Sadagopan points out this Infoworld article,
Virtualisation and Reality which discusses the growing acceptance of Virtual Servers.
Server Virtualisation is very cool stuff, allowing you to run one or several "virtual" stand alone servers within a normal OS environment. To your network, they actually do look like several unique machines, although they all run on your desktop, or server depending on which product you buy. The first time people see it and use it, it comes as a bit of a revelation how useful it can be. For geeks that like to dabble (a group most DBAs are probably part of) it can be a sandbox to try new ideas or programs, comletely fenced off and safe from your normal OS. The products (from
VMWare and Microsoft (
Virtual PC) almost exclusively) allow you to mount iso images, so you can do cool stuff like download and spin up and check out
cool Knoppix images that you'd never mess with otherwise, because doing so used to require a seperate machine. I have posted links before to instructions on
setting up RAC and an
active-active cluster in VM sessions.
Among our clients, which include Fortune 500 companies and midsize, only two have bought in to Virtualization in a big way. One is a hospital holding company (all of a hospital's apps run on a single server, and when a new hospital is added, the machine's are simply duplicated. An entire environment set up in a matter of hours, and completely configured and ready to go), the other is one of the major car manufacturers Alabama facilities, who does it for the normal reasons, namely utilizing hardware more efficiently.
There are some undeniable advantages, such as backing up or duplicating a virtual machine is as easy as zipping up the files (the entire virtual machine, hd, memory, everything is in files) and copying them off. There's also some disadvantages, such as if the host OS goes, all the virtual mchines go with it. There are some failover features in the server products, but I have heard they are buggy. And then there are licensing wrinkles that come in to play. Microsoft is experimenting not charging for virtual instances if your company has a certain agreement in place, but only if you use Virtual PC, of course.
It's still something that you'll see soon if you haven't yet.