The following shows an example S- or K-Series device configuration that sets up an inter-domain MSDP peering relationship.
Define the loop back or VLAN interfaces for PIM RP / MSDP peers. In the example, loop.0.1 is used as PIM RP/ MSDP peer.
[On router A:]
interface loop.0.1 ip address 121.1.1.1 255.255.255.0 primary no shutdown exit
[On router B:]
interface loop.0.1 ip address 122.2.2.2 255.255.255.0 primary no shutdown exit
Define a PIM RP for each domain.
[On router A:]
ip pim bsr-candidate 121.1.1.1 ip pim rp-candidate 121.1.1.1 224.0.0.0 240.0.0.0
[On router B:]
ip pim bsr-candidate 122.2.2.2 ip pim rp-candidate 122.2.2.2 224.0.0.0 240.0.0.0
Configure BGP for each domain.
[On router A:]
router bgp 5100 bgp router-id 121.1.1.1 neighbor 122.2.2.2 remote-as 5200 neighbor 122.2.2.2 ebgp-multihop 10 neighbor 122.2.2.2 update-source 121.1.1.1 redistribute connected exit
[On router B:]
router bgp 5200 bgp router-id 122.2.2.2 neighbor 121.1.1.1 remote-as 5100 neighbor 121.1.1.1 ebgp-multihop 10 neighbor 121.1.1.1 update-source 122.2.2.2 redistribute connected exit
Configure OSPF for each domain so that unicast routes work for PIM. This is basic for PIM.
Configure MSDP peers between the two domains.
[On router A:]
ip msdp peer 122.2.2.2 connect-source loop.0.1 remote-as 5200
[On router B:]
ip msdp peer 121.1.1.1 connect-source loop.0.1 remote-as 5100