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 Using modules
  57 -------------
  58
  59 Use the command ``ceph mgr module ls`` to see which modules are
  60 available, and which are currently enabled.  Enable or disable modules
  61 using the commands ``ceph mgr module enable <module>`` and
  62 ``ceph mgr module disable <module>`` respectively.
  63
  64 If a module is *enabled* then the active ceph-mgr daemon will load
  65 and execute it.  In the case of modules that provide a service,
  66 such as an HTTP server, the module may publish its address when it
  67 is loaded.  To see the addresses of such modules, use the command
  68 ``ceph mgr services``.
  69
  70 Some modules may also implement a special standby mode which runs on
  71 standby ceph-mgr daemons as well as the active daemon.  This enables
  72 modules that provide services to redirect their clients to the active
  73 daemon, if the client tries to connect to a standby.
  74
  75 Consult the documentation pages for individual manager modules for more
  76 information about what functionality each module provides.
  77
  78 Here is an example of enabling the :term:`Dashboard` module:
  79
  80 ::
  81
  82         $ ceph mgr module ls
  83         {
  84                 "enabled_modules": [
  85                         "restful",
  86                         "status"
  87                 ],
  88                 "disabled_modules": [
  89                         "dashboard"
  90                 ]
  91         }
  92
  93         $ ceph mgr module enable dashboard
  94         $ ceph mgr module ls
  95         {
  96                 "enabled_modules": [
  97                         "restful",
  98                         "status",
  99                         "dashboard"
 100                 ],
 101                 "disabled_modules": [
 102                 ]
 103         }
 104
 105         $ ceph mgr services
 106         {
 107                 "dashboard": "http://myserver.com:7789/",
 108                 "restful": "https://myserver.com:8789/"
 109         }
 110
 111
 112 The first time the cluster starts, it uses the ``mgr_initial_modules``
 113 setting to override which modules to enable.  However, this setting
 114 is ignored through the rest of the lifetime of the cluster: only
 115 use it for bootstrapping.  For example, before starting your
 116 monitor daemons for the first time, you might add a section like
 117 this to your ``ceph.conf``:
 118
 119 ::
 120
 121     [mon]
 122         mgr_initial_modules = dashboard balancer
 123
 124 Calling module commands
 125 -----------------------
 126
 127 Where a module implements command line hooks, the commands will
 128 be accessible as ordinary Ceph commands.  Ceph will automatically incorporate
 129 module commands into the standard CLI interface and route them appropriately to
 130 the module.::
 131
 132     ceph <command | help>
 133
 134 Configuration
 135 -------------
 136
 137 ``mgr_module_path``
 138
 139 :Description: Path to load modules from
 140 :Type: String
 141 :Default: ``"<library dir>/mgr"``
 142
 143 ``mgr_data``
 144
 145 :Description: Path to load daemon data (such as keyring)
 146 :Type: String
 147 :Default: ``"/var/lib/ceph/mgr/$cluster-$id"``
 148
 149 ``mgr_tick_period``
 150
 151 :Description: How many seconds between mgr beacons to monitors, and other
 152               periodic checks.
 153 :Type: Integer
 154 :Default: ``5``
 155
 156 ``mon_mgr_beacon_grace``
 157
 158 :Description: How long after last beacon should a mgr be considered failed
 159 :Type: Integer
 160 :Default: ``30``
 161
 162 .. _Modifying User Capabilities: ../../rados/operations/user-management/#modify-user-capabilities