ceph/PendingReleaseNotes

>=16.0.0
--------
* mgr-pg_autoscaler: Autoscaler will now start out by scaling each
  pool to have a full complements of pgs from the start and will only
  decrease it when other pools need more pgs due to increased usage.
  This improves out of the box performance of Ceph by allowing more PGs 
  to be created for a given pool.

* New bluestore_rocksdb_options_annex config parameter. Complements
  bluestore_rocksdb_options and allows setting rocksdb options without repeating
  the existing defaults.
* The MDS in Pacific makes backwards-incompatible changes to the ON-RADOS
  metadata structures, which prevent a downgrade to older releases
  (to Octopus and older).

* $pid expansion in config paths like `admin_socket` will now properly expand
  to the daemon pid for commands like `ceph-mds` or `ceph-osd`. Previously only
  `ceph-fuse`/`rbd-nbd` expanded `$pid` with the actual daemon pid.

* The allowable options for some "radosgw-admin" commands have been changed.

  * "mdlog-list", "datalog-list", "sync-error-list" no longer accept
    start and end dates, but do accept a single optional start marker.
  * "mdlog-trim", "datalog-trim", "sync-error-trim" only accept a
    single marker giving the end of the trimmed range.
  * Similarly the date ranges and marker ranges have been removed on
    the RESTful DATALog and MDLog list and trim operations.

* ceph-volume: The ``lvm batch`` subcommand received a major rewrite. This 
  closed a number of bugs and improves usability in terms of size specification
  and calculation, as well as idempotency behaviour and disk replacement 
  process. Please refer to 
  https://docs.ceph.com/en/latest/ceph-volume/lvm/batch/ for more detailed 
  information.

* Configuration variables for permitted scrub times have changed.  The legal
  values for ``osd_scrub_begin_hour`` and ``osd_scrub_end_hour`` are ``0`` -
  ``23``. The use of 24 is now illegal. Specifying ``0`` for both values 
  causes every hour to be allowed.  The legal vaues for 
  ``osd_scrub_begin_week_day`` and ``osd_scrub_end_week_day`` are ``0`` - 
  ``6``. The use of ``7`` is now illegal. Specifying ``0`` for both values 
  causes every day of the week to be allowed.

* Support for multiple file systems in a single Ceph cluster is now stable. 
  New Ceph clusters enable support for multiple file systems by default.
  Existing clusters must still set the "enable_multiple" flag on the fs. 
  See the CephFS documentation for more information.

* volume/nfs: The "ganesha-" prefix from cluster id and nfs-ganesha common
  config object was removed to ensure a consistent namespace across different
  orchestrator backends. Delete any existing nfs-ganesha clusters prior
  to upgrading and redeploy new clusters after upgrading to Pacific.

* A new health check, DAEMON_OLD_VERSION, warns if different versions of
  Ceph are running on daemons. It generates a health error if multiple
  versions are detected.  This condition must exist for over 
  ``mon_warn_older_version_delay`` (set to 1 week by default) in order for the 
  health condition to be triggered. This allows most upgrades to proceed 
  without falsely seeing the warning.  If upgrade is paused for an extended 
  time period, health mute can be used like this "ceph health mute 
  DAEMON_OLD_VERSION --sticky". In this case after upgrade has finished use 
  "ceph health unmute DAEMON_OLD_VERSION".

* MGR: progress module can now be turned on/off, using these commands:
  ``ceph progress on`` and ``ceph progress off``.

* The ceph_volume_client.py library used for manipulating legacy "volumes" in
  CephFS is removed. All remaining users should use the "fs volume" interface
  exposed by the ceph-mgr:
  https://docs.ceph.com/en/latest/cephfs/fs-volumes/

* An AWS-compliant API: "GetTopicAttributes" was added to replace the existing 
  "GetTopic" API. The new API should be used to fetch information about topics 
  used for bucket notifications.

* librbd: The shared, read-only parent cache's config option 
  ``immutable_object_cache_watermark`` has now been updated to properly reflect 
  the upper cache utilization before space is reclaimed. The default 
  ``immutable_object_cache_watermark`` is now ``0.9``. If the capacity reaches 
  90% the daemon will delete cold cache.

* OSD: the option ``osd_fast_shutdown_notify_mon`` has been introduced to allow
  the OSD to notify the monitor it is shutting down even if ``osd_fast_shutdown``
  is enabled. This helps with the monitor logs on larger clusters, that may get
  many 'osd.X reported immediately failed by osd.Y' messages, and confuse tools.
* rgw/kms/vault: the transit logic has been revamped to better use
  the transit engine in vault.  To take advantage of this new
  functionality configuration changes are required.  See the current
  documentation (radosgw/vault) for more details.

* Scubs are more aggressive in trying to find more simultaneous possible PGs within osd_max_scrubs limitation.
  It is possible that increasing osd_scrub_sleep may be necessary to maintain client responsiveness.

>=15.0.0
--------

* MON: The cluster log now logs health detail every ``mon_health_to_clog_interval``,
  which has been changed from 1hr to 10min. Logging of health detail will be
  skipped if there is no change in health summary since last known.

* The ``ceph df`` command now lists the number of pgs in each pool.

* Monitors now have config option ``mon_allow_pool_size_one``, which is disabled
  by default. However, if enabled, user now have to pass the
  ``--yes-i-really-mean-it`` flag to ``osd pool set size 1``, if they are really
  sure of configuring pool size 1.

* librbd now inherits the stripe unit and count from its parent image upon creation.
  This can be overridden by specifying different stripe settings during clone creation.

* The balancer is now on by default in upmap mode. Since upmap mode requires
  ``require_min_compat_client`` luminous, new clusters will only support luminous
  and newer clients by default. Existing clusters can enable upmap support by running
  ``ceph osd set-require-min-compat-client luminous``. It is still possible to turn
  the balancer off using the ``ceph balancer off`` command. In earlier versions,
  the balancer was included in the ``always_on_modules`` list, but needed to be
  turned on explicitly using the ``ceph balancer on`` command.

* MGR: the "cloud" mode of the diskprediction module is not supported anymore
  and the ``ceph-mgr-diskprediction-cloud`` manager module has been removed. This
  is because the external cloud service run by ProphetStor is no longer accessible
  and there is no immediate replacement for it at this time. The "local" prediction
  mode will continue to be supported.

* Cephadm: There were a lot of small usability improvements and bug fixes:

  * Grafana when deployed by Cephadm now binds to all network interfaces.
  * ``cephadm check-host`` now prints all detected problems at once.
  * Cephadm now calls ``ceph dashboard set-grafana-api-ssl-verify false``
    when generating an SSL certificate for Grafana.
  * The Alertmanager is now correctly pointed to the Ceph Dashboard
  * ``cephadm adopt`` now supports adopting an Alertmanager
  * ``ceph orch ps`` now supports filtering by service name
  * ``ceph orch host ls`` now marks hosts as offline, if they are not
    accessible.

* Cephadm can now deploy NFS Ganesha services. For example, to deploy NFS with
  a service id of mynfs, that will use the RADOS pool nfs-ganesha and namespace
  nfs-ns::

    ceph orch apply nfs mynfs nfs-ganesha nfs-ns

* Cephadm: ``ceph orch ls --export`` now returns all service specifications in
  yaml representation that is consumable by ``ceph orch apply``. In addition,
  the commands ``orch ps`` and ``orch ls`` now support ``--format yaml`` and
  ``--format json-pretty``.

* CephFS: Automatic static subtree partitioning policies may now be configured
  using the new distributed and random ephemeral pinning extended attributes on
  directories. See the documentation for more information:
  https://docs.ceph.com/docs/master/cephfs/multimds/

* Cephadm: ``ceph orch apply osd`` supports a ``--preview`` flag that prints a preview of
  the OSD specification before deploying OSDs. This makes it possible to
  verify that the specification is correct, before applying it.

* RGW: The ``radosgw-admin`` sub-commands dealing with orphans --
  ``radosgw-admin orphans find``, ``radosgw-admin orphans finish``, and
  ``radosgw-admin orphans list-jobs`` -- have been deprecated. They have
  not been actively maintained and they store intermediate results on
  the cluster, which could fill a nearly-full cluster.  They have been
  replaced by a tool, currently considered experimental,
  ``rgw-orphan-list``.

* RBD: The name of the rbd pool object that is used to store
  rbd trash purge schedule is changed from "rbd_trash_trash_purge_schedule"
  to "rbd_trash_purge_schedule". Users that have already started using
  ``rbd trash purge schedule`` functionality and have per pool or namespace
  schedules configured should copy "rbd_trash_trash_purge_schedule"
  object to "rbd_trash_purge_schedule" before the upgrade and remove
  "rbd_trash_purge_schedule" using the following commands in every RBD
  pool and namespace where a trash purge schedule was previously
  configured::

    rados -p <pool-name> [-N namespace] cp rbd_trash_trash_purge_schedule rbd_trash_purge_schedule
    rados -p <pool-name> [-N namespace] rm rbd_trash_trash_purge_schedule

  or use any other convenient way to restore the schedule after the
  upgrade.

* librbd: The shared, read-only parent cache has been moved to a separate librbd
  plugin. If the parent cache was previously in-use, you must also instruct
  librbd to load the plugin by adding the following to your configuration::

    rbd_plugins = parent_cache

* Monitors now have a config option ``mon_osd_warn_num_repaired``, 10 by default.
  If any OSD has repaired more than this many I/O errors in stored data a
 ``OSD_TOO_MANY_REPAIRS`` health warning is generated.

* Introduce commands that manipulate required client features of a file system::

    ceph fs required_client_features <fs name> add <feature>
    ceph fs required_client_features <fs name> rm <feature>
    ceph fs feature ls

* OSD: A new configuration option ``osd_compact_on_start`` has been added which triggers
  an OSD compaction on start. Setting this option to ``true`` and restarting an OSD
  will result in an offline compaction of the OSD prior to booting.

* OSD: the option named ``bdev_nvme_retry_count`` has been removed. Because
  in SPDK v20.07, there is no easy access to bdev_nvme options, and this
  option is hardly used, so it was removed.

* Now when noscrub and/or nodeep-scrub flags are set globally or per pool,
  scheduled scrubs of the type disabled will be aborted. All user initiated
  scrubs are NOT interrupted.

* Alpine build related script, documentation and test have been removed since
  the most updated APKBUILD script of Ceph is already included by Alpine Linux's
  aports repository.

* fs: Names of new FSs, volumes, subvolumes and subvolume groups can only
  contain alphanumeric and ``-``, ``_`` and ``.`` characters. Some commands
  or CephX credentials may not work with old FSs with non-conformant names.

* It is now possible to specify the initial monitor to contact for Ceph tools
  and daemons using the ``mon_host_override`` config option or
  ``--mon-host-override <ip>`` command-line switch. This generally should only
  be used for debugging and only affects initial communication with Ceph's
  monitor cluster.

* `blacklist` has been replaced with `blocklist` throughout.  The following commands have changed:

  - ``ceph osd blacklist ...`` are now ``ceph osd blocklist ...``
  - ``ceph <tell|daemon> osd.<NNN> dump_blacklist`` is now ``ceph <tell|daemon> osd.<NNN> dump_blocklist``

* The following config options have changed:

  - ``mon osd blacklist default expire`` is now ``mon osd blocklist default expire``
  - ``mon mds blacklist interval`` is now ``mon mds blocklist interval``
  - ``mon mgr blacklist interval`` is now ''mon mgr blocklist interval``
  - ``rbd blacklist on break lock`` is now ``rbd blocklist on break lock``
  - ``rbd blacklist expire seconds`` is now ``rbd blocklist expire seconds``
  - ``mds session blacklist on timeout`` is now ``mds session blocklist on timeout``
  - ``mds session blacklist on evict`` is now ``mds session blocklist on evict``

* CephFS: Compatibility code for old on-disk format of snapshot has been removed.
  Current on-disk format of snapshot was introduced by Mimic release. If there
  are any snapshots created by Ceph release older than Mimic. Before upgrading,
  either delete them all or scrub the whole filesystem:

    ceph daemon <mds of rank 0> scrub_path / force recursive repair
    ceph daemon <mds of rank 0> scrub_path '~mdsdir' force recursive repair

* CephFS: Scrub is supported in multiple active mds setup. MDS rank 0 handles
  scrub commands, and forward scrub to other mds if necessary.

* The following librados API calls have changed:

  - ``rados_blacklist_add`` is now ``rados_blocklist_add``; the former will issue a deprecation warning and be removed in a future release.
  - ``rados.blacklist_add`` is now ``rados.blocklist_add`` in the C++ API.

* The JSON output for the following commands now shows ``blocklist`` instead of ``blacklist``:

  - ``ceph osd dump``
  - ``ceph <tell|daemon> osd.<N> dump_blocklist``

* caps: MON and MDS caps can now be used to restrict client's ability to view
  and operate on specific Ceph file systems. The FS can be specificed using
  ``fsname`` in caps. This also affects subcommand ``fs authorize``, the caps
  produce by it will be specific to the FS name passed in its arguments.

* fs: root_squash flag can be set in MDS caps. It disallows file system
  operations that need write access for clients with uid=0 or gid=0. This
  feature should prevent accidents such as an inadvertent `sudo rm -rf /<path>`.

* fs: "fs authorize" now sets MON cap to "allow <perm> fsname=<fsname>"
      instead of setting it to "allow r" all the time.

* ``ceph pg #.# list_unfound`` output has been enhanced to provide
  might_have_unfound information which indicates which OSDs may
  contain the unfound objects.

* The ``ceph orch apply rgw`` syntax and behavior have changed.  RGW
  services can now be arbitrarily named (it is no longer forced to be
  `realm.zone`).  The ``--rgw-realm=...`` and ``--rgw-zone=...``
  arguments are now optional, which means that if they are omitted, a
  vanilla single-cluster RGW will be deployed.  When the realm and
  zone are provided, the user is now responsible for setting up the
  multisite configuration beforehand--cephadm no longer attempts to
  create missing realms or zones.