From mboxrd@z Thu Jan 1 00:00:00 1970 From: "christian (private)" Subject: corrupted UUID or superblock prohibits assemby of prior created raid6 Date: Sun, 02 May 2010 09:33:03 +0200 Message-ID: <4BDD2AAF.9070800@gmx.de> 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 Mailing List List-Id: linux-raid.ids Dear all, I am kindly asking for help please. The issue is the following: I am creating an mdadm raid6-array and after successful sync all looks fine. However after rebooting the raid6 refuses to start due to missing disks. To my understanding this is all related to incorrect UUID's, however I am kindly asking the experts to have alook into it: The error-message (similiar for all my 1TB-drives /dev/sd[abi]1) ====================================== keeper:~# mdadm --assemble /dev/md10 /dev/sd[abi]1 /dev/md[1-3] mdadm: cannot open device /dev/sda1: Device or resource busy mdadm: /dev/sda1 has no superblock - assembly aborted systems basics ========== keeper:~# uname -a Linux keeper 2.6.30-2-amd64 #1 SMP Fri Dec 4 03:31:05 UTC 2009 x86_64 GNU/Linux distro: debian testing ii mdadm 3.0.3-2 tool to administer Linux MD arrays (software ii e2fslibs 1.41.11-1 ext2/ext3/ext4 file system libraries ii e2fsprogs 1.41.11-1 ext2/ext3/ext4 file system utilities creating the array (hint, after reboot its /dev/sd[abi]1 instead of /dev/sdb1 /dev/sdc1 /dev/sdi1) =========================================================== 387 mdadm --create /dev/md10 --name=10 --metadata=1.0 --level=6 --raid-devices=6 /dev/sdb1 /dev/sdc1 /dev/sdi1 /dev/md[1-3] the array gets created - verifying after resync without rebooting ========================================= /dev/md10: Version : 1.00 Creation Time : Sat May 1 19:41:39 2010 Raid Level : raid6 Array Size : 3907039232 (3726.04 GiB 4000.81 GB) Used Dev Size : 976759808 (931.51 GiB 1000.20 GB) Raid Devices : 6 Total Devices : 6 Persistence : Superblock is persistent Update Time : Sun May 2 03:44:29 2010 State : active Active Devices : 6 Working Devices : 6 Failed Devices : 0 Spare Devices : 0 Chunk Size : 64K Name : keeper:10 (local to host keeper) *UUID : d9b9e76d:0113d173:39173474:7f43de08* Events : 35 Number Major Minor RaidDevice State 0 8 17 0 active sync /dev/sdb1 1 8 33 1 active sync /dev/sdc1 2 8 129 2 active sync /dev/sdi1 3 9 1 3 active sync /dev/md1 4 9 2 4 active sync /dev/md2 5 9 3 5 active sync /dev/md3 keeper:~# cat /proc/mdstat This is looking fine as well ================== Personalities : [raid6] [raid5] [raid4] [multipath] [faulty] [raid0] md10 : active raid6 md3[5] md2[4] md1[3] sdi1[2] sdc1[1] sdb1[0] 3907039232 blocks super 1.0 level 6, 64k chunk, algorithm 2 [6/6] [UUUUUU] md1 : active raid0 sdf1[0] sdg1[1] 976767872 blocks 64k chunks md2 : active raid0 sdh1[1] sda1[0] 976767872 blocks 64k chunks md3 : active raid0 sdd1[1] sde1[0] 976767872 blocks 64k chunks To my understanding all member-drives of md10 should have the same UUID, but after a reboot this is not any longer the case. Please notice that I created the array with "/dev/sd[bci]1 /dev/md[1-3]" and after reboot its /dev/sd[abi]1 and /dev/md[1-3]. But as you can see, the UUID's are not identical anyhow: ============================================================= keeper:~# blkid /dev/hda1: UUID="3A60F2845E1B3C0F" TYPE="ntfs" /dev/hda2: UUID="e9a9b276-0530-42eb-8317-cd3999ff8b90" TYPE="swap" /dev/hda3: UUID="738eeb2f-fae4-40a0-b0de-fc188837e44c" TYPE="ext3" /dev/sdb1: UUID="d9b9e76d-0113-d173-3917-34747f43de08" LABEL="keeper:10" TYPE="linux_raid_member" << looks good /dev/sdc1: UUID="f45cfa44-1770-7e1c-3e3a-de9f30eaa984" TYPE="linux_raid_member" LABEL="keeper:10" /dev/sdd1: UUID="f45cfa44-1770-7e1c-3e3a-de9f30eaa984" TYPE="linux_raid_member" LABEL="keeper:11" /dev/sde1: UUID="0805c25a-cf77-4fb6-3e3a-de9f30eaa984" TYPE="linux_raid_member" /dev/sdf1: UUID="0805c25a-cf77-4fb6-3e3a-de9f30eaa984" TYPE="linux_raid_member" /dev/sdg1: UUID="13d13245-3c7d-8682-3e3a-de9f30eaa984" TYPE="linux_raid_member" /dev/sdh1: UUID="13d13245-3c7d-8682-3e3a-de9f30eaa984" TYPE="linux_raid_member" /dev/sdi1: UUID="d9b9e76d-0113-d173-3917-34747f43de08" TYPE="linux_raid_member" LABEL="keeper:10" << looks good /dev/sda1: UUID="c6f73dbb-528d-aa64-3e3a-de9f30eaa984" TYPE="linux_raid_member" << should be *d9b9e76d:0113d173:39173474:7f43de08* /dev/md1: UUID="058e47cd-e3ff-0fb9-3e3a-de9f30eaa984" TYPE="linux_raid_member" << should be *d9b9e76d:0113d173:39173474:7f43de08* /dev/md2: UUID="058e47cd-e3ff-0fb9-3e3a-de9f30eaa984" TYPE="linux_raid_member" << should be *d9b9e76d:0113d173:39173474:7f43de08* /dev/md3: UUID="058e47cd-e3ff-0fb9-3e3a-de9f30eaa984" TYPE="linux_raid_member" << should be *d9b9e76d:0113d173:39173474:7f43de08* Can please anyone help me digging out whats going on here? What I can say, that if I create 2 * raid5 (/dev/sd[abi]1 and /dev/md[1-3]) instead of combining them into a single raid6, then all is perfect. Maybe I should say, that /dev/md[1-3] are 2* striped 500G disks and /dev/sd[abi]1 are 1TB drives. any help is very much appreciated. The next step I am doing is manually setting the UUID to have it matched... further more I thoughts setting the UUID manually could solve the issue keeper:~# tune2fs -U d9b9e76d-0113-d173-3917-34747f43de08 /dev/sda1 tune2fs 1.41.11 (14-Mar-2010) tune2fs: Filesystem revision too high while trying to open /dev/sda1 Couldn't find valid filesystem superblock. <<< does not look good to me keeper:~# fdisk -l /dev/sda Disk /dev/sda: 1000.2 GB, 1000204886016 bytes 255 heads, 63 sectors/track, 121601 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x00000000 Device Boot Start End Blocks Id System /dev/sda1 1 121601 976760001 83 Linux keeper:~# blkid /dev/sda keeper:~# blkid /dev/sda1 /dev/sda1: UUID="c6f73dbb-528d-aa64-3e3a-de9f30eaa984" TYPE="linux_raid_member" keeper:~# tune2fs -l /dev/sda1 tune2fs 1.41.11 (14-Mar-2010) tune2fs: Filesystem revision too high while trying to open /dev/sda1 Couldn't find valid filesystem superblock. Any idea why the superblock is giving me trouble here? many thanks christian