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+=======================
+ Logging and Debugging
+=======================
+
+Typically, when you add debugging to your Ceph configuration, you do so at
+runtime. You can also add Ceph debug logging to your Ceph configuration file if
+you are encountering issues when starting your cluster. You may view Ceph log
+files under ``/var/log/ceph`` (the default location).
+
+.. tip:: When debug output slows down your system, the latency can hide
+ race conditions.
+
+Logging is resource intensive. If you are encountering a problem in a specific
+area of your cluster, enable logging for that area of the cluster. For example,
+if your OSDs are running fine, but your metadata servers are not, you should
+start by enabling debug logging for the specific metadata server instance(s)
+giving you trouble. Enable logging for each subsystem as needed.
+
+.. important:: Verbose logging can generate over 1GB of data per hour. If your
+ OS disk reaches its capacity, the node will stop working.
+
+If you enable or increase the rate of Ceph logging, ensure that you have
+sufficient disk space on your OS disk. See `Accelerating Log Rotation`_ for
+details on rotating log files. When your system is running well, remove
+unnecessary debugging settings to ensure your cluster runs optimally. Logging
+debug output messages is relatively slow, and a waste of resources when
+operating your cluster.
+
+See `Subsystem, Log and Debug Settings`_ for details on available settings.
+
+Runtime
+=======
+
+If you would like to see the configuration settings at runtime, you must log
+in to a host with a running daemon and execute the following::
+
+ ceph daemon {daemon-name} config show | less
+
+For example,::
+
+ ceph daemon osd.0 config show | less
+
+To activate Ceph's debugging output (*i.e.*, ``dout()``) at runtime, use the
+``ceph tell`` command to inject arguments into the runtime configuration::
+
+ ceph tell {daemon-type}.{daemon id or *} config set {name} {value}
+
+Replace ``{daemon-type}`` with one of ``osd``, ``mon`` or ``mds``. You may apply
+the runtime setting to all daemons of a particular type with ``*``, or specify
+a specific daemon's ID. For example, to increase
+debug logging for a ``ceph-osd`` daemon named ``osd.0``, execute the following::
+
+ ceph tell osd.0 config set debug_osd 0/5
+
+The ``ceph tell`` command goes through the monitors. If you cannot bind to the
+monitor, you can still make the change by logging into the host of the daemon
+whose configuration you'd like to change using ``ceph daemon``.
+For example::
+
+ sudo ceph daemon osd.0 config set debug_osd 0/5
+
+See `Subsystem, Log and Debug Settings`_ for details on available settings.
+
+
+Boot Time
+=========
+
+To activate Ceph's debugging output (*i.e.*, ``dout()``) at boot time, you must
+add settings to your Ceph configuration file. Subsystems common to each daemon
+may be set under ``[global]`` in your configuration file. Subsystems for
+particular daemons are set under the daemon section in your configuration file
+(*e.g.*, ``[mon]``, ``[osd]``, ``[mds]``). For example::
+
+ [global]
+ debug ms = 1/5
+
+ [mon]
+ debug mon = 20
+ debug paxos = 1/5
+ debug auth = 2
+
+ [osd]
+ debug osd = 1/5
+ debug filestore = 1/5
+ debug journal = 1
+ debug monc = 5/20
+
+ [mds]
+ debug mds = 1
+ debug mds balancer = 1
+
+
+See `Subsystem, Log and Debug Settings`_ for details.
+
+
+Accelerating Log Rotation
+=========================
+
+If your OS disk is relatively full, you can accelerate log rotation by modifying
+the Ceph log rotation file at ``/etc/logrotate.d/ceph``. Add a size setting
+after the rotation frequency to accelerate log rotation (via cronjob) if your
+logs exceed the size setting. For example, the default setting looks like
+this::
+
+ rotate 7
+ weekly
+ compress
+ sharedscripts
+
+Modify it by adding a ``size`` setting. ::
+
+ rotate 7
+ weekly
+ size 500M
+ compress
+ sharedscripts
+
+Then, start the crontab editor for your user space. ::
+
+ crontab -e
+
+Finally, add an entry to check the ``etc/logrotate.d/ceph`` file. ::
+
+ 30 * * * * /usr/sbin/logrotate /etc/logrotate.d/ceph >/dev/null 2>&1
+
+The preceding example checks the ``etc/logrotate.d/ceph`` file every 30 minutes.
+
+
+Valgrind
+========
+
+Debugging may also require you to track down memory and threading issues.
+You can run a single daemon, a type of daemon, or the whole cluster with
+Valgrind. You should only use Valgrind when developing or debugging Ceph.
+Valgrind is computationally expensive, and will slow down your system otherwise.
+Valgrind messages are logged to ``stderr``.
+
+
+Subsystem, Log and Debug Settings
+=================================
+
+In most cases, you will enable debug logging output via subsystems.
+
+Ceph Subsystems
+---------------
+
+Each subsystem has a logging level for its output logs, and for its logs
+in-memory. You may set different values for each of these subsystems by setting
+a log file level and a memory level for debug logging. Ceph's logging levels
+operate on a scale of ``1`` to ``20``, where ``1`` is terse and ``20`` is
+verbose [#]_ . In general, the logs in-memory are not sent to the output log unless:
+
+- a fatal signal is raised or
+- an ``assert`` in source code is triggered or
+- upon requested. Please consult `document on admin socket <http://docs.ceph.com/en/latest/man/8/ceph/#daemon>`_ for more details.
+
+A debug logging setting can take a single value for the log level and the
+memory level, which sets them both as the same value. For example, if you
+specify ``debug ms = 5``, Ceph will treat it as a log level and a memory level
+of ``5``. You may also specify them separately. The first setting is the log
+level, and the second setting is the memory level. You must separate them with
+a forward slash (/). For example, if you want to set the ``ms`` subsystem's
+debug logging level to ``1`` and its memory level to ``5``, you would specify it
+as ``debug ms = 1/5``. For example:
+
+
+
+.. code-block:: ini
+
+ debug {subsystem} = {log-level}/{memory-level}
+ #for example
+ debug mds balancer = 1/20
+
+
+The following table provides a list of Ceph subsystems and their default log and
+memory levels. Once you complete your logging efforts, restore the subsystems
+to their default level or to a level suitable for normal operations.
+
+
++--------------------+-----------+--------------+
+| Subsystem | Log Level | Memory Level |
++====================+===========+==============+
+| ``default`` | 0 | 5 |
++--------------------+-----------+--------------+
+| ``lockdep`` | 0 | 1 |
++--------------------+-----------+--------------+
+| ``context`` | 0 | 1 |
++--------------------+-----------+--------------+
+| ``crush`` | 1 | 1 |
++--------------------+-----------+--------------+
+| ``mds`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``mds balancer`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``mds locker`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``mds log`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``mds log expire`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``mds migrator`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``buffer`` | 0 | 1 |
++--------------------+-----------+--------------+
+| ``timer`` | 0 | 1 |
++--------------------+-----------+--------------+
+| ``filer`` | 0 | 1 |
++--------------------+-----------+--------------+
+| ``striper`` | 0 | 1 |
++--------------------+-----------+--------------+
+| ``objecter`` | 0 | 1 |
++--------------------+-----------+--------------+
+| ``rados`` | 0 | 5 |
++--------------------+-----------+--------------+
+| ``rbd`` | 0 | 5 |
++--------------------+-----------+--------------+
+| ``rbd mirror`` | 0 | 5 |
++--------------------+-----------+--------------+
+| ``rbd replay`` | 0 | 5 |
++--------------------+-----------+--------------+
+| ``journaler`` | 0 | 5 |
++--------------------+-----------+--------------+
+| ``objectcacher`` | 0 | 5 |
++--------------------+-----------+--------------+
+| ``client`` | 0 | 5 |
++--------------------+-----------+--------------+
+| ``osd`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``optracker`` | 0 | 5 |
++--------------------+-----------+--------------+
+| ``objclass`` | 0 | 5 |
++--------------------+-----------+--------------+
+| ``filestore`` | 1 | 3 |
++--------------------+-----------+--------------+
+| ``journal`` | 1 | 3 |
++--------------------+-----------+--------------+
+| ``ms`` | 0 | 5 |
++--------------------+-----------+--------------+
+| ``mon`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``monc`` | 0 | 10 |
++--------------------+-----------+--------------+
+| ``paxos`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``tp`` | 0 | 5 |
++--------------------+-----------+--------------+
+| ``auth`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``crypto`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``finisher`` | 1 | 1 |
++--------------------+-----------+--------------+
+| ``reserver`` | 1 | 1 |
++--------------------+-----------+--------------+
+| ``heartbeatmap`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``perfcounter`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``rgw`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``rgw sync`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``civetweb`` | 1 | 10 |
++--------------------+-----------+--------------+
+| ``javaclient`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``asok`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``throttle`` | 1 | 1 |
++--------------------+-----------+--------------+
+| ``refs`` | 0 | 0 |
++--------------------+-----------+--------------+
+| ``compressor`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``bluestore`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``bluefs`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``bdev`` | 1 | 3 |
++--------------------+-----------+--------------+
+| ``kstore`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``rocksdb`` | 4 | 5 |
++--------------------+-----------+--------------+
+| ``leveldb`` | 4 | 5 |
++--------------------+-----------+--------------+
+| ``memdb`` | 4 | 5 |
++--------------------+-----------+--------------+
+| ``fuse`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``mgr`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``mgrc`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``dpdk`` | 1 | 5 |
++--------------------+-----------+--------------+
+| ``eventtrace`` | 1 | 5 |
++--------------------+-----------+--------------+
+
+
+Logging Settings
+----------------
+
+Logging and debugging settings are not required in a Ceph configuration file,
+but you may override default settings as needed. Ceph supports the following
+settings:
+
+
+``log file``
+
+:Description: The location of the logging file for your cluster.
+:Type: String
+:Required: No
+:Default: ``/var/log/ceph/$cluster-$name.log``
+
+
+``log max new``
+
+:Description: The maximum number of new log files.
+:Type: Integer
+:Required: No
+:Default: ``1000``
+
+
+``log max recent``
+
+:Description: The maximum number of recent events to include in a log file.
+:Type: Integer
+:Required: No
+:Default: ``10000``
+
+
+``log to file``
+
+:Description: Determines if logging messages should appear in a file.
+:Type: Boolean
+:Required: No
+:Default: ``true``
+
+
+``log to stderr``
+
+:Description: Determines if logging messages should appear in ``stderr``.
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+
+``err to stderr``
+
+:Description: Determines if error messages should appear in ``stderr``.
+:Type: Boolean
+:Required: No
+:Default: ``true``
+
+
+``log to syslog``
+
+:Description: Determines if logging messages should appear in ``syslog``.
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+
+``err to syslog``
+
+:Description: Determines if error messages should appear in ``syslog``.
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+
+``log flush on exit``
+
+:Description: Determines if Ceph should flush the log files after exit.
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+
+``clog to monitors``
+
+:Description: Determines if ``clog`` messages should be sent to monitors.
+:Type: Boolean
+:Required: No
+:Default: ``true``
+
+
+``clog to syslog``
+
+:Description: Determines if ``clog`` messages should be sent to syslog.
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+
+``mon cluster log to syslog``
+
+:Description: Determines if the cluster log should be output to the syslog.
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+
+``mon cluster log file``
+
+:Description: The locations of the cluster's log files. There are two channels in
+ Ceph: ``cluster`` and ``audit``. This option represents a mapping
+ from channels to log files, where the log entries of that
+ channel are sent to. The ``default`` entry is a fallback
+ mapping for channels not explicitly specified. So, the following
+ default setting will send cluster log to ``$cluster.log``, and
+ send audit log to ``$cluster.audit.log``, where ``$cluster`` will
+ be replaced with the actual cluster name.
+:Type: String
+:Required: No
+:Default: ``default=/var/log/ceph/$cluster.$channel.log,cluster=/var/log/ceph/$cluster.log``
+
+
+
+OSD
+---
+
+
+``osd debug drop ping probability``
+
+:Description: ?
+:Type: Double
+:Required: No
+:Default: 0
+
+
+``osd debug drop ping duration``
+
+:Description:
+:Type: Integer
+:Required: No
+:Default: 0
+
+``osd debug drop pg create probability``
+
+:Description:
+:Type: Integer
+:Required: No
+:Default: 0
+
+``osd debug drop pg create duration``
+
+:Description: ?
+:Type: Double
+:Required: No
+:Default: 1
+
+
+``osd min pg log entries``
+
+:Description: The minimum number of log entries for placement groups.
+:Type: 32-bit Unsigned Integer
+:Required: No
+:Default: 250
+
+
+``osd op log threshold``
+
+:Description: How many op log messages to show up in one pass.
+:Type: Integer
+:Required: No
+:Default: 5
+
+
+
+Filestore
+---------
+
+``filestore debug omap check``
+
+:Description: Debugging check on synchronization. This is an expensive operation.
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+
+MDS
+---
+
+
+``mds debug scatterstat``
+
+:Description: Ceph will assert that various recursive stat invariants are true
+ (for developers only).
+
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+
+``mds debug frag``
+
+:Description: Ceph will verify directory fragmentation invariants when
+ convenient (developers only).
+
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+
+``mds debug auth pins``
+
+:Description: The debug auth pin invariants (for developers only).
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+
+``mds debug subtrees``
+
+:Description: The debug subtree invariants (for developers only).
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+
+
+RADOS Gateway
+-------------
+
+
+``rgw log nonexistent bucket``
+
+:Description: Should we log a non-existent buckets?
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+
+``rgw log object name``
+
+:Description: Should an object's name be logged. // man date to see codes (a subset are supported)
+:Type: String
+:Required: No
+:Default: ``%Y-%m-%d-%H-%i-%n``
+
+
+``rgw log object name utc``
+
+:Description: Object log name contains UTC?
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+
+``rgw enable ops log``
+
+:Description: Enables logging of every RGW operation.
+:Type: Boolean
+:Required: No
+:Default: ``true``
+
+
+``rgw enable usage log``
+
+:Description: Enable logging of RGW's bandwidth usage.
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+
+``rgw usage log flush threshold``
+
+:Description: Threshold to flush pending log data.
+:Type: Integer
+:Required: No
+:Default: ``1024``
+
+
+``rgw usage log tick interval``
+
+:Description: Flush pending log data every ``s`` seconds.
+:Type: Integer
+:Required: No
+:Default: 30
+
+
+``rgw intent log object name``
+
+:Description:
+:Type: String
+:Required: No
+:Default: ``%Y-%m-%d-%i-%n``
+
+
+``rgw intent log object name utc``
+
+:Description: Include a UTC timestamp in the intent log object name.
+:Type: Boolean
+:Required: No
+:Default: ``false``
+
+.. [#] there are levels >20 in some rare cases and that they are extremely verbose.
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-03 06:39:05 +0000