Rbd connector fails if cluster_name not set

[Mark Kirkwood]

The rbd connector accepts a cluster_name parameter and then uses it like:

str(cluster_name)

This results in it trying to use a non existent key file:

None.client.<name>.keyring

instead of ceph.client.<name>.keyring, and thus a 'connect to cluster failed' error. This is simply solved by amending os_brick/initiator/connectors/rbd.py (see attached)

[Mark Kirkwood (mark-kirkwood)]

We are running into this issue due to using quite an old version of Cinder (Mitaka), which does not set 'cluster_name" in its connection dict. We are looking at solving this by patching Cinder to include this (Cinder upgrade is TODO).

Having said that - defaulting to a cluster name of 'None' is *never* going to be correct, so the os0brick code behaviour is undesirable.