Ceph backup driver could not restore a volume other than ceph

[Sofia Enriquez]

Steps to Reproduce:
   1. Setup the cinder backup driver to 'cinder.backup.drivers.ceph.CephBackupDriver'

      backup_driver=cinder.backup.drivers.ceph.CephBackupDriver

   2. Create 'LVM' volume.

     $ cinder create --volume-type lvm --name "lvm_vol" 1

   3. Create backup from 'LVM' volume.

     $ cinder backup-create lvm_vol --name "backup_from_lvm_vol"

   4. Create 'LVM' volume to restore the backup.

     $ cinder create --volume-type lvm --name "restore_backup_lvm" 1

   5. Restore from the backup to 4) volume.

     $ cinder backup-restore backup_from_lvm_vol --volume restore_backup_lvm

Actual results:
   Restoring from backup failed

Expected results:
   Restoring from backup success.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/750782

[Sofia Enriquez (lsofia-enriquez)]

Currently the Ceph Backend fails when restoring non-ceph volumes. This happens because the current code is generating the wrong base image when performing a full restore. If we are not using a RBD destination volume we need to specify the backup in the same way than If a source snapshot is provided.In order to locale the right base image used for the backup It should use  backup.service_metadata.

[OpenStack Infra (hudson-openstack)]

Change abandoned by "Sofia Enriquez <email address hidden>" on branch: master
Review: https://review.opendev.org/c/openstack/cinder/+/750782
Reason: I have decided not to continue with the refactor of the Ceph backup driver for this bug. Instead, I am currently working on the bug mentioned in https://review.opendev.org/c/openstack/cinder/+/880965, and I plan to follow up with a refactor/cleaning of the code for this driver in another patch.