I agree that many sites do not give enough consideration to the
possibility of the media going bad, nor do they check and manage the age
and usage of the media they have.  (We do.)

But, the way to deal with this problem is NOT to drag ALL your data
across the network again!

*       Creating a copy pool tape with ADSM insures that your data is
readable after it is created.

*       Primary pool tapes get reclaimed regularly, which insures
regular media turnover.
*       Copy pool (usually offsite) tapes are relaimed as well, and
return to the scratch pool.

*       If I have a problem reading a tape during reclaim, I can
recreate it with a RESTORE command from another copy pool.

*       If I am concerned about the age of a tape because of the number
of passes or shelf life, I can just enter a MOVE DATA command, and ADSM
will give the tape back.

Of all the methodologies that have been mentioned in this thread, the
ADSM setup makes it the EASIEST to manage the media, and still without
using full dumps.

ADSM lets your network "work smarter, not harder"!


===============================================================
Wanda Prather
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
===============================================================








> ----------
> From:         Douglas E. Babcock[SMTP:babcock AT tmd DOT com]
> Sent:         Friday, March 06, 1998 12:52 PM
> To:   ADSM-L AT vm.marist DOT edu
> Subject:      Re: The "incremental forever" paradigm
>
> At 11:05 AM 03/06/98 -0600, John Schneider wrote:
> *SNIP*
> >Please explain to this novice why, on the one hand, we
> >implement a backup strategy to cover the possibility of loosing
> disks,
> >be we ignore the possibility of the backup media itself going bad?
> >
> *SNIP*
>
> Also, let's not forget that remote host disks do go bad, and that
> performing a full restore from an "incremental forever" backup set
> will usually result in a extraordinary number of tape mounts and
> a correspondingly long restore window. Periodic full backups help
> alleviate this problem.
>
> Regards,
> Doug
>
> --
>
> Doug Babcock <mailto:babcock AT tmd DOT com>
> StorageTek TMD, a division of Storage Technology Corp.
> Standard disclaimers apply (free copy on request)
>
> To see what I/we do, visit the StorageTek CAM/EBF home page at
> http://www.stortek.com/StorageTek/software/cam/camhome.html
>
> --
>