ceph/PendingReleaseNotes

>= 12.0.0
------
* The "journaler allow split entries" config setting has been removed.
* The 'apply' mode of cephfs-journal-tool has been removed

12.0.0
------

 * When assigning a network to the public network and not to
   the cluster network the network specification of the public
   network will be used for the cluster network as well.
   In older versions this would lead to cluster services
   being bound to 0.0.0.0:<port>, thus making the
   cluster service even more publicly available than the
   public services. When only specifying a cluster network it
   will still result in the public services binding to 0.0.0.0.

*  Some variants of the omap_get_keys and omap_get_vals librados
   functions have been deprecated in favor of omap_get_vals2 and
   omap_get_keys2.  The new methods include an output argument
   indicating whether there are additional keys left to fetch.
   Previously this had to be inferred from the requested key count vs
   the number of keys returned, but this breaks with new OSD-side
   limits on the number of keys or bytes that can be returned by a
   single omap request.  These limits were introduced by kraken but
   are effectively disabled by default (by setting a very large limit
   of 1 GB) because users of the newly deprecated interface cannot
   tell whether they should fetch more keys or not.  In the case of
   the standalone calls in the C++ interface
   (IoCtx::get_omap_{keys,vals}), librados has been updated to loop on
   the client side to provide a correct result via multiple calls to
   the OSD.  In the case of the methods used for building
   multi-operation transactions, however, client-side looping is not
   practical, and the methods have been deprecated.  Note that use of
   either the IoCtx methods on older librados versions or the
   deprecated methods on any version of librados will lead to
   incomplete results if/when the new OSD limits are enabled.

* In previous versions, if a client sent an op to the wrong OSD, the OSD
  would reply with ENXIO.  The rationale here is that the client or OSD is
  clearly buggy and we want to surface the error as clearly as possible.
  We now only send the ENXIO reply if the osd_enxio_on_misdirected_op option
  is enabled (it's off by default).  This means that a VM using librbd that
  previously would have gotten an EIO and gone read-only will now see a
  blocked/hung IO instead.

*  When configuring ceph-fuse mounts in /etc/fstab, a new syntax is
   available that uses "ceph.<arg>=<val>" in the options column, instead
   of putting configuration in the device column.  The old style syntax
   still works.  See the documentation page "Mount CephFS in your
   file systems table" for details.

12.0.1
------

* The original librados rados_objects_list_open (C) and objects_begin
  (C++) object listing API, deprecated in Hammer, has finally been
  removed.  Users of this interface must update their software to use
  either the rados_nobjects_list_open (C) and nobjects_begin (C++) API or
  the new rados_object_list_begin (C) and object_list_begin (C++) API
  before updating the client-side librados library to Luminous.

  Object enumeration (via any API) with the latest librados version
  and pre-Hammer OSDs is no longer supported.  Note that no in-tree
  Ceph services rely on object enumeration via the deprecated APIs, so
  only external librados users might be affected.

  The newest (and recommended) rados_object_list_begin (C) and
  object_list_begin (C++) API is only usable on clusters with the
  SORTBITWISE flag enabled (Jewel and later).  (Note that this flag is
  required to be set before upgrading beyond Jewel.)

* The rados copy-get-classic operation has been removed since it has not been
  used by the OSD since before hammer.  It is unlikely any librados user is
  using this operation explicitly since there is also the more modern copy-get.

* The RGW api for getting object torrent has changed its params from 'get_torrent'
  to 'torrent' so that it can be compatible with Amazon S3. Now the request for 
  object torrent is like 'GET /ObjectName?torrent'.

* The configuration option "osd pool erasure code stripe width" has
  been replaced by "osd pool erasure code stripe unit", and given the
  ability to be overridden by the erasure code profile setting
  "stripe_unit". For more details see "Erasure Code Profiles" in the
  documentation.

* rbd and cephfs can use erasure coding with bluestore. This may be
  enabled by setting 'allow_ec_overwrites' to 'true' for a pool. Since
  this relies on bluestore's checksumming to do deep scrubbing,
  enabling this on a pool stored on filestore is not allowed.

* The 'rados df' JSON output now prints numeric values as numbers instead of
  strings.

* There was a bug introduced in Jewel (#19119) that broke the mapping behavior
  when an "out" OSD that still existed in the CRUSH map was removed with 'osd rm'.
  This could result in 'misdirected op' and other errors.  The bug is now fixed,
  but the fix itself introduces the same risk because the behavior may vary between
  clients and OSDs.  To avoid problems, please ensure that all OSDs are removed
  from the CRUSH map before deleting them.  That is, be sure to do::

     ceph osd crush rm osd.123

  before::

     ceph osd rm osd.123

12.0.2
------

* The original librados rados_objects_list_open (C) and objects_begin
  (C++) object listing API, deprecated in Hammer, has finally been
  removed.  Users of this interface must update their software to use
  either the rados_nobjects_list_open (C) and nobjects_begin (C++) API or
  the new rados_object_list_begin (C) and object_list_begin (C++) API
  before updating the client-side librados library to Luminous.

  Object enumeration (via any API) with the latest librados version
  and pre-Hammer OSDs is no longer supported.  Note that no in-tree
  Ceph services rely on object enumeration via the deprecated APIs, so
  only external librados users might be affected.

  The newest (and recommended) rados_object_list_begin (C) and
  object_list_begin (C++) API is only usable on clusters with the
  SORTBITWISE flag enabled (Jewel and later).  (Note that this flag is
  required to be set before upgrading beyond Jewel.)
* CephFS clients without the 'p' flag in their authentication capability
  string will no longer be able to set quotas or any layout fields.  This
  flag previously only restricted modification of the pool and namespace
  fields in layouts.
* CephFS directory fragmentation (large directory support) is enabled
  by default on new filesystems.  To enable it on existing filesystems
  use "ceph fs set <fs_name> allow_dirfrags".
* CephFS will generate a health warning if you have fewer standby daemons
  than it thinks you wanted.  By default this will be 1 if you ever had
  a standby, and 0 if you did not.  You can customize this using
  ``ceph fs set <fs> standby_count_wanted <number>``.  Setting it
  to zero will effectively disable the health check.
* The "ceph mds tell ..." command has been removed.  It is superceded
  by "ceph tell mds.<id> ..."

12.1.0
------

* The ``mon_osd_max_op_age`` option has been renamed to
  ``mon_osd_warn_op_age`` (default: 32 seconds), to indicate we
  generate a warning at this age.  There is also a new
  ``mon_osd_err_op_age_ratio`` that is a expressed as a multitple of
  ``mon_osd_warn_op_age`` (default: 128, for roughly 60 minutes) to
  control when an error is generated.

* The default maximum size for a single RADOS object has been reduced from
  100GB to 128MB.  The 100GB limit was completely impractical in practice
  while the 128MB limit is a bit high but not unreasonable.  If you have an
  application written directly to librados that is using objects larger than
  128MB you may need to adjust ``osd_max_object_size``.

* The semantics of the 'rados ls' and librados object listing
  operations have always been a bit confusing in that "whiteout"
  objects (which logically don't exist and will return ENOENT if you
  try to access them) are included in the results.  Previously
  whiteouts only occurred in cache tier pools.  In luminous, logically
  deleted but snapshotted objects now result in a whiteout object, and
  as a result they will appear in 'rados ls' results, even though
  trying to read such an object will result in ENOENT.  The 'rados
  listsnaps' operation can be used in such a case to enumerate which
  snapshots are present.

  This may seem a bit strange, but is less strange than having a
  deleted-but-snapshotted object not appear at all and be completely
  hidden from librados's ability to enumerate objects.  Future
  versions of Ceph will likely include an alternative object
  enumeration interface that makes it more natural and efficient to
  enumerate all objects along with their snapshot and clone metadata.

* The deprecated 'crush_ruleset' property has finally been removed; please use
  'crush_rule' instead for the 'osd pool get ...' and 'osd pool set ..' commands.

* The 'osd pool default crush replicated ruleset' option has been
  removed and replaced by the 'osd pool default crush rule' option.
  By default it is -1, which means the mon will pick the first type
  replicated rule in the CRUSH map for replicated pools.  Erasure
  coded pools have rules that are automatically created for them if they are
  not specified at pool creation time.

* The `status` ceph-mgr module is enabled by default, and initially provides two
  commands: `ceph tell mgr osd status` and `ceph tell mgr fs status`.  These
  are high level colorized views to complement the existing CLI.