Repairing the kernel?

[meta59]

Today I booted up FC 15 and it hung on "start up the nfs file locking service." It boots if I select a different kernel in the grub menu. How do I repair the most recent kernel(the one that boots automatically)? I tried running updates but that didnt fix it.

[stevea]

You can select a different kernel to boot by editing /boot/grub/grub.conf or using the 'grubby' utility.
Either requires privilege.

sudo sed -e s/default=0/default=1/ -i /boot/grub/grub.conf
selects the 'previous' kernel or

sudo grubby --make-default /boot/vmlinuz-2.6......

where you need to find the correct name for the vmlinuz... file you want to boot.

sudo grubby --default-kernel

prints the kernel selected for boot.