Mini HOWTOS.

Create a new blank disk image.

This was so simple I laughed once I got it working. . For example to create a new 8GB disk file use:

You will need the qemu image package:

This can be added to any existing virtual machine as a second drive.

Howto resize a libvirt (kvm/qemu) disk image

Start by creating a new virtual disk. The size of this new disk will be added to the original, it's that simple. Use the command above to create the new disk. I'm told you can also use dd but it is much slower.

Now all you need to do is concatenate the two together, and Linux has the command 'cat' for doing just that. You just have to love Linux.

There "should" be no need to make a backup of the original as it will remain unchanged ( I make a copy anyway). You can then use the bigger.img to add a new partition or simply enlarge the existing ones. Depending on the size of the two files it may take some time and make the real hard disk rattle a bit :-).

If you need to convert the original disk from vdi to raw this is the command it also effectively makes a backup.

To convert the img back to a VDI

The above command will also recompress the unused data making the final vdi file smaller.