No MSDP SA?

[KGrev]

Hi,

We are setting up msdp peering between two RP's.

We have yet to get it fully functioning but when we do "show ip msdp summary" or "show ip msdp peer",  there is a "?" for the SA.

We do get logs that the peer is up.

The commend we are using is

Router A = "ip msdp peer "routerB" connect-source loopback1"

Router B = "ip msdp peer "routerA" connect-source loopback1"

Our peer is up but we are not sharing multicast groups yet.

Thank you for any advice.

[Harold Ritter]

@KGrev ,

The issue you are seeing between router A and router B is definitely due to the fact that router A is configured as with the following command "ip pim rp-address 10.224.A.B bidir". To make it work you need to remove the "bidir" keyword.

You probably need to review your design to integrate router C in the MSDP design.

Regards,

[KGrev]

@Harold Ritter 

I'm still learning this. Can you explain the effect bidir is having on this setup?

Also, do you suspect that if we brought things down to a less complicated level, would each router only have its own rp statement for its loopback and the required msdp statements to peer with the other two routers? Would router B be able to peer to router C or would Router A transfer messages between C and B?

[Harold Ritter]

@KGrev ,

> I'm still learning this. Can you explain the effect bidir is having on this setup?

PIM bidir doesn't use of the multicast source. So, it will not send PIM (S,G) joins towards the multicast source even though it receives the source information via MSDP. It rather sends PIM (,G) joins towards a virtual RP. In that sense, there is an incompatibility between using PIM bidir in conjunction with MSDP.

> Also, do you suspect that if we brought things down to a less complicated level, would each router only have its own rp statement > for its loopback and the required msdp statements to peer with the other two routers? Would router B be able to peer to router C

> or would Router A transfer messages between C and B?

A very simple and redundant design would be to have two RPs configured as Anycast RP and have a static RP with the anycast address configured on all other devices.

Regards,

[KGrev]

@Harold Ritter 

Thank you very much for your help. We'll have some network downtime in a few days. Ill try to use that time to implement this change and get back with you on the outcome.