Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!rex!ukma!abbott
From: abbott@ms.uky.edu (Joel Abbott)
Newsgroups: comp.unix.questions
Subject: Re: Exabyte stackers / disk backups
Message-ID: <1991May21.141242.21247@ms.uky.edu>
Date: 21 May 91 14:12:42 GMT
References: <1991May21.070102.2673@newshost.anu.edu.au>
Organization: The Jimi Hendrix Fan Club
Lines: 40

mbl900@anusf (Mathew BM LIM) writes:
>Hi,
>	We are thinking of getting an exabyte stacker for a Sun 4/330 to
>act as a backup server. 
...
>- How reliable are they?

the exabytes themselves are pretty good.  i've been using a few of them
for about a year now.  read/write errors are seldom, and the eccs seem
to do the job.

>- What is their transfer rate (eg how long would it take to back up a
>  1GByte filesystem)? 

depends on what you are backing up, whether it is over the network, and
the throughput of the network (is it noisy, etc).  our network is
pretty uncluttered at night when backups take place.  i get about 10
(or a little more) megs/min over the network from a decent machine like
a sparc.  we also have some vaxen that won't die (i'd shoot them, but
they have quite a few gigs of disk space that we can't throw away!  :)
and they transfer over the network at a snail pace of around 2
megs/minute on a good day.  the sparcs do just about 15 megs/min
locally.

>- Any experience with the newer 5GByte exabytes as opposed to the 2GByte
>  systems?

nope, but i sure wish i did!  there is also a 25gig machine from
exabyte as well.  they claim up to 90meg/min transfer rate, but you
will only get as high as your slowest component - your network and/or
your disk.

our exabytes are running on sparcs (sunos 4.1 and 4.1.1) and a
decstation 2100 (mips based thingy running ultrix 4.0, we had problems
getting pre ultrix 4.0, bad driver or something).  each of the sparcs
and the 2100 also have between 2-4 scsi drives daisy chained.  we also
have an 8mm running on a next machine.  we haven't had much luck
getting an exabyte running on an at&t 6386 running sysvr4.0.
-- 
Joel Abbott, DoD#272 -> abbott@ms.uky.edu, abbott@ukma.bitnet, uunet!ukma!abbott