Re: [TCLUG:11551] Hardware Question

["Carl Wilhelm Soderstrom" <carls@agritech.com>]

>Also, consider adding a tape drive to the machine.  DLT or DSS tapes work
>nicely and they're not too expensive.
        go for Seagate's (Sony's) AIT tape instead of DLT. it's about the
same cost for the drive (~$2200 internal, $2400 external); but about 3 times
as fast to load and seek, and much more reliable and efficient.
        DLT uses fixed read/write heads; so the tape has to go by at several
dozen inches per minute. if your data stream can't keep it fed fast enough
(likely to happen if you're doing backups over a network, and possible even
with local backups); the first thing it does is turn off data compression
(so it can keep the tape going at a constant speed). so there goes your
storage capacity. :( if that still isn't enough; it'll have to stop the
tape, back up, and race it forward again. this beats up the tape, the drive,
and destroys your time efficiency.
        AIT on the other hand uses spinning, helical-write heads (like a VCR
or DAT). so the tape only goes by at a couple of inches per second. if your
data stream can't feed it fast enough; it's not that expensive to stop the
tape and back up. AIT also can incorporate a flash memory chip in the tape
itself; which holds indexing and history information. this is what makes it
so very fast for seeks.
        they also claim that AIT uses a more durable medium. 
        there was a consultant who came to talk at the Twin Cities System
Administrators meeting a couple months ago; talking about various backup
technologies. he cam down pretty hard on the problems with DLT and said that
everyone he knows has been very happy with AIT. his site is
www.backupcentral.com; you might find some useful info there.

        on the downside, the tapes *are* expensive. I think it's ~$100 each
for the tapes with the memory chip; and ~$60 for those without. still, for a
few tapes in a professional environment, I think it can be a worthwhile
investment.
        
that said, I use a DDS-3 drive here at work; mainly because I don't need to
back up 25+GB of data. :) I only have a few GB to deal with; and they
usually go on several different backup tapes anyway. this HP SureStore
rocks. :) one of the advantages of DDS-3 to me; is that I can use the old
DDS-2 tapes which we have in abundance. 

Carl Soderstrom
System Administrator	307 Brighton Ave. 
Minnesota DHIA		Buffalo, MN	
carls@agritech.com	(612) 682-1091