daar staat dit:
I used a different technique...
SCENARIO: My old RAID1 computer had failed, and I had only one of the two disks remaining. I wanted to recover its contents. I put it into an external hard drive enclosure and plugged it into the USB drive. I did
Code:
fdisk -l
and discovered that the USB drive was under /dev/sdc3 (based on what I recognized as its size).
First I tried
Code:
mkdir /mnt/old
mount /dev/sdc3 /mnt/old
but it said mount: unknown filesystem type 'linux_raid_member'. Fair enough. That's because /dev/sdc3 was a RAID partition.
But I knew that on my old computer I'd assembled the raid array out of two RAID partitions on two disks and then formatted the raid array as EXT3. So I tried
Code:
mount -o ro -t ext3 /dev/sdc3 /mnt/old
but it said mount: /dev/hdb1 already mounted or /mnt/fat32/ busy. Fair enough. That's because the MDADM subsystem is in charge of mounting the raid partitions and exposing them as /dev/md partitions.
Finding this thread, I tried
Code:
cat /proc/mdstat
It said md125 : inactive sdc3[1](S) 2104500 blocks super 1.0. So this thread was correct: MDADM had indeed grabbed hold of sdc3; but because sdc3's mirror pair wasn't present, it meant that MDADM hadn't been able to offer it up to me as some /dev/md.
I tried "mdadm --assemble --scan --run" as per this thread, but didn't make headway. In the end I found an easier solution:
Code:
mdadm --stop /dev/md125
mount /dev/sdc3 /mnt/old
It said mdadm: stopped /dev/md125 and then it let me mount it okay.
Conclusion: by stopping MDADM from grabbing ownership of the raid partition, I was able to mount it as its underlying ext3 just fine.
(Incidentally, I was also able to plug the drive into my Windows machine and use "Disk Internals Linux Reader" to read it. I image that the Linux Reader might just be ignoring the RAID aspect, and treating it directly as EXT3).
http://nwlinux.com/diagnosing-a-degraded-ubuntu-raid-1-array/