Installation guide

Chapter 4. Boot Loaders 83
4.7.1. Special Configuration File Commands
The following commands can only be used in the GRUB menu configuration file:
• color
normal-color selected-color — Allows for the set up specific colors to be
used in the menu, where two colors are configured as the foreground and background. Use simple
color names, such as red/black. For example:
color red/black green/blue
• default
title-name — The default entry title name that will be loaded if the menu interface
times out.
• fallback
title-name — If used, the entry title name to try if first attempt fails.
• hiddenmenu — If used, prevents the GRUB menu interface from being displayed, loading the
default entry when the timeout period expires. The user can see the standard GRUB menu by
pressing the [Esc] key.
• password
password — If used, prevents the user who does not know the password from
editing the entries for this menu option.
Optionally, it is possible to specify an alternate menu configuration file after the
password , so
that, if the password is known, GRUB will restart the second stage of the boot loader and use this
alternate configuration file to build the menu. If this alternate file is left out of the command, then a
user who knows the password would be able to edit the current configuration file.
• timeout — If used, sets the interval, in seconds, before GRUB loads the entry designated by the
default command.
• splashimage — Specifies the location of the splash screen image to be used when GRUB boots.
• title — Sets a title to be used with a particular group of commands used to load an operating
system.
The # character can be used to place comments in the menu configuration file.
4.7.2. Configuration File Structure
GRUB menu interface’s configuration file is /boot/grub/grub.conf. The commands to set the
global preferences for the menu interface are placed at the top of the file, followed by the different
entries for each of the operating systems or kernels listed in the menu.
A very basic GRUB menu configuration file designed to boot either Red Hat Linux or Microsoft
Windows 2000 might look as follows:
default=0
timeout=10
splashimage=(hd0,0)/grub/splash.xpm.gz
# section to load linux
title Red Hat Linux (2.4.18-5.47)
root (hd0,0)
kernel /vmlinuz-2.4.18-5.47 ro root=/dev/sda2
initrd /initrd-2.4.18-5.47.img
# section to load Windows 2000
title windows
rootnoverify (hd0,0)
chainloader +1