Red Hat ENTERPRISE LINUX 3 - FOR X86-ITANIUMTM-AMD64 AND INTEL EXTENDED MEMORY 64 TECHNOLO, Installation Manual

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Appendix A. Upgrading Your Current System 61
Figure A-2. Upgrade Boot Loader Configuration
On the
Boot Loader Configuration Screen
, your options are:
Update boot loader configuration — Choose this option to keep your current boot loader configura-
tion (GRUB or LILO depending on what you have currently installed) and have updates applied.
Skip boot loader updating
— Choose this option if you do not want to make any changes to your
current boot loader configuration. If you are using a third party boot loader, you should not update
your boot loader.
Create new boot loader configuration
— Choose this option if you want to create a new boot loader
for your system. If you currently have LILO and want to switch to GRUB, or if you have been using
boot diskettes to boot your Red Hat Enterprise Linux system and want to use a software boot loader
such as GRUB or LILO, create a new boot loader configuration (refer to Section A.3.1 Creating a
New Boot Loader Configuration for more information).
Once you have made your selection, click
Next
to continue.
A.3.1. Creating a New Boot Loader Configuration
In order to boot the system without a boot diskette, you usually need to install a boot loader. A boot
loader is the first software program that runs when a computer starts. It is responsible for loading and
transferring control to the operating system kernel software. The kernel, in turn, initializes the rest of
the operating system.
The installation program provides two boot loaders for you to choose from, GRUB and LILO.
GRUB (GRand Unified Bootloader), which is installed by default, is a very powerful boot loader.
GRUB can load a variety of free operating systems, as well as proprietary operating systems with
chain-loading (the mechanism for loading unsupported operating systems, such as DOS or Windows,
by loading another boot loader).
LILO (LInux LOader) is a versatile boot loader for Linux. It does not depend on a specific file system,
can boot Linux kernel images from floppy diskettes and hard disks, and can even boot other operating
systems.
If you do not want to install GRUB as your boot loader, click
Change boot loader
. You can then
choose to install LILO or choose not to install a boot loader at all.
If you already have a boot loader that can boot Linux and do not want to overwrite your current boot
loader, choose Do not install a boot loader by clicking on the Change boot loader button.