Re: No md superblock immediately after creating RAID 5 /dev/md0
From: <hidden>
Date: 2008-08-29 05:47:50
Hi Neil,
Sorry for the confusion. I mistyped the -C command in my initial email
(forgot the hot-spare) and thus the confusion.
Here is the full output from the top using copy/paste. Thank you in
advance for your help!!
root@localhost:~# fdisk -l
Disk /dev/sda: 2095 MB, 2095865856 bytes
65 heads, 62 sectors/track, 1015 cylinders
Units = cylinders of 4030 * 512 = 2063360 bytes
Disk identifier: 0x00000000
Device Boot Start End Blocks Id System
/dev/sda1 * 1 500 1007469 83 Linux
/dev/sda2 * 501 1015 1037725 83 Linux
Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x0b65bb81
Device Boot Start End Blocks Id System
Disk /dev/sdc: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x273d0b7e
Device Boot Start End Blocks Id System
Disk /dev/sdd: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x03cf614e
Device Boot Start End Blocks Id System
Disk /dev/sde: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0xa6b886bb
Device Boot Start End Blocks Id System
Disk /dev/sdf: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x65752a1a
Device Boot Start End Blocks Id System
Disk /dev/sdg: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x9f188135
Device Boot Start End Blocks Id System
Disk /dev/sdh: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0xc19605d4
Device Boot Start End Blocks Id System
Disk /dev/sdi: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x1e6c4f8e
Device Boot Start End Blocks Id System
Disk /dev/sdj: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0xd13edb81
Device Boot Start End Blocks Id System
Disk /dev/sdk: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x5bbd83b9
Disk /dev/sdk doesn't contain a valid partition table
Disk /dev/sdl: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0xebcdc998
Device Boot Start End Blocks Id System
Disk /dev/sdm: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0xd90b43ff
Device Boot Start End Blocks Id System
root@localhost:~#
root@localhost:~# cat /etc/mdadm.conf
root@localhost:~#
root@localhost:~# mdadm --examine --scan --verbose
root@localhost:~#
root@localhost:~# mdadm -Cv /dev/md0 -n11 -l5 -c128 /dev/sd[b-l] -x1
/dev/sdm -R -f --verbose
mdadm: layout defaults to left-symmetric
mdadm: size set to 976762496K
mdadm: array /dev/md0 started.
root@localhost:~#
root@localhost:~# cat /proc/mdstat
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5]
[raid4] [raid10]
md0 : active raid5 sdm[11](S) sdl[10] sdk[9] sdj[8] sdi[7] sdh[6]
sdg[5] sdf[4] sde[3] sdd[2] sdc[1] sdb[0]
9767624960 blocks level 5, 128k chunk, algorithm 2 [11/11]
[UUUUUUUUUUU]
[>....................] resync = 0.0% (265128/976762496)
finish=306.8min speed=53025K/sec
unused devices: <none>
root@localhost:~#
root@localhost:~# cat /etc/mdadm.conf
root@localhost:~#
root@localhost:~# mdadm --examine --scan --verbose
ARRAY /dev/md0 level=raid5 num-devices=11
UUID=09db8873:25545721:e5d66b81:63573add
spares=1
devices=/dev/sdm,/dev/sdl,/dev/sdk,/dev/sdj,/dev/sdi,/dev/sdh,/dev/sdg,/d
ev/sdf,/dev/sde,/dev/sdd,/dev/sdc,/dev/sdb
root@localhost:~#
root@localhost:~# mdadm -D /dev/md0
/dev/md0:
Version : 00.90
Creation Time : Fri Aug 29 05:34:40 2008
Raid Level : raid5
Array Size : 9767624960 (9315.13 GiB 10002.05 GB)
Used Dev Size : 976762496 (931.51 GiB 1000.20 GB)
Raid Devices : 11
Total Devices : 12
Preferred Minor : 0
Persistence : Superblock is persistent
Update Time : Fri Aug 29 05:34:41 2008
State : active, resyncing
Active Devices : 11
Working Devices : 12
Failed Devices : 0
Spare Devices : 1
Layout : left-symmetric
Chunk Size : 128K
Rebuild Status : 0% complete
UUID : 09db8873:25545721:e5d66b81:63573add
Events : 0.3
Number Major Minor RaidDevice State
0 8 16 0 active sync /dev/sdb
1 8 32 1 active sync /dev/sdc
2 8 48 2 active sync /dev/sdd
3 8 64 3 active sync /dev/sde
4 8 80 4 active sync /dev/sdf
5 8 96 5 active sync /dev/sdg
6 8 112 6 active sync /dev/sdh
7 8 128 7 active sync /dev/sdi
8 8 144 8 active sync /dev/sdj
9 8 160 9 active sync /dev/sdk
10 8 176 10 active sync /dev/sdl
11 8 192 - spare /dev/sdm
root@localhost:~#
root@localhost:~# shutdown -r now
Broadcast message from root@localhost
(/dev/pts/0) at 5:35 ...
The system is going down for reboot NOW!
root@localhost:~# login as: root
root@192.168.1.15's password:
root@localhost:~#
root@localhost:~#
root@localhost:~# cat /proc/mdstat
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5]
[raid4] [raid10]
unused devices: <none>
root@localhost:~#
root@localhost:~# mdadm --examine --scan --verbose
ARRAY /dev/md0 level=raid5 num-devices=11
UUID=09db8873:25545721:e5d66b81:63573add
spares=1
devices=/dev/sdm,/dev/sdl,/dev/sdk,/dev/sdj,/dev/sdi,/dev/sdh,/dev/sdg,/d
ev/sdf,/dev/sde,/dev/sdd,/dev/sdc,/dev/sdb
root@localhost:~#
root@localhost:~# cat /etc/mdadm.conf
root@localhost:~#
root@localhost:~# mdadm --assemble --scan --verbose
mdadm: No arrays found in config file
root@localhost:~#
root@localhost:~# mdadm --scan
mdadm: --scan does not set the mode, and so cannot be the first option.
root@localhost:~# mdadm -E /dev/md0
mdadm: cannot open /dev/md0: No such file or directory
root@localhost:~#
root@localhost:~# mdadm -X /dev/md0
mdadm: failed to find file /dev/md0: No such file or directory
root@localhost:~# mdadm --assemble --scan --verbose /dev/md0
mdadm: /dev/md0 not identified in config file.
root@localhost:~# mdadm --query /dev/md0
mdadm: cannot open /dev/md0: No such file or directory
root@localhost:~#
-----Original Message-----
From: NeilBrown <redacted>
To: thomas62186218@aol.com
Sent: Thu, 28 Aug 2008 5:04 am
Subject: Re: No md superblock immediately after creating RAID 5 /dev/md0
On Thu, August 28, 2008 6:32 pm, thomas62186218@aol.com wrote:
mdadm -Cv /dev/md0 -n12 -l5 -c128 /dev/sd[b-m] -R -f
^^ 12.
root@localhost:~# cat /proc/mdstat Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [ra id10] md0 : active raid5 sdm1[11](S) sdl1[10] sdk1[9] sdj1[8] sdi1[7]
sdh1[6]
sdg1[5] sdf1[4] sde1[3] sdd1[2] sdc1[1] sdb1[0]
4883839360 blocks level 5, 16k chunk, algorithm 2 [11/11]^^ 11!
root@localhost:~# cat /etc/mdadm.conf DEVICE /dev/sd* ARRAY /dev/md0 level=raid5 num-devices=12
^^ 12 ??
Raid Devices : 11
^^ Something odd here.
root@localhost:/var/log# mdadm --assemble --scan mdadm: no devices found for /dev/md0
Could you add --verbose to that line and try again? NeilBrown P.S. Thanks for including lots of details!