Because we are a Church, we are considerably more cost conscious than a typical enterprise would be. In an effort to save power, cooling & hardware costs in our data center, we've begun implementing virtualization. We've been using virtualization for quite some time with our AIX servers, but we've now begun to virtualize Windows and Linux boxes.
Most of you know what virtualization is, but for those who don't, I'll try to explain.
<virtualization_explanation>
In the past, when a team needed a server in the data center, we would purchase them their own server. Their application might use, on average, 10% of the capabilities of that server. Or less. It was a waste, not just for our shop, but for the entire industry. A potential, but not always viable, solution was to load multiple solutions onto one box, but those solutions shared the application server and operating system and consequently could interfere with each other by crashing the operating system or the application server and/or just utilizing too much of the computer's brain (CPU).
Virtualization allows us to load multiple instances of an operating system on a single box. So on one machine, we could load several solutions, each with its own instance of the application server (Websphere) and the operating system (typically Linux). So if one solution crashes its instance of the OS, the other solution is just fine because it's running on top of its own instance of the OS.
And because each solution was previously only using around 10% of the total resources of the server, you can run, say, 5 solutions on one server and still only use around 50% of the server's resources. You just cut your power, cooling and hardware costs by roughly 80% (minus a little overhead for the virtualization technology itself).
Pretty amazing.
</virtualization_explanation>
We have seen significant, and maybe even extraordinary, savings on our "per server" costs as a result of virtualization.
The unintended consequence has been "server sprawl." The ease, speed and extremely low cost of creating a new server (because it is virtual) has increased the demand for servers. Without great governance and management tools, this is becoming a problem for most enterprises.
How are you dealing with "server sprawl" in your shops?