CSM load sharing?

[michaell]

My customer is an ISP. They use CSM (content switch module) to do transparent web caching. They have two 6509 switches, each one has a CSM module. Is there any way to distribute the traffic to the two CSMs?

Someone might ask, why not use WCCP v.2? That's because they use CSM to do some URL filtering. And they don't want to overload the cache engines with those filters.

[didyap]

I would suggest that you use MHSRP to distribute traffic to the two CSMs. You could configure the members of one VLAN to use CSM1 as the active and CSM2 as the standby. The members of another VLAN could use CSM2 as active and CSM1 as standby. By doing this you could ensure redundancy as well as distribute traffic to both the CSMs. Hope this helps.

[drizze]

You could also use the RHI feature with the same /32 and inject it into both routing tables statically, then redistribute the /32 into OSPF/EIGRP/ISIS (which in turn puts it back into the routing table as two ECMP entries) or BGP (same effect). You will obviously need 'maximum-paths' configured for the number of ECMP destinations. However, if you are using SUP1/SUP1A, all packets except the first wil be forwarded with MLS, not CEF - so the traffic distribution will not be quite as nice as, say, Sup2 or Sup720 which use CEF/dCEF/aCEF.