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I'm trying to recover a friends data from a Sony Vaio VGN-AW47GH Laptop. It has a pair of Toshiba MK5055GS 2.5" 500GB HDD combined (according to my reading) into a 1TB RAID0. The laptop is no longer working so I'm trying to bring them up on my Ubuntu 14.04 system.

I need help with the syntax for the /etc/mdadm/mdadm.conf file to make the RAID0 mountable by Ubuntu. Hopefully someone familiar with mdadm.conf is able to point me in the right direction as the man page and searches online aren't making it clear enough for me to tweak.

They are appearing as /dev/sda & /dev/sdb and I get the following from mdadm examine/scan after running mdadm --assemble --scan

# mdadm --examine --scan /dev/sda
mdadm: ARRAY line /dev/md/imsm0 has no identity information.
ARRAY metadata=imsm UUID=99fcd315:2ac78f08:08014b0a:33f4585f
ARRAY /dev/md/Volume0 container=99fcd315:2ac78f08:08014b0a:33f4585f member=0 UUID=245d2401:2ad11a3c:6edacb92:47ce3340

Results examine/scan /dev/sdb

# mdadm --examine --scan /dev/sdb
mdadm: ARRAY line /dev/md/imsm0 has no identity information.
ARRAY metadata=imsm UUID=99fcd315:2ac78f08:08014b0a:33f4585f
ARRAY /dev/md/Volume0 container=99fcd315:2ac78f08:08014b0a:33f4585f member=0 UUID=245d2401:2ad11a3c:6edacb92:47ce3340

Here's the examine results without the --scan option:

# mdadm --examine /dev/sda
mdadm: ARRAY line /dev/md/imsm0 has no identity information.
/dev/sda: 
          Magic : Intel Raid ISM Cfg Sig.
        Version : 1.0.00
    Orig Family : 08b9238d
         Family : 08b9238d
     Generation : 00001c59
     Attributes : All supported
           UUID : 99fcd315:2ac78f08:08014b0a:33f4585f
       Checksum : 1b2c84f0 correct
    MPB Sectors : 1
          Disks : 2
   RAID Devices : 1

  Disk01 Serial : 9934C0KIT
          State : active
             Id : 00040000
    Usable Size : 976768264 (465.76 GiB 500.11 GB)

[Volume0]: 
           UUID : 245d2401:2ad11a3c:6edacb92:47ce3340
     RAID Level : 0
        Members : 2
          Slots : [_U]
    Failed disk : 0
      This Slot : 1
     Array Size : 1953536000 (931.52 GiB 1000.21 GB)
   Per Dev Size : 976768264 (465.76 GiB 500.11 GB)
  Sector Offset : 0
    Num Stripes : 3815500
     Chunk Size : 128 KiB
       Reserved : 0
  Migrate State : idle
      Map State : normal
    Dirty State : clean

  Disk00 Serial : 9934C0KJT
          State : active failed
             Id : 00000000
    Usable Size : 976768264 (465.76 GiB 500.11 GB)[/CODE]

Results of examine on /dev/sdb

# mdadm --examine /dev/sdb
mdadm: ARRAY line /dev/md/imsm0 has no identity information.
/dev/sdb:
          Magic : Intel Raid ISM Cfg Sig.
        Version : 1.0.00
    Orig Family : 08b9238d
         Family : 08b9238d
     Generation : 00001c59
     Attributes : All supported
           UUID : 99fcd315:2ac78f08:08014b0a:33f4585f
       Checksum : 1b2c84f0 correct
    MPB Sectors : 1
          Disks : 2
   RAID Devices : 1

[Volume0]:
           UUID : 245d2401:2ad11a3c:6edacb92:47ce3340
     RAID Level : 0
        Members : 2
          Slots : [_U]
    Failed disk : 0
      This Slot : ?
     Array Size : 1953536000 (931.52 GiB 1000.21 GB)
   Per Dev Size : 976768264 (465.76 GiB 500.11 GB)
  Sector Offset : 0
    Num Stripes : 3815500
     Chunk Size : 128 KiB
       Reserved : 0
  Migrate State : idle
      Map State : normal
    Dirty State : clean

  Disk00 Serial : 9934C0KJT
          State : active failed
             Id : 00000000
    Usable Size : 976766862 (465.76 GiB 500.10 GB)

  Disk01 Serial : 9934C0KIT
          State : active
             Id : 00040000
    Usable Size : 976766862 (465.76 GiB 500.10 GB)

There doesn't appear to be a /dev/md/Volume0 file in dev. There are a few md files now though:

# ls -la /dev/md* | grep md
brw-rw---- 1 root disk 9, 126 May 24 22:05 /dev/md126
brw-rw---- 1 root disk 9, 127 May 25 22:27 /dev/md127
/dev/md:
lrwxrwxrwx  1 root root    8 May 25 22:27 imsm0 -> ../md127

For /dev/md126

# mdadm --examine --scan /dev/md126
mdadm: ARRAY line /dev/md/imsm0 has no identity information.

For /dev/md17

# mdadm --examine --scan /dev/md127
mdadm: ARRAY line /dev/md/imsm0 has no identity information.
ARRAY metadata=imsm UUID=99fcd315:2ac78f08:08014b0a:33f4585f
ARRAY /dev/md/Volume0 container=99fcd315:2ac78f08:08014b0a:33f4585f member=0 UUID=245d2401:2ad11a3c:6edacb92:47ce3340

Extra Diagnostic info as requested:

# mdadm --assemble --scan
mdadm: ARRAY line /dev/md/imsm0 has no identity information.
mdadm: Container /dev/md126 has been assembled with 2 drives

# cat /proc/mdstat
Personalities : [raid10] [raid1] [raid6] [raid5] [raid4] [linear] [multipath] [raid0] 
md126 : inactive sdb[1](S) sda[0](S)
      5605 blocks super external:imsm

unused devices: <none>

# ls -la /dev/md*
brw-rw---- 1 root disk 9, 126 Jun  8 19:46 /dev/md126

# mount -o ro /dev/md126 /mnt
mount: /dev/md126: can't read superblock

# mdadm --stop /dev/md126
mdadm: stopped /dev/md126

# mdadm --assemble /dev/md0 --verbose --force /dev/sd[ab]
mdadm: looking for devices for /dev/md0
mdadm: /dev/sda is identified as a member of /dev/md0, slot -1.
mdadm: /dev/sdb is identified as a member of /dev/md0, slot -1.
mdadm: Marking array /dev/md0 as 'clean'
mdadm: added /dev/sdb to /dev/md0 as -1
mdadm: added /dev/sda to /dev/md0 as -1
mdadm: Container /dev/md0 has been assembled with 2 drives

# cat /proc/mdstat
Personalities : [raid10] [raid1] [raid6] [raid5] [raid4] [linear] [multipath] [raid0] 
md0 : inactive sda[1](S) sdb[0](S)
      5605 blocks super external:imsm

unused devices: <none>

# mdadm --readonly /dev/md0

# mount -o ro /dev/md0 /mnt
mount: /dev/md0: can't read superblock

Update 12/06/2016

A reboot has reshuffled the devices from sda & sdb to sdg & sdi sorry. I didn't have any luck trying the -I option until I stopped everything and ran it as follows. I've also included the IMSM_NO_PLATFORM environment setting which I forgot I'd put in place by default on reboot.

# export IMSM_NO_PLATFORM=1         # Allow mdadm to access/modify an IMSM array

# mdadm --stop /dev/md0

# mdadm -I /dev/sdg --verbose
mdadm: container /dev/md/imsm0 now has 1 device
mdadm: not enough devices to start the container

# mdadm -I /dev/sdi --verbose
mdadm: container /dev/md/imsm0 now has 2 devices
mdadm: not enough devices to start the container

# mdadm --query --detail /dev/md/imsm0
/dev/md/imsm0:
        Version : imsm
     Raid Level : container
  Total Devices : 2
Working Devices : 2
           UUID : 99fcd315:2ac78f08:08014b0a:33f4585f
  Member Arrays :
    Number   Major   Minor   RaidDevice
       0       8       96        -        /dev/sdg
       1       8      128        -        /dev/sdi

# mdadm --query /dev/md/imsm0
/dev/md/imsm0: 0.00KiB (null) 0 devices, 2 spares. Use mdadm --detail for more detail.

# mdadm -I /dev/md/imsm0 --verbose
mdadm: not enough devices to start the container

# mdadm --assemble --scan
mdadm: array /dev/md/Volume0_0 now has 1 device
mdadm: No arrays found in config file or automatically

# ls -la /dev/md*
brw-rw---- 1 root disk 9, 126 Jun 12 17:02 /dev/md126
brw-rw---- 1 root disk 9, 127 Jun 12 17:00 /dev/md127
/dev/md:
total 0
drwxr-xr-x  2 root root   60 Jun 12 17:00 .
drwxr-xr-x 18 root root 5000 Jun 12 17:02 ..
lrwxrwxrwx  1 root root    8 Jun 12 17:00 imsm0 -> ../md127

# mdadm --query --detail  /dev/md126
/dev/md126:
      Container : /dev/md/imsm0, member 0
     Raid Level : raid0
   Raid Devices : 2
  Total Devices : 1
          State : active, FAILED, Not Started 
 Active Devices : 1
Working Devices : 1
 Failed Devices : 0
  Spare Devices : 0
     Chunk Size : 128K
           UUID : 245d2401:2ad11a3c:6edacb92:47ce3340
    Number   Major   Minor   RaidDevice State
       0       0        0        0      removed
       0       8       96        1      active sync   /dev/sdg

So it looks like I've accessed the imsm0 container which has a missing (removed) device and an ok /dev/sdg device. Any thoughts on how to identify the missing device and re-add it?

Any and all (constructive) input greatly appreciated!

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  • what does cat /proc/mdstat say? please edit and add info to your question, not in a comment. have you tried a mount -o ro (readonly mount) with either /dev/md126 or /dev/md127? – cas Jun 7 '16 at 1:29
  • I would guess that you've created two degraded raid0 arrays, md126 and md127. try stopping both of them (mdadm --stop /dev/md126; mdadm --stop /dev/md127) and then re-assembling them with mdadm --assemble /dev/md0 --verbose --force /dev/sd[ab]. and it's probably best to make sure it stays read-only with mdadm --readonly /dev/md0. – cas Jun 7 '16 at 1:41
  • I don't have any experience with these horrible fakeraids (I didn't think anybody would actually use these...), but /dev/sda is saying active failed, and /dev/sdb is saying This Slot : ?. Sounds like @cas is correct, I think that's why mdadm fails to assemble the array. The mdadm.conf shouldn't have anything to do with this issue (it's mainly for assembling arrays during booting), you should be able to manually assemble the array with mdadm. – Martin von Wittich Jun 8 '16 at 11:04
  • You could try to examine the disks with smartctl, e.g. smartctl -a /dev/sda. Maybe one of them is damaged? – Martin von Wittich Jun 8 '16 at 11:06
  • @MartinvonWittich fakeraid? I assumed the raid-0 was created with mdadm...are you saying that these weren't mdadm raid-0 to begin with? If so, drax has no hope of recovering data from them with mdadm. He'll need a motherboard (or SATA controller) with the same kind of fakeraid as in the Sony Vaio. – cas Jun 8 '16 at 11:10

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