Can't access drive - Need raid5/linux help

[imt17]

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root@fvdw-sta-kirkwood:/ # mdadm --zero-superblock /dev/sdc7
root@fvdw-sta-kirkwood:/ # mdadm --add /dev/md0 /dev/sdc7
mdadm: added /dev/sdc7
root@fvdw-sta-kirkwood:/ # cat /proc/mdstat
Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4]
md2 : active raid1 sda9[0] sdb9[2]
      875456 blocks [5/2] [U_U__]
     
md1 : active raid1 sda8[0] sdb8[2]
      843328 blocks [5/2] [U_U__]
     
md3 : active raid1 sde5[4]
      255936 blocks [5/1] [____U]
     
md4 : active raid5 sda2[0] sde2[4] sdc2[2] sdb2[1]
      3898947584 blocks super 1.0 level 5, 512k chunk, algorithm 2 [5/4] [UUU_U]
     
md0 : active raid1 sdc7[2] sdb7[1] sda7[0] sde7[3]
      16000 blocks [5/4] [UUUU_]
     
unused devices: <none>


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root@fvdw-sta-kirkwood:/ # mdadm --detail /dev/md0
/dev/md0:
        Version : 0.90
  Creation Time : Thu Jan  1 00:00:15 1970
     Raid Level : raid1
     Array Size : 16000 (15.63 MiB 16.38 MB)
  Used Dev Size : 16000 (15.63 MiB 16.38 MB)
   Raid Devices : 5
  Total Devices : 4
Preferred Minor : 0
    Persistence : Superblock is persistent

    Update Time : Tue Dec  8 15:53:29 2015
          State : clean, degraded
 Active Devices : 4
Working Devices : 4
 Failed Devices : 0
  Spare Devices : 0

           UUID : da0c61be:48b2e856:4c17d85b:cd614625
         Events : 0.772

    Number   Major   Minor   RaidDevice State
       0       8       39        0      active sync   /dev/sda7
       1       8       23        1      active sync   /dev/sdb7
       2       8        7        2      active sync   /dev/sdc7
       3       8       55        3      active sync   /dev/sde7
       4       0        0        4      removed


[Jocko]

As with raid1 members order is not an issue we can keep sde7 as 4th in a first try.

Now, go to clean md1;

try to re-add these devices sdc8 and sde8

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mdadm --re-add  /dev/md1 /dev/sdc8
mdadm --re-add  /dev/md1 /dev/sde8

if it fails use the same way than previously (delete the superblock and add again the device)

Then post

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mdadm --detail /dev/md1

Do the same sequence with md2 (partitions sdc9 and sde9)

[imt17]

Hmmm, had the same errors at first and deleted the superblocks per the previous commands and did both sdc8 and sde8. But thwen I went to use the add sommand I got errors on both. Here is the one for sde8 and then the --detail. sdc8 is the same error.

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root@fvdw-sta-kirkwood:/ # mdadm --zero-superblock /dev/sde8
root@fvdw-sta-kirkwood:/ # mdadm --re-add  /dev/md1 /dev/sde8
mdadm: --re-add for /dev/sde8 to /dev/md1 is not possible
root@fvdw-sta-kirkwood:/ # mdadm --detail /dev/md1
/dev/md1:
        Version : 0.90
  Creation Time : Thu Jan  1 00:00:35 1970
     Raid Level : raid1
     Array Size : 843328 (823.70 MiB 863.57 MB)
  Used Dev Size : 843328 (823.70 MiB 863.57 MB)
   Raid Devices : 5
  Total Devices : 2
Preferred Minor : 1
    Persistence : Superblock is persistent

    Update Time : Wed Dec  2 08:26:10 2015
          State : clean, degraded
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0

           UUID : 7f16912a:3fca4e8e:3d186b3c:53958f34
         Events : 0.244

    Number   Major   Minor   RaidDevice State
       0       8       40        0      active sync   /dev/sda8
       1       0        0        1      removed
       2       8       24        2      active sync   /dev/sdb8
       3       0        0        3      removed
       4       0        0        4      removed


[Jocko]

:disapprove if you delete the superblock you can no longer use the method "--re-add". In this case use the method "--add" as if it is a new member.

[imt17]

Got it

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root@fvdw-sta-kirkwood:/ # mdadm --detail /dev/md1
/dev/md1:
        Version : 0.90
  Creation Time : Thu Jan  1 00:00:35 1970
     Raid Level : raid1
     Array Size : 843328 (823.70 MiB 863.57 MB)
  Used Dev Size : 843328 (823.70 MiB 863.57 MB)
   Raid Devices : 5
  Total Devices : 4
Preferred Minor : 1
    Persistence : Superblock is persistent

    Update Time : Tue Dec  8 16:28:30 2015
          State : clean, degraded
 Active Devices : 4
Working Devices : 4
 Failed Devices : 0
  Spare Devices : 0

           UUID : 7f16912a:3fca4e8e:3d186b3c:53958f34
         Events : 0.282

    Number   Major   Minor   RaidDevice State
       0       8       40        0      active sync   /dev/sda8
       1       8        8        1      active sync   /dev/sdc8
       2       8       24        2      active sync   /dev/sdb8
       3       8       56        3      active sync   /dev/sde8
       4       0        0        4      removed


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root@fvdw-sta-kirkwood:/ # mdadm --detail /dev/md2
/dev/md2:
        Version : 0.90
  Creation Time : Thu Jan  1 00:00:36 1970
     Raid Level : raid1
     Array Size : 875456 (855.08 MiB 896.47 MB)
  Used Dev Size : 875456 (855.08 MiB 896.47 MB)
   Raid Devices : 5
  Total Devices : 4
Preferred Minor : 2
    Persistence : Superblock is persistent

    Update Time : Tue Dec  8 16:31:22 2015
          State : clean, degraded
 Active Devices : 4
Working Devices : 4
 Failed Devices : 0
  Spare Devices : 0

           UUID : 6931896d:781a3429:3d186b3c:53958f34
         Events : 0.3192578

    Number   Major   Minor   RaidDevice State
       0       8       41        0      active sync   /dev/sda9
       1       8        9        1      active sync   /dev/sdc9
       2       8       25        2      active sync   /dev/sdb9
       3       8       57        3      active sync   /dev/sde9
       4       0        0        4      removed


[Jocko]

Now try to get the raid md3 (swap device), by adding sd[abc]5

Post the detail of md3

Then stop all raid

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mdadm --stop /dev/md[01234]

(I assume that md4 is no longer mounted)

and try to reassemble them to see if you get again all the raid devices by using the generic command

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mdadm --assemble

then post

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mdadm --detail /dev/md[01234]

[imt17]

[quote="Jocko"]Now try to get the raid md3 (swap device), by adding sd[abc]5

Post the detail of md3

I am confused on the command for adding sd[abc]5

[imt17]

Is it the same thing we just did but then adding sd1 then adb then sdc? Just making sure.

[imt17]

Did it

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root@fvdw-sta-kirkwood:/ # mdadm --detail /dev/md3
/dev/md3:
        Version : 0.90
  Creation Time : Thu Jan  1 00:00:37 1970
     Raid Level : raid1
     Array Size : 255936 (249.98 MiB 262.08 MB)
  Used Dev Size : 255936 (249.98 MiB 262.08 MB)
   Raid Devices : 5
  Total Devices : 4
Preferred Minor : 3
    Persistence : Superblock is persistent

    Update Time : Tue Dec  8 16:58:08 2015
          State : clean, degraded
 Active Devices : 4
Working Devices : 4
 Failed Devices : 0
  Spare Devices : 0

           UUID : b2ab486e:87e9a97c:3d186b3c:53958f34
         Events : 0.237

    Number   Major   Minor   RaidDevice State
       0       8       37        0      active sync   /dev/sda5
       1       8       21        1      active sync   /dev/sdb5
       2       8        5        2      active sync   /dev/sdc5
       3       0        0        3      removed
       4       8       53        4      active sync   /dev/sde5


[Jocko]

for md3, try to re-add first sda5; sdb5 and sdc5

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mdadm --re-add  /dev/md3 /dev/sda5
mdadm --re-add  /dev/md3 /dev/sdb5
mdadm --re-add  /dev/md3 /dev/sdc5

if one device fails, delete its superblock and use the add method

--So now try to stop the raids and re-assemble them--