From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU]On Behalf Of
Talafous, John G.
> We are finding that, due to incremental forever backups, recovery
> times are
> extremely long because of tape mount after tape mount after tape
> mount. In a
> real disaster, we expect to take an entire day or more to recover a single
> server. With a limited number of tape drives the recovery time
> required for
> 100 servers could take weeks.
>
> Has anyone else run into this dilemma? What is TSM's direction? How can I
> speed up the recovery process?

Several things should be done when planning TSM and disaster recovery:

1. Use a disk-based directory management class. It makes dir scans *much*
   faster.
2. Collocate data from your most cirically important machines; or,
3. If you're using TSM 5.1.x, consider use of the MOVE NODEDATA command.
4. Plan your disaster recovery scenarios, and practice them (*before* you
   have to).
5. Buy enough library (and enough tape drives) to handle mass restores. The
   slower the mount time on your drive, the more drives you'll need.
6. If your IS department lacks sufficient TSM experience to integrate it
into
   your DR plans, hire a consultant to help you get it right.

And if your SLAs can't stand significant downtime (> 2-4 hours), then no
backup/restore software will do the job. As our Sister Wanda P. has preached
before, you need to be looking at clustering/real-time
mirroring/HACMP/whathave you.

--
Mark Stapleton (stapleton AT berbee DOT com)
Mark Stapleton (stapleton AT berbee DOT com)
Certified TSM consultant
Certified AIX system engineer
MSCE