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

[Lincoln Dale (ltd)]

g'day Steven,

I'll preface this by saying its cool to see that someone is finally
writing proper hash-mask support for squid.  BUT, I'll preface all of
this by saying that _IF_ you NEED hash-mask (because of alternate
methods on cat6k/7600 cause too much traffic out of h/w-switched paths
on the switch/router), then its very very very unlikely that Squid will
cut it for you.
put simply, unless something significant has changed in the last couple
of years, squid just ain't made for high performance.

> I've seen some posts on this list regarding getting wccpv2 working
with a
> cisco 7600 using L2 redirect assignment.  I'm trying to get this
working
> under squid, and I believe I've got it correct according to the draft
> wccp2 RFC that was published around 2000/2001.  My problem is that the
> cisco router reports the following error while the WCCP negotiation is
> ocurring:
> 
> 3d21h: WCCP-EVNT:wccp_validate_wc_assignments: no mask data, exit
> 
> The problem is that this is in response to a HERE_I_AM packet.

the router is indicating that it isn't seeing any valid cache
assignments in the mask data.

the key point here is that if you think you've set everything correctly,
the router is saying otherwise.

perhaps if you can post/link to the code fragment you're using to build
the hash-mask-assignment packet?

> Has anyone got a working wccp2 implementation that negotiates L2
redirects
> and mask assignments that I can use as a reference for squid?  The
other
> option for me would be to get a packet dump of the wccp2 negotiation
> packets so I can look at what parts of the packet I'm missing.

as far as I know, only Cisco caching/content products only ever
effectively made use of hash-mask method.  how about you post the output
of the packets you're generating & we can look at it from this side?



cheers,

lincoln.