pve-storage-cephfs.adoc

   1 [[storage_cephfs]]
   2 Ceph Filesystem (CephFS)
   3 ------------------------
   4 ifdef::wiki[]
   5 :pve-toplevel:
   6 :title: Storage: CephFS
   7 endif::wiki[]
   8
   9 Storage pool type: `cephfs`
  10
  11 CephFS implements a POSIX-compliant filesystem, using a https://ceph.com[Ceph]
  12 storage cluster to store its data. As CephFS builds upon Ceph, it shares most of
  13 its properties. This includes redundancy, scalability, self-healing, and high
  14 availability.
  15
  16 TIP: {pve} can xref:chapter_pveceph[manage Ceph setups], which makes
  17 configuring a CephFS storage easier. As modern hardware offers a lot of
  18 processing power and RAM, running storage services and VMs on same node is
  19 possible without a significant performance impact.
  20
  21 To use the CephFS storage plugin, you must replace the stock Debian Ceph client,
  22 by adding our xref:sysadmin_package_repositories_ceph[Ceph repository].
  23 Once added, run `apt update`, followed by `apt dist-upgrade`, in order to get
  24 the newest packages.
  25
  26 WARNING: Please ensure that there are no other Ceph repositories configured.
  27 Otherwise the installation will fail or there will be mixed package versions on
  28 the node, leading to unexpected behavior.
  29
  30 [[storage_cephfs_config]]
  31 Configuration
  32 ~~~~~~~~~~~~~
  33
  34 This backend supports the common storage properties `nodes`,
  35 `disable`, `content`, as well as the following `cephfs` specific properties:
  36
  37 monhost::
  38
  39 List of monitor daemon addresses. Optional, only needed if Ceph is not running
  40 on the {pve} cluster.
  41
  42 path::
  43
  44 The local mount point. Optional, defaults to `/mnt/pve/<STORAGE_ID>/`.
  45
  46 username::
  47
  48 Ceph user id. Optional, only needed if Ceph is not running on the {pve} cluster,
  49 where it defaults to `admin`.
  50
  51 subdir::
  52
  53 CephFS subdirectory to mount. Optional, defaults to `/`.
  54
  55 fuse::
  56
  57 Access CephFS through FUSE, instead of the kernel client. Optional, defaults
  58 to `0`.
  59
  60 .Configuration example for an external Ceph cluster (`/etc/pve/storage.cfg`)
  61 ----
  62 cephfs: cephfs-external
  63         monhost 10.1.1.20 10.1.1.21 10.1.1.22
  64         path /mnt/pve/cephfs-external
  65         content backup
  66         username admin
  67 ----
  68 NOTE: Don't forget to set up the client's secret key file, if cephx was not
  69 disabled.
  70
  71 Authentication
  72 ~~~~~~~~~~~~~~
  73
  74 NOTE: If Ceph is installed locally on the {pve} cluster, the following is done
  75 automatically when adding the storage.
  76
  77 If you use `cephx` authentication, which is enabled by default, you need to
  78 provide the secret from the external Ceph cluster.
  79
  80 To configure the storage via the CLI, you first need to make the file
  81 containing the secret available. One way is to copy the file from the external
  82 Ceph cluster directly to one of the {pve} nodes. The following example will
  83 copy it to the `/root` directory of the node on which we run it:
  84
  85 ----
  86 # scp <external cephserver>:/etc/ceph/cephfs.secret /root/cephfs.secret
  87 ----
  88
  89 Then use the `pvesm` CLI tool to configure the external RBD storage, use the
  90 `--keyring` parameter, which needs to be a path to the secret file that you
  91 copied.  For example:
  92
  93 ----
  94 # pvesm add cephfs <name> --monhost "10.1.1.20 10.1.1.21 10.1.1.22" --content backup --keyring /root/cephfs.secret
  95 ----
  96
  97 When configuring an external RBD storage via the GUI, you can copy and paste
  98 the secret into the appropriate field.
  99
 100 The secret is only the key itself, as opposed to the `rbd` backend which also
 101 contains a `[client.userid]` section.
 102
 103 The secret will be stored at
 104
 105 ----
 106 # /etc/pve/priv/ceph/<STORAGE_ID>.secret
 107 ----
 108
 109 A secret can be received from the Ceph cluster (as Ceph admin) by issuing the
 110 command below, where `userid` is the client ID that has been configured to
 111 access the cluster. For further information on Ceph user management, see the
 112 Ceph docs.footnoteref:[cephusermgmt]
 113
 114 ----
 115 # ceph auth get-key client.userid > cephfs.secret
 116 ----
 117
 118 Storage Features
 119 ~~~~~~~~~~~~~~~~
 120
 121 The `cephfs` backend is a POSIX-compliant filesystem, on top of a Ceph cluster.
 122
 123 .Storage features for backend `cephfs`
 124 [width="100%",cols="m,m,3*d",options="header"]
 125 |==============================================================================
 126 |Content types              |Image formats  |Shared |Snapshots |Clones
 127 |vztmpl iso backup snippets |none           |yes    |yes^[1]^  |no
 128 |==============================================================================
 129 ^[1]^ While no known bugs exist, snapshots are not yet guaranteed to be stable,
 130 as they lack sufficient testing.
 131
 132 ifdef::wiki[]
 133
 134 See Also
 135 ~~~~~~~~
 136
 137 * link:/wiki/Storage[Storage]
 138
 139 endif::wiki[]
 140