Backing up your VM: Difference between revisions

As with creating backups of persistent VMs, the main goal is to create an image of at least the root drive, and perhaps also other attached volumes if needed. However, differences with compute flavor VMs change the process of creating that image. Compute VMs are not designed to boot from volumes accessed over the network as persistent VMs are, instead they are meant to be booted from disk images which reside locally on the computer which is actually running your VM. This means there is no volume which you can click on in the OpenStack dashboard to create an image of your root disk. Instead you can do this by clicking "Create Snapshot" on your VM's drop down menu on the "Instances" tab. As with creating a snapshot with a persistent VM this creates an image. However, in this case the image is not nearly empty containing only pointers to volume snapshots. Instead the image contains a copy of the VMs root drive.

Compute VMs also come with an extra data drive mounted at <code>/mnt</code>, the data on this drive is not captured in the image created of a compute VM. Other arrangements must be made to save this data, such as coping it off the disk before the VM is terminated.