Skip site navigation (1)Skip section navigation (2)
Date:      Fri, 7 May 1999 21:08:19 +0200 (CEST)
From:      Wilko Bulte <wilko@yedi.iaf.nl>
To:        karl@Denninger.Net (Karl Denninger)
Cc:        mjacob@feral.com, darrylo@sr.hp.com, freebsd-scsi@FreeBSD.ORG
Subject:   Re: Question - Onstream SCSI Streamer
Message-ID:  <199905071908.VAA83160@yedi.iaf.nl>
In-Reply-To: <19990507133900.A317@Denninger.Net> from Karl Denninger at "May 7, 1999  1:39: 0 pm"

next in thread | previous in thread | raw e-mail | index | archive | help
As Karl Denninger wrote ...
> On Fri, May 07, 1999 at 11:32:15AM -0700, Matthew Jacob wrote:

> > > > >      If you're feeling brave and lucky, OnStream is selling "new"
> > > > > internal Quantum DLT-2000XT's for $649 (15GB capacity, uncompressed	).
> > > > > Note that these are "brand new" obsolete drives.  You'd better read the
> > > > > fine print (especially on warranty, shipping, and "defective products"),
> > > > > but check out:
> > > > 
> > > > I would not recommend the XT given the media incompatibilities they've
> > > > been known to have.
> > > 
> > > The XTs are fine - but they cannot read or write tapes written on a 
> > > DLT 4000 or 7000.

They can read DLT4000 written tapes iff these are on CompactapeIII or 
CompacTapeIIIxt tapes. They can't write/read the Compactape IV tapes, these
are only for DLT[47]000 drives.

> > > second-sourced.  As such you're going to get positively raped on the 
> > > media cost since there is no competition (no Fuji tapes, for example).
> > > 
> > > I had two of these at MCS - they were rock-solid and reliable.  However,
> > > unless you can reliably source media they're going to be trouble down the
> > > road.
> > 
> > I had several at Legato. By mistake an XT tape placed into a 2000
> > destroyed it.

The tape I guess, not the drive.

> Well, yes.  The XT tapes are both thinner and longer than the regular 
> 2000-series DLT tapes, and the 2000-series drives CANNOT handle the 
> thinner and longer media.
> 
> DLT in general is *forward* compatible, but not *backward* compatible.

Not true, the TZ87 and older drives (yes, the DEC ones, before they
sold the tape & disk stuff to Quantum) can even read/write TK50 media
aka Compactape II. A whopping 90Mb / cartridge.

The DLT2000 is equivalent to a TZ87N (note the N) and can't do TK50
tapes.

TZ87 drives are second hand several hunderd $ more expensive than TZ87N.
The heads of the TZ87 are speced / tested to much narrower tolerances
to be able to do TK50. Some people are really willing to pay top $
to get the genuine TZ87 ;-)

> I have NOT tried putting a 2000-XT tape in a DLT-4000 unit, and have
> absolutely no idea if that is safe or not.  If its not then the drive
> is a dead end, which could be bad.

Works like a charm and is OK. My TZ88 aka DLT4000 is fed with a diet of
Compactape III and IIIxt tapes.

> One of the items that makes these new "Onstream" drives so attractive is
> the price.  $500 for the drive is damn good, and with media about $1/Gb
> its quite competitive.  The 50G version of the same drive, due out sometime
> this second quarter can handle an "extra length" cartridge - but is also
> backward compatible for both read an write.
> 
> The Onstreams are also about as fast as a DLT 4000 (but not as fast as the
> DLT 7000) in terms of raw I/O bitrate, and their media is less expensive.

Ever tried to keep a DLT7000 streaming? Better fix the 64kbyte physio
bottleneck before trying.

Groeten / Cheers,

|   / o / /  _  	 Arnhem, The Netherlands	- Powered by FreeBSD -
|/|/ / / /( (_) Bulte 	 WWW  : http://www.tcja.nl 	http://www.freebsd.org


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-scsi" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199905071908.VAA83160>