[c-nsp] WCCPv2 Cisco 7600 + mask assignment problems

[Lincoln Dale (ltd)]

> What's the best real world performance seen on a 7600/6500 with WCCP ?

as I say, it all "depends" on what 'mode' of WCCP you make use of:
 - using L2 rewrite rather than GRE encap to the cache scales more.
 - L2 + XOR traffic-distribution-hash uses MLS cache entries for
   partial h/w acceleration (1st flow in s/w sets up MLS entry)
   for intercepted flows.
 - L2 + "hash-mask" traffic-distribution means _all_ traffic stays in 
   h/w CEF path

the former will get you up to a few hundred Mbps, the latter will scale
to the maximum h/w forwarding of the platform.  (cat6k/7600 can do the
latter even without any need for 'packet recirculation').

what does your cache vendor support?  they should support all
permutations & if you used the latter, it'll scale to the limits of the
h/w.

> We moved away from 6500+Sup2+WCCP when we hit TCAM issues.

if you were using the latter, even Sup2 would have been just fine.


cheers,

lincoln.