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From: "H. Peter Anvin" <hpa@zytor.com>
To: Goswin von Brederlow <goswin-v-b@web.de>
Cc: Nifty Fedora Mitch <niftyfedora@niftyegg.com>,
	linux-raid@vger.kernel.org
Subject: Re: Why do I need 4 disks for a raid6?
Date: Wed, 01 Apr 2009 09:09:57 -0700	[thread overview]
Message-ID: <49D391D5.1050509@zytor.com> (raw)
In-Reply-To: <87ljquemy3.fsf@frosties.localdomain>

Goswin von Brederlow wrote:
> 
> Actually the definition I read was that raid6 is like raid5 but
> allowing for 2 or more disks to fail without loss. So a 15 disks raid
> with 10 data blocks and 5 parity blocks per stripe would also be raid6.
> 

2 or more *arbitrary* disks.  You can't, say, have two RAID-5s and call
the combination a RAID-6, because they're not all there.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.


      reply	other threads:[~2009-04-01 16:09 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-03-17 19:12 Why do I need 4 disks for a raid6? Goswin von Brederlow
2009-03-18  3:41 ` david.geib
2009-03-18  9:50   ` Goswin von Brederlow
2009-03-18 18:12     ` david.geib
2009-03-18 12:18 ` Andre Noll
     [not found]   ` <49C0EA5F.9070901@vshift.com>
2009-03-18 12:35     ` Andre Noll
2009-03-18 14:08       ` Goswin von Brederlow
2009-03-18 14:26         ` Robin Hill
2009-03-18 18:48           ` Goswin von Brederlow
2009-04-01 16:08   ` H. Peter Anvin
2009-04-01 17:47     ` Andre Noll
2009-04-01 20:36       ` H. Peter Anvin
2009-04-01 18:07     ` Goswin von Brederlow
2009-04-01 19:05       ` H. Peter Anvin
2009-03-19 23:35 ` Neil Brown
2009-03-20 10:20   ` Goswin von Brederlow
2009-03-23 20:20   ` Nifty Fedora Mitch
2009-03-24 19:32     ` Goswin von Brederlow
2009-04-01 16:09       ` H. Peter Anvin [this message]

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