[c-nsp] Storm-Control on server switch uplinks.

[Peter Rathlev]

On Thu, 2010-09-02 at 16:34 -0400, Jon Lewis wrote:
> cloud-uplink-sw-1#sh int count broad
> 
> Port      BcastSuppDiscards
> Gi0/1                     0
> Gi0/2                     0
> Gi0/3                     0
> ...
> 
> The switch is running the latest code (12.2(55)SE).  All the counters are 
> 0...which makes me wonder if they "work" because the servers on this 
> switch were generating occasional broadcast/multicast storms before the 
> 3560G's were put in place.

FWIW we were recently lucky enough to experience a broadcast storm (no
real ill effects though), and the involved switches actually increased
their counters:

 rhzzz-xfm-asw-106#sh int gi0/28 cou bro
 
 Port      BcastSuppDiscards 
 Gi0/28               358304 
 rhzzz-xfm-asw-106#

I can't assess if the numbers are totally correct, but they do increase.
This one is a WS-C3560G-24PS running 12.2(50)SE3.

Might the servers not just stay below the configured limit?

Measuring IF-MIB::ifInNUcastPkts from e.g. Cacti of course gives you the
counts even when nooen violates the threholds.

-- 
Peter