Antonio Soares <amsoa...@netcabo.pt> wrote: > > I have a customer with a few 3560/3750's and one 4500/SUP5 acting as the > core switch. > > For some reason, when a user start one multicast stream, the 4500 suffers > high cpu utilization and the network is affected. Only the 4500 suffers of > this problem, the 3560/3750's don't have any complaints. > > I see that the 4500 is a CEF based platform and I know that IP Multicast is > not supported in the CEF path. So I was expecting to have this traffic > switched in hardware or fast-switched. But a packet capture shows me that > the traffic goes to the cpu. I used this debug and output to confirm this: > > debug platform packet all receive buffer > > show platform cpu packet buffered > > The processes that eat most of the cpu are "Cat4k Mgmt LoPri" and "Cat4k > Mgmt HiPri". We thought this could be a bug and we upgraded the 4500 to the > latest release but the problem is exactly the same. The multicast stream is > processed by the cpu. > > Anyone has seen this before ? Is this normal behavior of the 4500 ? > > Usually the multicast streams are destined to 224.x.x.x. The end users do > not respect the 239 rule. > > Sounds like the following might help:
http://www.gossamer-threads.com/lists/cisco/nsp/128799?do=post_view_threaded It's the following lines you might need: ---- mls rate-limit multicast ipv4 non-rpf 100 10 mls rate-limit multicast ipv4 partial 250 100 ---- Or something similar to them. Cheers -- Alexander Clouter .sigmonster says: I'm not tense, just terribly, terribly alert! _______________________________________________ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/