Welcome, fellow homelab wizard! Let’s break down the (slightly extra) process of adding USB hard drives to a virtual machine running Proxmox Backup Server (PBS). Spoiler alert: it’s a bit more work than if you just slapped a drive into a physical box, but we’ve got this..

🔧 Overview

When you’re running PBS inside a Proxmox VE virtual machine and want to add USB drives as data stores, you need to:

1. Attach the drives to the VM.
2. Format and mount them manually in the shell.
3. Add them as data stores via the PBS GUI.
4. Make the mounts permanent using /etc/fstab.

---

🛠 Step-by-Step Instructions (with Example Commands)

1. Create Your PBS Virtual Machine

Create a virtual machine and install Proxmox Backup Server. This is your backup brain in a box.

2. Attach the USB Drives

• On your Proxmox VE host, go to your PBS VM settings.
• Click Hardware > Add > USB Device.
• Select the USB hard drive from the list and click Add.

3. Boot the PBS VM and Open the Shell

From the Proxmox GUI:

• Click on your PBS VM.
• Go to Console or Shell.

4. Identify the Drives

lsblk

Look for drives like /dev/sdb, /dev/sdc, etc. These are likely your USB drives.

5. Partition the Drives

Use fdisk or parted to partition each drive as GPT.

sudo fdisk /dev/sdb

• Press g to create a new GPT table.
• Press n to create a new partition.
• Write with w to save.

6. Format the Drives

sudo mkfs.ext4 /dev/sdb1

Repeat for each drive.

7. Create Mount Points

sudo mkdir -p /mnt/usb1
sudo mkdir -p /mnt/usb2

Each drive needs its own folder.

8. Mount the Drives

sudo mount /dev/sdb1 /mnt/usb1

Repeat for each drive.

9. Confirm They’re Mounted

lsblk

You should see your devices mounted to the paths you created.

---

📦 Add the Data Stores via PBS GUI

Now let’s make PBS actually use these drives:

1. Go to the PBS web interface.
2. Click on Datastore > Add.
3. Enter:
   • Name (e.g., USB-Backup1)
   • Path (e.g., /mnt/usb1)
4. Click Add.

Congrats! PBS now sees the drive.

---

💾 Make Mounts Persistent with /etc/fstab

Because Linux is forgetful after reboots.

1. Get the UUID of Each Drive

sudo blkid

Copy the UUIDs and note which one is which.

2. Edit /etc/fstab

sudo nano /etc/fstab

Add lines like this:

UUID=xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx /mnt/usb1 ext4 defaults 0 2

Do this for each drive.

3. Test the Config

sudo mount -a

If no errors appear, you’re golden. Reboot and verify with lsblk or df -h.

---

🧙‍♂️ Bonus Tips

• Take a VM snapshot before making these changes. Always good to have a time machine.
• Update your PBS system first with:

sudo apt update && sudo apt upgrade -y

• If things break after reboot: check your /etc/fstab syntax or UUIDs.

---

🏁 Summary

Adding USB drives to a PBS VM takes some manual magic, but once it’s set up, you’ve got flexible, external backup storage running in style.

So go ahead, mount up, back up, and sleep easy knowing your data has a solid home—even if it’s via a USB cable.