RE: OT: tape backup

[Paul Bunn <Paul UltraBac com>]

Of course I checked prices -- with TechData, a major distributor.  Congrats with
finding DLT media for $54 -- that's a great deal, and yes that's cheaper than
Ecrix media,  but note that the DLT7000 is around $1000 more to purchase.
Ampex now have quad-density that allows 660GB per cartridge.  You seem to take
great delight in pointing out the most minor of mistakes, so please allow me to
return the favor:

What school of math are you using ?
DLT IV cart = 40GB native capacity (only with DLT8000) = $54
$54 / 40GB  =  $1.35/GB
LTO = 100GB native = $131 (per pricewatch)
$131 / 100 = $1.31/GB

Seems to me that $1.31/GB < $1.35, maybe you just like to pay more per GB.  If you
use the more common DLT4000 or DLT7000, the $/GB figures for DLT are much worse.

Regards,

Paul Bunn, UltraBac.com, 425-644-6000
Microsoft MVP - WindowsNT/2000
http://www.ultrabac.com
 


-----Original Message-----
From: W Bauske [mailto:wsb@paralleldata.com]
Sent: Monday, March 26, 2001 3:56 PM
To: axp-list@redhat.com
Subject: Re: OT: tape backup


Paul Bunn wrote:
> 
> I think it fairly clear from my previous post that I was quoting pricing on a
> single tape cart -- not $/GB ratios.  If you want the best value $/GB, then
> probably LTO with its 100GB native capacity makes better sense, or hell, maybe a
> DST with 660GB native cartridges at only $445 each is a bargain (of course, you
> would have to use a lot of tapes to recoup the original $130K investment -- that
> does tend to put off quite a few people).

Comparing a single cart vs some other cart is not useful without 
considering size and cost. Either way, your statement was incorrect 
vs DLT. A DLT4 cart is $54. Check pricewatch. LTO are worse per GB 
than DLT. Ampex DST are so esoteric as to be relegated to the
companies where money is not much of a problem. I've used them 
though on Sun's and RS/6000's. Not exactly a standard tape drive 
interface so it's unlikely to attach to a Linux box. Also, Ampex's 
site says 330GB per tape, not 660GB.

> As I mentioned in my original response, it very much depends how much you are
> willing to spend, how much capacity you need, and how long your backup window
is.
> Other factors also come into play -- how many times can a tape be *reliably*
> reused, and the overall reliability of the drive.  MTBF figures are usually
quoted
> by the manufacturer, often using the technical "finger in the air" method of
> measurement.
> 

True. Pretty much ignore manufacturer MTBF because it's not possible 
to really know it, except on long established drives, like DLT's and
8mm.

> BTW, I think my eyeballs are just fine, thank you.
> 

OK. Try looking at pricewatch or your favorite pricing site before 
quoting prices next time.

> Regards,
> 
> Paul Bunn, UltraBac.com, 425-644-6000
> Microsoft MVP - WindowsNT/2000
> http://www.ultrabac.com
> 
> 
> -----Original Message-----
> From: W Bauske [mailto:wsb@paralleldata.com]
> Sent: Monday, March 26, 2001 1:03 PM
> To: axp-list@redhat.com
> Subject: Re: OT: tape backup
> 
> Paul Bunn wrote:
> >
> > Ecrix VXA-1 media is around $65 -- much more expensive that 4mm media, a
little
> > cheaper that AIT/DLT/M2 media.
> >
> 
> You better get new eyeballs. DLT is cheaper as is M2 per GB.
> I don't use AIT so I won't comment but a simple search on
> pricewatch will tell the true picture. If you want the best
> deal on $$/GB, use CD-R, then 8mm 5GB.