Yeh...i agree Joe. We have the same situation here. We have a 3583 with
LTO2 in a test/DR environment and it is painful to work with it, load
failures, locks up, you name it, just very inconsistent behavior. No
drive failures though and we have LTO2 in it. We also have a 3584 in our
production environment with 5 frames and 60 LTO2 drives and very little
problems. Like you eluded to, I just don't believe 3583 was ever meant
to be a real "enterprise" backup workload type library. We are very
please with our 3584 and LTO2 though.


-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of
Joe Pendergast
Sent: Wednesday, August 09, 2006 9:08 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: [ADSM-L] FW: Tape Drive Choices: What, and why?

As soon as you said 3583, I felt the pain in my backside twinge.  It is
of
no wonder that they discontinued the 3583 "!@#$%^&* garbage" (as you put
it).  The drives we have used in it are very stable, but the loader, and
library are constantly having problems.  Of course, IBM continuously
blames the drive for the problems, but after swapping drive after drive,
the loader replacement is the thing that usually fixes the problem.

We have a 3583 library that I would not suggest for anyone except in
very
light duty (currently has LTO1 drives). It goes out once every month (or
less).

Then we have a 3584 library with full redundancy and the service bays
running as 4 logical libraries on two backup softwares.  It is very rare
that we have any problems.  Occaisionally, we get a stuck LTO1 tape, but
with care have not lost any.  Our LTO1 and LTO2 drives are workhorses.
They are busy for up to 22 hours a day.  I am very pleased with the 3584
technologies.




Zoltan Forray/AC/VCU <zforray AT VCU DOT EDU>
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Re: FW: Tape Drive Choices: What, and why?






You won't get that sentiment from me.

As I have said in the past, my experience with LTO2 and 3583 library is
that they are !@#$%^&* garbage.  Even IBM stated that LTO was never
designed to handle the load we are putting through them (we have over
400
tapes in use per 3583-L72 library).   Every drive we purchased has been
replaced AT LEAST twice, in the past 1.5-years we have had LTO
drives/libraries.  The libraries need to be "power cycled" at least once
a
week, sometimes more (absolutely every piece of firmware/software
between
the AIX systems and the libraries themselves, have been updated to the
latest available - no it's not power - everything is on
UPS/battery/conditioned).

This is why we are moving to 3592-E05 drives.  Besides the capacity
difference, the reliability we have seen with 3590 drives (even those
that
are 10+ years old), far exceeds the LTO's.  We mount 1000's of 3590
tapes,
daily.  If we have 1-failure in 2-3 weeks, that is rare.

Granted the 3592-E05 drives are new and "disposable/FRU" technology vs.
field-repairable, so time will tell.




"Allen S. Rout" <asr AT UFL DOT EDU>
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Re: [ADSM-L] FW: Tape Drive Choices: What, and why?






>> On Tue, 8 Aug 2006 11:37:37 -0400, Paul Zarnowski <psz1 AT CORNELL DOT EDU>
said:

> This was more true with LTO-1 than with -2 or -3.  The later
> generation drives can vary their speed to try to match the data rate,
> thus avoiding some backhitching.  But Tom is correct that the motors
> in the 3592 drives are probably bigger and more powerful, and can
> thus backhitch more quickly.  (this is my guess, not fact)


If I recall correctly, the superior 3592 backhitch was related to a
special track ("servo track"?) which permitted precise high-speed
positioning.  This also aids general purpose seek behavior. The
varying speeds would certainly help.

The basic summary of the responses I've gotten offline is that LTO is
doing much better than it had initially; it seems that the current
3592s still have an edge, but not nearly so broad as was the case.

Most interestingly, I didn't see any particular discussion about any
tech _other_ than LTO or 3592, apart from one "Pulled back a bloody
stump" story about helical-scan.

This meshes neatly with a campus-level query I sent out a few weeks
back; to my surprise, LTO utterly dominated that list of tape techs,
too. Discussion of other tech lines was all in the past tense.  It
appears that the LTO alliance has kicked tush and taken names.  Rawk
On.


- Allen S. Rout