Proxmox Backup Server: first setup and first restore

Proxmox Backup Server (PBS) stores VM and container backups as deduplicated, optionally encrypted chunks, so a nightly backup of a 100 GB VM that changed 2 GB costs about 2 GB. Proxmox VE talks to it natively: once added as storage, every vzdump job, prune rule and restore button just works. This guide takes a fresh PBS to its first verified restore.

Before you start

• A separate machine or VM for PBS with its own disk for the datastore. Backups on the same hardware as the hypervisor do not count as a backup.
• Network access from the Proxmox VE hosts to the PBS on TCP port 8007.
• Root access to both systems.

Step 1: install PBS

Boot the PBS ISO and follow the installer, or install it on an existing Debian system with the official repository:

echo "deb http://download.proxmox.com/debian/pbs trixie pbs-no-subscription" | sudo tee /etc/apt/sources.list.d/pbs.list
sudo wget https://enterprise.proxmox.com/debian/proxmox-release-trixie.gpg -O /etc/apt/trusted.gpg.d/proxmox-release-trixie.gpg
sudo apt update
sudo apt install proxmox-backup-server

Replace trixie with your Debian codename (PBS 3 uses bookworm). The web interface is at https://pbs-host:8007; log in as root with realm Linux PAM.

Step 2: create a datastore

Format the backup disk, mount it, and create the datastore on it. In the GUI this is Datastore > Add Datastore; on the command line:

sudo proxmox-backup-manager disk list
sudo proxmox-backup-manager disk fs create store1 --disk sdb --filesystem ext4 --add-datastore true

This formats /dev/sdb, mounts it under /mnt/datastore/store1 and registers a datastore named store1 in one step. Careful: it erases everything on that disk. If the disk is already mounted, use proxmox-backup-manager datastore create store1 /mnt/datastore/store1 instead.

Step 3: a user for the hypervisor

Do not connect Proxmox VE with the PBS root account. Create a user in the pbs realm and give it the DatastoreBackup role on the datastore. That role can create and read backups but cannot delete them, which limits what a compromised hypervisor can do to your backup history.

sudo proxmox-backup-manager user create pve@pbs --password 'change-me'
sudo proxmox-backup-manager acl update /datastore/store1 DatastoreBackup --auth-id pve@pbs
sudo proxmox-backup-manager cert info | grep Fingerprint

Copy the fingerprint; Proxmox VE needs it to trust the self-signed certificate.

Step 4: add PBS as storage in Proxmox VE

On the PVE side, Datacenter > Storage > Add > Proxmox Backup Server: enter the PBS address, the datastore name, the user and password, and paste the fingerprint. The equivalent shell command:

pvesm add pbs pbs-store1 --server pbs.example.lan --datastore store1 --username pve@pbs --password 'change-me' --fingerprint 'AA:BB:CC:...'
pvesm status

If you tick Encryption on the storage, PVE generates a key and encrypts all backups client-side; the key is stored in /etc/pve/priv/storage/pbs-store1.enc. Download it and keep it somewhere safe: without that key the backups are unreadable, including by Proxmox staff.

Step 5: the first backup

vzdump 100 --storage pbs-store1 --mode snapshot --notes-template '{{guestname}}'
pvesm list pbs-store1

The second command lists the new backup as a volume such as pbs-store1:backup/vm/100/2026-10-14T02:30:00Z. In the PBS GUI the snapshot appears under Datastore > store1 > Content. Turn the one-off into a schedule in PVE under Datacenter > Backup > Add, and enable a Verify job on the PBS side so each snapshot is checked after it is written.

Step 6: prune and garbage collection

Pruning decides which snapshots to keep; garbage collection then frees the chunks no remaining snapshot references. Both are scheduled per datastore in the PBS GUI, or from the shell:

sudo proxmox-backup-manager prune-job create nightly --store store1 --schedule daily --keep-daily 7 --keep-weekly 4 --keep-monthly 6
sudo proxmox-backup-manager datastore update store1 --gc-schedule daily
sudo proxmox-backup-manager garbage-collection start store1

Careful: prune permanently removes snapshots outside the keep rules, and garbage collection permanently deletes their data. Check the result of a prune with --dry-run first: proxmox-backup-client prune vm/100 --repository pve@[email protected]:store1 --keep-daily 7 --dry-run. Garbage collection only deletes chunks that have been unreferenced for at least 24 hours and 5 minutes, so a prune followed by an immediate GC does not free space yet; that is by design.

Step 7: the first restore

Restore to a new VMID so the original stays untouched. In the PVE GUI select the storage, open Backups, choose the snapshot and press Restore, enter an unused VMID and a target storage. From the shell:

qmrestore pbs-store1:backup/vm/100/2026-10-14T02:30:00Z 9100 --storage local-lvm
qm start 9100

Boot it, log in, confirm the data is there, then destroy the copy with qm stop 9100 && qm destroy 9100. For a single file, select the snapshot in PVE and press File Restore; PVE starts a small helper VM that mounts the backup read-only and lets you browse and download individual files. If a restore does not succeed on a quiet afternoon, it will not succeed during an outage, so treat this step as part of the setup, not as optional.

Official documentation

• PBS: Installation
• PBS: Storage and datastores
• Proxmox VE: Backup and Restore