a friend of mine had an RAID 0 Array of two 500GB HDDs (Windows - NTFS - Dell preinstalled) and one seems to have an bad sector. So i started the PC from Ubuntu Live Disk (15.04) and tried to assemble the array with mdadm to rescue data (cos from windows it always breaks).
There are 3 Partitions over the Raid:
- first on /dev/sda Windows Boot [100MB]
- second i guess is a Dell Recovery Partition [100GB])
- and the third over /dev/sda and /dev/sdb (around 850GB together, should be an NTFS Partition Windows C:\)
And again everything listed:
$ sudo mdadm --examine /dev/sda
/dev/sda:
Magic : Intel Raid ISM Cfg Sig.
Version : 1.0.00
Orig Family : f3069b3e
Family : f3069b3e
Generation : 00006a1b
Attributes : All supported
UUID : b0ad0525:0ddce192:803168da:22a1ffe4
Checksum : c280a1b0 correct
MPB Sectors : 1
Disks : 2
RAID Devices : 1
[ARRAY0]:
UUID : 69bc365d:4feceb32:e1d6c70a:c5d22a9a
RAID Level : 0
Members : 2
Slots : [__]
Failed disk : 1
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 : 5QM21AYL
State : active failed
Id : 00000000
Usable Size : 976766862 (465.76 GiB 500.10 GB)
Disk01 Serial : 5QM220MP
State : active failed
Id : 00010000
Usable Size : 976766862 (465.76 GiB 500.10 GB)
I'm not this firm with RST and mdadm so i googled and tried:
$ sudo mdadm --assemble /dev/md0 /dev/sda /dev/sdb --force
mdadm: Marking array /dev/md0 as 'clean'
mdadm: Container /dev/md0 has been assembled with 2 drives
and then:
$ sudo mount -t ntfs /dev/md0 /home/olddata/
Failed to read bootsector (size=0)
Failed to sync device /dev/md0: Input/output error
Failed to mount '/dev/md0': Invalid argument
The device '/dev/md0' doesn't seem to have a valid NTFS.
Maybe the wrong device is used? Or the whole disk instead of a
partition (e.g. /dev/sda, not /dev/sda1)? Or the other way around?
Can anyone explain to me what is wrong with my definition and guide me on the right path?
Edit:
additional information:
$ sudo fdisk -l
Disk /dev/loop0: 1 GiB, 1101672448 bytes, 2151704 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/sda: 465,8 GiB, 500107862016 bytes, 976773168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xc8000000
Device Boot Start End Sectors Size Id Type
/dev/sda1 * 2048 206847 204800 100M 7 HPFS/NTFS/exFAT
/dev/sda2 206848 245762047 245555200 117,1G 7 HPFS/NTFS/exFAT
/dev/sda3 245762048 1953531903 1707769856 814,3G 7 HPFS/NTFS/exFAT
Disk /dev/sdb: 465,8 GiB, 500107862016 bytes, 976773168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Edit 2:
@psusi: So if i understood the things you said the assemble command over the devices is the right way to start:
$ sudo mdadm --assemble /dev/md0 /dev/sda /dev/sdb --force
mdadm: Marking array /dev/md0 as 'clean'
mdadm: Container /dev/md0 has been assembled with 2 drives
But where to go from here?
$ cat /proc/mdstat
Personalities : [raid0]
md0 : inactive sda[1](S) sdb[0](S)
6306 blocks super external:imsm
unused devices: <none>
$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 465,8G 0 disk
├─sda1 8:1 0 100M 0 part
├─sda2 8:2 0 117,1G 0 part
└─sda3 8:3 0 348,6G 0 part
sdb 8:16 0 465,8G 0 disk
sr0 11:0 1 1,1G 0 rom /cdrom
loop0 7:0 0 1G 1 loop /rofs