ceph/doc/rados/deployment/ceph-deploy-osd.rst

   1 =================
   2  Add/Remove OSDs
   3 =================
   4
   5 Adding and removing Ceph OSD Daemons to your cluster may involve a few more
   6 steps when compared to adding and removing other Ceph daemons. Ceph OSD Daemons
   7 write data to the disk and to journals. So you need to provide a disk for the
   8 OSD and a path to the journal partition (i.e., this is the most common
   9 configuration, but you may configure your system to  your own needs).
  10
  11 In Ceph v0.60 and later releases, Ceph supports ``dm-crypt`` on disk encryption.
  12 You may specify the ``--dmcrypt`` argument when preparing an OSD to tell
  13 ``ceph-deploy`` that you want to use encryption. You may also specify the
  14 ``--dmcrypt-key-dir`` argument to specify the location of ``dm-crypt``
  15 encryption keys.
  16
  17 You should test various drive configurations to gauge their throughput before
  18 before building out a large cluster. See `Data Storage`_ for additional details.
  19
  20
  21 List Disks
  22 ==========
  23
  24 To list the disks on a node, execute the following command::
  25
  26         ceph-deploy disk list {node-name [node-name]...}
  27
  28
  29 Zap Disks
  30 =========
  31
  32 To zap a disk (delete its partition table) in preparation for use with Ceph,
  33 execute the following::
  34
  35         ceph-deploy disk zap {osd-server-name} {disk-name}
  36         ceph-deploy disk zap osdserver1 /dev/sdb /dev/sdc
  37
  38 .. important:: This will delete all data.
  39
  40
  41 Create OSDs
  42 ===========
  43
  44 Once you create a cluster, install Ceph packages, and gather keys, you
  45 may create the OSDs and deploy them to the OSD node(s). If you need to
  46 identify a disk or zap it prior to preparing it for use as an OSD,
  47 see `List Disks`_ and `Zap Disks`_. ::
  48
  49         ceph-deploy osd create --data {data-disk} {node-name}
  50
  51 For example::
  52
  53         ceph-deploy osd create --data /dev/ssd osd-server1
  54
  55 For bluestore (the default) the example assumes a disk dedicated to one Ceph
  56 OSD Daemon. Filestore is also supported, in which case a ``--journal`` flag in
  57 addition to ``--filestore`` needs to be used to define the Journal device on
  58 the remote host.
  59
  60 .. note:: When running multiple Ceph OSD daemons on a single node, and
  61    sharing a partioned journal with each OSD daemon, you should consider
  62    the entire node the minimum failure domain for CRUSH purposes, because
  63    if the SSD drive fails, all of the Ceph OSD daemons that journal to it
  64    will fail too.
  65
  66
  67 List OSDs
  68 =========
  69
  70 To list the OSDs deployed on a node(s), execute the following command::
  71
  72  ceph-deploy osd list {node-name}
  73
  74
  75 Destroy OSDs
  76 ============
  77
  78 .. note:: Coming soon. See `Remove OSDs`_ for manual procedures.
  79
  80 .. To destroy an OSD, execute the following command::
  81
  82 ..      ceph-deploy osd destroy {node-name}:{path-to-disk}[:{path/to/journal}]
  83
  84 .. Destroying an OSD will take it ``down`` and ``out`` of the cluster.
  85
  86 .. _Data Storage: ../../../start/hardware-recommendations#data-storage
  87 .. _Remove OSDs: ../../operations/add-or-rm-osds#removing-osds-manual