There may be problems with kvm kernel modules not being loaded. There should be two modules loaded, kvm and either kvm-intel or kvm-amd. If you don't know the processor type, and load status just look at the contents of /proc/cpuinfo and output of lsmod, e.g. by using
Code:
less /proc/cpuinfo
lsmod | grep 'kvm'
If there are no kvm modules loaded, use modprobe to insert them, in the Intel case:
Code:
sudo modprobe kvm && modprobe kvm-intel
A useful feature of kvm is that it can be used to run different OSes installed on the computer in a VM. This can be handy for lots of uses. Using GRUB, this command will give me GRUB's boot menu in a window:
Code:
sudo kvm -hda /dev/sda -m 1024 &
And from the boot screen, pick the OS version to boot. If you are running 32 bits kernel, 64 bits OS versions of course won't work.
The problem can be if different installs mount the same partitions rw, and insist on writing to them. But running Knoppix from a separate partition from what you are using can work just fine. You can do all kinds of administrative work in such a window, I even ran a DVD remastering there once. (The objection that DVD remastering takes a lot of time - if it turns out to be correct - becomes kind of moot when you can du it as a background process in a VM.)