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Multicast RP confusing


I have a 65xx (Sup1A, MSFC2) and a 26xx .

Both routers are configured as RP-CANDIDATE , the 65xx being also BSR-CANDIDATE. Each router sees the other as RP .

As far as I understand, the RP should be uniquely elected through the whole domain, as it is choosen by the BSR and propagated to all the other pim sparse multicast routers .

Did any of you notice this type of behaviour.

The versions I'm running are as follows:

MSFC IOS 12.1(8b)E11

26xx IOS 12.0.7T

Igmp snooping enabled at CatOs level

Interfaces on routers configured with pim sparse-mode

on 65xx : ip pim bsr-candidate loopback 0 0

ip pim rp-candidate loopback 0

on 26xx: ip pim rp-candidate loopback 0

The messages I get on both consoles are:

%PIM-6-INVALID_RP_JOIN: Received (*, Join from for invalid RP ( 26 on the 2nd one)


Re: Multicast RP confusing

If you receive the error message mentioned by you,it indicates that

A downstream PIM router has sent a join message for the shared tree, which this router does not want to accept. This behavior indicates that this router will let only downstream routers join to a specific rendezvous point.

The workaround is to Configure all downstream leaf routers (first-hop routers to multicast sources) to join to the RP that is allowed by upstream routers toward the validated rendezvous point.

Please let me know if this works. You could also refer to the IP Multicast Troubleshooting Guide:

Check the following doc.

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