Last week, I started a virtual machine for the first time. Virtual machines are a technology whereby one large, expensive, powerful computer can pretend to be many smaller, less powerful computers instead. This way, all the expensive redundancies can be implemented in the one powerful computer, automation can be increased, and so on. (For instance, a massive RAID array would be expensive to build in a large network of computers, but one more massive array can be built in the main machine that then pretends to be that large network of computers, and then all the virtual machines get all the RAID benefits.) I consider this essential to my future career, as I understand that this is one of all the rages at the moment. (The others being things like drivers and iPhone apps, which I don't have the money to fully investigate.)
I used Xen, an open source virtualization system. Xen requires a special kernel that comprehends virtualization ideas. (Most have no reason to, and so don't.) Every attempt to build one for myself failed, and on my success I was booted from a livecd. My next step will be to boot off my own hard drive instead.
The server that I ran was to be a dns server, which I set up ahead of time, and it operated admirably. I also have a "buildhost" whose job is to compile and distribute software, but I didn't test that one.
Other virtualization options include VMServer, Qemu, LilyVM, OracleVM, and Parallels.
To my readers, I ask, "What specialty computers would you like to see?" I can make webservers, caching hosts, and nearly anything I can setup on a pc. (Although with virtualized machines, you do not get a keyboard, mouse, or monitor, so "Quake computer" is out. A game server is possible, though.)
Also in computer science news, my previous project has been rendered completely obsolete by the people at the linux kernel project who have multiple bootable images, suitable for all kinds of installs, therefore preempting anything I could have put together. Nice.