On Fri, Nov 19, 2004 at 04:02:11PM -0600, Hart, Charles wrote:

> In working with our Oracle DBA's they feel TSM< should manage the RMAN Oracle 
> Retentions etc...   Is there a "Preferred method?"  If so why?

The preferred method is letting RMAN manage the retention policies of the
backups. Especially so since Oracle 9i: RMAN works absolutely great for
this. It was explicitly designed to be able to implement database
retention policies. It keeps track of stored backups, and if you'd let
TSM expire backups you'd lose some RMAN functionality like e.g. "CHANGE
BACKUPSET foobar KEEP FOREVER".

> "Note on page 85 of the RMAN Backup and Recovery Handbook it says:
>
> "If you are using a tape management system, it may have its own retention 
> policy.

Note the "may".

> If the tape management system's retention policy is in conflict with the 
> backup

Note the "if". This "if" is quite important. The TDP for
Oracle-documentation quite clearly explains how to configure the TSM
retention policy so that it does not conflict with RMAN.

> That is why I was leaving it up to the Tivoli retention policy to be used
> instead of RMAN retention policies.

If he keeps insisting on doing so, he'll be creating a dangerous
situation for himself. For example, the "CHANGE ... KEEP FOREVER" will
*not* work as expected: your backup *will* be gone when TSM expires it.
In addition, he'll have to perform regular CROSSCHECK commands on the
recovery catalog, and delete objects with the UNAVAILABLE status. RMAN
still thinks it has the backups, while TSM expired them.

So: configure TSM to not ever expire any backups made with RMAN. This is
quite easy, and is explained in the installation documentation of the TDP
for Oracle. Let RMAN take care of the database retention policy. That's
what it's designed to do.
--
Jurjen Oskam