PIM-SM neighbor go down and not coming up

alex-shpil · ‎07-22-2012

Hi,

I have 2 ASR routers running PIM-SM between them on several sub interfaces.

PIM hello interval configured for 200ms.

Sometimes PIM neighbors between ASR routers going down.

Reboot for each router not resolving the problem.

Deleting ip pim sparse-mode and configuring it again on one of the ASR routers resolves the problem.

I didn't find any related bug.

The version is asr1000rp1-adventerprisek9.03.06.01.S.152-2.S1.bin

Anyone has an idea ?

Georg Pauwen · ‎07-22-2012

Hello Alex,

I don't know how much multicast traffic is sent across your network, but by default, the mroutes expire after 180 seconds. You might want to use the 'ip pim-sparse sg expiry-timer' command to increase that value.

Obviously, since I have not seen the configuration of your routers, this is just a wild guess. Can you post the configs ?

Regards,

Georg

Marcel Zehnder · ‎07-23-2012

Hello Alex

I had similar issues with PIM in combination with BFD. Do you use BFD?

Regards

Marcel

alex-shpil · ‎07-23-2012

Hi Marcel,

Yes I'm using BFD.

How did you resolve it ? Or just removed BFD ?

BR,

Marcel Zehnder · ‎07-23-2012

I had to adjust the BFD timers - if they are to aggressiv PIM flaps. And also have a look at the BFD configuration for subinterfaces, there is a command like "bfd optimize subinterface" which is also a good thing to enable (check out the config guide for detail explanation)

HTH

alex-shpil · ‎07-23-2012

But in my case the PIM not flaps.

It goes down and not coming up until I disable and enable it.

Marcel Zehnder · ‎07-23-2012

Yes, but it's something like flapping ;-)

I would suggest the following action plan: Disable BFD on one of your PIM-links. If your PIM-neighborship remains up, there is somenting wrong with BFD. If it goes still down, the issue is something else.