Netflow on SUP720-3BXL

Sun Mar 15 09:23:29 UTC 2009

On 15/03/2009 01:55, Andy Bierlair wrote:
> I’m trying to run netflow on one of our Cisco core routers (SUP720-3BXL),
> but I think I am hitting some limitations because of this:

Sounds about right for the amount of traffic you're pushing through the 
box.  The SUP720 is a very poor netflow platform.

There has been extensive discussion about this problem in cisco-nsp over 
the past several years, and this posting is probably more appropriate to 
that mailing list.  But basically, there is too little netflow tcam on this 
card to deal with anything more than a couple of gigs of traffic.  You can 
help things by setting the aging timer to be very aggressive, and by 
getting DFCs (although these are a rather expensive option).  Sampling 
won't generally help, as the sampling is done in software, after the data 
has been collected.

More info on:

> http://www.google.com/search?q=sup720+netflow+%2Bsite:puck.nether.net/pipermail/cisco-nsp

Nick