menulst（Menulst - GRUB Legacy Configuration）

GRUB Legacy is a bootloader that is widely used on Linux systems. The configuration file for GRUB Legacy is menu.lst, which is located in the /boot/grub directory. The menu.lst file defines the operating systems that are available for booting, the options for those operating systems, and the boot order. In this article, we will discuss the three main sections of the menu.lst file and provide examples of how to configure them.

Section 1 - Global Settings

The global settings section is the first section in the menu.lst file. It contains the settings that apply to all operating system entries. The most important settings in this section are default, timeout, and hiddenmenu.

The default setting specifies the default operating system that will be booted if the user does not select one within the timeout period. The value for this setting is the index number of the operating system entry in the menu.lst file. For example, if the first entry in the file is for Ubuntu, then the default value would be 0.

The timeout setting specifies the number of seconds that the GRUB menu will be displayed before it automatically boots the default operating system. The value for this setting is in seconds. For example, if the timeout is set to 5, then the menu will be displayed for 5 seconds.

The hiddenmenu setting specifies whether the GRUB menu should be hidden. If this setting is set to true, then the menu will not be displayed unless the user presses a key during the timeout period.

Section 2 - Operating System Entries

The operating system entries section is where each operating system is defined. Each entry includes the operating system name, kernel file location, and kernel options. Here is an example entry for Ubuntu:

title Ubuntu 18.04
root (hd0,0)
kernel /boot/vmlinuz-4.15.0-43-generic root=/dev/sda1 ro quiet splash
initrd /boot/initrd.img-4.15.0-43-generic

The title field specifies the name of the operating system that will be displayed in the GRUB menu. The root field specifies the partition where the operating system is installed. The kernel field specifies the location of the kernel file and any options that should be passed to the kernel. The initrd field specifies the location of the initial RAM disk file, which is used during the boot process.

Section 3 - Additional Configuration

The additional configuration section is where you can include any additional configuration that is specific to your system. For example, you can define custom menu entries, set default options for kernel parameters, or specify options for specific hardware. Here is an example of how to define a custom menu entry:

title Memtest86+
kernel /boot/memtest86+.bin

This entry will add a new option to the GRUB menu that will run the Memtest86+ memory diagnostic tool when selected.

In conclusion, the menu.lst file is an essential part of configuring the GRUB Legacy bootloader. By understanding the three main sections of the file, you can customize the boot process to fit your system’s needs. We hope that this article has provided you with the knowledge to modify your menu.lst file with confidence.