Acceptance test loopback mount qcow

[Metallion]

Problem

Currently the acceptance test environment is making .raw images and then converting them to .qcow. The reasoning behind this is that .raw is easy to loopback mount and .qcow has copy-on-write.

However, if we could work with .qcow from the beginning, there would be no need for the conversion that does take up some time.

Solution

It looks like nowadays loopback mounting .qcow isn't as hard as it used to be.

From http://ask.xmodulo.com/mount-qcow2-disk-image-linux.html:

sudo modprobe nbd max_part=8
sudo qemu-nbd --connect=/dev/nbd0 /path/to/qcow2/image

Example

sudo qemu-nbd --connect=/dev/nbd0 /var/lib/libvirt/images/xenserver.qcow2
sudo fdisk /dev/nbd0 -l # <= check existing partitions
sudo mount /dev/nbd0p1 /mnt