VMWare Hardware Recommendations (Windows)
As we increasingly depend on virtual machines to run our autosites, web servers and backups, we are considering combining virtual machines into one physical machine. We are a Windows store and prefer to stay that way (at least in terms of server architecture). If I wanted to host two virtual machines, one of which was running a little-used web server, and one of them used a commonly used build platform (we use Team City, and the virtual machine will be one of the build agents) what hardware would you recommend for physical host machine?
Should I focus on memory? If so, how much? Will more processors differ markedly from performance? Any other thoughts on this matter would be good.
I'm also interested in your experience of hosting multiple virtual machines on one host. How much hosting do you recommend? How many are too many?
source to share
I have been on clients where 100 servers are consolidated to four VM boxes. (Lots of processor cores, 16 or 32 GB of RAM in the field).
VMWare, XEN, etc. really do a great job in the data center. With VMotion and the ability to move a virtual machine from one server in the cluster to another, you no longer need to see hardware downtime.
For your simple case, you could probably use the larger of the two existing boxes you already have, the maximum RAM for what the system will support and do fine.
Realistically, if you get a 4-core box with a spare socket, if you need to add higher performance later and as much RAM as you can afford (draw enough RAM for each server and then a few extras) you should be it's good to go with two servers and also be able to run a test VM for development and testing as needed.
As noted in a later answer, partitioning a disk is a great idea. In large sites, direct SAN connections to the VM server are critical. In the example of this particular question, this is a scale that is out of the question. (SAN for two servers? Come on!) But definitely try to get so many physical spindles in there and dedicated to boxes that need disk performance.
source to share
Your virtual host hardware should be the sum of your current usage plus ~ 10% for overhead (numbers in balls).
If you barely touch one server, it might get away with one processor with 1 gig of RAM, perhaps.
A heavier server that currently has 4 CPUs and 8GB of RAM should have the same purpose when virtualizing - the math is actually pretty straightforward :)
source to share