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Recover mdadm RAID5

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http://www.linuxquestions.org – Tried to look for similar cases but can't find anything similar. I had a system with 4 disks: OS debian: - /dev/sda RAID: - /dev/sdb - /dev/sdc - /dev/sdd The old system disk crashed, so I installed a new one and retried to resync the array. It took two hours to resync the RAID, but I'm unable to mount it. After reboot I get this: Code: hoster:~# mdadm --assemble  --scan -vv mdadm: looking for devices for further assembly mdadm: no RAID superblock on /dev/sdd mdadm: no RAID superblock on /dev/sdc1 mdadm: no RAID superblock on /dev/sdc mdadm: no RAID superblock on /dev/sdb mdadm: cannot open device /dev/root: Device or resource busy mdadm: no RAID superblock on /dev/sda12 mdadm: no RAID superblock on /dev/sda11 mdadm: no RAID superblock on /dev/sda10 mdadm: no RAID superblock on /dev/sda9 mdadm: no RAID superblock on /dev/sda8 mdadm: no RAID superblock on /dev/sda7 mdadm: no RAID superblock on /dev/sda6 mdadm: cannot open device /dev/sda5: Device or resource busy mdadm: no RAID superblock on /dev/sda3 mdadm: no RAID superblock on /dev/sda2 mdadm: no RAID superblock on /dev/sda1 mdadm: cannot open device /dev/sda: Device or resource busy mdadm: /dev/sdd1 is identified as a member of /dev/md/0_0, slot 0. mdadm: no uptodate device for slot 1 of /dev/md/0_0 mdadm: no uptodate device for slot 2 of /dev/md/0_0 mdadm: added /dev/sdd1 to /dev/md/0_0 as 0 mdadm: /dev/md/0_0 assembled from 1 drive - not enough to start the array. mdadm: looking for devices for further assembly mdadm: no RAID superblock on /dev/sdc1 mdadm: no RAID superblock on /dev/sda12 mdadm: no RAID superblock on /dev/sda11 mdadm: no RAID superblock on /dev/sda10 mdadm: no RAID superblock on /dev/sda9 mdadm: no RAID superblock on /dev/sda8 mdadm: no RAID superblock on /dev/sda7 mdadm: no RAID superblock on /dev/sda6 mdadm: no RAID superblock on /dev/sda3 mdadm: no RAID superblock on /dev/sda2 mdadm: no RAID superblock on /dev/sda1 mdadm: /dev/sdd is identified as a member of /dev/md/imsm0, slot -1. mdadm: /dev/sdc is identified as a member of /dev/md/imsm0, slot -1. mdadm: /dev/sdb is identified as a member of /dev/md/imsm0, slot -1. mdadm: added /dev/sdc to /dev/md/imsm0 as -1 mdadm: added /dev/sdb to /dev/md/imsm0 as -1 mdadm: added /dev/sdd to /dev/md/imsm0 as -1 mdadm: Container /dev/md/imsm0 has been assembled with 3 drives mdadm: looking for devices for further assembly mdadm: cannot open device /dev/sdc1: No such file or directory mdadm: no recogniseable superblock on /dev/sda12 mdadm: no recogniseable superblock on /dev/sda11 mdadm: no recogniseable superblock on /dev/sda10 mdadm: no recogniseable superblock on /dev/sda9 mdadm: no recogniseable superblock on /dev/sda8 mdadm: no recogniseable superblock on /dev/sda7 mdadm: no recogniseable superblock on /dev/sda6 mdadm: no recogniseable superblock on /dev/sda3 mdadm: no recogniseable superblock on /dev/sda2 mdadm: no recogniseable superblock on /dev/sda1 mdadm: looking for devices for further assembly mdadm: cannot open device /dev/sdd: Device or resource busy mdadm: cannot open device /dev/sdc: Device or resource busy mdadm: cannot open device /dev/sdb: Device or resource busy mdadm: cannot open device /dev/root: Device or resource busy mdadm: no recogniseable superblock on /dev/sda12 mdadm: no recogniseable superblock on /dev/sda11 mdadm: no recogniseable superblock on /dev/sda10 mdadm: no recogniseable superblock on /dev/sda9 mdadm: no recogniseable superblock on /dev/sda8 mdadm: no recogniseable superblock on /dev/sda7 mdadm: no recogniseable superblock on /dev/sda6 mdadm: cannot open device /dev/sda5: Device or resource busy mdadm: no recogniseable superblock on /dev/sda3 mdadm: no recogniseable superblock on /dev/sda2 mdadm: no recogniseable superblock on /dev/sda1 mdadm: cannot open device /dev/sda: Device or resource busy mdadm: looking in container /dev/md127 mdadm: found match on member /md127/0 in /dev/md127 mdadm: Started /dev/md/raid5_0 with 3 devices mdadm: looking for devices for further assembly mdadm: looking for devices for further assembly mdadm: no recogniseable superblock on 259:0 mdadm: no recogniseable superblock on /dev/md/raid5_0 mdadm: cannot open device /dev/sdd: Device or resource busy mdadm: cannot open device /dev/sdc: Device or resource busy mdadm: cannot open device /dev/sdb: Device or resource busy mdadm: cannot open device /dev/root: Device or resource busy mdadm: no recogniseable superblock on /dev/sda12 mdadm: no recogniseable superblock on /dev/sda11 mdadm: no recogniseable superblock on /dev/sda10 mdadm: no recogniseable superblock on /dev/sda9 mdadm: no recogniseable superblock on /dev/sda8 mdadm: no recogniseable superblock on /dev/sda7 mdadm: no recogniseable superblock on /dev/sda6 mdadm: cannot open device /dev/sda5: Device or resource busy mdadm: no recogniseable superblock on /dev/sda3 mdadm: no recogniseable superblock on /dev/sda2 mdadm: no recogniseable superblock on /dev/sda1 mdadm: cannot open device /dev/sda: Device or resource busy mdadm: looking in container /dev/md127 mdadm: member /md127/0 in /dev/md127 is already assembled After this is done the md status is like: Code: hoster:~# cat /proc/mdstat Personalities : [raid6] [raid5] [raid4] md126 : active (auto-read-only) raid5 sdd[2] sdc[1] sdb[0]       976768000 blocks super external:/md127/0 level 5, 64k chunk, algorithm 0 [3/3] [UUU] md127 : inactive sdd[2](S) sdb[1](S) sdc[0](S)       6771 blocks super external:imsm unused devices: <none> Any help is welcome. 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