Configuring Anycast RP in MSDP

Anycast RP is a solution for fast convergence of RP routing in the event of an RP router failure. All members of an Anycast RP set are registered peers, and when a source registers with one RP in the set, it sends an SA message to the other RPs in the set so that they all have the available information about active sources.

Anycast RP has been available for PIM RPs in Extreme Networks, as described in Anycast-RP. With MSDP configured in your network, the Anycast RP solution can be applied to MSDP RPs in the same way. Please note that MSDP Anycast RP and PIM Anycast RP are mutually exclusive, there can be only one or the other Anycast RP solution operating in a domain. If you already have PIM Anycast RP configured and you want to employ MSDP Anycast RP, you must disable the PIM Anycast RP before configuring and enabling MSDP Anycast RP.

The following is an example configuration of router A and router B as Anycast RPs in an MSDP domain.

Define a loop back interface as the anycast RP address for each router. In the example, loop.0.8 is used as the anycast RP address.

interface loop.0.8
  ip address 8.8.8.8 255.255.255.255 primary
  no shutdown

Define another loop back interface or VLAN interface to be MSDP peer address. In the example, loop.0.1 is used as the MSDP peer address for both routers.

[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 another loop back interface or VLAN interface to be MSDP peer address. In the example, loop.0.1 is used as the MSDP peer address for both routers.

[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

Configure MSDP peer and originator-ID.

[On router A:]

ip msdp originator-id loop.0.1
 ip msdp peer 122.2.2.2 connect-source loop.0.1

[On router B:]

ip msdp originator-id loop.0.1
 ip msdp peer 121.1.1.1 connect-source loop.0.1

Define an RP address for the whole PIM-SM domain.

ip pim rp-address 8.8.8.8 224.0.0.0 240.0.0.0

Verify that unicast protocols such as OSPF or BGP work. This is necessary for all PIM-SM.