I shut down my NAS last night due to a crazy storm in my area in case we had a power outage. After turning the NAS on this morning it wouldn't boot and the RAID 5 was missing. I was able to rebuild the array but one drive is refusing to reconnect to the array.
Here is the code requested.
Code
root@NAS:~# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md0 : active raid5 sdc[1] sdd[2]
5860270080 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/2] [_UU]
unused devices: <none>
root@NAS:~# blkid
/dev/sda1: UUID="f7394bdd-cf50-47f0-99c1-58780a3d5c86" TYPE="ext4"
/dev/sda5: UUID="82b05653-a32e-44e3-a814-917fbcae3d43" TYPE="swap"
/dev/sdb: UUID="9a74f8dd-30a9-5450-999e-44c3e36af552" UUID_SUB="1c584de1-1ec3-2430-3498-5ee0bbb1fe13" LABEL="NAS:NASvol1" TYPE="linux_raid_member"
/dev/sdc: UUID="9a74f8dd-30a9-5450-999e-44c3e36af552" UUID_SUB="22007f01-db25-482f-048a-9ecb92b0b230" LABEL="NAS:NASvol1" TYPE="linux_raid_member"
/dev/sdd: UUID="9a74f8dd-30a9-5450-999e-44c3e36af552" UUID_SUB="aba0a944-bfd2-23ab-43cb-4863269e6b20" LABEL="NAS:NASvol1" TYPE="linux_raid_member"
/dev/md0: LABEL="NASdisk1" UUID="86a1fe6e-c906-434f-8f04-785c5e3a499a" TYPE="ext4"
root@NAS:~# fdisk -l | grep "Disk "
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/md0 doesn't contain a valid partition table
Disk /dev/sdb: 3000.6 GB, 3000592982016 bytes
Disk identifier: 0x00000000
Disk /dev/sdc: 3000.6 GB, 3000592982016 bytes
Disk identifier: 0x00000000
Disk /dev/sda: 500.1 GB, 500107862016 bytes
Disk identifier: 0x0007c7b6
Disk /dev/sdd: 3000.6 GB, 3000592982016 bytes
Disk identifier: 0x00000000
Disk /dev/md0: 6000.9 GB, 6000916561920 bytes
Disk identifier: 0x00000000
root@NAS:~# cat /etc/mdadm/mdadm.conf
# 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=NAS:NASvol1 UUID=9a74f8dd:30a95450:999e44c3:e36af552
# instruct the monitoring daemon where to send mail alerts
MAILADDR zachlow77@gmail.com
MAILFROM root
root@NAS:~# mdadm --detail --scan --verbose
ARRAY /dev/md0 level=raid5 num-devices=3 metadata=1.2 name=NAS:NASvol1 UUID=9a74f8dd:30a95450:999e44c3:e36af552
devices=/dev/sdc,/dev/sddThanks in advance!