Use Borg, and copy the whole image. Borg will compress and deduplicate it, so you only backup the changes each time. You'll get point in time historical backups

Use Borg, and copy the whole image. Borg will compress and deduplicate it, so you only backup the changes each time. You'll get point in time historical backups, so if you accidentally delete stuff, you can find it again. Useful because data loss isn't always just hardware failure!