A coworker brought an interesting problem to me the other day. He wanted to move a serverfarm from one server VLAN to another without taking an outage. Since I didn’t want to have to come into the office late at night to do work, I decided to see what we could do.
It turned out to be pretty easy. We tend to think of CSM VLANs as pairs – you have the client VLAN for the web servers where the vserver sits and the server VLAN where the serverfarm sits. The CSM doesn’t know about these relationships; all it cares about is whether the servers are in a server VLAN, and we can use that to our advantage here.