Take the 2-minute tour ×
Ask Ubuntu is a question and answer site for Ubuntu users and developers. It's 100% free, no registration required.

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.

share|improve this question
    
Does the following command return anything? mdadm --detail --scan Also, can you see all the disks:- fdisk -l –  popey May 26 '12 at 13:15
    
fdisk -l gives me all the drive info, but mdadm --detail --scan doesnt give me anything, –  user66260 May 26 '12 at 13:26
    
Does "mdadm --examine /dev/sdb1" (replace for each disk/partition), and paste the output. –  popey May 26 '12 at 13:28
    
the output is to large to fit in coment window –  user66260 May 26 '12 at 13:45
    
Edit your question and add the detail there. –  popey May 26 '12 at 13:45

1 Answer 1

You array status shows all your members as SPARES not MEMBERS. The array kicked that member for a reason, remove it from your system and the try to reassemble the remaining drives. If that doesn't work then post your issue on the mdadm mailing list.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.