Which file contains the boot related information in Linux?

There isn't a single file that contains *all* boot related information in Linux. Instead, the boot process involves multiple files and configurations spread across several directories:

1. /boot directory:

* vmlinuz: This file contains the Linux kernel itself, which is loaded into memory during boot.

* initrd.img (or initramfs.img): This file contains the initial ramdisk, which is a small, self-contained filesystem that is loaded before the main root filesystem is mounted. It contains drivers and utilities needed for early boot stages.

* grub.cfg (or grub2.cfg): This file contains the configuration for the GRUB bootloader. It defines the boot menu, kernel parameters, and other boot-related options.

* config- files: These files contain the configuration information for various kernel modules.

* System.map: This file maps kernel symbols to their memory addresses.

2. /etc directory:

* fstab: This file defines the file systems that are mounted at boot time, including the root filesystem.

* rc.local (or rc.sysinit): This file contains scripts that are run at boot time.

* mtab: This file stores the current mount points for all mounted filesystems.

3. /sys directory:

* firmware/efi/efivars/ directory: This directory contains EFI variables which store boot-related configuration information.

* devices/virtual/disk/by-id directory: This directory contains symlinks to device files for hard drives and partitions, which are used for boot.

4. BIOS/UEFI firmware:

* The BIOS or UEFI firmware also contains boot-related settings, such as boot order and hard drive settings.

5. Other files:

* /proc/cmdline: This file contains the kernel command line parameters passed to the kernel at boot time.

* /var/log/boot.log: This file logs boot messages.

Important points to note:

* The boot process is complex and involves interaction between multiple components.

* The specific files and directories involved can vary depending on the Linux distribution and boot loader used.

* Modifying boot files requires careful attention and should only be done by experienced users.

It's best to consult your distribution's documentation for specific information regarding boot files and their configuration.