storage: nfs cannot have subvolumes

[pve-docs.git] / pve-storage-nfs.adoc

NFS Backend
-----------
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:pve-toplevel:
:title: Storage: NFS
endif::wiki[]

Storage pool type: `nfs`

The NFS backend is based on the directory backend, so it shares most
properties. The directory layout and the file naming conventions are
the same. The main advantage is that you can directly configure the
NFS server properties, so the backend can mount the share
automatically. There is no need to modify `/etc/fstab`. The backend
can also test if the server is online, and provides a method to query
the server for exported shares.

Configuration
~~~~~~~~~~~~~

The backend supports all common storage properties, except the shared
flag, which is always set. Additionally, the following properties are
used to configure the NFS server:

server::

Server IP or DNS name. To avoid DNS lookup delays, it is usually
preferable to use an IP address instead of a DNS name - unless you
have a very reliable DNS server, or list the server in the local
`/etc/hosts` file.

export::

NFS export path (as listed by `pvesm nfsscan`).

You can also set NFS mount options:

path::

The local mount point (defaults to `/mnt/pve/<STORAGE_ID>/`).

options::

NFS mount options (see `man nfs`).

.Configuration Example (`/etc/pve/storage.cfg`)
----
nfs: iso-templates
	path /mnt/pve/iso-templates
	server 10.0.0.10
	export /space/iso-templates
	options vers=3,soft
	content iso,vztmpl
----

TIP: After an NFS request times out, NFS request are retried
indefinitely by default. This can lead to unexpected hangs on the
client side. For read-only content, it is worth to consider the NFS
`soft` option, which limits the number of retries to three.


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

NFS does not support snapshots, but the backend uses `qcow2` features
to implement snapshots and cloning.

.Storage features for backend `nfs`
[width="100%",cols="m,m,3*d",options="header"]
|==============================================================================
|Content types                     |Image formats  |Shared |Snapshots |Clones
|images rootdir vztmpl iso backup  |raw qcow2 vmdk |yes    |qcow2     |qcow2
|==============================================================================

Examples
~~~~~~~~

You can get a list of exported NFS shares with:

 # pvesm nfsscan <server>

ifdef::wiki[]

See Also
~~~~~~~~

* link:/wiki/Storage[Storage]

endif::wiki[]