My virtual machine host system is running Debian 8.4. I had to restart the system yesterday and did not yet manage to get my mdadm array up and running again. I can boot up normally, but no array (or error) waits for me.
All raid drives are connected by using a pcie sata extension card.
The drives are all there, but mdadm seems to ignore them. Also, I did not find a single error message that might be related to my problem in either dmesg output or any mdadm command I tried.
I am ready to post dmesg data, but I do not know how to filter irrelevant lines (no mdadm output in there anyway).
Usually, lsblk would list the mdadm partitions and stuff on my drives, but not today.
jejanim@vault:~$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 55.9G 0 disk
sdb 8:16 0 55.9G 0 disk
sdc 8:32 0 447.1G 0 disk
└─sdc1 8:33 0 447G 0 part /mnt/music
sdd 8:48 0 55.9G 0 disk
├─sdd1 8:49 0 487M 0 part /boot/efi
├─sdd2 8:50 0 53.7G 0 part /
└─sdd3 8:51 0 1.7G 0 part [SWAP]
sde 8:64 0 238.5G 0 disk
└─sde1 8:65 0 238.5G 0 part
sdf 8:80 0 59.6G 0 disk
sdg 8:96 0 119.2G 0 disk
└─sdg1 8:97 0 119.2G 0 part
Examining all the drives yields something like this for all of the 4 raid drives:
/dev/sdg1:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : 2e3a29fc:12e40f9c:7b6f57d7:b00b62cc
Name : vault:0 (local to host vault)
Creation Time : Mon Aug 3 19:32:06 2015
Raid Level : raid5
Raid Devices : 4
Avail Dev Size : 250004480 (119.21 GiB 128.00 GB)
Array Size : 175747584 (167.61 GiB 179.97 GB)
Used Dev Size : 117165056 (55.87 GiB 59.99 GB)
Data Offset : 62464 sectors
Super Offset : 8 sectors
Unused Space : before=62376 sectors, after=132839424 sectors
State : clean
Device UUID : b1b45ac6:b0acac1e:fc46cdb5:00ac85d6
Update Time : Thu Apr 7 20:24:20 2016
Bad Block Log : 512 entries available at offset 72 sectors
Checksum : 9a815dbc - correct
Events : 94417
Layout : left-symmetric
Chunk Size : 512K
Device Role : Active device 1
Array State : AAAA ('A' == active, '.' == missing, 'R' == replacing)
Seems okay? Well, attempt to assemble it:
jejanim@vault:~$ sudo mdadm --assemble --uuid=2e3a29fc:12e40f9c:7b6f57d7:b00b62cc --verbose /dev/md0
mdadm: looking for devices for /dev/md0
mdadm is not particularly chatty about that one, and a cat /proc/mdstat reveals:
jejanim@vault:~$ cat /proc/mdstat
Personalities :
unused devices: <none>
Do you have any hint on how to assemble the array again?
