Part of the Proxmox Baremetal Journey series
I broke my install more times than I'd like to admit, but by the end I learned a ton about how PBS works under the hood. This post documents everything I learned while setting up Proxmox Backup Server to help others avoid my mistakes and establish production-level workflows.
Think of this as both a how-to guide and a "don't make my mistakes" story.
🔧 What Went Wrong (And How I Fixed It)
PBS is very strict about ownership and permissions. If they're wrong, nothing works. Here are the main traps I fell into:
Permission Issue #1 → The proxmox-backup directory was owned by root:root. PBS needs it owned by backup:backup.
Permission Issue #2 → I used 755 for the config directory. PBS requires 700.
Permission Issue #3 → My datastore subdirectories weren't owned by backup:backup. That blocked PBS from creating the crucial .chunks directory.
🛠 Clean Installation Guide
1. Update & Prepare System
sudo apt update && sudo apt upgrade -y
sudo apt install curl wget gnupg lsb-release apt-transport-https -y
2. Add the Proxmox Repository
echo "deb http://download.proxmox.com/debian/pbs bookworm pbs-no-subscription" | sudo tee /etc/apt/sources.list.d/pbs.list
wget -qO- http://download.proxmox.com/debian/proxmox-release-bookworm.gpg | sudo gpg --dearmor -o /etc/apt/trusted.gpg.d/proxmox-release-bookworm.gpg
3. Fix GPG Key Issues (if needed)
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 1140AF8F639E0C39
sudo apt update
4. Remove Old Packages (for a fresh reinstall)
sudo apt-get purge proxmox-backup proxmox-backup-client proxmox-backup-docs proxmox-backup-server -y
sudo apt-get purge proxmox-kernel-* proxmox-default-kernel -y
sudo rm -rf /etc/proxmox-backup /etc/systemd/system/proxmox-backup*
sudo rm -rf /mnt/pbs_backup/*
5. Install PBS
sudo apt install proxmox-backup-server -y
6. Create Datastore Directory
sudo mkdir -p /mnt/pbs_backup/datastore1
7. Fix Permissions
sudo chown -R backup:backup /mnt/pbs_backup/datastore1
sudo mkdir -p /etc/proxmox-backup
sudo chown -R backup:backup /etc/proxmox-backup
sudo chmod 700 /etc/proxmox-backup
sudo -u backup mkdir -p /mnt/pbs_backup/datastore1/.chunks
8. Start PBS Services
sudo systemctl start proxmox-backup
sudo systemctl enable proxmox-backup
sudo systemctl start proxmox-backup-proxy
sudo systemctl enable proxmox-backup-proxy
📘 Key Takeaways
Permissions are critical:
/etc/proxmox-backup → must be backup:backup with 700- Datastores → must be
backup:backup so PBS can create .chunks
Two services must run:
proxmox-backup → API serverproxmox-backup-proxy → Web interface
Troubleshooting Tips
If you encounter issues, check these common points:
Verify service status: sudo systemctl status proxmox-backup proxmox-backup-proxy
Check permissions: ls -la /etc/proxmox-backup and ls -la /mnt/pbs_backup/datastore1
Review logs: sudo journalctl -u proxmox-backup -f
Remember: when in doubt, proper permissions are usually the answer with PBS.
