Jeff,
from financial point this Exadrive might seem very attractive. But are you
sure it would fit in TSM environment without performance degradation. For
me this might be something very similar to cheap "RAID" advertized by PC
mainboards but with all the problems IDE/EIDE/ATAPI devices have - no
release of the controller/device until operation finishes, lack of tagged
(or any) command queueing.
Thus you will get very inexpensive storage but at price of performance
problems. I guess it would be slower than LTO you already have and the
cheaper (and faster) deal would be to buy more cartridges.
And btw. what is the price of an IBM 200GB disk ?? AFAIK they even do not
offer 180 GB as Seagate does and larger SCSI one is 73 GB.

Zlatko Krastev
IT Consultant




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Subject:        hardware questions before I buy

We have a small TSM system.  I'm looking to expand it.  Of course, I'm on
a budget.

Currently we are on an RS/6000 H70 with an IBM 3581 tape changer.  We have
almost no disk space available for disk storage pools.  The machine is
dedicated to running TSM.

I am considering adding the following

IBM 3583 with two LTO drives, starting out with an 18 tape capacity.  I'm
not too worried about this part of it, correct me if I'm wrong, but I
think this is a known performer.

Exadrive Diamond SCSI -> ATA Storage Array.  This piece of hardware comes
with a 30 day money back guarantee, and a three year warranty.  I can get
2 TB of disk for the price of about 200GB of IBM SCSI disk.  The company
web site is http://www.exadrive.com  Does anybody know anything about this 
company, or this specific Storage
Array.    It plan to use it for disk storage pools for our nightly backups
(around 250GB) , which I will move to tape during the day.

-JeffR
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