From: Neil Brown <neilb@suse.de>
To: Bill Davidsen <davidsen@tmr.com>
Cc: Linux RAID <linux-raid@vger.kernel.org>
Subject: Re: Another RAID level migration question
Date: Fri, 10 Aug 2007 11:55:45 +1000 [thread overview]
Message-ID: <18107.50593.330335.913673@notabene.brown> (raw)
In-Reply-To: message from Bill Davidsen on Thursday August 9
On Thursday August 9, davidsen@tmr.com wrote:
> I have an array on two drives which was set up as a RAID-0, because I
> needed the space and performance. Now I have another identical drive,
> ideally I would like to get to RAID-5, but I don't think that is going
> to fly, so how about RAID-4? I could create with a missing parity drive,
> then add the drive and see if it will rebuild.
>
> I hope to test this using loop devices, but time is fairly short right now.
Providing the two drives are exactly the same size (which rounded down
to a multiple of 64K), this will work. The parity drive is the last
in the list so
mdadm -C /dev/mdX -l4 -n3 -c WHATEVER /dev/sda1 /dev/sdb1 missing
is the sort of thing you want.
NeilBrown
prev parent reply other threads:[~2007-08-10 1:55 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-08-09 21:46 Another RAID level migration question Bill Davidsen
2007-08-10 1:55 ` Neil Brown [this message]
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