Comment 5 for bug 1671422

Resolution of this in the charms might look something like this:

1) addition of new relation between cinder-ceph and nova-compute

cinder-ceph will need to provide its cephx key + UUID that it will use in its configuration files for this purpose; this cannot be fixed (as in nova-compute) as its possible multiple backends will be in use, so the UUID must be specific to the backend (so some complexity in HA deployments with regards to which unit will generate the UUID and how the other units will observe and consume the UUID - via leader storage).

2) updates to nova-compute

consumption of the new interface, storage of secret in libvirt using the UUID provided from the cinder-ceph charm.

I'm still not hugely keen on having the compute units share keys with the cinder-ceph units.