Subject: Re: Quirky SCSI drives
To: John F. Woods <>
From: Jason Thorpe <>
List: current-users
Date: 03/02/1996 22:41:13
On Sat, 2 Mar 1996 23:22:42 -0500 (EST) 
 "John F. Woods" <> wrote:

 > Speaking of the SCSI drive quirks table, I happen to have both a
 > quirky tape drive (who's the right person to tell of these?  Or is
 > send-pr the right path?), and a question.  The tape drive is a CIPHER
 > ST150S2/90 rev 2.2Q drive (QIC-150, pretty old and no doubt out of
 > production), and the question is:

send-pr is good for this...

 > What modern drives actually DO respond usefully to nonzero SCSI
 > logical units?  (I happen to have an OMTI-20D SASI adapter which would
 > handle two ST-506 disks and a QIC-02 tape drive (and I think a floppy,
 > but I don't remember) on separate LUNs, but I thought that most modern
 > SCSI equipment was all gadgets with builtin controllers that only
 > respond to LUN 0 (at best ;-).  While I suppose a RAID array might
 > usefully assign the nonzero LUNs to individual component drives (at
 > least for arrays of less than 7 disks), I don't know of any other
 > really obvious uses in modern equipment for multiple LUNs.

RAID boxes do the multiple-LUN thing...I think I heard that the Pioneer 
6-disc CD changers are LUN-oriented, too...

 > Perhaps "does something useful with LUNs" ought to be the ``quirk'',
 > rather than "screws up on LUNs"?  While it's sad to ``marginalize'' a
 > properly-designed drive, this would certainly reduce the frequency
 > with which that table has to be updated...

Dealing with LUNs is part of the SCSI standard, and devices that don't 
deal with LUNs properly don't strictly follow the standard.  It seems 
backwards to me to flip the semantics of LUN quirks around...

Jason R. Thorpe                             
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