ceph/doc/mgr/administrator.rst

   1 .. _mgr-administrator-guide:
   2
   3 ceph-mgr administrator's guide
   4 ==============================
   5
   6 Manual setup
   7 ------------
   8
   9 Usually, you would set up a ceph-mgr daemon using a tool such
  10 as ceph-ansible.  These instructions describe how to set up
  11 a ceph-mgr daemon manually.
  12
  13 First, create an authentication key for your daemon::
  14
  15     ceph auth get-or-create mgr.$name mon 'allow profile mgr' osd 'allow *' mds 'allow *'
  16
  17 Place that key into ``mgr data`` path, which for a cluster "ceph"
  18 and mgr $name "foo" would be ``/var/lib/ceph/mgr/ceph-foo``.
  19
  20 Start the ceph-mgr daemon::
  21
  22     ceph-mgr -i $name
  23
  24 Check that the mgr has come up by looking at the output
  25 of ``ceph status``, which should now include a mgr status line::
  26
  27     mgr active: $name
  28
  29 Client authentication
  30 ---------------------
  31
  32 The manager is a new daemon which requires new CephX capabilities. If you upgrade
  33 a cluster from an old version of Ceph, or use the default install/deploy tools,
  34 your admin client should get this capability automatically. If you use tooling from
  35 elsewhere, you may get EACCES errors when invoking certain ceph cluster commands.
  36 To fix that, add a "mgr allow \*" stanza to your client's cephx capabilities by
  37 `Modifying User Capabilities`_.
  38
  39 High availability
  40 -----------------
  41
  42 In general, you should set up a ceph-mgr on each of the hosts
  43 running a ceph-mon daemon to achieve the same level of availability.
  44
  45 By default, whichever ceph-mgr instance comes up first will be made
  46 active by the monitors, and the others will be standbys.  There is
  47 no requirement for quorum among the ceph-mgr daemons.
  48
  49 If the active daemon fails to send a beacon to the monitors for
  50 more than ``mon mgr beacon grace`` (default 30s), then it will be replaced
  51 by a standby.
  52
  53 If you want to pre-empt failover, you can explicitly mark a ceph-mgr
  54 daemon as failed using ``ceph mgr fail <mgr name>``.
  55
  56 Calling module commands
  57 -----------------------
  58
  59 Where a module implements command line hooks, the commands will
  60 be accessible as ordinary Ceph commands::
  61
  62     ceph <command | help>
  63
  64 If you would like to see the list of commands handled by the
  65 manager (where normal ``ceph help`` would show all mon and mgr commands),
  66 you can send a command directly to the manager daemon::
  67
  68     ceph tell mgr help
  69
  70 Note that it is not necessary to address a particular mgr instance,
  71 simply ``mgr`` will pick the current active daemon.
  72
  73 Configuration
  74 -------------
  75
  76 OPTION(mgr_module_path, OPT_STR, CEPH_PKGLIBDIR "/mgr") // where to load python modules from
  77
  78 ``mgr module path``
  79
  80 :Description: Path to load modules from
  81 :Type: String
  82 :Default: ``"<library dir>/mgr"``
  83
  84 ``mgr data``
  85
  86 :Description: Path to load daemon data (such as keyring)
  87 :Type: String
  88 :Default: ``"/var/lib/ceph/mgr/$cluster-$id"``
  89
  90 ``mgr tick period``
  91
  92 :Description: How many seconds between mgr beacons to monitors, and other
  93               periodic checks.
  94 :Type: Integer
  95 :Default: ``5``
  96
  97 ``mon mgr beacon grace``
  98
  99 :Description: How long after last beacon should a mgr be considered failed
 100 :Type: Integer
 101 :Default: ``30``
 102
 103 .. _Modifying User Capabilities: ../../rados/operations/user-management/#modify-user-capabilities