You can avoid transferring some disk data with the [NOBAK] title in the VM disk. However, a VM snapshot isn't capable of ignoring a disk. This would require a change either in the way we do backup in XO (not using VM.snapshot, but VDI.snapshot instead) or modify XCP-ng API to support VM.snapshot with excluded disk.
The first option will make quiesce snapshots impossible. The other one is a bit more complicated to realize, but not impossible.
The issue already exists in our bug tracker: https://github.com/vatesfr/xen-orchestra/issues/2560
julien-f created this issue in vatesfr/xen-orchestra
closed
[Full backups] Supports `[NOBAK]`
#2560