On 02/23/2012 04:11 AM, Daniel Sparrman wrote:

Yes, you can share it with multiple backup applications by defining
more than 1 library. Each library needs it's own dedicated drives
though (as with all VTL's).

Since TSM& BackupExec writes information differently to the VTL,
data backed up using TSM wont be deduped against data backed up with
BackupExec. If this has any impact on your dedup ratio depends on
the amount of information you store with each application. At a
certain point, TSM will have enough "own" information stored to
dedup against, and so will BackupExec.

I don't know how the TX7650 operates in detail; but I do know that for
some devices (my example is EMC's Data Domain, which we're using for
some stuff) there's quite decent dedupe across different applications
backing up "the same" data.

Figuring out what "the same" means can be complicated, though.  For
example: say you had a production Oracle app running on RHEL, with
developers and QA folks running against a local copy running on their
workstations.  You use RMAN on the production boxen, and use Backup
Exec on the workstations, both streams eventually finding their way to
the same Data Domain.

So long as you don't compress the streams, a large fraction of the
database information should dedupe.


Another interesting case of "the same" might be file-based backups and
image backups of the same machines; say you're dropping snapshots of
some devices for fast DR purposes, but much more limited file-based
backups for user experience.  Again, so long as you don't compress or
encrypt the streams, "some" of the data (maybe even "much"?) should
dedupe neatly.


- Allen S. Rout