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From: "Michał Sawicz" <michal@sawicz.net>
To: linux-raid <linux-raid@vger.kernel.org>
Subject: Re: Building RAID5 w/o a Hot Spare
Date: Wed, 27 Jan 2010 15:46:17 +0100	[thread overview]
Message-ID: <1264603577.1928.4.camel@test.apertos.eu> (raw)
In-Reply-To: <d80f793f1001270626s3ec1791ma0b5da4b87a31e34@mail.gmail.com>

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Dnia 2010-01-27, śro o godzinie 09:26 -0500, Carlos Williams pisze:
> I am building a Linux system which has 4 identical 'fd' partitions on
> each of the 4 drives. I don't want to use the 4th partition or disk if
> you would like to call it as a 'hot spare'. I would like to span the
> entire array over the 4 drives. My question is does my command look
> correct for doing so?

I'm not sure I understand what you want to achieve. A 'spare' disk is
one that isn't used until any of the other fail, then the spare replaces
the failed one. The term 'hot spare' is used to identify a disk that is
a mirror of one of the other drives, but there's no support for that in
Linux Software-RAID.

> mdadm --create /dev/md0 --level=5 --raid-devices=4 /dev/sda2 /dev/sdb2
> /dev/sdc2 /dev/sdd2 

This will create a RAID5 array of 4 devices, yes. Capacity will be 3 x
sd?2. Failure of any one of those disks will not harm the data.

-- 
Cheers
Michał (Saviq) Sawicz


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  reply	other threads:[~2010-01-27 14:46 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-01-27 14:26 Building RAID5 w/o a Hot Spare Carlos Williams
2010-01-27 14:46 ` Michał Sawicz [this message]
2010-01-27 14:53   ` Robin Hill
2010-02-01 21:45   ` Bill Davidsen
     [not found] ` <1264603005.1928.3.camel@test.apertos.eu>
     [not found]   ` <d80f793f1001270641k29430f12r59b9f9fa02966ea0@mail.gmail.com>
2010-01-27 14:49     ` Carlos Williams
2010-01-27 15:34     ` Michał Sawicz
2010-01-27 15:14 ` Goswin von Brederlow
2010-01-27 15:15   ` Carlos Williams
2010-01-27 20:46     ` Goswin von Brederlow

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