ceph-mon – ceph monitor daemon

Synopsis

ceph-mon -i monid [ –mon-data mondatapath ]

Description

ceph-mon is the cluster monitor daemon for the Ceph distributedfile system. One or more instances of ceph-mon form a Paxospart-time parliament cluster that provides extremely reliable anddurable storage of cluster membership, configuration, and state.

The mondatapath refers to a directory on a local file system storingmonitor data. It is normally specified via the mon data option inthe configuration file.

Options

  • -f, —foreground
  • Foreground: do not daemonize after startup (run in foreground). Donot generate a pid file. Useful when run via ceph-run(8).
  • -d
  • Debug mode: like -f, but also send all log output to stderr.
  • —setuser userorgid
  • Set uid after starting. If a username is specified, the userrecord is looked up to get a uid and a gid, and the gid is also setas well, unless –setgroup is also specified.
  • —setgroup grouporgid
  • Set gid after starting. If a group name is specified the grouprecord is looked up to get a gid.
  • -c ceph.conf, —conf=ceph.conf
  • Use ceph.conf configuration file instead of the default/etc/ceph/ceph.conf to determine monitor addresses duringstartup.
  • —mkfs

  • Initialize the mon data directory with seed information to formand initial ceph file system or to join an existing monitorcluster. Three pieces of information must be provided:

    • The cluster fsid. This can come from a monmap (—monmap <path>) orexplicitly via —fsid <uuid>.

    • A list of monitors and their addresses. This list of monitorscan come from a monmap (—monmap <path>), the mon hostconfiguration value (in ceph.conf or via -mhost1,host2,…), or (for backward compatibility) the deprecated mon addr lines in ceph.conf. If thismonitor is to be part of the initial monitor quorum for a newCeph cluster, then it must be included in the initial list,matching either the name or address of a monitor in the list.When matching by address, either the public addr or publicsubnet options may be used.

    • The monitor secret key mon.. This must be included in thekeyring provided via —keyring <path>.

  • —keyring
  • Specify a keyring for use with —mkfs.
  • —no-config-file
  • Signal that we don’t want to rely on a ceph.conf, either user providedor the default, to run the daemon. This will entail providing allnecessary options to the daemon as arguments.

Availability

ceph-mon is part of Ceph, a massively scalable, open-source, distributed storage system. Please referto the Ceph documentation at http://ceph.com/docs for moreinformation.

See also

ceph(8),ceph-mds(8),ceph-osd(8)