Swapping out servers on in a dual CSM configuration

[r.catallo]

I have a dual 6506/CSM configuration with a couple of server farms that I will swapping out the backend (serverfarm) servers. Real IP addresses of the servers won't change, but obviously the MAC addresses associated with each will. Question: how to swap, will MAC-ADDRESS cam table change update the CSM ARP-CACHE? Will I need to manually clear the CSM ARP-CACHE and/or MSFC's ARP CACHE.

[Gilles Dufour · Accepted solution]

The CSM arp cache for real server is 5 minutes. It's configurable with the variable :

ARP_INTERVAL 300

So, withing 5 minutes the CSM should detect the new mac. You can force the arp refresh by doing a 'clear mod csm X arp x.x.x.x'.

Do not clear the full arp table as this would impact current connections.

Gilles.

[r.catallo]

Thanks Gilles for your quick response.

Ron Catallo

NPC