From: David Greaves <david@dgreaves.com>
To: Neil Brown <neilb@suse.de>
Cc: Hubert Verstraete <hubskml@free.fr>, linux-raid@vger.kernel.org
Subject: Re: RAID5 losing initial synchronization on restart when one disk is spare
Date: Thu, 12 Jun 2008 09:03:56 +0100 [thread overview]
Message-ID: <4850D86C.70402@dgreaves.com> (raw)
In-Reply-To: <18512.25477.431367.952164@notabene.brown>
Neil Brown wrote:
> When writing to the array, the new parity block will sometimes be
> calculated assuming that it was previously correct. If all updates to
> a particular parity block are of this sort, then it will still be
> incorrect when you lose a drive, and data recovered based on that
> parity block will be incorrect.
>
> Until you lose a drive, it will have no visible effect.
There is a slight chance that this happened to me recently - would a
echo check > /sys/block/mdX/md/sync_action
detect this?
and would
echo repair > /sys/block/mdX/md/sync_action
fix it?
David
next prev parent reply other threads:[~2008-06-12 8:03 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-06-04 10:13 RAID5 losing initial synchronization on restart when one disk is spare Hubert Verstraete
2008-06-10 11:57 ` Hubert Verstraete
2008-06-10 22:56 ` Dan Williams
2008-06-11 9:27 ` Hubert Verstraete
2008-06-11 23:40 ` Neil Brown
2008-06-11 14:44 ` Hubert Verstraete
2008-06-11 23:38 ` Neil Brown
2008-06-12 13:05 ` Hubert Verstraete
2008-06-12 16:59 ` Dan Williams
2008-06-12 18:11 ` Hubert Verstraete
2008-06-11 23:45 ` Neil Brown
2008-06-12 8:03 ` David Greaves [this message]
2008-06-12 17:01 ` Dan Williams
2008-06-12 9:12 ` Hubert Verstraete
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