From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Hill Subject: Re: Converting RAID5 to RAID0 Date: Sun, 31 Aug 2014 18:13:27 +0100 Message-ID: <20140831171327.GB25561@cthulhu.home.robinhill.me.uk> References: Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="O5XBE6gyVG5Rl6Rj" Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Mike Muratet Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids --O5XBE6gyVG5Rl6Rj Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun Aug 31, 2014 at 12:43:26PM +0000, Mike Muratet wrote: > I am doing some experiments with mdadm to combine two 1TB disks into a RA= ID > array. I used fdisk to create the partitions and mdadm to create a two di= sk > 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: >=20 > $ 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 >=20 > -bash: /sys/block/md0/md/level: Permission denied >=20 > which was not the result I expected. >=20 > Is it possible to convert RAID5 to RAID0? >=20 It should be, yes. I'd use "mdadm --grow --level=3D0" rather than direct interaction with sysfs though. You may need to add "--force" in order to get a 1-disk RAID0 array though (it's mentioned as being required for create anyway). > There are no data on the disk. Is there a way to start over? >=20 Sure. Just stop the arrays (mdadm -S /dev/md0) and then run a new create command. You'll be prompted about an existing array (and filesystem, if you'd created that) but can continue to overwrite with the new settings. Cheers, Robin --=20 ___ =20 ( ' } | Robin Hill | / / ) | Little Jim says .... | // !! | "He fallen in de water !!" | --O5XBE6gyVG5Rl6Rj Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iEYEARECAAYFAlQDV7UACgkQShxCyD40xBJeFACgkYVVvIsL2V1l45U3q6X62WM6 IIIAoKdeVzysHTwINcNYeQsTt+gbB9Bq =drtp -----END PGP SIGNATURE----- --O5XBE6gyVG5Rl6Rj--