Install and Configure Proxmox Backup Server

This guide covers installing Proxmox Backup Server (PBS), creating a datastore, connecting it to your Proxmox VE cluster, and scheduling automated backups.

This guide implements the concept introduced in Chapter 2 — Backups.

What You'll Learn

• How to install PBS (dedicated hardware or as an LXC container)
• How to configure repositories and create a datastore
• How to create backup users and API tokens
• How to connect Proxmox VE to PBS
• How to schedule backup jobs and configure retention policies
• How to restore a VM or container from a backup

Prerequisites

• A machine, VM, or LXC container to run PBS (separate from your Proxmox VE nodes) that meets the system requirements
• A dedicated disk or partition for backup storage (separate from the OS disk)
• Network connectivity between PBS and your Proxmox VE nodes
• Root access to both PBS and Proxmox VE

Used Versions

Step-by-Step Implementation

1. Install PBS

PBS can run on dedicated hardware or as a virtualized instance. Choose the approach that fits your resources:

• Dedicated hardware (recommended for production): Install PBS from the official ISO on a separate physical machine. This gives the best isolation — a Proxmox VE node failure won't take your backups down with it.
• LXC container (good for small deployments): Run PBS inside a container on a Proxmox node. Simpler to set up, but your backups live on the same infrastructure they protect. Make sure the backup disk is physically separate.

Option A — Dedicated hardware (ISO install)

1. Download the latest Proxmox Backup Server ISO from the Proxmox downloads page.
2. Create a bootable USB drive using Rufus, Etcher, or dd:

   dd if=proxmox-backup-server_*.iso of=/dev/sdX bs=4M status=progress
   

3. Boot the target machine from the USB drive. Enter the BIOS if needed and set the USB as the first boot device.
4. The PBS installer will start. Click Install Proxmox Backup Server.
5. Select the target disk for the OS. All data on this disk will be erased.
6. Choose a filesystem:
   • ext4 — simple, reliable, single-disk setups
   • xfs — good for large files and high throughput
   • ZFS — choose this if you have multiple disks and want software RAID
7. Set your country, timezone, and keyboard layout.
8. Set the root password and an email address for notifications.
9. Configure the network:
   • Use a static IP address (strongly recommended)
   • Set the correct hostname, gateway, and DNS server
10. Review the summary and click Install.
11. After installation completes, remove the USB drive and reboot.

Option B — LXC container

If you prefer not to dedicate a physical machine, you can run PBS inside an LXC container using a community helper script.

1. SSH into your Proxmox VE node.
2. Run the helper script:

   bash -c "$(curl -fsSL https://raw.githubusercontent.com/community-scripts/ProxmoxVE/main/ct/proxmox-backup-server.sh)"
   

3. Follow the prompts to configure the container (CPU, RAM, storage, network).
4. The script will create and start the container with PBS pre-installed. Note the container ID (CTID) shown when it finishes (e.g., LXC Container 102 was successfully created.).
5. Enter the new PBS container from the Proxmox VE host:

   pct enter <CTID>
   

6. The helper script creates the container without a root password. Set one now — this is the password you will use to log into the PBS web interface:

   passwd root
   

7. Still inside the container, run the post-install script to optimize and configure PBS (it disables the enterprise repo, enables the no-subscription repo, and fixes the Debian sources):

   bash -c "$(curl -fsSL https://raw.githubusercontent.com/community-scripts/ProxmoxVE/main/tools/pve/post-pbs-install.sh)"
   

2. Access the web interface

1. Open a browser and navigate to:

   https://<PBS_IP>:8007
   

2. Accept the self-signed certificate warning.
3. Log in with:
   • Username: root
   • Password: the root password set during installation (for the LXC install, the one you set with passwd root in Step 1)
   • Realm: Linux PAM standard authentication

3. Configure package repositories

By default, PBS is configured to use the enterprise repository, which requires a paid subscription. For community use, switch to the no-subscription repository.

1. In the PBS web UI, navigate to Administration → Repositories.
2. Select the enterprise repository and click Disable.
3. Click Add and select the No-Subscription repository.
4. Click Add to enable it.

5. Update the package index:

   apt update && apt dist-upgrade -y
   

   Fixing missing GPG keys

   If you get a key error such as Failed to parse keyring "/usr/share/keyrings/proxmox-archive-keyring.gpg" during the update step, explicitly download the Proxmox key first:

   wget https://enterprise.proxmox.com/debian/proxmox-release-trixie.gpg -O /usr/share/keyrings/proxmox-archive-keyring.gpg
   

4. Create a datastore

A datastore is where PBS stores all backup data. It should point to a dedicated disk or mount point separate from the OS.

1. If your backup disk is not yet mounted, format and mount it:

   mkfs.ext4 /dev/sdb
   mkdir -p /mnt/backups
   mount /dev/sdb /mnt/backups
   

   Add it to /etc/fstab so it mounts on boot:

   echo '/dev/sdb /mnt/backups ext4 defaults 0 2' >> /etc/fstab
   

2. In the PBS web UI, navigate to Datastore → Add Datastore.
3. Fill in:
   • Name: e.g., community-backups
   • Backing Path: /mnt/backups
4. Click Add.

5. Create a backup user and API token

Avoid using the root account for automated backups. Create a dedicated user and API token.

Create the user:

1. Navigate to Configuration → Access Control → User Management.
2. Click Add.
3. Set:
   • User ID: backup
   • Password: a strong password
4. Click Add.

Assign permissions:

1. Navigate to Configuration → Access Control → Permissions.
2. Click Add → User Permission.
3. Set:
   • Path: /datastore/community-backups (or your datastore name)
   • User: backup@pbs
   • Role: DatastoreBackup
4. Click Add.

Create an API token:

1. Navigate to Configuration → Access Control → API Token.
2. Click Add.
3. Set:
   • User: backup@pbs
   • Token Name: e.g., pve-auto
4. Click Add.
5. Copy the token secret immediately — it is shown only once.

Assign permissions to the API token:

1. Navigate to Configuration → Access Control → Permissions.
2. Click Add → API Token Permission.
3. Set:
   • Path: /datastore/community-backups (or your datastore name)
   • API Token: backup@pbs!pve-auto
   • Role: DatastoreBackup
4. Click Add.

6. Connect Proxmox VE to PBS

On your Proxmox VE node, add the PBS as a storage backend.

1. Open the Proxmox VE web UI.
2. Navigate to Datacenter → Storage → Add → Proxmox Backup Server.
3. Fill in:
   • ID: e.g., pbs-community
   • Server: the PBS IP address
   • Datastore: community-backups (must match the datastore name on PBS)
   • Username: backup@pbs!pve-auto (user + token ID)
   • Password: paste the API token secret
   • Fingerprint: find this on the PBS web UI by navigating to Datastore → <Your Datastore> → Show Connection Information
4. Click Add.

7. Schedule backup jobs

1. In the Proxmox VE web UI, navigate to Datacenter → Backup → Add.
2. Configure the job:
   • Storage: select your PBS storage (e.g., pbs-community)
   • Schedule: e.g., daily at 02:00
   • Selection mode: choose All to back up everything, or Include selected VMs to pick specific ones
   • Mode: Snapshot (recommended — backs up VMs without stopping them)
   • Compression: ZSTD (good balance of speed and compression ratio)
3. Click Create.

8. Verify and restore from backups

Always test that you can restore from a backup. A backup you've never tested is a backup you can't trust.

Verify a backup:

1. In the Proxmox VE web UI, select a VM or container.
2. Go to Backup.
3. Select a backup entry and click Show Log to confirm it completed without errors.

Restore a backup:

1. Navigate to Datacenter → Storage → <your PBS storage> → Content.
2. Select the backup you want to restore.
3. Click Restore.
4. Choose the target node and storage for the restored VM/container.
5. Optionally change the VM ID to avoid conflicts with the original.
6. Click Restore and wait for completion.

9. Configure pruning and garbage collection

Over time, backups accumulate. Pruning removes old backups based on your retention policy. Garbage collection reclaims disk space from deduplicated chunks that are no longer referenced.

Set up pruning:

1. In the PBS web UI, navigate to Datastore → <your datastore> → Prune & GC → Prune Jobs → Add.
2. Set the retention policy:
   • Keep Last: 3
   • Keep Daily: 7
   • Keep Weekly: 4
   • Keep Monthly: 3
3. Set the schedule (e.g., daily).
4. Click Save.

Garbage collection runs automatically after pruning. You can also trigger it manually from the same page.

References

• Official Documentation: "Proxmox Backup Server Documentation" -- https://pbs.proxmox.com/docs/
• Official Documentation: "System Requirements" -- https://pbs.proxmox.com/docs/system-requirements.html
• Official Download Page: "Downloads" -- https://www.proxmox.com/en/downloads/category/proxmox-backup-server
• Community Script: "Proxmox Backup Server (PBS) Script" -- https://community-scripts.org/scripts/proxmox-backup-server
• Community Script: "PBS Post Install Script" -- https://community-scripts.org/scripts/post-pbs-install

Revision History