Backup

The backup of a single guest VM consists of the following steps:

Save guest VM configuration (for LXC guest VMs).
Create a new backup snapshot (default), suspending or stopping the guest VM as requested.
Execute vzdump and save data.

Backups can be performed for guest VMs in any power state (running or stopped). The Proxmox hypervisor will automatically create the required backup snapshot and remove it after the backup. Any other guest VMs snapshots will be unaffected.

The Proxmox Plugin will inform you about every guest VM backup start and finish:

 JobId 68: Start Backup JobId 68, Job=proxmox.2018-01-25_11.25.05_21
 JobId 68: Using Device "FileChgr1-Dev2" to write.
 JobId 68: Volume "Vol-0002" previously written, moving to end of data.
 JobId 68: proxmox: Start Backup vm: ubuntu-container (101)
 JobId 68: proxmox: Backup of vm: ubuntu-container (101) OK.
...

The backup will create a single (.vma) file for any QEMU guest VM and two files (.conf and .tar) for any LXC guest VM which is saved. Inside Bacula, those are represented as follows.

/@proxmox/qm/<name-label>/VM<vmid>.vma for QEMU guest VMs
/@proxmox/lxc/<name-label>/VM<vmid>.conf and
/@proxmox/lxc/<name-label>/VM<vmid>.tar for LXC guest VMs

Multiple files will be created during a backup if multiple guest VMs are backed up with one job. However, note that backing up multiple VMs goes against hypervisor best practices. The distinct file names as shown above allow to locate the proper guest VM archive for restore.

Tip

You can exclude machine disks from Proxmox image backup in the Proxmox Console VM Disk Settings screen.