Multicast high cpu

cowetacoit · ‎05-07-2008

My cisco 4506 goes nuts every time i turn multicast on. Unfortunately most of my inherited network is on vlan 1, which i'm slowly segmenting. When ever we need to use a multicast application i have to turn multicast on for vlan 1 (ip pim sparse-mode) When i enable it my cpu stays around 80-100%. When i run a show ip mroute counters there are about 50 routes in it. I guess my question is what can i do about this. I'm sure there are a few different applications that use it but there are all kinds of MC IP's. If i ping one of the IP's, it replays back from a network printer, a proximity panel. is this even reliable?

cisco_lad2004 · ‎05-07-2008

Make sure you do not have igmp static join on any loopbacks.

I had few cases were it caused 60% CPU increase as packers were process switched.

HTH

Sam

cowetacoit · ‎05-08-2008

It isn't. Someone on another forum said to enable IGMP Snooping. i did, and the CPU didn't drop.

cisco_lad2004 · ‎05-08-2008

can u identify any interfaces that are switching a heavy load ?

what does "sh process cpu | exc 0.00" list.

with 4500 you can actually SPAN CPU and find out what is hitting it.

HTH

Sam