devstack-plugin-ceph-tempest job failing with "ERROR cinder ImportError: Class ceph cannot be found"

[melanie witt]

Recently, cinder dropped legacy backup service support in this change:

https://review.openstack.org/595372

and no longer allows module names to be specified for the backup_driver config option -- the option must use a full class name.

The devstack-plugin-ceph-tempest job is currently failing with "ERROR cinder ImportError: Class ceph cannot be found":

http://logs.openstack.org/97/604397/6/check/devstack-plugin-ceph-tempest/7f846fa/job-output.txt.gz#_2018-09-26_10_44_37_805286

so it looks like we need to update backup_driver from "cinder.backup.drivers.ceph" to "cinder.backup.drivers.ceph.CephBackupDriver" to get things working again.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/605833

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/605833
Committed: https://git.openstack.org/cgit/openstack-dev/devstack/commit/?id=991b1f13f0aed578dccec2e761be69005357444f
Submitter: Zuul
Branch: master

commit 991b1f13f0aed578dccec2e761be69005357444f
Author: melanie witt <email address hidden>
Date: Thu Sep 27 18:30:38 2018 +0000

    Update cinder backup_driver to full class name

    Legacy backup service support was recently dropped from cinder in
    change I3ada2dee1857074746b1893b82dd5f6641c6e579 and we need to
    adjust how we set the config option in devstack accordingly. This
    updates the backup_driver option to specify a full class name instead
    of only the module name.

    Closes-Bug: #1794859

    Change-Id: I3a72f38b564b8b83b233fccba7685833b6394d45