I may have missed it in this e-mail, but have you considered doing OS 
mirroring on your data disk pools?  I know that you are supposed to use 
TSM mirroring for Database and Recovery Log volumes, but I talked with 
Tivoli tech support on this issue several months ago and they couldn't 
give me a good reason to not use OS mirroring on your data disk pools.  
If you can afford it and you have two SSA drawers, why not just mirror 
one drawer to the other?  That way if you lose a disk, it should be 
transparent to TSM.  Just my 2 cents worth.

--
Jeff Rankin
Associate Technical Analyst, Excel Corporation
Email:   Jeff_Rankin AT cargill DOT com 

> -----Original Message-----
> From: jepson AT APPLE DOT COM [mailto:jepson AT APPLE DOT COM]
> Sent: May 24, 2001 5:23 PM
> To: ADSM-L AT VM.MARIST DOT EDU
> Subject: AIX Disk-pools; mirror, RAID or simple copy-pool???
> 
> 
> TSM Admin Group,
> 
> Sorry to bother the group with this yet again.  I know it was been 
> discussed before, and I wadded through many messages on ADSM.org 
> archives.
> 
> I have TSM 4.1.3 running on an H80.  My 100GB initial disk 
> storage pool, 
> which migrates to a AIT-2 tape storage pool has me concerned. 
>  I purge 
> this pool to tape each mid-morning after backups finish, and 
> again each 
> night before my evening backups start.
> 
> Now I?m a firm believer in a DB Copy-pool (TSM mirror) 
> however, no one 
> talks about a disk storage pool copy-pool.  If you have a 
> large initial 
> disk storage pool (ours is 100GB and could grow significantly 
> if we get 
> another SSA Drawer) there is a real threat of a disaster if 
> you loose a 
> disk in that disk array.
> 
> I was planning to run with a 100GB disk storage pool, and 
> then have that 
> mirrored (via TSM) to a disk storage pool copy-pool.  I did this on a 
> older version 2 server years ago.
> 
> So my question is if you have a significant amount of disk.  In this 
> case 200GB (six 36GB disks separated into two 3 disk volume groups).  
> What is the hot setup?!?
> 
> Here are the configuration scenarios I am considering:
> 
> 1) Setup two 3 disk volume groups, with one vg as the initial disk 
> storage pool, and the other a copy pool (TSM mirror) -- which 
> is what I 
> intended to do, yet doesn't seem to be an option in TSM 4 any more.
> 
> 2) RAID 5 the six 36GB disks into one volume group, and 
> utilize AIX RAID 
> to keep the disk pool healthy.
> 
> 3) Glome the disks into one 200GB disk storage pool, and continue my 
> daily purge  procedures.
> 
> 4) Setup disk vgs as in step one, creating the initial disk storage 
> pool, and the another disk storage pool with the pool type of 
> copy, and 
> backup the initial disk storage pool at specific times -- 
> this is what 
> TSM support recommended.
> 
> Any opinions and/or ideas would be appreciated.
> 
> Many Thanks,
> 
>          _/_/_/    _/_/_/  Jim Jepson, L&RE System Admin & Networking
>           _/        _/     Apple Computer, Inc.
>          _/        _/      3 Infinite Loop Cupertino, CA 95014
>   _/    _/  _/    _/       Direct: 408-974-6368  FAX: 408-996-3783
> _/_/_/_/  _/_/_/_/        MS:303-1SC,  E-MAIL:
>