Recently my raspberry Pi power was disconnected without warning. When it powered back on, it rebooted in 'emergency mode'. After going through the steps to comment out the extra drive within the /etc/fstab file, I was able to boot up the Pi but my OMV RAID 1 would not mount. When tried to mount I was prompted with an error message. After browsing the Internet I ran fsck on the /dev/md0 mount and it completed successfully. My RAID 1 array was now able to be mounted but I could not see any of my data. The drive space of the array was also correctly reporting so I know there is data on the array. I was hoping you can help me with walking me through how to make my data browsable again. After fixing this, I plan on copying the data to a separate drive not using the RAID setup anymore. I will use Rsync instead.
Here is my output from the commands:
pi@raspberrypi:~ $ sudo cat /proc/mdstat
Personalities : [raid1]
md0 : active raid1 sdb1[0]
3906885440 blocks super 1.2 [2/1] [U_]
bitmap: 0/30 pages [0KB], 65536KB chunk
unused devices: <none>
pi@raspberrypi:~ $ sudo blkid
/dev/mmcblk0p1: LABEL_FATBOOT="boot" LABEL="boot" UUID="4BBD-D3E7" TYPE="vfat" PARTUUID="738a4d67-01"
/dev/mmcblk0p2: LABEL="rootfs" UUID="45e99191-771b-4e12-a526-0779148892cb" TYPE="ext4" PARTUUID="738a4d67-02"
/dev/sda1: UUID="4e020b87-9fc1-db8f-613d-8c256e9f486d" UUID_SUB="6dde817d-aeb2-4cba-818d-0e9cfc4841b6" LABEL="raspberrypi:0" TYPE="linux_raid_member" PARTUUID="a7b373ff-8971-4029-b3fd-987efc076ecb"
/dev/sdb1: UUID="4e020b87-9fc1-db8f-613d-8c256e9f486d" UUID_SUB="15ebe1f2-5611-0d88-3e1e-e014279281ec" LABEL="raspberrypi:0" TYPE="linux_raid_member" PARTUUID="a25a896f-6ba8-be48-8d08-d501dc308228"
/dev/md0: UUID="f7f6036d-aab8-49e7-8f45-2ac1cc870e02" TYPE="ext4"
/dev/mmcblk0: PTUUID="738a4d67" PTTYPE="dos"
pi@raspberrypi:~ $ sudo fdisk -l | grep "Disk "
The backup GPT table is corrupt, but the primary appears OK, so that will be used.
Disk /dev/ram0: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram1: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram2: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram3: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram4: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram5: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram6: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram7: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram8: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram9: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram10: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram11: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram12: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram13: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram14: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/ram15: 4 MiB, 4194304 bytes, 8192 sectors
Disk /dev/mmcblk0: 29.8 GiB, 32010928128 bytes, 62521344 sectors
Disk identifier: 0x738a4d67
The backup GPT table is corrupt, but the primary appears OK, so that will be used.
Disk /dev/sdb: 3.7 TiB, 4000787030016 bytes, 7814037168 sectors
Disk model: nal USB 3.0
Disk identifier: 95273E32-0319-6240-8C0F-0DCAE21C8092
Disk /dev/md0: 3.7 TiB, 4000650690560 bytes, 7813770880 sectors
Disk /dev/sda: 3.7 TiB, 4000787030016 bytes, 7814037168 sectors
Disk model: nal USB 3.0
Disk identifier: 9EF89B64-6007-4015-B522-97DCDA041367
pi@raspberrypi:~ $ sudo cat /etc/mdadm/mdadm.conf
# This file is auto-generated by openmediavault (https://www.openmediavault.org)
# WARNING: Do not edit this file, your changes will get lost.
# mdadm.conf
#
# Please refer to mdadm.conf(5) for information about this file.
#
# by default, scan all partitions (/proc/partitions) for MD superblocks.
# alternatively, specify devices to scan, using wildcards if desired.
# Note, if no DEVICE line is present, then "DEVICE partitions" is assumed.
# To avoid the auto-assembly of RAID devices a pattern that CAN'T match is
# used if no RAID devices are configured.
DEVICE partitions
# auto-create devices with Debian standard permissions
CREATE owner=root group=disk mode=0660 auto=yes
# automatically tag new arrays as belonging to the local system
HOMEHOST <system>
# definitions of existing MD arrays
ARRAY /dev/md0 metadata=1.2 name=raspberrypi:0 UUID=4e020b87:9fc1db8f:613d8c25:6e9f486d
pi@raspberrypi:~ $ sudo mdadm --detail --scan --verbose
ARRAY /dev/md0 level=raid1 num-devices=2 metadata=1.2 name=raspberrypi:0 UUID=4e020b87:9fc1db8f:613d8c25:6e9f486d
devices=/dev/sdb1