So let me get started with something useful. I had quite a few problems with VM Server 2.1. As to why I am using VM server, I wanted to locally host a very small, lightweight subversion server, maven nexus repository, and wiki. The wiki ended up dying simply because I couldn't find one that was easy to maintain, or a real reason to use anything more than organized notes on the topics of research I needed to keep up with. I just needed a system for the data I wanted to organize in the wiki, and I ended up just organizing my notes properly, but I digress.
I started with using Ubuntu JEOS operating system, which has a full OS install footprint on VM server of around 500 megs, very nice and compact. I have two of them, statically hosted as "host only" NICs for VM server, meaning my machine can talk to them, but they really can't talk out or be reached to (preventing unwanted hacker attempts and exposing another attack vector into my laptop). Now, these machines are pretty low maintenance, and I simply turn them off before running a backup of my laptop. The problem was that I've had repeated headaches with the new VM Server web access plugins, mainly the console doesn't always work from my browser, both FireFox and IE seem to hiccup from time to time. So, I tried to upgrade from VM 2.1 to VM Server 2.2. What I ended up doing was hosing the install and having to reinstall the VM Server from scratch. When I did this, I ended up changing the subnet for the hosts only virtual NIC.
My insight to the rest of the world, and personal lesson, was that reinstalling VM Server very likely will require you to reconfigure the static IP addresses of machines hosted. Just know it is coming!