[c-nsp] Sup720, multicast bothers the CPU

[Peter Rathlev]

On Wed, 2011-03-23 at 13:39 -0600, John Neiberger wrote:
> On Wed, Mar 23, 2011 at 8:47 AM, Chris Evans <chrisccnpspam2 at gmail.com> wrote:
> > Peter. Yes just enable igmp snooping and querier.  Easier way is to
> > enable pim which does the rest.  Traffic that has a low ttl of one
> > will still get punted to the CPU..
> 
> Agreed. Just enable PIM. A *,G entry will be created with the Drop
> flag set so that all that traffic will get dropped in hardware.
> However, if you also have an RPF issue, those packets still get punted
> to the CPU, in which case you'll need to turn on mls rate-limiting for
> non-rpf multicast packets.

Thanks. We'll try just adding "ip igmp snooping querier" to the specific
SVI to see if this in itself would be enough. Next up we try "ip pim
sparse-mode" on the SVI and "ip multicast-routing" in global.

I'll keep the list updated on how it went. :-)

-- 
Peter