Cisco Systems 78-11741-02 Configuring Dvmrp Interoperability with Multiprotocol BGP, IPC-354

Configuring Multiprotocol BGP Extensions for IP Multicast

Multiprotocol BGP Configuration Task List

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	Configures a BGP routing process and places the
		router in router configuration mode.
Step 2
	Router(config-router)#address-family ipv4 multicast	Specifies the IP Version 4 address family type and
		places the router in address family configuration
		mode.
Step 3
	Router(config-router-a)# redistribute protocol	Specifies the routing protocol from which prefixes
	[process-id][route-mapmap-name]	should be redistributed into multiprotocol BGP. Issue
		the exit command two times to return to global
		configuration mode.
Step 4
	Router(config)# route-map map-tag[permit deny]	Defines a route map and places the router in route
	[sequence-number]	map configuration mode.
		Follow this step with a match command.
Step 5
	Router(config-route-map)# match ip-address	Distributes any prefixes that have a destination
	access-list-number	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-mapcommand 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-mapcommand, as shown.

See the “Multiprotocol BGP Route Redistribute 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 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

Cisco IOS IP Configuration Guide

IPC-354