TSM can give very quick restores, but beware fragmentation in uncollocated
tape pools. We had to rebuild a small (350GB) unix server last year that
required upward of 300 tape mounts, and finding a single file in the middle
of each tape. It took days.

Since then I have gotten funding to buy enough tapes for collocation, and
last week at 200GB restore took about 45 minutes.

- Kai.

> -----Original Message-----
> From: Joni Moyer [mailto:joni.moyer AT HIGHMARK DOT COM]
> Sent: Wednesday, 05 March 2003 7:21 AM
> To: ADSM-L AT VM.MARIST DOT EDU
> Subject: progressive backup vs. full + incremental
>
>
> ---------------------- Information from the mail header
> -----------------------
> Sender:       "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>
> Poster:       Joni Moyer <joni.moyer AT HIGHMARK DOT COM>
> Subject:      progressive backup vs. full + incremental
> --------------------------------------------------------------
> -----------------
>
> Hello everyone!
>
> I was wondering why the full + incremental would result in a
> longer restore
> time than the progressive backup methodology?  From several co-workers
> point of view they thought that it would be quicker on the full +
> incremental because you wouldn't have to go back to the
> beginning backups
> of the file and restore all of the incrementals, you would
> just go back to
> the most recent full backup and apply the incrementals after
> that point.
> When I went to explain the reasoning behind this, I had some problems
> understanding the concept myself, so I was hoping someone
> could explain
> both methods and why they differ in restore time and why
> progressive is
> better than the full + incremental.  Thank you so much for
> any help you can
> lend on this matter!
>
>
>
> Joni Moyer
> Systems Programmer
> joni.moyer AT highmark DOT com
> (717)975-8338
>