1) No, they are only backed up once. (Assuming of course, that your BACKUP
STGPOOL command specified the same destination copy pool both times.).
BACKUP STGPOOL is an incremental backup; TSM checks the DB to decide whether
any file in the primary pool does or does not already exist in the copy
pool, and only makes a copy if there isn't already one in the copy pool

2) We back up the disk pool first, just because my primary pool is
collocated, so if I can backup the files while they are still on disk it
saves oodles of tape mounts to create the copy pool, which is not
collocated.  Whether you do disk or tape first doesn't really matter, if you
know for sure no migration will occur in between.

Whether or not you disable sessions depends on how precise you want to be
with your offsite copies.  If you want to guarantee, that EVERYTHING is
represented in your copy pool then yes, disable sessions, backup from disk
to tape, then tape to tape, then back up the DB.  In my case, with 500
machines backing up per day, I don't bother disabling sessions, 'cause I
don't have a large enough free window, and anything I miss on day one, will
surely make it to the offsite pool on day 2.

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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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