KVM snapshot backups with qemu-img

I noticed that a new feature had been added to qemu-img which allowed for copying a snapshot out of a qcow2 image to become it’s own qcow2 image.  This would allow me to make live snapshots of my running KVM instances and archive them off to another machine.  I got around to testing it this morning and it appears to work fine, streaming back “Big Buck Bunny” whilst archiving off my test machine resulted in only a couple of slight (0.5 sec maybe) pauses.

I’ve produced a small script which allows me to make a backup of the current image, it’s available here, note since I’ve had to compile head of qemu-img I’ve chosen not to overwrite my Lucid version, and have instead called it qemu-img2.