Joined: 30 Nov 2013 Posts: 590 Location: The Universe
Been there, done that.
Do not try to “stack” multiple multiple disk volumes on one tape volume. First, as Mr. Sorichetti states, unless you have extremely high capacity tape media and tape drives, just one disk volume will almost certainly extend to more than one tape volume, which pretty much negates the advantage of “stacking” the volumes on one tape volume or volume set. Second, as Mr. Sorichetti states, you lose the advantage of dumping volumes in parallel using separate jobs or multiple tasks in ADRDSSU.
I disagree with expat about dumping the disk to virtual tape. With virtual tape you're doing what amounts to an inefficient disk to disk copy; the virtual tape supervisor will then create physical tapes from the data on its disk.
Personally, I think – but cannot prove – that tape “wastage” for full volume disk dumps is a non-issue. You get tape “wastage” when you have a small data set on a single tape volume. Virtual tape attempts to fight this by “stacking” these itty bitty data sets onto a single real tape volume. Disk dumps, on the other hand tend to be multi-gigabyte data sets. You may well have hundreds, perhaps thousands of itty bitty disk data sets in one disk volume image on the tape volume, but there's no real tape "wastage."
Am currently doing Backup with DUMP FULL _ALL EXCP.
Works fine - Supervisor was not happy with my coding skill.
Otherwise with little bit of corrections on parameters and positional adjustments I was able to take VOLS back up to Tape.