Grub Interfaces - Red Hat ENTERPRISE LINUX 3 Reference Manual

Chapter 2. Boot Loaders
The following shows the
command line after setting the correct device and partition as root:
chainloader +1
2.4.3. The Root File System and GRUB
The use of the term root file system has a different meaning in regard to GRUB. It is important to
remember that GRUB's root file system has nothing to do with the Linux root file system.
The GRUB root file system is the top level of the specified device. For example, the image file
(hd0,0)/grub/splash.xpm.gz
of the partition (which is actually the
(hd0,0)
Once GRUB has loaded its root partition (which equates to the
kernel), the
kernel
the Linux kernel boots, it sets up the root file system that Linux users are familiar with. The original
GRUB root file system and its mounts are forgotten; they only existed to boot the kernel file.
Refer to the and
root

2.5. GRUB Interfaces

GRUB features three interfaces which provide different levels of functionality. Each of these interfaces
allows users to boot the Linux kernel or another operating system.
The interfaces are as follows:
Menu Interface
This is the default interface shown when GRUB is configured by the installation program, this
is the interface shown by default. A menu of operating systems or kernels preconfigured are
displayed as a list, ordered by name. Use the arrow keys to select an option other than the default
selection and press the [Enter] key to boot it. Alternatively, a timeout period is set, after which
GRUB loads the default option.
Press the [e] key to enter the entry editor interface or the [c] key to load a command line interface.
Refer to Section 2.7 GRUB Menu Configuration File for more information on configuring this
interface.
Menu Entry Editor Interface
To access the menu entry editor, press the [e] key from the boot loader menu. The GRUB com-
mands for that entry are displayed here, and users may alter these command lines before booting
the operating system by adding a command line ([o] inserts a new line after the current line and
[O] inserts a new line before it), editing one ([e]), or deleting one ([d]).
After all changes are made, the [b] key executes the commands and boots the operating system.
The [Esc] key discards any changes and reloads the standard menu interface. The [c] key loads
the command line interface.
Tip
For information about changing runlevels with GRUB using the menu entry editor, refer to Sec-
tion 2.10 Changing Runlevels at Boot Time.
command with a similar blocklist designation at the GRUB
chainloader
is located within the
command can be executed with the location of the kernel file as an option. Once
commands in Section 2.6 GRUB Commands for more information.
kernel
directory at the top-level (or root)
/grub/
partition for the system).
/boot/
/boot
partition and contains the Linux
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