Comment 2 for bug 1840283

While the error message the ceph tool prints is a bit confusing the tool still does what it should.

I believe the issue here is a change in the bootstrap process [0] and our charms need to be updated to cope with the new workflow.

The smoking gun is this:

2019-08-19 05:29:00 DEBUG mon-relation-changed /usr/sbin/ceph-create-keys: This tool is obsolete; mons now create these keys on their own, and
2019-08-19 05:29:00 DEBUG mon-relation-changed /usr/sbin/ceph-create-keys: this tool does nothing except print this message.
2019-08-19 05:29:00 DEBUG mon-relation-changed /usr/sbin/ceph-create-keys: It will be removed in the next release. Please fix your script/tool.
2019-08-19 05:29:00 INFO juju-log mon:0: Retrying 'add_keyring_to_ceph' 1 more times (delay=15)

Excerpt from Nautilus release notes [0]:
The ceph-create-keys tool is now obsolete. The monitors automatically create these keys on their own. For now the script prints a warning message and exits, but it will be removed in the next release. Note that ceph-create-keys would also write the admin and bootstrap keys to /etc/ceph and /var/lib/ceph, but this script no longer does that. Any deployment tools that relied on this behavior should instead make use of the ceph auth export <entity-name> command for whichever key(s) they need.

0: https://docs.ceph.com/docs/master/releases/nautilus/