[CentOS] Centos 5.5, not booting latest kernel but older one instead

[Robert]

On 08/30/2010 09:24 PM, fred smith informed us:

<snip>another curious thing I just noticed is this: the list of kernels 
available
> at boot time (in the actual grub menu shown at boot) IS NOT THE SAME LIST
> THAT APPEARS IN GRUB.CONF. in the boot-time menu, the kernel it boots is
> the most recent one shown, and there are other older ones that do not
> appear in grub.conf. while in grub.conf there are several newer ones that
> do not appear on the boot-time grub menu.
>
> most strange.
>
> BTW, this is a raid-1 array using linux software raid, with two matching
> drives. Is there possibly some way the two drives could have gotten out
> of sync such that whichever one is the actual boot device has invalid
> info in /boot?
>
> and while thinking along those lines, I see a number of mails in root's
> mailbox from "md" notifying us of a degraded array. these all appear to have
> happened, AFAICT, at system boot, over the last several months.
>
> also, /var/log/messages contains a bunch of stuff like the below, also
> apparently at system boot, and I don't really know what it means, though
>    
<snip>

This is not the magic solution that you quite understandably would 
prefer.  I hope
someone can pinpoint your trouble. UNTIL THEN, I think you would be 'way
ahead to make a full backup (or 2) to an external drive, disconnect that 
baby
and start troubleshooting, confident that you won't lose all your data.

I'll bet that #cat /proc/mdstat looks really scary.  Mine looks like this:
[root at madeleine grub]# cat /proc/mdstat
Personalities : [raid1]
md0 : active raid1 sdb1[1] sda1[0]
       409536 blocks [2/2] [UU]

md2 : active raid1 sdb3[1] sda3[0]
       3903680 blocks [2/2] [UU]

md3 : active raid1 sdb4[1] sda4[0]
       108502912 blocks [2/2] [UU]

md1 : active raid1 sdb2[1] sda2[0]
       375567488 blocks [2/2] [UU]

unused devices: <none>
[root at madeleine grub]#

Other than that, the system boots from /boot/grub/grub.conf and that should
be what you see during the boot process.  The other two, /etc/grub.conf and
/boot/grub/menu.lst are symlinks to the real deal
It might be interesting to have a look at /etc/fstab then issue a mount
command with no arguments to see if anything is mounted on /boot

You might find valuable RAID 1 information at:
http://www.howtoforge.com/how-to-set-up-software-raid1-on-a-running-system-incl-grub-configuration-centos-5.3

HTH