Topic: Faild Disk and which rebuild command

[steve288]

I thought I had set up a mirrored drive on this server when I set it up some time ago.

However now I look at it and it is a little unclear or at least Im confused.
When I go to the GUI I see this ...

 ┌───── Disk redundancy status as of Tuesday January  8, 2013 12:32:18 ───────┐on
 │ Current disk status:                                                       │
 │                                                                            │
 │ Installed disks: sda sdb                                                   │
 │ Used disks: sdb                                                            │
 │ Free disks: sda

   There is an unused disk drive in your system. Do you want to add it to 
 │ the existing RAID array(s)?                                             

 │ WARNING: ALL DATA ON THE NEW DISK WILL BE DESTROYED!                     │
 │                       < Yes >            < No  >                         

-------------------------------------------------------------


# It does not say the array is broken but that it was never set up, I think? This seems odd to me.

# So next I run  "mdadm --query --detail /dev/md1"

-------------------------------------------------------------
/dev/md1:
        Version : 00.90.01
  Creation Time : Mon Mar 19 07:01:49 2012
     Raid Level : raid1
     Array Size : 104320 (101.89 MiB 106.82 MB)
    Device Size : 104320 (101.89 MiB 106.82 MB)
   Raid Devices : 2
  Total Devices : 1
Preferred Minor : 1
    Persistence : Superblock is persistent

    Update Time : Tue Jan  8 12:21:26 2013
          State : clean, degraded
 Active Devices : 1
Working Devices : 1
 Failed Devices : 0
  Spare Devices : 0

           UUID : 2f77238d:b7c25406:a66815f9:eb7a4e3d
         Events : 0.29478

    Number   Major   Minor   RaidDevice State
       0       0        0        -      removed
       1       8       17        1      active sync   /dev/sdb1

--------------------------------------------------------------

And then mdadm --query --detail /dev/md2


--------------------------------------------------------------

/dev/md2:
        Version : 00.90.01
  Creation Time : Mon Mar 19 07:01:49 2012
     Raid Level : raid1
     Array Size : 244091520 (232.78 GiB 249.95 GB)
    Device Size : 244091520 (232.78 GiB 249.95 GB)
   Raid Devices : 2
  Total Devices : 1
Preferred Minor : 2
    Persistence : Superblock is persistent

    Update Time : Tue Jan  8 12:38:51 2013
          State : active, degraded
 Active Devices : 1
Working Devices : 1
 Failed Devices : 0
  Spare Devices : 0

           UUID : 5bea4887:2e3a60be:27565ca9:f2de8ec0
         Events : 0.9182277

    Number   Major   Minor   RaidDevice State
       0       0        0        -      removed
       1       8       18        1      active sync   /dev/sdb2

-----------------------------------------------------------------

# I can see a drive has been removed. Which I think means it has failed or been taken off line.

# Then I run mdstat

------------------------------------------------------------
[root@camp ~]# cat /proc/mdstat


Personalities : [raid1]
md2 : active raid1 sdb2[1]
      244091520 blocks [2/1] [_U]

md1 : active raid1 sdb1[1]
      104320 blocks [2/1] [_U]


-----------------------

I'm not sure but I think this is telling me that sda is completely off line.

If this data is true.

Should I use the gui to set up a second drive as a mirror as if its never been done before. I asume I will loose no data.

Or should I use a rebuilding command and on this I dont know if I should use,

mdadm --add  /dev/md1 /dev/sdb2
or
mdadm --add  /dev/md2 /dev/hdb2

Or perhaps niether. I think it has to do with the the difference between "clean degraded" and "active degraded" in the command, "mdadm --query --detail /dev/md1" or md2.

Please Advise.

[janet]

steve288

As your server history is vague even to yourself, then it's hard for us to comment re what has or has not happened etc.

When I go to the GUI I see this ...

 ┌───── Disk redundancy status as of Tuesday January  8, 2013 12:32:18 ───────┐on
 │ Current disk status:                                                       │
 │                                                                            │
 │ Installed disks: sda sdb                                                   │
 │ Used disks: sdb                                                            │
 │ Free disks: sda

   There is an unused disk drive in your system. Do you want to add it to 
 │ the existing RAID array(s)?                                             

 │ WARNING: ALL DATA ON THE NEW DISK WILL BE DESTROYED!                     │
 │                       < Yes >            < No  >                         

Just select Yes to allow the system to add & resync the drive.

If you value yout data integrity, you should really check both/all drives IMMEDIATELY
http://wiki.contribs.org/Monitor_Disk_Health
or download UBCD (google it) & run drive manufacturers diagnostic tests

[ReetP]

Hi,

as Mary said, it's hard to know what you did or didn't do.

I presume (but you need to check) that they are identical disks ??

Were both disks in the machine when you installed ?

There are various docs in the wiki if you look (use the mediawiki search box on the home page) :

http://wiki.contribs.org/Raid:Manual_Rebuild
http://wiki.contribs.org/AddExtraHardDisk

You also could try mounting the drives with a rescue cd and see if any partitions were ever created on sdb or if it is empty.

B. Rgds
John

[CharlieBrady]

Were both disks in the machine when you installed ?

My guess is, no. This looks like a system  installed on one disk, with a second added later, but not yet added to mirror. The second disk has become /dev/sda, the first moved from sda to sdb.

[ReetP]

My guess is, no. This looks like a system  installed on one disk, with a second added later, but not yet added to mirror. The second disk has become /dev/sda, the first moved from sda to sdb.

Won't argue with that Be interesting to hear the OPs comments.

B. Rgds
John

[CharlieBrady]

Won't argue with that

But I will. I didn't read carefully enough and missed this:

       0       0        0        -      removed
       1       8       18        1      active sync   /dev/sdb2

-----------------------------------------------------------------

# I can see a drive has been removed. Which I think means it has failed or been taken off line.

I don't know exactly when you'll see 'removed' but it's not what you'll see with a failed drive.

I'd suggest OP runs 'history' and reminds him/herself what commands have been run from the root login. It's likely there's been manual intervention here.

[axessit]

Steve288, you need to tell us if the disks are identical.

Do fdisk -l /dev/sda to list the first disk, then fdisk -l /dev/sdb to list the second and post results.

You may need to manually create the partition tables and add the disk back into your array.