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Subject: Re: SCSI error code 83 and 84, medium errors
To: taob@io.org (Brian Tao)
Date: Mon, 26 Feb 1996 22:02:09 -0800 (PST)
From: "JULIAN Elischer" <julian@ref.tfs.com>
Cc: freebsd-hackers@freebsd.org
In-Reply-To: <Pine.BSF.3.91.960226232956.3793F-100000@zip.io.org> from "Brian Tao" at Feb 27, 96 00:06:09 am
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The AWRE and ARRE bits only replace a block if it can recover the data.
one way of doing this it to write to the block, because the drive figures
(correctly) that if you are over-writing the block, the old data doesn't
matter and can be considered recovered and deleted..

> 
> sd8(ncr2:2:0): error code 84
> sd8(ncr2:2:0): MEDIUM ERROR info:1af3b asc:14,1 Record not found field replaceable unit: 2
[...]
> have gone away after a newfs (I tested it by dd'ing /dev/zero to a
> file on that partition, filling it up, then reading the file back in).
> The disk is a Seagate Medallist 1GB SCSI-2 drive, the last drive on
> the third NCR53c810 controller.  Is there anything I should be
> worried about now?
> 

keep a spare drive handy?