feature: enable admin socket and log file for librbd client

[dongdong tao]

currently, we don't have admin socket and log file for librbd client.
it would be hard for us to debug if something wrong in librbd client.
we need to enable this on glance, nova-compute, cinder.

[dongdong tao (taodd)]

we can add below two lines to ceph.conf to enable this

log file = /var/log/ceph/$name.$pid.log
admin socket = /var/run/ceph/$name.$pid.asok

[Edward Hope-Morley (hopem)]

glance charm patch - https://review.openstack.org/#/c/594082

[Edward Hope-Morley (hopem)]

Charm-helpers patch - https://github.com/juju/charm-helpers/pull/204

[Trent Lloyd (lathiat)]

For the logfile I proposed a new charm-helpers commit here to enable 'log to syslog' and 'err to stderr' (instead of 'log to file') in ceph.conf to solve the logging issue. Full description at the link.
https://github.com/juju/charm-helpers/pull/608

For the admin socket, it's more complicated, so I will do it separately. Currently /run/ceph is managed by systemd-tmpfiles /usr/lib/tmpfiles.d/ceph.conf and is creates as '0770' ceph:ceph which libvirt/qemu process cannot write to. I think probably this should switch to a world writable tmpdir like /var/log/ceph but am evaluating that change. We could potentially write to an alternative location but then the 'ceph' command wont find it automatically and we need to specify th epath manually. After making that change whatever it is there is also code in the various charms around /var/run/ceph and /run/ceph including charm code that does a chgrp to kvm (that doesn't survive a reboot) that needs cleaning up from old bugs like https://bugs.launchpad.net/charm-cinder-ceph/+bug/1779676. Also on focal /run/ceph exists in apparmor but on bionic it doesn't (see: bug #1779674) and also the charm versions of the apparmor profiles that override the packages versions might need a sync.

[Trent Lloyd (lathiat)]

Also once approved sync to the charms is needed.

[OpenStack Infra (hudson-openstack)]

Change abandoned by "Billy Olsen <email address hidden>" on branch: master
Review: https://review.opendev.org/c/openstack/charm-nova-compute/+/594082
Reason: Patch has not been updated to address feedback in > 180 days.