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分类: LINUX
2016-04-02 20:16:51
This major release of Ceph will be the foundation for the next long-term stable release. There have been many major changes since the Infernalis (9.2.x) and Hammer (0.94.x) releases, and the upgrade process is non-trivial. Please read these release notes carefully.
There are a few known issues with this release candidate; see below.
Starting with Infernalis, we have dropped support for many older distributions so that we can move to a newer compiler toolchain (e.g., C++11). Although it is still possible to build Ceph on older distributions by installing backported development tools, we are not building and publishing release packages for ceph.com.
We now build packages for:
Upgrading directly from Firefly v0.80.z is not recommended. It is possible to do a direct upgrade, but not without downtime. We recommend that clusters are first upgraded to Hammer v0.94.6 or a later v0.94.z release; only then is it possible to upgrade to Jewel 10.2.z for an online upgrade (see below).
To do an offline upgrade directly from Firefly, all Firefly OSDs must be stopped and marked down before any Jewel OSDs will be allowed to start up. This fencing is enforced by the Jewel monitor, so use an upgrade procedure like:
Upgrade Ceph on monitor hosts
Restart all ceph-mon daemons
Upgrade Ceph on all OSD hosts
Stop all ceph-osd daemons
- Mark all OSDs down with something like::
ceph osd down seq 0 1000
Start all ceph-osd daemons
Upgrade and restart remaining daemons (ceph-mds, radosgw)
All cluster nodes must first upgrade to Hammer v0.94.4 or a later v0.94.z release; only then is it possible to upgrade to Jewel 10.2.z.
For all distributions that support systemd (CentOS 7, Fedora, Debian Jessie 8.x, OpenSUSE), ceph daemons are now managed using native systemd files instead of the legacy sysvinit scripts. For example,:
The main notable distro that is not yet using systemd is Ubuntu trusty 14.04. (The next Ubuntu LTS, 16.04, will use systemd instead of upstart.)
Ceph daemons now run as user and group ceph by default. The ceph user has a static UID assigned by Fedora and Debian (also used by derivative distributions like RHEL/CentOS and Ubuntu). On SUSE the ceph user will currently get a dynamically assigned UID when the user is created.
If your systems already have a ceph user, upgrading the package will cause problems. We suggest you first remove or rename the existing ‘ceph’ user and ‘ceph’ group before upgrading.
When upgrading, administrators have two options:
Add the following line to ceph.conf on all hosts:
This will make the Ceph daemons run as root (i.e., not drop privileges and switch to user ceph) if the daemon’s data directory is still owned by root. Newly deployed daemons will be created with data owned by user ceph and will run with reduced privileges, but upgraded daemons will continue to run as root.
Fix the data ownership during the upgrade. This is the preferred option, but it is more work and can be very time consuming. The process for each host is to:
Upgrade the ceph package. This creates the ceph user and group. For example:
Stop the daemon(s).:
Fix the ownership:
Restart the daemon(s).:
Alternatively, the same process can be done with a single daemon type, for example by stopping only monitors and chowning only /var/lib/ceph/mon.
The on-disk format for the experimental KeyValueStore OSD backend has changed. You will need to remove any OSDs using that backend before you upgrade any test clusters that use it.
When a pool quota is reached, librados operations now block indefinitely, the same way they do when the cluster fills up. (Previously they would return -ENOSPC). By default, a full cluster or pool will now block. If your librados application can handle ENOSPC or EDQUOT errors gracefully, you can get error returns instead by using the new librados OPERATION_FULL_TRY flag.
The return code for librbd’s rbd_aio_read and Image::aio_read API methods no longer returns the number of bytes read upon success. Instead, it returns 0 upon success and a negative value upon failure.
‘ceph scrub’, ‘ceph compact’ and ‘ceph sync force’ are now DEPRECATED. Users should instead use ‘ceph mon scrub’, ‘ceph mon compact’ and ‘ceph mon sync force’.
‘ceph mon_metadata’ should now be used as ‘ceph mon metadata’. There is no need to deprecate this command (same major release since it was first introduced).
The –dump-json option of “osdmaptool” is replaced by –dump json.
The commands of “pg ls-by-{pool,primary,osd}” and “pg ls” now take “recovering” instead of “recovery”, to include the recovering pgs in the listed pgs.
There are no major compatibility changes since Infernalis. Simply upgrading the daemons on each host and restarting all daemons is sufficient.
The rbd CLI no longer accepts the deprecated ‘–image-features’ option during create, import, and clone operations. The ‘–image-feature’ option should be used instead.
The rbd legacy image format (version 1) is deprecated with the Jewel release. Attempting to create a new version 1 RBD image will result in a warning. Future releases of Ceph will remove support for version 1 RBD images.
The ‘send_pg_creates’ and ‘map_pg_creates’ mon CLI commands are obsolete and no longer supported.
A new configure option ‘mon_election_timeout’ is added to specifically limit max waiting time of monitor election process, which was previously restricted by ‘mon_lease’.
CephFS filesystems created using versions older than Firefly (0.80) must use the new “cephfs-data-scan tmap_upgrade” command after upgrading to Jewel. See ‘Upgrading’ in the CephFS documentation for more information.
The ‘ceph mds setmap’ command has been removed.
The default RBD image features for new images have been updated to enable the following: exclusive lock, object map, fast-diff, and deep-flatten. These features are not currently supported by the RBD kernel driver nor older RBD clients. These features can be disabled on a per-image basis via the RBD CLI or the default features can be updated to the pre-Jewel setting by adding the following to the client section of the Ceph configuration file:
The rbd legacy image format (version 1) is deprecated with the Jewel release.