SUMMARY: 4-8 gig dats or sales hype?

From: Tanya Herlick (
Date: Fri Aug 19 1994 - 08:41:54 CDT

I had originally posted soliciting opinions about dat drives that
claim to fit 4-8 gigs of data on a 90 meter tape. I can't get it to
work (I have an HP 38540A drive).

The general consensus about these drives seems to be that 3-3.7 gigs
of data on a 90 m tape is average, but of course it depends on the
data you are backing up. ASCII compress way more than binary or
compressed data.

So I decided to dump my news partition (almost 1 gig) several times
(7 to be exact) figuring that since all the files on this partition are
simple ASCII, i should be able to dump this 7 or 8 times onto a 90 m tape.

I got a little more than 4 gigs onto the tape. Just thought this was
interesting and more than a little annoying. It doesn't get me any closer
to solving the problem but it tells me that either HP is lying about
the capacity of their drive or that we're missing *something* *somewhere*.

Summary of other comments I got:

1) Go with exabyte (8 mm) instead. Easier to set up and you can get
up to 25 GIGs of data onto a tape (wow, even if you get only half of that
it's still great)

2) Go with DDS-2 DAT drive. This will allow you to use a 120 meter
tape instead of a 90. Much more likely to get up to 8 GIGs on a 120
meter tape.

Tanya Herlick 
System Administrator at O'Reilly and Associates	
90 Sherman St. Cambridge, MA 02140   ph: 617/354-5800 fax: 617/661-1116
to reach me: 617/499-7459     email:; uunet!!tanya

This archive was generated by hypermail 2.1.2 : Fri Sep 28 2001 - 23:09:08 CDT