mdadm Raid 6 Issues

Hi,

It's been a long time since i needed any help with Linux but now I'm at the point of tearing my hair out.

I'm using Mint 13 with Mate desktop.

I've been running a mdadm Raid 6 system for quite some time.

It consists of 4 hard drives consisting of 2TB's each.

Yesterday I went to access my Raid 6 at md0 using the icon found in the Computer folder.

The icon was not present.

When i opened Disk Utility and checked the Raid 6 entry it showed it was up and running.

All drives show no errors and they are in the proper configuration.

I decided to stop mdadm and do a repair/resync.

That is when i noticed that when I stopped mdadm the icon I usually click on appeared in the Computer folder.

Today the repair/resync finished but I am still unable to access it.

I tried numerous commands to check the array and disks and nothing appears to be wrong.

My Raid 6 uses the following drives;

sde, sdf, sdg, sdi

If I try to mount md0 from the terminal using mount /dev/md0 I get an error that md0 is not found in fstab.

So I added an entry in fstab to mount it on boot.

It did not mount and generated no error messages.

I checked the kernel logs and they all have the same entries for the past week.

In fact i have another hard drive that has Mint on it and also ran my Raid 6. I replaced it about 3 months ago with a new drive because it was failing.

The kernel logs on that drive have the same entries for mdadm and md0 that my new drive has.

Here is a copy of today's kernel logs;

Code:

ar 23 10:11:20 DaLinux kernel: [ 5.551901] md: bind<sdf>

Mar 23 10:11:20 DaLinux kernel: [ 5.569025] md: bind<sde>

Mar 23 10:11:20 DaLinux kernel: [ 5.572212] md: bind<sdi>

Mar 23 10:11:20 DaLinux kernel: [ 5.601595] md: bind<sdg>

Mar 23 10:11:20 DaLinux kernel: [ 5.629825] bio: create slab <bio-1> at 1

Mar 23 10:11:20 DaLinux kernel: [ 5.629840] md/raid:md0: device sdg operational as raid disk 2

Mar 23 10:11:20 DaLinux kernel: [ 5.629842] md/raid:md0: device sdi operational as raid disk 3

Mar 23 10:11:20 DaLinux kernel: [ 5.629844] md/raid:md0: device sde operational as raid disk 0

Mar 23 10:11:20 DaLinux kernel: [ 5.629845] md/raid:md0: device sdf operational as raid disk 1

Mar 23 10:11:20 DaLinux kernel: [ 5.630175] md/raid:md0: allocated 4280kB

Mar 23 10:11:20 DaLinux kernel: [ 5.630222] md/raid:md0: raid level 6 active with 4 out of 4 devices, algorithm 2

Mar 23 10:11:20 DaLinux kernel: [ 5.630224] RAID conf printout:

Mar 23 10:11:20 DaLinux kernel: [ 5.630225] --- level:6 rd:4 wd:4

Mar 23 10:11:20 DaLinux kernel: [ 5.630226] disk 0, o:1, dev:sde

Mar 23 10:11:20 DaLinux kernel: [ 5.630227] disk 1, o:1, dev:sdf

Mar 23 10:11:20 DaLinux kernel: [ 5.630228] disk 2, o:1, dev:sdg

Mar 23 10:11:20 DaLinux kernel: [ 5.630229] disk 3, o:1, dev:sdi

Mar 23 10:11:20 DaLinux kernel: [ 5.630250] md0: detected capacity change from 0 to 4000528203776

Here is is the output of cat /proc/mdstat:

Code:

$ cat /proc/mdstat

Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]

md0 : active raid6 sde[0] sdi[3] sdg[2] sdf[1]

3906765824 blocks super 1.2 level 6, 512k chunk, algorithm 2 [4/4] [uUUU]

unused devices: <none>

I tried the following command and here is the output;

Code:

sudo mdadm --assemble --force /dev/md0 /dev/sd[efgi]

mdadm: /dev/md0 has been started with 4 drives.

I also ran this command and it shows that md0 is clean;

Code:

sudo mdadm --detail /dev/md0

/dev/md0:

Version : 1.2

Creation Time : Mon Jan 21 21:21:18 2013

Raid Level : raid6

Array Size : 3906765824 (3725.78 GiB 4000.53 GB)

Used Dev Size : 1953382912 (1862.89 GiB 2000.26 GB)

Raid Devices : 4

Total Devices : 4

Persistence : Superblock is persistent

Update Time : Sun Mar 23 16:10:38 2014

State : clean

Active Devices : 4

Working Devices : 4

Failed Devices : 0

Spare Devices : 0

Layout : left-symmetric

Chunk Size : 512K

Name : DaNixBox:0

UUID : 320fd47e:235e2eee:675ae146:6bb49a2e

Events : 46

Number Major Minor RaidDevice State

0 8 64 0 active sync /dev/sde

1 8 80 1 active sync /dev/sdf

2 8 96 2 active sync /dev/sdg

3 8 128 3 active sync /dev/sdi

Any help would be appreciated.

Thanks!

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