This Dockerfile creates a Ceph metadata server (MDS) image
The environment variable MDS_NAME is required. It describes the name of the MDS
For example:
docker run -e MDS_NAME=mymds ceph/mds
It will look for either /etc/ceph/ceph.client.admin.keyring or /etc/ceph/ceph.mds.keyring with which to authenticate. You can get ceph.client.admin.keyring from another ceph node.
Commonly, you will want to bind-mount your host's /etc/ceph into the container. For example:
docker run -e MDS_NAME=mymds -v /etc/ceph:/etc/ceph ceph/mds
Note: ceph-mds seems to die most of the time when trying to start it. Trying repeatedly will eventually get it to run. If run manually within the container (enrtypoint to base, then manually run entrypoint.sh), it fails less often, but still frequently (though less than 50% of the time).