For a while I backed up my most important data to Backblaze. I also wanted a last-resort cold copy of both my servers and my file share, one that's simple to set up and simple to restore after a total loss. Every three months I run this by hand, alternating between two sets of disks. You need a USB hard drive large enough to hold all the VM backups.
Proxmox VMs
- Plug the drive into the first node.
- In the web UI, open that node > Disks, then wipe and initialize the drive. You can also do this in the Shell with cfdisk and mkfs.ext4.
- Open the Shell on each node and create the mount point. Then mount the drive on the node it's attached to. Check the device name first. Mine was sdf1:mkdir /mnt/Cold-Backups
mount -t ext4 /dev/sdf1 /mnt/Cold-BackupsThe first node can use Disks > Directory > Create: Directory instead. The other nodes still need the mount point created by hand. - Add the storage to the cluster:pvesm add dir Cold-Backups --path /mnt/Cold-Backups --content backup
- Go to each VM on the node with the drive, open Backup, and back up to Cold-Backups.
Before you start backing up, confirm the disk is really mounted. If it isn't mounted at /mnt/Cold-Backups, or you're on the wrong node, the backups will land on the host's system drive. Check the Cold-Backups storage under that node and make sure the size matches your drive.
When a node's VMs are done, unmount the drive (umount /dev/sdf1) and repeat on the next node. You can remove the storage from the cluster afterward. I leave it configured, so next time I just plug the drive in.
Proxmox Backup Server
PBS works almost the same way. In the Shell, I wiped the disk and created a partition with cfdisk, then ran mkfs.ext4, created the mount point, and mounted it. Then I added it as a datastore. After finishing, I remove the datastore so the OS doesn't hang at boot looking for a disk that isn't there.