Learn Proxmox VE - Backup & Restore Strategy (vzdump & Proxmox Backup Server)

#Introduction

All the greatness of your infrastructure — cluster, HA, distributed storage — is meaningless if data can't be recovered after a disaster. Backup isn't an add-on; it's a primary operational requirement. Episode 11 teaches you the right backup strategy in Proxmox.

We'll master vzdump as the built-in backup tool, understand the available backup modes, schedule automatic backups, and then get to know Proxmox Backup Server (PBS) as an enterprise-class backup solution with incremental backups and deduplication.

#Backup with vzdump

#Backup Modes

vzdump is Proxmox's built-in backup tool for VMs and containers. It supports three modes:

• Snapshot: creates an instant snapshot, then backs up from the snapshot — the VM keeps running with zero downtime. The default and most recommended mode.
• Suspend: pauses the VM briefly during the backup process, then resumes it. Useful for ensuring full consistency without taking a snapshot.
• Stop: powers the VM off during the backup. The most consistent, but causes downtime.

snapshot : no downtime, default
suspend  : brief pause, full consistency
stop     : downtime, most consistent

For the majority of workloads, snapshot mode is the right choice.

#Backup Formats

The backup output is stored in two formats:

• .vma: Proxmox's archive format for VMs — stores the entire virtual disk with metadata.
• .tar: the archive format for LXC containers — contains the container's entire rootfs.

vzdump 100 --mode snapshot --compress zstd

The vzdump 100 --mode snapshot --compress zstd command backs up VM 100 in snapshot mode with zstd compression. The result is stored on a storage that supports the backup content type, usually /var/lib/vz/dump/.

#Scheduling a Backup Job via the UI

Manual backups aren't enough for serious operations. In the web UI, open Datacenter -> Backup -> Add to create a backup job: choose the VMs or containers to back up, the destination storage, the schedule (e.g. every night at 02.00), retention, and mode. Proxmox will run it automatically according to the schedule.

#Restoring from a Backup

#The Restore Procedure

Restore is the opposite of backup — and it's tested less often, so many teams forget how to do it. In Proxmox, restore can be done from the Backups tab on the storage, or via the CLI:

qmrestore /var/lib/vz/dump/vzdump-qemu-100-2026_08_10-02_00_00.vma.zst 100

The qmrestore command restores VM 100 to the state at backup time. Make sure the target VM isn't running, or use a new VM ID to restore as a copy.

#Retention and Backup Strategy

#Defining a Retention Policy

Keeping backups forever isn't a solution — storage is limited and costs balloon. Set a retention policy: how many backups to keep per interval.

• Keep daily backups for 7 days.
• Keep weekly backups for 4 weeks.
• Keep monthly backups for 12 months.

Proxmox supports retention with the keep-last, keep-daily, keep-weekly, and keep-monthly parameters on backup jobs.

keep-last 3, keep-daily 7, keep-weekly 4, keep-monthly 12

This combination maintains several recovery points without exhausting storage.

#Testing Restores Periodically

A backup that's never tested is a hope, not a guarantee. Schedule periodic restore tests: restore a VM to a sandbox, verify the services run, then delete it. This action is more valuable than adding more backup capacity itself.

#Proxmox Backup Server (PBS)

#A Dedicated Backup Appliance

Proxmox Backup Server is a dedicated application (installable as its own ISO) built for large-scale backups. Unlike regular backups that store complete files each time, PBS stores data in a very efficient way.

#PBS Standout Features

• Incremental backup: after the first full backup, subsequent backups only store the changes — dramatically saving storage.
• Deduplication: identical data (e.g. duplicate files across many VMs) is stored only once.
• Encryption: backups can be encrypted on the client side, so data stays safe even if the backup server is stolen.
• Verification jobs: PBS can check backups periodically to ensure data can be recovered.

Proxmox -> (encrypt) -> PBS -> (dedup) -> storage

Adding PBS as a Proxmox storage is as easy as adding any other storage: Datacenter -> Storage -> Add -> Proxmox Backup Server, fill in the server address, datastore, and credentials.

#Closing

Episode 11 equipped you with the right backup strategy: using vzdump with snapshot mode, understanding the VMA and tar formats, scheduling backup jobs, restoring VMs with qmrestore, and leveraging PBS for incremental backups with encryption and deduplication.

The key takeaways:

• Snapshot mode is the default with no downtime; stop is most consistent but has downtime.
• Backup formats: .vma for VMs, .tar for containers.
• Scheduled backup jobs guarantee consistency without relying on human memory.
• Restores must be tested regularly, not just after a disaster.
• PBS saves storage through incremental backups and deduplication.
• Use PBS encryption and follow the 3-2-1 principle.

In the next episode, episode 12, we will cover storage replication and VM migration — replicating VM data between nodes based on ZFS, then online migration with no downtime and offline migration, along with the requirements that must be met. Your backups are safe; now it's time to learn how to move workloads between nodes!