Cephadm Operations
==================
+.. _watching_cephadm_logs:
+
Watching cephadm log messages
=============================
-Cephadm logs to the ``cephadm`` cluster log channel, meaning you can
-monitor progress in realtime with::
+Cephadm writes logs to the ``cephadm`` cluster log channel. You can
+monitor Ceph's activity in real time by reading the logs as they fill
+up. Run the following command to see the logs in real time:
+
+.. prompt:: bash #
+
+ ceph -W cephadm
+
+By default, this command shows info-level events and above. To see
+debug-level messages as well as info-level events, run the following
+commands:
+
+.. prompt:: bash #
- # ceph -W cephadm
+ ceph config set mgr mgr/cephadm/log_to_cluster_level debug
+ ceph -W cephadm --watch-debug
-By default it will show info-level events and above. To see
-debug-level messages too::
+.. warning::
- # ceph config set mgr mgr/cephadm/log_to_cluster_level debug
- # ceph -W cephadm --watch-debug
+ The debug messages are very verbose!
-Be careful: the debug messages are very verbose!
+You can see recent events by running the following command:
-You can see recent events with::
+.. prompt:: bash #
- # ceph log last cephadm
+ ceph log last cephadm
These events are also logged to the ``ceph.cephadm.log`` file on
-monitor hosts and to the monitor daemons' stderr.
+monitor hosts as well as to the monitor daemons' stderr.
.. _cephadm-logs:
Ceph daemon logs
================
-Logging to stdout
------------------
+Logging to journald
+-------------------
-Traditionally, Ceph daemons have logged to ``/var/log/ceph``. By
-default, cephadm daemons log to stderr and the logs are
-captured by the container runtime environment. For most systems, by
-default, these logs are sent to journald and accessible via
-``journalctl``.
+Ceph daemons traditionally write logs to ``/var/log/ceph``. Ceph daemons log to
+journald by default and Ceph logs are captured by the container runtime
+environment. They are accessible via ``journalctl``.
+
+.. note:: Prior to Quincy, ceph daemons logged to stderr.
+
+Example of logging to journald
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
For example, to view the logs for the daemon ``mon.foo`` for a cluster
with ID ``5c5a50ae-272a-455d-99e9-32c6a013e694``, the command would be
-something like::
+something like:
+
+.. prompt:: bash #
journalctl -u ceph-5c5a50ae-272a-455d-99e9-32c6a013e694@mon.foo
This works well for normal operations when logging levels are low.
-To disable logging to stderr::
-
- ceph config set global log_to_stderr false
- ceph config set global mon_cluster_log_to_stderr false
-
Logging to files
----------------
-You can also configure Ceph daemons to log to files instead of stderr,
-just like they have in the past. When logging to files, Ceph logs appear
-in ``/var/log/ceph/<cluster-fsid>``.
+You can also configure Ceph daemons to log to files instead of to
+journald if you prefer logs to appear in files (as they did in earlier,
+pre-cephadm, pre-Octopus versions of Ceph). When Ceph logs to files,
+the logs appear in ``/var/log/ceph/<cluster-fsid>``. If you choose to
+configure Ceph to log to files instead of to journald, remember to
+configure Ceph so that it will not log to journald (the commands for
+this are covered below).
+
+Enabling logging to files
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+To enable logging to files, run the following commands:
-To enable logging to files::
+.. prompt:: bash #
ceph config set global log_to_file true
ceph config set global mon_cluster_log_to_file true
-We recommend disabling logging to stderr (see above) or else everything
-will be logged twice::
+Disabling logging to journald
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+If you choose to log to files, we recommend disabling logging to journald or else
+everything will be logged twice. Run the following commands to disable logging
+to stderr:
+
+.. prompt:: bash #
ceph config set global log_to_stderr false
ceph config set global mon_cluster_log_to_stderr false
+ ceph config set global log_to_journald false
+ ceph config set global mon_cluster_log_to_journald false
+
+.. note:: You can change the default by passing --log-to-file during
+ bootstrapping a new cluster.
+
+Modifying the log retention schedule
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
By default, cephadm sets up log rotation on each host to rotate these
files. You can configure the logging retention schedule by modifying
Data location
=============
-Cephadm daemon data and logs in slightly different locations than older
-versions of ceph:
+Cephadm stores daemon data and logs in different locations than did
+older, pre-cephadm (pre Octopus) versions of ceph:
-* ``/var/log/ceph/<cluster-fsid>`` contains all cluster logs. Note
- that by default cephadm logs via stderr and the container runtime,
- so these logs are normally not present.
+* ``/var/log/ceph/<cluster-fsid>`` contains all cluster logs. By
+ default, cephadm logs via stderr and the container runtime. These
+ logs will not exist unless you have enabled logging to files as
+ described in `cephadm-logs`_.
* ``/var/lib/ceph/<cluster-fsid>`` contains all cluster daemon data
(besides logs).
* ``/var/lib/ceph/<cluster-fsid>/<daemon-name>`` contains all data for
Disk usage
----------
-Because a few Ceph daemons may store a significant amount of data in
-``/var/lib/ceph`` (notably, the monitors and prometheus), we recommend
-moving this directory to its own disk, partition, or logical volume so
-that it does not fill up the root file system.
+Because a few Ceph daemons (notably, the monitors and prometheus) store a
+large amount of data in ``/var/lib/ceph`` , we recommend moving this
+directory to its own disk, partition, or logical volume so that it does not
+fill up the root file system.
+Health checks
+=============
+The cephadm module provides additional health checks to supplement the
+default health checks provided by the Cluster. These additional health
+checks fall into two categories:
-SSH Configuration
-=================
+- **cephadm operations**: Health checks in this category are always
+ executed when the cephadm module is active.
+- **cluster configuration**: These health checks are *optional*, and
+ focus on the configuration of the hosts in the cluster.
-Cephadm uses SSH to connect to remote hosts. SSH uses a key to authenticate
-with those hosts in a secure way.
+CEPHADM Operations
+------------------
+CEPHADM_PAUSED
+~~~~~~~~~~~~~~
-Default behavior
-----------------
+This indicates that cephadm background work has been paused with
+``ceph orch pause``. Cephadm continues to perform passive monitoring
+activities (like checking host and daemon status), but it will not
+make any changes (like deploying or removing daemons).
-Cephadm stores an SSH key in the monitor that is used to
-connect to remote hosts. When the cluster is bootstrapped, this SSH
-key is generated automatically and no additional configuration
-is necessary.
+Resume cephadm work by running the following command:
-A *new* SSH key can be generated with::
+.. prompt:: bash #
- ceph cephadm generate-key
+ ceph orch resume
-The public portion of the SSH key can be retrieved with::
+.. _cephadm-stray-host:
- ceph cephadm get-pub-key
+CEPHADM_STRAY_HOST
+~~~~~~~~~~~~~~~~~~
-The currently stored SSH key can be deleted with::
+This indicates that one or more hosts have Ceph daemons that are
+running, but are not registered as hosts managed by *cephadm*. This
+means that those services cannot currently be managed by cephadm
+(e.g., restarted, upgraded, included in `ceph orch ps`).
- ceph cephadm clear-key
+* You can manage the host(s) by running the following command:
-You can make use of an existing key by directly importing it with::
+ .. prompt:: bash #
- ceph config-key set mgr/cephadm/ssh_identity_key -i <key>
- ceph config-key set mgr/cephadm/ssh_identity_pub -i <pub>
+ ceph orch host add *<hostname>*
-You will then need to restart the mgr daemon to reload the configuration with::
+ .. note::
- ceph mgr fail
+ You might need to configure SSH access to the remote host
+ before this will work.
+* See :ref:`cephadm-fqdn` for more information about host names and
+ domain names.
-Customizing the SSH configuration
----------------------------------
+* Alternatively, you can manually connect to the host and ensure that
+ services on that host are removed or migrated to a host that is
+ managed by *cephadm*.
-Cephadm generates an appropriate ``ssh_config`` file that is
-used for connecting to remote hosts. This configuration looks
-something like this::
+* This warning can be disabled entirely by running the following
+ command:
- Host *
- User root
- StrictHostKeyChecking no
- UserKnownHostsFile /dev/null
+ .. prompt:: bash #
-There are two ways to customize this configuration for your environment:
+ ceph config set mgr mgr/cephadm/warn_on_stray_hosts false
-#. Import a customized configuration file that will be stored
- by the monitor with::
+CEPHADM_STRAY_DAEMON
+~~~~~~~~~~~~~~~~~~~~
- ceph cephadm set-ssh-config -i <ssh_config_file>
+One or more Ceph daemons are running but not are not managed by
+*cephadm*. This may be because they were deployed using a different
+tool, or because they were started manually. Those
+services cannot currently be managed by cephadm (e.g., restarted,
+upgraded, or included in `ceph orch ps`).
- To remove a customized SSH config and revert back to the default behavior::
+* If the daemon is a stateful one (monitor or OSD), it should be adopted
+ by cephadm; see :ref:`cephadm-adoption`. For stateless daemons, it is
+ usually easiest to provision a new daemon with the ``ceph orch apply``
+ command and then stop the unmanaged daemon.
- ceph cephadm clear-ssh-config
+* If the stray daemon(s) are running on hosts not managed by cephadm, you can manage the host(s) by running the following command:
-#. You can configure a file location for the SSH configuration file with::
+ .. prompt:: bash #
- ceph config set mgr mgr/cephadm/ssh_config_file <path>
+ ceph orch host add *<hostname>*
- We do *not recommend* this approach. The path name must be
- visible to *any* mgr daemon, and cephadm runs all daemons as
- containers. That means that the file either need to be placed
- inside a customized container image for your deployment, or
- manually distributed to the mgr data directory
- (``/var/lib/ceph/<cluster-fsid>/mgr.<id>`` on the host, visible at
- ``/var/lib/ceph/mgr/ceph-<id>`` from inside the container).
+ .. note::
+ You might need to configure SSH access to the remote host
+ before this will work.
-Health checks
-=============
+* See :ref:`cephadm-fqdn` for more information about host names and
+ domain names.
-CEPHADM_PAUSED
---------------
+* This warning can be disabled entirely by running the following command:
-Cephadm background work has been paused with ``ceph orch pause``. Cephadm
-continues to perform passive monitoring activities (like checking
-host and daemon status), but it will not make any changes (like deploying
-or removing daemons).
+ .. prompt:: bash #
-Resume cephadm work with::
+ ceph config set mgr mgr/cephadm/warn_on_stray_daemons false
- ceph orch resume
+CEPHADM_HOST_CHECK_FAILED
+~~~~~~~~~~~~~~~~~~~~~~~~~
-CEPHADM_STRAY_HOST
-------------------
+One or more hosts have failed the basic cephadm host check, which verifies
+that (1) the host is reachable and cephadm can be executed there, and (2)
+that the host satisfies basic prerequisites, like a working container
+runtime (podman or docker) and working time synchronization.
+If this test fails, cephadm will no be able to manage services on that host.
-One or more hosts have running Ceph daemons but are not registered as
-hosts managed by *cephadm*. This means that those services cannot
-currently be managed by cephadm (e.g., restarted, upgraded, included
-in `ceph orch ps`).
+You can manually run this check by running the following command:
-You can manage the host(s) with::
+.. prompt:: bash #
- ceph orch host add *<hostname>*
+ ceph cephadm check-host *<hostname>*
-Note that you may need to configure SSH access to the remote host
-before this will work.
+You can remove a broken host from management by running the following command:
-Alternatively, you can manually connect to the host and ensure that
-services on that host are removed or migrated to a host that is
-managed by *cephadm*.
+.. prompt:: bash #
-You can also disable this warning entirely with::
+ ceph orch host rm *<hostname>*
- ceph config set mgr mgr/cephadm/warn_on_stray_hosts false
+You can disable this health warning by running the following command:
-CEPHADM_STRAY_DAEMON
---------------------
+.. prompt:: bash #
-One or more Ceph daemons are running but not are not managed by
-*cephadm*. This may be because they were deployed using a different
-tool, or because they were started manually. Those
-services cannot currently be managed by cephadm (e.g., restarted,
-upgraded, or included in `ceph orch ps`).
+ ceph config set mgr mgr/cephadm/warn_on_failed_host_check false
-If the daemon is a stateful one (monitor or OSD), it should be adopted
-by cephadm; see :ref:`cephadm-adoption`. For stateless daemons, it is
-usually easiest to provision a new daemon with the ``ceph orch apply``
-command and then stop the unmanaged daemon.
+Cluster Configuration Checks
+----------------------------
+Cephadm periodically scans each of the hosts in the cluster in order
+to understand the state of the OS, disks, NICs etc. These facts can
+then be analysed for consistency across the hosts in the cluster to
+identify any configuration anomalies.
-This warning can be disabled entirely with::
+Enabling Cluster Configuration Checks
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- ceph config set mgr mgr/cephadm/warn_on_stray_daemons false
+The configuration checks are an **optional** feature, and are enabled
+by running the following command:
-CEPHADM_HOST_CHECK_FAILED
--------------------------
+.. prompt:: bash #
-One or more hosts have failed the basic cephadm host check, which verifies
-that (1) the host is reachable and cephadm can be executed there, and (2)
-that the host satisfies basic prerequisites, like a working container
-runtime (podman or docker) and working time synchronization.
-If this test fails, cephadm will no be able to manage services on that host.
+ ceph config set mgr mgr/cephadm/config_checks_enabled true
-You can manually run this check with::
+States Returned by Cluster Configuration Checks
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- ceph cephadm check-host *<hostname>*
+The configuration checks are triggered after each host scan (1m). The
+cephadm log entries will show the current state and outcome of the
+configuration checks as follows:
-You can remove a broken host from management with::
+Disabled state (config_checks_enabled false):
- ceph orch host rm *<hostname>*
+.. code-block:: bash
-You can disable this health warning with::
+ ALL cephadm checks are disabled, use 'ceph config set mgr mgr/cephadm/config_checks_enabled true' to enable
- ceph config set mgr mgr/cephadm/warn_on_failed_host_check false
+Enabled state (config_checks_enabled true):
+
+.. code-block:: bash
+
+ CEPHADM 8/8 checks enabled and executed (0 bypassed, 0 disabled). No issues detected
+
+Managing Configuration Checks (subcommands)
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The configuration checks themselves are managed through several cephadm subcommands.
+
+To determine whether the configuration checks are enabled, run the following command:
+
+.. prompt:: bash #
+
+ ceph cephadm config-check status
+
+This command returns the status of the configuration checker as either "Enabled" or "Disabled".
+
+
+To list all the configuration checks and their current states, run the following command:
+
+.. code-block:: console
+
+ # ceph cephadm config-check ls
+
+ NAME HEALTHCHECK STATUS DESCRIPTION
+ kernel_security CEPHADM_CHECK_KERNEL_LSM enabled checks SELINUX/Apparmor profiles are consistent across cluster hosts
+ os_subscription CEPHADM_CHECK_SUBSCRIPTION enabled checks subscription states are consistent for all cluster hosts
+ public_network CEPHADM_CHECK_PUBLIC_MEMBERSHIP enabled check that all hosts have a NIC on the Ceph public_netork
+ osd_mtu_size CEPHADM_CHECK_MTU enabled check that OSD hosts share a common MTU setting
+ osd_linkspeed CEPHADM_CHECK_LINKSPEED enabled check that OSD hosts share a common linkspeed
+ network_missing CEPHADM_CHECK_NETWORK_MISSING enabled checks that the cluster/public networks defined exist on the Ceph hosts
+ ceph_release CEPHADM_CHECK_CEPH_RELEASE enabled check for Ceph version consistency - ceph daemons should be on the same release (unless upgrade is active)
+ kernel_version CEPHADM_CHECK_KERNEL_VERSION enabled checks that the MAJ.MIN of the kernel on Ceph hosts is consistent
+
+The name of each configuration check can be used to enable or disable a specific check by running a command of the following form:
+:
+
+.. prompt:: bash #
+
+ ceph cephadm config-check disable <name>
+
+For example:
+
+.. prompt:: bash #
+
+ ceph cephadm config-check disable kernel_security
+
+CEPHADM_CHECK_KERNEL_LSM
+~~~~~~~~~~~~~~~~~~~~~~~~
+Each host within the cluster is expected to operate within the same Linux
+Security Module (LSM) state. For example, if the majority of the hosts are
+running with SELINUX in enforcing mode, any host not running in this mode is
+flagged as an anomaly and a healtcheck (WARNING) state raised.
+
+CEPHADM_CHECK_SUBSCRIPTION
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+This check relates to the status of vendor subscription. This check is
+performed only for hosts using RHEL, but helps to confirm that all hosts are
+covered by an active subscription, which ensures that patches and updates are
+available.
+
+CEPHADM_CHECK_PUBLIC_MEMBERSHIP
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+All members of the cluster should have NICs configured on at least one of the
+public network subnets. Hosts that are not on the public network will rely on
+routing, which may affect performance.
+
+CEPHADM_CHECK_MTU
+~~~~~~~~~~~~~~~~~
+The MTU of the NICs on OSDs can be a key factor in consistent performance. This
+check examines hosts that are running OSD services to ensure that the MTU is
+configured consistently within the cluster. This is determined by establishing
+the MTU setting that the majority of hosts is using. Any anomalies result in a
+Ceph health check.
+
+CEPHADM_CHECK_LINKSPEED
+~~~~~~~~~~~~~~~~~~~~~~~
+This check is similar to the MTU check. Linkspeed consistency is a factor in
+consistent cluster performance, just as the MTU of the NICs on the OSDs is.
+This check determines the linkspeed shared by the majority of OSD hosts, and a
+health check is run for any hosts that are set at a lower linkspeed rate.
+
+CEPHADM_CHECK_NETWORK_MISSING
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+The `public_network` and `cluster_network` settings support subnet definitions
+for IPv4 and IPv6. If these settings are not found on any host in the cluster,
+a health check is raised.
+
+CEPHADM_CHECK_CEPH_RELEASE
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+Under normal operations, the Ceph cluster runs daemons under the same ceph
+release (that is, the Ceph cluster runs all daemons under (for example)
+Octopus). This check determines the active release for each daemon, and
+reports any anomalies as a healthcheck. *This check is bypassed if an upgrade
+process is active within the cluster.*
+
+CEPHADM_CHECK_KERNEL_VERSION
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+The OS kernel version (maj.min) is checked for consistency across the hosts.
+The kernel version of the majority of the hosts is used as the basis for
+identifying anomalies.
+
+.. _client_keyrings_and_configs:
+
+Client keyrings and configs
+===========================
+
+Cephadm can distribute copies of the ``ceph.conf`` file and client keyring
+files to hosts. It is usually a good idea to store a copy of the config and
+``client.admin`` keyring on any host used to administer the cluster via the
+CLI. By default, cephadm does this for any nodes that have the ``_admin``
+label (which normally includes the bootstrap host).
+
+When a client keyring is placed under management, cephadm will:
+
+ - build a list of target hosts based on the specified placement spec (see
+ :ref:`orchestrator-cli-placement-spec`)
+ - store a copy of the ``/etc/ceph/ceph.conf`` file on the specified host(s)
+ - store a copy of the keyring file on the specified host(s)
+ - update the ``ceph.conf`` file as needed (e.g., due to a change in the cluster monitors)
+ - update the keyring file if the entity's key is changed (e.g., via ``ceph
+ auth ...`` commands)
+ - ensure that the keyring file has the specified ownership and specified mode
+ - remove the keyring file when client keyring management is disabled
+ - remove the keyring file from old hosts if the keyring placement spec is
+ updated (as needed)
+
+Listing Client Keyrings
+-----------------------
+
+To see the list of client keyrings are currently under management, run the following command:
+
+.. prompt:: bash #
+
+ ceph orch client-keyring ls
+
+Putting a Keyring Under Management
+----------------------------------
+
+To put a keyring under management, run a command of the following form:
+
+.. prompt:: bash #
+
+ ceph orch client-keyring set <entity> <placement> [--mode=<mode>] [--owner=<uid>.<gid>] [--path=<path>]
+
+- By default, the *path* is ``/etc/ceph/client.{entity}.keyring``, which is
+ where Ceph looks by default. Be careful when specifying alternate locations,
+ as existing files may be overwritten.
+- A placement of ``*`` (all hosts) is common.
+- The mode defaults to ``0600`` and ownership to ``0:0`` (user root, group root).
+
+For example, to create a ``client.rbd`` key and deploy it to hosts with the
+``rbd-client`` label and make it group readable by uid/gid 107 (qemu), run the
+following commands:
+
+.. prompt:: bash #
+
+ ceph auth get-or-create-key client.rbd mon 'profile rbd' mgr 'profile rbd' osd 'profile rbd pool=my_rbd_pool'
+ ceph orch client-keyring set client.rbd label:rbd-client --owner 107:107 --mode 640
+
+The resulting keyring file is:
+
+.. code-block:: console
+
+ -rw-r-----. 1 qemu qemu 156 Apr 21 08:47 /etc/ceph/client.client.rbd.keyring
+
+Disabling Management of a Keyring File
+--------------------------------------
+
+To disable management of a keyring file, run a command of the following form:
+
+.. prompt:: bash #
+
+ ceph orch client-keyring rm <entity>
+
+.. note::
+
+ This deletes any keyring files for this entity that were previously written
+ to cluster nodes.
+
+.. _etc_ceph_conf_distribution:
+
+/etc/ceph/ceph.conf
+===================
+
+Distributing ceph.conf to hosts that have no keyrings
+-----------------------------------------------------
+
+It might be useful to distribute ``ceph.conf`` files to hosts without an
+associated client keyring file. By default, cephadm deploys only a
+``ceph.conf`` file to hosts where a client keyring is also distributed (see
+above). To write config files to hosts without client keyrings, run the
+following command:
+
+.. prompt:: bash #
+
+ ceph config set mgr mgr/cephadm/manage_etc_ceph_ceph_conf true
+
+Using Placement Specs to specify which hosts get keyrings
+---------------------------------------------------------
+
+By default, the configs are written to all hosts (i.e., those listed by ``ceph
+orch host ls``). To specify which hosts get a ``ceph.conf``, run a command of
+the following form:
+
+.. prompt:: bash #
+
+ ceph config set mgr mgr/cephadm/manage_etc_ceph_ceph_conf_hosts <placement spec>
+
+For example, to distribute configs to hosts with the ``bare_config`` label, run
+the following command:
+
+Distributing ceph.conf to hosts tagged with bare_config
+-------------------------------------------------------
+
+For example, to distribute configs to hosts with the ``bare_config`` label, run the following command:
+
+.. prompt:: bash #
+
+ ceph config set mgr mgr/cephadm/manage_etc_ceph_ceph_conf_hosts label:bare_config
+
+(See :ref:`orchestrator-cli-placement-spec` for more information about placement specs.)
+
+Purging a cluster
+=================
+
+.. danger:: THIS OPERATION WILL DESTROY ALL DATA STORED IN THIS CLUSTER
+
+In order to destroy a cluster and delete all data stored in this cluster, pause
+cephadm to avoid deploying new daemons.
+
+.. prompt:: bash #
+
+ ceph orch pause
+
+Then verify the FSID of the cluster:
+
+.. prompt:: bash #
+
+ ceph fsid
+
+Purge ceph daemons from all hosts in the cluster
+
+.. prompt:: bash #
+
+ # For each host:
+ cephadm rm-cluster --force --zap-osds --fsid <fsid>