From 19fcec84d8d7d21e796c7624e521b60d28ee21ed Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:45:59 +0200 Subject: Adding upstream version 16.2.11+ds. Signed-off-by: Daniel Baumann --- doc/cephadm/services/mon.rst | 179 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 179 insertions(+) create mode 100644 doc/cephadm/services/mon.rst (limited to 'doc/cephadm/services/mon.rst') diff --git a/doc/cephadm/services/mon.rst b/doc/cephadm/services/mon.rst new file mode 100644 index 000000000..6326b73f4 --- /dev/null +++ b/doc/cephadm/services/mon.rst @@ -0,0 +1,179 @@ +=========== +MON Service +=========== + +.. _deploy_additional_monitors: + +Deploying additional monitors +============================= + +A typical Ceph cluster has three or five monitor daemons that are spread +across different hosts. We recommend deploying five monitors if there are +five or more nodes in your cluster. + +.. _CIDR: https://en.wikipedia.org/wiki/Classless_Inter-Domain_Routing#CIDR_notation + +Ceph deploys monitor daemons automatically as the cluster grows and Ceph +scales back monitor daemons automatically as the cluster shrinks. The +smooth execution of this automatic growing and shrinking depends upon +proper subnet configuration. + +The cephadm bootstrap procedure assigns the first monitor daemon in the +cluster to a particular subnet. ``cephadm`` designates that subnet as the +default subnet of the cluster. New monitor daemons will be assigned by +default to that subnet unless cephadm is instructed to do otherwise. + +If all of the ceph monitor daemons in your cluster are in the same subnet, +manual administration of the ceph monitor daemons is not necessary. +``cephadm`` will automatically add up to five monitors to the subnet, as +needed, as new hosts are added to the cluster. + +By default, cephadm will deploy 5 daemons on arbitrary hosts. See +:ref:`orchestrator-cli-placement-spec` for details of specifying +the placement of daemons. + +Designating a Particular Subnet for Monitors +-------------------------------------------- + +To designate a particular IP subnet for use by ceph monitor daemons, use a +command of the following form, including the subnet's address in `CIDR`_ +format (e.g., ``10.1.2.0/24``): + + .. prompt:: bash # + + ceph config set mon public_network ** + + For example: + + .. prompt:: bash # + + ceph config set mon public_network 10.1.2.0/24 + +Cephadm deploys new monitor daemons only on hosts that have IP addresses in +the designated subnet. + +You can also specify two public networks by using a list of networks: + + .. prompt:: bash # + + ceph config set mon public_network *,* + + For example: + + .. prompt:: bash # + + ceph config set mon public_network 10.1.2.0/24,192.168.0.1/24 + + +Deploying Monitors on a Particular Network +------------------------------------------ + +You can explicitly specify the IP address or CIDR network for each monitor and +control where each monitor is placed. To disable automated monitor deployment, +run this command: + + .. prompt:: bash # + + ceph orch apply mon --unmanaged + + To deploy each additional monitor: + + .. prompt:: bash # + + ceph orch daemon add mon * + + For example, to deploy a second monitor on ``newhost1`` using an IP + address ``10.1.2.123`` and a third monitor on ``newhost2`` in + network ``10.1.2.0/24``, run the following commands: + + .. prompt:: bash # + + ceph orch apply mon --unmanaged + ceph orch daemon add mon newhost1:10.1.2.123 + ceph orch daemon add mon newhost2:10.1.2.0/24 + + Now, enable automatic placement of Daemons + + .. prompt:: bash # + + ceph orch apply mon --placement="newhost1,newhost2,newhost3" --dry-run + + See :ref:`orchestrator-cli-placement-spec` for details of specifying + the placement of daemons. + + Finally apply this new placement by dropping ``--dry-run`` + + .. prompt:: bash # + + ceph orch apply mon --placement="newhost1,newhost2,newhost3" + + +Moving Monitors to a Different Network +-------------------------------------- + +To move Monitors to a new network, deploy new monitors on the new network and +subsequently remove monitors from the old network. It is not advised to +modify and inject the ``monmap`` manually. + +First, disable the automated placement of daemons: + + .. prompt:: bash # + + ceph orch apply mon --unmanaged + +To deploy each additional monitor: + + .. prompt:: bash # + + ceph orch daemon add mon ** + +For example, to deploy a second monitor on ``newhost1`` using an IP +address ``10.1.2.123`` and a third monitor on ``newhost2`` in +network ``10.1.2.0/24``, run the following commands: + + .. prompt:: bash # + + ceph orch apply mon --unmanaged + ceph orch daemon add mon newhost1:10.1.2.123 + ceph orch daemon add mon newhost2:10.1.2.0/24 + + Subsequently remove monitors from the old network: + + .. prompt:: bash # + + ceph orch daemon rm *mon.* + + Update the ``public_network``: + + .. prompt:: bash # + + ceph config set mon public_network ** + + For example: + + .. prompt:: bash # + + ceph config set mon public_network 10.1.2.0/24 + + Now, enable automatic placement of Daemons + + .. prompt:: bash # + + ceph orch apply mon --placement="newhost1,newhost2,newhost3" --dry-run + + See :ref:`orchestrator-cli-placement-spec` for details of specifying + the placement of daemons. + + Finally apply this new placement by dropping ``--dry-run`` + + .. prompt:: bash # + + ceph orch apply mon --placement="newhost1,newhost2,newhost3" + +Futher Reading +============== + +* :ref:`rados-operations` +* :ref:`rados-troubleshooting-mon` +* :ref:`cephadm-restore-quorum` + -- cgit v1.2.3