Re: help diagnosing bad disk

[Bill Davidsen <davidsen@tmr.com>]

Jon Sabo wrote:
> So I was trying to copy over some Indiana Jones wav files and it
> wasn't going my way.  I noticed that my software raid device showed:
>
> /dev/md1 on / type ext3 (rw,errors=remount-ro)
>
> Is this saying that it was remounted, read only because it found a
> problem with the md1 meta device?  That's what it looks like it's
> saying but I can still write to /.
>
> mdadm --detail showed:
>
> root@recoil:/home/illsci# mdadm --detail /dev/md0
> /dev/md0:
>         Version : 00.90.03
>   Creation Time : Mon Jul 30 21:47:14 2007
>      Raid Level : raid1
>      Array Size : 1951744 ( 1906.32 MiB 1998.59 MB)
>     Device Size : 1951744 (1906.32 MiB 1998.59 MB)
>    Raid Devices : 2
>   Total Devices : 1
> Preferred Minor : 0
>     Persistence : Superblock is persistent
>
>     Update Time : Wed Dec 19 12:59:56 2007
>           State : clean, degraded
>  Active Devices : 1
> Working Devices : 1
>  Failed Devices : 0
>   Spare Devices : 0
>
>            UUID : 157f716c:0e7aebca:c20741f6
> :bb6099c9
>          Events : 0.28
>
>      Number   Major   Minor   RaidDevice State
>        0       8        1        0      active sync   /dev/sda1
>        1       0        0        1      removed
>
> root@recoil:/home/illsci# mdadm --detail /dev/md1
>  /dev/md1:
>         Version : 00.90.03
>   Creation Time : Mon Jul 30 21:47:47 2007
>      Raid Level : raid1
>      Array Size : 974808064 (929.65 GiB 998.20 GB)
>     Device Size : 974808064 (929.65 GiB 998.20 GB)
>     Raid Devices : 2
>   Total Devices : 1
> Preferred Minor : 1
>     Persistence : Superblock is persistent
>
>     Update Time : Wed Dec 19 13:14:53 2007
>           State : clean, degraded
>  Active Devices : 1
> Working Devices : 1
>  Failed Devices : 0
>   Spare Devices : 0
>
>            UUID : 156a030e:9a6f8eb3:9b0c439e:d718e744
>          Events : 0.1990
>
>     Number   Major   Minor   RaidDevice State
>        0       8        2        0      active sync   /dev/sda2
>        1       0        0        1      removed
>
>
> I have two 1 terabyte sata drives in this box.  From what I was
> reading wouldn't it show an F for the failed drive?  I thought I would
> see that /dev/sdb1 and /dev/sdb2 were failed and it would show an F.
> What is this saying and how do you know that its /dev/sdb and not some
> other drive?  It shows removed and that the state is clean, degraded.
> Is that something you can recover from with out returning this disk
> and putting in a new one to add to the raid1 array?
>   

You can try adding the partitions back to your array, but I suspect 
something bad has happened to your sdb drive, since it's failed out of 
both arrays. You can use dmesg to look for any additional information.

Justin gave you the rest of the info you need to investigate, I'll not 
repeat it. ;-)

-- 
Bill Davidsen <davidsen@tmr.com>
  "Woe unto the statesman who makes war without a reason that will still
  be valid when the war is over..." Otto von Bismark