Red Hat ENTERPRISE LINUX 5 - VIRTUAL SERVER ADMINISTRATION, Installation Manual

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Chapter 9. The GRUB Boot Loader
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uses the specified alternate configuration file to build the menu. If an alternate menu configuration
file is left out of the command, a user who knows the password is allowed to edit the current
configuration file.
For more information about securing GRUB, refer to the chapter titled
Workstation Security
in the
Red Hat Enterprise Linux Deployment Guide
.
•
root ( <device-type><device-number> , <partition> )
— Configures the root partition for
GRUB, such as
(hd0,0)
, and mounts the partition.
•
rootnoverify ( <device-type><device-number> , <partition> )
— Configures the root
partition for GRUB, just like the
root
command, but does not mount the partition.
•
timeout= <integer>
— Specifies the interval, in seconds, that GRUB waits before loading the
entry designated in the
default
command.
•
splashimage= <path-to-image>
— Specifies the location of the splash screen image to be
used when GRUB boots.
•
title group-title
— Specifies a title to be used with a particular group of commands used to
load a kernel or operating system.
To add human-readable comments to the menu configuration file, begin the line with the hash mark
character (
#
).
9.8. Changing Runlevels at Boot Time
Under Red Hat Enterprise Linux, it is possible to change the default runlevel at boot time.
To change the runlevel of a single boot session, use the following instructions:
• When the GRUB menu bypass screen appears at boot time, press any key to enter the GRUB menu
(within the first three seconds).
• Press the
a
key to append to the
kernel
command.
• Add
<space> <runlevel>
at the end of the boot options line to boot to the desired runlevel. For
example, the following entry would initiate a boot process into runlevel 3:
grub append> ro root=/dev/VolGroup00/LogVol00 rhgb quiet 3
9.9. Additional Resources
This chapter is only intended as an introduction to GRUB. Consult the following resources to discover
more about how GRUB works.
9.9.1. Installed Documentation
•
/usr/share/doc/grub- <version-number> /
— This directory contains good information about
using and configuring GRUB, where
<version-number>
corresponds to the version of the GRUB
package installed.