Exception seen in cinder-volume.log when unmanaging a volume

 Environment has ceph as a storage backend

The following exception could be seen in cinder-volume.log:

0fdc2108b78c63 29a3255438bc49e7895968ff67c14682 - - -] Exception during message handling: 'RBDDriver' object has no attribute 'unmanage'
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher Traceback (most recent call last):
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/dist-packages/oslo_messaging/rpc/dispatcher.py", line 142, in _dispatch_and_reply
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher executor_callback))
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/dist-packages/oslo_messaging/rpc/dispatcher.py", line 186, in _dispatch
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher executor_callback)
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/dist-packages/oslo_messaging/rpc/dispatcher.py", line 129, in _do_dispatch
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher result = func(ctxt, **new_args)
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/dist-packages/osprofiler/profiler.py", line 105, in wrapper
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher return f(*args, **kwargs)
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/dist-packages/cinder/volume/manager.py", line 146, in lvo_inner1
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher return lvo_inner2(inst, context, volume_id, **kwargs)
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/dist-packages/oslo_concurrency/lockutils.py", line 254, in inner
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher return f(*args, **kwargs)
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/dist-packages/cinder/volume/manager.py", line 145, in lvo_inner2
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher return f(*_args, **_kwargs)
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/dist-packages/cinder/volume/manager.py", line 643, in delete_volume
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher 'error_deleting')
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/dist-packages/oslo_utils/excutils.py", line 195, in exit
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher six.reraise(self.type_, self.value, self.tb)
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/dist-packages/cinder/volume/manager.py", line 627, in delete_volume
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher self.driver.unmanage(volume_ref)
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher AttributeError: 'RBDDriver' object has no attribute 'unmanage'
2016-02-17 13:59:29.068 4925 ERROR oslo_messaging.rpc.dispatcher

VERSION:
  feature_groups:
    - mirantis
  production: "docker"
  release: "8.0"
  api: "1.0"
  build_number: "569"
  build_id: "569"
  fuel-nailgun_sha: "558ca91a854cf29e395940c232911ffb851899c1"
  python-fuelclient_sha: "4f234669cfe88a9406f4e438b1e1f74f1ef484a5"
  fuel-agent_sha: "658be72c4b42d3e1436b86ac4567ab914bfb451b"
  fuel-nailgun-agent_sha: "b2bb466fd5bd92da614cdbd819d6999c510ebfb1"
  astute_sha: "b81577a5b7857c4be8748492bae1dec2fa89b446"
  fuel-library_sha: "33634ec27be77ecfb0b56b7e07497ad86d1fdcd3"
  fuel-ostf_sha: "3bc76a63a9e7d195ff34eadc29552f4235fa6c52"
  fuel-mirror_sha: "fb45b80d7bee5899d931f926e5c9512e2b442749"
  fuelmenu_sha: "78ffc73065a9674b707c081d128cb7eea611474f"
  shotgun_sha: "63645dea384a37dde5c01d4f8905566978e5d906"
  network-checker_sha: "a43cf96cd9532f10794dce736350bf5bed350e9d"
  fuel-upgrade_sha: "616a7490ec7199f69759e97e42f9b97dfc87e85b"
  fuelmain_sha: "d605bcbabf315382d56d0ce8143458be67c53434"