP address of the next hop that you can
use to reach the destination network.
The interface-type and interface-number arguments are the network
interface type and interface number.
The distance argument is an administrative distance.
The name argument applies a name to the specified route.
The permanent keyword specifies that the route is not to be removed,
even if the interface shuts down.
The tag tag keyword and argument name a tag value that can be used as a
“match” value for controlling redistribution via route maps.
Exits to privileged EXEC mode.
Example:
Router(config)# end
Configuring Forwarding on CSC-PE Interfaces That Connect to the CSC-CE Loopback
Perform this task to configure forwarding on CSC-PE interfaces that connect to the CSC-CE loopback.
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Configuring Forwarding on CSC-PE Interfaces That Connect to the CSC-CE Loopback
SUMMARY STEPS
1. enable
2. configure terminal
3. interface type slot/port
4. ip vrf forwarding vrf-name
5. ip address ip-address mask [secondary]
6. mpls bgp forwarding
7. exit
8. Repeat Steps 3 through 6 for another connecting interface (Ethernet 0/0).
9. end
DETAILED STEPS
Command or Action
Purpose
Step 1 enable
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 interface type slot/port
Configures an interface type and enters interface configuration mode.
•
•
Example:
Router(config)# interface ethernet 1/0
Step 4 ip vrf forwarding vrf-name
•
The type argument is the type of interface to be configured.
The slot argument is the slot number. Refer to the appropriate
hardware manual for slot and port information.
The /port argument is the port number. Refer to the appropriate
hardware manual for slot and port information.
Associates a VRF with an interface or subinterface.
•
The vrf-name argument is the name assigned to a VRF.
Example:
Router(config-if)# ip vrf forwarding vpn1
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Command or Action
Step 5 ip address ip-address mask [secondary]
Purpose
Sets a primary or secondary IP address for an interface.
•
•
•
Example:
Router(config-if)# ip address 172.16.0.1
255.255.255.255
Step 6 mpls bgp forwarding
The ip-address argument is the IP address.
The mask argument is the mask for the associated IP subnet.
The secondary keyword specifies that the configured address is a
secondary IP address. If this keyword is omitted, the configured
address is the primary IP address.
Configures BGP to enable MPLS forwarding on connecting interfaces.
Example:
Router(config-if)# mpls bgp forwarding
Step 7 exit
Exits to global configuration mode.
Example:
Router(config-if)# exit
Step 8 Repeat Steps 3 through 6 for another connecting
interface (Ethernet 0/0).
Step 9 end
Exits to privileged EXEC mode.
Example:
Router(config)# end
Configuring Forwarding on CSC-CE Interfaces That Connect to the CSC-PE Loopback
Perform this task to configure forwarding on CSC-CE interfaces that connect to the CSC-PE loopback.
SUMMARY STEPS
1. enable
2. configure terminal
3. interface typeslot/port
4. mpls bgp forwarding
5. exit
6. Repeat Steps 3 and 4 for another connecting interface (Ethernet 0/0).
7. end
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Configuring an eBGP Session Between the CSC-PE Router and the CSC-CE Loopback
DETAILED STEPS
Command or Action
Purpose
Step 1 enable
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 interface typeslot/port
Configures an interface type and enters interface configuration
mode.
•
•
Example:
Router(config)# interface ethernet 1/0
•
Step 4 mpls bgp forwarding
The type argument is the type of interface to be configured.
The slot argument is the slot number. Refer to the appropriate
hardware manual for slot and port information.
The /port argument is the port number. Refer to the
appropriate hardware manual for slot and port information.
Configures BGP to enable MPLS forwarding on connecting
interfaces.
Example:
Router(config-if)# mpls bgp forwarding
Step 5 exit
Exits to global configuration mode.
Example:
Router(config-if)# exit
Step 6 Repeat Steps 3 and 4 for another connecting interface
(Ethernet 0/0).
Step 7 end
Exits to privileged EXEC mode.
Example:
Router(config)# end
Configuring an eBGP Session Between the CSC-PE Router and the CSC-CE Loopback
Perform this task to configure an eBGP session between the CSC-PE router and the CSC-CE loopback.
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Configuring an eBGP Session Between the CSC-PE Router and the CSC-CE Loopback
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. bgp log-neighbor-changes
5. neighbor {ip-address | peer-group-name} remote-as as-number
6. neighbor {ip-address | peer-group-name} disable-connected-check
7. neighbor {ip-address | ipv6-address | peer-group-name} update-source interface-type interfacenumber
8. address-family ipv4 [unicast] vrf vrf-name
9. ip vrf forwarding vrf-name
10. neighbor {ip-address | peer-group-name | ipv6-address} activate
11. neighbor ip-address send-label
12. end
DETAILED STEPS
Command or Action
Step 1 enable
Purpose
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Configures the BGP routing process.
•
Example:
The as-number argument indicates the number of an autonomous
system that identifies the router to other BGP routers and tags the
routing information passed along.
Router(config)# router bgp 200
Step 4 bgp log-neighbor-changes
Enables logging of BGP neighbor resets.
Example:
Router(config-router)# bgp logneighbor-changes
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Command or Action
Purpose
Step 5 neighbor {ip-address | peer-group-name}
remote-as as-number
Example:
Adds an entry to the BGP or multiprotocol BGP neighbor table.
•
•
•
The ip-address argument is the IP address of the neighbor.
The peer-group-name argument is the name of a BGP peer group.
The as-number argument is the autonomous system to which the
neighbor belongs.
Router(config-router)# neighbor
10.10.10.10 remote-as 100
Step 6 neighbor {ip-address | peer-group-name}
disable-connected-check
Allows peering between loopbacks.
•
•
The ip-addressargument is the IP address of the neighbor.
The peer-group-name argument is the name of a BGP peer group.
Example:
Router(config-router)# neighbor
10.10.10.10 disable-connected-check
Step 7 neighbor {ip-address | ipv6-address | peer- Allows BGP sessions to use any operational interface for TCP connections.
group-name} update-source interface-type
• The ip-address argument is the IPv4 address of the BGP-speaking
interface-number
neighbor.
• The ipv6-address argument is the IPv6 address of the BGP-speaking
neighbor.
Example:
Router(config-router)# neighbor
10.10.10.10 update-source Loopback 0
This argument must be in the form documented in RFC 2373, where the
address is specified in hexadecimal using 16-bit values between colons.
•
•
•
Step 8 address-family ipv4 [unicast] vrf vrfname
Enters address family configuration mode for configuring routing protocols
such as BGP, Routing Information Protocol (RIP), and static routing.
•
Example:
Router(config-router)# addressfamily ipv4 vrf vpn1
Step 9 ip vrf forwarding vrf-name
The peer-group-name argument is the name of a BGP peer group.
The interface-type argument is the interface type.
The interface-number argument is the interface number.
•
•
The ipv4 keyword configures sessions that carry standard IPv4 address
prefixes.
The unicast keyword specifies unicast prefixes.
The vrf vrf-name keyword and argument specify the name of a VRF to
associate with submode commands.
Associates a VRF with an interface or subinterface.
•
The vrf-name argument is the name assigned to a VRF.
Example:
Router(config-router-af)# ip vrf
forwarding vpn1
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Command or Action
Step 10 neighbor {ip-address | peer-group-name |
ipv6-address} activate
Example:
Router(config-router-af)# neighbor
10.10.10.10 activate
Purpose
Enables the exchange of information with a BGP neighbor.
•
•
•
The ip-address argument is the IP address of the neighboring router.
The peer-group-name argument is the name of the BGP peer group.
The ipv6-address argument is the IPv6 address of the BGP-speaking
neighbor.
Note This argument must be in the form documented in RFC 2373, where
the address is specified in hexadecimal using 16-bit values between
colons.
Step 11 neighbor ip-address send-label
Enables a BGP router to send MPLS labels with BGP routes to a
neighboring BGP router.
•
Example:
The ip-addressargument is the IP address of the neighboring router.
Router(config-router-af)# neighbor
10.10.10.10 send-label
Step 12 end
Exits to privileged EXEC mode.
Example:
Router(config)# end
Configuring an eBGP Session Between the CSC-CE Router and the CSC-PE Loopback
Perform this task to configure an eBGP session between the CSC-CE router and the CSC-PE loopback.
SUMMARY STEPS
1. enable
2. configure terminal
3. router bgp as-number
4. bgp log-neighbor-changes
5. neighbor {ip-address | peer-group-name} remote-as as-number
6. neighbor {ip-address | peer-group-name} disable-connected-check
7. neighbor {ip-address | ipv6-address | peer-group-name} update-source interface-type interfacenumber
8. address-family ipv4 [unicast] [vrf vrf-name]
9. neighbor {ip-address | peer-group-name|ipv6-address] activate
10. neighbor ip-address send-label
11. end
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Configuring an eBGP Session Between the CSC-CE Router and the CSC-PE Loopback
DETAILED STEPS
Command or Action
Purpose
Step 1 enable
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 configure terminal
Enters global configuration mode.
Example:
Router# configure terminal
Step 3 router bgp as-number
Configures the BGP routing process.
•
Example:
The as-number argument indicates the number of an autonomous
system that identifies the router to other BGP routers and tags the
routing information passed along.
Router(config)# router bgp 200
Step 4 bgp log-neighbor-changes
Enables logging of BGP neighbor resets.
Example:
Router(config-router)# bgp logneighbor-changes
Step 5 neighbor {ip-address | peer-group-name}
remote-as as-number
Example:
Adds an entry to the BGP or multiprotocol BGP neighbor table.
•
•
•
The ip-address argument is the IP address of the neighbor.
The peer-group-name argument is the name of a BGP peer group.
The as-number argument is the autonomous system to which the
neighbor belongs.
Router(config-router)# neighbor
10.20.20.20 remote-as 100
Step 6 neighbor {ip-address | peer-group-name}
disable-connected-check
Allows peering between loopbacks.
•
•
The ip-address argument is the IP address of the neighbor.
The peer-group-name argument is the name of a BGP peer group.
Example:
Router(config-router)# neighbor
10.20.20.20 disable-connected-check
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Command or Action
Purpose
Step 7 neighbor {ip-address | ipv6-address | peer- Allows BGP sessions to use any operational interface for TCP connections.
group-name} update-source interface-type
• The ip-address argument is the IPv4 address of the BGP-speaking
interface-number
neighbor.
• The ipv6-address argument is the IPv6 address of the BGP-speaking
neighbor.
Example:
Router(config-router)# neighbor
10.20.20.20 update-source Loopback 0
This argument must be in the form documented in RFC 2373, where the
address is specified in hexadecimal using 16-bit values between colons.
•
•
•
Step 8 address-family ipv4 [unicast] [vrf vrfname]
Enters address family configuration mode for configuring routing protocols
such as BGP, RIP, and static routing.
•
Example:
Router(config-router)# addressfamily ipv4
Step 9 neighbor {ip-address | peer-group-name|
ipv6-address] activate
Example:
Router(config-router-af)# neighbor
10.20.20.20 activate
The peer-group-name argument is the name of a BGP peer group.
The interface-type argument is the interface type.
The interface-number argument is the interface number.
•
•
The ipv4 keyword configures sessions that carry standard IPv4 address
prefixes.
The unicast keyword specifies unicast prefixes.
The vrf vrf-name keyword and argument specify the name of a VRF to
associate with submode commands.
Enables the exchange of information with a BGP neighbor.
•
•
•
The ip-address argument is the IP address of the neighboring router.
The peer-group-name argument is the name of the BGP peer group.
The ipv6-address argument is the IPv6 address of the BGP-speaking
neighbor.
Note This argument must be in the form documented in RFC 2373, where
the address is specified in hexadecimal using 16-bit values between
colons.
Step 10 neighbor ip-address send-label
Example:
Enables a BGP router to send MPLS labels with BGP routes to a
neighboring BGP router.
•
The ip-address argument is the IP address of the neighboring router.
Router(config-router-af)# neighbor
10.20.20.20 send-label
Step 11 end
Exits to privileged EXEC mode.
Example:
Router(config)# end
Verifying That Load Sharing Occurs Between Loopbacks
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Configuration Examples for Load Sharing MPLS VPN Traffic
To verify that load sharing occurs between loopbacks, ensure that the MPLS LFIB entry for the neighbor
route lists the available paths and interfaces.
SUMMARY STEPS
1. enable
2. show mpls forwarding-table [vrf vrf-name] [{network {mask | length} | labels label [-label] |
[ interface] interface | next-hop address | lsp-tunnel [tunnel-id]}] [detail]
3. disable
DETAILED STEPS
Command or Action
Purpose
Step 1 enable
Enables privileged EXEC mode.
•
Enter your password if prompted.
Example:
Router> enable
Step 2 show mpls forwarding-table [vrf vrf-name] [{network {mask | length} |
labels label [-label] | [ interface] interface | next-hop address | lsp-tunnel
[tunnel-id]}] [detail]
Displays the contents of the MPLS LFIB.
Example:
Router# show mpls forwarding-table
Step 3 disable
Exits to user EXEC mode.
Example:
Router# disable
Configuration Examples for Load Sharing MPLS VPN Traffic
• Configuring a Router to Select eBGP or iBGP Paths as Multipaths Example, page 236
• Configuring a 32 Static Route from an ASBR to the Loopback Address of Another ASBR Examples,
page 236
• Configuring BGP MPLS Forwarding on the Interfaces Connecting ASBRs Example, page 236
• Configuring VPNv4 Sessions on an ASBR Example, page 236
• Verifying VPN NLRI for a Specified Network Example, page 237
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Configuration Examples for Load Sharing MPLS VPN Traffic
Configuring a Router to Select eBGP or iBGP Paths as Multipaths Example
The following example configures a router in address family configuration mode to select six eBGP or
iBGP paths as multipaths:
Router(config)# router bgp 100
Router(config-router)# address-family ipv4 vrf try
Router(config-router-af)# maximum-paths eibgp 6
Router(config-router-af)# end
Configuring a 32 Static Route from an ASBR to the Loopback Address of
Another ASBR Examples
The following example configures a /32 static route from ASBR1 to the loopback address of ASBR2:
Router# configure terminal
Router(config)# ip route 10.20.20.20 255.255.255 e1/0 168.192.0.1
Router(config)# ip route 10.20.20.20 255.255.255 e0/0 168.192.2.1
The following example configures a /32 static route from ASBR2 to the loopback address of ASBR1:
Router# configure terminal
Router(config)# ip route vrf vpn1 10.10.10.10 255.255.255 e1/0 168.192.0.2
Router(config)# ip route vrf vpn1 10.10.10.10 255.255.255 e0/0 168.192.2.2
Configuring BGP MPLS Forwarding on the Interfaces Connecting ASBRs
Example
The following example configures BGP/MPLS forwarding on the interfaces connecting ASBR2 with
ASBR1:
Router# configure terminal
Router(config)# interface ethernet 1/0
Router(config-if)# ip vrf forwarding vpn1
Router(config-if)# ip address 168.192.0.1 255.255.255.255
Router(config-if)# mpls bgp forwarding
Router(config-if)# exit
Router(config)# interface ethernet 0/0
Router(config-if)# ip vrf forwarding vpn1
Router(config-if)# ip address 168.192.2.1 255.255.255.255
Router(config-if)# mpls bgp forwarding
Router(config-if)# exit
Configuring VPNv4 Sessions on an ASBR Example
The following example configures VPNv4 sessions on ASBR2:
Router# configure terminal
Router(config)# router bgp 200
Router(config-router)# bgp log-neighbor-changes
Router(config-router)# neighbor 10.10.10.10 remote-as 100
Router(config-router)# neighbor 10.10.10.10 disable-connected-check
Router(config-router)# neighbor 10.10.10.10 update-source Loopback0
!
Router(config-router)# address-family vpnv4
Router(config-router-af)# neighbor 10.10.10.10 activate
Router(config-router-af)# neighbor 10.10.10.10 send-community extended
Router(config-router-af)# end
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Additional References
Verifying VPN NLRI for a Specified Network Example
If you enter the all keyword with the show ip bgp vpnv4 command, the output displays information about
all VPN network layer reachability information (NLRI) for a specified network:
Router# show ip bgp vpnv4 all 10.22.22.0
BGP routing table entry for 10:1:22.22.22.0/24, version 19
Paths:(5 available, best #5)
Multipath: eiBGP
Advertised to non peer-group peers:
10.0.0.2 10.0.0.3 10.0.0.4 10.0.0.5
22
10.0.0.2 (metric 20) from 10.0.0.4 (10.0.0.4)
Origin IGP, metric 0, localpref 100, valid, internal,
Extended Community:0x0:0:0 RT:100:1 0x0:0:0
Originator:10.0.0.2, Cluster list:10.0.0.4
22
10.0.0.2 (metric 20) from 10.0.0.5 (10.0.0.5)
Origin IGP, metric 0, localpref 100, valid, internal,
Extended Community:0x0:0:0 RT:100:1 0x0:0:0
Originator:10.0.0.2, Cluster list:10.0.0.5
22
10.0.0.2 (metric 20) from 10.0.0.2 (10.0.0.2)
Origin IGP, metric 0, localpref 100, valid, internal,
Extended Community:RT:100:1 0x0:0:0
22
10.0.0.2 (metric 20) from 10.0.0.3 (10.0.0.3)
Origin IGP, metric 0, localpref 100, valid, internal,
Extended Community:0x0:0:0 RT:100:1 0x0:0:0
Originator:10.0.0.2, Cluster list:10.0.0.3
22
10.1.1.12 from 10.1.1.12 (10.22.22.12)
Origin IGP, metric 0, localpref 100, valid, external,
Extended Community:RT:100:1
multipath
multipath
multipath
multipath
multipath, best
Additional References
Related Documents
Related Topic
Document Title
MPLS
MPLS: Layer 3 VPNs: Inter-AS and CSC
Configuration Guide, MPLS VPN Carrier
Supporting Carrier with BGP
BGP
Cisco IOS IP Routing: BGP Configuration Guide,
Configuring BGP
Standards
Standard
Title
No new or modified standards are supported by this -feature, and support for existing standards has not
been modified by this feature.
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Additional References
MIBs
MIB
MIBs Link
No new or modified MIBs are supported by this
feature, and support for existing MIBs has not been
modified by this feature.
To locate and download MIBs for selected
platforms, Cisco software releases, and feature sets,
use Cisco MIB Locator found at the following
URL:
http://www.cisco.com/go/mibs
RFCs
RFC
Title
RFC 1164
Application of the Border Gateway Protocol in the
Internet
RFC 1171
A Border Gateway Protocol 4
RFC 1700
Assigned Numbers
RFC 1966
BGP Route Reflection: An Alternative to Full Mesh
IBGP
RFC 2283
Multiprotocol Extensions for BGP-4
RFC 2373
IP Version 6 Addressing Architecture
RFC 2547
BGP/MPLS VPNs
RFC 2842
Capabilities Advertisement with BGP-4
RFC 2858
Multiprotocol Extensions for BGP-4
RFC 3107
Carrying Label Information in BGP-4
Technical Assistance
Description
Link
The Cisco Support website provides extensive
http://www.cisco.com/techsupport
online resources, including documentation and tools
for troubleshooting and resolving technical issues
with Cisco products and technologies.
To receive security and technical information about
your products, you can subscribe to various
services, such as the Product Alert Tool (accessed
from Field Notices), the Cisco Technical Services
Newsletter, and Really Simple Syndication (RSS)
Feeds.
Access to most tools on the Cisco Support website
requires a Cisco.com user ID and password.
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Feature Information for Load Sharing MPLS VPN Traffic
Feature Information for Load Sharing MPLS VPN Traffic
The following table provides release information about the feature or features described in this module.
This table lists only the software release that introduced support for a given feature in a given software
release train. Unless noted otherwise, subsequent releases of that software release train also support that
feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support.
To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Table 11
Feature Information for Load Sharing MPLS VPN Traffic
Feature Name
Releases
Feature Configuration Information
MPLS VPN--Load Balancing
Support for Inter-AS and CSC
VPNs
12.0(29)S
This feature allows MPLS VPN
Inter-AS and MPLS VPN CSC
networks to load share traffic
between adjacent LSRs that are
connected by multiple links. The
LSRs can be a pair of ASBRs or a
CSC-PE and a CSC-CE. Using
directly connected loopback
peering allows load sharing at the
IGP level, so more than one BGP
session is not needed between the
LSRs. No other label distribution
mechanism is needed between the
adjacent LSRs than BGP.
BGP Multipath Load Sharing for
Both eBGP and iBGP in an
MPLS VPN
12.2(4)T
12.4(20)T
12.2(14)S
12.0(24)S
iBGP Multipath Load Sharing
12.2(2)T
12.2(14)S
eBGP Multipath
12.0(27)S
This feature allows multihomed
autonomous systems and PE
routers to be configured to
distribute traffic across both
external BGP (eBGP) and
internal BGP (iBGP) paths.
This feature enables the BGP
speaking router to select multiple
iBGP paths as the best paths to a
destination.
This feature installs multiple
paths in the IP routing table when
the eBGP paths are learned from
a neighboring Autonomous
System (AS), instead of picking
one best path.
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Load Sharing MPLS VPN Traffic
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Third-party trademarks mentioned are the property of their respective owners. The use of the word partner
does not imply a partnership relationship between Cisco and any other company. (1110R)
Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be
actual addresses and phone numbers. Any examples, command display output, network topology diagrams,
and other figures included in the document are shown for illustrative purposes only. Any use of actual IP
addresses or phone numbers in illustrative content is unintentional and coincidental.
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