Ceph » mgr

Since Mimic, ceph-mgr module configuration is stored in the same central config store on the mons as the rest of Ceph config.

That should make it possible to load the config from ceph.conf too -- I haven't tried this and suspect it might need some tweaks to get it working, but it's probably worth the effort in order to be consistent with the other config options.

If it's easier, I would probably be okay with making this only take options from the ceph.conf on the monitor. There's a reasonable use case for file-based config (writing all the config before starting the cluster), but there's (probably) no really good case for people to configure their mgr modules by writing out to /etc on local mgr nodes.