After rebooting my computer, one of my RAID5 arrays would not
assemble. Only two of the four disks were showing as valid. I tried
to force the issue, but that did not work:
# mdadm --assemble --metadata=1.2 --force /dev/md3 /dev/sdk /dev/sdj
/dev/sdg /dev/sdf
mdadm: /dev/md3 assembled from 2 drives - not enough to start the array.
Then I noticed that /proc/mdstat was indicating that ALL of the drives
where spares:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md3 : inactive sdk[0](S) sdf[1](S) sdg[2](S) sdj[4](S)
7814056960 blocks super 1.2
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
If I examine each drive, they seem to be clean:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# mdadm --examine /dev/sd[kfgj]
/dev/sdf:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x1
Array UUID : a49556f3:94cb1a5b:c8c89193:cf239a80
Name : 3
Creation Time : Tue Aug 18 20:28:47 2009
Raid Level : raid5
Raid Devices : 4
Avail Dev Size : 3907028896 (1863.02 GiB 2000.40 GB)
Array Size : 11721085440 (5589.05 GiB 6001.20 GB)
Used Dev Size : 3907028480 (1863.02 GiB 2000.40 GB)
Data Offset : 272 sectors
Super Offset : 8 sectors
State : clean
Device UUID : d2d0b8f1:e61e13c0:3720381b:b4f85e0d
Internal Bitmap : 8 sectors from superblock
Update Time : Mon Oct 26 14:59:53 2009
Checksum : 4d5badd6 - correct
Events : 99508
Layout : left-symmetric
Chunk Size : 256K
Device Role : spare
Array State : A..A ('A' == active, '.' == missing)
/dev/sdg:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x1
Array UUID : a49556f3:94cb1a5b:c8c89193:cf239a80
Name : 3
Creation Time : Tue Aug 18 20:28:47 2009
Raid Level : raid5
Raid Devices : 4
Avail Dev Size : 3907028896 (1863.02 GiB 2000.40 GB)
Array Size : 11721085440 (5589.05 GiB 6001.20 GB)
Used Dev Size : 3907028480 (1863.02 GiB 2000.40 GB)
Data Offset : 272 sectors
Super Offset : 8 sectors
State : clean
Device UUID : a3933e58:9793d274:88dbe01d:18f99a18
Internal Bitmap : 8 sectors from superblock
Update Time : Mon Oct 26 14:59:53 2009
Checksum : 7693f3bb - correct
Events : 1038178
Layout : left-symmetric
Chunk Size : 256K
Device Role : spare
Array State : A..A ('A' == active, '.' == missing)
/dev/sdj:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x1
Array UUID : a49556f3:94cb1a5b:c8c89193:cf239a80
Name : 3
Creation Time : Tue Aug 18 20:28:47 2009
Raid Level : raid5
Raid Devices : 4
Avail Dev Size : 3907028896 (1863.02 GiB 2000.40 GB)
Array Size : 11721085440 (5589.05 GiB 6001.20 GB)
Used Dev Size : 3907028480 (1863.02 GiB 2000.40 GB)
Data Offset : 272 sectors
Super Offset : 8 sectors
State : clean
Device UUID : 281a89c6:38ab1202:73deb60e:f49feb3e
Internal Bitmap : 8 sectors from superblock
Update Time : Mon Oct 26 14:59:53 2009
Checksum : 89453bae - correct
Events : 1038182
Layout : left-symmetric
Chunk Size : 256K
Device Role : spare
Array State : A..A ('A' == active, '.' == missing)
/dev/sdk:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x1
Array UUID : a49556f3:94cb1a5b:c8c89193:cf239a80
Name : 3
Creation Time : Tue Aug 18 20:28:47 2009
Raid Level : raid5
Raid Devices : 4
Avail Dev Size : 3907028896 (1863.02 GiB 2000.40 GB)
Array Size : 11721085440 (5589.05 GiB 6001.20 GB)
Used Dev Size : 3907028480 (1863.02 GiB 2000.40 GB)
Data Offset : 272 sectors
Super Offset : 8 sectors
State : clean
Device UUID : 4b6b6942:ed50c78c:a6ec918c:bac5d970
Internal Bitmap : 8 sectors from superblock
Update Time : Mon Oct 26 14:59:53 2009
Checksum : 3fa3667c - correct
Events : 1038182
Layout : left-symmetric
Chunk Size : 256K
Device Role : Active device 0
Array State : A..A ('A' == active, '.' == missing)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/dev/sdk does not actually say "Device Role : spare".
I tried to re-add the drives, but that also fails:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# mdadm --re-add /dev/md3 /dev/sdj
mdadm: cannot get array info for /dev/md3
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Is there any way to recover the data?
Thanks,
John
--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
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