Message-ID: <4323F8E9.3010506@eyal.emu.id.au>
Date: Sun, 11 Sep 2005 19:29:13 +1000
From: Eyal Lebedinsky <eyal@eyal.emu.id.au>
Organization: Eyal at Home
User-Agent: Debian Thunderbird 1.0.2 (X11/20050817)
MIME-Version: 1.0
To: Lennert Buytenhek <buytenh@wantstofly.org>
CC: Neil Brown <neilb@cse.unsw.edu.au>, linux-kernel@vger.kernel.org
Subject: Re: read-from-all-disks support for RAID1?
References: <20050910123902.GA9461@xi.wantstofly.org>
In-Reply-To: <20050910123902.GA9461@xi.wantstofly.org>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1061
Lines: 30

Lennert Buytenhek wrote:
> (please CC on replies)
> 
> Hi!
> 
> I recently had a case where one disk in a two-disk RAID1 array went
> subtly bad, effectively refusing to write to certain sectors without
> reporting an error.  Basically, parts of the disk went undetectably
> read-only, causing file system corruption that wouldn't go away after
> fsck, and all kinds of other fun.
> 
> Would it be hard/wise to add an option for RAID1 mode to read from all
> devices on a read, and report an error to syslog or simply return an
> I/O error if there is a mismatch?  (Or use majority voting and tell
> people to use 3-disk RAID1 arrays from now on ;-)
> 
> 
> thanks,
> Lennert

Would a two-disk raid-5 not do just what you want?

-- 
Eyal Lebedinsky (eyal@eyal.emu.id.au) <http://samba.org/eyal/>
	attach .zip as .dat
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/