ceph-mon(8)

ceph-mon8

Ceph monitor daemon

Usage

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

Overview

ceph-mon is the cluster monitor daemon for the Ceph distributed file system. One or more instances of ceph-mon form a Paxos part-time parliament cluster that provides extremely reliable and durable storage of cluster membership, configuration, and state.

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

Options

-f, --foreground

Foreground: do not daemonize after startup (run in foreground). Do not 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 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.

--setgroup grouporgid

Set gid after starting. If a group name is specified the group record 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 during startup.

--mkfs

Initialize the mon data directory with seed information to form and initial ceph file system or to join an existing monitor cluster. Three pieces of information must be provided:

•

The cluster fsid. This can come from a monmap (--monmap <path>) or explicitly via --fsid <uuid>.

•

A list of monitors and their addresses. This list of monitors can come from a monmap (--monmap <path>), the mon host configuration value (in ceph.conf or via -m host1,host2,...), or (for backward compatibility) the deprecated mon addr lines in ceph.conf. If this monitor is to be part of the initial monitor quorum for a new Ceph 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 public subnet options may be used.

•

The monitor secret key mon.. This must be included in the keyring 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 provided or the default, to run the daemon. This will entail providing all necessary options to the daemon as arguments.

Releases

6 releases since Debian 8 (Jessie); the text changed 5 times.

  1. 8
  2. 9
  3. 10
  4. 11
  5. 12
  6. 13

--no-config-file since Debian 12 (Bookworm); --setgroup since Debian 9 (Stretch); --setuser since Debian 9 (Stretch).

Availability

ceph-mon is part of Ceph, a massively scalable, open-source, distributed storage system. Please refer to the Ceph documentation at https://docs.ceph.com for more information.

From ceph-mon 18.2.7+ds-1+deb13u1 in Debian 13 (Trixie). Parsed by carta from the page's man source.