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

Tue Aug 31 13:42:55 UTC 2010
fred smith <fredex at fcshome.stoneham.ma.us>

On Mon, Aug 30, 2010 at 10:46:26PM -0500, Robert wrote:
> 
> 
> 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]#

here's mine (indented for readability):

cat /proc/mdstat
	Personalities : [raid1] 
	md0 : active raid1 sdb1[1]
	      104320 blocks [2/1] [_U]
	      
	md1 : active raid1 sdb2[1]
	      312464128 blocks [2/1] [_U]
	      
	unused devices: <none>

> 
> 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

yes, they're all symlinked correctly.

> 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

hmmmm....
I find th is in /etc/fstab:

	/dev/md0   /boot   ext3    defaults   1 2

and this in the output of a bare mount command:

	/dev/md0 on /boot type ext3 (rw)

so those look OK.
> 
> 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

I'll take a look at that link. thanks.

I'll also dig for the HOWTO I used when setting it up. As I look at this I
recall that I had to tweak the scripts that create the initrd. so, if one 
of the updates since has reinstalled that, I may no longer be getting the
desired initird built. sounds ominous...

Thanks for the info!


-- 
---- Fred Smith -- fredex at fcshome.stoneham.ma.us -----------------------------
   "For the word of God is living and active. Sharper than any double-edged 
   sword, it penetrates even to dividing soul and spirit, joints and marrow; 
              it judges the thoughts and attitudes of the heart."  
---------------------------- Hebrews 4:12 (niv) ------------------------------