MPLS WAN Technology Design Guide - December 2013

MPLS WAN Technology Design Guide - December 2013
MPLS WAN
Technology Design Guide
December 2013
Table of Contents
Preface.........................................................................................................................................1
CVD Navigator..............................................................................................................................2
Use Cases................................................................................................................................... 2
Scope.......................................................................................................................................... 2
Proficiency................................................................................................................................... 2
Introduction..................................................................................................................................3
Related Reading........................................................................................................................... 3
Technology Use Cases................................................................................................................ 3
Use Case: Site-to-Site Communications Using MPLS L3VPN Services.................................. 3
Design Overview.......................................................................................................................... 4
WAN Design............................................................................................................................ 4
MPLS WAN Transport.............................................................................................................. 4
Ethernet WAN.......................................................................................................................... 4
WAN-Aggregation Designs...................................................................................................... 5
MPLS Static Design Model...................................................................................................... 6
MPLS Dynamic Design Model................................................................................................. 6
Dual MPLS Design Model........................................................................................................ 7
WAN Remote-Site Designs..................................................................................................... 7
WAN/LAN Interconnection....................................................................................................... 8
WAN Remote Sites—LAN Topology......................................................................................... 9
Layer 2 Access....................................................................................................................... 9
Distribution and Access Layer................................................................................................11
IP Multicast.............................................................................................................................13
Quality of Service.......................................................................................................................13
Deploying the WAN....................................................................................................................15
Overall WAN Architecture Design Goals..................................................................................... 15
IP Routing.............................................................................................................................. 15
LAN Access.......................................................................................................................... 15
High Availability...................................................................................................................... 15
Path Selection Preferences................................................................................................... 15
Quality of Service (QoS)........................................................................................................ 16
Design Parameters................................................................................................................ 16
Table of Contents
Deploying an MPLS WAN............................................................................................................ 17
Design Overview.........................................................................................................................17
WAN-Aggregation—MPLS CE Routers....................................................................................17
Remote Sites—MPLS CE Router Selection............................................................................. 18
Design Details........................................................................................................................19
Deployment Details ................................................................................................................... 22
Configuring the MPLS CE Router.......................................................................................... 22
Configuring the Remote-Site MPLS CE Router...................................................................... 33
Adding a Secondary MPLS Link on an Existing MPLS CE Router.......................................... 54
Configuring the Secondary Remote-Site Router.................................................................... 59
Deploying a WAN Remote-Site Distribution Layer.......................................................................75
Deployment Details.................................................................................................................... 75
Connecting the Single or Primary Remote-Site Router to the Distribution Layer.................... 75
Connecting the Secondary Remote-Site Router to the Distribution Layer............................. 81
Deploying WAN Quality of Service..............................................................................................86
Deployment Details.................................................................................................................... 86
Configuring QoS.................................................................................................................... 86
Appendix A: Product List............................................................................................................91
Appendix B: Device Configuration Files.......................................................................................94
Appendix C: Changes.................................................................................................................95
Table of Contents
Preface
Cisco Validated Designs (CVDs) provide the foundation for systems design based on common use cases or
current engineering system priorities. They incorporate a broad set of technologies, features, and applications to
address customer needs. Cisco engineers have comprehensively tested and documented each CVD in order to
ensure faster, more reliable, and fully predictable deployment.
CVDs include two guide types that provide tested and validated design and deployment details:
• Technology design guides provide deployment details, information about validated products and
software, and best practices for specific types of technology.
• Solution design guides integrate or reference existing CVDs, but also include product features and
functionality across Cisco products and may include information about third-party integration.
Both CVD types provide a tested starting point for Cisco partners or customers to begin designing and deploying
systems using their own setup and configuration.
How to Read Commands
Many CVD guides tell you how to use a command-line interface (CLI) to configure network devices. This section
describes the conventions used to specify commands that you must enter.
Commands to enter at a CLI appear as follows:
configure terminal
Commands that specify a value for a variable appear as follows:
ntp server 10.10.48.17
Commands with variables that you must define appear as follows:
class-map [highest class name]
Commands at a CLI or script prompt appear as follows:
Router# enable
Long commands that line wrap are underlined. Enter them as one command:
police rate 10000 pps burst 10000 packets conform-action set-discard-classtransmit 48 exceed-action transmit
Noteworthy parts of system output or device configuration files appear highlighted, as follows:
interface Vlan64
ip address 10.5.204.5 255.255.255.0
Comments and Questions
If you would like to comment on a guide or ask questions, please use the feedback form.
For the most recent CVD guides, see the following site:
http://www.cisco.com/go/cvd/wan
Preface
December 2013
1
CVD Navigator
The CVD Navigator helps you determine the applicability of this guide by summarizing its key elements: the use cases, the
scope or breadth of the technology covered, the proficiency or experience recommended, and CVDs related to this guide.
This section is a quick reference only. For more details, see the Introduction.
Use Cases
This guide addresses the following technology use cases:
• Site-to-Site Communications Using MPLS L3VPN Services—
Many organizations are deploying Multiprotocol Label
Switching (MPLS) WAN services in order to connect remote
locations over private cloud Layer 3 VPN-based providermanaged MPLS networks.
Related CVD Guides
VALIDATED
DESIGN
For more information, see the “Use Cases” section in this guide.
Scope
VALIDATED
DESIGN
Campus Wired LAN
Technology Design Guide
GET VPN Technology
Design Guide
This guide covers the following areas of technology and products:
• WAN design using Layer 3 MPLS services for central and
remote sites
VALIDATED
DESIGN
VPN WAN Technology
Design Guide
• Remote-site WAN redundancy options
• Routing policy and control for WAN aggregation and remote
sites
• WAN quality of service (QoS) design and configuration
For more information, see the “Design Overview” section in this
guide.
Proficiency
This guide is for people with the following technical proficiencies—or
equivalent experience:
• CCNP Routing and Switching—3 to 5 years planning,
implementing, verifying, and troubleshooting local and widearea networks
To view the related CVD guides,
click the titles or visit the following site:
http://www.cisco.com/go/cvd/wan
CVD Navigator
December 2013
2
Introduction
The MPLS WAN Technology Design Guide, provides flexible guidance and configuration for Multiprotocol Label
Switching (MPLS) transport.
Related Reading
The Layer 2 WAN Technology Design Guide provides guidance and configuration for a VPLS or Metro Ethernet
transport.
The VPN WAN Technology Design Guide provides guidance and configuration for broadband or Internet transport
in a both a primary or backup role.
Technology Use Cases
For remote-site users to effectively support the business, organizations require that the WAN provide sufficient
performance and reliability. Although most of the applications and services that the remote-site worker uses
are centrally located, the WAN design must provide a common resource access experience to the workforce,
regardless of location.
To control operational costs, the WAN must support the convergence of voice, video, and data transport onto
a single, centrally managed infrastructure. As organizations move into multinational or global business markets,
they require a flexible network design that allows for country-specific access requirements and controls
complexity. The ubiquity of carrier-provided MPLS networks makes it a required consideration for an organization
building a WAN.
To reduce the time needed to deploy new technologies that support emerging business applications and
communications, the WAN architecture requires a flexible design. The ability to easily scale bandwidth or to add
additional sites or resilient links makes MPLS an effective WAN transport for growing organizations.
Use Case: Site-to-Site Communications Using MPLS L3VPN Services
This guide helps organizations deploy WAN services in order to connect remote locations over private cloud
Layer 3 VPN-based provider managed MPLS services.
This design guide enables the following network capabilities:
• IP any-to-any WAN connectivity for up to 500 remote sites and one or two central hub site locations
• Deployment of single or dual MPLS service providers for resiliency using single or dual routers in remote
site locations
• Static routing or dynamic BGP peering with the MPLS service provider for site-to-site communications.
• Support for Layer 2 or Layer 3 distribution switching designs
• Support for IP multicast using Multicast VPN (mVPN) service provider-based offering
• QoS for WAN traffic such as Voice over IP (VoIP) and business critical applications
Introduction
December 2013
3
Design Overview
This guide, the MPLS WAN Technology Design Guide, provides a design that enables highly available, secure,
and optimized connectivity for multiple remote-site LANs.
The WAN is the networking infrastructure that provides an IP-based interconnection between remote sites that
are separated by large geographic distances.
This document shows you how to deploy the network foundation and services to enable the following:
• MPLS WAN connectivity for up to 500 remote sites
• Primary and secondary links to provide redundant topology options for resiliency
• Wired LAN access at all remote sites
WAN Design
The primary focus of the design is to allow usage of the following commonly deployed WAN transports:
• Multiprotocol Label Switching (MPLS) Layer 3 VPN (primary)
• Multiprotocol Label Switching (MPLS) Layer 3 VPN (secondary)
• Internet VPN (secondary)
At a high level, the WAN is an IP network, and these transports can be easily integrated to the design. The
chosen architecture designates a primary WAN-aggregation site that is analogous to the hub site in a traditional
hub-and-spoke design. This site has direct connections to both WAN transports and high-speed connections
to the selected service providers. In addition, the site uses network equipment scaled for high performance
and redundancy. The primary WAN-aggregation site is coresident with the data center and usually the primary
campus or LAN as well.
The usage of an Internet VPN transport to provide a redundant topology option for resiliency is covered in the
VPN WAN Technology Design Guide.
MPLS WAN Transport
Cisco IOS Software Multiprotocol Label Switching (MPLS) enables enterprises and service providers to build
next-generation, intelligent networks that deliver a wide variety of advanced, value-added services over a single
infrastructure. You can integrate this economical solution seamlessly over any existing infrastructure, such as IP,
Frame Relay, ATM, or Ethernet.
MPLS Layer 3 VPNs use a peer-to-peer VPN Model that leverages the Border Gateway Protocol (BGP) to
distribute VPN-related information. This peer-to-peer model allows enterprise subscribers to outsource routing
information to service providers, which can result in significant cost savings and a reduction in operational
complexity for enterprises.
Subscribers who need to transport IP multicast traffic can enable Multicast VPNs (MVPNs).
The WAN leverages MPLS VPN as a primary WAN transport or as a backup WAN transport (to an alternate MPLS
VPN primary).
Ethernet WAN
Both of the WAN transports mentioned previously use Ethernet as a standard media type. Ethernet is becoming a
dominant carrier handoff in many markets and it is relevant to include Ethernet as the primary media in the tested
architectures. Much of the discussion in this guide can also be applied to non-Ethernet media (such as T1/E1,
DS-3, OC-3, and so on), but they are not explicitly discussed.
Introduction
December 2013
4
WAN-Aggregation Designs
The WAN-aggregation (hub) designs include two or more WAN edge routers. When WAN edge routers are
referred to in the context of the connection to a carrier or service provider, they are typically known as customer
edge (CE) routers. All of the WAN edge routers connect into a distribution layer.
The WAN transport options include MPLS VPN used as a primary or secondary transport. Each transport
connects to a dedicated CE router. A similar method of connection and configuration is used for both.
This design guide documents multiple WAN-aggregation design models that are statically or dynamically routed
with either single or dual MPLS carriers. The primary differences between the various designs are the usage of
routing protocols and the overall scale of the architecture. For each design model, you can select several router
platforms with differing levels of performance and resiliency capabilities.
Each of the design models is shown with LAN connections into either a collapsed core/distribution layer or a
dedicated WAN distribution layer. There are no functional differences between these two methods from the
WAN-aggregation perspective.
In all of the WAN-aggregation designs, tasks such as IP route summarization are performed at the distribution
layer. There are other various devices supporting WAN edge services, and these devices should also connect
into the distribution layer.
Each MPLS carrier terminates to a dedicated WAN router with a primary goal of eliminating any single points of
failure. A single VPN hub router is used across both designs. The various design models are contrasted in the
following table.
Table 1 - WAN-aggregation design models
MPLS Static
MPLS Dynamic
Dual MPLS
Remote sites
Up to 50
Up to 100
Up to 500
WAN links
Single
Single
Dual
Edge routers
Single
Single
Dual
WAN routing protocol
None (static)
BGP (dynamic)
BGP (dynamic)
Transport 1
MPLS VPN A
MPLS VPN A
MPLS VPN A
Transport 2
—
—
MPLS VPN B
The characteristics of each design are discussed in the following sections.
Introduction
December 2013
5
MPLS Static Design Model
• Supports up to 50 remote sites
• Has a single MPLS VPN carrier
• Uses static routing with MPLS VPN carrier
The MPLS Static design model is shown in the following figure.
Figure 1 - MPLS Static and MPLS Dynamic design models (single MPLS carrier)
Core Layer
Distribution
Layer
Collapsed Core/
Distribution Layer
MPLS CE Router
MPLS CE Router
MPLS
MPLS
2183
Static Routing or
BGP Dynamic Routing
MPLS Dynamic Design Model
• Supports up to 100 remote sites
• Has a single MPLS VPN carrier
• Uses BGP routing with MPLS VPN carrier
The MPLS Dynamic design model is shown in Figure 1.
Introduction
December 2013
6
Dual MPLS Design Model
• Supports up to 500 remote sites
• Has multiple MPLS VPN carriers
• Uses BGP routing with MPLS VPN carrier
• Typically used with a dedicated WAN distribution layer
The Dual MPLS design model is shown in the following figure.
Figure 2 - Dual MPLS design model
Core Layer
Collapsed Core/
Distribution Layer
MPLS CE
Routers
Distribution
Layer
MPLS CE
Routers
MPLS A
BGP
Dynamic
Routing
MPLS B
MPLS A
MPLS B
2184
BGP
Dynamic
Routing
WAN Remote-Site Designs
This guide documents multiple WAN remote-site designs, and they are based on various combinations of WAN
transports mapped to the site specific requirements for service levels and redundancy.
Figure 3 - WAN remote-site designs
MPLS WAN
Nonredundant
MPLS-A
MPLS-B
Redundant Links
& Routers
MPLS-A
MPLS-B
2117
MPLS
Redundant Links
Introduction
December 2013
7
The remote-site designs include single or dual WAN edge routers. These are always MPLS CE routers.
Most remote sites are designed with a single router WAN edge; however, certain remote-site types require a
dual router WAN edge. Dual router candidate sites include regional office or remote campus locations with large
user populations, or sites with business critical needs that justify additional redundancy to remove single points
of failure.
The overall WAN design methodology is based on a primary WAN-aggregation site design that can
accommodate all of the remote-site types that map to the various link combinations listed in the following table.
Table 2 - WAN remote-site transport options
WAN remote-site routers
WAN transports
Primary transport
Secondary transport
Single
Single
MPLS VPN A
—
Single
Dual
MPLS VPN A
MPLS VPN B
Dual
Dual
MPLS VPN A
MPLS VPN B
The modular nature of the network design enables you to create design elements that you can replicate
throughout the network.
Both WAN-aggregation designs and all of the WAN remote-site designs are standard building blocks in the
overall design. Replication of the individual building blocks provides an easy way to scale the network and allows
for a consistent deployment method.
WAN/LAN Interconnection
The primary role of the WAN is to interconnect primary site and remote-site LANs. The LAN discussion within
this guide is limited to how the WAN-aggregation site LAN connects to the WAN-aggregation devices and how
the remote-site LANs connect to the remote-site WAN devices. Specific details regarding the LAN components
of the design are covered in the Campus Wired LAN Technology Design Guide.
At remote sites, the LAN topology depends on the number of connected users and physical geography of the
site. Large sites may require the use of a distribution layer to support multiple access-layer switches. Other sites
may only require an access-layer switch directly connected to the WAN remote-site routers. The variants that
are tested and documented in this guide are shown in the following table.
Table 3 - WAN remote-site LAN options
WAN remote-site routers
WAN transports
LAN topology
Single
Single
Access only
Distribution/access
Single
Dual
Access only
Distribution/access
Dual
Dual
Access only
Distribution/access
Introduction
December 2013
8
WAN Remote Sites—LAN Topology
For consistency and modularity, all WAN remote sites use the same VLAN assignment scheme, which is shown
in the following table. This design guide uses a convention that is relevant to any location that has a single access
switch and this model can also be easily scaled to additional access closets through the addition of a distribution
layer.
Table 4 - WAN remote-sites—VLAN assignment
VLAN
Usage
Layer 2 access
Layer 3 distribution/ access
VLAN 64
Data
Yes
—
VLAN 69
Voice
Yes
—
VLAN 99
Transit
Yes
Yes
(dual router only)
(dual router only)
VLAN 50
Router link (1)
—
Yes
VLAN 54
Router link (2)
—
Yes
(dual router only)
Layer 2 Access
WAN remote sites that do not require additional distribution layer routing devices are considered to be flat or
from a LAN perspective they are considered unrouted Layer 2 sites. All Layer 3 services are provided by the
attached WAN routers. The access switches, through the use of multiple VLANs, can support services such as
data and voice. The design shown in the following figure illustrates the standardized VLAN assignment scheme.
The benefits of this design are clear: all of the access switches can be configured identically, regardless of the
number of sites in this configuration.
Access switches and their configuration are not included in this guide. The Campus Wired LAN Technology
Design Guide provides configuration details on the various access switching platforms.
IP subnets are assigned on a per-VLAN basis. This design only allocates subnets with a 255.255.255.0 netmask
for the access layer, even if less than 254 IP addresses are required. (This model can be adjusted as necessary
to other IP address schemes.) The connection between the router and the access switch must be configured
for 802.1Q VLAN trunking with subinterfaces on the router that map to the respective VLANs on the switch. The
various router subinterfaces act as the IP default gateways for each of the IP subnet and VLAN combinations.
Figure 4 - WAN remote site—Flat Layer 2 LAN (single router)
MPLS
VLAN 64 - Data
VLAN 69 - Voice
802.1Q VLAN Trunk (64, 69)
Introduction
2118
No HSRP
Required
December 2013
9
A similar LAN design can be extended to a dual-router edge as shown in the following figure. This design change
introduces some additional complexity. The first requirement is to run a routing protocol. You need to configure
Enhanced Interior Gateway Protocol (EIGRP) between the routers. For consistency with the primary site LAN, use
EIGRP process 100.
Because there are now two routers per subnet, a First Hop Redundancy Protocol (FHRP) must be implemented.
For this design, Cisco selected Hot Standby Router Protocol (HSRP) as the FHRP. HSRP is designed to allow for
transparent failover of the first-hop IP router. HSRP ensures high network availability by providing first-hop routing
redundancy for IP hosts configured with a default gateway IP address. HSRP is used in a group of routers for
selecting an active router and a standby router. When there are multiple routers on a LAN, the active router is the
router of choice for routing packets; the standby router is the router that takes over when the active router fails or
when preset conditions are met.
Figure 5 - WAN remote site—Flat Layer 2 LAN (dual router)
MPLS
MPLS
iBGP
EIGRP
VLAN99 - Transit
HSRP VLANs
Active HSRP Router
VLAN 64 - Data
802.1Q VLAN Trunk (64, 69, 99)
2119
VLAN 69 - Voice
Enhanced Object Tracking (EOT) provides a consistent methodology for various router and switching features to
conditionally modify their operation based on information objects available within other processes. The objects
that can be tracked include interface line protocol, IP route reachability, and IP service-level agreement (SLA)
reachability, as well as several others.
The IP SLA feature provides a capability for a router to generate synthetic network traffic that can be sent to a
remote responder. The responder can be a generic IP endpoint that can respond to an Internet Control Message
Protocol (ICMP) echo (ping) request, or can be a Cisco router running an IP SLA responder process, that can
respond to more complex traffic such as jitter probes. The use of IP SLA allows the router to determine endto-end reachability to a destination and also the roundtrip delay. More complex probe types can also permit the
calculation of loss and jitter along the path. IP SLA is used in tandem with EOT within this design.
In order to improve convergence times after an MPLS WAN failure, HSRP has the capability to monitor the
reachability of a next-hop IP neighbor through the use of EOT and IP SLA. This combination allows for a router
to give up its HSRP Active role if its upstream neighbor becomes unresponsive. This provides additional network
resiliency.
Introduction
December 2013
10
Figure 6 - WAN remote-site—IP SLA probe to verify upstream device reachability
Detailed View
IP SLA Probe
as Tracked Object
WAN
IP SLA
Probe
WAN
Interface
Upstream
Interface
WAN
WAN
R1
EIGRP
VLAN 99 - Transit
HSRP VLANs
VLAN 64 - Data
VLAN 69 - Voice
2142
802.1Q VLAN Trunk
(64, 69, 99)
Active
HSRP Router
HSRP is configured to be active on the router with the highest priority WAN transport. EOT of IP SLA probes is
implemented in conjunction with HSRP so that in the case of WAN transport failure, the standby HSRP router
associated with the lower priority (alternate) WAN transport becomes the active HSRP router. The IP SLA probes
are sent from the MPLS CE router to the MPLS Provider Edge (PE) router in order to ensure reachability of the
next hop router. This is more effective than simply monitoring the status of the WAN interface.
The dual router designs also warrant an additional component that is required for proper routing in certain
scenarios. In these cases, a traffic flow from a remote-site host might be sent to a destination reachable via the
alternate WAN transport (for example, an MPLS A + MPLS B remote site communicating with an MPLS-B-only
remote site). The primary WAN transport router then forwards the traffic out the same data interface to send it to
the alternate WAN transport router, which then forwards the traffic to the proper destination. This is referred to as
hairpinning.
The appropriate method to avoid sending the traffic out the same interface is to introduce an additional link
between the routers and designate the link as a transit network (VLAN 99). There are no hosts connected to
the transit network, and it is only used for router-router communication. The routing protocol runs between
router subinterfaces assigned to the transit network. No additional router interfaces are required with this design
modification because the 802.1Q VLAN trunk configuration can easily accommodate an additional subinterface.
Distribution and Access Layer
Large remote sites may require a LAN environment similar to that of a small campus LAN that includes a
distribution layer and access layer. This topology works well with either a single or dual router WAN edge.
To implement this design, the routers should connect via EtherChannel links to the distribution switch. These
EtherChannel links are configured as 802.1Q VLAN trunks, to support both a routed point-to-point link to allow
EIGRP routing with the distribution switch, and in the dual router design, to provide a transit network for direct
communication between the WAN routers.
Introduction
December 2013
11
Figure 7 - WAN remote site—Connection to distribution layer
WAN
WAN
802.1Q Trunk
(50)
802.1Q Trunk (yy, zz)
802.1Q Trunk (ww, xx)
VLAN 50 - Router 1 Link
802.1Q Trunk
(54, 99)
802.1Q Trunk (yy, zz)
VLAN 50 - Router 1 Link
VLAN 54 - Router 2 Link
VLAN 99 - Transit
2007
802.1Q Trunk (ww, xx)
802.1Q Trunk
(50, 99)
The distribution switch handles all access-layer routing, with VLANs trunked to access switches. No HSRP is
required when the design includes a distribution layer. A full distribution and access-layer design is shown in the
following figure.
Figure 8 - WAN remote site—Distribution and access layer (dual router)
WAN
802.1Q Trunk
(50, 99)
802.1Q Trunk
(ww, xx)
802.1Q Trunk
(54, 99)
802.1Q Trunk
(yy, zz)
VLAN ww - Data
VLAN yy - Data
VLAN xx - Voice
VLAN zz - Voice
No HSRP Required
Introduction
2144
VLAN 50 - Router 1 Link
VLAN 54 - Router 2 Link
VLAN 99 - Transit
December 2013
12
IP Multicast
IP Multicast allows a single IP data stream to be replicated by the infrastructure (routers and switches) and sent
from a single source to multiple receivers. IP Multicast is much more efficient than multiple individual unicast
streams or a broadcast stream that would propagate everywhere. IP telephony Music On Hold (MOH) and IP
video broadcast streaming are two examples of IP Multicast applications.
To receive a particular IP Multicast data stream, end hosts must join a multicast group by sending an Internet
Group Management Protocol (IGMP) message to their local multicast router. In a traditional IP Multicast design,
the local router consults another router in the network that is acting as a rendezvous point (RP) to map the
receivers to active sources so that they can join their streams.
The RP is a control-plane operation that should be placed in the core of the network or close to the IP Multicast
sources on a pair of Layer 3 switches or routers. IP Multicast routing begins at the distribution layer if the access
layer is Layer 2 and provides connectivity to the IP Multicast RP. In designs without a core layer, the distribution
layer performs the RP function.
This design is fully enabled for a single global scope deployment of IP Multicast. The design uses an Anycast RP
implementation strategy. This strategy provides load sharing and redundancy in Protocol Independent Multicast
sparse mode (PIM SM) networks. Two RPs share the load for source registration and the ability to act as hot
backup routers for each other.
The benefit of this strategy from the WAN perspective is that all IP routing devices within the WAN use an
identical configuration referencing the Anycast RPs. IP PIM SM is enabled on all interfaces including loopbacks,
VLANs, and subinterfaces.
Quality of Service
Most users perceive the network as just a transport utility mechanism to shift data from point A to point B as
fast as it can. Many sum this up as just “speeds and feeds.” While it is true that IP networks forward traffic on a
best-effort basis by default, this type of routing only works well for applications that adapt gracefully to variations
in latency, jitter, and loss. However networks are multiservice by design and support real-time voice and video as
well as data traffic. The difference is that real-time applications require packets to be delivered within specified
loss, delay, and jitter parameters.
In reality, the network affects all traffic flows and must be aware of end-user requirements and services being
offered. Even with unlimited bandwidth, time-sensitive applications are affected by jitter, delay, and packet loss.
Quality of service (QoS) enables a multitude of user services and applications to coexist on the same network.
Within the architecture, there are wired and wireless connectivity options that provide advanced classification,
prioritizing, queuing, and congestion mechanisms as part of the integrated QoS to help ensure optimal use of
network resources. This functionality allows for the differentiation of applications, ensuring that each has the
appropriate share of the network resources to protect the user experience and ensure the consistent operations
of business critical applications.
QoS is an essential function of the network infrastructure devices used throughout this architecture. QoS
enables a multitude of user services and applications, including real-time voice, high-quality video, and delaysensitive data to coexist on the same network. In order for the network to provide predictable, measurable, and
sometimes guaranteed services, it must manage bandwidth, delay, jitter, and loss parameters. Even if you do not
require QoS for your current applications, you can use QoS for management and network protocols to protect
the network functionality and manageability under normal and congested traffic conditions.
The goal of this design is to provide sufficient classes of service to allow you to add voice, interactive video,
critical data applications, and management traffic to the network, either during the initial deployment or later with
minimum system impact and engineering effort.
Introduction
December 2013
13
The QoS classifications in the following table are applied throughout this design. This table is included as a
reference.
Table 5 - QoS service class mappings
Introduction
Service class
Per-hop behavior
(PHB)
Differentiated
services code point
(DSCP)
IP precedence (IPP)
Class of service
(CoS)
Network layer
Layer 3
Layer 3
Layer 3
Layer 2
Network control
CS6
48
6
6
Telephony
EF
46
5
5
Signaling
CS3
24
3
3
Multimedia conferencing
AF41, 42, 43
34, 36, 38
4
4
Real-time interactive
CS4
32
4
4
Multimedia streaming
AF31, 32, 33
26, 28, 30
3
3
Broadcast video
CS5
40
4
4
Low-latency data
AF21, 22, 23
18, 20, 22
2
2
Operation, administration,
and maintenance (OAM)
CS2
16
2
2
Bulk data
AF11, 12, 13
10, 12, 14
1
1
Scavenger
CS1
8
1
1
Default “best effort”
DF
0
0
0
December 2013
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Deploying the WAN
Overall WAN Architecture Design Goals
IP Routing
The design has the following IP routing goals:
• Provide optimal routing connectivity from primary WAN-aggregation sites to all remote locations
• Isolate WAN routing topology changes from other portions of the network
• Ensure active/standby symmetric routing when multiple paths exist, for ease of troubleshooting and to
prevent oversubscription of IP telephony Call Admission Control (CAC) limits
• Provide site-site remote routing via the primary WAN-aggregation site (hub-and-spoke model)
• Permit optimal direct site-site remote routing when carrier services allow (spoke-to-spoke model)
• Support IP Multicast sourced from the primary WAN-aggregation site
At the WAN remote sites, there is no local Internet access for web browsing or cloud services. This model is
referred to as a centralized Internet model. It is worth noting that sites with Internet/DMVPN for backup transport
could potentially provide local Internet capability; however, for this design, only encrypted traffic to other DMVPN
sites is permitted to use the Internet link. In the centralized Internet model, a default route is advertised to the
WAN remote sites in addition to the internal routes from the data center and campus.
LAN Access
All remote sites are to support both wired LAN access.
High Availability
The network must tolerate single failure conditions including the failure of any single WAN transport link or any
single network device at the primary WAN-aggregation site.
• Remote sites classified as single-router, dual-link must be able tolerate the loss of either WAN transport.
• Remote sites classified as dual-router, dual-link must be able to tolerate the loss of either an edge router
or a WAN transport.
Path Selection Preferences
There are many potential traffic flows based on which WAN transports are in use and whether or not a remote
site is using a dual WAN transport.
The single WAN transport routing functions as follows.
MPLS VPN-connected site:
• Connects to a site on the same MPLS VPN—The optimal route is direct within the MPLS VPN (traffic is
not sent to the primary site).
• Connects to any other site—The route is through the primary site.
The use of the dual WAN transports is specifically tuned to behave in an active/standby manner. This type of
configuration provides symmetric routing, with traffic flowing along the same path in both directions. Symmetric
routing simplifies troubleshooting because bidirectional traffic flows always traverse the same links.
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The design assumes that one of the MPLS VPN WAN transports is designated as the primary transport, which is
the preferred path in most conditions.
MPLS VPN primary + MPLS VPN secondary dual-connected site:
• Connects to a site on the same MPLS VPN—The optimal route is direct within the MPLS VPN (traffic is
not sent to the primary site).
• Connects to any other site—The route is through the primary site.
Quality of Service (QoS)
The network must ensure that business applications perform across the WAN during times of network
congestion. Traffic must be classified and queued and the WAN connection must be shaped to operate within
the capabilities of the connection. When the WAN design uses a service provider offering with QoS, the WAN
edge QoS classification and treatment must align to the service provider offering to ensure consistent end-toend QoS treatment of traffic.
Design Parameters
This design guide uses certain standard design parameters and references various network infrastructure
services that are not located within the WAN. These parameters are listed in the following table.
Table 6 - Universal design parameters
Network service
IP address
Domain name
cisco.local
Active Directory, DNS server, DHCP server
10.4.48.10
Cisco Secure Access Control System (ACS)
10.4.48.15
Network Time Protocol (NTP) server
10.4.48.17
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Deploying an MPLS WAN
Design Overview
WAN-Aggregation—MPLS CE Routers
The MPLS WAN designs are intended to support up to 500 remote sites with a combined aggregate WAN
bandwidth of up to 1.0 Gbps. The most critical devices are the WAN routers that are responsible for reliable IP
forwarding and QoS. The amount of bandwidth required at the WAN-aggregation site determines which model of
router to use. The choice of whether to implement a single router or dual router is determined by the number of
carriers that are required in order to provide connections to all of the remote sites.
Cisco ASR 1000 Series Aggregation Services Routers represent the next-generation, modular, servicesintegrated Cisco routing platform. They are specifically designed for WAN aggregation, with the flexibility to
support a wide range of 3- to 16-mpps (millions of packets per second) packet-forwarding capabilities, 2.5- to
40-Gbps system bandwidth performance, and scaling.
The Cisco ASR 1000 Series is fully modular from both hardware and software perspectives, and the routers
have all the elements of a true carrier-class routing product that serves both enterprise and service-provider
networks.
This design uses the following routers as MPLS CE routers:
• Cisco ASR 1002-X router configured with an embedded service processor (ESP) default bandwidth of
5 Gbps upgradable with software licensing options to 10 Gbps, 20 Gbps, and 36 Gbps
• Cisco ASR 1002 router configured with an embedded service processor 5 (ESP5)
• Cisco ASR 1001 router fixed configuration with a 2.5 Gbps embedded service processor
• Cisco 3945 Integrated Services Router
• Cisco 3925 Integrated Services Router
All of the design models can be constructed using any of the MPLS CE routers listed in Table 7. You should
consider the following: the forwarding performance of the router using an Ethernet WAN deployment with broad
services enabled, the router’s alignment with the suggested design model, and the number of remote sites.
Table 7 - WAN aggregation—MPLS CE router options
Service
Cisco 3925
Cisco 3945
ASR 1001
ASR 1002
ASR 1002-X
Ethernet WAN with services
100 Mbps
150 Mbps
250 Mbps
500 Mbps
500Mbps-1.5Gbps
Software Redundancy
Option
None
None
Yes
Yes
Yes
Redundant power supply
Option
Option
Default
Default
Default
Supported Design Models
All
All
All
All
All
Suggested Design Model
MPLS Static
MPLS Static
MPLS Dynamic
Dual MPLS
Dual MPLS
Suggested Number of
Remote Sites
25
50
100
250
250+
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Remote Sites—MPLS CE Router Selection
The actual WAN remote-site routing platforms remain unspecified because the specification is tied closely to the
bandwidth required for a location and the potential requirement for the use of service module slots. The ability
to implement this solution with a variety of potential router choices is one of the benefits of a modular design
approach.
There are many factors to consider in the selection of the WAN remote-site routers. Among those, and key to
the initial deployment, is the ability to process the expected amount and type of traffic. You also need to make
sure that you have enough interfaces, enough module slots, and a properly licensed Cisco IOS Software image
that supports the set of features that is required by the topology. Cisco tested multiple integrated service router
models as MPLS CE routers, and the expected performance is shown in the following table.
Table 8 - WAN remote-site Cisco Integrated Services Router options
881V1
19412
2911
2921
2951
3925
3945
4451-X
8 Mbps
25 Mbps
35
Mbps
50
Mbps
75
Mbps
100
Mbps
150
Mbps
1 Gbps
On-board FE ports
1 (and 4-port
LAN switch)
0
0
0
0
0
0
0
On-board GE ports4
0
2
3
3
3
3
3
4
Service module slots5
0
0
1
1
2
2
4
2
Redundant power
supply option
No
No
No
No
No
Yes
Yes
Yes
Ethernet WAN with
services3
Notes:
1. The Cisco 881 Integrated Services Router is recommended for use at single-router, single-link remote
sites with VoIP requirements.
2. The 1941 is recommended for use at single-router, single-link remote sites.
3. The performance numbers are conservative numbers obtained when the router is passing IMIX traffic
with heavy services configured and the CPU utilization is under 75 percent.
4. A single-router, dual-link remote-site requires four router interfaces when using a port-channel to
connect to an access or distribution layer. Add the EHWIC-1GE-SFP-CU to the Cisco 2900 and 3900
Series Integrated Services Routers in order to provide the additional WAN-facing interface.
5. Not all service modules are supported in Cisco 4451-X ISR. Some service modules are double-wide.
The MPLS CE routers at the WAN remote sites connect in the same manner as the MPLS CE routers at the
WAN-aggregation site. The single link MPLS WAN remote site is the most basic of building blocks for any remote
location. You can use this design with the CE router connected directly to the access layer, or you can use it to
support a more complex LAN topology by connecting the CE router directly to a distribution layer.
The IP routing is straightforward and can be handled entirely by using static routes at the WAN-aggregation site
and static default routes at the remote site. However, there is significant value to configuring this type of site with
dynamic routing and this approach is used for the MPLS Dynamic and Dual MPLS designs.
Dynamic routing makes it easy to add or modify IP networks at the remote site because any changes are
immediately propagated to the rest of the network. MPLS VPN-connected sites require static routing in order to
be handled by the carrier, and any changes or modifications require a change request to the carrier.
The smaller scale MPLS Static design uses static routing and relies on the carrier to configure the additional
required static routes on the PE routers.
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Tech Tip
We recommend that you select the Dual MPLS or MPLS Dynamic designs if you intend
to use resilient WAN links or want to be able to modify your routing configuration
without carrier involvement.
Figure 9 - MPLS WAN remote site (single-router, single-link)
MPLS VPN
MPLS VPN
Static
Routing
Dynamic
Routing
MPLS Dynamic
MPLS Static
2124
Static
Routing
You can augment the basic single-link design by adding an alternate WAN transport that uses a secondary
MPLS carrier and either connects on the same router or on an additional router. By adding an additional link,
you provide the first level of high availability for the remote site. The router can automatically detect failure of
the primary link and reroute traffic to the secondary path. It is mandatory to run dynamic routing when there are
multiple paths and the Dual MPLS or MPLS Dynamic design models are used. The routing protocols are tuned to
ensure the proper path selection.
Figure 10 - MPLS WAN dual-carrier remote site (dual-link options)
MPLS VPN B
MPLS VPN A
Dual MPLS Design Model Only
MPLS VPN B
2125
MPLS VPN A
The dual-router, dual-link design continues to improve upon the level of high availability for the site. This design
can tolerate the loss of the primary router because the secondary router reroutes traffic via the alternate path.
Design Details
All WAN-aggregation MPLS CE routers connect to the same resilient switching device in the distribution layer.
All devices use EtherChannel connections consisting of two port bundles. This design provides both resiliency
and additional forwarding performance. You can accomplish additional forwarding performance by increasing the
number of physical links within an EtherChannel.
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WAN transport via Ethernet is the only media type tested and included in the configuration section. Other media
types are commonly used (such as T1/E1), and these technologies are reliable and well understood. Due to the
multiplicity of potential choices for transport, media type, and interface type, we decided to limit the focus of this
design guide. Documentation of additional variants is available in other guides.
MPLS VPNs require a link between a PE router and a CE router. The PE and CE routers are considered IP
neighbors across this link. CE routers are only able to communicate with other CE routers across the WAN via
intermediate PE routers.
Figure 11 - MPLS VPN (PE-CE connections)
MPLS Carrier
PE
Direct Adjacencies Only Between
CE and PE Routers
PE
CE
Direct Adjacencies Only Between
CE and PE Routers
2126
CE
Both the PE and CE routers are required to have sufficient IP-routing information in order to provide end-toend reachability. To maintain this routing information, you typically need to use a routing protocol; BGP is most
commonly used for this purpose. The various CE routers advertise their routes to the PE routers. The PE routers
propagate the routing information within the carrier network and in turn re-advertise the routes back to other CE
routers. This propagation of routing information is known as dynamic PE-CE routing and it is essential when any
sites have multiple WAN transports (often referred to as dual-homed or multi-homed). The Dual MPLS and MPLS
Dynamic designs use dynamic PE-CE routing with BGP.
Tech Tip
EIGRP and Open Shortest Path First (OSPF) Protocol are also effective as PE-CE
routing protocols, but may not be universally available across all MPLS VPN carriers.
Sites with only a single WAN transport (a single-homed site) do not require dynamic PE-CE routing, and can rely
on static routing because there is only a single path to any destination. This design recommends dynamic PE-CE
routing to provide consistency with configurations across both single-homed and dual-homed sites. This also
allows for easy transition from a single-homed to a dual-homed remote-site design by adding an additional link
to an existing remote site. A static routing option is also included to support smaller scale requirements that do
not require a dynamic routing protocol. Static routing is used in the MPLS Static design model.
Cisco did not test the PE routers, and their configurations are not included in this guide.
For an MPLS VPN WAN deployment, you need to install and configure MPLS CE routers at every location,
including the WAN-aggregation site, and at every MPLS WAN-connected remote site.
At the WAN-aggregation site, an MPLS CE router must be connected both to the distribution layer and to its
respective MPLS carrier. Multiple routing protocols (EIGRP and BGP) are used to exchange routing information,
and the routing protocol configurations are tuned from their default settings to influence traffic flows to their
desired behavior. The IP routing details for the single and dual MPLS carrier WAN-aggregation topology with
dynamic routing are shown in the following figure.
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Figure 12 - Dual MPLS and MPLS Dynamic designs—MPLS CE routing detail
WAN
Distribution
WAN
Distribution
EIGRP
EIGRP
MPLS CE
Routers
iBGP
eBGP
eBGP
MPLS A
MPLS B
eBGP
MPLS
Dual MPLS
MPLS Dynamic
2127
MPLS CE
Routers
EIGRP
The IP routing details for the single MPLS carrier WAN-aggregation topology with static routing are shown in the
following figure.
Figure 13 - MPLS Static Design—MPLS CE routing detail
WAN
Distribution
EIGRP
Static
Routing
MPLS CE
Router
MPLS
2128
Static
Routing
EIGRP
Cisco chose EIGRP as the primary routing protocol because it is easy to configure, does not require a large
amount of planning, has flexible summarization and filtering, and can scale to large networks. As networks grow,
the number of IP prefixes or routes in the routing tables grows as well. You should program IP summarization on
links where logical boundaries exist, such as distribution layer links to the wide area or to a core. By performing
IP summarization, you can reduce the amount of bandwidth, processor, and memory necessary to carry large
route tables, and reduce convergence time associated with a link failure.
In this design, EIGRP process 100 is the primary EIGRP process and is referred to as EIGRP-100.
EIGRP-100 is used at the WAN-aggregation site to connect to the primary site LAN distribution layer and at WAN
remote sites with dual WAN routers or with distribution-layer LAN topologies.
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BGP
Cisco chose BGP as the routing protocol for PE and CE routers to connect to the MPLS VPNs because it is
consistently supported across virtually all MPLS carriers. In this role, BGP is straightforward to configure and
requires little or no maintenance. BGP scales well and you can use it to advertise IP aggregate addresses for
remote sites.
To use BGP, you must select an Autonomous System Number (ASN). In this design, we use a private ASN
(65511) as designated by the Internet Assigned Numbers Authority (IANA). The private ASN range is 64512 to
65534.
A dual-carrier MPLS design requires an iBGP connection between the CE routers to properly retain routing
information for the remote sites.
Deployment Details
The procedures in this section provide examples for some settings. The actual settings and values that you use
are determined by your current network configuration.
Table 9 - Parameters used in the deployment examples
Hostname
Loopback IP Address
Port Channel IP Address
CE-ASR1002-1
10.4.32.241/32
10.4.32.2/30
CE-ASR1001-2
10.4.32.242/32
10.4.32.6/30
PROCESS
Configuring the MPLS CE Router
1. Configure the distribution switch
2. Configure the WAN Aggregation Platform
3. Configure connectivity to the LAN
4. Connect to MPLS PE router
5. Redistribute WAN routes into EIGRP
6. Configure BGP
Procedure 1
Configure the distribution switch
Reader Tip
This process assumes that the distribution switch has already been configured
following the guidance in the Campus Wired LAN Technology Design Guide. Only the
procedures required to support the integration of the WAN-aggregation router into the
deployment are included.
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The LAN distribution switch is the path to the organization’s main campus and data center. A Layer 3 portchannel interface connects to the distribution switch to the WAN-aggregation router and the internal routing
protocol peers across this interface.
Tech Tip
As a best practice, use the same channel numbering on both sides of the link where
possible.
Step 1: Configure the Layer 3 port-channel interface and assign the IP address.
interface Port-channel1
description CE-ASR1002-1
no switchport
ip address 10.4.32.1 255.255.255.252
ip pim sparse-mode
logging event link-status
carrier-delay msec 0
no shutdown
Step 2: Configure EtherChannel member interfaces.
Configure the physical interfaces to tie to the logical port-channel by using the channel-group command.
The number for the port-channel and channel-group must match. Not all router platforms can support Link
Aggregation Control Protocol (LACP) to negotiate with the switch, so you configure EtherChannel statically.
Also, apply the egress QoS macro that was defined in the platform configuration procedure to ensure traffic is
prioritized appropriately.
interface GigabitEthernet1/0/1
description CE-ASR1002-1 Gig0/0/0
!
interface GigabitEthernet2/0/1
description CE-ASR1002-1 Gig0/0/1
!
interface range GigabitEthernet1/0/1, GigabitEthernet2/0/1
no switchport
macro apply EgressQoS
carrier-delay msec 0
channel-group 1 mode on
logging event link-status
logging event trunk-status
logging event bundle-status
no shutdown
Step 3: Allow the routing protocol to form neighbor relationships across the port channel interface.
router eigrp 100
no passive-interface Port-channel1
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Step 4: On the distribution layer switch, configure the layer 3 interface connected to the LAN core to summarize
the WAN network range.
Tech Tip
It is a best practice to summarize IP routes from the WAN distribution layer towards the
core.
interface Port-channel38
description Link to C6500-VSS
ip summary-address eigrp 100 10.4.32.0 255.255.248.0
ip summary-address eigrp 100 10.4.128.0 255.255.240.0
ip summary-address eigrp 100 10.4.160.0 255.255.252.0
ip summary-address eigrp 100 10.5.0.0 255.255.0.0
Step 5: On the distribution layer switch, configure the layer 3 interfaces connected to the WAN aggregation
routers to summarize the WAN remote-site network range.
Tech Tip
It is a best practice to summarize IP routes from the WAN distribution layer towards the
MPLS WAN.
interface Port-channel1
description CE-ASR1002-1
ip summary-address eigrp 100 10.5.0.0 255.255.0.0
Repeat this step as needed for additional WAN aggregation routers.
Procedure 2
Configure the WAN Aggregation Platform
Within this design, there are features and services that are common across all WAN aggregation routers. These
are system settings that simplify and secure the management of the solution.
Step 1: Configure the device host name. This makes it easy to identify the device.
hostname CE-ASR1002-1
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Step 2: Configure local login and password.
The local login account and password provides basic access authentication to a router, which provides only
limited operational privileges. The enable password secures access to the device configuration mode. By
enabling password encryption, you prevent the disclosure of plain text passwords when viewing configuration
files.
username admin password c1sco123
enable secret c1sco123
service password-encryption
aaa new-model
Step 3: By default, HTTPS access to the router uses the enable password for authentication.
Step 4: (Optional) Configure centralized user authentication.
As networks scale in the number of devices to maintain it poses an operational burden to maintain local user
accounts on every device. A centralized authentication, authorization, and accounting (AAA) service reduces
operational tasks per device and provides an audit log of user access for security compliance and root cause
analysis. When AAA is enabled for access control, all management access to the network infrastructure devices
(SSH and HTTPS) is controlled by AAA.
TACACS+ is the primary protocol used to authenticate management logins on the infrastructure devices to
the AAA server. A local AAA user database is also defined in Step 2 on each network infrastructure device to
provide a fallback authentication source in case the centralized TACACS+ server is unavailable.
tacacs server TACACS-SERVER-1
address ipv4 10.4.48.15
key SecretKey
!
aaa group server tacacs+ TACACS-SERVERS
server name TACACS-SERVER-1
!
aaa authentication login default group TACACS-SERVERS local
aaa authorization exec default group TACACS-SERVERS local
aaa authorization console
ip http authentication aaa
Step 5: Configure device management protocols.
Secure HTTP (HTTPS) and Secure Shell (SSH) are secure replacements for the HTTP and Telnet protocols. They
use Secure Sockets Layer (SSL) and Transport Layer Security (TLS) to provide device authentication and data
encryption.
Secure management of the network device is enabled through the use of the SSH and HTTPS protocols. Both
protocols are encrypted for privacy and the unsecure protocols, Telnet and HTTP, are turned off.
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Specify the transport preferred none on vty lines to prevent errant connection attempts from the CLI prompt.
Without this command, if the ip name-server is unreachable, long timeout delays may occur for mistyped
commands.
ip domain-name cisco.local
ip ssh version 2
no ip http server
ip http secure-server
line vty 0 15
transport input ssh
transport preferred none
Step 6: Enable synchronous logging.
When synchronous logging of unsolicited messages and debug output is turned on, console log messages
are displayed on the console after interactive CLI output is displayed or printed. With this command, you can
continue typing at the device console when debugging is enabled.
line con 0
logging synchronous
Step 7: Enable Simple Network Management Protocol (SNMP). This allows the network infrastructure devices
to be managed by a Network Management System (NMS). SNMPv2c is configured both for a read-only and a
read-write community string.
snmp-server community cisco RO
snmp-server community cisco123 RW
Step 8: If operational support is centralized in your network, you can increase network security by using an
access list to limit the networks that can access your device. In this example, only devices on the 10.4.48.0/24
network will be able to access the device via SSH or SNMP.
access-list 55 permit 10.4.48.0 0.0.0.255
line vty 0 15
access-class 55 in
!
snmp-server community cisco RO 55
snmp-server community cisco123 RW 55
Tech Tip
If you configure an access-list on the vty interface you may lose the ability to use ssh
to login from one router to the next for hop-by-hop troubleshooting.
Step 9: Configure a synchronized clock.
The Network Time Protocol (NTP) is designed to synchronize a network of devices. An NTP network usually gets
its time from an authoritative time source, such as a radio clock or an atomic clock attached to a time server.
NTP then distributes this time across the organizations network.
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You should program network devices to synchronize to a local NTP server in the network. The local NTP server
typically references a more accurate clock feed from an outside source. By configuring console messages, logs,
and debug output to provide time stamps on output, you can cross-reference events in a network.
ntp server 10.4.48.17
!
clock timezone PST -8
clock summer-time PDT recurring
!
service timestamps debug datetime msec localtime
service timestamps log datetime msec localtime
Step 10: Configure an in-band management interface.
The loopback interface is a logical interface that is always reachable as long as the device is powered on and
any IP interface is reachable to the network. Because of this capability, the loopback address is the best way to
manage the switch in-band. Layer 3 process and features are also bound to the loopback interface to ensure
process resiliency.
The loopback address is commonly a host address with a 32-bit address mask. Allocate the loopback address
from the IP address block that the distribution switch summarizes to the rest of the network.
interface Loopback 0
ip address 10.4.32.241 255.255.255.255
ip pim sparse-mode
Step 11: Bind the device processes for SNMP, SSH, PIM, TACACS+ and NTP to the loopback interface address.
This provides optimal resiliency:
snmp-server trap-source Loopback0
ip ssh source-interface Loopback0
ip pim register-source Loopback0
ip tacacs source-interface Loopback0
ntp source Loopback0
Step 12: Configure IP unicast routing.
EIGRP is configured facing the LAN distribution or core layer. In this design, the port-channel interface and the
loopback must be EIGRP interfaces. The loopback may remain a passive interface. The network range must
include both interface IP addresses, either in a single network statement or in multiple network statements. This
design uses a best practice of assigning the router ID to a loopback address.
router eigrp 100
network 10.4.0.0 0.1.255.255
no auto-summary
passive-interface default
eigrp router-id 10.4.32.241
Step 13: Configure IP Multicast routing.
IP Multicast allows a single IP data stream to be replicated by the infrastructure (routers and switches) and sent
from a single source to multiple receivers. Using IP Multicast is much more efficient than using multiple individual
unicast streams or a broadcast stream that would propagate everywhere. IP Telephony MOH and IP Video
Broadcast Streaming are two examples of IP Multicast applications.
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In order to receive a particular IP Multicast data stream, end hosts must join a multicast group by sending an
IGMP message to their local multicast router. In a traditional IP Multicast design, the local router consults another
router in the network that is acting as an RP to map the receivers to active sources so they can join their streams.
This design, which is based on sparse mode multicast operation, uses Auto RP for a simple yet scalable way to
provide a highly resilient RP environment.
Enable IP Multicast routing on the platforms in the global configuration mode.
ip multicast-routing
If you are using a Cisco ASR 1000 Series router, the distributed keyword is required.
ip multicast-routing distributed
Step 14: Configure every Layer 3 switch and router to discover the IP Multicast RP with autorp. Use the ip pim
autorp listener command to allow for discovery across sparse mode links. This configuration provides for future
scaling and control of the IP Multicast environment and can change based on network needs and design.
ip pim autorp listener
Step 15: Enable sparse mode multicast operation for all Layer 3 interfaces in the network.
ip pim sparse-mode
Procedure 3
Configure connectivity to the LAN
Any links to adjacent distribution layers should be Layer 3 links or Layer 3 EtherChannels.
Step 1: Configure Layer 3 interface.
interface Port-channel1
ip address 10.4.32.2 255.255.255.252
ip pim sparse-mode
no shutdown
Step 2: Configure EtherChannel member interfaces.
Configure the physical interfaces to tie to the logical port-channel by using the channel-group command. The
number for the port-channel and channel-group must match. Not all router platforms can support LACP to
negotiate with the switch, so you configure EtherChannel statically.
interface GigabitEthernet0/0/0
description WAN-D3750X Gig1/0/1
!
interface GigabitEthernet0/0/1
description WAN-D3750X Gig2/0/1
!
interface range GigabitEthernet0/0/0, GigabitEthernet0/0/1
no ip address
channel-group 1
no shutdown
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Step 3: Configure the EIGRP interface.
Allow EIGRP to form neighbor relationships across the interface to establish peering adjacencies and exchange
route tables.
router eigrp 100
no passive-interface Port-channel1
Procedure 4
Connect to MPLS PE router
Step 1: Assign the interface bandwidth.
The bandwidth value should correspond to the actual interface speed. Or, if you are using a subrate service, use
the policed rate from the carrier.
The example shows a Gigabit interface (1000 Mbps) with a subrate of 300 Mbps.
interface GigabitEthernet0/0/3
bandwidth 300000
Tech Tip
Command reference:
bandwidth kbps
(300 Mbps = 300,000 kbps)
Step 2: Assign the IP address and netmask of the WAN interface.
The IP addressing used between CE and PE routers must be negotiated with your MPLS carrier. Typically a pointto-point netmask of 255.255.255.252 is used.
interface GigabitEthernet0/0/3
ip address 192.168.3.1 255.255.255.252
Step 3: Administratively enable the interface and disable CDP.
We do not recommend the use of CDP on external interfaces.
interface GigabitEthernet0/0/3
no cdp enable
no shutdown
Procedure 5
Redistribute WAN routes into EIGRP
The WAN-aggregation CE routers are configured either for dynamic routing with BGP or are statically routed. If
you have a remote-site design that includes sites with dual WAN links, or do not wish to have your MPLS carrier
make changes or modifications, then use the BGP option. This is the recommended approach.
If your remote-site design only uses single WAN links and you don’t anticipate adding or modifying IP networks
at the remote sites, then you can use the statically routed option. The MPLS carrier is responsible for configuring
static IP routing within the MPLS network.
Deploying an MPLS WAN
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29
Tech Tip
If you do not use dynamic routing with BGP, then the MPLS carrier must configure a
set of static routes on its PE routers for the WAN-aggregation site and for each of the
remote sites. Site-specific routing details must be shared with your MPLS carrier.
Option 1: BGP dynamic routing with MPLS carrier
Step 1: Redistribute BGP into EIGRP.
A default metric redistributes the BGP routes into EIGRP. By default, only the bandwidth and delay values are
used for metric calculation.
router eigrp [as number]
default-metric [bandwidth (Kbps)] [delay (usec)] 255 1 1500
redistribute bgp [BGP ASN]
Step 2: Configure route-map and inbound distribute-list for EIGRP.
This design uses mutual route redistribution: BGP routes are distributed into EIGRP and EIGRP routes are
distributed into BGP (covered inProcedure 6). It is important to tightly control how routing information is shared
between different routing protocols when you use this configuration; otherwise, you might experience route
flapping, where certain routes are repeatedly installed and withdrawn from the device routing tables. Proper
route control ensures the stability of the routing table.
An inbound distribute-list with a route-map is used to limit which routes are accepted for installation into the
route table. The WAN-aggregation MPLS CE routers are configured to only accept routes that do not originate
from the MPLS or DMVPN WAN sources. To accomplish this task, you must create a route-map that matches any
routes originating from the WAN indicated by a specific route tag. This method allows for dynamic identification
of the various WAN routes. BGP-learned routes are implicitly tagged with their respective source AS and other
WAN routes are explicitly tagged by their WAN-aggregation router (documented in a separate procedure). The
specific route tags in use are shown below.
Table 10 - Route tag information for WAN-aggregation MPLS CE routers
Tag
Route source
Tag method
action
65401
MPLS VPN A
implicit
block
65402
MPLS VPN B
implicit
block
300
Layer 2 WAN
explicit
accept
65512
DMVPN hub routers
explicit
block
This example includes all WAN route sources in the reference design. Depending on the actual design of your
network, you may need to block more tags.
It is important when creating the route-map that you include a permit statement at the end in order to permit the
installation of routes with non-matching tags.
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Tech Tip
If you configure mutual route redistribution without proper matching, tagging, and
filtering, route-flapping may occur, which can cause instability.
route-map BLOCK-TAGGED-ROUTES deny 10
match tag 65401 65402 65512
!
route-map BLOCK-TAGGED-ROUTES permit 20
!
router eigrp 100
distribute-list route-map BLOCK-TAGGED-ROUTES in
default-metric 100000 100 255 1 1500
redistribute bgp 65511
Option 2: Static routing with service provider
Step 1: Configure static routes to remote sites’ LANs on the WAN-aggregation CE router. It is a best practice to
summarize the remote-site network ranges into a single route when possible.
ip route 10.5.0.0 255.255.0.0 192.168.3.2
Step 2: It is desirable to advertise a route for the MPLS PE-CE links, which includes the CE routers’ WAN
interfaces, so you can use this to determine router reachability, for troubleshooting. It is a best practice to
summarize the PE-CE link ranges into a single route when possible.
ip route 192.168.3.0 255.255.255.0 192.168.3.2
Step 3: Configure routes to the remote-site router loopback addresses. A single summary route for the loopback
range may be used when possible.
ip route 10.255.251.0 255.255.255.0 192.168.3.2
Step 4: Configure EIGRP to advertise the remote-site static routes. A default metric redistributes these routes
into EIGRP. By default, only the bandwidth and delay values are used for metric calculation.
router eigrp [as number]
default-metric [bandwidth (Kbps)] [delay (usec)] 255 1 1500
redistribute static
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Procedure 6
Configure BGP
If you are using BGP dynamic routing with the MPLS carrier, complete this procedure.
Step 1: Enable BGP.
To complete this step, you must use a BGP ASN. You can consult with your MPLS carrier on the requirements
for the ASN, but you may be permitted to use a private ASN as designated by IANA. The private ASN range is
64512 to 65534.
router bgp 65511
no synchronization
bgp router-id 10.4.32.241
bgp log-neighbor-changes
no auto-summary
Step 2: Configure eBGP.
You must configure BGP with the MPLS carrier PE device. The MPLS carrier must provide their ASN (the ASN
in the previous step is the ASN identifying your site). Because the carrier PE router uses a different ASN, this
configuration is considered an external BGP (eBGP) connection.
The CE router advertises only network routes to the PE via BGP when:
• The route is specified in network statements and is present in the local routing table.
• The route is redistributed into BGP.
It is desirable to advertise a route for the PE-CE link, so you should include this network in a network statement.
You can use this to determine router reachability, for troubleshooting.
router bgp 65511
network 192.168.3.0 mask 255.255.255.252
neighbor 192.168.3.2 remote-as 65401
Step 3: Redistribute EIGRP into BGP.
All EIGRP routes learned by the CE router, including routes from the core and for other WAN sites, should be
advertised into the WAN. It is most efficient if you summarize these routes before they are advertised to the CE
router.
Because BGP does not propagate a default route via redistribution, you must explicitly specify 0.0.0.0 in a
network statement.
router bgp 65511
network 0.0.0.0
redistribute eigrp 100
Step 4: If you have dual MPLS carriers, configure a BGP link between the CE routers.
Because the CE routers are using the same ASN, this configuration is considered an internal BGP (iBGP)
connection. This design uses iBGP peering using device loopback addresses, which requires the update-source
and next-hop-self-configuration options.
router bgp 65511
neighbor 10.4.32.242 remote-as 65511
neighbor 10.4.32.242 update-source Loopback0
neighbor 10.4.32.242 next-hop-self
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Configuring the Remote-Site MPLS CE Router
1. Configure the WAN Remote Router
2. Connect to the MPLS PE Router
PROCESS
3. Configure WAN routing
4. Connect router to access-layer switch
5. Configure access-layer routing
6. Configure remote-site DHCP
7. Configure access-layer HSRP
8. Configure the transit network
9. Configure EIGRP (LAN side)
10.Configure BGP
11.Enable Enhanced Object Tracking
Use this process for the configuration of any of the following:
• MPLS CE router for an MPLS WAN remote site (single router, single link)
• MPLS WAN Dual Carrier remote site
Use the following procedures when performing the initial configuration of a dual-connected MPLS CE in the
single-router, dual-link design or for configuring the first router of the dual-router, dual-link design.
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The following flowchart provides details about the configuration process for a remote-site MPLS CE router.
Figure 14 - Remote-site MPLS CE router configuration flowchart
Remote-Site
MPLS CE Router
Single Router, Single Link
Remote-Site MPLS CE
Router Configuration
Procedures
Remote-Site
MPLS CE Router
Dual Router, Dual Link
(1st Router)
Remote-Site
MPLS CE Router
Single Router, Dual Link
1. Configure the WAN Remote Router
2. Connect to MPLS PE Router
3. Configure WAN Routing
Distribution
Layer
Design?
NO
YES
4. Connect
nnect Router to Access Layer Switch
Remote-Site
Router to
Distribution Layer
Procedures
1. Connect to Distribution Layer
2. Configure EIGRP (LAN Side)
NO
Dual Router
Design?
YES
Dual Router
Design?
5. Configure Access Layer Routing
6. Configure Remote-Site DHCP (Optional)
YES
NO
RP
7. Configure Access Layer HSRP
3. Configure Transit Network
3
8. Configure Transit Network
Router
4. Configure BGP for Dual Rout
9. Configure EIGRP (LAN Side))
11. Enable
ble Enhanced O
bject Tra
acking
Object
Tracking
MPLS CE Spoke Router
Configuration Complete
Deploying an MPLS WAN
e Second
Configure
Remote-Site Router
MPLS CE Router
Configuration Complete
Configure Second
C
Remote-Site Router
2129
uter
10. Configure BGP for Dual Router
December 2013
34
Procedure 1
Configure the WAN Remote Router
Within this design, there are features and services that are common across all WAN remote-site routers. These
are system settings that simplify and secure the management of the solution.
Step 1: Configure the device host name to make it easy to identify the device.
hostname [hostname]
Step 2: Configure the local login and password.
The local login account and password provides basic access authentication to a router that provides only limited
operational privileges. The enable password secures access to the device configuration mode. By enabling
password encryption, you prevent the disclosure of plain text passwords when viewing configuration files.
username admin password c1sco123
enable secret c1sco123
service password-encryption
aaa new-model
Step 3: By default, https access to the router uses the enable password for authentication.
Step 4: (Optional) Configure centralized user authentication.
As networks scale in the number of devices to maintain, it can be an operational burden to maintain local user
accounts on every device. A centralized authentication, authorization, and accounting (AAA) service reduces
operational tasks per device and provides an audit log of user access for security compliance and root cause
analysis. When AAA is enabled for access control, all management access to the network infrastructure devices
(SSH and HTTPS) is controlled by AAA.
TACACS+ is the primary protocol used to authenticate management logins on the infrastructure devices to the
AAA server. A local AAA user database is also defined in Step 2 on each network infrastructure device in order
to provide a fallback authentication source in case the centralized TACACS+ server is unavailable.
tacacs server TACACS-SERVER-1
address ipv4 10.4.48.15
key SecretKey
!
aaa group server tacacs+ TACACS-SERVERS
server name TACACS-SERVER-1
!
aaa authentication login default group TACACS-SERVERS local
aaa authorization exec default group TACACS-SERVERS local
aaa authorization console
ip http authentication aaa
Step 5: Configure device management protocols.
Secure HTTP (HTTPS) and Secure Shell (SSH) are secure replacements for the HTTP and Telnet protocols. They
use Secure Sockets Layer (SSL) and Transport Layer Security (TLS) to provide device authentication and data
encryption.
Secure management of the network device is enabled through the use of the SSH and HTTPS protocols. Both
protocols are encrypted for privacy and the unsecure protocols, Telnet and HTTP, are turned off.
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Specify the transport preferred none on vty lines to prevent errant connection attempts from the CLI prompt.
Without this command, if the ip name-server is unreachable, long timeout delays may occur for mistyped
commands.
ip domain-name cisco.local
ip ssh version 2
no ip http server
ip http secure-server
line vty 0 15
transport input ssh
transport preferred none
Step 6: Enable synchronous logging.
When synchronous logging of unsolicited messages and debug output is turned on, console log messages
are displayed on the console after interactive CLI output is displayed or printed. With this command, you can
continue typing at the device console when debugging is enabled.
line con 0
logging synchronous
Step 7: Enable Simple Network Management Protocol (SNMP). This allows the network infrastructure devices to
be managed by a Network Management System (NMS). Configure SNMPv2c both for a read-only and a readwrite community string.
snmp-server community cisco RO
snmp-server community cisco123 RW
Step 8: If your network operational support is centralized, you can increase network security by using an access
list to limit the networks that can access your device. In this example, only devices on the 10.4.48.0/24 network
will be able to access the device via SSH or SNMP.
access-list 55 permit 10.4.48.0 0.0.0.255
line vty 0 15
access-class 55 in
!
snmp-server community cisco RO 55
snmp-server community cisco123 RW 55
Tech Tip
If you configure an access-list on the vty interface you may lose the ability to use ssh
to log in from one router to the next for hop-by-hop troubleshooting.
Step 9: Configure a synchronized clock.
The Network Time Protocol (NTP) is designed to synchronize a network of devices. An NTP network usually gets
its time from an authoritative time source, such as a radio clock or an atomic clock attached to a time server.
NTP then distributes this time across the organization’s network.
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You should program network devices to synchronize to a local NTP server in the network. The local NTP server
typically references a more accurate clock feed from an outside source. By configuring console messages, logs,
and debug output to provide time stamps on output, you can cross-reference events in a network.
ntp server 10.4.48.17
ntp update-calendar
!
clock timezone PST -8
clock summer-time PDT recurring
!
service timestamps debug datetime msec localtime
service timestamps log datetime msec localtime
Step 10: Configure an in-band management interface.
The loopback interface is a logical interface that is always reachable as long as the device is powered on and
any IP interface is reachable to the network. Because of this capability, the loopback address is the best way to
manage the switch in-band. Layer 3 process and features are also bound to the loopback interface to ensure
process resiliency.
The loopback address is commonly a host address with a 32-bit address mask. Allocate the loopback address
from a unique network range that is not part of any other internal network summary range.
interface Loopback 0
ip address [ip address] 255.255.255.255
ip pim sparse-mode
Step 11: Bind the device processes for SNMP, SSH, PIM, TACACS+ and NTP to the loopback interface address
for optimal resiliency:
snmp-server trap-source Loopback0
ip ssh source-interface Loopback0
ip pim register-source Loopback0
ip tacacs source-interface Loopback0
ntp source Loopback0
Step 12: Configure IP Multicast routing.
IP Multicast allows a single IP data stream to be replicated by the infrastructure (routers and switches) and sent
from a single source to multiple receivers. Using IP Multicast is much more efficient than multiple individual
unicast streams or a Broadcast stream that would propagate everywhere. IP Telephony MOH and IP Video
Broadcast Streaming are two examples of IP Multicast applications.
To receive a particular IP Multicast data stream, end hosts must join a multicast group by sending an IGMP
message to their local multicast router. In a traditional IP Multicast design, the local router consults another router
in the network that is acting as an RP to map the receivers to active sources so they can join their streams.
In this design, which is based on sparse mode multicast operation, Auto RP is used to provide a simple yet
scalable way to provide a highly resilient RP environment.
Enable IP Multicast routing on the platforms in the global configuration mode.
ip multicast-routing
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Step 13: Configure every Layer 3 switch and router to discover the IP Multicast RP with autorp. Use the ip pim
autorp listener command to allow for discovery across sparse mode links. This configuration provides for future
scaling and control of the IP Multicast environment and can change based on network needs and design.
ip pim autorp listener
Step 14: Enable sparse mode multicast operation for all Layer 3 interfaces in the network.
ip pim sparse-mode
Procedure 2
Connect to the MPLS PE Router
Step 1: Assign the interface bandwidth.
The bandwidth value should correspond to the actual interface speed. Or, if you are using a subrate service, you
should use the policed rate from the carrier.
The example shows a Gigabit interface (1000 Mbps) with a subrate of 10 Mbps.
interface [interface type] [number]
bandwidth [bandwidth (kbps)]
Tech Tip
Command Reference:
bandwidth kbps
10 Mbps = 10,000 kbps
Step 2: Assign the IP address and netmask of the WAN interface.
The IP addressing used between CE and PE routers must be negotiated with your MPLS carrier. Typically, you’d
use a point-to-point netmask of 255.255.255.252.
interface [interface type] [number]
ip address [IP address] [netmask]
Step 3: Administratively enable the interface and disable CDP. The use of CDP on external interfaces is not
recommended.
interface [interface type] [number]
no cdp enable
no shutdown
Example
interface GigabitEthernet0/0
bandwidth 10000
ip address 192.168.3.9 255.255.255.252
no cdp enable
no shutdown
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Procedure 3
Configure WAN routing
The remote-site CE routers are configured either for dynamic routing with BGP or are statically routed. If you
have a remote-site design that includes sites with dual WAN links or you do not want to have your MPLS carrier
make changes or modifications, use the BGP option. This is the recommended approach, and assumes that the
WAN-aggregation CE router has already been configured for BGP.
If your remote-site design only uses single WAN links and you don’t anticipate adding or modifying IP networks
at the remote site, then you can use the statically routed option. The MPLS carrier is responsible for configuring
static IP routing within the MPLS network.
Tech Tip
If you do not use dynamic routing with BGP, then the MPLS carrier must configure a
set of static routes on its PE routers for the WAN-aggregation site and for each of the
remote sites. Site-specific routing details must be shared with your MPLS carrier.
Option 1: BGP dynamic routing with MPLS carrier
Step 1: Enable BGP.
To complete this step, a BGP ASN is required. You might be able to reuse the same value used on the MPLS
VPN CE from the WAN-aggregation site. Consult with your MPLS carrier on the requirements for the ASN.
router bgp 65511
no synchronization
bgp router-id [IP address of Loopback0]
bgp log-neighbor-changes
no auto-summary
Step 2: Configure eBGP.
Configure BGP with the MPLS carrier PE device. The MPLS carrier must provide their ASN (the ASN in
the previous step is the ASN identifying your site). Because the carrier PE router uses a different ASN, this
configuration is considered an external BGP (eBGP) connection.
The CE router advertises only network routes to the PE via BGP in the following cases:
• The route is specified in network statements and is present in the local routing table.
• The route is redistributed into BGP (not applicable in the remote-site use case).
It is desirable to advertise a route for the PE-CE link, so you should include this network in a network statement.
You can use this to determine router reachability, for troubleshooting. Similarly, you must configure BGP to
advertise the loopback network for the router.
Deploying an MPLS WAN
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You must advertise the remote-site LAN networks. The IP assignment for the remote sites was designed so that
all of the networks in use can be summarized within a single aggregate route. The aggregate address configured
below suppresses the more specific routes. If any LAN network is present in the route table, the aggregate
is advertised to the MPLS PE, which offers a measure of resiliency. If the various LAN networks cannot be
summarized, you must list each individually. You must add a separate network statement for the loopback
address.
router bgp 65511
network [PE-CE link network] mask [PE-CE link netmask]
network [Loopback network] mask 255.255.255.255
network [DATA network] mask [netmask]
network [VOICE network] mask [netmask]
aggregate-address [summary IP address] [summary netmask] summary-only
neighbor [IP address of PE] remote-as [carrier ASN]
Example
router bgp 65511
no synchronization
bgp router-id 10.255.251.206
bgp log-neighbor-changes
network 192.168.3.8 mask 255.255.255.252
network 10.255.251.206 mask 255.255.255.255
network 10.5.12.0 mask 255.255.255.0
network 10.5.13.0 mask 255.255.255.0
aggregate-address 10.5.8.0 255.255.248.0 summary-only
neighbor 192.168.3.10 remote-as 65401
no auto-summary
Option 2: Static routing with service provider
This option has remote sites using static routing to the MPLS WAN to forward all traffic to the WAN-aggregation
site.
Step 1: Enter a default route for traffic forwarded to the WAN-aggregation site.
ip route 0.0.0.0 0.0.0.0 192.168.3.10
Step 2: For the MPLS carrier for each remote site, provide the remote-site specific IP range and the chosen
loopback IP address for the router. This properly configures the static routes to the remote site.
Tech Tip
For each remote site with static routing, the WAN-aggregation CE router must have a
corresponding static host route for that site’s loopback address.
Deploying an MPLS WAN
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Procedure 4
Connect router to access-layer switch
Reader Tip
This guide includes only the additional steps to complete the distribution-layer
configuration. For complete access-layer configuration details, see the Campus Wired
LAN Technology Design Guide.
If you are using a remote-site distribution layer, skip to the “Deploying a WAN Remote-Site Distribution Layer”
chapter of this guide.
Layer 2 EtherChannels are used to interconnect the CE router to the access layer in the most resilient method
possible. If your access-layer device is a single, fixed-configuration switch, a simple Layer 2 trunk between the
router and switch is used.
In the access-layer design, the remote sites use collapsed routing, with 802.1Q trunk interfaces to the LAN
access layer. The VLAN numbering is locally significant only.
Option 1: Layer 2 EtherChannel from router to access-layer switch
Step 1: Configure port-channel interface on the router.
interface Port-channel1
description EtherChannel link to RS206-A2960S
no shutdown
Step 2: Configure EtherChannel member interfaces on the router.
Configure the physical interfaces to tie to the logical port-channel by using the channel-group command. The
number for the port-channel and channel-group must match. Not all router platforms can support LACP to
negotiate with the switch, so you configure EtherChannel statically.
interface GigabitEthernet0/1
description RS206-A2960S Gig1/0/24
!
interface GigabitEthernet0/2
description RS206-A2960S Gig2/0/24
!
interface range GigabitEthernet0/1, GigabitEthernet0/2
no ip address
channel-group 1
no shutdown
Step 3: Configure EtherChannel member interfaces on the access-layer switch.
Connect the router EtherChannel uplinks to separate switches in the access layer switch stack, or in the case of
the Cisco Catalyst 4507R+E distribution layer, to separate redundant modules for additional resiliency.
The physical interfaces that are members of a Layer 2 EtherChannel are configured prior to configuring the
logical port-channel interface. Doing the configuration in this order allows for minimal configuration and reduces
errors because most of the commands entered to a port-channel interface are copied to its members’ interfaces
and do not require manual replication.
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Configure two physical interfaces to be members of the EtherChannel. Also, apply the egress QoS macro that
was defined in the LAN switch platform configuration procedure to ensure traffic is prioritized appropriately.
Not all connected router platforms can support LACP to negotiate with the switch, so you configure EtherChannel
statically.
interface GigabitEthernet1/0/24
description Link to RS206-3925-1 Gig0/1
interface GigabitEthernet2/0/24
description Link to RS206-3925-1 Gig0/2
!
interface range GigabitEthernet1/0/24, GigabitEthernet2/0/24
switchport
macro apply EgressQoS
channel-group 1 mode on
logging event link-status
logging event trunk-status
logging event bundle-status
Step 4: Configure EtherChannel trunk on the access-layer switch.
Use an 802.1Q trunk for the connection, which allows the router to provide the Layer 3 services to all the VLANs
defined on the access-layer switch. Prune the VLANs allowed on the trunk to only the VLANs that are active on
the access-layer switch. When using EtherChannel, the interface type is port-channel, and the number must
match the channel group configured in Step 3. Set DHCP Snooping and Address Resolution Protocol (ARP)
inspection to trust.
interface Port-channel1
description EtherChannel link to RS206-3925-1
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 64,69
switchport mode trunk
ip arp inspection trust
spanning-tree portfast trunk
ip dhcp snooping trust
no shutdown
The Cisco Catalyst 2960-S Series and 4500 Series switches do not require the switchport trunk encapsulation
dot1q command.
Option 2: Layer 2 trunk from router to access-layer switch
Step 1: Enable the physical interface on the router.
interface GigabitEthernet0/2
description RS202-A3560X Gig1/0/24
no ip address
no shutdown
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Step 2: Configure the trunk on the access-layer switch.
Use an 802.1Q trunk for the connection, which allows the router to provide the Layer 3 services to all the VLANs
defined on the access-layer switch. Prune the VLANs allowed on the trunk to only the VLANs that are active on
the access-layer switch. Set DHCP Snooping and Address Resolution Protocol (ARP) inspection to trust.
interface GigabitEthernet1/0/24
description Link to RS201-2911 Gig0/2
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 64,69
switchport mode trunk
ip arp inspection trust
spanning-tree portfast trunk
macro apply EgressQoS
logging event link-status
logging event trunk-status
ip dhcp snooping trust
no shutdown
The Cisco Catalyst 2960-S Series and 4500 Series switches do not require the switchport trunk encapsulation
dot1q command.
Option 3: Layer 2 trunk from Cisco 881 router to access-layer switch
This option uses a single Ethernet connection in order to connect the remote-site Cisco 881 Integrated Services
Router to a single-member access switch. This option differs significantly from the previous options because an
embedded Ethernet switch provides the LAN connectivity of the Cisco 881 router.
Step 1: Configure necessary VLANs on the embedded switch of the remote-site router.
vlan 64
name Wired-Data
vlan 69
name Wired-Voice
vlan 999
name Native
Step 2: Configure the remote-site router’s connection to the remote-site Ethernet switch.
interface FastEthernet0
switchport trunk native vlan 999
switchport trunk allowed vlan 1,2,64,69,1002-1005
switchport mode trunk
no ip address
no shutdown
Tech Tip
The embedded switch on the Cisco 881 Integrated Services Router requires that
the default VLANs be allowed on trunks. To maintain security and configuration
consistency, these VLANs (1, 2, 1002, 1003, 1004, and 1005) are pruned on the
access-switch side of the trunk.
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Step 3: Configure the trunk on the access-layer switch.
Use an 802.1Q trunk for the connection. This allows the router to provide the Layer 3 services to all the VLANs
defined on the access-layer switch. Prune the VLANs allowed on the trunk to only the VLANs that are active on
the access switch, and then set DHCP Snooping and Address Resolution Protocol (ARP) inspection to trust.
interface GigabitEthernet1/0/24
description Link to RS4-881 Fast0
switchport trunk native vlan 999
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 64,69
switchport mode trunk
ip arp inspection trust
macro apply EgressQoS
logging event link-status
logging event trunk-status
ip dhcp snooping trust
no shutdown
The Cisco Catalyst 2960-S Series and 4500 Series switches do not require the switchport trunk encapsulation
dot1q command.
Procedure 5
Configure access-layer routing
Option 1: Layer 2 EtherChannel or Layer 2 trunk
Step 1: Create subinterfaces and assign VLAN tags.
After you have enabled the physical interface or port-channel, you can map the appropriate data or voice
subinterfaces to the VLANs on the LAN switch. The subinterface number does not need to equate to the 802.1Q
tag, but making them the same simplifies the overall configuration. The subinterface portion of the configuration
should be repeated for all data or voice VLANs.
interface [type][number].[sub-interface number]
encapsulation dot1Q [dot1q VLAN tag]
Step 2: Configure IP settings for each subinterface.
This design uses an IP addressing convention with the default gateway router assigned an IP address and IP
mask combination of N.N.N.1 255.255.255.0 where N.N.N is the IP network and 1 is the IP host.
When using a centralized DHCP server, routers with LAN interfaces connected to a LAN using DHCP for endstation IP addressing must use an IP helper. This is the preferred method. An alternate option for local DHCP
server configuration is shown in the following procedure.
If the remote-site router is the first router of a dual-router design, then HSRP is configured at the access layer.
This requires a modified IP configuration on each subinterface.
interface [type][number].[sub-interface number]
description [usage]
ip address [LAN network 1] [LAN network 1 netmask]
ip helper-address 10.4.48.10
ip pim sparse-mode
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Option 2: Layer 2 trunk from Cisco 881 router to access-layer switch
Step 1: Configure IP settings for each subinterface.
This design uses an IP addressing convention with the default gateway router assigned an IP address and IP
mask combination of N.N.N.1 255.255.255.0 where N.N.N is the IP network and 1 is the IP host.
When using a centralized DHCP server, routers with LAN interfaces connected to a LAN using DHCP for endstation IP addressing must use an IP helper. This is the preferred method. An alternate option for local DHCP
server configuration is shown in the following procedure.
interface [VLAN number]
description [usage]
ip address [LAN network 1] [LAN network 1 netmask]
ip helper-address 10.4.48.10
ip pim sparse-mode
Example: Layer 2 EtherChannel
interface Port-channel1
no ip address
no shutdown
!
interface Port-channel1.64
description Data
encapsulation dot1Q 64
ip address 10.5.12.1 255.255.255.0
ip helper-address 10.4.48.10
ip pim sparse-mode
!
interface Port-channel1.69
description Voice
encapsulation dot1Q 69
ip address 10.5.13.1 255.255.255.0
ip helper-address 10.4.48.10
ip pim sparse-mode
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Example: Layer 2 Link
interface GigabitEthernet0/2
no ip address
no shutdown
!
interface GigabitEthernet0/2.64
description Data
encapsulation dot1Q 64
ip address 10.5.12.1 255.255.255.0
ip helper-address 10.4.48.10
ip pim sparse-mode
!
interface GigabitEthernet0/2.69
description Voice
encapsulation dot1Q 69
ip address 10.5.13.1 255.255.255.0
ip helper-address 10.4.48.10
ip pim sparse-mode
Example: Layer 2 Link from Cisco 881 ISR
interface Vlan64
description Data
ip address 10.5.28.1 255.255.255.0
ip helper-address 10.4.48.10
ip pim sparse-mode
!
interface Vlan69
description Voice
ip address 10.5.29.1 255.255.255.0
ip helper-address 10.4.48.10
ip pim sparse-mode
Procedure 6
Configure remote-site DHCP
(Optional)
The previous procedure assumes the DHCP service has been configured centrally and uses the ip helperaddress command to forward DHCP requests to the centralized DHCP server.
If you choose to run a local DHCP server on the remote-site router instead of centralizing the DHCP service,
complete this procedure. This procedure uses a local DHCP service on the router in order to assign basic
network configuration for IP phones, wireless access points, users’ laptop and desktop computers, and other
endpoint devices.
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Tech Tip
If you intend to use a dual-router remote-site design, you should use a resilient DHCP
solution, such as a centralized DHCP server. Options for resilient DHCP at the remotesite include using IOS on a distribution-layer switch stack or implementing a dedicated
DHCP server solution.
Step 1: Remove the previously configured ip helper-address commands for any interface that uses a local
DHCP server.
Step 2: Configure a DHCP scope for data endpoints, excluding DHCP assignment for the first 19 addresses in
the subnet.
ip dhcp excluded-address 10.5.4.1 10.11.4.19
ip dhcp pool DHCP-Wired-Data
network 10.5.4.0 255.255.255.0
default-router 10.5.4.1
domain-name cisco.local
dns-server 10.4.48.10
Step 3: Configure a DHCP scope for voice endpoints, excluding DHCP assignment for the first 19 addresses in
the subnet.
Step 4: Voice endpoints require an option field to tell them where to find their initial configuration. Different
vendors use different option fields, so the number may vary based on the voice product you choose (for
example, Cisco uses DHCP option 150).
ip dhcp excluded-address 10.5.5.1 10.11.5.19
ip dhcp pool DHCP-Wired-Voice
network 10.5.5.0 255.255.255.0
default-router 10.5.5.1
domain-name cisco.local
dns-server 10.4.48.10
Procedure 7 through Procedure 11 are only relevant for the dual-router design.
Procedure 7
Configure access-layer HSRP
If you are using a dual-router design, complete this procedure.
You need to configure HSRP in order to enable the use of a virtual IP (VIP) address as a default gateway that is
shared between two routers. The HSRP active router is the MPLS CE router connected to the primary MPLS
carrier, and the HSRP standby router is the router connected to the secondary MPLS carrier or backup link.
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In this procedure, you configure the HSRP active router with a standby priority that is higher than the HSRP
standby router. The router with the higher standby priority value is elected as the HSRP active router. The
preempt option allows a router with a higher priority to become the HSRP active, without waiting for a scenario
where there is no router in the HSRP active state. The relevant HSRP parameters for the router configuration are
shown in the following table.
Table 11 - WAN remote-site HSRP parameters (dual-router design)
Router
HSRP role
Virtual IP
address (VIP)
Real IP address
HSRP priority
PIM DR priority
MPLS CE (primary)
Active
.1
.2
110
110
MPLS CE (secondary) or
DMVPN spoke
Standby
.1
.3
105
105
The assigned IP addresses override those configured in the previous procedure, so the default gateway IP
address remains consistent across locations with single or dual routers.
The dual-router access-layer design requires a modification for resilient multicast. The PIM designated router
(DR) should be on the HSRP active router. The DR is normally elected based on the highest IP address, and it has
no awareness of the HSRP configuration. In this design, assigning the HSRP active router a lower real IP address
than the HSRP standby router requires a modification to the PIM configuration. You can influence the PIM DR
election by explicitly setting the DR priority on the LAN-facing subinterfaces for the routers.
Tech Tip
The HSRP priority and PIM DR priority are shown in the previous table to be the same
value; however, you are not required to use identical values.
Step 1: Configure HSRP.
interface [type][number].[sub-interface number]
ip address [LAN network 1 address] [LAN network 1 netmask]
ip pim dr-priority 110
standby version 2
standby 1 ip [LAN network 1 gateway address]
standby 1 priority 110
standby 1 preempt
standby 1 authentication md5 key-string c1sco123
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Step 2: Repeat this procedure for all data or voice subinterfaces.
Example: Layer 2 link
interface GigabitEthernet0/2
no ip address
no shutdown
!
interface GigabitEthernet0/2.64
description Data
encapsulation dot1Q 64
ip address 10.5.12.2 255.255.255.0
ip helper-address 10.4.48.10
ip pim dr-priority 110
ip pim sparse-mode
standby version 2
standby 1 ip 10.5.12.1
standby 1 priority 110
standby 1 preempt
standby 1 authentication md5 key-string c1sco123
!
interface GigabitEthernet0/2.69
description Voice
encapsulation dot1Q 69
ip address 10.5.13.2 255.255.255.0
ip helper-address 10.4.48.10
ip pim dr-priority 110
ip pim sparse-mode
standby version 2
standby 1 ip 10.5.13.1
standby 1 priority 110
standby 1 preempt
standby 1 authentication md5 key-string c1sco123
Procedure 8
Configure the transit network
If you are using a dual-router design, complete this procedure.
The transit network is configured between the two routers. This network is used for router-router communication
and to avoid hairpinning. The transit network should use an additional subinterface on the router interface that is
already being used for data or voice.
There are no end stations connected to this network, so HSRP and DHCP are not required.
Step 1: On the primary MPLS CE router, configure the transit network interface.
interface [type][number].[sub-interface number]
encapsulation dot1Q [dot1q VLAN tag]
ip address [transit net address] [transit net netmask]
ip pim sparse-mode
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Example
interface GigabitEthernet0/2.99
description Transit Net
encapsulation dot1Q 99
ip address 10.5.8.1 255.255.255.252
ip pim sparse-mode
Step 2: On the access-layer switch, add the transit network VLAN.
vlan 99
name Transit-net
Step 3: Add the transit network VLAN to the existing access-layer switch trunk.
interface GigabitEthernet1/0/24
switchport trunk allowed vlan add 99
Procedure 9
Configure EIGRP (LAN side)
If you are using a dual-router design, complete this procedure.
You must configure a routing protocol between the two routers. This ensures that the HSRP active router has full
reachability information for all WAN remote sites.
Step 1: Enable EIGRP-100 facing the access layer.
In this design, all LAN-facing interfaces and the loopback must be EIGRP interfaces. All interfaces except the
transit-network subinterface should remain passive. The network range must include all interface IP addresses
either in a single network statement or in multiple network statements. This design uses a best practice of
assigning the router ID to a loopback address. Do not include the WAN interface (MPLS PE-CE link interface) as
an EIGRP interface.
router eigrp 100
network [network] [inverse mask]
passive-interface default
no passive-interface [Transit interface]
eigrp router-id [IP address of Loopback0]
no auto-summary
Step 2: Redistribute BGP into EIGRP-100.
A default metric redistributes the BGP routes into EIGRP. By default, only the WAN bandwidth and delay values
are used for metric calculation.
router eigrp 100
default-metric [WAN bandwidth] [WAN delay] 255 1 1500
redistribute bgp 65511
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Tech Tip
Command Reference:
default-metric bandwidth delay reliability loading mtu
bandwidth—Minimum bandwidth of the route in kilobytes per second
delay—Route delay in tens of microseconds.
Example
router eigrp 100
default-metric 100000 100 255 1 1500
network 10.4.0.0 0.1.255.255
network 10.255.0.0 0.0.255.255
redistribute bgp 65511
passive-interface default
no passive-interface GigabitEthernet0/2.99
eigrp router-id 10.255.251.206
no auto-summary
Procedure 10
Configure BGP
If you are using a dual-router design, complete this procedure.
Step 1: On both remote-site MPLS CE routers, configure iBGP and enable the next-hop-self configuration
option.
The dual-carrier MPLS design requires that a BGP link is configured between the CE routers. Because the CE
routers are using the same ASN, this configuration is considered an internal BGP (iBGP) connection. This design
uses iBGP peering using the transit network, which requires the next-hop-self-configuration option.
You must complete this step on both remote-site MPLS CE routers. Note, the iBGP session will not be
established until you complete the transit network and EIGRP (LAN-side) steps.
router bgp 65511
neighbor [iBGP neighbor Transit Net IP] remote-as 65511
neighbor [iBGP neighbor Transit Net IP] next-hop-self
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Step 2: Configure BGP to prevent the remote site from becoming a transit AS.
By default, BGP readvertises all BGP-learned routes. In the dual-MPLS design, this means that MPLS-A routes
will be advertised to MPLS-B and vice-versa. In certain cases, when a link to a MPLS hub has failed, remote
sites will advertise themselves as a transit autonomous system, providing access between the two carriers.
Unless the remote site has been specifically designed for this type of routing behavior, with a high bandwidth
connection, it is a best practice to disable the site from becoming a transit site. You must use a route-map and
an as-path access-list filter. You need to apply this route-map on both remote-site MPLS CE routers. Each router
will apply this outbound to the neighbor for its respective MPLS carrier.
router bgp 65511
neighbor [IP address of PE] route-map NO-TRANSIT-AS out
ip as-path access-list 10 permit ^$
!
route-map NO-TRANSIT-AS permit 10
match as-path 10
Tech Tip
The regular expression ^$ corresponds to routes originated from the remote-site. This
type of filter allows for only the locally originated routes to be advertised.
Step 3: Tune BGP routing to prefer the primary MPLS carrier.
BGP uses a well-known rule set in order to determine the “best path” when the same IP route prefix is reachable
via two different paths. The MPLS dual-carrier design in many cases provides two equal cost paths, and it
is likely that the first path selected will remain the active path unless the routing protocol detects a failure.
Accomplishing the design goal of deterministic routing and primary/secondary routing behavior necessitates
tuning BGP. This requires the use of a route-map and an as-path access-list filter.
router bgp 65511
neighbor [IP address of PE] route-map PREFER-MPLS-A in
Step 4: Apply a route-map inbound to the neighbor for the primary MPLS carrier only.
ip as-path access-list 1 permit _65401$
!
route-map PREFER-MPLS-A permit 10
match as-path 1
set local-preference 200
!
route-map PREFER-MPLS-A permit 20
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Tech Tip
The regular expression _65401$ corresponds to routes originated from the AS 65401
(MPLS-A). This allows BGP to selectively modify the routing information for routes
originated from this AS. In this example, the BGP local preference is 200 for the
primary MPLS carrier. Routes originated from the secondary MPLS carrier continue to
use their default local preference of 100.
Step 5: Add a loopback network for the secondary router.
router bgp 65511
network [Secondary router loopback network] mask 255.255.255.255
Procedure 11
Enable Enhanced Object Tracking
If you are using a dual-router design, complete this procedure.
The HSRP active router remains the active router unless the router is reloaded or fails. Having the HSRP router
remain as the active router can lead to undesired behavior. If the primary MPLS VPN transport were to fail, the
HSRP active router would learn an alternate path through the transit network to the HSRP standby router and
begin to forward traffic across the alternate path. This is sub-optimal routing, and you can address it by using
EOT.
The HSRP active router (primary MPLS CE) can use the IP SLA feature to send echo probes to its MPLS PE
router, and if the PE router becomes unreachable, then the router can lower its HSRP priority, so that the HSRP
standby router can preempt and become the HSRP active router.
This procedure is valid only on the router connected to the primary transport (MPLS VPN).
Step 1: Enable the IP SLA probe, and then send standard ICMP echo (ping) probes at 15-second intervals.
Responses must be received before the timeout of 1000 ms expires. If you are using the MPLS PE router as the
probe destination, the destination address is the same as the BGP neighbor address configured in Procedure 3.
ip sla 100
icmp-echo [probe destination IP address] source-interface [WAN interface]
threshold 1000
timeout 1000
frequency 15
ip sla schedule 100 life forever start-time now
Step 2: Configure EOT based on the IP SLA probe. The object being tracked is the reachability success or
failure of the probe. If the probe is successful, the tracked object status is Up; if it fails, the tracked object status
is Down.
track 50 ip sla 100 reachability
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Step 3: Link HSRP with the tracked object.
All data or voice subinterfaces should enable HSRP tracking.
HSRP can monitor the tracked object status. If the status is down, the HSRP priority is decremented by the
configured priority. If the decrease is large enough, the HSRP standby router preempts.
interface [interface type] [number].[sub-interface number]
standby 1 track 50 decrement 10
Example
PROCESS
interface GigabitEthernet 0/2.64
standby 1 track 50 decrement 10
interface GigabitEthernet 0/2.69
standby 1 track 50 decrement 10
!
track 50 ip sla 100 reachability
!
ip sla 100
icmp-echo 192.168.3.10 source-interface GigabitEthernet0/0
timeout 1000
threshold 1000
frequency 15
ip sla schedule 100 life forever start-time now
Adding a Secondary MPLS Link on an Existing MPLS CE
Router
1. Connect to MPLS PE router
2. Configure BGP for dual-link design
This process includes the additional steps necessary to complete the configuration of an MPLS CE router for an
MPLS WAN dual-carrier remote site (single-router, dual-link).
The following procedures assume that the configuration of an MPLS CE router for an MPLS WAN remote site
(single-router, single-link) has already been completed and BGP dynamic routing has been configured. Only the
additional procedures to add an additional MPLS link to the running MPLS CE router are included here.
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The following figure provides details on how to add a second MPLS backup link on an existing remote-site MPLS
CE router.
Figure 15 - Flowchart for adding an MPLS backup configuration
MPLS CE Router
Configuration Complete
Adding Second
MPLS Link on
Existing MPLS CE
Router Configuration
Procedures
YES
Add MPLS
Secondary
Link?
1. Connect to MPLS PE Router
uter
2. Configure BGP for Dual-link
link
Site Complete
Procedure 1
2130
NO
Connect to MPLS PE router
This procedure applies to the interface used to connect the secondary or additional MPLS carrier.
Step 1: Assign an interface bandwidth value that corresponds to the actual interface speed.
If you are using a subrate service, use the policed rate from the carrier.
The example shows a Gigabit interface (1000 Mbps) with a subrate of 10 Mbps.
interface [interface type] [number]
bandwidth [bandwidth (kbps)]
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Tech Tip
Command Reference:
bandwidth kbps
10 Mbps = 10,000 kbps
Step 2: Assign the IP address and netmask of the WAN interface.
The IP addressing used between CE and PE routers must be negotiated with your MPLS carrier. Typically, a
point-to-point netmask of 255.255.255.252 is used.
interface [interface type] [number]
ip address [IP address] [netmask]
Step 3: Administratively enable the interface and disable Cisco Discovery Protocol.
It is not recommended that you use the Cisco Discovery Protocol on external interfaces.
interface [interface type] [number]
no cdp enable
no shutdown
Example
interface GigabitEthernet0/1
bandwidth 10000
ip address 192.168.4.13 255.255.255.252
ip pim sparse-mode
no cdp enable
no shutdown
Procedure 2
Configure BGP for dual-link design
Step 1: Configure eBGP to add an additional eBGP neighbor and advertise the PE-CE link.
BGP must be configured with the MPLS carrier PE device. The MPLS carrier must provide their ASN (the ASN in
this step is the ASN identifying your site). Because the carrier PE router uses a different ASN, this configuration is
considered an external BGP (eBGP) connection.
It is desirable to advertise a route for the PE-CE link, so you should include this network in a network statement.
You can use it to determine router reachability, for troubleshooting.
The remote-site LAN networks are already advertised based on the configuration already completed in the
“Configuring the Remote-Site MPLS CE Router” process.
router bgp 65511
network [PE-CE link 2 network] mask [PE-CE link 2 netmask]
neighbor [IP address of PE 2] remote-as [carrier ASN]
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Step 2: Configure BGP to prevent the remote site from becoming a transit AS.
By default, BGP readvertises all BGP-learned routes. In the dual-MPLS design, this means that MPLS-A routes
are advertised to MPLS-B and vice-versa. In certain cases, when a link to a MPLS hub has failed, remote sites
will advertise themselves as a transit autonomous system, providing access between the two carriers. Unless the
remote site has been specifically designed for this type of routing behavior, with a high bandwidth connection, it
is a best practice to disable the site from becoming a transit site. To do this, you need to use a route-map and an
as-path access-list filter. Apply this route-map outbound to the neighbors for both MPLS carriers.
router bgp 65511
neighbor [IP address of PE] route-map NO-TRANSIT-AS out
neighbor [IP address of PE 2] route-map NO-TRANSIT-AS out
ip as-path access-list 10 permit ^$
!
route-map NO-TRANSIT-AS permit 10
match as-path 10
Tech Tip
The regular expression ^$ corresponds to routes originated from the remote-site. This
type of filter allows for only the locally originated routes to be advertised.
Step 3: Tune BGP routing to prefer the primary MPLS carrier.
BGP uses a well-known rule set in order to determine the “best path” when the same IP route prefix is reachable
via two different paths. The MPLS dual-carrier design in many cases provides two equal cost paths, and it
is likely that the first path selected will remain the active path unless the routing protocol detects a failure.
Accomplishing the design goal of deterministic routing and primary/secondary routing behavior necessitates
tuning BGP. This requires the use of a route-map and an as-path access-list filter.
router bgp 65511
neighbor [IP address of PE] route-map PREFER-MPLS-A in
Step 4: Apply a route map inbound to the neighbor for the primary MPLS carrier only.
ip as-path access-list 1 permit _65401$
!
route-map PREFER-MPLS-A permit 10
match as-path 1
set local-preference 200
!
route-map PREFER-MPLS-A permit 20
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Tech Tip
The regular expression _65401$ corresponds to routes originated from the AS 65401
(MPLS-A). This allows BGP to selectively modify the routing information for routes
originated from this AS. In this example, the BGP local preference is 200 for the
primary MPLS carrier. Routes originated from the secondary MPLS carrier continue to
use their default local preference of 100. Apply this route-map inbound to the neighbor
for the primary MPLS carrier only.
Example
router bgp 65511
network 192.168.4.12 mask 255.255.255.252
neighbor 192.168.3.14 route-map PREFER-MPLS-A in
neighbor 192.168.3.14 route-map NO-TRANSIT-AS out
neighbor 192.168.4.14 remote-as 65402
neighbor 192.168.4.14 route-map NO-TRANSIT-AS out
!
ip as-path access-list 1 permit _65401$
ip as-path access-list 10 permit ^$
!
route-map NO-TRANSIT-AS permit 10
match as-path 10
!
route-map PREFER-MPLS-A permit 10
match as-path 1
set local-preference 200
!
route-map PREFER-MPLS-A permit 20
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Configuring the Secondary Remote-Site Router
PROCESS
1. Configure the WAN remote router
2. Connect to the MPLS PE router
3. Configure WAN routing
4. Connect router to access-layer switch
5. Configure access-layer routing
6. Configure access-layer HSRP
7. Configure the transit network
8. Configure EIGRP (LAN Side)
If you are using a dual-router, dual-link design, complete this procedure in order to configure the secondary
router in the MPLS WAN remote site.
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The following flowchart provides details about how to configure a secondary remote-site MPLS CE router.
Figure 16 - Remote-site MPLS CE router 2 configuration flowchart
Remote-Site MPLS CE Router
Dual Router, Dual Link (2nd Router)
Remote-Site Router
(Dual Router - Router 2)
Configuration
Procedures
1. Configure the WAN Remote Router
2. Connect to MPLS PE Router
3. Configure WAN Routing
NO
O
Distribution
Layer
Design?
YES
Y
Remote-Site
Router to
Distribution Layer
(Router 2)
ccess Layer Switch
4. Connect Router to Access
1
t to Distribution Layer
1. C
Connectt R
Router
5. Configure Access Layer Routing
2. Configure EIGRP (LAN Side)
6. Configure Access Layer HSRP
7. Configure Transit Network
Site Complete
Procedure 1
Site Complete
2131
8
gu e EIGRP
G
((LAN Side)
S de)
8. Co
Configure
Configure the WAN remote router
Within this design, there are features and services that are common across all WAN remote-site routers. These
are system settings that simplify and secure the management of the solution.
Step 1: Configure the device host name. This makes it easy to identify the device.
hostname [hostname]
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Step 2: Configure local login and password.
The local login account and password provides basic access authentication to a router, and this access provides
only limited operational privileges. The enable password secures access to the device configuration mode. By
enabling password encryption, you prevent the disclosure of plain text passwords when viewing configuration
files.
username admin password c1sco123
enable secret c1sco123
service password-encryption
aaa new-model
By default, HTTPS access to the router uses the enable password for authentication.
Step 3: (Optional) Configure centralized user authentication.
As networks scale in the number of devices to maintain it poses an operational burden to maintain local user
accounts on every device. A centralized authentication, authorization, and accounting (AAA) service reduces
operational tasks per device and provides an audit log of user access for security compliance and root cause
analysis. When AAA is enabled for access control, all management access to the network infrastructure devices
(SSH and HTTPS) is controlled by AAA.
TACACS+ is the primary protocol used to authenticate management logins on the infrastructure devices to
the AAA server. A local AAA user database is also defined in Step 2 on each network infrastructure device to
provide a fallback authentication source in case the centralized TACACS+ server is unavailable.
tacacs server TACACS-SERVER-1
address ipv4 10.4.48.15
key SecretKey
!
aaa group server tacacs+ TACACS-SERVERS
server name TACACS-SERVER-1
!
aaa authentication login default group TACACS-SERVERS local
aaa authorization exec default group TACACS-SERVERS local
aaa authorization console
ip http authentication aaa
Step 4: Configure device management protocols.
Secure HTTP (HTTPS) and Secure Shell (SSH) are secure replacements for the HTTP and Telnet protocols. They
use Secure Sockets Layer (SSL) and Transport Layer Security (TLS) to provide device authentication and data
encryption.
Secure management of the network device is enabled through the use of the SSH and HTTPS protocols. Both
protocols are encrypted for privacy, and the unsecure protocols, Telnet and HTTP, are turned off.
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Specify the transport preferred none on vty lines to prevent errant connection attempts from the CLI prompt.
Without this command, if the ip name-server is unreachable, long timeout delays may occur for mistyped
commands.
ip domain-name cisco.local
ip ssh version 2
no ip http server
ip http secure-server
line vty 0 15
transport input ssh
transport preferred none
Step 5: Enable synchronous logging.
When synchronous logging of unsolicited messages and debug output is turned on, console log messages
are displayed on the console after interactive CLI output is displayed or printed. With this command, you can
continue typing at the device console when debugging is enabled.
line con 0
logging synchronous
Step 6: Enable Simple Network Management Protocol (SNMP). This allows the network infrastructure devices
to be managed by a Network Management System (NMS). SNMPv2c is configured both for a read-only and a
read-write community string.
snmp-server community cisco RO
snmp-server community cisco123 RW
Step 7: If operational support is centralized in your network, you can increase network security by using an
access list to limit the networks that can access your device. In this example, only devices on the 10.4.48.0/24
network will be able to access the device via SSH or SNMP.
access-list 55 permit 10.4.48.0 0.0.0.255
line vty 0 15
access-class 55 in
!
snmp-server community cisco RO 55
snmp-server community cisco123 RW 55
Tech Tip
If you configure an access-list on the vty interface you may lose the ability to use ssh
to login from one router to the next for hop-by-hop troubleshooting.
Step 8: Configure a synchronized clock.
The Network Time Protocol (NTP) is designed to synchronize a network of devices. An NTP network usually gets
its time from an authoritative time source, such as a radio clock or an atomic clock attached to a time server.
NTP then distributes this time across the organizations network.
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You should program network devices to synchronize to a local NTP server in the network. The local NTP server
typically references a more accurate clock feed from an outside source. By configuring console messages, logs,
and debug output to provide time stamps on output, you can cross-reference events in a network.
ntp server 10.4.48.17
ntp update-calendar
!
clock timezone PST -8
clock summer-time PDT recurring
!
service timestamps debug datetime msec localtime
service timestamps log datetime msec localtime
Step 9: Configure an in-band management interface.
The loopback interface is a logical interface that is always reachable as long as the device is powered on and
any IP interface is reachable to the network. Because of this capability, the loopback address is the best way to
manage the switch in-band. Layer 3 process and features are also bound to the loopback interface to ensure
process resiliency.
The loopback address is commonly a host address with a 32-bit address mask. Allocate the loopback address
from a unique network range that is not part of any other internal network summary range.
interface Loopback 0
ip address [ip address] 255.255.255.255
ip pim sparse-mode
Bind the device processes for SNMP, SSH, PIM, TACACS+ and NTP to the loopback interface address for
optimal resiliency.
snmp-server trap-source Loopback0
ip ssh source-interface Loopback0
ip pim register-source Loopback0
ip tacacs source-interface Loopback0
ntp source Loopback0
Step 10: Configure IP Multicast routing.
IP Multicast allows a single IP data stream to be replicated by the infrastructure (routers and switches) and sent
from a single source to multiple receivers. Using IP Multicast is much more efficient than multiple individual
unicast streams or a Broadcast stream that would propagate everywhere. IP Telephony MOH and IP Video
Broadcast Streaming are two examples of IP Multicast applications.
To receive a particular IP Multicast data stream, end hosts must join a multicast group by sending an IGMP
message to their local multicast router. In a traditional IP Multicast design, the local router consults another router
in the network that is acting as an RP to map the receivers to active sources so they can join their streams.
In this design, which is based on sparse mode multicast operation, Auto RP is used to provide a simple yet
scalable way to provide a highly resilient RP environment.
Enable IP Multicast routing on the platforms in the global configuration mode.
ip multicast-routing
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Step 11: Configure every Layer 3 switch and router to discover the IP Multicast RP with autorp. Use the ip pim
autorp listener command to allow for discovery across sparse mode links. This configuration provides for future
scaling and control of the IP Multicast environment and can change based on network needs and design.
ip pim autorp listener
Step 12: Enable sparse mode multicast operation for all Layer 3 interfaces in the network.
ip pim sparse-mode
Procedure 2
Connect to the MPLS PE router
Step 1: Assign an interface bandwidth value that corresponds to the actual interface speed.
If you are using a subrate service, use the policed rate from the carrier.
The example shows a Gigabit interface (1000 Mbps) with a subrate of 10 Mbps.
interface [interface type] [number]
bandwidth [bandwidth (kbps)]
Tech Tip
Command Reference:
bandwidth kbps
10 Mbps = 10,000 kbps
Step 2: Assign the IP address and netmask of the WAN interface.
You must negotiate the IP addressing used between CE and PE routers with your MPLS carrier. Typically, a pointto-point netmask of 255.255.255.252 is used.
interface [interface type] [number]
ip address [IP address] [netmask]
Step 3: Administratively enable the interface and disable Cisco Discovery Protocol.
It is not recommend that you use Cisco Discovery Protocol on external interfaces.
interface [interface type] [number]
no cdp enable
no shutdown
Example
interface GigabitEthernet0/0
bandwidth 25000
ip address 192.168.4.9 255.255.255.252
no cdp enable
no shutdown
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Procedure 3
Configure WAN routing
Step 1: Enable BGP.
To complete this step, you must use a BGP ASN. You might be able to reuse the same value used on the MPLS
VPN CE from the WAN-aggregation site. Consult with your MPLS carrier on the requirements for the ASN.
The CE router advertises only network routes to the PE via BGP in the following cases:
• The route is specified in network statements and is present in the local routing table.
• The route is redistributed into BGP (not applicable in the remote-site use case).
router bgp 65511
no synchronization
bgp router-id [IP address of Loopback0]
bgp log-neighbor-changes
no auto-summary
Step 2: Configure eBGP.
You must configure BGP with the MPLS carrier PE device. The MPLS carrier must provide their ASN (the ASN
in the previous step is the ASN identifying your site). Because the carrier PE router uses a different ASN, this
configuration is considered an external BGP (eBGP) connection.
It is desirable to advertise a route for the PE-CE link, so you should include this network in a network statement.
You can use this to determine router reachability, for troubleshooting.
The remote-site LAN networks must be advertised. The IP assignment for the remote sites was designed so that
all of the networks in use can be summarized within a single aggregate route. The aggregate address configured
below suppresses the more specific routes. If any LAN network is present in the route table, the aggregate
is advertised to the MPLS PE, which offers a measure of resiliency. If the various LAN networks cannot be
summarized, you must list each individually.
The remote-site routers have in-band management configured via the loopback interface. To ensure reachability
of the loopback interfaces in a dual-router design, you must list the loopbacks of both the primary and secondary
routers as BGP networks.
Tech Tip
On the primary MPLS CE router, you must add a network statement for the loopback
address of the secondary MPLS CE router. This is required for loopback resiliency.
router bgp 65511
network [PE-CE link network] mask [PE-CE link netmask]
network [Primary router loopback network] mask 255.255.255.255
network [Secondary router loopback network] mask 255.255.255.255
network [DATA network] mask [netmask]
network [VOICE network] mask [netmask]
aggregate-address [summary IP address] [summary netmask] summary-only
neighbor [IP address of PE] remote-as [carrier ASN]
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Step 3: Configure iBGP between the remote-site MPLS CE routers.
The dual-carrier MPLS design requires that a BGP link is configured between the CE routers. Because the CE
routers are using the same ASN, this configuration is considered an internal BGP (iBGP) connection.
Note, the iBGP session will not be established until you complete the transit network and EIGRP (LAN side) steps.
router bgp 65511
neighbor [iBGP neighbor Transit Net IP] remote-as 65511
neighbor [iBGP neighbor Transit Net IP] next-hop-self
Step 4: Configure BGP to prevent the remote site from becoming a transit AS.
By default, BGP readvertises all BGP learned routes. In the dual-MPLS design, this means that MPLS-A routes
will be advertised to MPLS-B and vice-versa. In certain cases, when a link to an MPLS hub has failed, remote
sites will advertise themselves as a transit autonomous system, providing access between the two carriers.
Unless the remote site has been specifically designed for this type of routing behavior, with a high bandwidth
connection, it is a best practice to disable the site from becoming a transit site. You must use a route-map and
an as-path access-list filter. You need to apply this route map on both remote-site MPLS CE routers. Each router
applies this route map outbound to the neighbor for its respective MPLS carrier.
router bgp 65511
neighbor [IP address of PE 2] route-map NO-TRANSIT-AS out
ip as-path access-list 10 permit ^$
!
route-map NO-TRANSIT-AS permit 10
match as-path 10
Tech Tip
The regular expression ^$ corresponds to routes originated from the remote-site. This
type of filter allows for only the locally originated routes to be advertised.
Example: MPLS CE Router (secondary)
router bgp 65511
no synchronization
bgp router-id 10.255.252.206
bgp log-neighbor-changes
network 192.168.4.8 mask 255.255.255.252
network 10.255.251.206 mask 255.255.255.255
network 10.255.252.206 mask 255.255.255.255
network 10.5.12.0 mask 255.255.255.0
network 10.5.13.0 mask 255.255.255.0
aggregate-address 10.5.8.0 255.255.248.0 summary-only
neighbor 10.5.8.1 remote-as 65511
neighbor 10.5.8.1 next-hop-self
neighbor 192.168.4.10 remote-as 65402
neighbor 192.168.4.10 route-map NO-TRANSIT-AS out
no auto-summary
!
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ip as-path access-list 10 permit ^$
!
route-map NO-TRANSIT-AS permit 10
match as-path 10
Procedure 4
Connect router to access-layer switch
Reader Tip
This guide includes only the additional steps to complete the distribution-layer
configuration. For complete access-layer configuration details, see the Campus Wired
LAN Technology Design Guide.
If you are using a remote-site distribution layer, then skip to the “Deploying a WAN Remote-Site Distribution
Layer” chapter of this guide.
Layer 2 EtherChannels are used to interconnect the CE router to the access layer in the most resilient method
possible. If the access-layer device is a single, fixed-configuration switch, a simple Layer 2 trunk between the
router and switch is used.
In the access-layer design, the remote sites use collapsed routing, with 802.1Q trunk interfaces to the LAN
access layer. The VLAN numbering is locally significant only.
Option 1: Layer 2 EtherChannel from router to access-layer switch
Step 1: Configure a port-channel interface on the router.
interface Port-channel2
description EtherChannel link to RS206-A2960S
no shutdown
Step 2: Configure EtherChannel member interfaces on the router.
Configure the physical interfaces to tie to the logical port-channel by using the channel-group command. The
number for the port-channel and channel-group must match. Not all router platforms can support LACP to
negotiate with the switch, so you configure EtherChannel statically.
interface GigabitEthernet0/1
description RS206-A2960S Gig1/0/23
!
interface GigabitEthernet0/2
description RS206-A2960S Gig2/0/23
!
interface range GigabitEthernet0/1, GigabitEthernet0/2
no ip address
channel-group 2
no shutdown
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Step 3: Configure EtherChannel member interfaces on the access-layer switch
Connect the router EtherChannel uplinks to separate switches in the access layer switch stack, or in the case of
the Cisco Catalyst 4507R+E distribution layer, to separate redundant modules for additional resiliency.
The physical interfaces that are members of a Layer 2 EtherChannel are configured prior to configuring the
logical port-channel interface. Doing the configuration in this order allows for minimal configuration and reduces
errors because most of the commands entered to a port-channel interface are copied to its members’ interfaces
and do not require manual replication.
Configure two or more physical interfaces to be members of the EtherChannel. It is recommended that they
are added in multiples of two. Also, apply the egress QoS macro that was defined in the platform configuration
procedure in order to ensure traffic is prioritized appropriately.
Not all connected router platforms can support LACP to negotiate with the switch, so you configure EtherChannel
statically.
interface GigabitEthernet1/0/23
description Link to RS206-3925-2 Gig0/1
interface GigabitEthernet2/0/23
description Link to RS206-3925-2 Gig0/2
!
interface range GigabitEthernet1/0/23, GigabitEthernet2/0/23
switchport
macro apply EgressQoS
channel-group 2 mode on
logging event link-status
logging event trunk-status
logging event bundle-status
Step 4: Configure EtherChannel trunk on the access-layer switch.
Use an 802.1Q trunk for the connections. This allows the router to provide the Layer 3 services to all the VLANs
defined on the access-layer switch. Prune the VLANs allowed on the trunk to only the VLANs that are active on
the access-layer switch. When using EtherChannel, the interface type is port-channel, and the number must
match the channel group configured in Step 2. Set DHCP Snooping and Address Resolution Protocol (ARP)
inspection to trust.
interface Port-channel2
description EtherChannel link to RS206-3925-2
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 64,69,99
switchport mode trunk
ip arp inspection trust
spanning-tree portfast trunk
ip dhcp snooping trust
no shutdown
The Cisco Catalyst 2960-S Series and 4500 Series switches do not require the switchport trunk encapsulation
dot1q command.
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Option 2: Layer 2 trunk from router to access-layer switch
Step 1: Enable the physical interface on the router.
interface GigabitEthernet0/2
description RS206-A2960S Gig1/0/23
no ip address
no shutdown
Step 2: Configure the trunk on the access-layer switch.
Use an 802.1Q trunk for the connection. This allows the router to provide the Layer 3 services to all the VLANs
defined on the access-layer switch. Prune the VLANs allowed on the trunk to only the VLANs that are active on
the access-layer switch, and then set DHCP Snooping and Address Resolution Protocol (ARP) inspection to trust.
interface GigabitEthernet1/0/23
description Link to RS206-3925-2 Gig0/2
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 64,69,99
switchport mode trunk
ip arp inspection trust
spanning-tree portfast trunk
macro apply EgressQoS
logging event link-status
logging event trunk-status
ip dhcp snooping trust
no shutdown
The Cisco Catalyst 2960-S Series and 4500 Series switches do not require the switchport trunk encapsulation
dot1q command.
Procedure 5
Configure access-layer routing
This remote-site MPLS CE router is the second router of a dual-router design, and HSRP is configured at the
access layer. The actual interface IP assignments are configured in the following procedure.
Step 1: Create subinterfaces and assign VLAN tags.
After the physical interface or port-channel has been enabled, you can map the appropriate data or voice
subinterfaces to the VLANs on the LAN switch. The subinterface number does not need to equate to the 802.1Q
tag, but making them the same simplifies the overall configuration.
interface [type][number].[sub-interface number]
encapsulation dot1Q [dot1q VLAN tag]
Step 2: Repeat the subinterface portion of the previous step for all data or voice VLANs.
Step 3: Configure IP settings for each subinterface.
This design uses an IP addressing convention with the default gateway router assigned an IP address and IP
mask combination of N.N.N.1 255.255.255.0 where N.N.N is the IP network and 1 is the IP host.
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When using a centralized DHCP server, routers with LAN interfaces connected to a LAN using DHCP for endstation IP addressing must use an IP helper.
This remote-site MPLS CE router is the second router of a dual-router design and HSRP is configured at the
access layer. The actual interface IP assignments will be configured in the following procedure.
interface [type][number].[sub-interface number]
description [usage]
ip helper-address 10.4.48.10
ip pim sparse-mode
Example: Layer 2 EtherChannel
interface Port-channel2
no ip address
no shutdown
!
hold-queue 150 in
!
interface Port-channel2.64
description Data
encapsulation dot1Q 64
ip helper-address 10.4.48.10
ip pim sparse-mode
!
interface Port-channel2.69
description Voice
encapsulation dot1Q 69
ip helper-address 10.4.48.10
ip pim sparse-mode
Example: Layer 2 Trunk
interface GigabitEthernet0/2
no ip address
no shutdown
!
interface GigabitEthernet0/2.64
description Data
encapsulation dot1Q 64
ip helper-address 10.4.48.10
ip pim sparse-mode
!
interface GigabitEthernet0/2.69
description Voice
encapsulation dot1Q 69
ip helper-address 10.4.48.10
ip pim sparse-mode
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Procedure 6
Configure access-layer HSRP
Configure HSRP to use a virtual IP (VIP) as a default gateway that is shared between two routers. The HSRP
active router is the MPLS CE router connected to the primary MPLS carrier, and the HSRP standby router is the
router connected to the secondary MPLS carrier or backup link.
In this procedure, you configure the HSRP active router with a standby priority that is higher than the HSRP
standby router. The router with the higher standby priority value is elected as the HSRP active router. The
preempt option allows a router with a higher priority to become the HSRP active, without waiting for a scenario
where there is no router in the HSRP active state. The relevant HSRP parameters for the router configuration are
shown in the following table.
Table 12 - WAN remote-site HSRP parameters (dual-router design)
Router
HSRP role
Virtual IP
address (VIP)
Real IP address
HSRP priority
PIM DR priority
MPLS CE (primary)
Active
.1
.2
110
110
MPLS CE (secondary) or
DMVPN Spoke
Standby
.1
.3
105
105
The dual-router access-layer design requires a modification for resilient multicast. The PIM designated router
(DR) should be on the HSRP active router. The DR is normally elected based on the highest IP address, and it has
no awareness of the HSRP configuration. In this design, assigning the HSRP active router a lower real IP address
than the HSRP standby router requires a modification to the PIM configuration. You can influence the PIM DR
election by explicitly setting the DR priority on the LAN-facing subinterfaces for the routers.
Tech Tip
The HSRP priority and PIM DR priority are shown in the previous table to be the same
value; however, you are not required to use identical values.
Step 1: Configure HSRP.
interface [type][number].[sub-interface number]
ip address [LAN network 1 address] [LAN network 1 netmask]
ip pim dr-priority 105
standby version 2
standby 1 ip [LAN network 1 gateway address]
standby 1 priority 105
standby 1 preempt
standby 1 authentication md5 key-string c1sco123
Step 2: Repeat this procedure for all data or voice subinterfaces.
Example: MPLS CE Router (Secondary) with Layer 2 EtherChannel
interface Port-channel2
no ip address
no shutdown
!
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interface Port-channel2.64
description Data
encapsulation dot1Q 64
ip address 10.5.12.3 255.255.255.0
ip helper-address 10.4.48.10
ip pim dr-priority 105
ip pim sparse-mode
standby version 2
standby 1 ip 10.5.12.1
standby 1 priority 105
standby 1 preempt
standby 1 authentication md5 key-string c1sco123
!
interface Port-channel2.69
description Voice
encapsulation dot1Q 69
ip address 10.5.13.3 255.255.255.0
ip helper-address 10.4.48.10
ip pim dr-priority 105
ip pim sparse-mode
standby version 2
standby 1 ip 10.5.13.1
standby 1 priority 105
standby 1 preempt
standby 1 authentication md5 key-string c1sco123
Example: MPLS CE Router (Secondary) with Layer 2 Trunk
interface GigabitEthernet0/2
no ip address
no shutdown
!
interface GigabitEthernet0/2.64
description Data
encapsulation dot1Q 64
ip address 10.5.12.3 255.255.255.0
ip helper-address 10.4.48.10
ip pim dr-priority 105
ip pim sparse-mode
standby version 2
standby 1 ip 10.5.12.1
standby 1 priority 105
standby 1 preempt
standby 1 authentication md5 key-string c1sco123
!
interface GigabitEthernet0/2.69
description Voice
encapsulation dot1Q 69
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ip address 10.5.13.3 255.255.255.0
ip helper-address 10.4.48.10
ip pim dr-priority 105
ip pim sparse-mode
standby version 2
standby 1 ip 10.5.13.1
standby 1 priority 105
standby 1 preempt
standby 1 authentication md5 key-string c1sco123
Procedure 7
Configure the transit network
Configure the transit network between the two routers. You use this network for router-router communication
and to avoid hairpinning. The transit network should use an additional subinterface on the router interface that is
already being used for data or voice.
There are no end stations connected to this network, so HSRP and DHCP are not required.
Step 1: On the secondary MPLS CE router, configure the transit network interface.
interface [interface type][number].[sub-interface number]
encapsulation dot1Q [dot1q VLAN tag]
ip address [transit net address] [transit net netmask]
ip pim sparse-mode
Example
interface GigabitEthernet0/2.99
description Transit Net
encapsulation dot1Q 99
ip address 10.5.8.2 255.255.255.252
ip pim sparse-mode
Procedure 8
Configure EIGRP (LAN Side)
You must configure a routing protocol between the two routers. This ensures that the HSRP active router has full
reachability information for all WAN remote sites.
Step 1: Enable EIGRP-100 facing the access layer.
In this design, all LAN-facing interfaces and the loopback must be EIGRP interfaces. All interfaces except the
transit-network subinterface should remain passive. The network range must include all interface IP addresses
either in a single network statement or in multiple network statements. This design uses a best practice of
assigning the router ID to a loopback address. Do not include the WAN interface (MPLS PE-CE link interface) as
an EIGRP interface.
router eigrp 100
network [network] [inverse mask]
passive-interface default
no passive-interface [Transit interface]
eigrp router-id [IP address of Loopback0]
no auto-summary
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Step 2: Redistribute BGP into EIGRP-100.
A default metric redistributes the BGP routes into EIGRP. By default, only the WAN bandwidth and delay values
are used for metric calculation.
router eigrp 100
default-metric [WAN bandwidth] [WAN delay] 255 1 1500
redistribute bgp 65511
Tech Tip
Command Reference:
default-metric bandwidth delay reliability loading mtu
bandwidth—Minimum bandwidth of the route in kilobytes per second
delay—Route delay in tens of microseconds.
Example
router eigrp 100
default-metric 100000 100 255 1 1500
network 10.4.0.0 0.1.255.255
redistribute bgp 65511
passive-interface default
no passive-interface GigabitEthernet0/2.99
eigrp router-id 10.255.252.206
no auto-summary
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Deploying a WAN Remote-Site
Distribution Layer
PROCESS
Deployment Details
Connecting the Single or Primary Remote-Site Router to the
Distribution Layer
1. Connect router to distribution layer
2. Configure EIGRP (LAN side)
3. Configure the transit network
4. Configure BGP
If you are configuring an MPLS WAN remote-site that uses a single-router, single link design or a dual-router,
dual-link design, complete this process. This process includes all required procedures in order to connect either
the single-router in a single-link design or the primary router in a dual-link design to a LAN distribution layer.
Both distribution-layer remote-site options are shown in the following figure.
Figure 17 - WAN remote site—Connection to distribution layer
WAN
WAN
R1
802.1Q Trunk
(50)
802.1Q Trunk (xx-xx)
R2
802.1Q Trunk
(50, 99)
802.1Q Trunk (64, 69)
VLAN 50 - Router 1 Link
Deploying a WAN Remote-Site Distribution Layer
802.1Q Trunk
(54, 99)
802.1Q Trunk (xx-xx)
VLAN 50 - Router 1 Link
VLAN 54 - Router 2 Link
VLAN 99 - Transit
December 2013
2185
R1
75
Procedure 1
Connect router to distribution layer
Reader Tip
This guide includes only the additional steps to complete the distribution-layer
configuration. For complete distribution-layer configuration details, see the Campus
Wired LAN Technology Design Guide.
Layer 2 EtherChannels are used to interconnect the CE router to the distribution layer in the most resilient
method possible. This connection allows for multiple VLANs to be included on the EtherChannel if necessary.
Step 1: Configure a port-channel interface on the router.
interface Port-channel1
description EtherChannel link to RS200-D3750X
no shutdown
Step 2: Configure the port channel subinterfaces and assign IP addresses.
After you have enabled the interface, map the appropriate subinterfaces to the VLANs on the distributionlayer switch. The subinterface number does not need to equate to the 802.1Q tag, but making them the same
simplifies the overall configuration.
The subinterface configured on the router corresponds to a VLAN interface on the distribution-layer switch.
Traffic is routed between the devices with the VLAN acting as a point-to-point link.
interface Port-channel1.50
description R1 routed link to distribution layer
encapsulation dot1Q 50
ip address 10.5.0.1 255.255.255.252
ip pim sparse-mode
Step 3: On the router, configure EtherChannel member interfaces.
Configure the physical interfaces to tie to the logical port-channel by using the channel-group command. The
number for the port-channel and channel-group must match. Not all router platforms can support LACP to
negotiate with the switch, so you configure EtherChannel statically.
interface GigabitEthernet0/1
description RS200-D3750X Gig1/0/1
!
interface GigabitEthernet0/2
description RS200-D3750X Gig2/0/1
!
interface range GigabitEthernet0/1, GigabitEthernet0/2
no ip address
channel-group 1
no shutdown
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Step 4: On the distribution-layer switch, configure the VLAN.
vlan 50
name R1-link
Step 5: On the distribution-layer switch, configure Layer 3.
Configure a VLAN interface, also known as a switch virtual interface (SVI), for the new VLAN added. The SVI is
used for point-to-point IP routing between the distribution layer and the WAN router.
interface Vlan50
ip address 10.5.0.2 255.255.255.252
ip pim sparse-mode
no shutdown
Step 6: On the distribution-layer switch, configure EtherChannel member interfaces.
Connect the router EtherChannel uplinks to separate switches in the distribution layer.
If you are using a Cisco Catalyst 4507R+E chassis in the distribution layer, connect the uplinks to separate
redundant modules. This provides additional resiliency.
The physical interfaces that are members of a Layer 2 EtherChannel are configured prior to configuring the
logical port-channel interface. Doing the configuration in this order allows for minimal configuration and reduces
errors because most of the commands entered to a port-channel interface are copied to its member interfaces
and do not require manual replication.
Configure two or more physical interfaces to be members of the EtherChannel. It is recommended that they
are added in multiples of two. Also, apply the egress QoS macro that was defined in the platform configuration
procedure to ensure traffic is prioritized appropriately.
Not all connected router platforms can support LACP to negotiate with the switch, so you configure EtherChannel
statically.
interface GigabitEthernet1/0/1
description Link to RS200-3925-1 Gig0/1
interface GigabitEthernet2/0/1
description Link to RS200-3925-1 Gig0/2
!
interface range GigabitEthernet1/0/1, GigabitEthernet2/0/1
switchport
macro apply EgressQoS
channel-group 1 mode on
logging event link-status
logging event trunk-status
logging event bundle-status
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Step 7: On the distribution-layer switch, configure an EtherChannel trunk.
Use an 802.1Q trunk for the connection. This allows the router to provide the Layer 3 services to all the VLANs
defined on the distribution-layer switch. Prune the VLANs allowed on the trunk to only the VLANs that are active
on the distribution-layer switch. When using EtherChannel, the interface type is port-channel, and the number
must match the channel group configured in Step 3. .
interface Port-channel1
description EtherChannel link to RS200-3925-1
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 50
switchport mode trunk
spanning-tree portfast trunk
no shutdown
Cisco Catalyst 4500 Series switches do not require the switchport trunk encapsulation dot1q command.
Procedure 2
Configure EIGRP (LAN side)
You must configure a routing protocol between the router and distribution layer.
Step 1: On the router, enable EIGRP-100 facing the distribution layer.
In this design, all distribution-layer-facing subinterfaces and the loopback must be EIGRP interfaces. All other
interfaces should remain passive. The network range must include all interface IP addresses either in a single
network statement or in multiple network statements. This design uses a best practice of assigning the router ID
to a loopback address.
router eigrp 100
network 10.5.0.0 0.0.255.255
network 10.255.0.0 0.0.255.255
passive-interface default
no passive-interface [interface]
eigrp router-id [IP address of Loopback0]
no auto-summary
Step 2: On the router, redistribute BGP into EIGRP-100.
A default metric redistributes the BGP routes into EIGRP. By default, only the WAN bandwidth and delay values
are used for metric calculation.
router eigrp [as number]
default-metric [WAN bandwidth (Kbps)] [WAN delay (usec)] 255 1 1500
redistribute bgp 65511
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Example
router eigrp 100
default-metric 100000 100 255 1 1500
network 10.5.0.0 0.0.255.255
network 10.255.0.0 0.0.255.255
passive-interface default
no passive-interface Port-channel1.50
eigrp router-id 10.255.251.200
no auto-summary
Step 3: On the distribution-layer switch VLAN interface, enable EIGRP.
EIGRP is already configured on the distribution-layer switch. The VLAN interface that connects to the router must
be configured as a non-passive EIGRP interface.
router eigrp 100
no passive-interface Vlan50
Procedure 3
Configure the transit network
If you are using a dual-router design, complete this procedure.
Configure the transit network between the two routers. You use this network for router-router communication
and to avoid hairpinning. The transit network should use an additional subinterface on the EtherChannel interface
that is already used to connect to the distribution layer.
The transit network must be a non-passive EIGRP interface.
There are no end stations connected to this network, so HSRP and DHCP are not required. The transit network
uses Layer 2 pass-through on the distribution-layer switch, so no SVI is required.
Step 1: On the router, configure the transit net interface.
interface Port-channel1.99
description Transit Net
encapsulation dot1Q 99
ip address 10.5.0.9 255.255.255.252
ip pim sparse-mode
Step 2: On the router, enable EIGRP on the transit network interface.
router eigrp 100
no passive-interface Port-channel1.99
Step 3: On the distribution-layer switch, configure the transit network VLAN.
vlan 99
name Transit-net
Step 4: Add the transit network VLAN to the existing distribution-layer switch EtherChannel trunk.
interface Port-channel1
switchport trunk allowed vlan add 99
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Procedure 4
Configure BGP
If you are using a dual-router design, complete this procedure.
Step 1: Configure iBGP between the remote-site MPLS CE routers.
The dual-carrier MPLS design requires that a BGP link is configured between the CE routers. Because the CE
routers are using the same ASN, this configuration is considered an internal BGP (iBGP) connection. This design
uses iBGP peering using device loopback addresses, which requires the update-source and next-hop-selfconfiguration options.
You must complete this step on both remote-site MPLS CE routers. Note, the iBGP session will not be
established until you complete the transit network and EIGRP (LAN side) steps.
router bgp 65511
neighbor [iBGP neighbor Transit Net IP] remote-as 65511
neighbor [iBGP neighbor Transit Net IP] next-hop-self
Step 2: Configure BGP to prevent the remote site from becoming a transit AS.
By default, BGP readvertises all BGP learned routes. In the dual-MPLS design, this means that MPLS-A routes
are advertised to MPLS-B and vice-versa. In certain cases, when a link to an MPLS hub has failed, remote sites
advertise themselves as a transit autonomous system, providing access between the two carriers. Unless the
remote site has been specifically designed for this type of routing behavior, with a high bandwidth connection,
it is a best practice to disable the site from becoming a transit site. You must use a route-map and an as-path
access-list filter. You need to apply this route-map on both remote-site MPLS CE routers. Each router applies
this outbound to the neighbor for its respective MPLS carrier.
router bgp 65511
neighbor [IP address of PE] route-map NO-TRANSIT-AS out
ip as-path access-list 10 permit ^$
!
route-map NO-TRANSIT-AS permit 10
match as-path 10
Tech Tip
The regular expression ^$ corresponds to routes originated from the remote-site. This
type of filter allows for only the locally originated routes to be advertised.
Step 3: Tune BGP routing to prefer the primary MPLS carrier.
BGP uses a well-known rule set in order to determine the “best path” when the same IP route prefix is reachable
via two different paths. The MPLS dual-carrier design in many cases provides two equal cost paths, and it
is likely that the first path selected will remain the active path unless the routing protocol detects a failure.
Accomplishing the design goal of deterministic routing and primary/secondary routing behavior necessitates
tuning BGP. This requires the use of a route-map and an as-path access-list filter.
router bgp 65511
neighbor [IP address of PE] route-map PREFER-MPLS-A in
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Step 4: Apply a route-map inbound to the neighbor for the primary MPLS carrier only.
ip as-path access-list 1 permit _65401$
!
route-map PREFER-MPLS-A permit 10
match as-path 1
set local-preference 200
!
route-map PREFER-MPLS-A permit 20
Tech Tip
The regular expression _65401$ corresponds to routes originated from the AS 65401
(MPLS-A). This allows BGP to selectively modify the routing information for routes
originated from this AS. In this example, the BGP local preference is 200 for the
primary MPLS carrier. Routes originated from the secondary MPLS carrier continue to
use their default local preference of 100.
Step 5: Add a loopback network for the secondary router.
PROCESS
router bgp 65511
network [Secondary router loopback network] mask 255.255.255.255
Connecting the Secondary Remote-Site Router to the
Distribution Layer
1. Connect router to distribution layer
2. Configure EIGRP (LAN side)
If you are using dual-carrier design for the MPLS WAN remote site, complete this process. This process
connects the distribution layer to the second router of the dual-router, dual-link design. This design uses a
separate routed link from the second router of the dual-router scenario to the LAN distribution-layer switch.
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The dual-router, distribution layer-remote-site design is shown in the following figure.
Figure 18 - WAN remote site—Connection to distribution layer
WAN
R1
VLAN 50 - Router 1 Link
VLAN 54 - Router 2 Link
VLAN 99 - Transit
802.1Q Trunk
(50, 99)
802.1Q Trunk
(54, 99)
802.1Q Trunk
(yy, zz)
2132
802.1Q Trunk
(ww, xx)
R2
Procedure 1
Connect router to distribution layer
Reader Tip
Please refer to the Campus Wired LAN Technology Design Guide for complete
distribution layer configuration details. This guide only includes the additional steps to
complete the distribution layer configuration.
Layer 2 EtherChannels are used to interconnect the CE router to the distribution layer in the most resilient
method possible. This connection allows for multiple VLANs to be included on the EtherChannel if necessary.
Step 1: On the secondary router, configure a port-channel interface.
interface Port-channel2
description EtherChannel link to RS200-D3750X
no shutdown
Step 2: Configure the port channel subinterfaces and assign IP address.
After you have enabled the interface, map the appropriate subinterfaces to the VLANs on the distributionlayer switch. The subinterface number does not need to equate to the 802.1Q tag, but making them the same
simplifies the overall configuration.
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The subinterface configured on the router corresponds to a VLAN interface on the distribution-layer switch.
Traffic is routed between the devices with the VLAN acting as a point-to-point link.
interface Port-channel2.54
description R2 routed link to distribution layer
encapsulation dot1Q 54
ip address 10.5.0.5 255.255.255.252
ip pim sparse-mode
Step 3: On the router, configure the transit network interface.
interface Port-channel2.99
description Transit Net
encapsulation dot1Q 99
ip address 10.5.0.10 255.255.255.252
ip pim sparse-mode
Step 4: On the router, configure the EtherChannel member interfaces.
Configure the physical interfaces to tie to the logical port-channel using by the channel-group command. The
number for the port-channel and channel-group must match. Not all router platforms can support LACP to
negotiate with the switch, so you configure EtherChannel statically.
interface GigabitEthernet0/1
description RS200-D3750X Gig1/0/2
!
interface GigabitEthernet0/2
description RS200-D3750X Gig2/0/2
!
interface range GigabitEthernet0/1, GigabitEthernet0/2
no ip address
channel-group 2
no shutdown
Step 5: On the distribution-layer switch, configure a VLAN.
vlan 54
name R2-link
Step 6: On the distribution-layer switch, configure Layer 3.
Configure a VLAN interface, also known as a switch virtual interface (SVI), for the new VLAN added. The SVI is
used for point-to-point IP routing between the distribution layer and the WAN router.
interface Vlan54
ip address 10.5.0.6 255.255.255.252
ip pim sparse-mode
no shutdown
Step 7: On the distribution-layer switch, configure EtherChannel member interfaces.
Connect the router EtherChannel uplinks to separate switches in the distribution layer switches or stack, and in
the case of the Cisco Catalyst 4507R+E distribution layer, to separate redundant modules for additional resiliency.
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The physical interfaces that are members of a Layer 2 EtherChannel are configured prior to configuring the
logical port-channel interface. Doing the configuration in this order allows for minimal configuration and reduces
errors because most of the commands entered to a port-channel interface are copied to its member interfaces
and do not require manual replication.
Configure two or more physical interfaces to be members of the EtherChannel. It is recommended that they
are added in multiples of two. Also, apply the egress QoS macro that was defined in the platform configuration
procedure to ensure traffic is prioritized appropriately.
Not all connected router platforms can support LACP to negotiate with the switch, so you configure EtherChannel
statically.
interface GigabitEthernet1/0/2
description Link to RS200-3925-2 Gig0/1
interface GigabitEthernet2/0/2
description Link to RS200-3925-2 Gig0/2
!
interface range GigabitEthernet1/0/2, GigabitEthernet2/0/2
switchport
macro apply EgressQoS
channel-group 2 mode on
logging event link-status
logging event trunk-status
logging event bundle-status
Step 8: On the distribution-layer switch, configure an EtherChannel trunk.
Use an 802.1Q trunk for the connection. This allows the router to provide the Layer 3 services to all the VLANs
defined on the distribution-layer switch. Prune the VLANs allowed on the trunk to only the VLANs that are active
on the distribution-layer switch. When using EtherChannel, the interface type is port-channel, and the number
must match the channel group configured in Step 4.
interface Port-channel2
description EtherChannel link to RS200-3925-2
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 54,99
switchport mode trunk
spanning-tree portfast trunk
no shutdown
Cisco Catalyst 4500 Series switches do not require the switchport trunk encapsulation dot1q command.
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Procedure 2
Configure EIGRP (LAN side)
You must configure a routing protocol between the router and distribution layer.
Step 1: On the router, enable EIGRP-100 facing the distribution layer.
In this design, all distribution-layer-facing subinterfaces and the loopback must be EIGRP interfaces. All other
interfaces should remain passive. The network range must include all interface IP addresses either in a single
network statement or in multiple network statements. This design uses a best practice of assigning the router ID
to a loopback address.
router eigrp 100
network 10.5.0.0 0.0.255.255
network 10.255.0.0 0.0.255.255
passive-interface default
no passive-interface [routed link interface]
no passive-interface [transit net interface]
eigrp router-id [IP address of Loopback0]
no auto-summary
Step 2: On the router, redistribute BGP into EIGRP-100.
A default metric redistributes the BGP routes into EIGRP. By default, only the WAN bandwidth and delay values
are used for metric calculation.
router eigrp [as number]
default-metric [WAN bandwidth (Kbps)] [WAN delay (usec)] 255 1 1500
redistribute bgp 65511
Example
router eigrp 100
default-metric 500000 100 255 1 1500
network 10.5.0.0 0.0.255.255
network 10.255.0.0 0.0.255.255
passive-interface default
no passive-interface Port-channel2.54
no passive-interface Port-channel2.99
eigrp router-id 10.255.252.200
no auto-summary
Step 3: On the distribution-layer switch VLAN interface, enable EIGRP.
EIGRP is already configured on the distribution-layer switch. The VLAN interface that connects to the router must
be configured as a non-passive EIGRP interface.
router eigrp 100
no passive-interface Vlan54
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Deploying WAN Quality of Service
When configuring the WAN-edge QoS, you are defining how traffic egresses your network. It is critical that the
classification, marking, and bandwidth allocations align to the service provider offering to ensure consistent QoS
treatment end to end.
Deployment Details
PROCESS
Configuring QoS
1. Create the QoS Maps to Classify Traffic
2. Create the policy map that marks BGP traffic
3. Define a policy map that defines the queuing policy
4. Configure shaping and queuing policy
5. Apply the shaping and queuing policy to a physical interface
Procedure 1
Create the QoS Maps to Classify Traffic
The class-map command defines a traffic class and identifies traffic to associate with the class name. These
class names are used when configuring policy maps that define actions you wish to take against the traffic
type. The class-map command sets the match logic. In this case, the match-any keyword indicates that the
maps match any of the specified criteria. This keyword is followed by the name you want to assign to the class
of service. After you have configured the class-map command, you define specific values, such as DSCP and
protocols, to match with the match command. You use the following two forms of the match command: match
dscp and match protocol.
Use the following steps to configure the required WAN class maps and matching criteria.
Step 1: For each of the six WAN classes of service listed in Table 13, create a class map for DSCP matching.
You do not need to explicitly configure the default class.
class-map match-any [class-map name]
match dscp [dcsp value] [optional additional dscp value(s)]
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Table 13 - QoS classes of service
Class of service
Traffic type
DSCP values
Bandwidth %
Congestion
avoidance
VOICE
Voice traffic
ef
10 (PQ)
—
INTERACTIVE-VIDEO
Interactive video
(such as video conferencing)
cs4, af41
23 (PQ)
—
CRITICAL-DATA
Highly interactive (such as Telnet, Citrix, and
Oracle thin clients)
af31, cs3
15
DSCP-based
DATA
Data
af21
19
DSCP-based
SCAVENGER
Scavenger
af11, cs1
5
—
NETWORK-CRITICAL
Routing protocols; operations, administration
and maintenance (OAM) traffic.
cs6, cs2
3
—
default
Best effort
other
25
random
Step 2: If you are using a WAN-aggregation MPLS CE router or a WAN remote-site MPLS CE router that is using
BGP, create a class map for BGP protocol matching.
BGP traffic is not explicitly tagged with a DSCP value. Use NBAR to match BGP by protocol.
class-map match-any [class-map name]
match ip protocol [protocol name]
Example
class-map match-any VOICE
match dscp ef
!
class-map match-any INTERACTIVE-VIDEO
match dscp cs4 af41
!
class-map match-any CRITICAL-DATA
match dscp af31 cs3
!
class-map match-any DATA
match dscp af21
!
class-map match-any SCAVENGER
match dscp af11 cs1
!
class-map match-any NETWORK-CRITICAL
match dscp cs6 cs2
!
class-map match-any BGP-ROUTING
match protocol bgp
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Tech Tip
You do not need to configure a best-effort class. This is implicitly included within classdefault as shown in Procedure 4.
Procedure 2
Create the policy map that marks BGP traffic
If you are using a WAN-aggregation MPLS CE router or a WAN remote-site MPLS CE router that uses BGP,
complete this procedure.
To ensure proper treatment of BGP routing traffic in the WAN, you must assign a DSCP value of cs6. Although
the class map you created in the previous step matches all BGP traffic to the class named BGP, you must
configure a policy map to assign the required DSCP value to all BGP traffic.
Step 1: Create a policy map, and then assign it a DSCP value of cs6.
policy-map MARK-BGP
class BGP-ROUTING
set dscp cs6
Procedure 3
Define a policy map that defines the queuing policy
This procedure applies to all WAN routers.
The WAN policy map references the class names you created in the previous procedures and defines the
queuing behavior along with the maximum guaranteed bandwidth allocated to each class. This specification is
accomplished with the use of a policy map. Then, each class within the policy map invokes an egress queue,
assigns a percentage of bandwidth, and associates a specific traffic class to that queue. One additional default
class defines the minimum allowed bandwidth available for best-effort traffic.
The local router policy maps define seven classes while most service providers offer only six classes of service.
The NETWORK-CRITICAL policy map is defined in order to ensure the correct classification, marking, and
queuing of network-critical traffic on egress to the WAN. After the traffic has been transmitted to the service
provider, the network-critical traffic is typically remapped by the service provider into the critical data class. Most
providers perform this remapping by matching on DSCP values cs6 and cs2.
Step 1: Create the parent policy map.
policy-map [policy-map-name]
Step 2: Apply the previously created class map.
class [class-name]
Step 3: (Optional) Assign the maximum guaranteed bandwidth for the class.
bandwidth percent [percentage]
Step 4: (Optional) Define the priority queue for the class.
priority percent [percentage]
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Step 5: (Optional) Apply the child service policy.
This is an optional step only for the NETWORK-CRITICAL class of service with the MARK-BGP child service
policy.
service-policy [policy-map-name]
Step 6: (Optional) Define the congestion mechanism.
random-detect [type]
Step 7: Repeat Step 2 through Step 6 for each class in Table 13, including class-default.
Example
policy-map WAN
class VOICE
priority percent 10
class INTERACTIVE-VIDEO
priority percent 23
class CRITICAL-DATA
bandwidth percent 15
random-detect dscp-based
class DATA
bandwidth percent 19
random-detect dscp-based
class SCAVENGER
bandwidth percent 5
class NETWORK-CRITICAL
bandwidth percent 3
service-policy MARK-BGP
class class-default
bandwidth percent 25
Tech Tip
Although these bandwidth assignments represent a good baseline, it is important to
consider your actual traffic requirements per class and adjust the bandwidth settings
accordingly.
random-detect
Procedure 4
Configure shaping and queuing policy
With WAN interfaces using Ethernet as an access technology, the demarcation point between the enterprise
and service provider may no longer have a physical-interface bandwidth constraint. Instead, a specified amount
of access bandwidth is contracted with the service provider. To ensure the offered load to the service provider
does not exceed the contracted rate that results in the carrier discarding traffic, you need to configure shaping
on the physical interface. This shaping is accomplished with a QoS service policy. You configure a QoS service
policy on the outside Ethernet interface, and this parent policy includes a shaper that then references a second
or subordinate (child) policy that enables queuing within the shaped rate. This is called a hierarchical Class-Based
Weighted Fair Queuing (HCBWFQ) configuration. When you configure the shape average command, ensure that
the value matches the contracted bandwidth rate from your service provider.
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This procedure applies to all WAN routers. You can repeat this procedure multiple times to support devices that
have multiple WAN connections attached to different interfaces.
Step 1: Create the parent policy map.
As a best practice, embed the interface name within the name of the parent policy map.
policy-map [policy-map-name]
Step 2: Configure the shaper.
class [class-name]
shape [average | peak] [bandwidth (bps)]
Step 3: Apply the child service policy.
service-policy [policy-map-name]
Example
This example shows a router with a 20-Mbps link on interface GigabitEthernet0/0 and a 10-Mbps link on
interface GigabitEthernet0/1.
policy-map WAN-INTERFACE-G0/0
class class-default
shape average 20000000
service-policy WAN
!
policy-map WAN-INTERFACE-G0/1
class class-default
shape average 10000000
service-policy WAN
Procedure 5
Apply the shaping and queuing policy to a physical interface
To invoke shaping and queuing on a physical interface, you must apply the parent policy that you configured in
the previous procedure.
This procedure applies to all WAN routers. You can repeat this procedure multiple times to support devices that
have multiple WAN connections attached to different interfaces.
Step 1: Select the WAN interface.
interface [interface type] [number]
Step 2: Apply the WAN QoS policy in the outbound direction.
service-policy output [policy-map-name]
Example
interface GigabitEthernet0/0
service-policy output WAN-INTERFACE-G0/0
!
interface GigabitEthernet0/1
service-policy output WAN-INTERFACE-G0/1
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Appendix A: Product List
WAN Remote Site
Functional Area
Product Description
Part Numbers
Software
Modular WAN Remote-site Router
Cisco ISR 4451-X Security Bundle w/SEC license PAK
ISR4451-X-SEC/K9
15.3(3)S
securityk9 license
Cisco 3945 Voice Sec. Bundle, PVDM3-64, UC and
SEC License PAK
C3945-VSEC/K9
Cisco 3925 Voice Sec. Bundle, PVDM3-64, UC and
SEC License PAK
C3925-VSEC/K9
15.2(4)M4
securityk9 license
datak9 license
Data Paper PAK for Cisco 3900 series
SL-39-DATA-K9
Cisco 2951 Voice Sec. Bundle, PVDM3-32, UC and
SEC License PAK
C2951-VSEC/K9
Cisco 2921 Voice Sec. Bundle, PVDM3-32, UC and
SEC License PAK
C2921-VSEC/K9
Cisco 2911 Voice Sec. Bundle, PVDM3-32, UC and
SEC License PAK
C2911-VSEC/K9
Data Paper PAK for Cisco 2900 series
SL-29-DATA-K9
1941 WAAS Express only Bundle
C1941-WAASX-SEC/K9
Data Paper PAK for Cisco 1900 series
SL-19-DATA-K9
Cisco 881 SRST Ethernet Security Router with FXS
FXO 802.11n FCC Compliant
C881SRST-K9
15.2(4)M4
securityk9 license
datak9 license
Functional Area
Product Description
Part Numbers
Software
WAN-aggregation Router
Aggregation Services 1002X Router
ASR1002X-5G-VPNK9
Aggregation Services 1002 Router
ASR1002-5G-VPN/K9
Aggregation Services 1001 Router
ASR1001-2.5G-VPNK9
IOS-XE 15.3(3)S
Advanced Enterprise
license
Cisco 3945 Security Bundle w/SEC license PAK
CISCO3945-SEC/K9
Cisco 3925 Security Bundle w/SEC license PAK
CISCO3925-SEC/K9
Data Paper PAK for Cisco 3900 series
SL-39-DATA-K9
Fixed WAN Remote-site Router
WAN Aggregation
WAN-aggregation Router
Appendix A: Product List
15.2(4)M4
securityk9 license
datak9 license
December 2013
91
LAN Access Layer
Functional Area
Product Description
Part Numbers
Software
Modular Access Layer Switch
Cisco Catalyst 4507R+E 7-slot Chassis with 48Gbps
per slot
WS-C4507R+E
3.4.0.SG(15.1-2SG)
IP Base license
Cisco Catalyst 4500 E-Series Supervisor Engine 7L-E
WS-X45-SUP7L-E
Cisco Catalyst 4500 E-Series 48 Ethernet
10/100/1000 (RJ45) PoE+ ports
WS-X4648-RJ45V+E
Cisco Catalyst 4500 E-Series 48 Ethernet
10/100/1000 (RJ45) PoE+,UPoE ports
WS-X4748-UPOE+E
Cisco Catalyst 3850 Series Stackable 48 Ethernet
10/100/1000 PoE+ ports
WS-C3850-48F
Cisco Catalyst 3850 Series Stackable 24 Ethernet
10/100/1000 PoE+ Ports
WS-C3850-24P
Cisco Catalyst 3850 Series 2 x 10GE Network Module
C3850-NM-2-10G
Cisco Catalyst 3850 Series 4 x 1GE Network Module
C3850-NM-4-1G
Cisco Catalyst 3750-X Series Stackable 48 Ethernet
10/100/1000 PoE+ ports
WS-C3750X-48PF-S
Cisco Catalyst 3750-X Series Stackable 24 Ethernet
10/100/1000 PoE+ ports
WS-C3750X-24P-S
Cisco Catalyst 3750-X Series Two 10GbE SFP+ and
Two GbE SFP ports network module
C3KX-NM-10G
Cisco Catalyst 3750-X Series Four GbE SFP ports
network module
C3KX-NM-1G
Cisco Catalyst 3560-X Series Standalone 48 Ethernet
10/100/1000 PoE+ ports
WS-C3560X-48PF-S
Cisco Catalyst 3560-X Series Standalone 24 Ethernet
10/100/1000 PoE+ ports
WS-C3560X-24P-S
Cisco Catalyst 3750-X Series Two 10GbE SFP+ and
Two GbE SFP ports network module
C3KX-NM-10G
Cisco Catalyst 3750-X Series Four GbE SFP ports
network module
C3KX-NM-1G
Cisco Catalyst 2960-S Series 48 Ethernet
10/100/1000 PoE+ ports and Two 10GbE SFP+ Uplink
ports
WS-C2960S-48FPD-L
Cisco Catalyst 2960-S Series 48 Ethernet
10/100/1000 PoE+ ports and Four GbE SFP Uplink
ports
WS-C2960S-48FPS-L
Cisco Catalyst 2960-S Series 24 Ethernet
10/100/1000 PoE+ ports and Two 10GbE SFP+ Uplink
ports
WS-C2960S-24PD-L
Cisco Catalyst 2960-S Series 24 Ethernet
10/100/1000 PoE+ ports and Four GbE SFP Uplink
ports
WS-C2960S-24PS-L
Cisco Catalyst 2960-S Series Flexstack Stack Module
C2960S-STACK
Stackable Access Layer Switch
Standalone Access Layer Switch
Stackable Access Layer Switch
Appendix A: Product List
3.2.1SE(15.0-1EX1)
IP Base license
15.0(2)SE2
IP Base license
15.0(2)SE2
IP Base license
15.0(2)SE2
LAN Base license
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92
LAN Distribution Layer
Functional Area
Product Description
Part Numbers
Software
Modular Distribution Layer Virtual
Switch Pair
Cisco Catalyst 6500 E-Series 6-Slot Chassis
WS-C6506-E
Cisco Catalyst 6500 VSS Supervisor 2T with 2 ports
10GbE and PFC4
VS-S2T-10G
15.1(1)SY
IP services license
Cisco Catalyst 6500 4-port 40GbE/16-port 10GbE
Fiber Module w/DFC4
WS-X6904-40G-2T
Cisco Catalyst 6500 4-port 10GbE SFP+ adapter for
WX-X6904-40G module
CVR-CFP-4SFP10G
Cisco Catalyst 6500 24-port GbE SFP Fiber Module
w/DFC4
WS-X6824-SFP-2T
Cisco Catalyst 4507R+E 7-slot Chassis with 48Gbps
per slot
WS-C4507R+E
Cisco Catalyst 4500 E-Series Supervisor Engine 7-E,
848Gbps
WS-X45-SUP7-E
Cisco Catalyst 4500 E-Series 24-port GbE SFP Fiber
Module
WS-X4624-SFP-E
Cisco Catalyst 4500 E-Series 12-port 10GbE SFP+
Fiber Module
WS-X4712-SFP+E
Cisco Catalyst 3750-X Series Stackable 12 GbE SFP
ports
WS-C3750X-12S-E
Cisco Catalyst 3750-X Series Two 10GbE SFP+ and
Two GbE SFP ports network module
C3KX-NM-10G
Cisco Catalyst 3750-X Series Four GbE SFP ports
network module
C3KX-NM-1G
Modular Distribution Layer Switch
Stackable Distribution Layer Switch
Appendix A: Product List
3.4.0.SG(15.1-2SG)
Enterprise Services
license
15.0(2)SE2
IP Services license
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93
Appendix B:
Device Configuration Files
To view the configuration files from the CVD lab devices that we used to test this guide, please go to the
following URL:
http://cvddocs.com/fw/240-13
Appendix B: Device Configuration Files
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94
Appendix C: Changes
This appendix summarizes the changes to this guide since its last edition.
• Added support for Cisco 4451-X Integrated Services Router platform.
• Added a WAN-facing summary route for the remote-site network range. The summary route ensures
that default routing changes do not affect remote-site communication between WAN transports.
Appendix C: Changes
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95
Feedback
Please use the feedback form to send comments and
suggestions about this guide.
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ALL DESIGNS, SPECIFICATIONS, STATEMENTS, INFORMATION, AND RECOMMENDATIONS (COLLECTIVELY, “DESIGNS”) IN THIS MANUAL ARE PRESENTED “AS IS,”
WITH ALL FAULTS. CISCO AND ITS SUPPLIERS DISCLAIM ALL WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE WARRANTY OF MERCHANTABILITY, FITNESS FOR
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ADVISORS BEFORE IMPLEMENTING THE DESIGNS. RESULTS MAY VARY DEPENDING ON FACTORS NOT TESTED BY CISCO.
Any Internet Protocol (IP) addresses used in this document are not intended to be actual addresses. Any examples, command display output, and figures included in the
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© 2013 Cisco Systems, Inc. All rights reserved.
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
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B-0000245-1 12/13
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