Misplaced Pages

Boot folder

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.
Directory in Unix-like operating systems
This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these messages)
This article's lead section may be too short to adequately summarize the key points. Please consider expanding the lead to provide an accessible overview of all important aspects of the article. (December 2024)
This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.
Find sources: "Boot folder" – news · newspapers · books · scholar · JSTOR (June 2010) (Learn how and when to remove this message)
This article contains instructions, advice, or how-to content. Please help rewrite the content so that it is more encyclopedic or move it to Wikiversity, Wikibooks, or Wikivoyage. (December 2024)
(Learn how and when to remove this message)

In Unix-like operating systems, a boot folder is the directory which holds files used in booting the operating system, typically /boot. The usage is standardized within Linux in the Filesystem Hierarchy Standard.

Contents

The contents are mostly Linux kernel files or boot loader files, depending on the boot loader, most commonly (on Linux) LILO or GRUB.

Linux

  • vmlinux – the Linux kernel
  • initrd.img – a temporary file system, used prior to loading the kernel
  • System.map – a symbol lookup table

LILO

LILO creates and uses the following files:

  • map – a key file, which records where files needed by LILO during boot are stored. Following kernel upgrades, this file must be regenerated by running the "map installer", which is /sbin/lilo otherwise the system will not boot.
  • boot.xxyy – these 512-byte files are backups of boot sectors, either the master boot record (MBR) or volume boot record (VBR), created when LILO overwrites a boot sector. xx and yy are the major and minor device numbers in hex; for example, the drive sda has numbers 8, 0, hence its MBR is backed up to boot.0800 while the partition sda3 has numbers 8,3, hence its VBR is backed up to boot.0803.

LILO may also use other files, such as message and also stores a non-boot configuration file in /etc/lilo.conf.

GRUB

GRUB stores its files in the subdirectory grub/ (i.e. /boot/grub/). These files are mostly modules (.mod), with configuration stored in grub.cfg.

Location

/boot/ is often simply a directory on the main (or only) hard drive partition. However, it may be a separate partition. A separate partition is generally only used when bootloaders are incapable of reading the main filesystem (e.g. LILO does not recognize XFS) or other problems not easily resolvable by users.

On UEFI systems, including most modern PCs, the EFI system partition is often mounted at /boot/, /efi/ or /boot/efi/.

References

  1. "3.5. /boot : Static files of the boot loader". Linux Foundation Referenced Specifications. March 19, 2015. Retrieved June 7, 2021.
  2. Ward, Brian (2004). How Linux works what every superuser should know. San Francisco: No Starch Press. p. 219. ISBN 1593270356.
  3. Lombardo, John (2001). Embedded Linux. Indianapolis, Ind: New Riders. p. 17. ISBN 9780735709980.
  4. Kopper, Karl (2008). The Linux Enterprise Cluster build a highly available cluster with commodity hardware and free software. San Francisco: No Starch Press. p. 61. ISBN 978-1593270360.
  5. "LILO mini-HOWTO: Background Information and Standard Installation". tldp.org. Retrieved 2022-11-26.
  6. "EFI System Partition - Gentoo wiki". wiki.gentoo.org. Retrieved 2024-02-15.
  7. "EFI system partition - ArchWiki". wiki.archlinux.org. Retrieved 2024-02-15.


Stub icon

This article related to a type of software is a stub. You can help Misplaced Pages by expanding it.

Categories: