From: NeilBrown <neilb@suse.de>
To: Mike Muratet <muratetm@gmail.com>
Cc: linux-raid@vger.kernel.org
Subject: Re: Converting RAID5 to RAID0
Date: Mon, 1 Sep 2014 08:31:37 +1000 [thread overview]
Message-ID: <20140901083137.4772c8c5@notabene.brown> (raw)
In-Reply-To: <loom.20140831T143354-68@post.gmane.org>
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On Sun, 31 Aug 2014 12:43:26 +0000 (UTC) Mike Muratet <muratetm@gmail.com>
wrote:
> I am doing some experiments with mdadm to combine two 1TB disks into a RAID
> array. I used fdisk to create the partitions and mdadm to create a two disk
> RAID5 array. I would like to have more space and I can live without
> redundancy. I searched the man pages and boards for a way to do that and found:
>
> $ sudo mdadm /dev/md0 -f /dev/sdd
> mdadm: set /dev/sdd faulty in /dev/md0
> $ sudo mdadm /dev/md0 -r /dev/sdd
> mdadm: hot removed /dev/sdd from /dev/md0
> $ sudo echo raid0 > /sys/block/md0/md/level
>
> -bash: /sys/block/md0/md/level: Permission denied
>
> which was not the result I expected.
>
> Is it possible to convert RAID5 to RAID0?
Presumably you mean to convert a 2-device RAID5 to q 2-device RAID0, thus
doubling the amount of space.
mdadm /dev/md0 --grow --level=0 --raid-disks=2
will tell you that you need a backup file, so
mdadm /dev/md0 --grow --level=0 --raid-disks=2 --backup-file=/root/backup
will work... but will leave you with a degraded RAID4. So just run that same
command again to finish the job.
NeilBrown
>
> There are no data on the disk. Is there a way to start over?
>
> Cheers
>
> Mike
>
> --
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next prev parent reply other threads:[~2014-08-31 22:31 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-08-31 12:43 Converting RAID5 to RAID0 Mike Muratet
2014-08-31 17:13 ` Robin Hill
2014-08-31 22:31 ` NeilBrown [this message]
2014-09-10 16:15 ` Add disks and convert level 0 to level 5 Michael Muratet
2014-09-11 0:27 ` NeilBrown
2014-09-17 14:59 ` Michael Muratet
2014-09-17 15:15 ` Robin Hill
2014-09-11 7:27 ` Robin Hill
-- strict thread matches above, loose matches on Subject: below --
2014-09-01 14:10 Converting RAID5 to RAID0 Michael Muratet
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