=========== MDS Service

.. _orchestrator-cli-cephfs:

Deploy CephFS

One or more MDS daemons are required to use the :term:CephFS file system. These are created automatically if the newer ceph fs volume interface is used to create a new file system. For more information, see :ref:fs-volumes-and-subvolumes.

For example:

.. prompt:: bash #

ceph fs volume create <fs_name> --placement="<placement spec>"

where fs_name is the name of the CephFS and placement is a :ref:orchestrator-cli-placement-spec. For example, to place MDS daemons for the new foo volume on hosts labeled with mds:

.. prompt:: bash #

ceph fs volume create foo --placement="label:mds"

You can also update the placement after-the-fact via:

.. prompt:: bash #

ceph orch apply mds foo 'mds-[012]'

For manually deploying MDS daemons, use this specification:

.. code-block:: yaml

service_type: mds
service_id: fs_name
placement:
  count: 3
  label: mds

The specification can then be applied using:

.. prompt:: bash #

ceph orch apply -i mds.yaml

See :ref:orchestrator-cli-stateless-services for manually deploying MDS daemons on the CLI.