[[storage_pbs]]
Proxmox Backup Server
---------------------
ifdef::wiki[]
:pve-toplevel:
:title: Storage: Proxmox Backup Server
endif::wiki[]

Storage pool type: `pbs`

This backend allows direct integration of a Proxmox Backup Server into {pve}
like any other storage.
A Proxmox Backup storage can be added directly through the {pve} API, CLI or
the web interface.

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

The backend supports all common storage properties, except the shared flag,
which is always set. Additionally, the following special properties to Proxmox
Backup Server are available:

server::

Server IP or DNS name. Required.

port::

Use this port instead of the default one, i.e. `8007`. Optional.

username::

The username for the Proxmox Backup Server storage. Required.

TIP: Do not forget to add the realm to the username. For example, `root@pam` or
`archiver@pbs`.

password::

The user password. The value will be saved in a file under
`/etc/pve/priv/storage/<STORAGE-ID>.pw` with access restricted to the root
user. Required.

datastore::

The ID of the Proxmox Backup Server datastore to use. Required.

fingerprint::

The fingerprint of the Proxmox Backup Server API TLS certificate. You can get
it in the Servers Dashboard or using the `proxmox-backup-manager cert info`
command. Required for self-signed certificates or any other one where the host
does not trusts the servers CA.

encryption-key::

A key to encrypt the backup data from the client side. Currently only
non-password protected (no key derive function (kdf)) are supported. Will be
saved in a file under `/etc/pve/priv/storage/<STORAGE-ID>.enc` with access
restricted to the root user.  Use the magic value `autogen` to automatically
generate a new one using `proxmox-backup-client key create --kdf none <path>`.
Optional.

master-pubkey::

A public RSA key used to encrypt the backup encryption key as part of the
backup task. Will be saved in a file under
`/etc/pve/priv/storage/<STORAGE-ID>.master.pem` with access restricted to the
root user.
The encrypted copy of the backup encryption key will be appended to each backup
and stored on the Proxmox Backup Server instance for recovery purposes.
Optional, requires `encryption-key`.

.Configuration Example (`/etc/pve/storage.cfg`)
----
pbs: backup
        datastore main
        server enya.proxmox.com
        content backup
        fingerprint 09:54:ef:..snip..:88:af:47:fe:4c:3b:cf:8b:26:88:0b:4e:3c:b2
        prune-backups keep-all=1
        username archiver@pbs
        encryption-key a9:ee:c8:02:13:..snip..:2d:53:2c:98
        master-pubkey 1
----

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

Proxmox Backup Server only supports backups, they can be block-level or
file-level based. {pve} uses block-level for virtual machines and file-level for
container.

.Storage features for backend `pbs`
[width="100%",cols="m,4*d",options="header"]
|===============================================================
|Content types |Image formats |Shared |Snapshots |Clones
|backup        |n/a           |yes    |n/a       |n/a
|===============================================================

[[storage_pbs_encryption]]
Encryption
~~~~~~~~~~

[thumbnail="screenshot/storage-pbs-encryption-with-key.png"]

Optionally, you can configure client-side encryption with AES-256 in GCM mode.
Encryption can be configured either via the web interface, or on the CLI with
the `encryption-key` option (see above). The key will be saved in the file
`/etc/pve/priv/storage/<STORAGE-ID>.enc`, which is only accessible by the root
user.

WARNING: Without their key, backups will be inaccessible. Thus, you should
keep keys ordered and in a place that is separate from the contents being
backed up. It can happen, for example, that you back up an entire system, using
a key on that system. If the system then becomes inaccessible for any reason
and needs to be restored, this will not be possible as the encryption key will be
lost along with the broken system.

It is recommended that you keep your key safe, but easily accessible, in
order for quick disaster recovery. For this reason, the best place to store it
is in your password manager, where it is immediately recoverable. As a backup to
this, you should also save the key to a USB flash drive and store that in a secure
place. This way, it is detached from any system, but is still easy to recover
from, in case of emergency. Finally, in preparation for the worst case scenario,
you should also consider keeping a paper copy of your key locked away in a safe
place. The `paperkey` subcommand can be used to create a QR encoded version of
your key. The following command sends the output of the `paperkey` command to
a text file, for easy printing.

----
# proxmox-backup-client key paperkey /etc/pve/priv/storage/<STORAGE-ID>.enc --output-format text > qrkey.txt
----

Additionally, it is possible to use a single RSA master key pair for key
recovery purposes: configure all clients doing encrypted backups to use a
single public master key, and all subsequent encrypted backups will contain a
RSA-encrypted copy of the used AES encryption key. The corresponding private
master key allows recovering the AES key and decrypting the backup even if the
client system is no longer available.

WARNING: The same safe-keeping rules apply to the master key pair as to the
regular encryption keys. Without a copy of the private key recovery is not
possible! The `paperkey` command supports generating paper copies of private
master keys for storage in a safe, physical location.

Because the encryption is managed on the client side, you can use the same
datastore on the server for unencrypted backups and encrypted backups, even
if they are encrypted with different keys. However, deduplication between
backups with different keys is not possible, so it is often better to create
separate datastores.

NOTE: Do not use encryption if there is no benefit from it, for example, when
you are running the server locally in a trusted network. It is always easier to
recover from unencrypted backups.

Example: Add Storage over CLI
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

// TODO: FIXME: add once available
//You can get a list of exported CIFS shares with:
//
//----
//# pvesm scan pbs <server> [--username <username>] [--password]
//----

Then you could add this share as a storage to the whole {pve} cluster
with:

----
# pvesm add pbs <id> --server <server> --datastore <datastore> --username <username> --fingerprint 00:B4:... --password
----

ifdef::wiki[]

See Also
~~~~~~~~

* link:/wiki/Storage[Storage]

endif::wiki[]
