From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: Converting RAID5 to RAID0 Date: Mon, 1 Sep 2014 08:31:37 +1000 Message-ID: <20140901083137.4772c8c5@notabene.brown> References: Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; boundary="Sig_/oj=7q2VpKcml=Expl.WCAFX"; protocol="application/pgp-signature" Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Mike Muratet Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids --Sig_/oj=7q2VpKcml=Expl.WCAFX Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Sun, 31 Aug 2014 12:43:26 +0000 (UTC) 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? 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=3D0 --raid-disks=3D2 will tell you that you need a backup file, so mdadm /dev/md0 --grow --level=3D0 --raid-disks=3D2 --backup-file=3D/root/= backup will work... but will leave you with a degraded RAID4. So just run that sa= me command again to finish the job. NeilBrown >=20 > There are no data on the disk. Is there a way to start over? >=20 > Cheers >=20 > Mike >=20 > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html --Sig_/oj=7q2VpKcml=Expl.WCAFX Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIVAwUBVAOiSTnsnt1WYoG5AQJefxAAjOEmb8AuzBzY7kQYTrfSxaSA+uHd6wQU 6aJGlHmBUVuifi4GmGKHHhoCDkffNpYxb3ga99kHHYLtijzLomQLsOGSmRc9PQzI 5mEK8ZD1XiT0hbyNOHq+uwLKOh6bncRH15KWPviabqMCllKMIzYGF6hz36NlrBji Rqhd1sCmjNBKHF5YL923ZvWo87ZBKpcgWUZosZzTM1Ae2I68N0PYisQYaxALV7MO miFFt8l0ysjJ9COm7iyJ784HbGyg5CXBT813+n3xRRyYjhEPxbvuMA1ozQNikanH c4Flo96zTCM1+myZ1p2Ov56OrGtKQzeWkenZPCoD467m7kfw1f954gm1HFeRg35i uZ00cgrwmSWf8Ym+xS1JkxEWpZfn0hN6wrPQRUbykJD1sv69an1qw2/j80kSB7Li eZM5Aj1+LW6DtWcd+1JiQlmcjybrpXs+o0h+u775moWFC/j4eHlOixv6PWG9PKrJ M7urlt6zIdO6flMK6lWlhN6eVmI1XVjFodR4KeMyD9xNJqLw3EIDVN74BQsg4X5k byBI+7RBzz8NYUfCx6SLeiBNoC3oEJ2EsayKGaci1pRnii6ROvwxeSlLymXXBfPm IAWRixf7Uq3b+d0yge2Tv/n7+N3a+EqYmU3ISxGMWDZBEFMn2cx9AaqzApz8CCpL HhmKDZplqJU= =MXGZ -----END PGP SIGNATURE----- --Sig_/oj=7q2VpKcml=Expl.WCAFX--