From mboxrd@z Thu Jan  1 00:00:00 1970
From: Matthias Urlichs <matthias@urlichs.de>
Subject: Re: Re-map disk sectors in userspace when rewriting after read
 errors
Date: Wed, 16 Sep 2009 11:44:26 +0200
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To: "Majed B." <majedb@gmail.com>
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On Wed, 2009-09-16 at 12:31 +0300, Majed B. wrote:
> I have a question which would probably sound stupid: If I have a bad
> blocks output file from dd_rescue, can I reconstruct a bad sector's
> data by reading the same sector from all disks (using dd if=/dev/sdx
> of=./bbfix_#number bs=512 count=1 skip=bb_number-1), then run an
> normal XOR operation, write zeros to the bad block to force sector
> remap, then dd the XOR output to the said sector?

Well, of course. Assuming that the disk's sector remap works, which was
my problem, and that we're talking about RAID5.