Recreate RAID10 after OS disk failure

Today I had to reboot my OMW because of failures on log in the web gui.. but after it failed to reboot hanging just after the grub I understood the disk was damaged.

I had 1 OS hard disk (crashed), and 4 hd in raid 1+0 (coupled 2Tb sda + 1Tb sdb / 2Tb sdc + 1Tb sdd) to obtain 3Tb mirrored.

Now I reinstalled a new OS hard disk, but I don't know how to recognize/recreate the old RAID array.

# blkid

/dev/sda1: UUID="0c0bc765-b7aa-4532-98eb-d4cb83d21b0e" TYPE="ext4"
/dev/sda5: UUID="f163d7c5-e228-4306-9f37-09bceb734ba1" TYPE="swap"
/dev/sde1: UUID="c17401d3-1d95-42d5-acc4-e0e64cdf0927" TYPE="ext4"
/dev/sde5: UUID="0eb849ea-8a2b-4f6d-8618-a9a38cddcc9b" TYPE="swap"

#fdisk -l

Disk /dev/sda: 2000.4 GB, 2000398934016 bytes
255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x0008c37b
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 3890782207 1945390080 83 Linux
/dev/sda2 3890784254 3907028991 8122369 5 Extended
Partition 2 does not start on physical sector boundary.
/dev/sda5 3890784256 3907028991 8122368 82 Linux swap / Solaris

Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 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: 2000.4 GB, 2000398934016 bytes
255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x00000000
Disk /dev/sdc doesn't contain a valid partition table

Disk /dev/sdd: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x00000000
Disk /dev/sdd doesn't contain a valid partition table

OMV boot disk:

Disk /dev/sde: 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: 0x000560d9
Device Boot Start End Blocks Id System
/dev/sde1 * 2048 960526335 480262144 83 Linux
/dev/sde2 960528382 976771071 8121345 5 Extended
/dev/sde5 960528384 976771071 8121344 82 Linux swap / Solaris

So, that's all.. please help!

Hey, I hoped for some ideas/suggestions..

well, the status is still this: new clean install on new OS hard disk (the 500Gb one) and I don't know how to recreate the RAID.

Physical disks are:

I think I could try to re-create the RAID 1+0 directly via GUI but when i go in storage/RAID (that is empty) and I try to add a RAID it offers me only sdc/sdd/sde or sdb/sdd/sde (it changed after a reboot).

Trying to explain me I discovered that in storage/filesystem it shows:

/dev/sda1 ext4 n/c n/c n/c No No Online
/dev/sdb1 ext4 1.78 TiB 1.69 TiB 1.06 GiB yes yes Online

so it seems to mount the boot fs alternatively on sdb1 or sdc1.

frankly I don't know if this is normal..

maybe I could use mdadm to recreate the raid but I don't know the syntax (even because mine is a raid 10 not so common..)

PLEASE HELP!!

well maybe I could reassemble half raid:

mdadm --assemble /dev/md127 /dev/sd[acde] --verbose --force

so I could restart a degraded stripe array, mount the fs, share & copy everything in a safe place and try to rebuild mirror..

wait, wait, not so many post.. too may suggestions..

cat /proc/mdstat

Personalities :
unused devices: <none>

blkid

/dev/sda1: UUID="c17401d3-1d95-42d5-acc4-e0e64cdf0927" TYPE="ext4"
/dev/sda5: UUID="0eb849ea-8a2b-4f6d-8618-a9a38cddcc9b" TYPE="swap"
/dev/sdb1: UUID="0c0bc765-b7aa-4532-98eb-d4cb83d21b0e" TYPE="ext4"
/dev/sdb5: UUID="f163d7c5-e228-4306-9f37-09bceb734ba1" TYPE="swap"

but fdisk -l shows that sda is the boot hard disk, the 500Gb..

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: 0x000560d9

Device Boot Start End Blocks Id System
/dev/sda1 * 2048 960526335 480262144 83 Linux
/dev/sda2 960528382 976771071 8121345 5 Extended
/dev/sda5 960528384 976771071 8121344 82 Linux swap / Solaris

Disk /dev/sdb: 2000.4 GB, 2000398934016 bytes
255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x0008c37b

Device Boot Start End Blocks Id System
/dev/sdb1 * 2048 3890782207 1945390080 83 Linux
/dev/sdb2 3890784254 3907028991 8122369 5 Extended
Partition 2 does not start on physical sector boundary.
/dev/sdb5 3890784256 3907028991 8122368 82 Linux swap / Solaris

Disk /dev/sdc: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 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: 2000.4 GB, 2000398934016 bytes
255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x00000000

Disk /dev/sdd doesn't contain a valid partition table

Disk /dev/sde: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x00000000

Disk /dev/sde doesn't contain a valid partition table

the output is empty

microserver hp proliant ml150, amd64, 4Gb ram

empty

Zitat

lsmod | grep raid
raid10 30812 0
md_mod 87742 1 raid10

So I could try:

Zitat

mdadm --assemble /dev/md127 /dev/sd[bcde] --verbose --force

with no risk to lose all?

mdadm --assemble /dev/md127 /dev/sd[bcde] --verbose --force

Zitat

mdadm: looking for devices for /dev/md127
mdadm: Cannot assemble mbr metadata on /dev/sdb
mdadm: /dev/sdb has no superblock - assembly aborted

cat /proc/mdstat

Zitat

Personalities : [raid10]
unused devices: <none>

i'm afraid i'm sure it is a 10.. coupled in stripe and mirrored.. 2Tb+1Tb mirrored to 2Tb+1Tb.. unless it made "motu proprio" a silent substitution with a raid5..

could I try to assemble a stripe between bc or de, to obtain a degraded mirror?

I don't know the syntax of mdadm, how do you define the raid level, the correct assemble of disks.. ?

the man is not so helpful for a noob

Zitat

cat /proc/mdstat

Personalities : [raid10] [raid1] [raid0]
unused devices: <none>

Ok, now I have 3 personalities, but if I try to assemble the two raid0 arrays:

mdadm --assemble /dev/md127 /dev/sdb /dev/sdc --verbose --force

I have:

Zitat

mdadm: looking for devices for /dev/md127
mdadm: Cannot assemble mbr metadata on /dev/sdb
mdadm: /dev/sdb has no superblock - assembly aborted

and the same kind of result I have with sdd and sde.

maybe I mistake the syntax?