Degraded RAID array after power failure
We have power outages from time to time. And some outlast our UPS.
Now, our array is no longer mounting.
We have 4 500Mb HDDs
root@NAS01:/# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md127 : inactive sdc[2] sdd[3] sdb[1]
2929894536 blocks super 1.2
unused devices: <none>
root@NAS01:/# mdadm --assemble --scan
mdadm: /dev/md/Rd5_0 assembled from 1 drive - not enough to start the array.
mdadm: No arrays found in config file or automatically
root@NAS01:/# blkid
/dev/sdd: UUID="17a63c34-6ecf-2c24-14ce-49d6850db42f" UUID_SUB="8adc819b-cc47-bb0d-4505-636ede742f8d" LABEL="NAS01:Rd5" TYPE="linux_raid_member"
/dev/sda: UUID="17a63c34-6ecf-2c24-14ce-49d6850db42f" UUID_SUB="5d7ec5f2-beea-b34f-6c3d-8a033aa2819b" LABEL="NAS01:Rd5" TYPE="linux_raid_member"
/dev/sdb: UUID="17a63c34-6ecf-2c24-14ce-49d6850db42f" UUID_SUB="81d3588c-867e-b4b6-2247-5f31ac4d7838" LABEL="NAS01:Rd5" TYPE="linux_raid_member"
/dev/sdc: UUID="17a63c34-6ecf-2c24-14ce-49d6850db42f" UUID_SUB="847df33c-e5b2-b3d0-96f9-8d93bb19109d" LABEL="NAS01:Rd5" TYPE="linux_raid_member"
/dev/sdg1: UUID="6dc3c169-be9a-4677-ad83-5f2eeb8f8d84" TYPE="ext4"
/dev/sdg5: UUID="2fc25249-8ced-4d7b-b9ac-8e7935e880e0" TYPE="swap"
root@NAS01:/# fdisk -l | grep "Disk "
Disk /dev/sda doesn't contain a valid partition table
Disk /dev/sdb doesn't contain a valid partition table
Disk /dev/sdc doesn't contain a valid partition table
Disk /dev/sdd doesn't contain a valid partition table
Disk /dev/sda: 1000.2 GB, 1000204886016 bytes
Disk identifier: 0x00000000
Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes
Disk identifier: 0x00000000
Disk /dev/sdc: 1000.2 GB, 1000204886016 bytes
Disk identifier: 0x00000000
Disk /dev/sdd: 1000.2 GB, 1000204886016 bytes
Disk identifier: 0x00000000
Disk /dev/sdg: 128.0 GB, 128035676160 bytes
Disk identifier: 0x000e98df
root@NAS01:/# mdadm --detail --scan --verbose
mdadm: cannot open /dev/md/Rd5: No such file or directory
root@NAS01:/#
I found a really old FDisk output that had saved. Not really sure if I have changed any hardware since. But the array drives should be the same.
jonherns@NAS01:/$ sudo fdisk -l
Disk /dev/sda: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders, total 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
Disk identifier: 0x00000000
Disk /dev/sda doesn't contain a valid partition table
Disk /dev/sdb: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders, total 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
Disk identifier: 0x00000000
Disk /dev/sdb doesn't contain a valid partition table
Disk /dev/sdc: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders, total 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
Disk identifier: 0x00000000
Disk /dev/sdc doesn't contain a valid partition table
Disk /dev/sdd: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders, total 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
Disk identifier: 0x00000000
Disk /dev/sdd doesn't contain a valid partition table
Disk /dev/sde: 4110 MB, 4110228480 bytes
127 heads, 62 sectors/track, 1019 cylinders, total 8027790 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 identifier: 0x0008cfe5
Device Boot Start End Blocks Id System
/dev/sde1 * 2048 7593983 3795968 83 Linux
/dev/sde2 7596030 8026111 215041 5 Extended
/dev/sde5 7596032 8026111 215040 82 Linux swap / Solaris
jonherns@NAS01:/$