Hi dear TSM fans,

following problems with backups writing to tape and using more than 1
session (DB2), we had to set COLLOCATION OFF to our archtape storage pool (a
sequential tape pool). We have now a recurring problem by restoring more
than one DB2 backup at the same time. Some of them get media waits, which is
normal as the node restoring can have their data on the same volume.

I would like to propose a slight change in the collocation concept for
backup/archives written directly to sequential storage pools (tapes):

- stay with the actual principe of a minimum of node per tape - one if
enough tape volume checked-in, more than one of course if not enough tapes.

BUT 

- with backups having more than 1 session, mount as many tape volumes, up to
the number of sessions or to the max number of mount points. At the next
backup for the same node, same tape volume will be used, if not yet FULL of
course.

Having this, we'd have optimum backups AND restores, full speed to tapes, no
media contention !

Please send your opinion,

best regards,

                René LAMBELET
                NESTLE  SA
                GLOBE - Global Business Excellence
                Central Support Center
                Information Technology
                Av. Nestlé 55  CH-1800 Vevey (Switzerland) 
                tél +41 (0)21 924 35 43   fax +41 (0)21 703 30 17
                mailto:rene.lambelet AT nestle DOT com