Migrate from RAW to QCOW2

Community Support Storage
1

Hello everyone,
I use a Ceph datastore as an image repository. The system datastore is localhost and by using TM_MAD as ssh everything is working great. I want to change VM image format from RAW to qcow2 due to the use of incremental backup. In VM template I add DRIVER=qcow2 but it’s still create RAW format (I checked by qemu-img info).

DISK = [
  DEV_PREFIX = "vd",
  DRIVER = "qcow2",
  IMAGE = "Debian 11",]

What should I change more? RBD uses RAW disk, maybe it’s impossible to convert it to qcow2?

1 Like
2

Hello,

Actually yes, RBD uses RAW disk format, when the VM is deployed it is automatically converted.
The snapshots made in RBD images (for incremental backups) are Ceph-based.

Did you have any problem defining a incremental backup job with a ceph based image?

https://docs.opennebula.io/6.8/management_and_operations/backups/backup_jobs.html

3

Hello Bruno
Thank you for your answer. I resolved this problem by creating a new Datastore with qcow2 OS images.
Anyway live incremental backup is not working. When I turned off VM, backup was done. I get the below error:

Error: Error executing ‘virsh --connect qemu:///system backup-begin --reuse-external --backupxml /var/lib/one//datastores/167/814/tmp/backup.xml --checkpointxml /var/lib/one//datastores/167/814/tmp/checkpoint.xml 48b71aba-6b4c-45f4-ba1f-443361995077’: error: Operation not supported: creating checkpoint for incremental backup is not supported yet

libvirtd 8.0.0
qemu 5.2.0
opennebula 6.8.0