RP Multicast error in switch log

[djs151515]

We keep receiving the below error in the switch log regarding multicast. We have auto rp discovery configured. Not sure why the switch is not finding the correct RP. This is happening on a feeww of our 6500 switches. Any help would be greatly aprpeciated. Thanks 

%PIM-6-INVALID_RP_JOIN: Received (*, xxx.xx.xx.xx) Join from 0.0.0.0 for invalid RP xx.xxx.xx.xx  

Switch configuration for RP:

ip pim spt-threshold infinity
ip pim send-rp-announce Loopback0 scope 16
ip pim send-rp-discovery scope 16

[Peter Paluch]

Hi,

This message basically says that your 6500 received a PIM Join message that is supposed to be directed toward the RP address xx.xxx.xx.xx but this particular 6500 does not know that x.xxx.xx.xx is a RP (it does not consider it to be a RP).

The fact that the source IP address is 0.0.0.0 suggests that this PIM Join was originated by the 6500 itself. The question is whether this xx.xxx.xx.xx is this 6500's own IP address, or whether it is an address of a different device. Before I can suggest a hypothesis, I would need to know about this.

Please note that with AutoRP you're currently using, you either need to configure ip pim autorp-listener on all routers/multilayer switches, or you need to configure all interfaces with ip pim sparse-dense-mode because AutoRP requires dense mode flooding. Have you taken care of that in your network?

Best regards,
Peter

[djs151515]

You are correct the IP address in the log is the 6500s own IP address. 

We do configure  ip pim sparse-dense mode on interfaces that utilize multicast but not all interfaces. Do you suggest adding the ip pim autorp-listener on all switches? Thanks again 

[Peter Paluch]

Hello,

It seems that your ip pim send-rp-discovery command is lacking the interface name whose IP address is used to source the AutoRP group-to-RP mappings. Please try entering the following commands on your 6500 switch from which you have posted the configuration above:

no ip pim send-rp-discovery scope 16
ip pim send-rp-discovery Loopback0 scope 16

I am actually surprised that the command was accepted without the interface name - the IOS CLI quirks never cease to amaze me.

Best regards,
Peter

[djs151515]

Should I add the below line to all our 6500 switches ? Thanks 

ip pim send-rp-discovery Loopback0 scope 16

[Peter Paluch]

Hi,

Should I add the below line to all our 6500 switches?

No, certainly not. Add it only to the switch that is currently acting as the AutoRP mapping agent (the one that was configured with the ip pim send-rp-discovery scope 16 command without referring to the interface name).

I hope you do not have all your switches configured with this command - that would not be correct. It is sufficient to have this command on a single router/switch; you can place it on two different switches to provide redundancy for the mapping agent functionality in the AutoRP, but this command is not intended to be entered on all devices in your network.

Best regards,
Peter