Ceph Manager Daemon

The Ceph Manager daemon (ceph-mgr) runs alongside monitor daemons,to provide additional monitoring and interfaces to external monitoringand management systems.

Since the 12.x (luminous) Ceph release, the ceph-mgr daemon is required fornormal operations. The ceph-mgr daemon is an optional component inthe 11.x (kraken) Ceph release.

By default, the manager daemon requires no additional configuration, beyondensuring it is running. If there is no mgr daemon running, you willsee a health warning to that effect, and some of the other informationin the output of ceph status will be missing or stale until a mgr is started.

Use your normal deployment tools, such as ceph-ansible or ceph-deploy, toset up ceph-mgr daemons on each of your mon nodes. It is not mandatoryto place mgr daemons on the same nodes as mons, but it is almost alwayssensible.