[CentOS] Uniprocessor kernel booted after YUM update
mail-lists at karan.org
Tue Sep 20 22:30:19 UTC 2005
Dr R L Oswald wrote:
> Recently, yum installed an updated kernel 2.4.21-32.0.1.ELsmp; when we
> got around to rebooting, we found that some of the machines were running
> the uniprocessor kernel 2.4.21-32.0.1.EL , showing only a single cpu.
Easy workaround = just yum erase the UP kernel package, that way the
system can only come back with a SMP kernel.
> The grub.conf file had been modified in the usual pushdown manner but
> the default kernel had been set at #2 instead of #0.
Do you have a sample from 'before' the update ? also what version of
mkinitrd do you have installed on these machines ? Was that updated at
the same time as the kernel ? Also, what does /etc/redhat-release say ?
> Here is the grub.conf from an affected server:
> Changing the default back to 0 has no effect, it still boots the
> 2.4.21-32.0.1.EL kernel and not the required SMP one. However, if we use
disable the splashimage, and reboot the machine with default=0, what
kernel version is highlighted as the default ?
> I tried the obvious ploy of removing the last three kernel entries in
> grub.conf & setting default=0 but it still manages to boot the
> 2.4.21-32.0.1.EL UP kernel even though it is no longer in the kernel
> menu list.
Are you sure the grub.conf you are editing is indeed the one that is
being used ? ( should be the /boot/grub/grub.conf file ) What does
'parted <bootdev> print' say ?
> We think we will disable automatic yum kernel updates in future , but
> meanwhile, has anyone any suggestions or experiences to share on this
> apart from a complete re-install of each affected node?
I would suggest you provide some more info, and also try to reinstall
grub. At the very least grub should accomodate changes being made in the
fwiw, I've tried to reproduce this issue here on a CentOS3/i386 SMP
machine  and am unable to do so. The kernel update installs and sets
up grub.conf fine.
 CentOS 3.4 install and yum update from there.
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