The holding disk contains the tape images, when a full backup have been made.
Can these be deleted, or are they needed when creating incremental backups?
Another way to ask the same. When a full backup have been made. How does Amanda know which files have changed, and should therefore be backup in next incremental backup job?
I would imagine that Amanda would compare each file to be backed up against the ones in the tape images on the holding disk.
Or does Amanda make a checksum of each file it backs up, and if the checksum have changed on a file, then it is included for incremental backup?