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Date: Fri, 6 Sep 1996 18:46:59 +0200 (MET DST)
Message-Id: <199609061646.SAA16609@x14.mi.uni-koeln.de>
From: Stefan Esser <se@zpr.uni-koeln.de>
To: Torbjorn Granlund <tege@matematik.su.se>
Cc: Stefan Esser <se@zpr.uni-koeln.de>, Sean Eric Fagan <sef@kithrup.com>,
        bde@zeta.org.au, hackers@FreeBSD.org
Subject: Re: forwarded 
In-Reply-To: <199609052043.WAA20334@insanus.matematik.su.se>
References: <199609051953.VAA01686@x14.mi.uni-koeln.de>
	<199609052043.WAA20334@insanus.matematik.su.se>
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Torbjorn Granlund writes:
 >   Hmmm, what's the length of the SCSI cable ?  What quality is it ?
 > 
 > I don't know if the quality is OK, but it is surely not more than 0.75
 > metres.

Well, this should be short enough ...

 >   I assume you know, that Ultra-SCSI tolerates at most 1.5 (5ft.) of
 >   high-quality cable, total.
 > 
 > According to the Ultra docs I have, up to 6 metres should be OK.  (3 metres
 > if there are any non-ultra devices on the bus.)

The numbers I know are max. 3m with at 
most 4 devices (incl. controller) on the
SCSI bus, 1.5m else.

 >   Another (IMHO) open question is, whether FAST SCSI devices (like your DAT
 >   and CDROM) may be on a SCSI bus using 20MHz transfer rates. I'd be careful
 >   because of a perhaps too high load, and because they might become confused
 >   because of the too short strobes.
 > 
 > Possible, but the other devices were idle when the disk corruption took
 > place.

This wouldn't make a difference. I've seen
it happen ...

Regards, STefan