[CentOS] question on software raid

Mon Apr 4 08:55:39 UTC 2011
Kay Diederichs <kay.diederichs at uni-konstanz.de>

On 04/01/2011 05:32 PM, Jerry Geis wrote:
> dmesg is not reporting any issues.
> The /proc/mdstat looks fine.
> md0 : active raid1 sdb1[1] sda1[0]
>      X blocks [2/2]  [UU]
> however /var/log/messages says:
> smartd[3392] Device /dev/sda 20 offline uncorrectable sectors
> The machine is running fine.. raid array looks good - what
> is up with smartd?
> THanks,
> Jerry

This means that you will be in trouble sooner or later.

Is there only sda1 on sda? If so, try

mdadm /dev/md0 --fail /dev/sda1
mdadm /dev/md0 --remove /dev/sda1
mdadm /dev/md0 --add /dev/sda1

which will end up overwriting the offline uncorrectable sectors. In most 
cases this fixes the disk. But you will have to monitor it carefully 
from now on.