[[storage_cephfs]]
Ceph Filesystem (CephFS)
------------------------
ifdef::wiki[]
:pve-toplevel:
:title: Storage: CephFS
endif::wiki[]

Storage pool type: `cephfs`

CephFS implements a POSIX-compliant filesystem using a http://ceph.com[Ceph]
storage cluster to store its data. As CephFS builds on Ceph it shares most of
its properties, this includes redundancy, scalability, self healing and high
availability.

TIP: {pve} can xref:chapter_pveceph[manage ceph setups], which makes
configuring a CephFS storage easier. As recent hardware has plenty of CPU power
and RAM, running storage services and VMs on same node is possible without a
big performance impact.

To use the CephFS storage plugin you need update the debian stock Ceph client.
Add our Ceph repository xref:sysadmin_package_repositories_ceph[Ceph repository].
Once added, run an `apt update` and `apt dist-upgrade` cycle to get the newest
packages.

You need to make sure that there is no other Ceph repository configured,
otherwise the installation will fail or there will be mixed package
versions on the node, leading to unexpected behavior.

[[storage_cephfs_config]]
Configuration
~~~~~~~~~~~~~

This backend supports the common storage properties `nodes`,
`disable`, `content`, and the following `cephfs` specific properties:

monhost::

List of monitor daemon addresses. Optional, only needed if Ceph is not running
on the PVE cluster.

path::

The local mount point. Optional, defaults to `/mnt/pve/<STORAGE_ID>/`.

username::

Ceph user id. Optional, only needed if Ceph is not running on the PVE cluster
where it defaults to `admin`.

subdir::

CephFS subdirectory to mount. Optional, defaults to `/`.

fuse::

Access CephFS through FUSE, instead of the kernel client. Optional, defaults
to `0`.

.Configuration Example for a external Ceph cluster (`/etc/pve/storage.cfg`)
----
cephfs: cephfs-external
        monhost 10.1.1.20 10.1.1.21 10.1.1.22
        path /mnt/pve/cephfs-external
        content backup
        username admin
----
NOTE: Don't forget to setup the client secret key file if cephx was not turned
off.

Authentication
~~~~~~~~~~~~~~

If you use the, by-default enabled, `cephx` authentication, you need to copy
the secret from your external Ceph cluster to a Proxmox VE host.

Create the directory `/etc/pve/priv/ceph` with

 mkdir /etc/pve/priv/ceph

Then copy the secret

 scp cephfs.secret <proxmox>:/etc/pve/priv/ceph/<STORAGE_ID>.secret

The secret must be named to match your `<STORAGE_ID>`. Copying the
secret generally requires root privileges. The file must only contain the
secret key itself, opposed to the `rbd` backend which also contains a
`[client.userid]` section.

A secret can be received from the ceph cluster (as ceph admin) by issuing the
following command. Replace the `userid` with the actual client ID configured to
access the cluster. For further ceph user management see the Ceph docs
footnote:[Ceph user management http://docs.ceph.com/docs/luminous/rados/operations/user-management/].

 ceph auth get-key client.userid > cephfs.secret

If Ceph is installed locally on the PVE cluster, i.e., setup with `pveceph`,
this is done automatically.

Storage Features
~~~~~~~~~~~~~~~~

The `cephfs` backend is a POSIX-compliant filesystem on top of a Ceph cluster.

.Storage features for backend `cephfs`
[width="100%",cols="m,m,3*d",options="header"]
|==============================================================================
|Content types              |Image formats  |Shared |Snapshots |Clones
|vztmpl iso backup snippets |none           |yes    |yes^[1]^  |no
|==============================================================================
^[1]^ Snapshots, while no known bugs, cannot be guaranteed to be stable yet, as
they lack testing.

ifdef::wiki[]

See Also
~~~~~~~~

* link:/wiki/Storage[Storage]

endif::wiki[]

