[CentOS] system "stuck" with 2.6.18-128 kernel. how to move to 2.6.18-194.17?

[Les Mikesell]

On 10/6/2010 2:36 PM, Aleksey Tsalolikhin wrote:
> Thank you very much for your replies and suggestions!
>
> Turns out I have a broken RAID.  I checked the failed out
> drive by mounting read-only the /boot partition, and it
> is configured to boot the older kernel version (the one the
> system actually boots).
>
> Like Phil said, the OS is seeing one thing, and GRUB another.
>
>
> Questions:
>
> 1. How do I fix the array?   (How do I put the failed out
> drive back in?  (I hope it is a small failure that the
> software RAID can recover from, like a few bad blocks or
> something.  Otherwise I am willing to replace the drive.)
>
>
>
>      #  mdadm /dev/md0 --add /dev/sda1
>      mdadm: Cannot open /dev/sda1: Device or resource busy
>      #
>
> Maybe it's busy because the system really booted off it?

Do you still have it mounted as you mentioned above?  If so, unmount it. 
  If it shows as 'failed' in /proc/mdstat you would have to use mdadm to 
remove it before adding it back.

-- 
   Les Mikesell
    lesmikesell at gmail.com