Backup hangs at 14%

[rustybird]

If you’re still using a legacy ‘file’ driver pool, all of the VMs stored in it that are selected for inclusion in the backup must remain shut down until the backup completes. Other than that,

Backup stuck at 99%

The underlying error for backups that are silently hanging can often (maybe even always?) be revealed by setting the backup destination to dom0 instead of a VM: Make sure that your destination path in dom0 has enough free space for the set of problematic VMs.