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: Tue, 15 Sep 2009 18:05:53 +0000
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On Tue, 2009-09-15 at 20:02 +0300, Majed B. wrote:
> Out of curiosity, how will you find the sectors/blocks that
> reconstruct a certain bad sector? Is the data spread to the same block
> number on all disks?

Yes. It's a byte-level operation, actually.

The only part that's moderately tricky is, on RAID6, to determine which
partition the Q drive is. Fortunately, mdadm already contains (almost)
all the necessary logic.