From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bart Kus Subject: Online RAID1 -> RAID10 migration? Date: Fri, 25 Nov 2011 23:48:47 -0800 Message-ID: <4ED099DF.2010007@bartk.us> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Hello, I'd like to know if it's possible to do online RAID1 -> RAID10 migration with md. I ran a little experiment and it seems my approach doesn't work: jo test # mdadm --detail /dev/md7 /dev/md7: Version : 1.0 Creation Time : Fri Nov 25 23:29:37 2011 Raid Level : raid1 Array Size : 51188 (50.00 MiB 52.42 MB) Used Dev Size : 51188 (50.00 MiB 52.42 MB) Raid Devices : 2 Total Devices : 4 Persistence : Superblock is persistent Update Time : Fri Nov 25 23:33:55 2011 State : clean Active Devices : 2 Working Devices : 4 Failed Devices : 0 Spare Devices : 2 Name : jo.bartk.us:TEST (local to host jo.bartk.us) UUID : 5c6e806a:d91b8007:dce490aa:1442d468 Events : 19 Number Major Minor RaidDevice State 0 7 0 0 active sync /dev/loop0 1 7 1 1 active sync /dev/loop1 2 7 2 - spare /dev/loop2 3 7 3 - spare /dev/loop3 jo test # mdadm -G /dev/md7 -n 4 -l 10 mdadm: /dev/md7: could not set level to raid10 jo test # dmesg | tail -1 md: md7: raid10 would not accept array Any advice on how to pull this off? Is it even possible? Can it be implemented? My root device is on RAID1 and I'd like to move it to RAID10 to get some write/read speed benefit. Thanks, --Bart