Raid 5 mdadm Problem - Help Please
- by user66260
My Raid 5 array (4 1tb Disks WD10EARS) had was showing as degraded.
I looked and one of the disks wasnt installed, so i re-added it with the mdadm add command.
the array is now showing as (null)Array , but cant be mounted
if i run:
root@warren-P5K-E:/home/warren# sudo mdadm --misc --detail /dev/md0
I get:
mdadm: cannot open /dev/md0: No such file or directory
and running:
root@warren-P5K-E:/home/warren# cat /proc/mdstat
gives me:
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
unused devices: < none >
The data is very important
root@warren-P5K-E:/home/warren# mdadm --examine /dev/sda
/dev/sda:
Magic : a92b4efc
Version : 0.90.00
UUID : 00000000:00000000:00000000:00000000
Creation Time : Sat May 26 12:08:14 2012
Raid Level : -unknown-
Raid Devices : 0
Total Devices : 4
Preferred Minor : 0
Update Time : Sat May 26 12:08:40 2012
State : active
Active Devices : 0
Working Devices : 4
Failed Devices : 0
Spare Devices : 4
Checksum : 82d5b792 - correct
Events : 1
Number Major Minor RaidDevice State
this 1 8 0 1 spare /dev/sda
0 0 8 16 0 spare /dev/sdb
1 1 8 0 1 spare /dev/sda
2 2 8 32 2 spare /dev/sdc
3 3 8 48 3 spare /dev/sdd
root@warren-P5K-E:/home/warren# mdadm --examine /dev/sdb
/dev/sdb:
Magic : a92b4efc
Version : 0.90.00
UUID : 00000000:00000000:00000000:00000000
Creation Time : Sat May 26 12:08:14 2012
Raid Level : -unknown-
Raid Devices : 0
Total Devices : 4
Preferred Minor : 0
Update Time : Sat May 26 12:08:40 2012
State : active
Active Devices : 0
Working Devices : 4
Failed Devices : 0
Spare Devices : 4
Checksum : 82d5b7a0 - correct
Events : 1
Number Major Minor RaidDevice State
this 0 8 16 0 spare /dev/sdb
0 0 8 16 0 spare /dev/sdb
1 1 8 0 1 spare /dev/sda
2 2 8 32 2 spare /dev/sdc
3 3 8 48 3 spare /dev/sdd
root@warren-P5K-E:/home/warren#
oot@warren-P5K-E:/home/warren# mdadm --examine /dev/sdc
/dev/sdc:
Magic : a92b4efc
Version : 0.90.00
UUID : 00000000:00000000:00000000:00000000
Creation Time : Sat May 26 12:08:14 2012
Raid Level : -unknown-
Raid Devices : 0
Total Devices : 4
Preferred Minor : 0
Update Time : Sat May 26 12:08:40 2012
State : active
Active Devices : 0
Working Devices : 4
Failed Devices : 0
Spare Devices : 4
Checksum : 82d5b7b4 - correct
Events : 1
Number Major Minor RaidDevice State
this 2 8 32 2 spare /dev/sdc
0 0 8 16 0 spare /dev/sdb
1 1 8 0 1 spare /dev/sda
2 2 8 32 2 spare /dev/sdc
3 3 8 48 3 spare /dev/sdd
root@warren-P5K-E:/home/warren# mdadm --examine /dev/sdd
/dev/sdd:
Magic : a92b4efc
Version : 0.90.00
UUID : 00000000:00000000:00000000:00000000
Creation Time : Sat May 26 12:08:14 2012
Raid Level : -unknown-
Raid Devices : 0
Total Devices : 4
Preferred Minor : 0
Update Time : Sat May 26 12:08:40 2012
State : active
Active Devices : 0
Working Devices : 4
Failed Devices : 0
Spare Devices : 4
Checksum : 82d5b7c6 - correct
Events : 1
Number Major Minor RaidDevice State
this 3 8 48 3 spare /dev/sdd
0 0 8 16 0 spare /dev/sdb
1 1 8 0 1 spare /dev/sda
2 2 8 32 2 spare /dev/sdc
3 3 8 48 3 spare /dev/sdd
That on the 4 drives.