I'm not sure if this will answer all your questions, but marking a tape as
"destroyed" changes only one thing:  it tells TSM the tape can't be mounted
any more.  It does NOT remove any of the backed up files on the tape from
the DB.

PROOF:
When you are working onsite, if you mark a tape as DESTROYED, you can go
back and change it to READWRITE again, and keep using as though nothing
happened.  THAT MEANS ALL THE DATA IS STILL IN THE DB.

So,

1) If someone tries to restore a file on a "Destroyed" tape, TSM will try to
mount the copy pool tape instead (unless it is marked OFFSITE)
2) The primary tape volumes will still show up in your storage pool
3) The backed up data will still show up in all the occupancy counts.
4) The tapes should still show up as PRIVATE in the libary.

The DB entries for the primary copy of the backed up files do NOT go away
until you either: 1) do DELETE VOLUME w/ DISCARD DATA, which you should NOT
do because it destroys the pointers to the files in the COPY POOL, or 2)  do
a RESTORE STGPOOL.  That just means the primary files MOVE from the tapes
back to somewhere else  (which may account for one of your tapes going back
to SCRATCH.).


Hope that helps some...
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Wanda Prather
The Johns Hopkins Applied Physics Lab
443-778-8769
wanda_prather AT jhuapl DOT edu

"Intelligence has much less practical application than you'd think" -
Scott Adams/Dilbert
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