Document virtual image conversion to Azure compatibility

What would you like to see added?

Azure expects images to be in a fixed-size VHD format. OpenStack cannot export to this format on its own, but with the help of the bundled qemu-img software, images can be converted.

The process involves creating an image from an instance, saving it to a local device, converting it to the appropriate format, and then uploading it to the Azure service. Here we document all but the last step. Note that these three steps can be performed within an instance on OpenStack (but not within the instance being imaged). They do not need to be performed on your local machine.

openstack image create --disk-format==raw --id=$myid
openstack image save --file=myimage.raw $myid
qemu-img convert -f raw -O vpc -o subformat=fixed,force_size myimage.raw myimage.vhd

Note these commands are not final, they need to be double-checked. I wanted to write this down before I forgot about the concept entirely.

Note also that the Azure portion of the process is handled by Client Services in Enterprise IT.