Ceph » CephFS

Due to the removal of the 'ceph mds dump' command in nautilus, a luminous ceph_volume_client does not work against a nautilus cluster. This breaks some version combinations of openstack cloud and ceph.

Here's a log fragment of manila:

2019-05-23 09:56:50.763 INFO manila.share.drivers.cephfs.driver [req-34c1c009-cf00-48e8-ab3a-e19ea4bc8df8 None None] [CEPHFSNATIVE1}] Ceph client found, connecting...
2019-05-23 09:56:50.802 INFO ceph_volume_client [req-34c1c009-cf00-48e8-ab3a-e19ea4bc8df8 None None] evict clients with auth_name=manila
2019-05-23 09:56:50.872 ERROR manila.share.manager [req-34c1c009-cf00-48e8-ab3a-e19ea4bc8df8 None None] Error encountered during initialization of driver CephFSDriver@192.168.24.218@cephfsnative1: Error: command is obsolete; please check usage and/or man page
2019-05-23 09:56:50.872 TRACE manila.share.manager Traceback (most recent call last):
2019-05-23 09:56:50.872 TRACE manila.share.manager   File "/usr/lib/python2.7/site-packages/manila/share/manager.py", line 305, in _driver_setup
2019-05-23 09:56:50.872 TRACE manila.share.manager     self.driver.do_setup(ctxt)
2019-05-23 09:56:50.872 TRACE manila.share.manager   File "/usr/lib/python2.7/site-packages/manila/share/drivers/cephfs/driver.py", line 144, in do_setup
2019-05-23 09:56:50.872 TRACE manila.share.manager     ceph_vol_client=self.volume_client)
2019-05-23 09:56:50.872 TRACE manila.share.manager   File "/usr/lib/python2.7/site-packages/manila/share/drivers/cephfs/driver.py", line 216, in volume_client
2019-05-23 09:56:50.872 TRACE manila.share.manager     self._volume_client.connect(premount_evict=premount_evict)
2019-05-23 09:56:50.872 TRACE manila.share.manager   File "/usr/lib/python2.7/site-packages/ceph_volume_client.py", line 474, in connect
2019-05-23 09:56:50.872 TRACE manila.share.manager     self.evict(premount_evict)
2019-05-23 09:56:50.872 TRACE manila.share.manager   File "/usr/lib/python2.7/site-packages/ceph_volume_client.py", line 399, in evict
2019-05-23 09:56:50.872 TRACE manila.share.manager     mds_map = self._rados_command("mds dump", {})
2019-05-23 09:56:50.872 TRACE manila.share.manager   File "/usr/lib/python2.7/site-packages/ceph_volume_client.py", line 1340, in _rados_command
2019-05-23 09:56:50.872 TRACE manila.share.manager     raise rados.Error(outs)
2019-05-23 09:56:50.872 TRACE manila.share.manager Error: command is obsolete; please check usage and/or man page

https://github.com/ceph/ceph/compare/luminous...jan--f:ceph_volume_client-version-aware implements a potential fix.
Another option would be to simply replace the 'mds dump' calls with 'fs dump', since the latter is present in luminous. Not sure if that breaks something else though.