CSM Server LB across L3 Devices

[stevelaffan]

I have a pair of 6513's with a CSM in each. These are port-channelled together to provide FT.

I have a number of server vlan's defined on the 6500 and 2 of these need to be LB through the CSM.

Do I define these servers as CSM server vlans (which I have now done) or define the servers as 6500 server vlans with L3 interfaces defined on the 6500's and add route commands to the CSM server VLAN's to route back to these servers via the 6500 L3. I am concerned on this last point about Nat requirements for client connections and how to guage the number of nat pool addresses I need.

My reason for this question is that I am having trouble getting ping access to these LB servers through the CSM even though I have defined server farms with a predictor of forward. Cisco give information on forwarding using TCP / UDP but give no indication of whether the CSM predictor forward supports ICMP.

[Gilles Dufour]

predictor forward support icmp.

The servers can be in a vlan attached to the csm or the msfc, it does not matter.

From where to where do you have problem to ping ?

Is it only a ping issue or is there other protocols not working ?

What is the config ?

Gilles.

[stevelaffan]

I am having trouble pinging from an interface on the sup720 / switch fabric on a different subnet to a server on a vlan defined in the CSM as a server vlan.

Not seeing any hits on the csm for this serverfarm.

You said the servers can be on either the CSM or MSFC, but if put the servers to be load balanced on the MSFC, I will need to put in client Nat on the serverfarm to ensure the real server does not attempt to reply directly back to the requestee. If this is the case, does the CSS use a 1 to 1 Nat relationship or does it essentially do a many to 1 address (PAT)