Mastering Proxmox - Third Edition

Issue – how can Proxmox back up only the primary OS virtual disk instead of all the virtual disks for a VM?

By default, a Proxmox backup will back up all the virtual disks assigned to a VM. If we want to exclude certain virtual disks from the backup process, we only need to add the backup=no option at the end of a virtual disk line item in <vm_id>.conf, as follows:

virtio0: rbd-hdd-01:vm-101-disk1,size=80G virtio0: rbd-hdd-01:vm-101-disk2,size=200G,backup=no 

In the previous example, the virtual machine has two virtual disks. The disk1 is for the primary OS and disk2 is for the secondary. By adding backup=no, Proxmox will skip this disk during the backup process and only back up the primary disk.