Find the answer to your Linux question:
Results 1 to 2 of 2
Enjoy an ad free experience by logging in. Not a member yet? Register.
  1. #1

    mdadm Raid 6 Issues


    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;

    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:

    $ 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;

    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;

    sudo mdadm --detail /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.
    Last edited by TaZMAniac; 03-23-2014 at 09:31 PM. Reason: Added Info

  2. #2
    I'm going to mark this as solved.
    I ran sudo fsck /dev/md0
    Found some corruptions and inode errors on the array.
    It fixed what it could but says there are still corruption errors on the drives.

    I plan on backing up the array and then finding which drives have the problems.
    I almost have a hunch that the problem lies in the Sata bus.
    I say this because I had to replace a hard drive due to the same errors.
    The mobo is several years old and has been used hard.

    Peace out.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts