Re: mdadm -D /dev/md3: 1 0 0 0 sync ???

On Wednesday December 22, ferenc@avz.xs4all.nl wrote:

Hello list,

Does anybody know what this means:

# mdadm -D /dev/md3
<snip>
     Number   Major   Minor   RaidDevice State
        0       3        6        0      active sync   /dev/hda6
        1       0        0        0      sync

        2      22        6        2      active sync   /dev/hdc6

Please help. Which disk is '1  0  0  0  sync'? The array is currently 
degraded. How do I remove number 1 and bring number 2 up?

This is a missing drive, that is marked as in-sync, which is bad.  
I don't know how it happened, but the best way to fix it is to remake
the array:

   umount ....
   mdadm -S /dev/md3
   mdadm -C /dev/md3 -R -l1 -n2 /dev/hda6 missing
   mdadm /dev/md3 -a /dev/hdc6

should make it work.  It won't destroy any data

NeilBrown

quoted

    Number   Major   Minor   RaidDevice State
       0       3        6        0      active sync   /dev/hda6
       1       0        0        0      sync

       2      22        6        2      active sync   /dev/hdc6

Please help. Which disk is '1  0  0  0  sync'? The array is currently 
degraded. How do I remove number 1 and bring number 2 up?

This is a missing drive, that is marked as in-sync, which is bad.  
I don't know how it happened, but the best way to fix it is to remake
the array:

   umount ....
   mdadm -S /dev/md3
   mdadm -C /dev/md3 -R -l1 -n2 /dev/hda6 missing
   mdadm /dev/md3 -a /dev/hdc6

should make it work.  It won't destroy any data

Worked as you said. Thank you very very much!

cheers

Ferenc