Configuring Multiprotocol BGP Extensions forIP Multicast
Multiprotocol BGP Configuration Task List
IPC-354
Cisco IOS IP Configuration Guide
To inject prefixes from a routing protocol into multiprotocol BGP, use the following commands
beginning in global configuration mode:
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 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
Command Purpose
Step1 Router(config)# router bgp autonomous-system Configures a BGP routing process and places the
router in router configuration mode.
Step2 Router(config-router)# address-family ipv4 multicast Specifies the IP Version 4 address family type and
places the router in address family configuration
mode.
Step3 Router(config-router-a)# redistribute protocol
[process-id] [route-map map-name]
Specifies the routing protocol from which prefixes
should be redistributed into multiprotocol BGP. Issue
the exit command two times to return to global
configuration mode.
Step4 Router(config)# route-map map-tag [permit | deny]
[sequence-number]
Defines a route map and places the router in route
map configuration mode.
Follow this step with a match command.
Step5 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.