ceph/doc/mgr/administrator.rst

95 lines
2.2 KiB
ReStructuredText

ceph-mgr administrator's guide
==============================
Setup
-----
Create an authentication key for your daemon:
::
ceph auth get-or-create mgr.$name mon 'allow *'
Place that key into ``mgr data`` path, which for a cluster "ceph"
and mgr $name "foo" would be ``/var/lib/ceph/mgr/ceph-foo``.
Start the ceph-mgr daemon:
::
ceph-mgr -i $name
Check that the mgr has come up by looking at the output
of ``ceph status``, which should now include a mgr status line:
::
mgr active: $name
High availability
-----------------
In general, you should set up a ceph-mgr on each of the hosts
running a ceph-mon daemon to achieve the same level of availability.
By default, whichever ceph-mgr instance comes up first will be made
active by the monitors, and the others will be standbys. There is
no requirement for quorum among the ceph-mgr daemons.
If the active daemon fails to send a beacon to the monitors for
more than ``mon mgr beacon grace`` (default 30s), then it will be replaced
by a standby.
If you want to pre-empt failover, you can explicitly mark a ceph-mgr
daemon as failed using ``ceph mgr fail <mgr name>``.
Calling module commands
-----------------------
Where a module implements command line hooks, using the Ceph CLI's
``tell`` command to call them like this:
::
ceph tell mgr <command | help>
Note that it is not necessary to address a particular mgr instance,
simply ``mgr`` will pick the current active daemon.
Use the ``help`` command to get a list of available commands from all
modules.
Configuration
-------------
OPTION(mgr_module_path, OPT_STR, CEPH_PKGLIBDIR "/mgr") // where to load python modules from
``mgr module path``
:Description: Path to load modules from
:Type: String
:Default: ``"<library dir>/mgr"``
``mgr modules``
:Description: List of python modules to load
:Type: String
:Default: ``"rest"`` (Load the REST API module only)
``mgr data``
:Description: Path to load daemon data (such as keyring)
:Type: String
:Default: ``"/var/lib/ceph/mgr/$cluster-$id"``
``mgr beacon period``
:Description: How many seconds between mgr beacons to monitors
:Type: Integer
:Default: ``5``
``mon mgr beacon grace``
:Description: How long after last beacon should a mgr be considered failed
:Type: Integer
:Default: ``30``