Hello,
I have a client with a failed raid5 that is in desperate need of the
data that's on the raid. The attached file holds the mdadm -E
superblocks that are hopefully the keys to the puzzle. Linux-raid
folks, if you can give any help here it would be much appreciated.
# mdadm -V
mdadm - v1.7.0 - 11 August 2004
# uname -a
Linux hazel 2.6.13-gentoo-r5 #1 SMP Sat Jan 21 13:24:15 PST 2006 i686 Intel(R)
Pentium(R) 4 CPU 2.40GHz GenuineIntel GNU/Linux
Here's my take:
Logfiles show that last night drive /dev/etherd/e0.4 failed and around
noon today /dev/etherd/e0.0 failed. This jibes with the superblock
dates and info.
My assessment is that since the last known good configuration was
0 <missing>
1 /dev/etherd/e0.0
2 /dev/etherd/e0.2
3 /dev/etherd/e0.3
then we should shoot for this. I couldn't figure out how to get there
using mdadm -A since /dev/etherd/e0.0 isn't in sync with e0.2 or e0.3.
If anyone can suggest a way to get this back using -A, please chime in.
The alternative is to recreate the array with this configuration hoping
the data blocks will all line up properly so the filesystem can be mounted
and data retrieved. It looks like the following command is the right
way to do this, but not being an expert I (and the client) would like
someone else to verify the sanity of this approach.
Will
mdadm -C /dev/md0 -n 4 -l 5 missing /dev/etherd/e0.[023]
do what we want?
Linux-raid folks, please reply-to-all as we're probably all not on
the list.
Thanks for your help,
Sam
/dev/etherd/e0.0:
Magic : a92b4efc
Version : 00.90.00
UUID : 8fe1fe85:eeb90460:c525faab:cdaab792
Creation Time : Mon Jan 3 03:16:48 2005
Raid Level : raid5
Device Size : 195360896 (186.31 GiB 200.05 GB)
Raid Devices : 4
Total Devices : 5
Preferred Minor : 0
Update Time : Fri Apr 21 12:45:07 2006
State : clean
Active Devices : 3
Working Devices : 4
Failed Devices : 1
Spare Devices : 1
Checksum : 4cc955da - correct
Events : 0.3488315
Layout : left-asymmetric
Chunk Size : 32K
Number Major Minor RaidDevice State
this 1 152 0 1 active sync /dev/etherd/e0.0
0 0 0 0 0 removed
1 1 152 0 1 active sync /dev/etherd/e0.0
2 2 152 32 2 active sync /dev/etherd/e0.2
3 3 152 48 3 active sync /dev/etherd/e0.3
4 4 152 16 0 spare /dev/etherd/e0.1
/dev/etherd/e0.2:
Magic : a92b4efc
Version : 00.90.00
UUID : 8fe1fe85:eeb90460:c525faab:cdaab792
Creation Time : Mon Jan 3 03:16:48 2005
Raid Level : raid5
Device Size : 195360896 (186.31 GiB 200.05 GB)
Raid Devices : 4
Total Devices : 5
Preferred Minor : 0
Update Time : Fri Apr 21 14:03:12 2006
State : clean
Active Devices : 2
Working Devices : 3
Failed Devices : 3
Spare Devices : 1
Checksum : 4cc991e9 - correct
Events : 0.3493633
Layout : left-asymmetric
Chunk Size : 32K
Number Major Minor RaidDevice State
this 2 152 32 2 active sync /dev/etherd/e0.2
0 0 0 0 0 removed
1 1 0 0 1 faulty removed
2 2 152 32 2 active sync /dev/etherd/e0.2
3 3 152 48 3 active sync /dev/etherd/e0.3
4 4 152 16 4 spare /dev/etherd/e0.1
/dev/etherd/e0.3:
Magic : a92b4efc
Version : 00.90.00
UUID : 8fe1fe85:eeb90460:c525faab:cdaab792
Creation Time : Mon Jan 3 03:16:48 2005
Raid Level : raid5
Device Size : 195360896 (186.31 GiB 200.05 GB)
Raid Devices : 4
Total Devices : 5
Preferred Minor : 0
Update Time : Fri Apr 21 14:03:12 2006
State : clean
Active Devices : 2
Working Devices : 3
Failed Devices : 3
Spare Devices : 1
Checksum : 4cc991fb - correct
Events : 0.3493633
Layout : left-asymmetric
Chunk Size : 32K
Number Major Minor RaidDevice State
this 3 152 48 3 active sync /dev/etherd/e0.3
0 0 0 0 0 removed
1 1 0 0 1 faulty removed
2 2 152 32 2 active sync /dev/etherd/e0.2
3 3 152 48 3 active sync /dev/etherd/e0.3
4 4 152 16 4 spare /dev/etherd/e0.1
/dev/etherd/e0.4:
Magic : a92b4efc
Version : 00.90.00
UUID : 8fe1fe85:eeb90460:c525faab:cdaab792
Creation Time : Mon Jan 3 03:16:48 2005
Raid Level : raid5
Device Size : 195360896 (186.31 GiB 200.05 GB)
Raid Devices : 4
Total Devices : 5
Preferred Minor : 0
Update Time : Thu Apr 20 21:07:50 2006
State : clean
Active Devices : 4
Working Devices : 5
Failed Devices : 0
Spare Devices : 1
Checksum : 4cc84d59 - correct
Events : 0.3482550
Layout : left-asymmetric
Chunk Size : 32K
Number Major Minor RaidDevice State
this 0 152 64 0 active sync /dev/etherd/e0.4
0 0 152 64 0 active sync /dev/etherd/e0.4
1 1 152 0 1 active sync /dev/etherd/e0.0
2 2 152 32 2 active sync /dev/etherd/e0.2
3 3 152 48 3 active sync /dev/etherd/e0.3
4 4 152 16 4 spare /dev/etherd/e0.1
