[K12OSN] RAID1 failure: need help

[Timothy Legge]

Hi

Basically you need to add the drive/partitions back to each raid set.  I 
had to do this a few weeks ago (thankfully bash history kept the commands):

First off ensure that you know which physical device goes with which 
raid set (I spent a bunch of time going back and forth between the disk 
layout in the hardware browser and the command line).  However, I see 
now that the cat of /proc/mdstat shows that information.  I am not sure 
whether it did for me or not.

When you are sure, you run commands like the following for each 
partition and raid set to add in the missing partition:

mdadm --manage /dev/md1 --add /dev/sda2
mdadm --manage /dev/md2 --add /dev/sda3
mdadm --manage /dev/md3 --add /dev/sda4
mdadm --manage /dev/md0 --add /dev/sda1

They are run one at a time if partitions in multiple raid sets share the 
same physical device.  I did it on my home machine and saw no real issue 
with performance but your results my vary.

The commands above look like they will work given the details you 
provided but I take no responsibility for whatever happens if you assume 
I know what I am talking about (or that I can type). ;-)

Regards and good luck

Tim


Robert Arkiletian wrote:
> Wondering what I should do first. Any advice? Never been in this
> situation before. System is still working fine on 1 drive. BTW
> md0 is /
> md1 is /home
> md2 is /var
> md3 is swap
> 
> [ark at server ~]$ cat /proc/mdstat
> Personalities : [raid1]
> md1 : active raid1 sdb2[2](F) sda2[0]
>      20482752 blocks [2/1] [U_]
> 
> md2 : active raid1 sdb3[1] sda3[0]
>      2048192 blocks [2/2] [UU]
> 
> md3 : active raid1 sdb4[1] sda4[0]
>      1020032 blocks [2/2] [UU]
> 
> md0 : active raid1 sdb1[2](F) sda1[0]
>      12289600 blocks [2/1] [U_]
> 
> Here is where it puked in /var/log/messages
> 
> Sep 30 08:48:03 server kernel: (scsi1:A:1): 160.000MB/s transfers
> (80.000MHz DT, 16bit)
> Sep 30 08:48:03 server kernel: SCSI error : <1 0 1 0> return code = 0x50000
> Sep 30 08:48:03 server kernel: end_request: I/O error, dev sdb, sector 46199
> Sep 30 08:48:03 server kernel: raid1: Disk failure on sdb1, disabling device.
> Sep 30 08:48:03 server kernel:  Operation continuing on 1 devices
> Sep 30 08:48:03 server kernel: SCSI error : <1 0 1 0> return code = 0x50000
> Sep 30 08:48:03 server kernel: end_request: I/O error, dev sdb, sector 50548194
> Sep 30 08:48:03 server kernel: raid1: Disk failure on sdb2, disabling device.
> Sep 30 08:48:03 server kernel:  Operation continuing on 1 devices
> Sep 30 08:48:03 server kernel: RAID1 conf printout:
> Sep 30 08:48:03 server kernel:  --- wd:1 rd:2
> Sep 30 08:48:03 server kernel:  disk 0, wo:0, o:1, dev:sda2
> Sep 30 08:48:03 server kernel:  disk 1, wo:1, o:0, dev:sdb2
> Sep 30 08:48:03 server kernel: RAID1 conf printout:
> Sep 30 08:48:03 server kernel:  --- wd:1 rd:2
> Sep 30 08:48:03 server kernel:  disk 0, wo:0, o:1, dev:sda2
> Sep 30 08:48:03 server kernel: RAID1 conf printout:
> Sep 30 08:48:03 server kernel:  --- wd:1 rd:2
> Sep 30 08:48:03 server kernel:  disk 0, wo:0, o:1, dev:sda1
> Sep 30 08:48:03 server kernel:  disk 1, wo:1, o:0, dev:sdb1
> Sep 30 08:48:03 server kernel: RAID1 conf printout:
> Sep 30 08:48:03 server kernel:  --- wd:1 rd:2
> Sep 30 08:48:03 server kernel:  disk 0, wo:0, o:1, dev:sda1
> 
> 
> 
> --
> Robert Arkiletian
> C++ GUI tutorial http://fltk.org/links.php?V19
> 
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