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 …
We talked about running multiple data centers on a stick back in August, which is where you have multiple logical pairs of client and server VLANs on a single CSM for different tiers or functions. The …
I must be bored since I’m posting again. A colleague asked me to change the failed value of a TCP probe today. It was no big deal, but, when I looked to see the status of the change, I noticed …
I’ve talked about probes and stuff on the CSM, but I never mentioned what happens to the connections to a server that fails. That is, if I’m connected to server A in a cluster and that …
There are three different ways that a CSM checks for the health of the servers – active probes, inband health checking, and inband HTTP monitoring. Let’s talk about active probes. Active …
Like (nearly) everything in the Cisco world, you can set up your CSM to fail over to another module when the primary dies a horrible death. You can have two in the same chassis or even have them in …
That’s an awesome title, eh? I’ve mentioned a router-on-a-stick before but not a data-center-on-a-stick (DCOAS). This is one of those Cisco terms I ran across a while ago and is a group of …