Dear all, since long I am using my raid6 with perfects results and now I am asking kindly for help. My raid6 consisting of 7 * 500GB became to small, so I decided to upgrade with 2 * 1TB-drives (sda and sdb) and use striping for the old-drives (sd[c-i]) to become 1TB as well. The resulting new raid6 is md10. keeper:/home/behn# cat /proc/mdstat Personalities : [raid6] [raid5] [raid4] [multipath] [faulty] [raid0] md10 : active raid6 md3p1[6] md2p1[3] md1p1[2] sdb1[1] sda1[0] 3907039232 blocks super 1.0 level 6, 64k chunk, algorithm 2 [6/4] [UUUU__] [>....................] recovery = 0.0% (434432/976759808) finish=15374.9min speed=1057K/sec md3 : active raid0 sdd1[0] sdc1[1] 976767872 blocks 64k chunks md2 : active raid0 sde1[0] sdf1[1] 976767872 blocks 64k chunks md1 : active raid0 sdh1[0] sdi1[1] 976767872 blocks 64k chunks Of course that means creating and assembling of the new m10 was just fine, however due to money the 6th drive was declared missing: keeper:/home/behn# mdadm --create /dev/md10 --name=10 --metadata=1.0 --level=6 --raid-devices=6 /dev/sda1 /dev/sdb1 /dev/md[1-3]p1 missing mdadm: /dev/sda1 appears to be part of a raid array: level=raid6 devices=5 ctime=Fri Apr 23 00:03:31 2010 mdadm: /dev/sdb1 appears to contain an ext2fs file system size=-1096252032K mtime=Fri Apr 23 11:33:16 2010 mdadm: /dev/sdb1 appears to be part of a raid array: level=raid6 devices=5 ctime=Fri Apr 23 00:03:31 2010 Continue creating array? y mdadm: array /dev/md10 started. I just created the ext3-fs on the newly created md10 and tuned it: keeper:/home/behn# fdisk -l /dev/md10 WARNING: The size of this disk is 4.0 TB (4000808173568 bytes). DOS partition table format can not be used on drives for volumes larger than (2199023255040 bytes) for 512-byte sectors. Use parted(1) and GUID partition table format (GPT). Disk /dev/md10: 4000.8 GB, 4000808173568 bytes 2 heads, 4 sectors/track, 976759808 cylinders Units = cylinders of 8 * 512 = 4096 bytes Disk identifier: 0xfc0ca3a2 Device Boot Start End Blocks Id System /dev/md10p1 1 536870911 2147483642 83 Linux keeper:/home/behn# tune2fs -m 1 -j /dev/md10p1 tune2fs 1.41.11 (14-Mar-2010) Setting reserved blocks percentage to 1% (5368709 blocks) Creating journal inode: done This filesystem will be automatically checked every 27 mounts or 180 days, whichever comes first. Use tune2fs -c or -i to override. Solong, until this point all was perfectly fine to me. I copied some large stuff to md10 and the array looked good: keeper:/home/behn# mdadm --detail /dev/md10 /dev/md10: Version : 1.00 Creation Time : Fri Apr 23 20:18:56 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 : 5 Persistence : Superblock is persistent Update Time : Fri Apr 23 20:21:04 2010 State : active, degraded, recovering Active Devices : 4 Working Devices : 5 Failed Devices : 0 Spare Devices : 1 Chunk Size : 64K Rebuild Status : 0% complete Name : keeper:10 (local to host keeper) UUID : 3c35cc46:f7afe8be:5ce1aa14:73a5567c Events : 3 Number Major Minor RaidDevice State 0 8 1 0 active sync /dev/sda1 1 8 17 1 active sync /dev/sdb1 2 259 0 2 active sync /dev/md1p1 3 259 1 3 active sync /dev/md2p1 6 259 2 4 spare rebuilding /dev/md3p1 5 0 0 5 removed here comes my pain now: ======================== But once I stopped the array, I can't reassmble it: ==================================================== keeper:/home/behn# mdadm --assemble /dev/md10 /dev/sda1 /dev/sdb1 /dev/md[1-3] mdadm: cannot open device /dev/sda1: Device or resource busy mdadm: /dev/sda1 has no superblock - assembly aborted Can please someone suggest how to continue here please? I have not changed hw and even in addition the /dev/sda and /dev/sdb worked like a charm in a raid1 before I decided to create the nested md10: I am using this as mdadm.conf keeper:/home/behn# mdadm --detail --scan DEVICE /dev/sd[a-z] ARRAY /dev/md1 metadata=0.90 UUID=5ece961d:9f6b8d08:3e3ade9f:30eaa984 ARRAY /dev/md2 metadata=0.90 UUID=9b6fc6e1:d1798014:3e3ade9f:30eaa984 ARRAY /dev/md3 metadata=0.90 UUID=2eec48f7:45b2e76a:3e3ade9f:30eaa984 ARRAY /dev/md10 metadata=1.00 spares=1 name=keeper:10 UUID=3c35cc46:f7afe8be:5ce1aa14:73a5567c many thanks for your help christian -- GRATIS für alle GMX-Mitglieder: Die maxdome Movie-FLAT! Jetzt freischalten unter http://portal.gmx.net/de/go/maxdome01 -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html