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|
:orphan:
=========================================
ceph-mds -- ceph metadata server daemon
=========================================
.. program:: ceph-mds
Synopsis
========
| **ceph-mds** -i *name* [ --hot-standby [*rank*] ]
Description
===========
**ceph-mds** is the metadata server daemon for the Ceph distributed file
system. One or more instances of ceph-mds collectively manage the file
system namespace, coordinating access to the shared OSD cluster.
Each ceph-mds daemon instance should have a unique name. The name is used
to identify daemon instances in the ceph.conf.
Once the daemon has started, the monitor cluster will normally assign
it a logical rank, or put it in a standby pool to take over for
another daemon that crashes. Some of the specified options can cause
other behaviors.
If you specify hot-standby, you must either specify the rank on the command
line, or specify one of the mds_standby_for_[rank|name] parameters in the
config. The command line specification overrides the config, and specifying
the rank overrides specifying the name.
Options
=======
.. option:: -f, --foreground
Foreground: do not daemonize after startup (run in foreground). Do
not generate a pid file. Useful when run via :doc:`ceph-run
<ceph-run>`\(8).
.. option:: -d
Debug mode: like ``-f``, but also send all log output to stderr.
.. option:: --setuser userorgid
Set uid after starting. If a username is specified, the user
record is looked up to get a uid and a gid, and the gid is also set
as well, unless --setgroup is also specified.
.. option:: --setgroup grouporgid
Set gid after starting. If a group name is specified the group
record is looked up to get a gid.
.. option:: -c ceph.conf, --conf=ceph.conf
Use *ceph.conf* configuration file instead of the default
``/etc/ceph/ceph.conf`` to determine monitor addresses during
startup.
.. option:: -m monaddress[:port]
Connect to specified monitor (instead of looking through
``ceph.conf``).
.. option:: --hot-standby <rank>
Start as a hot standby for MDS <rank>.
Availability
============
**ceph-mds** is part of Ceph, a massively scalable, open-source, distributed storage system. Please refer to the Ceph documentation at
http://ceph.com/docs for more information.
See also
========
:doc:`ceph <ceph>`\(8),
:doc:`ceph-mon <ceph-mon>`\(8),
:doc:`ceph-osd <ceph-osd>`\(8)
|
