If you have the hardware, KVM , or the Kernel Based Virtual Machine has been a pleasure to work with.
I tend to run it from the command line and because I often run servers which do not require X , I was looking for a way of running the guests independent of X.
The solution was in the man pages, simply add the -vnc none and -daemonize options
kvm -hda /media/KVM/Ubuntu.qcow2 -vnc none -daemonize
- -vnc none = initialize the built in VNC server, but do not start a VNC session.
- – daemonize = detach the KVM guest from the host terminal
With these options the KVM guest is now independent of both your terminal, and more important your X session. This means you can log off (or heaven forbid your X session crashes) and your guest server will continue to run in the background.