From: medici@dorm.rutgers.edu (Mark Medici)
Newsgroups: comp.sys.novell
Subject: Re: Novell Tape Backup Software
Date: 10 Sep 92 22:08:54 GMT
Organization: Rutgers Univ., New Brunswick, N.J.

Jon.Biddell@unsw.edu.au (Jon Biddell) writes:

>In article <1992Sep5.032039.15644@monu6.cc.monash.edu.au> dazz@monu6.cc.monash.edu.au (Mr D.K. Woodman) writes:

>>I am soon to implement a DAT tape backup system for a Novell 3.11 lan of
>>approx. 50 users and am looking for software recommendations/opinions.

>DAT will be dead within two to 3 years as a backup medium - Why not look at 
>an industry-standatd EXABYTE tape drive....


Excuse me, but I seem to have overlooked the "ANSI.Biddle Standard For
Helical Scan Data Storage Devices".

{Sole source (a.k.a., "Proprietary")} != "Industry Standard"

DAT is a fine storage medium, offering excellent performance, high
capacities, quick positioning, and the lowest cost per megabyte of any
mass storage device I'm aware of.  90m DDS-certified DATs can be had
for under $10 each, and can hold up to 6GB of compressed data (though
4GB is more realistic).  Longer tapes are becoming available that will
boost the compressed capacity to 8GB per tape.  DAT drives from
different manufacturers are interchangeable, and tapes are generally
transportable from one brand tape drive to another (depending on
whether compression is used or not).

We have used Exabyte drives for years to back-up our Suns.  The drives
are expensive to buy and very expensive to have repaired.  DDS-certi-
fied 8mm tapes are costly, and tape positioning is slow.  Reliability
has also been a problem for us, even in a controlled machine-room
environment.

We are switching over to DAT drives now, and are very pleased this
far.  We have single-tape DAT drives from several manufacturers (HP
and Archive come to mind), and a DAT stacker from BoxHill Systems.
All of these have completely met our expectations.  Given the growth
I've seen in the DAT drive market, the rapidly dropping price of the
drives and tapes, and the availability of drives from several
manufacturers, I see no basis for your outlandish prediction of DAT's
immanent demise.

In fact, if I was to speculate on the survivability of any of the
currently popular data tape formats over the next 3 years, I would
tend towards predicting that the 8mm format, not DAT format, will
experience the greatest drop in market share (unless Sony decides to
put an end to Exabyte's exclusive rights).  Being proprietary, it
certainly is the least favorable format, IMHO.  However, I certainly
doubt that 8mm data drives will disappear from the market anytime
soon.

I do feel comfortable predicting that DAT data drives will continue to
drop in price and increase in market share.  As individual workstation
drive capacities increase to accommodate larger operating systems/GUIs
(Windows, Win/NT, OS/2) there will be a new need for high-capacity
drives on stand-alone machines.  DAT is much more suited for this than
8mm.  Not only is the price already more reasonable, (and I expect to
see DAT drives for under $800 within 3 years, and $600 wouldn't
surprise me), but the form-factor is better suited to installation in
stand-alone workstations.  Also, the low media cost ($10/DAT, $18/8mm,
and $20+/QIC) makes it even more attractive.  Finally, the relatively
quick random-access times (compared to other tape drives) give DAT
drives the potential to be used as near-line mass-storage devices, in
addition to their role as backup devices.

>>I know of Maynard software and drives as well as Arcserve Solo which is
>>the workstation-based version of Arcserve. Another I have heard of but
>>no details about is called "NovWare".

I avoid Maynard products (with the exception of the Archive line) at
all costs based on past experiences.  I've had no experience with
ArcServe Solo.  I tried Emerald's software and hardware, and found it
very problematic.  We use Mountain's software and drives for
workstation-based Novell backups, and are happy.


PLEASE READ:

Before we get into a holy war over "my tape format is better than
yours", let me add this semi-objective summary:

Both DAT and 8mm formats are good, useful methods of achieving high-
capacity data archiving.  When similar compression and interface
methods are used, each provides satisfactory data throughput and
reliability.  Because of its design, DAT drives can reposition to
different parts of the tape more quickly than 8mm drives, which could
make selective file restoration quicker.  The wider selection of DAT
drive manufacturers results in lower hardware prices and better avail-
ability, while the sole source limitation of 8mm drives results in
higher prices.  In all reality, neither is likely to disappear from
the market any time soon, and either (if properly implemented with a
good controller and software) will make excellent backup devices.

BTW, all opinions and expressed or implied recommendations are soley
my own, and do not necessarilly reflect the views of my employers.-- 
_________________________________________________________________________
RUCS     | Mark A. Medici, Systems Programmer III, User Services Division
User     | Rutgers University Computing Services, New Brunswick, NJ 08903
Services | [medici@gandalf.rutgers.edu]                    [908-932-2412]
Newsgroups: comp.sys.novell