Linux Kernel in a Nutshell

Modifying the Bootloader For the New Kernel

There are two common Linux kernel bootloaders: GRUB and LILO. GRUB is the one more commonly used in modern distributions, and does some things a little more easily than LILO, but LILO is still seen as well. We'll cover both in this section.

To determine which bootloader your system uses, look in the /boot/ directory. If there is a grub subdirectory:

$ ls -F /boot | grep grub
grub/

then you are using the GRUB program to boot with. If this directory is not present, look for the presence of the /etc/lilo.conf file:

$ ls /etc/lilo.conf
/etc/lilo.conf

If this is present, you are using the LILO program to boot with.

The steps involved in adding a new kernel to each of these programs are different, so follow only the section that corrisponds to the program you are using.

GRUB

To let GRUB know that a new kernel is present, all you need to do is modify the /boot/grub/menu.lst file. For full details on the structure of this file, and all of the different options available, please see the GRUB info pages:

$ info grub

The easiest way to add a new kernel entry to the /boot/grub/menu.lst file is to copy an existing entry. For example, consider the following menu.lst file from a Gentoo system:

timeout 300
default 0

splashimage=(hd0,0)/grub/splash.xpm.gz

title 2.6.16.11
	root (hd0,0)
	kernel /bzImage-2.6.16.11 root=/dev/sda2 vga=0x0305

title 2.6.16
	root (hd0,0)
	kernel /bzImage-2.6.16 root=/dev/sda2 vga=0x0305

The line starting with the word title defines a new ...