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Cisco IOS Software Releases 12.0 T

Multiprotocol BGP Extensions for IP Multicast

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Table Of Contents

Multiprotocol BGP Extensions for IP Multicast

Feature Overview

Benefits

Restrictions

Related Features and Technologies

Related Documents

Supported Platforms

Supported Standards, MIBs, and RFCs

Prerequisites

Configuration Tasks

Understanding NLRI Keywords and Address Families

Configuring a Multiprotocol BGP Peer

Configuring a Multiprotocol BGP Peer Group

Advertising Routes into Multiprotocol BGP

Configuring Route Maps for Multiprotocol BGP Prefixes

Redistributing Prefixes into Multiprotocol BGP

Configuring DVMRP Interoperability with Multiprotocol BGP

Redistributing Multiprotocol BGP Routes into DVMRP

Redistributing DVMRP Routes into Multiprotocol BGP

Configuring a Multiprotocol BGP Route Reflector

Configuring Aggregate Multiprotocol BGP Addresses

Verifying Multiprotocol BGP Configuration and Operation

Configuration Examples

Multiprotocol BGP Peer Examples

Multiprotocol BGP Peer Group Examples

Multiprotocol BGP Network Advertisement Examples

Multiprotocol BGP Route Map Examples

Multiprotocol BGP Route Redistribution Examples

Multiprotocol BGP Route Reflector Examples

Aggregate Multiprotocol BGP Address Examples

Command Reference

address-family ipv4

address-family vpnv4

aggregate-address

distance bgp

distance mbgp

ip dvmrp metric

ip multicast cache-headers

match nlri

neighbor peer-group (creating)

neighbor remote-as

neighbor route-map

network (BGP and multiprotocol BGP)

redistribute dvmrp

set nlri

show ip bgp ipv4 multicast

show ip bgp ipv4 multicast summary

show ip mbgp

show ip mbgp summary

Debug Commands

debug ip mbgp dampening

debug ip mbgp updates

Glossary


Multiprotocol BGP Extensions for IP Multicast

This feature module describes the multiprotocol Border Gateway Protocol (BGP) feature and includes the following sections:

•Feature Overview

•Supported Platforms

•Supported Standards, MIBs, and RFCs

•Prerequisites

•Configuration Tasks

•Configuration Examples

•Command Reference

•Debug Commands

•Glossary

Feature Overview

The multiprotocol BGP feature adds capabilities to BGP to enable multicast routing policy throughout the Internet and to connect multicast topologies within and between BGP autonomous systems. That is, multiprotocol BGP is an enhanced BGP that carries IP multicast routes. BGP carries two sets of routes, one set for unicast routing and one set for multicast routing. The routes associated with multicast routing are used by the Protocol Independent Multicast (PIM) to build data distribution trees.

Multiprotocol BGP is useful when you want a link dedicated to multicast traffic, perhaps to limit which resources are used for which traffic. Perhaps you want all multicast traffic exchanged at one network access point (NAP). Multiprotocol BGP allows you to have a unicast routing topology different from a multicast routing topology. Thus, you have more control over your network and resources.

In BGP, the only way to perform interdomain multicast routing was to use the BGP infrastructure that was in place for unicast routing. If those routers were not multicast capable, or there were differing policies where you wanted multicast traffic to flow, multicast routing could not be supported without multiprotocol BGP.

Note It is possible to configure BGP peers that exchange both unicast and multicast network layer reachability information (NLRI), but you cannot connect multiprotocol BGP clouds with a BGP cloud. That is, you cannot redistribute multiprotocol BGP routes into BGP.

Figure 1 illustrates a simple example of unicast and multicast topologies that are incongruent, and therefore are not be possible without multiprotocol BGP.

Autonomous systems 100, 200, and 300 are each connected to two NAPs that are FDDI rings. One is used for unicast peering (and therefore the exchanging of unicast traffic). The Multicast Friendly Interconnect (MFI) ring is used for multicast peering (and therefore the exchanging of multicast traffic). Each router is unicast- and multicast-capable.

Figure 1 Incongruent Unicast and Multicast Routes

Figure 2 is a topology of unicast-only routers and multicast-only routers. The two routers on the left are unicast-only routers (that is, they do not support or are not configured to perform multicast routing). The two routers on the right are multicast-only routers. Routers A and B support both unicast and multicast routing. The unicast-only and multicast-only routers are connected to a single NAP.

In Figure 2, only unicast traffic can travel from Router A to the unicast routers to Router B and back. Multicast traffic could not flow on that path, so another routing table is required. Multicast traffic uses the path from Router A to the multicast routers to Router B and back.

Figure 2 illustrates a multiprotocol BGP environment with a separate unicast route and multicast route from Router A to Router B. Multiprotocol BGP allows these routes to be noncongruent. Both of the autonomous systems must be configured for internal multiprotocol BGP.

A multicast routing protocol, such as PIM, uses the multicast BGP database to perform Reverse Path Forwarding (RPF) lookups for multicast-capable sources. Thus, packets can be sent and accepted on the multicast topology but not on the unicast topology.

Figure 2 Multicast BGP Environment

Benefits

Multiprotocol BGP offers the following benefits:

•A network can support incongruent unicast and multicast topologies.

•A network can support congruent unicast and multicast topologies that have different policies (BGP filtering configurations).

•A network can carry routing information for multiple network layer protocol address families (for example, IPv4 or VPNv4) as specified in RFC 1700, Assigned Numbers.

•A network that is backward compatible—routers that support the multiprotocol extensions can interoperate with routers that do not support the extensions.

•All of the routing policy capabilities of BGP can be applied to multiprotocol BGP.

•All of the BGP commands can be used with multiprotocol BGP.

Restrictions

You cannot connect multiprotocol BGP clouds with a BGP cloud. That is, you cannot redistribute multiprotocol BGP routes into BGP.

Related Features and Technologies

This feature is related to the existing BGP feature, which is documented in the Cisco IOS IP and IP Routing Configuration Guide and the Cisco IOS IP and IP Routing Command Reference.

Related Documents

•Cisco IOS IP and IP Routing Configuration Guide, Release 12.1

•Cisco IOS IP and IP Routing Command Reference, Release 12.1

•RFC 2283, Multiprotocol Extensions for BGP-4

Supported Platforms

This feature can run on all Cisco platforms, but it is officially supported on only the following platforms:

•Cisco 4500

•Cisco 7200

•Cisco 7500

•RSP 7000

Supported Standards, MIBs, and RFCs

Standards

No new or modified standards are supported by this feature.

MIBs

No new or modified MIBs are supported by this feature.

To obtain lists of MIBs supported by platform and Cisco IOS releases and to download MIB modules, go to the Cisco MIB web site on Cisco Connection Online (CCO) at http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml.

RFCs

•RFC 2283, Multiprotocol Extensions for BGP-4

Prerequisites

This document assumes you are familiar with BGP and IP multicast routing. For more information, refer to the "Configuring BGP" and "Configuring IP Multicast Routing" chapters of the Cisco IOS IP and IP Routing Configuration Guide.

Configuration Tasks

See the following sections for configuration tasks for this feature. Each task in the list is identified as either required or optional:

•Understanding NLRI Keywords and Address Families (Required)

•Configuring a Multiprotocol BGP Peer (Required)

•Configuring a Multiprotocol BGP Peer Group (Optional)

•Advertising Routes into Multiprotocol BGP (Required)

•Configuring Route Maps for Multiprotocol BGP Prefixes (Optional)

•Redistributing Prefixes into Multiprotocol BGP (Required)

•Configuring DVMRP Interoperability with Multiprotocol BGP (Optional)

•Configuring a Multiprotocol BGP Route Reflector (Optional)

•Configuring Aggregate Multiprotocol BGP Addresses (Optional)

•Verifying Multiprotocol BGP Configuration and Operation (Optional)

Understanding NLRI Keywords and Address Families

Multiprotocol BGP was introduced in Cisco IOS Release 11.1(20)CC and Cisco IOS Release 12.0(2)S prior to it being integrated into Cisco IOS Release 12.0(7)T. In Cisco IOS Release 11.1(20)CC and later releases and Cisco IOS Release 12.0(2)S and later releases, the Cisco IOS software uses NLRI keywords to enable multiprotocol BGP over a BGP session and to populate unicast BGP prefixes in the unicast database and multicast BGP prefixes in the multicast database. In Cisco IOS Release 12.0(7)T, the Cisco IOS software uses separate address families to enable multiprotocol BGP over a BGP session and to populate unicast BGP prefixes in the unicast database and multicast BGP prefixes in the multicast database.

Cisco IOS Release 12.0(7)T does not support the NLRI keywords. However, for backward compatibility, the NLRI keyword configuration of a Cisco router is automatically converted to an address family configuration when a router is upgraded to Cisco IOS Release 12.0(7)T. The following example shows an NLRI keyword configuration for a Cisco router that is running Cisco IOS Release 12.0(8)S: 

router bgp 5

  no synchronization

  network 172.16.214.0 mask 255.255.255.0 nlri unicast multicast

  neighbor 172.16.214.34 remote-as 5

  neighbor 172.16.214.38 remote-as 2 nlri unicast multicast

  neighbor 172.16.214.42 remote-as 5

  neighbor 172.16.214.59 remote-as 5

no auto-summary

The following example shows the resulting address family configuration after the same router is upgraded to Cisco IOS Release 12.0(7)T: 

router bgp 5

  no synchronization

  network 172.16.214.0 mask 255.255.255.0

  neighbor 172.16.214.34 remote-as 5

  neighbor 172.16.214.38 remote-as 2

  neighbor 172.16.214.42 remote-as 5

  neighbor 172.16.214.59 remote-as 5

no auto-summary

Note Although supported in Cisco IOS Release 12.0(7)T, this feature module does not explain how to configure the BGP-4 extensions for Virtual Private Network (VPN) address family prefixes. Configuring VPN address family prefixes will be explained in a later release of the Cisco IOS IP and IP Routing Configuration Guide and the Cisco IOS IP and IP Routing Command Reference.

Configuring a Multiprotocol BGP Peer

To configure multiprotocol BGP between two routers, use the following commands beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# router bgp autonomous-system

Router(config-router)#

Configures a BGP routing process and places the router in router configuration mode.

Step 2 

Router(config-router)# neighbor ip-address remote-as autonomous-system-number

Adds the IP address of the neighbor in the remote autonomous system to the multiprotocol BGP neighbor table of the local router.

Step 3 

Router(config-router)# address-family ipv4 multicast

Router(config-router-af)#

Specifies the IPv4 address family type and places the router in address family configuration mode.

Step 4 

Router(config-router-af)# neighbor {ip-address | peer-group-name} activate

Enables the neighbor to exchange prefixes for the specified family type with the local router.

Note By default, neighbors that are defined using the neighbor remote-as command in router configuration mode exchange only unicast address prefixes. To exchange other address prefix types, such as multicast and VPNv4, neighbors must also be activated using the neighbor activate command in address family configuration mode, as shown.

See the "Multiprotocol BGP Peer Examples" section for multiprotocol BGP peer configuration examples.

Configuring a Multiprotocol BGP Peer Group

To configure a peer group to perform multiprotocol BGP routing, use the following commands beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# router bgp autonomous-system

Router(config-router)#

Configures a BGP routing process and places the router in router configuration mode.

Step 2 

Router(config-router)# neighbor peer-group-name peer-group

Creates a multiprotocol BGP peer group.

Step 3 

Router(config-router)# neighbor ip-address remote-as autonomous-system-number

Adds the IP address of the neighbor in the remote autonomous system to the multiprotocol BGP neighbor table of the local router.

Step 4 

Router(config-router)# neighbor ip-address peer-group peer-group-name

Assigns the IP address of a BGP neighbor to a peer group.

Step 5 

Router(config-router)# address-family ipv4 multicast

Router(config-router-af)#

Specifies IPv4 address family type and places the router in address family configuration mode.

Step 6 

Router(config-router-af)# neighbor peer-group-name activate

Enables the peer group to exchange prefixes for the specified family type with the neighbor and the local router.

Step 7 

Router(config-router-af)# neighbor ip-address peer-group peer-group-name

Assigns the IP address of a BGP neighbor to a peer group.

Note By default, neighbors that are defined using the neighbor remote-as command in router configuration mode exchange only unicast address prefixes. To exchange other address prefix types, such as multicast and VPNv4, neighbors must also be activated using the neighbor activate command in address family configuration mode, as shown.

Note Peer groups that are defined in router configuration mode using the neighbor peer-group command exchange only unicast address prefixes by default. To exchange other address prefix types, such as multicast, peer groups must be defined in address family configuration mode using the neighbor activate command, as shown.

Members of a peer group automatically inherit the address prefix configuration of the peer group.

Refer to the section "Configure BGP Peer Groups" of the "Configuring BGP" chapter in the Cisco IOS IP and IP Routing Configuration Guide for information and instructions on assigning options to the peer group and making a BGP or multiprotocol BGP neighbor a member of the peer group. See the "Multiprotocol BGP Peer Group Examples" section for multiprotocol BGP peer group configuration examples.

Advertising Routes into Multiprotocol BGP

To advertise (inject) a network number and mask into multiprotocol BGP, use the following commands beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# router bgp autonomous-system

Router(config-router)#

Configures a BGP routing process and places the router in router configuration mode.

Step 2 

Router(config-router)# address-family ipv4 multicast

Router(config-router-af)#

Specifies IPv4 address family type and places the router in address family configuration mode.

Step 3 

Router(config-router-af)# network network-number [mask network-mask]

Advertises (injects) this network number and mask into the multicast BGP database. (The routes must first be found in the unicast forwarding table.) Specifically, the network number and mask are injected into the multicast database for the address family specified in the previous step.

Routes are tagged from the specified network as "local origin."

Note Networks that are defined in router configuration mode using the network command are injected into the unicast database by default. To inject a network into another database, such as the multicast database, the network must be defined in address family configuration mode using the network command, as shown.

See the "Multiprotocol BGP Network Advertisement Examples" section for multiprotocol BGP network advertisement configuration examples.

Configuring Route Maps for Multiprotocol BGP Prefixes

To configure a route map for multiprotocol BGP prefixes, use the following commands beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# router bgp autonomous-system

Router(config-router)#

Configures a BGP routing process and places the router in router configuration mode.

Step 2 

Router(config-router)# neighbor ip-address remote-as autonomous-system-number

Adds the IP address of the neighbor in the remote autonomous system to the multiprotocol BGP neighbor table of the local router.

Step 3 

Router(config-router)# address-family ipv4 multicast

Router(config-router-af)#

Specifies IPv4 address family type and places the router in address family configuration mode.

Step 4 

Router(config-router-af)# neighbor ip-address activate

Enables the address family for the neighbor in the remote autonomous system.

Step 5 

Router(config-router-af)# neighbor ip-address route-map route-map-name {in | out}

Applies a route map to incoming or outgoing routes.

Step 6 

Router(config)# route-map map-tag [permit | deny] [sequence-number]

Defines a route map.

Step 7 

Router(config-route-map)# match ip-address access-list-number

Distributes any routes that have a destination network number address permitted by a standard or extended access list, or performs policy routing on packets.

Note By default, neighbors that are defined using the neighbor remote-as command in router configuration mode exchange only unicast address prefixes. To exchange other address prefix types, such as multicast and VPNv4, neighbors must also be activated using the neighbor activate command in address family configuration mode, as shown.

Note Route maps that are applied in router configuration mode using the neighbor route-map command are applied to unicast address prefixes by default. Route maps for other address families, such as multicast, must be applied in address family configuration mode using the neighbor route-map command, as shown. The route maps are applied either as the inbound or outbound routing policy for neighbors under each address family. Configuring separate route maps under each address family simplifies managing complicated or different policies for each address family.

See the "Multiprotocol BGP Route Map Examples" section for multiprotocol BGP route map configuration examples.

Redistributing Prefixes into Multiprotocol BGP

Redistribution is the process of injecting prefixes from one routing protocol into another routing protocol. The tasks in this section explain how to inject prefixes from a routing protocol into multiprotocol BGP. Specifically, prefixes that are redistributed into multiprotocol BGP using the redistribute command are injected into the unicast database, the multicast database, or both.

To inject prefixes from a routing protocol into multiprotocol BGP, use the following commands beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# router bgp autonomous-system

Router(config-router)#

Configures a BGP routing process and places the router in router configuration mode.

Step 2 

Router(config-router)# address-family ipv4 multicast

Router(config-router-af)#

Specifies IPv4 address family type and places the router in address family configuration mode.

Step 3 

Router(config-router-af)# redistribute protocol [process-id] [route-map map-name]

Specifies the routing protocol from which prefixes should be redistributed into multiprotocol BGP.

Step 4 

Router(config)# route-map map-tag [permit | deny] [sequence-number]

Router(config-route-map)#

Defines a route map and places the router in route map configuration mode.

Follow this step with a match command.

Step 5 

Router(config-route-map)# match ip-address access-list-number

Distributes any prefixes that have a destination network number address permitted by a standard or extended access list, or performs policy routing on packets.

Note Route maps that are applied in router configuration mode using the redistribute route-map command are applied to unicast address prefixes by default. Route maps for other address families, such as multicast, must be applied in address family configuration mode using the redistribute route-map command, as shown.

See the "Multiprotocol BGP Route Redistribution Examples" section for multiprotocol BGP route redistribution configuration examples.

Configuring DVMRP Interoperability with Multiprotocol BGP

Cisco multicast routers using PIM can interoperate with non-Cisco multicast routers that use the Distance Vector Multicast Routing Protocol (DVMRP).

PIM routers dynamically discover DVMRP multicast routers on attached networks. Once a DVMRP neighbor has been discovered, the router caches DVMRP routes that the neighbor sends. Those routes describe sources in a DVMRP cloud that want their packets to be received by receivers outside of this routing domain. Multiprotocol BGP allows the source prefixes of those sources to be known outside of the routing domain.

The router periodically sends DVMRP Report messages advertising the unicast sources reachable in the PIM domain.

Redistributing Multiprotocol BGP Routes into DVMRP

By default, no multiprotocol BGP routes are redistributed into DVMRP. However, you can configure all multiprotocol BGP routes to be redistributed into DVMRP with a specified metric. Furthermore, to redistribute only certain multiprotocol BGP routes into DVMRP, you can configure the metric and subject it to route map conditions. If you supply a route map, you can specify various match criteria options for the multiprotocol BGP routes. If the route passes the route map, then the route is redistributed into DVMRP.

If there are multicast sources in other routing domains that are known via multiprotocol BGP and there are receivers in a DVMRP cloud, they will want to receive packets from those sources. Therefore, you need to redistribute the multiprotocol BGP prefix routes into DVMRP. This will be the scenario when distributing multiprotocol BGP prefixes into the MBONE.

To redistribute multiprotocol BGP routes into DVMRP, use the following command in interface configuration mode:

Command
Purpose

Router(config-if)# ip dvmrp metric metric [route-map map-name] mbgp

Redistributes multiprotocol BGP routes into DVMRP with a specified metric. An optional route map controls which routes are redistributed; otherwise, all multiprotocol BGP routes are redistributed.


Redistributing DVMRP Routes into Multiprotocol BGP

If there are multicast sources in a DVMRP routing domain that need to reach receivers in multiprotocol BGP routing domains, you need to redistribute DVMRP prefixes into multiprotocol BGP. If you supply a route map, you can also use the set commands to specify various BGP attribute settings.

To redistribute DVMRP prefixes into multiprotocol BGP, use the following command in address family configuration mode:

Command
Purpose

Router(config-router-af)# redistribute dvmrp [route-map map-name]

Redistributes DVMRP routes into multiprotocol BGP.


To redistribute DVMRP prefixes into multiprotocol BGP, use the following command in router configuration mode:

Command
Purpose

Router(config-router)# redistribute dvmrp [route-map map-name]

Redistributes DVMRP routes into multiprotocol BGP.


See the "Multiprotocol BGP Route Redistribution Examples" section for multiprotocol BGP route redistribution configuration examples.

Configuring a Multiprotocol BGP Route Reflector

To configure a local router as a route reflector of multiprotocol BGP prefixes, use the following commands beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# router bgp autonomous-system

Router(config-router)#

Configures a BGP routing process and places the router in router configuration mode.

Step 2 

Router(config-router)# neighbor ip-address remote-as autonomous-system-number

Adds the IP address of the neighbor in the remote autonomous system to the multiprotocol BGP neighbor table of the local router.

Step 3 

Router(config-router)# address-family ipv4 multicast

Router(config-router-af)#

Specifies an IPv4 address family type and places the router in address family configuration mode.

Step 4 

Router(config-router-af)# neighbor ip-address activate

Enables the specified address family for the neighbor in the remote autonomous system.

Step 5 

Router(config-router-af)# neighbor ip-address route-reflector-client

Configures the router as a route reflector of prefixes for the specified address family type and configures the specified neighbor as its client.

Note By default, neighbors that are defined using the neighbor remote-as command in router configuration mode exchange only unicast address prefixes. To exchange other address prefix types, such as multicast and VPNv4, neighbors must also be activated using the neighbor activate command in address family configuration mode, as shown.

Note Route reflectors and clients (neighbors or internal BGP peer groups) that are defined in router configuration mode using the neighbor route-reflector-client command reflect unicast address prefixes to and from those clients by default. To reflect prefixes for other address families, such as multicast, define the reflectors and clients in address family configuration mode using the neighbor route-reflector-client command, as shown.

See the "Multiprotocol BGP Route Reflector Examples" section for multiprotocol BGP route reflector configuration examples.

Configuring Aggregate Multiprotocol BGP Addresses

The tasks in this section explain how to configure an aggregate address for multiprotocol BGP. Specifically, the tasks in this section explain how to inject an aggregate address into the multicast database, the unicast database, or both.

To configure an aggregate address for multiprotocol BGP, use the following commands beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# router bgp autonomous-system

Router(config-router)#

Configures a BGP routing process and places the router in router configuration mode.

Step 2 

Router(config-router)# address-family ipv4 multicast

Router(config-router-af)#

Specifies IPv4 address family type and places the router in address family configuration mode.

Step 3 

Router(config-router-af)# aggregate-address address mask [as-set] [summary-only] [suppress-map map-name] [advertise-map map-name] [attribute-map map-name]

Configures an aggregate address with various options.

Note Aggregate addresses that are defined in router configuration mode using the aggregate-address as-set command are injected into the unicast database by default. To enter an aggregate address in another database, such as the multicast database, the aggregate address must be defined in address family configuration mode using the aggregate-address as-set command, as shown.

See the "Aggregate Multiprotocol BGP Address Examples" section for aggregate multiprotocol BGP address configuration examples.

Verifying Multiprotocol BGP Configuration and Operation

The following steps show an example of how to verify multiprotocol BGP configuration and operation:

Step 1 Enter the show ip bgp ipv4 multicast EXEC command to display information related to the multicast database: 

Router# show ip bgp ipv4 multicast


MBGP table version is 6, local router ID is 192.168.200.66

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal

Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop          Metric LocPrf Weight Path

*> 10.0.20.16/28     0.0.0.0                0      0 32768 i

*> 10.0.35.16/28     0.0.0.0                0      0 32768 i

*> 10.0.36.0/28      0.0.0.0                0      0 32768 i

*> 10.0.48.16/28     0.0.0.0                0      0 32768 i

*> 10.2.0.0/16       0.0.0.0                0      0 32768 i

*> 10.2.1.0/24       0.0.0.0                0      0 32768 i

*> 10.2.2.0/24       0.0.0.0                0      0 32768 i

*> 10.2.3.0/24       0.0.0.0                0      0 32768 i

*> 10.2.7.0/24       0.0.0.0                0      0 32768 i

*> 10.2.8.0/24       0.0.0.0                0      0 32768 i

*> 10.2.10.0/24      0.0.0.0                0      0 32768 i

*> 10.2.11.0/24      0.0.0.0                0      0 32768 i

*> 10.2.12.0/24      0.0.0.0                0      0 32768 i

*> 10.2.13.0/24      0.0.0.0                0      0 32768 i

Note For a description of each output display field, refer to the show ip bgp ipv4 multicast command in the "Command Reference" section of this feature module.

Step 2 Enter the show ip bgp ipv4 multicast summary EXEC command to display a summary of multicast database information: 

Router# show ip bgp ipv4 multicast summary


BGP router identifier 10.0.33.34, local AS number 34

BGP table version is 5, main routing table version 1

4 network entries and 6 paths using 604 bytes of memory

5 BGP path attribute entries using 260 bytes of memory

1 BGP AS-PATH entries using 24 bytes of memory

2 BGP community entries using 48 bytes of memory

2 BGP route-map cache entries using 32 bytes of memory

0 BGP filter-list cache entries using 0 bytes of memory

BGP activity 8/28 prefixes, 12/0 paths, scan interval 15 secs


Neighbor        V    AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down  State/PfxRcd

10.0.33.35      4    35     624     624        5    0    0 10:13:46        3

Step 3 Enter the debug ip mbgp dampening EXEC command to log the route flap dampening activity: 

Router# debug ip mbgp dampening


BGP: charge penalty for 173.19.0.0/16 path 49 with halflife-time 15 reuse/suppress 
750/2000

BGP: flapped 1 times since 00:00:00. New penalty is 1000

BGP: charge penalty for 173.19.0.0/16 path 19 49 with halflife-time 15 reuse/suppress 
750/2000

BGP: flapped 1 times since 00:00:00. New penalty is 1000

Step 4 Enter the debug ip mbgp updates EXEC command to log the multiprotocol BGP-related information passed in BGP Update messages: 

Router# debug ip mbgp updates


BGP: NEXT_HOP part 1 net 200.10.202.0/24, neigh 171.69.233.49, next 171.69.233.34

BGP: 171.69.233.49 send UPDATE 200.10.202.0/24, next 171.69.233.34, metric 0, path 33 34 
19 49 109 65000 297 1239 1800 3597

BGP: NEXT_HOP part 1 net 200.10.228.0/22, neigh 171.69.233.49, next 171.69.233.34

BGP: 171.69.233.49 rcv UPDATE about 222.2.2.0/24, next hop 171.69.233.49, path 49 109 
metric 0

BGP: 171.69.233.49 rcv UPDATE about 131.103.0.0/16, next hop 171.69.233.49, path 49 109 
metric 0

BGP: 171.69.233.49 rcv UPDATE about 206.205.242.0/24, next hop 171.69.233.49, path 49 109 
metric 0

Step 5 Enter the show ip mpacket quality EXEC command to display the quality of Real-Time Transport Protocol (RTP) data based on packets captured in the IP multicast cache header buffer: 

Router# show ip mpacket 224.2.163.188 quality


Calculating RTP data quality for 224.2.163.188

  Session: UO Presents KKNU New Country

  Source: 128.223.83.27 (sand.uoregon.edu), Port: 23824

    Packets received: 83, lost: 5, loss percentage: 5.6%

    Packets misordered: 7, average loss gap: 0

Configuration Examples

This section provides the following multiprotocol BGP configuration examples:

•Multiprotocol BGP Peer Examples

•Multiprotocol BGP Peer Group Examples

•Multiprotocol BGP Network Advertisement Examples

•Multiprotocol BGP Route Map Examples

•Multiprotocol BGP Route Redistribution Examples

•Multiprotocol BGP Route Reflector Examples

•Aggregate Multiprotocol BGP Address Examples

Multiprotocol BGP Peer Examples

The following example shows how to use an address family to configure a neighbor as both unicast and multicast capable: 

router bgp 100

address-family ipv4 unicast

  neighbor 10.1.1.1 activate


router bgp 100

 address-family ipv4 multicast

  neighbor 10.1.1.1 activate

Multiprotocol BGP Peer Group Examples

The following example shows how to use an address family to configure a peer group so that all members of the peer group are both unicast and multicast capable: 

router bgp 100

neighbor 10.1.1.1 remote-as 1

neighbor 12.2.2.2 remote-as 2

address-family ipv4 unicast

  neighbor mygroup peer-group

  neighbor 10.1.1.1 peer-group mygroup

  neighbor 12.2.2.2 peer-group mygroup


router bgp 100

neighbor 10.1.1.1 remote-as 1

neighbor 12.2.2.2 remote-as 2

address-family ipv4 multicast

  neighbor mygroup peer-group

  neighbor 10.1.1.1 peer-group mygroup

  neighbor 12.2.2.2 peer-group mygroup

  neighbor 10.1.1.1 activate

  neighbor 12.2.2.2 activate

Multiprotocol BGP Network Advertisement Examples

The following examples show how to use an address family to inject a network number and mask into the unicast database and the multicast database: 

router bgp 100

 address-family ipv4 unicast

  neighbor 10.0.0.0  255.0.0.0

router bgp 100

 address-family ipv4 multicast

  neighbor 10.0.0.0  255.0.0.0

Multiprotocol BGP Route Map Examples

The following example shows how to use an address family to configure BGP so that any unicast and multicast routes from neighbor 10.1.1.1 are accepted if they match access list 1: 

router bgp 109

neighbor 10.1.1.1 remote-as 1

address-family ipv4 unicast

 neighbor 10.1.1.1 route-map filter-some-multicast in


router bgp 109

neighbor 10.1.1.1 remote-as 1

address-family ipv4 multicast

 neighbor 10.1.1.1 route-map filter-some-multicast in

 neighbor 10.1.1.1 activate


route-map filter-some-multicast

 match ip address 1

Multiprotocol BGP Route Redistribution Examples

The following example shows how to use an address family to redistribute DVMRP routes that match access list 1 into the multicast database and the unicast database of the local router: 

router bgp 109

address-family ipv4 unicast

 redistribute dvmrp route-map dvmrp-into-mbgp


router bgp 109

address-family ipv4 multicast

 redistribute dvmrp route-map dvmrp-into-mbgp


route-map dvmrp-into-mbgp

 match ip address 1

Multiprotocol BGP Route Reflector Examples

The following example show how to use an address family to configure internal BGP peer 10.1.1.1 as a route-reflector client for both unicast and multicast prefixes: 

router bgp 109

 address-family ipv4 unicast

  neighbor 10.1.1.1 activate

  neighbor 10.1.1.1 route-reflector-client


router bgp 109

 address-family ipv4 multicast

  neighbor 10.1.1.1 activate

  neighbor 10.1.1.1 route-reflector-client

Aggregate Multiprotocol BGP Address Examples

The following example show how to use an address family to configure an aggregate multiprotocol BGP address entry in both the unicast database and the multicast database: 

router bgp 109

 address-family ipv4 unicast

  aggregate-address 172.16.0.0 255.0.0.0 as-set

router bgp 109

 address-family ipv4 multicast

  aggregate-address 172.16.0.0 255.0.0.0 as-set

Command Reference

This section documents new or modified commands. All other commands used with multiprotocol BGP are documented in the Cisco IOS Release 12.1 command reference publications.

•address-family ipv4

•address-family vpnv4

•aggregate-address

•distance bgp

•ip dvmrp metric

•ip multicast cache-headers

•neighbor peer-group (creating)

•neighbor remote-as

•neighbor route-map

•network (BGP and multiprotocol BGP)

•redistribute dvmrp

•show ip bgp ipv4 multicast

•show ip bgp ipv4 multicast summary

Commands in this feature module that have been replaced by new or existing commands are no longer documented. Table 1 maps the old commands with their replacements.

Table 1 Mapping Old Commands with Replacement Commands

Old Command
Replacement Command

distance mbgp

distance bgp

match nlri

address-family ipv4

address-family vpnv4

set nlri

address-family ipv4

address-family vpnv4

show ip mbgp

show ip bgp ipv4 multicast

show ip mbgp summary

show ip bgp ipv4 multicast summary


address-family ipv4

To enter address family configuration mode for configuring routing sessions, such as Border Gateway Protocol (BGP), that use standard IPv4 address prefixes, use the address-family ipv4 router configuration command. To disable address family configuration mode, use the no form of this command.

address-family ipv4 [multicast | unicast [vrf vrf-name]

no address-family ipv4 [multicast | unicast | vrf vrf-name]

Syntax Description

multicast

(Optional) Specifies IPv4 multicast address prefixes.

unicast

(Optional) Specifies IPv4 unicast address prefixes.

vrf vrf-name

(Optional) Specifies the name of the virtual routing/forwarding instance (VRF) to associate with subsequent IPv4 address family configuration mode commands.


Defaults

IPv4 address prefixes are not enabled. Unicast address prefixes are the default when IPv4 address prefixes are configured.

Command Modes

Router configuration

Command History

Release
Modification

12.0(5)T

This command was introduced.


Usage Guidelines

The address-family ipv4 command places the router in address family configuration mode (prompt: config-router-af), from which you can configure routing sessions that use standard IPv4 address prefixes. To leave address family configuration mode and return to router configuration mode, type exit.

Routing information for address family IPv4 is advertised by default when you configure a BGP routing session using the neighbor remote-as command unless you execute the no bgp default ipv4-unicast command.

The address-family ipv4 command replaces the match nlri and set nlri commands.

Examples

The following example places the router in address family configuration mode for the IPv4 address family: 

Router(config)# router bgp 100

Router(config-router)# address-family ipv4

Router(config-router-af)#

The following example places the router in address family configuration mode and specifies multicast address prefixes for the IPv4 address family: 

Router(config)# router bgp 100

Router(config-router)# address-family ipv4 multicast

Router(config-router-af)#

The following example places the router in address family configuration mode and specifies unicast address prefixes for the IPv4 address family: 

Router(config)# router bgp 100

Router(config-router)# address-family ipv4 unicast

Router(config-router-af)#

The following example places the router in address family configuration mode and specifies cisco as the name of the VRF instance to associate with subsequent IPv4 address family configuration mode commands: 

Router(config)# router bgp 100

Router(config-router)# address-family ipv4 vrf cisco

Router(config-router-af)#

Use this form of the command, which specifies a VRF, only to configure routing exchanges between provider edge (PE) and customer edge (CE) devices.

Related Commands

Command
Description

address-family vpnv4

Places the router in address family configuration mode for configuring routing sessions such as BGP, RIP, or static routing sessions that use standard VPNv4 address prefixes.

neighbor activate

Enables the exchange of information with a BGP neighboring router.


address-family vpnv4

To enter address family configuration mode for configuring routing sessions, such as Border Gateway Protocol (BGP), that use standard VPNv4 address prefixes, use the address-family vpnv4 router configuration command. To disable address family configuration mode, use the no form of this command.

address-family vpnv4 [unicast]

no address-family vpnv4 [unicast]

Syntax Description

unicast

(Optional) Specifies VPNv4 unicast address prefixes.


Defaults

VPNv4 address prefixes are not enabled. Unicast address prefixes are the default when VPNv4 address prefixes are configured.

Command Modes

Router configuration

Command History

Release
Modification

12.0(5)T

This command was introduced.


Usage Guidelines

The address-family vpnv4 command places the router in address family configuration mode (prompt: config-router-af), from which you can configure routing sessions that use VPNv4 address prefixes. To leave address family configuration mode and return to router configuration mode, type exit.

The address-family vpnv4 command replaces the match nlri and set nlri commands.

Examples

The following example places the router in address family configuration mode for the VPNv4 address family: 

Router(config)# router bgp 100

(config-router)# address-family vpnv4

(config-router-af)#

The following example places the router in address family configuration mode for the unicast VPNv4 address family: 

Router(config)# router bgp 100

(config-router)# address-family vpnv4 unicast

(config-router-af)#

Related Commands

Command
Description

address-family ipv4

Places the router in address family configuration mode for configuring routing sessions such as BGP, RIP, or static routing sessions that use standard IPv4 address prefixes.

neighbor activate

Enables the exchange of information with a BGP neighboring router.


aggregate-address

To create an aggregate entry in a Border Gateway Protocol (BGP) or multicast BGP database, use the aggregate-address command in address family or router configuration mode. To disable this function, use the no form of this command.

aggregate-address address mask [as-set] [summary-only] [suppress-map map-name] [advertise-map map-name] [attribute-map map-name]

no aggregate-address address mask [as-set] [summary-only] [suppress-map map-name] [advertise-map map-name] [attribute-map map-name]

Syntax Description

address

Aggregate address.

mask

Aggregate mask.

as-set

(Optional) Generates autonomous system set path information.

summary-only

(Optional) Filters all more-specific routes from updates.

suppress-map map-name

(Optional) Name of the route map used to select the routes to be suppressed.

advertise-map map-name

(Optional) Name of the route map used to select the routes to create AS-SET origin communities.

attribute-map map-name

(Optional) Name of route map used to set the attribute of the aggregate route.


Defaults

Disabled

Command Modes

Address family configuration

Router configuration

Command History

Release
Modification

10.0

This command was introduced.

11.1(20)CC

The nlri unicast, nlri multicast, and nlri unicast multicast keywords were added.

12.0(2)S

The nlri unicast, nlri multicast, and nlri unicast multicast keywords were added.

12.0(7)T

The nlri unicast, nlri multicast, and nlri unicast multicast keywords were removed.

Address family configuration mode was added.


Usage Guidelines

You can implement aggregate routing in BGP and multiprotocol BGP either by redistributing an aggregate route into BGP or multiprotocol BGP, or by using this conditional aggregate routing feature.

Using the aggregate-address command with no arguments will create an aggregate entry in the BGP or multicast BGP database if there are any more-specific BGP or multiprotocol BGP routes available that fall in the specified range. The aggregate route will be advertised as coming from your autonomous system and will have the atomic aggregate attribute set to show that information might be missing. (By default, the atomic aggregate attribute is set unless you specify the as-set keyword.)

Using the as-set keyword creates an aggregate entry using the same rules that the command follows without this keyword, but the path advertised for this route will be an AS_SET consisting of all elements contained in all paths that are being summarized. Do not use this form of the aggregate-address command when aggregating many paths, because this route must be continually withdrawn and re