Hello Mark,

> One-drive libraries are pretty much worthless
False

With our add-on SOS-MB (sorry only french) we use this technology.
and it works fine (SOS-MB is promoted in France by IBM/Tivoli)
We guarantee a "day - 1" recovery of the backup server (the worst case) and 
without the DRM of TSM
If we have one drive, we suppose that volumes of datas to backup are not very 
big 
The primary storage pool on disk must be big enough
Tape drive is only for offsite tapes
And the trick is to use a backup strategy with no need for reclaiming offsite 
tapes.
In this way, there is no reclaim at all (and no collocation) which is very 
practical in little companies with no specialist.

Joking with your style : 
Do yourself a BIG favor. Think about this strategy.
(For myself, I know, I have to think about improving my english)

By example : 
1 - You have 400 Go of datas, a disk of 400 Go and a LTO 3581
2 - First day of use : you do a full copy on tapes and each day after you copy 
all the new things of  the storage pool disk on tapes
3 - At the end of the week (by example) you put the tapes offsite with the 
database on an other tape
4 - You clear the disk storage pool and delete the same in the database
5 - You take a new set of tapes for the next week and do the same than the 
previous week
6 - You can rotate on 3 sets, by example

I hope it will help

Regards

Christian Bagard
SOS-restore - Aix-en-Provence - France
c.bagard AT sos-restore DOT com
www.sos-restore.com (in french)

----- Original Message ----- 
From: "Mark Stapleton" <stapleto AT BERBEE DOT COM>
To: <ADSM-L AT VM.MARIST DOT EDU>
Sent: Tuesday, October 01, 2002 1:19 PM
Subject: Re: Off site copy with one drive???


> From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU]On Behalf Of
> Etienne Brodeur
> > Is it possible if I have a one drive library to use a copy storage pool
> > for my backups?
> 
> Yes.
> 
> > I can backup to disk, then backup the diskpool to the copypool.  (this way
> > I should have all my data onsite and offsite).
> 
> Exactly. You backup from diskpool to offsite pool, and then you migrate from
> diskpool to primary tape pool.
> 
> > How do I then reclaim my copypool volumes?
> 
> You can't. TSM doesn't support a disk-based reclamation pool for reclamation
> of offsite tape pools.
> 
> > I can't reclaim to disk like I
> > do with my onsite volumes for some reason (I don't see why not since the
> > DB can track which file is on which onsite tape mount it and copy it to my
> > reclaimpool on disk.  Once that is done it can mount a scratch or copypool
> > volume and the offsite volumes would be reclaimed no?
> 
> One-drive libraries are pretty much worthless. Particularly if you have
> large-capacity tape volumes, your disk-based reclamation pool needs to be at
> least 40% of the maximum size of the tape volume. In the case of LTO tapes,
> that means 80GB of disk space for the reclamation pool.
> 
> Do yourself a BIG favor. Get a three-drive library.
> 
> --
> Mark Stapleton (stapleton AT berbee DOT com)
> Certified TSM consultant
> Certified AIX system engineer
> MCSE