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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-21 11:54:28 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-21 11:54:28 +0000 |
commit | e6918187568dbd01842d8d1d2c808ce16a894239 (patch) | |
tree | 64f88b554b444a49f656b6c656111a145cbbaa28 /doc/rados/operations/control.rst | |
parent | Initial commit. (diff) | |
download | ceph-e6918187568dbd01842d8d1d2c808ce16a894239.tar.xz ceph-e6918187568dbd01842d8d1d2c808ce16a894239.zip |
Adding upstream version 18.2.2.upstream/18.2.2
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'doc/rados/operations/control.rst')
-rw-r--r-- | doc/rados/operations/control.rst | 665 |
1 files changed, 665 insertions, 0 deletions
diff --git a/doc/rados/operations/control.rst b/doc/rados/operations/control.rst new file mode 100644 index 000000000..033f831cd --- /dev/null +++ b/doc/rados/operations/control.rst @@ -0,0 +1,665 @@ +.. index:: control, commands + +================== + Control Commands +================== + + +Monitor Commands +================ + +To issue monitor commands, use the ``ceph`` utility: + +.. prompt:: bash $ + + ceph [-m monhost] {command} + +In most cases, monitor commands have the following form: + +.. prompt:: bash $ + + ceph {subsystem} {command} + + +System Commands +=============== + +To display the current cluster status, run the following commands: + +.. prompt:: bash $ + + ceph -s + ceph status + +To display a running summary of cluster status and major events, run the +following command: + +.. prompt:: bash $ + + ceph -w + +To display the monitor quorum, including which monitors are participating and +which one is the leader, run the following commands: + +.. prompt:: bash $ + + ceph mon stat + ceph quorum_status + +To query the status of a single monitor, including whether it is in the quorum, +run the following command: + +.. prompt:: bash $ + + ceph tell mon.[id] mon_status + +Here the value of ``[id]`` can be found by consulting the output of ``ceph +-s``. + + +Authentication Subsystem +======================== + +To add an OSD keyring for a specific OSD, run the following command: + +.. prompt:: bash $ + + ceph auth add {osd} {--in-file|-i} {path-to-osd-keyring} + +To list the cluster's keys and their capabilities, run the following command: + +.. prompt:: bash $ + + ceph auth ls + + +Placement Group Subsystem +========================= + +To display the statistics for all placement groups (PGs), run the following +command: + +.. prompt:: bash $ + + ceph pg dump [--format {format}] + +Here the valid formats are ``plain`` (default), ``json`` ``json-pretty``, +``xml``, and ``xml-pretty``. When implementing monitoring tools and other +tools, it is best to use the ``json`` format. JSON parsing is more +deterministic than the ``plain`` format (which is more human readable), and the +layout is much more consistent from release to release. The ``jq`` utility is +very useful for extracting data from JSON output. + +To display the statistics for all PGs stuck in a specified state, run the +following command: + +.. prompt:: bash $ + + ceph pg dump_stuck inactive|unclean|stale|undersized|degraded [--format {format}] [-t|--threshold {seconds}] + +Here ``--format`` may be ``plain`` (default), ``json``, ``json-pretty``, +``xml``, or ``xml-pretty``. + +The ``--threshold`` argument determines the time interval (in seconds) for a PG +to be considered ``stuck`` (default: 300). + +PGs might be stuck in any of the following states: + +**Inactive** + + PGs are unable to process reads or writes because they are waiting for an + OSD that has the most up-to-date data to return to an ``up`` state. + + +**Unclean** + + PGs contain objects that have not been replicated the desired number of + times. These PGs have not yet completed the process of recovering. + + +**Stale** + + PGs are in an unknown state, because the OSDs that host them have not + reported to the monitor cluster for a certain period of time (specified by + the ``mon_osd_report_timeout`` configuration setting). + + +To delete a ``lost`` object or revert an object to its prior state, either by +reverting it to its previous version or by deleting it because it was just +created and has no previous version, run the following command: + +.. prompt:: bash $ + + ceph pg {pgid} mark_unfound_lost revert|delete + + +.. _osd-subsystem: + +OSD Subsystem +============= + +To query OSD subsystem status, run the following command: + +.. prompt:: bash $ + + ceph osd stat + +To write a copy of the most recent OSD map to a file (see :ref:`osdmaptool +<osdmaptool>`), run the following command: + +.. prompt:: bash $ + + ceph osd getmap -o file + +To write a copy of the CRUSH map from the most recent OSD map to a file, run +the following command: + +.. prompt:: bash $ + + ceph osd getcrushmap -o file + +Note that this command is functionally equivalent to the following two +commands: + +.. prompt:: bash $ + + ceph osd getmap -o /tmp/osdmap + osdmaptool /tmp/osdmap --export-crush file + +To dump the OSD map, run the following command: + +.. prompt:: bash $ + + ceph osd dump [--format {format}] + +The ``--format`` option accepts the following arguments: ``plain`` (default), +``json``, ``json-pretty``, ``xml``, and ``xml-pretty``. As noted above, JSON is +the recommended format for tools, scripting, and other forms of automation. + +To dump the OSD map as a tree that lists one OSD per line and displays +information about the weights and states of the OSDs, run the following +command: + +.. prompt:: bash $ + + ceph osd tree [--format {format}] + +To find out where a specific RADOS object is stored in the system, run a +command of the following form: + +.. prompt:: bash $ + + ceph osd map <pool-name> <object-name> + +To add or move a new OSD (specified by its ID, name, or weight) to a specific +CRUSH location, run the following command: + +.. prompt:: bash $ + + ceph osd crush set {id} {weight} [{loc1} [{loc2} ...]] + +To remove an existing OSD from the CRUSH map, run the following command: + +.. prompt:: bash $ + + ceph osd crush remove {name} + +To remove an existing bucket from the CRUSH map, run the following command: + +.. prompt:: bash $ + + ceph osd crush remove {bucket-name} + +To move an existing bucket from one position in the CRUSH hierarchy to another, +run the following command: + +.. prompt:: bash $ + + ceph osd crush move {id} {loc1} [{loc2} ...] + +To set the CRUSH weight of a specific OSD (specified by ``{name}``) to +``{weight}``, run the following command: + +.. prompt:: bash $ + + ceph osd crush reweight {name} {weight} + +To mark an OSD as ``lost``, run the following command: + +.. prompt:: bash $ + + ceph osd lost {id} [--yes-i-really-mean-it] + +.. warning:: + This could result in permanent data loss. Use with caution! + +To create a new OSD, run the following command: + +.. prompt:: bash $ + + ceph osd create [{uuid}] + +If no UUID is given as part of this command, the UUID will be set automatically +when the OSD starts up. + +To remove one or more specific OSDs, run the following command: + +.. prompt:: bash $ + + ceph osd rm [{id}...] + +To display the current ``max_osd`` parameter in the OSD map, run the following +command: + +.. prompt:: bash $ + + ceph osd getmaxosd + +To import a specific CRUSH map, run the following command: + +.. prompt:: bash $ + + ceph osd setcrushmap -i file + +To set the ``max_osd`` parameter in the OSD map, run the following command: + +.. prompt:: bash $ + + ceph osd setmaxosd + +The parameter has a default value of 10000. Most operators will never need to +adjust it. + +To mark a specific OSD ``down``, run the following command: + +.. prompt:: bash $ + + ceph osd down {osd-num} + +To mark a specific OSD ``out`` (so that no data will be allocated to it), run +the following command: + +.. prompt:: bash $ + + ceph osd out {osd-num} + +To mark a specific OSD ``in`` (so that data will be allocated to it), run the +following command: + +.. prompt:: bash $ + + ceph osd in {osd-num} + +By using the "pause flags" in the OSD map, you can pause or unpause I/O +requests. If the flags are set, then no I/O requests will be sent to any OSD. +When the flags are cleared, then pending I/O requests will be resent. To set or +clear pause flags, run one of the following commands: + +.. prompt:: bash $ + + ceph osd pause + ceph osd unpause + +You can assign an override or ``reweight`` weight value to a specific OSD if +the normal CRUSH distribution seems to be suboptimal. The weight of an OSD +helps determine the extent of its I/O requests and data storage: two OSDs with +the same weight will receive approximately the same number of I/O requests and +store approximately the same amount of data. The ``ceph osd reweight`` command +assigns an override weight to an OSD. The weight value is in the range 0 to 1, +and the command forces CRUSH to relocate a certain amount (1 - ``weight``) of +the data that would otherwise be on this OSD. The command does not change the +weights of the buckets above the OSD in the CRUSH map. Using the command is +merely a corrective measure: for example, if one of your OSDs is at 90% and the +others are at 50%, you could reduce the outlier weight to correct this +imbalance. To assign an override weight to a specific OSD, run the following +command: + +.. prompt:: bash $ + + ceph osd reweight {osd-num} {weight} + +.. note:: Any assigned override reweight value will conflict with the balancer. + This means that if the balancer is in use, all override reweight values + should be ``1.0000`` in order to avoid suboptimal cluster behavior. + +A cluster's OSDs can be reweighted in order to maintain balance if some OSDs +are being disproportionately utilized. Note that override or ``reweight`` +weights have values relative to one another that default to 1.00000; their +values are not absolute, and these weights must be distinguished from CRUSH +weights (which reflect the absolute capacity of a bucket, as measured in TiB). +To reweight OSDs by utilization, run the following command: + +.. prompt:: bash $ + + ceph osd reweight-by-utilization [threshold [max_change [max_osds]]] [--no-increasing] + +By default, this command adjusts the override weight of OSDs that have ±20% of +the average utilization, but you can specify a different percentage in the +``threshold`` argument. + +To limit the increment by which any OSD's reweight is to be changed, use the +``max_change`` argument (default: 0.05). To limit the number of OSDs that are +to be adjusted, use the ``max_osds`` argument (default: 4). Increasing these +variables can accelerate the reweighting process, but perhaps at the cost of +slower client operations (as a result of the increase in data movement). + +You can test the ``osd reweight-by-utilization`` command before running it. To +find out which and how many PGs and OSDs will be affected by a specific use of +the ``osd reweight-by-utilization`` command, run the following command: + +.. prompt:: bash $ + + ceph osd test-reweight-by-utilization [threshold [max_change max_osds]] [--no-increasing] + +The ``--no-increasing`` option can be added to the ``reweight-by-utilization`` +and ``test-reweight-by-utilization`` commands in order to prevent any override +weights that are currently less than 1.00000 from being increased. This option +can be useful in certain circumstances: for example, when you are hastily +balancing in order to remedy ``full`` or ``nearfull`` OSDs, or when there are +OSDs being evacuated or slowly brought into service. + +Operators of deployments that utilize Nautilus or newer (or later revisions of +Luminous and Mimic) and that have no pre-Luminous clients might likely instead +want to enable the `balancer`` module for ``ceph-mgr``. + +The blocklist can be modified by adding or removing an IP address or a CIDR +range. If an address is blocklisted, it will be unable to connect to any OSD. +If an OSD is contained within an IP address or CIDR range that has been +blocklisted, the OSD will be unable to perform operations on its peers when it +acts as a client: such blocked operations include tiering and copy-from +functionality. To add or remove an IP address or CIDR range to the blocklist, +run one of the following commands: + +.. prompt:: bash $ + + ceph osd blocklist ["range"] add ADDRESS[:source_port][/netmask_bits] [TIME] + ceph osd blocklist ["range"] rm ADDRESS[:source_port][/netmask_bits] + +If you add something to the blocklist with the above ``add`` command, you can +use the ``TIME`` keyword to specify the length of time (in seconds) that it +will remain on the blocklist (default: one hour). To add or remove a CIDR +range, use the ``range`` keyword in the above commands. + +Note that these commands are useful primarily in failure testing. Under normal +conditions, blocklists are maintained automatically and do not need any manual +intervention. + +To create or delete a snapshot of a specific storage pool, run one of the +following commands: + +.. prompt:: bash $ + + ceph osd pool mksnap {pool-name} {snap-name} + ceph osd pool rmsnap {pool-name} {snap-name} + +To create, delete, or rename a specific storage pool, run one of the following +commands: + +.. prompt:: bash $ + + ceph osd pool create {pool-name} [pg_num [pgp_num]] + ceph osd pool delete {pool-name} [{pool-name} --yes-i-really-really-mean-it] + ceph osd pool rename {old-name} {new-name} + +To change a pool setting, run the following command: + +.. prompt:: bash $ + + ceph osd pool set {pool-name} {field} {value} + +The following are valid fields: + + * ``size``: The number of copies of data in the pool. + * ``pg_num``: The PG number. + * ``pgp_num``: The effective number of PGs when calculating placement. + * ``crush_rule``: The rule number for mapping placement. + +To retrieve the value of a pool setting, run the following command: + +.. prompt:: bash $ + + ceph osd pool get {pool-name} {field} + +Valid fields are: + + * ``pg_num``: The PG number. + * ``pgp_num``: The effective number of PGs when calculating placement. + +To send a scrub command to a specific OSD, or to all OSDs (by using ``*``), run +the following command: + +.. prompt:: bash $ + + ceph osd scrub {osd-num} + +To send a repair command to a specific OSD, or to all OSDs (by using ``*``), +run the following command: + +.. prompt:: bash $ + + ceph osd repair N + +You can run a simple throughput benchmark test against a specific OSD. This +test writes a total size of ``TOTAL_DATA_BYTES`` (default: 1 GB) incrementally, +in multiple write requests that each have a size of ``BYTES_PER_WRITE`` +(default: 4 MB). The test is not destructive and it will not overwrite existing +live OSD data, but it might temporarily affect the performance of clients that +are concurrently accessing the OSD. To launch this benchmark test, run the +following command: + +.. prompt:: bash $ + + ceph tell osd.N bench [TOTAL_DATA_BYTES] [BYTES_PER_WRITE] + +To clear the caches of a specific OSD during the interval between one benchmark +run and another, run the following command: + +.. prompt:: bash $ + + ceph tell osd.N cache drop + +To retrieve the cache statistics of a specific OSD, run the following command: + +.. prompt:: bash $ + + ceph tell osd.N cache status + +MDS Subsystem +============= + +To change the configuration parameters of a running metadata server, run the +following command: + +.. prompt:: bash $ + + ceph tell mds.{mds-id} config set {setting} {value} + +Example: + +.. prompt:: bash $ + + ceph tell mds.0 config set debug_ms 1 + +To enable debug messages, run the following command: + +.. prompt:: bash $ + + ceph mds stat + +To display the status of all metadata servers, run the following command: + +.. prompt:: bash $ + + ceph mds fail 0 + +To mark the active metadata server as failed (and to trigger failover to a +standby if a standby is present), run the following command: + +.. todo:: ``ceph mds`` subcommands missing docs: set, dump, getmap, stop, setmap + + +Mon Subsystem +============= + +To display monitor statistics, run the following command: + +.. prompt:: bash $ + + ceph mon stat + +This command returns output similar to the following: + +:: + + e2: 3 mons at {a=127.0.0.1:40000/0,b=127.0.0.1:40001/0,c=127.0.0.1:40002/0}, election epoch 6, quorum 0,1,2 a,b,c + +There is a ``quorum`` list at the end of the output. It lists those monitor +nodes that are part of the current quorum. + +To retrieve this information in a more direct way, run the following command: + +.. prompt:: bash $ + + ceph quorum_status -f json-pretty + +This command returns output similar to the following: + +.. code-block:: javascript + + { + "election_epoch": 6, + "quorum": [ + 0, + 1, + 2 + ], + "quorum_names": [ + "a", + "b", + "c" + ], + "quorum_leader_name": "a", + "monmap": { + "epoch": 2, + "fsid": "ba807e74-b64f-4b72-b43f-597dfe60ddbc", + "modified": "2016-12-26 14:42:09.288066", + "created": "2016-12-26 14:42:03.573585", + "features": { + "persistent": [ + "kraken" + ], + "optional": [] + }, + "mons": [ + { + "rank": 0, + "name": "a", + "addr": "127.0.0.1:40000\/0", + "public_addr": "127.0.0.1:40000\/0" + }, + { + "rank": 1, + "name": "b", + "addr": "127.0.0.1:40001\/0", + "public_addr": "127.0.0.1:40001\/0" + }, + { + "rank": 2, + "name": "c", + "addr": "127.0.0.1:40002\/0", + "public_addr": "127.0.0.1:40002\/0" + } + ] + } + } + + +The above will block until a quorum is reached. + +To see the status of a specific monitor, run the following command: + +.. prompt:: bash $ + + ceph tell mon.[name] mon_status + +Here the value of ``[name]`` can be found by consulting the output of the +``ceph quorum_status`` command. This command returns output similar to the +following: + +:: + + { + "name": "b", + "rank": 1, + "state": "peon", + "election_epoch": 6, + "quorum": [ + 0, + 1, + 2 + ], + "features": { + "required_con": "9025616074522624", + "required_mon": [ + "kraken" + ], + "quorum_con": "1152921504336314367", + "quorum_mon": [ + "kraken" + ] + }, + "outside_quorum": [], + "extra_probe_peers": [], + "sync_provider": [], + "monmap": { + "epoch": 2, + "fsid": "ba807e74-b64f-4b72-b43f-597dfe60ddbc", + "modified": "2016-12-26 14:42:09.288066", + "created": "2016-12-26 14:42:03.573585", + "features": { + "persistent": [ + "kraken" + ], + "optional": [] + }, + "mons": [ + { + "rank": 0, + "name": "a", + "addr": "127.0.0.1:40000\/0", + "public_addr": "127.0.0.1:40000\/0" + }, + { + "rank": 1, + "name": "b", + "addr": "127.0.0.1:40001\/0", + "public_addr": "127.0.0.1:40001\/0" + }, + { + "rank": 2, + "name": "c", + "addr": "127.0.0.1:40002\/0", + "public_addr": "127.0.0.1:40002\/0" + } + ] + } + } + +To see a dump of the monitor state, run the following command: + +.. prompt:: bash $ + + ceph mon dump + +This command returns output similar to the following: + +:: + + dumped monmap epoch 2 + epoch 2 + fsid ba807e74-b64f-4b72-b43f-597dfe60ddbc + last_changed 2016-12-26 14:42:09.288066 + created 2016-12-26 14:42:03.573585 + 0: 127.0.0.1:40000/0 mon.a + 1: 127.0.0.1:40001/0 mon.b + 2: 127.0.0.1:40002/0 mon.c |