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From: Neil Brown <neilb@suse.de>
To: Guy Watkins <linux-raid@watkins-home.com>
Cc: 'Greg Freemyer' <greg.freemyer@gmail.com>,
	'Mark Knecht' <markknecht@gmail.com>,
	'Linux-RAID' <linux-raid@vger.kernel.org>
Subject: Re: What RAID type and why?
Date: Sun, 7 Mar 2010 13:21:13 +1100	[thread overview]
Message-ID: <20100307132113.7e2c95b6@notabene.brown> (raw)
In-Reply-To: <9089562724D84B3C858E337F202FF550@m5>

On Sat, 06 Mar 2010 18:17:44 -0500
"Guy Watkins" <linux-raid@watkins-home.com> wrote:

> } 
> } At a minimum I would build a 3-disk raid 6.  raid 6 does a lot of i/o
> } which may be a problem.
> 
> If he only needs 3 drives I would recommend RAID1.  Can still loose 2 drives
> and you don't have the RAID6 I/O overhead.
> 

and as md/raid6 requires at least 4 drives, RAID1 is not just the best
solution to survive two failures on a 3-device array, it is the only solution.

NeilBrown

  parent reply	other threads:[~2010-03-07  2:21 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-06 22:02 What RAID type and why? Mark Knecht
2010-03-06 22:33 ` Greg Freemyer
2010-03-06 23:05   ` Mark Knecht
2010-03-07  0:38     ` Keld Simonsen
2010-05-10 15:20     ` Matt Garman
2010-05-10 15:34       ` Mark Knecht
2010-03-06 23:17   ` Guy Watkins
2010-03-06 23:51     ` Mark Knecht
2010-03-08 20:05       ` Bill Davidsen
2010-03-06 23:56     ` Michael Evans
2010-03-07  2:21     ` Neil Brown [this message]
2010-03-07  8:06       ` Keld Simonsen
2010-03-07  8:10         ` Guy Watkins
2010-03-07  8:22           ` 'Keld Simonsen'
2010-03-07 10:09             ` Michael Evans
2010-03-07 12:52       ` Goswin von Brederlow
2010-03-07 20:40         ` Michael Evans
2010-03-10 17:47           ` Goswin von Brederlow
2010-03-11 10:44             ` Michael Evans
2010-03-06 23:03 ` Asdo

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