The 4mm problems I've experienced over the last 6-7 years have occurred
multiple times in multiple data centers, with multiple drives.  I've
heard this same thing from several other people, as well.  Maybe they've
improved things over time, with DDS3.  Just last week, a drive broke,
the tape got stuck, and nothing would backup -- 4mm, not the working 8mm
drive sitting next to it.

It's actually pretty easy to find 8mm.  Of course, they cost more.
http://www.dirtcheapdrives.com/ has one for $2119, which is a bit pricey
for many.

DLT is a better solution, perhaps the best "Lintel" based solution.
Prices range from about $1600 to whatever you want to spend, depending
on features.

The question is, "What's your data worth?"  If you need backups you can
rely on, well, you get what you pay for.

Since I co-manage a large data center (multiple terabytes on 25+/-
RS/6000 servers) here at Sprint, we pay for 3494 and use Adstar.  (I'd
rather use DLT, myself, but I'm not the one footing the bill.)  We also
use 4mm and 8mm, for system backups, and yes, 4mm has problems, at
times.  Adstar is a bit quirky, too, but that's usually a software
problem, not a hardware problem.

At my last job, we used 4mm, 8mm, DLT, and 3494 in a small to medium
data center (10's to 100's of Gigs.)  The only drives that (almost) ever
had problems were, once again, 4mm.  The two jobs before that had
problems with 4mm, as well.  Unfortunately, 4mm was the only backup
medium for those two sites.  We lost important data countless times.

I think my experience stems from environments that use tape drives
several hours a day, and rewriting of tapes about once a week.  That
wears on things a bit.  (Not so with the other methods, within reason.)
Of course, we cleaned the drives, rotated tapes, etc.

No, 4mm doesn't die all the time, but, since our data is literally worth
hundreds of millions to billions of dollars here at Sprint, and since we
have several terabytes online, we would never consider 4mm for our
backups.

Again, I'd use 4mm at home or for a SOHO, and maybe for a small data
center -- maybe.  Heck, I'd use 4mm over a Travan, any day.  It depends
on the value of my data.

Unless they've really improved the reliability with DDS3, I'd never use
it in a medium to large data center, except to make weekly system
backups, since the systems aren't changing all that often -- I can
always go back to last week's tape and be OK.

The really expensive stuff is FileNet -- a 14" laserdisk backup system.
I can't imagine a need for that setup where I am.

In the original post, what is being backed up?  Is 8mm and DLT (or
greater) a moot point?  If it's just a few gigabytes backed up a few
times a month for home/SOHO use, it really doesn't matter -- use a
Travan or a 4mm.  If you're in a data center, things get updated often,
and the backups are really important, don't go cheap.

-----Original Message-----
From: mosten [mailto:mosten@topekafoundry.com]
Sent: Thursday, March 30, 2000 3:34 PM
To: kclug
Cc: mosten
Subject: RE: kclug - What tape drive would you recommend?

On Thu, 30 Mar 2000, michael d hoskins wrote:

> How large are your backup needs?
>
> 4mm - small backups
DDS 3 (mine holds 12 native 24 compressed) and they get bigger the more
money you spend....

> 8mm - med.  backups

Getting hard to find anymore...I've got a 13 gig if anyone is
interested.

> DLT - large backups

Very expensive...used when you need to backup terrabytes of data..get
out
your wallet.

>
> (Or 3494 for VERY large systems -- ADSM/Adstar/TSM.)
>
> 4mm, unfortunately, has issues.  I've seen instances where the tape
> stretched, got stuck in the drive, the drive got misaligned or dirty,
> the drive broke, etc.  I'd really only recommend this for home and
SOHO
> use, and only if you can afford down time.  This is NOT a data
> center/enterprise solution at all.  4mm is cheap, and "cheap" is the
> operative word.  Again, at home, it's OK.  I guess any tape backup is
> better than none at all, but the only time you ever need to restore is
> when it's critical....  :-(
>

I'd have to disagree. *everyone* uses DDS3 drives, I've personally never
had any problems. Its just like everything else, take care of it, and it
will work perfectly.  As far as the tapes stretching, and losing
data...I
think that your experience is not the norm.