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- Committer: Bazaar Package Importer
- Author(s): Colin Watson
- Date: 2011-01-17 13:43:06 UTC
- mto: (17.6.26 experimental)
- mto: This revision was merged to the branch mainline in revision 102.
- Revision ID: james.westby@ubuntu.com-20110117134306-fy7qewn4s3qdx2pl
Tags: upstream-1.99~rc1
Import upstream version 1.99~rc1
- files added:
- Makefile.in
- autom4te.cache
- grub-core/lib/libgcrypt-grub
- grub-core/lib/libgcrypt-grub/cipher
- files removed:
- po/LINGUAS
- files modified:
- .bzrignore
added
removed
docs/grub.info
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This is /home/phcoder/grub2/bzr/mainline/docs/grub.info, produced by
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makeinfo version 4.13 from
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/home/phcoder/grub2/bzr/mainline/docs/grub.texi.
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This manual is for GNU GRUB (version 1.99~rc1, 8 January 2011).
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Copyright (C) 1999,2000,2001,2002,2004,2006,2008,2009,2010 Free
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Software Foundation, Inc.
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Permission is granted to copy, distribute and/or modify this
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document under the terms of the GNU Free Documentation License,
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Version 1.2 or any later version published by the Free Software
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Foundation; with no Invariant Sections.
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INFO-DIR-SECTION Kernel
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START-INFO-DIR-ENTRY
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* GRUB: (grub). The GRand Unified Bootloader
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* grub-install: (grub)Invoking grub-install. Install GRUB on your drive
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* grub-mkconfig: (grub)Invoking grub-mkconfig. Generate GRUB configuration
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* grub-mkpasswd-pbkdf2: (grub)Invoking grub-mkpasswd-pbkdf2.
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END-INFO-DIR-ENTRY
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File: grub.info, Node: Top, Next: Introduction, Up: (dir)
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GNU GRUB manual
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***************
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This is the documentation of GNU GRUB, the GRand Unified Bootloader, a
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flexible and powerful boot loader program for a wide range of
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architectures.
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This edition documents version 1.99~rc1.
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This manual is for GNU GRUB (version 1.99~rc1, 8 January 2011).
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Copyright (C) 1999,2000,2001,2002,2004,2006,2008,2009,2010 Free
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Software Foundation, Inc.
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Permission is granted to copy, distribute and/or modify this
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document under the terms of the GNU Free Documentation License,
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Version 1.2 or any later version published by the Free Software
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Foundation; with no Invariant Sections.
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* Menu:
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* Introduction:: Capturing the spirit of GRUB
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* Naming convention:: Names of your drives in GRUB
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* Installation:: Installing GRUB on your drive
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* Booting:: How to boot different operating systems
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* Configuration:: Writing your own configuration file
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* Theme file format:: Format of GRUB theme files
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* Network:: Downloading OS images from a network
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* Serial terminal:: Using GRUB via a serial line
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* Vendor power-on keys:: Changing GRUB behaviour on vendor power-on keys
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* Images:: GRUB image files
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* Filesystem:: Filesystem syntax and semantics
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* Interface:: The menu and the command-line
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* Commands:: The list of available builtin commands
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* Security:: Authentication and authorisation
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* Supported kernels:: The list of supported kernels
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* Troubleshooting:: Error messages produced by GRUB
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* Invoking grub-install:: How to use the GRUB installer
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* Invoking grub-mkconfig:: Generate a GRUB configuration file
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* Invoking grub-mkpasswd-pbkdf2::
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Generate GRUB password hashes
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* Obtaining and Building GRUB:: How to obtain and build GRUB
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* Reporting bugs:: Where you should send a bug report
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* Future:: Some future plans on GRUB
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* Internals:: Hacking GRUB
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* Copying This Manual:: Copying This Manual
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* Index::
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File: grub.info, Node: Introduction, Next: Naming convention, Prev: Top, Up: Top
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1 Introduction to GRUB
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**********************
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* Menu:
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* Overview:: What exactly GRUB is and how to use it
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* History:: From maggot to house fly
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* Changes from GRUB Legacy:: Differences from previous versions
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* Features:: GRUB features
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* Role of a boot loader:: The role of a boot loader
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File: grub.info, Node: Overview, Next: History, Up: Introduction
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1.1 Overview
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============
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Briefly, a "boot loader" is the first software program that runs when a
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computer starts. It is responsible for loading and transferring
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control to an operating system "kernel" software (such as Linux or GNU
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Mach). The kernel, in turn, initializes the rest of the operating
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system (e.g. a GNU system).
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GNU GRUB is a very powerful boot loader, which can load a wide
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variety of free operating systems, as well as proprietary operating
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systems with chain-loading(1) (*note Overview-Footnote-1::). GRUB is
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designed to address the complexity of booting a personal computer; both
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the program and this manual are tightly bound to that computer platform,
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although porting to other platforms may be addressed in the future.
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One of the important features in GRUB is flexibility; GRUB
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understands filesystems and kernel executable formats, so you can load
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an arbitrary operating system the way you like, without recording the
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physical position of your kernel on the disk. Thus you can load the
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kernel just by specifying its file name and the drive and partition
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where the kernel resides.
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When booting with GRUB, you can use either a command-line interface
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(*note Command-line interface::), or a menu interface (*note Menu
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interface::). Using the command-line interface, you type the drive
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specification and file name of the kernel manually. In the menu
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interface, you just select an OS using the arrow keys. The menu is
119
based on a configuration file which you prepare beforehand (*note
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Configuration::). While in the menu, you can switch to the command-line
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mode, and vice-versa. You can even edit menu entries before using them.
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In the following chapters, you will learn how to specify a drive, a
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partition, and a file name (*note Naming convention::) to GRUB, how to
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install GRUB on your drive (*note Installation::), and how to boot your
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OSes (*note Booting::), step by step.
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File: grub.info, Node: Overview-Footnotes, Up: Overview
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(1) "chain-load" is the mechanism for loading unsupported operating
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systems by loading another boot loader. It is typically used for
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loading DOS or Windows.
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File: grub.info, Node: History, Next: Changes from GRUB Legacy, Prev: Overview, Up: Introduction
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1.2 History of GRUB
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===================
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GRUB originated in 1995 when Erich Boleyn was trying to boot the GNU
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Hurd with the University of Utah's Mach 4 microkernel (now known as GNU
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Mach). Erich and Brian Ford designed the Multiboot Specification
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(*note Multiboot Specification: (multiboot)Top.), because they were
145
determined not to add to the large number of mutually-incompatible PC
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boot methods.
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Erich then began modifying the FreeBSD boot loader so that it would
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understand Multiboot. He soon realized that it would be a lot easier to
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write his own boot loader from scratch than to keep working on the
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FreeBSD boot loader, and so GRUB was born.
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Erich added many features to GRUB, but other priorities prevented him
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from keeping up with the demands of its quickly-expanding user base. In
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1999, Gordon Matzigkeit and Yoshinori K. Okuji adopted GRUB as an
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official GNU package, and opened its development by making the latest
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sources available via anonymous CVS. *Note Obtaining and Building
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GRUB::, for more information.
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Over the next few years, GRUB was extended to meet many needs, but it
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quickly became clear that its design was not keeping up with the
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extensions being made to it, and we reached the point where it was very
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difficult to make any further changes without breaking existing
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features. Around 2002, Yoshinori K. Okuji started work on PUPA
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(Preliminary Universal Programming Architecture for GNU GRUB), aiming
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to rewrite the core of GRUB to make it cleaner, safer, more robust, and
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more powerful. PUPA was eventually renamed to GRUB 2, and the original
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version of GRUB was renamed to GRUB Legacy. Small amounts of
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maintenance continued to be done on GRUB Legacy, but the last release
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(0.97) was made in 2005 and at the time of writing it seems unlikely
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that there will be another.
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By around 2007, GNU/Linux distributions started to use GRUB 2 to
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limited extents, and by the end of 2009 multiple major distributions
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were installing it by default.
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File: grub.info, Node: Changes from GRUB Legacy, Next: Features, Prev: History, Up: Introduction
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1.3 Differences from previous versions
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======================================
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GRUB 2 is a rewrite of GRUB (*note History::), although it shares many
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characteristics with the previous version, now known as GRUB Legacy.
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Users of GRUB Legacy may need some guidance to find their way around
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this new version.
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* The configuration file has a new name (`grub.cfg' rather than
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`menu.lst' or `grub.conf'), new syntax (*note Configuration::) and
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many new commands (*note Commands::). Configuration cannot be
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copied over directly, although most GRUB Legacy users should not
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find the syntax too surprising.
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* `grub.cfg' is typically automatically generated by `grub-mkconfig'
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(*note Simple configuration::). This makes it easier to handle
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versioned kernel upgrades.
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* Partition numbers in GRUB device names now start at 1, not 0
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(*note Naming convention::).
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* The configuration file is now written in something closer to a full
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scripting language: variables, conditionals, and loops are
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available.
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* A small amount of persistent storage is available across reboots,
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using the `save_env' and `load_env' commands in GRUB and the
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`grub-editenv' utility. For safety reasons this storage is only
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available when installed on plain disk (no LVM or RAID), using
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non-checksumming filesystem (no ZFS) and using BIOS or EFI
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functions (no ATA, USB or IEEE1275)
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* GRUB 2 has more reliable ways to find its own files and those of
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target kernels on multiple-disk systems, and has commands (*note
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search::) to find devices using file system labels or Universally
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Unique Identifiers (UUIDs).
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* GRUB 2 is available for several other types of system in addition
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to the PC BIOS systems supported by GRUB Legacy: PC EFI, PC
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coreboot, PowerPC, SPARC, and MIPS Lemote Yeeloong are all
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supported.
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* Many more file systems are supported, including but not limited to
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ext4, HFS+, and NTFS.
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* GRUB 2 can read files directly from LVM and RAID devices.
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* A graphical terminal and a graphical menu system are available.
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* GRUB 2's interface can be translated, including menu entry names.
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* The image files (*note Images::) that make up GRUB have been
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reorganised; Stage 1, Stage 1.5, and Stage 2 are no more.
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* GRUB 2 puts many facilities in dynamically loaded modules,
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allowing the core image to be smaller, and allowing the core image
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to be built in more flexible ways.
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File: grub.info, Node: Features, Next: Role of a boot loader, Prev: Changes from GRUB Legacy, Up: Introduction
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1.4 GRUB features
242
=================
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The primary requirement for GRUB is that it be compliant with the
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"Multiboot Specification", which is described in *note Multiboot
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Specification: (multiboot)Top.
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The other goals, listed in approximate order of importance, are:
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* Basic functions must be straightforward for end-users.
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* Rich functionality to support kernel experts and designers.
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* Backward compatibility for booting FreeBSD, NetBSD, OpenBSD, and
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Linux. Proprietary kernels (such as DOS, Windows NT, and OS/2) are
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supported via a chain-loading function.
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Except for specific compatibility modes (chain-loading and the Linux
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"piggyback" format), all kernels will be started in much the same state
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as in the Multiboot Specification. Only kernels loaded at 1 megabyte or
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above are presently supported. Any attempt to load below that boundary
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will simply result in immediate failure and an error message reporting
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the problem.
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In addition to the requirements above, GRUB has the following
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features (note that the Multiboot Specification doesn't require all the
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features that GRUB supports):
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Recognize multiple executable formats
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Support many of the "a.out" variants plus "ELF". Symbol tables are
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also loaded.
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Support non-Multiboot kernels
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Support many of the various free 32-bit kernels that lack Multiboot
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compliance (primarily FreeBSD, NetBSD, OpenBSD, and Linux).
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Chain-loading of other boot loaders is also supported.
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Load multiples modules
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Fully support the Multiboot feature of loading multiple modules.
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Load a configuration file
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Support a human-readable text configuration file with preset boot
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commands. You can also load another configuration file dynamically
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and embed a preset configuration file in a GRUB image file. The
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list of commands (*note Commands::) are a superset of those
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supported on the command-line. An example configuration file is
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provided in *note Configuration::.
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Provide a menu interface
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A menu interface listing preset boot commands, with a programmable
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timeout, is available. There is no fixed limit on the number of
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boot entries, and the current implementation has space for several
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hundred.
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Have a flexible command-line interface
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A fairly flexible command-line interface, accessible from the menu,
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is available to edit any preset commands, or write a new boot
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command set from scratch. If no configuration file is present,
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GRUB drops to the command-line.
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The list of commands (*note Commands::) are a subset of those
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supported for configuration files. Editing commands closely
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resembles the Bash command-line (*note Bash: (features)Command
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Line Editing.), with <TAB>-completion of commands, devices,
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partitions, and files in a directory depending on context.
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Support multiple filesystem types
308
Support multiple filesystem types transparently, plus a useful
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explicit blocklist notation. The currently supported filesystem
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types are "Amiga Fast FileSystem (AFFS)", "AtheOS fs", "BeFS",
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"cpio", "Linux ext2/ext3/ext4", "DOS FAT12/FAT16/FAT32", "HFS",
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"HFS+", "ISO9660", "JFS", "Minix fs", "nilfs2", "NTFS",
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"ReiserFS", "Amiga Smart FileSystem (SFS)", "tar", "UDF", "BSD
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UFS/UFS2", and "XFS". *Note Filesystem::, for more information.
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Support automatic decompression
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Can decompress files which were compressed by `gzip' or `xz'(1)
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(*note Features-Footnote-1::). This function is both automatic and
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transparent to the user (i.e. all functions operate upon the
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uncompressed contents of the specified files). This greatly
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reduces a file size and loading time, a particularly great benefit
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for floppies.(2) (*note Features-Footnote-2::)
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It is conceivable that some kernel modules should be loaded in a
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compressed state, so a different module-loading command can be
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specified to avoid uncompressing the modules.
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Access data on any installed device
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Support reading data from any or all floppies or hard disk(s)
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recognized by the BIOS, independent of the setting of the root
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device.
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Be independent of drive geometry translations
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Unlike many other boot loaders, GRUB makes the particular drive
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translation irrelevant. A drive installed and running with one
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translation may be converted to another translation without any
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adverse effects or changes in GRUB's configuration.
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Detect all installed RAM
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GRUB can generally find all the installed RAM on a PC-compatible
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machine. It uses an advanced BIOS query technique for finding all
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memory regions. As described on the Multiboot Specification (*note
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Multiboot Specification: (multiboot)Top.), not all kernels make
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use of this information, but GRUB provides it for those who do.
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Support Logical Block Address mode
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In traditional disk calls (called "CHS mode"), there is a geometry
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translation problem, that is, the BIOS cannot access over 1024
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cylinders, so the accessible space is limited to at least 508 MB
350
and to at most 8GB. GRUB can't universally solve this problem, as
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there is no standard interface used in all machines. However,
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several newer machines have the new interface, Logical Block
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Address ("LBA") mode. GRUB automatically detects if LBA mode is
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available and uses it if available. In LBA mode, GRUB can access
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the entire disk.
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Support network booting
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GRUB is basically a disk-based boot loader but also has network
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support. You can load OS images from a network by using the "TFTP"
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protocol.
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Support remote terminals
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To support computers with no console, GRUB provides remote terminal
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support, so that you can control GRUB from a remote host. Only
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serial terminal support is implemented at the moment.
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File: grub.info, Node: Features-Footnotes, Up: Features
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(1) Only CRC32 data integrity check is supported (xz default is
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CRC64 so one should use -check=crc32 option). LZMA BCJ filters are
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supported.
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(2) There are a few pathological cases where loading a very badly
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organized ELF kernel might take longer, but in practice this never
376
happen.
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File: grub.info, Node: Role of a boot loader, Prev: Features, Up: Introduction
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1.5 The role of a boot loader
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=============================
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The following is a quotation from Gordon Matzigkeit, a GRUB fanatic:
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Some people like to acknowledge both the operating system and
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kernel when they talk about their computers, so they might say
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they use "GNU/Linux" or "GNU/Hurd". Other people seem to think
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that the kernel is the most important part of the system, so they
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like to call their GNU operating systems "Linux systems."
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I, personally, believe that this is a grave injustice, because the
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_boot loader_ is the most important software of all. I used to
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refer to the above systems as either "LILO"(1) (*note Role of a
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boot loader-Footnote-1::) or "GRUB" systems.
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Unfortunately, nobody ever understood what I was talking about;
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now I just use the word "GNU" as a pseudonym for GRUB.
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So, if you ever hear people talking about their alleged "GNU"
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systems, remember that they are actually paying homage to the best
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boot loader around... GRUB!
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We, the GRUB maintainers, do not (usually) encourage Gordon's level
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of fanaticism, but it helps to remember that boot loaders deserve
406
recognition. We hope that you enjoy using GNU GRUB as much as we did
407
writing it.
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File: grub.info, Node: Role of a boot loader-Footnotes, Up: Role of a boot loader
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(1) The LInux LOader, a boot loader that everybody uses, but nobody
413
likes.
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File: grub.info, Node: Naming convention, Next: Installation, Prev: Introduction, Up: Top
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2 Naming convention
419
*******************
420
421
The device syntax used in GRUB is a wee bit different from what you may
422
have seen before in your operating system(s), and you need to know it so
423
that you can specify a drive/partition.
424
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Look at the following examples and explanations:
426
427
(fd0)
428
429
First of all, GRUB requires that the device name be enclosed with
430
`(' and `)'. The `fd' part means that it is a floppy disk. The number
431
`0' is the drive number, which is counted from _zero_. This expression
432
means that GRUB will use the whole floppy disk.
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(hd0,msdos2)
435
436
Here, `hd' means it is a hard disk drive. The first integer `0'
437
indicates the drive number, that is, the first hard disk, the string
438
`msdos' indicates the partition scheme, while the second integer, `2',
439
indicates the partition number (or the PC slice number in the BSD
440
terminology). The partition numbers are counted from _one_, not from
441
zero (as was the case in previous versions of GRUB). This expression
442
means the second partition of the first hard disk drive. In this case,
443
GRUB uses one partition of the disk, instead of the whole disk.
444
445
(hd0,msdos5)
446
447
This specifies the first "extended partition" of the first hard disk
448
drive. Note that the partition numbers for extended partitions are
449
counted from `5', regardless of the actual number of primary partitions
450
on your hard disk.
451
452
(hd1,msdos1,bsd1)
453
454
This means the BSD `a' partition on first PC slice number of the
455
second hard disk.
456
457
Of course, to actually access the disks or partitions with GRUB, you
458
need to use the device specification in a command, like `set
459
root=(fd0)' or `parttool (hd0,msdos3) hidden-'. To help you find out
460
which number specifies a partition you want, the GRUB command-line
461
(*note Command-line interface::) options have argument completion. This
462
means that, for example, you only need to type
463
464
set root=(
465
466
followed by a <TAB>, and GRUB will display the list of drives,
467
partitions, or file names. So it should be quite easy to determine the
468
name of your target partition, even with minimal knowledge of the
469
syntax.
470
471
Note that GRUB does _not_ distinguish IDE from SCSI - it simply
472
counts the drive numbers from zero, regardless of their type. Normally,
473
any IDE drive number is less than any SCSI drive number, although that
474
is not true if you change the boot sequence by swapping IDE and SCSI
475
drives in your BIOS.
476
477
Now the question is, how to specify a file? Again, consider an
478
example:
479
480
(hd0,msdos1)/vmlinuz
481
482
This specifies the file named `vmlinuz', found on the first
483
partition of the first hard disk drive. Note that the argument
484
completion works with file names, too.
485
486
That was easy, admit it. Now read the next chapter, to find out how
487
to actually install GRUB on your drive.
488
489
490
File: grub.info, Node: Installation, Next: Booting, Prev: Naming convention, Up: Top
491
492
3 Installation
493
**************
494
495
In order to install GRUB as your boot loader, you need to first install
496
the GRUB system and utilities under your UNIX-like operating system
497
(*note Obtaining and Building GRUB::). You can do this either from the
498
source tarball, or as a package for your OS.
499
500
After you have done that, you need to install the boot loader on a
501
drive (floppy or hard disk). There are two ways of doing that - either
502
using the utility `grub-install' (*note Invoking grub-install::) on a
503
UNIX-like OS, or by running GRUB itself from a floppy. These are quite
504
similar, however the utility might probe a wrong BIOS drive, so you
505
should be careful.
506
507
Also, if you install GRUB on a UNIX-like OS, please make sure that
508
you have an emergency boot disk ready, so that you can rescue your
509
computer if, by any chance, your hard drive becomes unusable
510
(unbootable).
511
512
GRUB comes with boot images, which are normally put in the directory
513
`/usr/lib/grub/i386-pc'. Hereafter, the directory where GRUB images are
514
initially placed (normally `/usr/lib/grub/i386-pc') will be called the
515
"image directory", and the directory where the boot loader needs to
516
find them (usually `/boot/grub') will be called the "boot directory".
517
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* Menu:
519
520
* Installing GRUB using grub-install::
521
* Making a GRUB bootable CD-ROM::
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* Device map::
523
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File: grub.info, Node: Installing GRUB using grub-install, Next: Making a GRUB bootable CD-ROM, Up: Installation
526
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3.1 Installing GRUB using grub-install
528
======================================
529
530
*Caution:* This procedure is definitely less safe, because there are
531
several ways in which your computer can become unbootable. For example,
532
most operating systems don't tell GRUB how to map BIOS drives to OS
533
devices correctly--GRUB merely "guesses" the mapping. This will succeed
534
in most cases, but not always. Therefore, GRUB provides you with a map
535
file called the "device map", which you must fix if it is wrong. *Note
536
Device map::, for more details.
537
538
On BIOS platforms GRUB has to use a so-called embedding zone. On
539
msdos partition tables, this is the space between the MBR and the first
540
partition (called the MBR gap or the boot track), while on GPT
541
partition tables it uses a BIOS Boot Partition (a partition with GUID
542
21686148-6449-6e6f-744e656564454649). If you use GRUB on a BIOS system,
543
make sure that the embedding zone is at least 31 KiB (512KiB or more
544
recommended).
545
546
If you still do want to install GRUB under a UNIX-like OS (such as
547
GNU), invoke the program `grub-install' (*note Invoking grub-install::)
548
as the superuser ("root").
549
550
The usage is basically very simple. You only need to specify one
551
argument to the program, namely, where to install the boot loader. The
552
argument can be either a device file (like `/dev/hda') or a partition
553
specified in GRUB's notation. For example, under Linux the following
554
will install GRUB into the MBR of the first IDE disk:
555
556
# grub-install /dev/hda
557
558
Likewise, under GNU/Hurd, this has the same effect:
559
560
# grub-install /dev/hd0
561
562
But all the above examples assume that GRUB should use images under
563
the root directory. If you want GRUB to use images under a directory
564
other than the root directory, you need to specify the option
565
`--root-directory'. The typical usage is that you create a GRUB boot
566
floppy with a filesystem. Here is an example:
567
568
# mke2fs /dev/fd0
569
# mount -t ext2 /dev/fd0 /mnt
570
# grub-install --root-directory=/mnt fd0
571
# umount /mnt
572
573
Another example is when you have a separate boot partition which is
574
mounted at `/boot'. Since GRUB is a boot loader, it doesn't know
575
anything about mountpoints at all. Thus, you need to run `grub-install'
576
like this:
577
578
# grub-install --root-directory=/boot /dev/hda
579
580
By the way, as noted above, it is quite difficult to guess BIOS
581
drives correctly under a UNIX-like OS. Thus, `grub-install' will prompt
582
you to check if it could really guess the correct mappings, after the
583
installation. The format is defined in *note Device map::. Please be
584
quite careful. If the output is wrong, it is unlikely that your
585
computer will be able to boot with no problem.
586
587
Some BIOSes have a bug of exposing the first partition of a USB
588
drive as a floppy instead of exposing the USB drive as a hard disk
589
(they call it "USB-FDD" boot). In such cases, you need to install like
590
this:
591
592
# losetup /dev/loop0 /dev/sdb1
593
# mount /dev/loop0 /mnt/usb
594
# grub-install --boot-directory=/mnt/usb/bugbios --force --allow-floppy /dev/loop0
595
596
This install doesn't conflict with standard install as long as they
597
are in separate directories.
598
599
Note that `grub-install' is actually just a shell script and the
600
real task is done by `grub-mkimage' and `grub-setup'. Therefore, you
601
may run those commands directly to install GRUB, without using
602
`grub-install'. Don't do that, however, unless you are very familiar
603
with the internals of GRUB. Installing a boot loader on a running OS
604
may be extremely dangerous.
605
606
607
File: grub.info, Node: Making a GRUB bootable CD-ROM, Next: Device map, Prev: Installing GRUB using grub-install, Up: Installation
608
609
3.2 Making a GRUB bootable CD-ROM
610
=================================
611
612
GRUB supports the "no emulation mode" in the El Torito specification(1)
613
(*note Making a GRUB bootable CD-ROM-Footnote-1::). This means that you
614
can use the whole CD-ROM from GRUB and you don't have to make a floppy
615
or hard disk image file, which can cause compatibility problems.
616
617
For booting from a CD-ROM, GRUB uses a special Stage 2 called
618
`stage2_eltorito'. The only GRUB files you need to have in your
619
bootable CD-ROM are this `stage2_eltorito' and optionally a config file
620
`grub.cfg'. You don't need to use `stage1' or `stage2', because El
621
Torito is quite different from the standard boot process.
622
623
Here is an example of procedures to make a bootable CD-ROM image.
624
First, make a top directory for the bootable image, say, `iso':
625
626
$ mkdir iso
627
628
Make a directory for GRUB:
629
630
$ mkdir -p iso/boot/grub
631
632
Copy the file `stage2_eltorito':
633
634
$ cp /usr/lib/grub/i386-pc/stage2_eltorito iso/boot/grub
635
636
If desired, make the config file `grub.cfg' under `iso/boot/grub'
637
(*note Configuration::), and copy any files and directories for the
638
disc to the directory `iso/'.
639
640
Finally, make a ISO9660 image file like this:
641
642
$ mkisofs -R -b boot/grub/stage2_eltorito -no-emul-boot \
643
-boot-load-size 4 -boot-info-table -o grub.iso iso
644
645
This produces a file named `grub.iso', which then can be burned into
646
a CD (or a DVD). `mkisofs' has already set up the disc to boot from
647
the `boot/grub/stage2_eltorito' file, so there is no need to setup GRUB
648
on the disc. (Note that the `-boot-load-size 4' bit is required for
649
compatibility with the BIOS on many older machines.)
650
651
You can use the device `(cd)' to access a CD-ROM in your config
652
file. This is not required; GRUB automatically sets the root device to
653
`(cd)' when booted from a CD-ROM. It is only necessary to refer to
654
`(cd)' if you want to access other drives as well.
655
656
657
File: grub.info, Node: Making a GRUB bootable CD-ROM-Footnotes, Up: Making a GRUB bootable CD-ROM
658
659
(1) El Torito is a specification for bootable CD using BIOS
660
functions.
661
662
663
File: grub.info, Node: Device map, Prev: Making a GRUB bootable CD-ROM, Up: Installation
664
665
3.3 The map between BIOS drives and OS devices
666
==============================================
667
668
The `grub-mkdevicemap' program can be used to create the "device map
669
file". It is often run automatically by tools such as `grub-install'
670
if the device map file does not already exist. The file name
671
`/boot/grub/device.map' is preferred.
672
673
If the device map file exists, the GRUB utilities (`grub-probe',
674
`grub-setup', etc.) read it to map BIOS drives to OS devices. This
675
file consists of lines like this:
676
677
DEVICE FILE
678
679
DEVICE is a drive specified in the GRUB syntax (*note Device
680
syntax::), and FILE is an OS file, which is normally a device file.
681
682
Historically, the device map file was used because GRUB device names
683
had to be used in the configuration file, and they were derived from
684
BIOS drive numbers. The map between BIOS drives and OS devices cannot
685
always be guessed correctly: for example, GRUB will get the order wrong
686
if you exchange the boot sequence between IDE and SCSI in your BIOS.
687
688
Unfortunately, even OS device names are not always stable. Modern
689
versions of the Linux kernel may probe drives in a different order from
690
boot to boot, and the prefix (`/dev/hd*' versus `/dev/sd*') may change
691
depending on the driver subsystem in use. As a result, the device map
692
file required frequent editing on some systems.
693
694
GRUB avoids this problem nowadays by using UUIDs or file system
695
labels when generating `grub.cfg', and we advise that you do the same
696
for any custom menu entries you write. If the device map file does not
697
exist, then the GRUB utilities will assume a temporary device map on
698
the fly. This is often good enough, particularly in the common case of
699
single-disk systems.
700
701
However, the device map file is not entirely obsolete yet, and there
702
are still some situations that require it to exist. If necessary, you
703
may edit the file if `grub-mkdevicemap' makes a mistake. You can put
704
any comments in the file if needed, as the GRUB utilities assume that a
705
line is just a comment if the first character is `#'.
706
707
708
File: grub.info, Node: Booting, Next: Configuration, Prev: Installation, Up: Top
709
710
4 Booting
711
*********
712
713
GRUB can load Multiboot-compliant kernels in a consistent way, but for
714
some free operating systems you need to use some OS-specific magic.
715
716
* Menu:
717
718
* General boot methods:: How to boot OSes with GRUB generally
719
* OS-specific notes:: Notes on some operating systems
720
721
722
File: grub.info, Node: General boot methods, Next: OS-specific notes, Up: Booting
723
724
4.1 How to boot operating systems
725
=================================
726
727
GRUB has two distinct boot methods. One of the two is to load an
728
operating system directly, and the other is to chain-load another boot
729
loader which then will load an operating system actually. Generally
730
speaking, the former is more desirable, because you don't need to
731
install or maintain other boot loaders and GRUB is flexible enough to
732
load an operating system from an arbitrary disk/partition. However, the
733
latter is sometimes required, since GRUB doesn't support all the
734
existing operating systems natively.
735
736
* Menu:
737
738
* Loading an operating system directly::
739
* Chain-loading::
740
741
742
File: grub.info, Node: Loading an operating system directly, Next: Chain-loading, Up: General boot methods
743
744
4.1.1 How to boot an OS directly with GRUB
745
------------------------------------------
746
747
Multiboot (*note Multiboot Specification: (multiboot)Top.) is the
748
native format supported by GRUB. For the sake of convenience, there is
749
also support for Linux, FreeBSD, NetBSD and OpenBSD. If you want to
750
boot other operating systems, you will have to chain-load them (*note
751
Chain-loading::).
752
753
FIXME: this section is incomplete.
754
755
1. Run the command `boot' (*note boot::).
756
757
However, DOS and Windows have some deficiencies, so you might have to
758
use more complicated instructions. *Note DOS/Windows::, for more
759
information.
760
761
762
File: grub.info, Node: Chain-loading, Prev: Loading an operating system directly, Up: General boot methods
763
764
4.1.2 Chain-loading an OS
765
-------------------------
766
767
Operating systems that do not support Multiboot and do not have specific
768
support in GRUB (specific support is available for Linux, FreeBSD,
769
NetBSD and OpenBSD) must be chain-loaded, which involves loading
770
another boot loader and jumping to it in real mode.
771
772
The `chainloader' command (*note chainloader::) is used to set this
773
up. It is normally also necessary to load some GRUB modules and set the
774
appropriate root device. Putting this together, we get something like
775
this, for a Windows system on the first partition of the first hard
776
disk:
777
778
menuentry "Windows" {
779
insmod chain
780
insmod ntfs
781
set root=(hd0,1)
782
chainloader +1
783
}
784
785
On systems with multiple hard disks, an additional workaround may be
786
required. *Note DOS/Windows::.
787
788
Chain-loading is only supported on PC BIOS and EFI platforms.
789
790
791
File: grub.info, Node: OS-specific notes, Prev: General boot methods, Up: Booting
792
793
4.2 Some caveats on OS-specific issues
794
======================================
795
796
Here, we describe some caveats on several operating systems.
797
798
* Menu:
799
800
* GNU/Hurd::
801
* GNU/Linux::
802
* DOS/Windows::
803
804
805
File: grub.info, Node: GNU/Hurd, Next: GNU/Linux, Up: OS-specific notes
806
807
4.2.1 GNU/Hurd
808
--------------
809
810
Since GNU/Hurd is Multiboot-compliant, it is easy to boot it; there is
811
nothing special about it. But do not forget that you have to specify a
812
root partition to the kernel.
813
814
1. Set GRUB's root device to the same drive as GNU/Hurd's. The
815
command `search --file --set /boot/gnumach.gz' or similar may help
816
you (*note search::).
817
818
2. Load the kernel and the modules, like this:
819
820
grub> multiboot /boot/gnumach.gz root=device:hd0s1
821
grub> module /hurd/ext2fs.static ext2fs --readonly \
822
--multiboot-command-line='${kernel-command-line}' \
823
--host-priv-port='${host-port}' \
824
--device-master-port='${device-port}' \
825
--exec-server-task='${exec-task}' -T typed '${root}' \
826
'$(task-create)' '$(task-resume)'
827
grub> module /lib/ld.so.1 exec /hurd/exec '$(exec-task=task-create)'
828
829
3. Finally, run the command `boot' (*note boot::).
830
831
832
File: grub.info, Node: GNU/Linux, Next: DOS/Windows, Prev: GNU/Hurd, Up: OS-specific notes
833
834
4.2.2 GNU/Linux
835
---------------
836
837
It is relatively easy to boot GNU/Linux from GRUB, because it somewhat
838
resembles to boot a Multiboot-compliant OS.
839
840
1. Set GRUB's root device to the same drive as GNU/Linux's. The
841
command `search --file --set /vmlinuz' or similar may help you
842
(*note search::).
843
844
2. Load the kernel using the command `linux' (*note linux::):
845
846
grub> linux /vmlinuz root=/dev/sda1
847
848
If you need to specify some kernel parameters, just append them to
849
the command. For example, to set `acpi' to `off', do this:
850
851
grub> linux /vmlinuz root=/dev/sda1 acpi=off
852
853
See the documentation in the Linux source tree for complete
854
information on the available options.
855
856
With `linux' GRUB uses 32-bit protocol. Some BIOS services like APM
857
or EDD aren't available with this protocol. In this case you need
858
to use `linux16'
859
860
grub> linux16 /vmlinuz root=/dev/sda1 acpi=off
861
862
3. If you use an initrd, execute the command `initrd' (*note initrd::)
863
after `linux':
864
865
grub> initrd /initrd
866
867
If you used `linux16' you need to use `initrd16':
868
869
grub> initrd16 /initrd
870
871
4. Finally, run the command `boot' (*note boot::).
872
873
*Caution:* If you use an initrd and specify the `mem=' option to the
874
kernel to let it use less than actual memory size, you will also have
875
to specify the same memory size to GRUB. To let GRUB know the size, run
876
the command `uppermem' _before_ loading the kernel. *Note uppermem::,
877
for more information.
878
879
880
File: grub.info, Node: DOS/Windows, Prev: GNU/Linux, Up: OS-specific notes
881
882
4.2.3 DOS/Windows
883
-----------------
884
885
GRUB cannot boot DOS or Windows directly, so you must chain-load them
886
(*note Chain-loading::). However, their boot loaders have some critical
887
deficiencies, so it may not work to just chain-load them. To overcome
888
the problems, GRUB provides you with two helper functions.
889
890
If you have installed DOS (or Windows) on a non-first hard disk, you
891
have to use the disk swapping technique, because that OS cannot boot
892
from any disks but the first one. The workaround used in GRUB is the
893
command `drivemap' (*note drivemap::), like this:
894
895
drivemap -s (hd0) (hd1)
896
897
This performs a "virtual" swap between your first and second hard
898
drive.
899
900
*Caution:* This is effective only if DOS (or Windows) uses BIOS to
901
access the swapped disks. If that OS uses a special driver for the
902
disks, this probably won't work.
903
904
Another problem arises if you installed more than one set of
905
DOS/Windows onto one disk, because they could be confused if there are
906
more than one primary partitions for DOS/Windows. Certainly you should
907
avoid doing this, but there is a solution if you do want to do so. Use
908
the partition hiding/unhiding technique.
909
910
If GRUB "hides" a DOS (or Windows) partition (*note parttool::), DOS
911
(or Windows) will ignore the partition. If GRUB "unhides" a DOS (or
912
Windows) partition, DOS (or Windows) will detect the partition. Thus,
913
if you have installed DOS (or Windows) on the first and the second
914
partition of the first hard disk, and you want to boot the copy on the
915
first partition, do the following:
916
917
parttool (hd0,1) hidden-
918
parttool (hd0,2) hidden+
919
set root=(hd0,1)
920
chainloader +1
921
parttool ${root} boot+
922
boot
923
924
925
File: grub.info, Node: Configuration, Next: Theme file format, Prev: Booting, Up: Top
926
927
5 Writing your own configuration file
928
*************************************
929
930
GRUB is configured using `grub.cfg', usually located under
931
`/boot/grub'. This file is quite flexible, but most users will not
932
need to write the whole thing by hand.
933
934
* Menu:
935
936
* Simple configuration:: Recommended for most users
937
* Shell-like scripting:: For power users and developers
938
* Embedded configuration:: Embedding a configuration file into GRUB
939
940
941
File: grub.info, Node: Simple configuration, Next: Shell-like scripting, Up: Configuration
942
943
5.1 Simple configuration handling
944
=================================
945
946
The program `grub-mkconfig' (*note Invoking grub-mkconfig::) generates
947
`grub.cfg' files suitable for most cases. It is suitable for use when
948
upgrading a distribution, and will discover available kernels and
949
attempt to generate menu entries for them.
950
951
The file `/etc/default/grub' controls the operation of
952
`grub-mkconfig'. It is sourced by a shell script, and so must be valid
953
POSIX shell input; normally, it will just be a sequence of `KEY=value'
954
lines, but if the value contains spaces or other special characters
955
then it must be quoted. For example:
956
957
GRUB_TERMINAL_INPUT="console serial"
958
959
Valid keys in `/etc/default/grub' are as follows:
960
961
`GRUB_DEFAULT'
962
The default menu entry. This may be a number, in which case it
963
identifies the Nth entry in the generated menu counted from zero,
964
or the full name of a menu entry, or the special string `saved'.
965
Using the full name may be useful if you want to set a menu entry
966
as the default even though there may be a variable number of
967
entries before it.
968
969
If you set this to `saved', then the default menu entry will be
970
that saved by `GRUB_SAVEDEFAULT', `grub-set-default', or
971
`grub-reboot'.
972
973
The default is `0'.
974
975
`GRUB_SAVEDEFAULT'
976
If this option is set to `true', then, when an entry is selected,
977
save it as a new default entry for use by future runs of GRUB.
978
This is only useful if `GRUB_DEFAULT=saved'; it is a separate
979
option because `GRUB_DEFAULT=saved' is useful without this option,
980
in conjunction with `grub-set-default' or `grub-reboot'. Unset by
981
default. The remarks of *note Changes from GRUB Legacy:: on the
982
availability of `save_env' apply.
983
984
`GRUB_TIMEOUT'
985
Boot the default entry this many seconds after the menu is
986
displayed, unless a key is pressed. The default is `5'. Set to
987
`0' to boot immediately without displaying the menu, or to `-1' to
988
wait indefinitely.
989
990
`GRUB_HIDDEN_TIMEOUT'
991
Wait this many seconds for a key to be pressed before displaying
992
the menu. If no key is pressed during that time, boot
993
immediately. Unset by default.
994
995
`GRUB_HIDDEN_TIMEOUT_QUIET'
996
In conjunction with `GRUB_HIDDEN_TIMEOUT', set this to `true' to
997
suppress the verbose countdown while waiting for a key to be
998
pressed before displaying the menu. Unset by default.
999
1000
`GRUB_DEFAULT_BUTTON'
1001
`GRUB_TIMEOUT_BUTTON'
1002
`GRUB_HIDDEN_TIMEOUT_BUTTON'
1003
`GRUB_BUTTON_CMOS_ADDRESS'
1004
Variants of the corresponding variables without the `_BUTTON'
1005
suffix, used to support vendor-specific power buttons. *Note
1006
Vendor power-on keys::.
1007
1008
`GRUB_DISTRIBUTOR'
1009
Set by distributors of GRUB to their identifying name. This is
1010
used to generate more informative menu entry titles.
1011
1012
`GRUB_TERMINAL_INPUT'
1013
Select the terminal input device. You may select multiple devices
1014
here, separated by spaces.
1015
1016
Valid terminal input names depend on the platform, but may include
1017
`console' (PC BIOS and EFI consoles), `serial' (serial terminal),
1018
`ofconsole' (Open Firmware console), `at_keyboard' (PC AT
1019
keyboard, mainly useful with Coreboot), or `usb_keyboard' (USB
1020
keyboard using the HID Boot Protocol, for cases where the firmware
1021
does not handle this).
1022
1023
The default is to use the platform's native terminal input.
1024
1025
`GRUB_TERMINAL_OUTPUT'
1026
Select the terminal output device. You may select multiple
1027
devices here, separated by spaces.
1028
1029
Valid terminal output names depend on the platform, but may include
1030
`console' (PC BIOS and EFI consoles), `serial' (serial terminal),
1031
`gfxterm' (graphics-mode output), `ofconsole' (Open Firmware
1032
console), or `vga_text' (VGA text output, mainly useful with
1033
Coreboot).
1034
1035
The default is to use the platform's native terminal output.
1036
1037
`GRUB_TERMINAL'
1038
If this option is set, it overrides both `GRUB_TERMINAL_INPUT' and
1039
`GRUB_TERMINAL_OUTPUT' to the same value.
1040
1041
`GRUB_SERIAL_COMMAND'
1042
A command to configure the serial port when using the serial
1043
console. *Note serial::. Defaults to `serial'.
1044
1045
`GRUB_CMDLINE_LINUX'
1046
Command-line arguments to add to menu entries for the Linux kernel.
1047
1048
`GRUB_CMDLINE_LINUX_DEFAULT'
1049
Unless `GRUB_DISABLE_RECOVERY' is set to `true', two menu entries
1050
will be generated for each Linux kernel: one default entry and one
1051
entry for recovery mode. This option lists command-line arguments
1052
to add only to the default menu entry, after those listed in
1053
`GRUB_CMDLINE_LINUX'.
1054
1055
`GRUB_CMDLINE_NETBSD'
1056
`GRUB_CMDLINE_NETBSD_DEFAULT'
1057
As `GRUB_CMDLINE_LINUX' and `GRUB_CMDLINE_LINUX_DEFAULT', but for
1058
NetBSD.
1059
1060
`GRUB_CMDLINE_XEN'
1061
`GRUB_CMDLINE_XEN_DEFAULT'
1062
As `GRUB_CMDLINE_LINUX' and `GRUB_CMDLINE_LINUX_DEFAULT', but for
1063
Linux and Xen.
1064
1065
`GRUB_DISABLE_LINUX_UUID'
1066
Normally, `grub-mkconfig' will generate menu entries that use
1067
universally-unique identifiers (UUIDs) to identify the root
1068
filesystem to the Linux kernel, using a `root=UUID=...' kernel
1069
parameter. This is usually more reliable, but in some cases it
1070
may not be appropriate. To disable the use of UUIDs, set this
1071
option to `true'.
1072
1073
`GRUB_DISABLE_RECOVERY'
1074
If this option is set to `true', disable the generation of recovery
1075
mode menu entries.
1076
1077
`GRUB_VIDEO_BACKEND'
1078
If graphical video support is required, either because the
1079
`gfxterm' graphical terminal is in use or because
1080
`GRUB_GFXPAYLOAD_LINUX' is set, then `grub-mkconfig' will normally
1081
load all available GRUB video drivers and use the one most
1082
appropriate for your hardware. If you need to override this for
1083
some reason, then you can set this option.
1084
1085
After `grub-install' has been run, the available video drivers are
1086
listed in `/boot/grub/video.lst'.
1087
1088
`GRUB_GFXMODE'
1089
Set the resolution used on the `gfxterm' graphical terminal. Note
1090
that you can only use modes which your graphics card supports via
1091
VESA BIOS Extensions (VBE), so for example native LCD panel
1092
resolutions may not be available. The default is `640x480'.
1093
1094
`GRUB_BACKGROUND'
1095
Set a background image for use with the `gfxterm' graphical
1096
terminal. The value of this option must be a file readable by
1097
GRUB at boot time, and it must end with `.png', `.tga', `.jpg', or
1098
`.jpeg'. The image will be scaled if necessary to fit the screen.
1099
1100
`GRUB_THEME'
1101
Set a theme for use with the `gfxterm' graphical terminal.
1102
1103
`GRUB_GFXPAYLOAD_LINUX'
1104
Set to `text' to force the Linux kernel to boot in normal text
1105
mode, `keep' to preserve the graphics mode set using
1106
`GRUB_GFXMODE', `WIDTHxHEIGHT'[`xDEPTH'] to set a particular
1107
graphics mode, or a sequence of these separated by commas or
1108
semicolons to try several modes in sequence.
1109
1110
Depending on your kernel, your distribution, your graphics card,
1111
and the phase of the moon, note that using this option may cause
1112
GNU/Linux to suffer from various display problems, particularly
1113
during the early part of the boot sequence. If you have problems,
1114
set this option to `text' and GRUB will tell Linux to boot in
1115
normal text mode.
1116
1117
`GRUB_DISABLE_OS_PROBER'
1118
Normally, `grub-mkconfig' will try to use the external `os-prober'
1119
program, if installed, to discover other operating systems
1120
installed on the same system and generate appropriate menu entries
1121
for them. Set this option to `true' to disable this.
1122
1123
`GRUB_INIT_TUNE'
1124
Play a tune on the speaker when GRUB starts. This is particularly
1125
useful for users unable to see the screen. The value of this
1126
option is passed directly to *note play::.
1127
1128
`GRUB_BADRAM'
1129
If this option is set, GRUB will issue a *note badram:: command to
1130
filter out specified regions of RAM.
1131
1132
1133
For more detailed customisation of `grub-mkconfig''s output, you may
1134
edit the scripts in `/etc/grub.d' directly. `/etc/grub.d/40_custom' is
1135
particularly useful for adding entire custom menu entries; simply type
1136
the menu entries you want to add at the end of that file, making sure
1137
to leave at least the first two lines intact.
1138
1139
1140
File: grub.info, Node: Shell-like scripting, Next: Embedded configuration, Prev: Simple configuration, Up: Configuration
1141
1142
5.2 Writing full configuration files directly
1143
=============================================
1144
1145
`grub.cfg' is written in GRUB's built-in scripting language, which has
1146
a syntax quite similar to that of GNU Bash and other Bourne shell
1147
derivatives.
1148
1149
Words
1150
=====
1151
1152
A "word" is a sequence of characters considered as a single unit by
1153
GRUB. Words are separated by "metacharacters", which are the following
1154
plus space, tab, and newline:
1155
1156
{ } | & $ ; < >
1157
1158
Quoting may be used to include metacharacters in words; see below.
1159
1160
Reserved words
1161
==============
1162
1163
Reserved words have a special meaning to GRUB. The following words are
1164
recognised as reserved when unquoted and either the first word of a
1165
simple command or the third word of a `for' command:
1166
1167
! [[ ]] { }
1168
case do done elif else esac fi for function
1169
if in menuentry select then time until while
1170
1171
Not all of these reserved words have a useful purpose yet; some are
1172
reserved for future expansion.
1173
1174
Quoting
1175
=======
1176
1177
Quoting is used to remove the special meaning of certain characters or
1178
words. It can be used to treat metacharacters as part of a word, to
1179
prevent reserved words from being recognised as such, and to prevent
1180
variable expansion.
1181
1182
There are three quoting mechanisms: the escape character, single
1183
quotes, and double quotes.
1184
1185
A non-quoted backslash (\) is the "escape character". It preserves
1186
the literal value of the next character that follows, with the
1187
exception of newline.
1188
1189
Enclosing characters in single quotes preserves the literal value of
1190
each character within the quotes. A single quote may not occur between
1191
single quotes, even when preceded by a backslash.
1192
1193
Enclosing characters in double quotes preserves the literal value of
1194
all characters within the quotes, with the exception of `$' and `\'.
1195
The `$' character retains its special meaning within double quotes.
1196
The backslash retains its special meaning only when followed by one of
1197
the following characters: `$', `"', `\', or newline. A
1198
backslash-newline pair is treated as a line continuation (that is, it is
1199
removed from the input stream and effectively ignored(1) (*note
1200
Shell-like scripting-Footnote-1::)). A double quote may be quoted
1201
within double quotes by preceding it with a backslash.
1202
1203
Variable expansion
1204
==================
1205
1206
The `$' character introduces variable expansion. The variable name to
1207
be expanded may be enclosed in braces, which are optional but serve to
1208
protect the variable to be expanded from characters immediately
1209
following it which could be interpreted as part of the name.
1210
1211
Normal variable names begin with an alphabetic character, followed
1212
by zero or more alphanumeric characters.
1213
1214
Positional variable names consist of one or more digits. They
1215
represent parameters passed to function calls, with `$1' representing
1216
the first parameter, and so on.
1217
1218
The special variable name `?' expands to the exit status of the most
1219
recently executed command. When positional variable names are active,
1220
other special variable names `@', `*' and `#' are defined and they
1221
expand to all positional parameters with necessary quoting, positional
1222
parameters without any quoting, and positional parameter count
1223
respectively.
1224
1225
Comments
1226
========
1227
1228
A word beginning with `#' causes that word and all remaining characters
1229
on that line to be ignored.
1230
1231
Simple commands
1232
===============
1233
1234
A "simple command" is a sequence of words separated by spaces or tabs
1235
and terminated by a semicolon or a newline. The first word specifies
1236
the command to be executed. The remaining words are passed as
1237
arguments to the invoked command.
1238
1239
The return value of a simple command is its exit status. If the
1240
reserved word `!' precedes the command, then the return value is
1241
instead the logical negation of the command's exit status.
1242
1243
Compound commands
1244
=================
1245
1246
A "compound command" is one of the following:
1247
1248
for NAME in WORD ...; do LIST; done
1249
The list of words following `in' is expanded, generating a list of
1250
items. The variable NAME is set to each element of this list in
1251
turn, and LIST is executed each time. The return value is the
1252
exit status of the last command that executes. If the expansion
1253
of the items following `in' results in an empty list, no commands
1254
are executed, and the return status is 0.
1255
1256
if LIST; then LIST; [elif LIST; then LIST;] ... [else LIST;] fi
1257
The `if' LIST is executed. If its exit status is zero, the `then'
1258
LIST is executed. Otherwise, each `elif' LIST is executed in
1259
turn, and if its exit status is zero, the corresponding `then'
1260
LIST is executed and the command completes. Otherwise, the `else'
1261
LIST is executed, if present. The exit status is the exit status
1262
of the last command executed, or zero if no condition tested true.
1263
1264
while COND; do LIST; done
1265
until COND; do LIST; done
1266
The `while' command continuously executes the `do' LIST as long as
1267
the last command in COND returns an exit status of zero. The
1268
`until' command is identical to the `while' command, except that
1269
the test is negated; the `do' LIST is executed as long as the last
1270
command in COND returns a non-zero exit status. The exit status
1271
of the `while' and `until' commands is the exit status of the last
1272
`do' LIST command executed, or zero if none was executed.
1273
1274
function NAME { COMMAND; ... }
1275
This defines a function named NAME. The "body" of the function is
1276
the list of commands within braces, each of which must be
1277
terminated with a semicolon or a newline. This list of commands
1278
will be executed whenever NAME is specified as the name of a
1279
simple command. Function definitions do not affect the exit
1280
status in `$?'. When executed, the exit status of a function is
1281
the exit status of the last command executed in the body.
1282
1283
menuentry TITLE [`--class=class' ...] [`--users=users'] [`--hotkey=key'] { COMMAND; ... }
1284
*Note menuentry::.
1285
1286
Built-in Commands
1287
=================
1288
1289
Some built-in commands are also provided by GRUB script to help script
1290
writers perform actions that are otherwise not possible. For example,
1291
these include commands to jump out of a loop without fully completing
1292
it, etc.
1293
1294
break [`n']
1295
Exit from within a `for', `while', or `until' loop. If `n' is
1296
specified, break `n' levels. `n' must be greater than or equal to
1297
1. If `n' is greater than the number of enclosing loops, all
1298
enclosing loops are exited. The return value is 0 unless `n' is
1299
not greater than or equal to 1.
1300
1301
continue [`n']
1302
Resume the next iteration of the enclosing `for', `while' or
1303
`until' loop. If `n' is specified, resume at the `n'th enclosing
1304
loop. `n' must be greater than or equal to 1. If `n' is greater
1305
than the number of enclosing loops, the last enclosing loop (the
1306
"top-level" loop) is resumed. The return value is 0 unless `n' is
1307
not greater than or equal to 1.
1308
1309
return [`n']
1310
Causes a function to exit with the return value specified by `n'.
1311
If `n' is omitted, the return status is that of the last command
1312
executed in the function body. If used outside a function the
1313
return status is false.
1314
1315
shift [`n']
1316
The positional parameters from `n'+1 ... are renamed to `$1'....
1317
Parameters represented by the numbers `$#' down to `$#'-`n'+1 are
1318
unset. `n' must be a non-negative number less than or equal to
1319
`$#'. If `n' is 0, no parameters are changed. If `n' is not
1320
given, it is assumed to be 1. If `n' is greater than `$#', the
1321
positional parameters are not changed. The return status is
1322
greater than zero if `n' is greater than `$#' or less than zero;
1323
otherwise 0.
1324
1325
1326
1327
File: grub.info, Node: Shell-like scripting-Footnotes, Up: Shell-like scripting
1328
1329
(1) Currently a backslash-newline pair within a variable name is not
1330
handled properly, so use this feature with some care.
1331
1332
1333
File: grub.info, Node: Embedded configuration, Prev: Shell-like scripting, Up: Configuration
1334
1335
5.3 Embedding a configuration file into GRUB
1336
============================================
1337
1338
GRUB supports embedding a configuration file directly into the core
1339
image, so that it is loaded before entering normal mode. This is
1340
useful, for example, when it is not straightforward to find the real
1341
configuration file, or when you need to debug problems with loading
1342
that file. `grub-install' uses this feature when it is not using BIOS
1343
disk functions or when installing to a different disk from the one
1344
containing `/boot/grub', in which case it needs to use the `search'
1345
command (*note search::) to find `/boot/grub'.
1346
1347
To embed a configuration file, use the `-c' option to
1348
`grub-mkimage'. The file is copied into the core image, so it may
1349
reside anywhere on the file system, and may be removed after running
1350
`grub-mkimage'.
1351
1352
After the embedded configuration file (if any) is executed, GRUB
1353
will load the `normal' module, which will then read the real
1354
configuration file from `$prefix/grub.cfg'. By this point, the `root'
1355
variable will also have been set to the root device name. For example,
1356
`prefix' might be set to `(hd0,1)/boot/grub', and `root' might be set to
1357
`hd0,1'. Thus, in most cases, the embedded configuration file only
1358
needs to set the `prefix' and `root' variables, and then drop through
1359
to GRUB's normal processing. A typical example of this might look like
1360
this:
1361
1362
search.fs_uuid 01234567-89ab-cdef-0123-456789abcdef root
1363
set prefix=($root)/boot/grub
1364
1365
(The `search_fs_uuid' module must be included in the core image for
1366
this example to work.)
1367
1368
In more complex cases, it may be useful to read other configuration
1369
files directly from the embedded configuration file. This allows such
1370
things as reading files not called `grub.cfg', or reading files from a
1371
directory other than that where GRUB's loadable modules are installed.
1372
To do this, include the `configfile' and `normal' modules in the core
1373
image, and embed a configuration file that uses the `configfile'
1374
command to load another file. The following example of this also
1375
requires the `echo', `search_label', and `test' modules to be included
1376
in the core image:
1377
1378
search.fs_label grub root
1379
if [ -e /boot/grub/example/test1.cfg ]; then
1380
set prefix=($root)/boot/grub
1381
configfile /boot/grub/example/test1.cfg
1382
else
1383
if [ -e /boot/grub/example/test2.cfg ]; then
1384
set prefix=($root)/boot/grub
1385
configfile /boot/grub/example/test2.cfg
1386
else
1387
echo "Could not find an example configuration file!"
1388
fi
1389
fi
1390
1391
The embedded configuration file may not contain menu entries
1392
directly, but may only read them from elsewhere using `configfile'.
1393
1394
1395
File: grub.info, Node: Theme file format, Next: Network, Prev: Configuration, Up: Top
1396
1397
6 Theme file format
1398
*******************
1399
1400
6.1 Introduction
1401
================
1402
1403
The GRUB graphical menu supports themes that can customize the layout
1404
and appearance of the GRUB boot menu. The theme is configured through
1405
a plain text file that specifies the layout of the various GUI
1406
components (including the boot menu, timeout progress bar, and text
1407
messages) as well as the appearance using colors, fonts, and images.
1408
Example is available in docs/example_theme.txt
1409
1410
6.2 Theme Elements
1411
==================
1412
1413
6.2.1 Colors
1414
------------
1415
1416
Colors can be specified in several ways:
1417
1418
* HTML-style "#RRGGBB" or "#RGB" format, where *R*, *G*, and *B* are
1419
hexadecimal digits (e.g., "#8899FF")
1420
1421
* as comma-separated decimal RGB values (e.g., "128, 128, 255")
1422
1423
* with "SVG 1.0 color names" (e.g., "cornflowerblue") which must be
1424
specified in lowercase.
1425
1426
6.2.2 Fonts
1427
-----------
1428
1429
The fonts GRUB uses "PFF2 font format" bitmap fonts. Fonts are
1430
specified with full font names. Currently there is no provision for a
1431
preference list of fonts, or deriving one font from another. Fonts are
1432
loaded with the "loadfont" command in GRUB. To see the list of loaded
1433
fonts, execute the "lsfonts" command. If there are too many fonts to
1434
fit on screen, do "set pager=1" before executing "lsfonts".
1435
1436
6.2.3 Progress Bar
1437
------------------
1438
1439
Figure 6.1
1440
1441
Figure 6.2
1442
1443
Progress bars are used to display the remaining time before GRUB
1444
boots the default menu entry. To create a progress bar that will
1445
display the remaining time before automatic boot, simply create a
1446
"progress_bar" component with the id "__timeout__". This indicates to
1447
GRUB that the progress bar should be updated as time passes, and it
1448
should be made invisible if the countdown to automatic boot is
1449
interrupted by the user.
1450
1451
Progress bars may optionally have text displayed on them. This is
1452
controlled through the "show_text" property, which can be set to either
1453
"true" or "false" to control whether text is displayed. When GRUB is
1454
counting down to automatic boot, the text informs the user of the
1455
number of seconds remaining.
1456
1457
6.2.4 Circular Progress Indicator
1458
---------------------------------
1459
1460
The circular progress indicator functions similarly to the progress
1461
bar. When given an id of "__timeout__", GRUB updates the circular
1462
progress indicator's value to indicate the time remaining. For the
1463
circular progress indicator, there are two images used to render it:
1464
the *center* image, and the *tick* image. The center image is rendered
1465
in the center of the component, while the tick image is used to render
1466
each mark along the circumference of the indicator.
1467
1468
6.2.5 Labels
1469
------------
1470
1471
Text labels can be placed on the boot screen. The font, color, and
1472
horizontal alignment can be specified for labels. If a label is given
1473
the id "__timeout__", then the "text" property for that label is also
1474
updated with a message informing the user of the number of seconds
1475
remaining until automatic boot. This is useful in case you want the
1476
text displayed somewhere else instead of directly on the progress bar.
1477
1478
6.2.6 Boot Menu
1479
---------------
1480
1481
The boot menu where GRUB displays the menu entries from the "grub.cfg"
1482
file. It is a list of items, where each item has a title and an
1483
optional icon. The icon is selected based on the *classes* specified
1484
for the menu entry. If there is a PNG file named "myclass.png" in the
1485
"grub/themes/icons" directory, it will be displayed for items which
1486
have the class *myclass*. The boot menu can be customized in several
1487
ways, such as the font and color used for the menu entry title, and by
1488
specifying styled boxes for the menu itself and for the selected item
1489
highlight.
1490
1491
6.2.7 Styled Boxes
1492
------------------
1493
1494
One of the most important features for customizing the layout is the
1495
use of *styled boxes*. A styled box is composed of 9 rectangular (and
1496
potentially empty) regions, which are used to seamlessly draw the
1497
styled box on screen:
1498
1499
Northwest (nw) North (n) Northeast (ne)
1500
West (w) Center (c) East (e)
1501
Southwest (sw) South (s) Southeast (se)
1502
1503
To support any size of box on screen, the center slice and the
1504
slices for the top, bottom, and sides are all scaled to the correct
1505
size for the component on screen, using the following rules:
1506
1507
1. The edge slices (north, south, east, and west) are scaled in the
1508
direction of the edge they are adjacent to. For instance, the
1509
west slice is scaled vertically.
1510
1511
2. The corner slices (northwest, northeast, southeast, and southwest)
1512
are not scaled.
1513
1514
3. The center slice is scaled to fill the remaining space in the
1515
middle.
1516
1517
As an example of how an image might be sliced up, consider the
1518
styled box used for a terminal view.
1519
1520
Figure 6.3
1521
1522
6.2.8 Creating Styled Box Images
1523
--------------------------------
1524
1525
The Inkscape_ scalable vector graphics editor is a very useful tool for
1526
creating styled box images. One process that works well for slicing a
1527
drawing into the necessary image slices is:
1528
1529
1. Create or open the drawing you'd like use.
1530
1531
2. Create a new layer on the top of the layer stack. Make it
1532
visible. Select this layer as the current layer.
1533
1534
3. Draw 9 rectangles on your drawing where you'd like the slices to
1535
be. Clear the fill option, and set the stroke to 1 pixel wide
1536
solid stroke. The corners of the slices must meet precisely; if
1537
it is off by a single pixel, it will probably be evident when the
1538
styled box is rendered in the GRUB menu. You should probably go
1539
to File | Document Properties | Grids and enable a grid or create
1540
a guide (click on one of the rulers next to the drawing and drag
1541
over the drawing; release the mouse button to place the guide) to
1542
help place the rectangles precisely.
1543
1544
4. Right click on the center slice rectangle and choose Object
1545
Properties. Change the "Id" to "slice_c" and click Set. Repeat
1546
this for the remaining 8 rectangles, giving them Id values of
1547
"slice_n", "slice_ne", "slice_e", and so on according to the
1548
location.
1549
1550
5. Save the drawing.
1551
1552
6. Select all the slice rectangles. With the slice layer selected,
1553
you can simply press Ctrl+A to select all rectangles. The status
1554
bar should indicate that 9 rectangles are selected.
1555
1556
7. Click the layer hide icon for the slice layer in the layer
1557
palette. The rectangles will remain selected, even though they
1558
are hidden.
1559
1560
8. Choose File | Export Bitmap and check the *Batch export 9 selected
1561
objects* box. Make sure that *Hide all except selected* is
1562
unchecked. click *Export*. This will create PNG files in the same
1563
directory as the drawing, named after the slices. These can now
1564
be used for a styled box in a GRUB theme.
1565
1566
6.3 Theme File Manual
1567
=====================
1568
1569
The theme file is a plain text file. Lines that begin with "#" are
1570
ignored and considered comments. (Note: This may not be the case if
1571
the previous line ended where a value was expected.)
1572
1573
The theme file contains two types of statements:
1574
1. Global properties.
1575
1576
2. Component construction.
1577
1578
6.3.1 Global Properties
1579
-----------------------
1580
1581
6.3.2 Format
1582
------------
1583
1584
Global properties are specified with the simple format:
1585
* name1: value1
1586
1587
* name2: "value which may contain spaces"
1588
1589
* name3: #88F
1590
1591
In this example, name3 is assigned a color value.
1592
1593
6.3.3 Global Property List
1594
--------------------------
1595
1596
title-text Specifies the text to display at the top
1597
center of the screen as a title.
1598
title-font Defines the font used for the title
1599
message at the top of the screen.
1600
title-color Defines the color of the title message.
1601
message-font Defines the font used for messages, such
1602
as when GRUB is unable to automatically
1603
boot an entry.
1604
message-color Defines the color of the message text.
1605
message-bg-color Defines the background color of the
1606
message text area.
1607
desktop-image Specifies the image to use as the
1608
background. It will be scaled to fit the
1609
screen size.
1610
desktop-color Specifies the color for the background if
1611
*desktop-image* is not specified.
1612
terminal-box Specifies the file name pattern for the
1613
styled box slices used for the command
1614
line terminal window. For example,
1615
"terminal-box: terminal_*.png" will use
1616
the images "terminal_c.png" as the center
1617
area, "terminal_n.png" as the north (top)
1618
edge, "terminal_nw.png" as the northwest
1619
(upper left) corner, and so on. If the
1620
image for any slice is not found, it will
1621
simply be left empty.
1622
1623
6.3.4 Component Construction
1624
----------------------------
1625
1626
Greater customizability comes is provided by components. A tree of
1627
components forms the user interface. *Containers* are components that
1628
can contain other components, and there is always a single root
1629
component which is an instance of a *canvas* container.
1630
1631
Components are created in the theme file by prefixing the type of
1632
component with a '+' sign:
1633
1634
` + label { text="GRUB" font="aqui 11" color="#8FF" } '
1635
1636
properties of a component are specified as "name = value" (whitespace
1637
surrounding tokens is optional and is ignored) where *value* may be:
1638
* a single word (e.g., "align = center", "color = #FF8080"),
1639
1640
* a quoted string (e.g., "text = "Hello, World!""), or
1641
1642
* a tuple (e.g., "preferred_size = (120, 80)").
1643
1644
6.3.5 Component List
1645
--------------------
1646
1647
The following is a list of the components and the properties they
1648
support.
1649
1650
* label A label displays a line of text.
1651
1652
Properties:
1653
text The text to display.
1654
font The font to use for text display.
1655
color The color of the text.
1656
align The horizontal alignment of the text within
1657
the component. Options are "left", "center",
1658
and "right".
1659
1660
* image A component that displays an image. The image is scaled
1661
to fit the component, although the preferred size defaults to
1662
the image's original size unless the "preferred_size" property
1663
is explicitly set.
1664
1665
Properties:
1666
1667
file The full path to the image file to load.
1668
1669
* progress_bar Displays a horizontally oriented progress bar. It
1670
can be rendered using simple solid filled rectangles, or using
1671
a pair of pixmap styled boxes.
1672
1673
Properties:
1674
1675
fg_color The foreground color for plain solid color
1676
rendering.
1677
bg_color The background color for plain solid color
1678
rendering.
1679
border_color The border color for plain solid color
1680
rendering.
1681
text_color The text color.
1682
show_text Boolean value indicating whether or not text
1683
should be displayed on the progress bar. If
1684
set to *false*, then no text will be displayed
1685
on the bar. If set to any other value, text
1686
will be displayed on the bar.
1687
bar_style The styled box specification for the frame of
1688
the progress bar. Example:
1689
"progress_frame_*.png"
1690
highlight_styleThe styled box specification for the
1691
highlighted region of the progress bar. This
1692
box will be used to paint just the highlighted
1693
region of the bar, and will be increased in
1694
size as the bar nears completion. Example:
1695
"progress_hl_*.png".
1696
text The text to display on the progress bar. If
1697
the progress bar's ID is set to "__timeout__",
1698
then GRUB will updated this property with an
1699
informative message as the timeout approaches.
1700
value The progress bar current value. Normally not
1701
set manually.
1702
start The progress bar start value. Normally not
1703
set manually.
1704
end The progress bar end value. Normally not set
1705
manually.
1706
1707
* circular_progress Displays a circular progress indicator. The
1708
appearance of this component is determined by two images: the
1709
*center* image and the *tick* image. The center image is
1710
generally larger and will be drawn in the center of the
1711
component. Around the circumference of a circle within the
1712
component, the tick image will be drawn a certain number of
1713
times, depending on the properties of the component.
1714
1715
Properties:
1716
1717
center_bitmap The file name of the image to draw in
1718
the center of the component.
1719
tick_bitmap The file name of the image to draw for
1720
the tick marks.
1721
num_ticks The number of ticks that make up a full
1722
circle.
1723
ticks_disappear Boolean value indicating whether tick
1724
marks should progressively appear,
1725
or progressively disappear as *value*
1726
approaches *end*. Specify "true"
1727
or "false".
1728
value The progress indicator current value.
1729
Normally not set manually.
1730
start The progress indicator start value.
1731
Normally not set manually.
1732
end The progress indicator end value.
1733
Normally not set manually.
1734
1735
* boot_menu Displays the GRUB boot menu. It allows selecting
1736
items and executing them.
1737
1738
Properties:
1739
1740
item_font The font to use for the menu item
1741
titles.
1742
selected_item_font The font to use for the selected
1743
menu item, or "inherit" (the
1744
default) to use "item_font"
1745
for the selected menu item as
1746
well.
1747
item_color The color to use for the menu
1748
item titles.
1749
selected_item_color The color to use for the selected
1750
menu item, or "inherit" (the
1751
default) to use
1752
"item_color" for the selected
1753
menu item as well.
1754
icon_width The width of menu item icons.
1755
Icons are scaled to the specified
1756
size.
1757
icon_height The height of menu item icons.
1758
item_height The height of each menu item in
1759
pixels.
1760
item_padding The amount of space in pixels to
1761
leave on each side of the menu
1762
item contents.
1763
item_icon_space The space between an item's icon
1764
and the title text, in pixels.
1765
item_spacing The amount of space to leave
1766
between menu items, in pixels.
1767
menu_pixmap_style The image file pattern for the
1768
menu frame styled box.
1769
Example: "menu_*.png" (this will
1770
use images such as "menu_c.png",
1771
"menu_w.png", `menu_nw.png",
1772
etc.)
1773
selected_item_pixmap_style The image file pattern for the
1774
selected item highlight styled
1775
box.
1776
scrollbar Boolean value indicating whether
1777
the scroll bar should be drawn if
1778
the frame and thumb styled
1779
boxes are configured.
1780
scrollbar_frame The image file pattern for the
1781
entire scroll bar.
1782
Example: "scrollbar_*.png"
1783
scrollbar_thumb The image file pattern for the
1784
scroll bar thumb (the part of the
1785
scroll bar that moves as
1786
scrolling occurs).
1787
Example: "scrollbar_thumb_*.png"
1788
max_items_shown The maximum number of items to
1789
show on the menu. If there are
1790
more than *max_items_shown*
1791
items in the menu, the list will
1792
scroll to make all items
1793
accessible.
1794
1795
* canvas Canvas is a container that allows manual placement of
1796
components within it. It does not alter the positions of its
1797
child components. It assigns all child components their
1798
preferred sizes.
1799
1800
* hbox The *hbox* container lays out its children from left to
1801
right, giving each one its preferred width. The height of each
1802
child is set to the maximum of the preferred heights of all
1803
children.
1804
1805
* vbox The *vbox* container lays out its children from top to
1806
bottom, giving each one its preferred height. The width of
1807
each child is set to the maximum of the preferred widths of all
1808
children.
1809
1810
6.3.6 Common properties
1811
-----------------------
1812
1813
The following properties are supported by all components:
1814
`left'
1815
The distance from the left border of container to left border of
1816
the object in either of three formats:
1817
x Value in pixels
1818
p% Percentage
1819
p%+x mixture of both
1820
1821
`top'
1822
The distance from the left border of container to left border of
1823
the object in same format.
1824
1825
`width'
1826
The width of object in same format.
1827
1828
`height'
1829
The height of object in same format.
1830
1831
`id'
1832
The identifier for the component. This can be any arbitrary
1833
string. The ID can be used by scripts to refer to various
1834
components in the GUI component tree. Currently, there is one
1835
special ID value that GRUB recognizes:
1836
1837
"__timeout__" Any component with this ID will have its
1838
*text*, *start*, *end*, *value*, and *visible*
1839
properties set by GRUB when it is counting
1840
down to an automatic boot of the default menu
1841
entry.
1842
1843
1844
File: grub.info, Node: Network, Next: Serial terminal, Prev: Theme file format, Up: Top
1845
1846
7 Booting GRUB from the network
1847
*******************************
1848
1849
The following instructions only work on PC BIOS systems where the
1850
Preboot eXecution Environment (PXE) is available.
1851
1852
To generate a PXE boot image, run:
1853
1854
grub-mkimage --format=i386-pc-pxe --output=grub.pxe --prefix='(pxe)/boot/grub' pxe pxecmd
1855
1856
Copy `grub.pxe', `/boot/grub/*.mod', and `/boot/grub/*.lst' to the
1857
PXE (TFTP) server, ensuring that `*.mod' and `*.lst' are accessible via
1858
the `/boot/grub/' path from the TFTP server root. Set the DHCP server
1859
configuration to offer `grub.pxe' as the boot file (the `filename'
1860
option in ISC dhcpd).
1861
1862
You can also use the `grub-mknetdir' utility to generate an image
1863
and a GRUB directory tree, rather than copying files around manually.
1864
1865
After GRUB has started, files on the TFTP server will be accessible
1866
via the `(pxe)' device.
1867
1868
The server and gateway IP address can be controlled by changing the
1869
`(pxe)' device name to `(pxe:SERVER-IP)' or
1870
`(pxe:SERVER-IP:GATEWAY-IP)'. Note that this should be changed both in
1871
the prefix and in any references to the device name in the
1872
configuration file.
1873
1874
GRUB provides several environment variables which may be used to
1875
inspect or change the behaviour of the PXE device:
1876
1877
`net_pxe_ip'
1878
The IP address of this machine. Read-only.
1879
1880
`net_pxe_mac'
1881
The network interface's MAC address. Read-only.
1882
1883
`net_pxe_hostname'
1884
The client host name provided by DHCP. Read-only.
1885
1886
`net_pxe_domain'
1887
The client domain name provided by DHCP. Read-only.
1888
1889
`net_pxe_rootpath'
1890
The path to the client's root disk provided by DHCP. Read-only.
1891
1892
`net_pxe_extensionspath'
1893
The path to additional DHCP vendor extensions provided by DHCP.
1894
Read-only.
1895
1896
`net_pxe_boot_file'
1897
The boot file name provided by DHCP. Read-only.
1898
1899
`net_pxe_dhcp_server_name'
1900
The name of the DHCP server responsible for these boot parameters.
1901
Read-only.
1902
1903
`pxe_blksize'
1904
The PXE transfer block size. Read-write, defaults to 512.
1905
1906
`pxe_default_server'
1907
The default PXE server. Read-write, although setting this is only
1908
useful before opening a PXE device.
1909
1910
`pxe_default_gateway'
1911
The default gateway to use when contacting the PXE server.
1912
Read-write, although setting this is only useful before opening a
1913
PXE device.
1914
1915
1916
File: grub.info, Node: Serial terminal, Next: Vendor power-on keys, Prev: Network, Up: Top
1917
1918
8 Using GRUB via a serial line
1919
******************************
1920
1921
This chapter describes how to use the serial terminal support in GRUB.
1922
1923
If you have many computers or computers with no display/keyboard, it
1924
could be very useful to control the computers through serial
1925
communications. To connect one computer with another via a serial line,
1926
you need to prepare a null-modem (cross) serial cable, and you may need
1927
to have multiport serial boards, if your computer doesn't have extra
1928
serial ports. In addition, a terminal emulator is also required, such as
1929
minicom. Refer to a manual of your operating system, for more
1930
information.
1931
1932
As for GRUB, the instruction to set up a serial terminal is quite
1933
simple. Here is an example:
1934
1935
grub> serial --unit=0 --speed=9600
1936
grub> terminal_input serial; terminal_output serial
1937
1938
The command `serial' initializes the serial unit 0 with the speed
1939
9600bps. The serial unit 0 is usually called `COM1', so, if you want to
1940
use COM2, you must specify `--unit=1' instead. This command accepts
1941
many other options, so please refer to *note serial::, for more details.
1942
1943
The commands `terminal_input' (*note terminal_input::) and
1944
`terminal_output' (*note terminal_output::) choose which type of
1945
terminal you want to use. In the case above, the terminal will be a
1946
serial terminal, but you can also pass `console' to the command, as
1947
`terminal serial console'. In this case, a terminal in which you press
1948
any key will be selected as a GRUB terminal. In the example above, note
1949
that you need to put both commands on the same command line, as you
1950
will lose the ability to type commands on the console after the first
1951
command.
1952
1953
However, note that GRUB assumes that your terminal emulator is
1954
compatible with VT100 by default. This is true for most terminal
1955
emulators nowadays, but you should pass the option `--dumb' to the
1956
command if your terminal emulator is not VT100-compatible or implements
1957
few VT100 escape sequences. If you specify this option then GRUB
1958
provides you with an alternative menu interface, because the normal
1959
menu requires several fancy features of your terminal.
1960
1961
1962
File: grub.info, Node: Vendor power-on keys, Next: Images, Prev: Serial terminal, Up: Top
1963
1964
9 Using GRUB with vendor power-on keys
1965
**************************************
1966
1967
Some laptop vendors provide an additional power-on button which boots
1968
another OS. GRUB supports such buttons with the `GRUB_TIMEOUT_BUTTON',
1969
`GRUB_DEFAULT_BUTTON', `GRUB_HIDDEN_TIMEOUT_BUTTON' and
1970
`GRUB_BUTTON_CMOS_ADDRESS' variables in default/grub (*note Simple
1971
configuration::). `GRUB_TIMEOUT_BUTTON', `GRUB_DEFAULT_BUTTON' and
1972
`GRUB_HIDDEN_TIMEOUT_BUTTON' are used instead of the corresponding
1973
variables without the `_BUTTON' suffix when powered on using the special
1974
button. `GRUB_BUTTON_CMOS_ADDRESS' is vendor-specific and partially
1975
model-specific. Values known to the GRUB team are:
1976
1977
<Dell XPS M1530>
1978
85:3
1979
1980
<Asus EeePC 1005PE>
1981
84:1 (unconfirmed)
1982
1983
To take full advantage of this function, install GRUB into the MBR
1984
(*note Installing GRUB using grub-install::).
1985
1986
1987
File: grub.info, Node: Images, Next: Filesystem, Prev: Vendor power-on keys, Up: Top
1988
1989
10 GRUB image files
1990
*******************
1991
1992
GRUB consists of several images: a variety of bootstrap images for
1993
starting GRUB in various ways, a kernel image, and a set of modules
1994
which are combined with the kernel image to form a core image. Here is
1995
a short overview of them.
1996
1997
`boot.img'
1998
On PC BIOS systems, this image is the first part of GRUB to start.
1999
It is written to a master boot record (MBR) or to the boot sector
2000
of a partition. Because a PC boot sector is 512 bytes, the size
2001
of this image is exactly 512 bytes.
2002
2003
The sole function of `boot.img' is to read the first sector of the
2004
core image from a local disk and jump to it. Because of the size
2005
restriction, `boot.img' cannot understand any file system
2006
structure, so `grub-setup' hardcodes the location of the first
2007
sector of the core image into `boot.img' when installing GRUB.
2008
2009
`diskboot.img'
2010
This image is used as the first sector of the core image when
2011
booting from a hard disk. It reads the rest of the core image
2012
into memory and starts the kernel. Since file system handling is
2013
not yet available, it encodes the location of the core image using
2014
a block list format.
2015
2016
`cdboot.img'
2017
This image is used as the first sector of the core image when
2018
booting from a CD-ROM drive. It performs a similar function to
2019
`diskboot.img'.
2020
2021
`pxeboot.img'
2022
This image is used as the start of the core image when booting
2023
from the network using PXE. *Note Network::.
2024
2025
`lnxboot.img'
2026
This image may be placed at the start of the core image in order
2027
to make GRUB look enough like a Linux kernel that it can be booted
2028
by LILO using an `image=' section.
2029
2030
`kernel.img'
2031
This image contains GRUB's basic run-time facilities: frameworks
2032
for device and file handling, environment variables, the rescue
2033
mode command-line parser, and so on. It is rarely used directly,
2034
but is built into all core images.
2035
2036
`core.img'
2037
This is the core image of GRUB. It is built dynamically from the
2038
kernel image and an arbitrary list of modules by the `grub-mkimage'
2039
program. Usually, it contains enough modules to access
2040
`/boot/grub', and loads everything else (including menu handling,
2041
the ability to load target operating systems, and so on) from the
2042
file system at run-time. The modular design allows the core image
2043
to be kept small, since the areas of disk where it must be
2044
installed are often as small as 32KB.
2045
2046
On PC systems using the traditional MBR partition table format,
2047
the core image is usually installed in the "MBR gap" between the
2048
master boot record and the first partition, or sometimes it is
2049
installed in a file system and read directly from that. The
2050
latter is not recommended because GRUB needs to encode the
2051
location of all the core image sectors in `diskboot.img', and if
2052
the file system ever moves the core image around (as it is entitled
2053
to do) then GRUB must be reinstalled; it also means that GRUB will
2054
not be able to reliably find the core image if it resides on a
2055
different disk than the one to which `boot.img' was installed.
2056
2057
On PC systems using the more recent GUID Partition Table (GPT)
2058
format, the core image should be installed to a BIOS Boot
2059
Partition. This may be created by GNU Parted using a command such
2060
as the following:
2061
2062
# parted /dev/DISK set PARTITION-NUMBER bios_grub on
2063
2064
*Caution:* Be very careful which partition you select! When GRUB
2065
finds a BIOS Boot Partition during installation, it will
2066
automatically overwrite part of it. Make sure that the partition
2067
does not contain any other data.
2068
2069
`*.mod'
2070
Everything else in GRUB resides in dynamically loadable modules.
2071
These are often loaded automatically, or built into the core image
2072
if they are essential, but may also be loaded manually using the
2073
`insmod' command (*note insmod::).
2074
2075
For GRUB Legacy users
2076
=====================
2077
2078
GRUB 2 has a different design from GRUB Legacy, and so correspondences
2079
with the images it used cannot be exact. Nevertheless, GRUB Legacy
2080
users often ask questions in the terms they are familiar with, and so
2081
here is a brief guide to how GRUB 2's images relate to that.
2082
2083
`stage1'
2084
Stage 1 from GRUB Legacy was very similar to `boot.img' in GRUB 2,
2085
and they serve the same function.
2086
2087
`*_stage1_5'
2088
In GRUB Legacy, Stage 1.5's function was to include enough
2089
filesystem code to allow the much larger Stage 2 to be read from
2090
an ordinary filesystem. In this respect, its function was similar
2091
to `core.img' in GRUB 2. However, `core.img' is much more capable
2092
than Stage 1.5 was; since it offers a rescue shell, it is
2093
sometimes possible to recover manually in the event that it is
2094
unable to load any other modules, for example if partition numbers
2095
have changed. `core.img' is built in a more flexible way,
2096
allowing GRUB 2 to support reading modules from advanced disk
2097
types such as LVM and RAID.
2098
2099
GRUB Legacy could run with only Stage 1 and Stage 2 in some limited
2100
configurations, while GRUB 2 requires `core.img' and cannot work
2101
without it.
2102
2103
`stage2'
2104
GRUB 2 has no single Stage 2 image. Instead, it loads modules from
2105
`/boot/grub' at run-time.
2106
2107
`stage2_eltorito'
2108
In GRUB 2, images for booting from CD-ROM drives are now
2109
constructed using `cdboot.img' and `core.img', making sure that
2110
the core image contains the `iso9660' module. It is usually best
2111
to use the `grub-mkrescue' program for this.
2112
2113
`nbgrub'
2114
There is as yet no equivalent for `nbgrub' in GRUB 2; it was used
2115
by Etherboot and some other network boot loaders.
2116
2117
`pxegrub'
2118
In GRUB 2, images for PXE network booting are now constructed using
2119
`pxeboot.img' and `core.img', making sure that the core image
2120
contains the `pxe' and `pxecmd' modules. *Note Network::.
2121
2122
2123
File: grub.info, Node: Filesystem, Next: Interface, Prev: Images, Up: Top
2124
2125
11 Filesystem syntax and semantics
2126
**********************************
2127
2128
GRUB uses a special syntax for specifying disk drives which can be
2129
accessed by BIOS. Because of BIOS limitations, GRUB cannot distinguish
2130
between IDE, ESDI, SCSI, or others. You must know yourself which BIOS
2131
device is equivalent to which OS device. Normally, that will be clear if
2132
you see the files in a device or use the command `search' (*note
2133
search::).
2134
2135
* Menu:
2136
2137
* Device syntax:: How to specify devices
2138
* File name syntax:: How to specify files
2139
* Block list syntax:: How to specify block lists
2140
2141
2142
File: grub.info, Node: Device syntax, Next: File name syntax, Up: Filesystem
2143
2144
11.1 How to specify devices
2145
===========================
2146
2147
The device syntax is like this:
2148
2149
`(DEVICE[,PART-NUM][,BSD-SUBPART-LETTER])'
2150
2151
`[]' means the parameter is optional. DEVICE should be either `fd'
2152
or `hd' followed by a digit, like `fd0'. But you can also set DEVICE
2153
to a hexadecimal or a decimal number which is a BIOS drive number, so
2154
the following are equivalent:
2155
2156
(hd0)
2157
(0x80)
2158
(128)
2159
2160
PART-NUM represents the partition number of DEVICE, starting from
2161
one for primary partitions and from five for extended partitions, and
2162
BSD-SUBPART-LETTER represents the BSD disklabel subpartition, such as
2163
`a' or `e'.
2164
2165
A shortcut for specifying BSD subpartitions is
2166
`(DEVICE,BSD-SUBPART-LETTER)', in this case, GRUB searches for the
2167
first PC partition containing a BSD disklabel, then finds the
2168
subpartition BSD-SUBPART-LETTER. Here is an example:
2169
2170
(hd0,a)
2171
2172
The syntax `(hd0)' represents using the entire disk (or the MBR when
2173
installing GRUB), while the syntax `(hd0,1)' represents using the first
2174
partition of the disk (or the boot sector of the partition when
2175
installing GRUB).
2176
2177
If you enabled the network support, the special drive `(pxe)' is
2178
also available. Before using the network drive, you must initialize the
2179
network. *Note Network::, for more information.
2180
2181
If you boot GRUB from a CD-ROM, `(cd)' is available. *Note Making a
2182
GRUB bootable CD-ROM::, for details.
2183
2184
2185
File: grub.info, Node: File name syntax, Next: Block list syntax, Prev: Device syntax, Up: Filesystem
2186
2187
11.2 How to specify files
2188
=========================
2189
2190
There are two ways to specify files, by "absolute file name" and by
2191
"block list".
2192
2193
An absolute file name resembles a Unix absolute file name, using `/'
2194
for the directory separator (not `\' as in DOS). One example is
2195
`(hd0,1)/boot/grub/grub.cfg'. This means the file `/boot/grub/grub.cfg'
2196
in the first partition of the first hard disk. If you omit the device
2197
name in an absolute file name, GRUB uses GRUB's "root device"
2198
implicitly. So if you set the root device to, say, `(hd1,1)' by the
2199
command `set root=(hd1,1)' (*note set::), then `/boot/kernel' is the
2200
same as `(hd1,1)/boot/kernel'.
2201
2202
2203
File: grub.info, Node: Block list syntax, Prev: File name syntax, Up: Filesystem
2204
2205
11.3 How to specify block lists
2206
===============================
2207
2208
A block list is used for specifying a file that doesn't appear in the
2209
filesystem, like a chainloader. The syntax is
2210
`[OFFSET]+LENGTH[,[OFFSET]+LENGTH]...'. Here is an example:
2211
2212
`0+100,200+1,300+300'
2213
2214
This represents that GRUB should read blocks 0 through 99, block 200,
2215
and blocks 300 through 599. If you omit an offset, then GRUB assumes
2216
the offset is zero.
2217
2218
Like the file name syntax (*note File name syntax::), if a blocklist
2219
does not contain a device name, then GRUB uses GRUB's "root device". So
2220
`(hd0,2)+1' is the same as `+1' when the root device is `(hd0,2)'.
2221
2222
2223
File: grub.info, Node: Interface, Next: Commands, Prev: Filesystem, Up: Top
2224
2225
12 GRUB's user interface
2226
************************
2227
2228
GRUB has both a simple menu interface for choosing preset entries from a
2229
configuration file, and a highly flexible command-line for performing
2230
any desired combination of boot commands.
2231
2232
GRUB looks for its configuration file as soon as it is loaded. If one
2233
is found, then the full menu interface is activated using whatever
2234
entries were found in the file. If you choose the "command-line" menu
2235
option, or if the configuration file was not found, then GRUB drops to
2236
the command-line interface.
2237
2238
* Menu:
2239
2240
* Command-line interface:: The flexible command-line interface
2241
* Menu interface:: The simple menu interface
2242
* Menu entry editor:: Editing a menu entry
2243
2244
2245
File: grub.info, Node: Command-line interface, Next: Menu interface, Up: Interface
2246
2247
12.1 The flexible command-line interface
2248
========================================
2249
2250
The command-line interface provides a prompt and after it an editable
2251
text area much like a command-line in Unix or DOS. Each command is
2252
immediately executed after it is entered(1) (*note Command-line
2253
interface-Footnote-1::). The commands (*note Command-line and menu
2254
entry commands::) are a subset of those available in the configuration
2255
file, used with exactly the same syntax.
2256
2257
Cursor movement and editing of the text on the line can be done via a
2258
subset of the functions available in the Bash shell:
2259
2260
<C-f>
2261
<PC right key>
2262
Move forward one character.
2263
2264
<C-b>
2265
<PC left key>
2266
Move back one character.
2267
2268
<C-a>
2269
<HOME>
2270
Move to the start of the line.
2271
2272
<C-e>
2273
<END>
2274
Move the the end of the line.
2275
2276
<C-d>
2277
<DEL>
2278
Delete the character underneath the cursor.
2279
2280
<C-h>
2281
<BS>
2282
Delete the character to the left of the cursor.
2283
2284
<C-k>
2285
Kill the text from the current cursor position to the end of the
2286
line.
2287
2288
<C-u>
2289
Kill backward from the cursor to the beginning of the line.
2290
2291
<C-y>
2292
Yank the killed text back into the buffer at the cursor.
2293
2294
<C-p>
2295
<PC up key>
2296
Move up through the history list.
2297
2298
<C-n>
2299
<PC down key>
2300
Move down through the history list.
2301
2302
When typing commands interactively, if the cursor is within or before
2303
the first word in the command-line, pressing the <TAB> key (or <C-i>)
2304
will display a listing of the available commands, and if the cursor is
2305
after the first word, the `<TAB>' will provide a completion listing of
2306
disks, partitions, and file names depending on the context. Note that
2307
to obtain a list of drives, one must open a parenthesis, as `root ('.
2308
2309
Note that you cannot use the completion functionality in the TFTP
2310
filesystem. This is because TFTP doesn't support file name listing for
2311
the security.
2312
2313
2314
File: grub.info, Node: Command-line interface-Footnotes, Up: Command-line interface
2315
2316
(1) However, this behavior will be changed in the future version, in
2317
a user-invisible way.
2318
2319
2320
File: grub.info, Node: Menu interface, Next: Menu entry editor, Prev: Command-line interface, Up: Interface
2321
2322
12.2 The simple menu interface
2323
==============================
2324
2325
The menu interface is quite easy to use. Its commands are both
2326
reasonably intuitive and described on screen.
2327
2328
Basically, the menu interface provides a list of "boot entries" to
2329
the user to choose from. Use the arrow keys to select the entry of
2330
choice, then press <RET> to run it. An optional timeout is available
2331
to boot the default entry (the first one if not set), which is aborted
2332
by pressing any key.
2333
2334
Commands are available to enter a bare command-line by pressing <c>
2335
(which operates exactly like the non-config-file version of GRUB, but
2336
allows one to return to the menu if desired by pressing <ESC>) or to
2337
edit any of the "boot entries" by pressing <e>.
2338
2339
If you protect the menu interface with a password (*note Security::),
2340
all you can do is choose an entry by pressing <RET>, or press <p> to
2341
enter the password.
2342
2343
2344
File: grub.info, Node: Menu entry editor, Prev: Menu interface, Up: Interface
2345
2346
12.3 Editing a menu entry
2347
=========================
2348
2349
The menu entry editor looks much like the main menu interface, but the
2350
lines in the menu are individual commands in the selected entry instead
2351
of entry names.
2352
2353
If an <ESC> is pressed in the editor, it aborts all the changes made
2354
to the configuration entry and returns to the main menu interface.
2355
2356
Each line in the menu entry can be edited freely, and you can add
2357
new lines by pressing <RET> at the end of a line. To boot the edited
2358
entry, press <Ctrl-x>.
2359
2360
Although GRUB unfortunately does not support "undo", you can do
2361
almost the same thing by just returning to the main menu using <ESC>.
2362
2363
2364
File: grub.info, Node: Commands, Next: Security, Prev: Interface, Up: Top
2365
2366
13 The list of available commands
2367
*********************************
2368
2369
In this chapter, we list all commands that are available in GRUB.
2370
2371
Commands belong to different groups. A few can only be used in the
2372
global section of the configuration file (or "menu"); most of them can
2373
be entered on the command-line and can be used either anywhere in the
2374
menu or specifically in the menu entries.
2375
2376
In rescue mode, only the `insmod' (*note insmod::), `ls' (*note
2377
ls::), `set' (*note set::), and `unset' (*note unset::) commands are
2378
normally available.
2379
2380
* Menu:
2381
2382
* Menu-specific commands::
2383
* General commands::
2384
* Command-line and menu entry commands::
2385
2386
2387
File: grub.info, Node: Menu-specific commands, Next: General commands, Up: Commands
2388
2389
13.1 The list of commands for the menu only
2390
===========================================
2391
2392
The semantics used in parsing the configuration file are the following:
2393
2394
* The menu-specific commands have to be used before any others.
2395
2396
* The files _must_ be in plain-text format.
2397
2398
* `#' at the beginning of a line in a configuration file means it is
2399
only a comment.
2400
2401
* Options are separated by spaces.
2402
2403
* All numbers can be either decimal or hexadecimal. A hexadecimal
2404
number must be preceded by `0x', and is case-insensitive.
2405
2406
* Extra options or text at the end of the line are ignored unless
2407
otherwise specified.
2408
2409
* Unrecognized commands are added to the current entry, except
2410
before entries start, where they are ignored.
2411
2412
These commands can only be used in the menu:
2413
2414
* Menu:
2415
2416
* menuentry:: Start a menu entry
2417
2418
2419
File: grub.info, Node: menuentry, Up: Menu-specific commands
2420
2421
13.1.1 menuentry
2422
----------------
2423
2424
-- Command: menuentry TITLE [`--class=class' ...] [`--users=users']
2425
[`--hotkey=key'] { COMMAND; ... }
2426
This defines a GRUB menu entry named TITLE. When this entry is
2427
selected from the menu, GRUB will set the CHOSEN environment
2428
variable to TITLE, execute the list of commands given within
2429
braces, and if the last command in the list returned successfully
2430
and a kernel was loaded it will execute the `boot' command.
2431
2432
The `--class' option may be used any number of times to group menu
2433
entries into classes. Menu themes may display different classes
2434
using different styles.
2435
2436
The `--users' option grants specific users access to specific menu
2437
entries. *Note Security::.
2438
2439
The `--hotkey' option associates a hotkey with a menu entry. KEY
2440
may be a single letter, or one of the aliases `backspace', `tab',
2441
or `delete'.
2442
2443
2444
File: grub.info, Node: General commands, Next: Command-line and menu entry commands, Prev: Menu-specific commands, Up: Commands
2445
2446
13.2 The list of general commands
2447
=================================
2448
2449
Commands usable anywhere in the menu and in the command-line.
2450
2451
* Menu:
2452
2453
* serial:: Set up a serial device
2454
* terminal_input:: Manage input terminals
2455
* terminal_output:: Manage output terminals
2456
* terminfo:: Define terminal type
2457
2458
2459
File: grub.info, Node: serial, Next: terminal_input, Up: General commands
2460
2461
13.2.1 serial
2462
-------------
2463
2464
-- Command: serial [`--unit=unit'] [`--port=port'] [`--speed=speed']
2465
[`--word=word'] [`--parity=parity'] [`--stop=stop']
2466
Initialize a serial device. UNIT is a number in the range 0-3
2467
specifying which serial port to use; default is 0, which
2468
corresponds to the port often called COM1. PORT is the I/O port
2469
where the UART is to be found; if specified it takes precedence
2470
over UNIT. SPEED is the transmission speed; default is 9600. WORD
2471
and STOP are the number of data bits and stop bits. Data bits must
2472
be in the range 5-8 and stop bits must be 1 or 2. Default is 8 data
2473
bits and one stop bit. PARITY is one of `no', `odd', `even' and
2474
defaults to `no'.
2475
2476
The serial port is not used as a communication channel unless the
2477
`terminal_input' or `terminal_output' command is used (*note
2478
terminal_input::, *note terminal_output::).
2479
2480
See also *note Serial terminal::.
2481
2482
2483
File: grub.info, Node: terminal_input, Next: terminal_output, Prev: serial, Up: General commands
2484
2485
13.2.2 terminal_input
2486
---------------------
2487
2488
-- Command: terminal_input [`--append'|`--remove'] [terminal1]
2489
[terminal2] ...
2490
List or select an input terminal.
2491
2492
With no arguments, list the active and available input terminals.
2493
2494
With `--append', add the named terminals to the list of active
2495
input terminals; any of these may be used to provide input to GRUB.
2496
2497
With `--remove', remove the named terminals from the active list.
2498
2499
With no options but a list of terminal names, make only the listed
2500
terminal names active.
2501
2502
2503
File: grub.info, Node: terminal_output, Next: terminfo, Prev: terminal_input, Up: General commands
2504
2505
13.2.3 terminal_output
2506
----------------------
2507
2508
-- Command: terminal_output [`--append'|`--remove'] [terminal1]
2509
[terminal2] ...
2510
List or select an output terminal.
2511
2512
With no arguments, list the active and available output terminals.
2513
2514
With `--append', add the named terminals to the list of active
2515
output terminals; all of these will receive output from GRUB.
2516
2517
With `--remove', remove the named terminals from the active list.
2518
2519
With no options but a list of terminal names, make only the listed
2520
terminal names active.
2521
2522
2523
File: grub.info, Node: terminfo, Prev: terminal_output, Up: General commands
2524
2525
13.2.4 terminfo
2526
---------------
2527
2528
-- Command: terminfo [-a|-u|-v] [term]
2529
Define the capabilities of your terminal by giving the name of an
2530
entry in the terminfo database, which should correspond roughly to
2531
a `TERM' environment variable in Unix.
2532
2533
The currently available terminal types are `vt100', `vt100-color',
2534
`ieee1275', and `dumb'. If you need other terminal types, please
2535
contact us to discuss the best way to include support for these in
2536
GRUB.
2537
2538
The `-a' (`--ascii'), `-u' (`--utf8'), and `-v' (`--visual-utf8')
2539
options control how non-ASCII text is displayed. `-a' specifies
2540
an ASCII-only terminal; `-u' specifies logically-ordered UTF-8;
2541
and `-v' specifies "visually-ordered UTF-8" (in other words,
2542
arranged such that a terminal emulator without bidirectional text
2543
support will display right-to-left text in the proper order; this
2544
is not really proper UTF-8, but a workaround).
2545
2546
If no option or terminal type is specified, the current terminal
2547
type is printed.
2548
2549
2550
File: grub.info, Node: Command-line and menu entry commands, Prev: General commands, Up: Commands
2551
2552
13.3 The list of command-line and menu entry commands
2553
=====================================================
2554
2555
These commands are usable in the command-line and in menu entries. If
2556
you forget a command, you can run the command `help' (*note help::).
2557
2558
* Menu:
2559
2560
* acpi:: Load ACPI tables
2561
* badram:: Filter out bad regions of RAM
2562
* blocklist:: Print a block list
2563
* boot:: Start up your operating system
2564
* cat:: Show the contents of a file
2565
* chainloader:: Chain-load another boot loader
2566
* cmp:: Compare two files
2567
* configfile:: Load a configuration file
2568
* cpuid:: Check for CPU features
2569
* crc:: Calculate CRC32 checksums
2570
* date:: Display or set current date and time
2571
* drivemap:: Map a drive to another
2572
* echo:: Display a line of text
2573
* export:: Export an environment variable
2574
* gettext:: Translate a string
2575
* gptsync:: Fill an MBR based on GPT entries
2576
* halt:: Shut down your computer
2577
* help:: Show help messages
2578
* initrd:: Load a Linux initrd
2579
* initrd16:: Load a Linux initrd (16-bit mode)
2580
* insmod:: Insert a module
2581
* keystatus:: Check key modifier status
2582
* linux:: Load a Linux kernel
2583
* linux16:: Load a Linux kernel (16-bit mode)
2584
* ls:: List devices or files
2585
* parttool:: Modify partition table entries
2586
* password:: Set a clear-text password
2587
* password_pbkdf2:: Set a hashed password
2588
* play:: Play a tune
2589
* pxe_unload:: Unload the PXE environment
2590
* reboot:: Reboot your computer
2591
* search:: Search devices by file, label, or UUID
2592
* sendkey:: Emulate keystrokes
2593
* set:: Set an environment variable
2594
* unset:: Unset an environment variable
2595
* uppermem:: Set the upper memory size
2596
2597
2598
File: grub.info, Node: acpi, Next: badram, Up: Command-line and menu entry commands
2599
2600
13.3.1 acpi
2601
-----------
2602
2603
-- Command: acpi [`-1'|`-2']
2604
[`--exclude=table1,...'|`--load-only=table1,...']
2605
[`--oemid=id'] [`--oemtable=table'] [`--oemtablerev=rev']
2606
[`--oemtablecreator=creator'] [`--oemtablecreatorrev=rev']
2607
[`--no-ebda'] filename ...
2608
Modern BIOS systems normally implement the Advanced Configuration
2609
and Power Interface (ACPI), and define various tables that
2610
describe the interface between an ACPI-compliant operating system
2611
and the firmware. In some cases, the tables provided by default
2612
only work well with certain operating systems, and it may be
2613
necessary to replace some of them.
2614
2615
Normally, this command will replace the Root System Description
2616
Pointer (RSDP) in the Extended BIOS Data Area to point to the new
2617
tables. If the `--no-ebda' option is used, the new tables will be
2618
known only to GRUB, but may be used by GRUB's EFI emulation.
2619
2620
2621
File: grub.info, Node: badram, Next: blocklist, Prev: acpi, Up: Command-line and menu entry commands
2622
2623
13.3.2 badram
2624
-------------
2625
2626
-- Command: badram addr,mask[,addr,mask...]
2627
Filter out bad RAM.
2628
2629
This command notifies the memory manager that specified regions of
2630
RAM ought to be filtered out (usually, because they're damaged). This
2631
remains in effect after a payload kernel has been loaded by GRUB, as
2632
long as the loaded kernel obtains its memory map from GRUB. Kernels
2633
that support this include Linux, GNU Mach, the kernel of FreeBSD and
2634
Multiboot kernels in general.
2635
2636
Syntax is the same as provided by the Memtest86+ utility
2637
(http://www.memtest.org/): a list of address/mask pairs. Given a
2638
page-aligned address and a base address / mask pair, if all the bits of
2639
the page-aligned address that are enabled by the mask match with the
2640
base address, it means this page is to be filtered. This syntax makes
2641
it easy to represent patterns that are often result of memory damage,
2642
due to physical distribution of memory cells.
2643
2644
2645
File: grub.info, Node: blocklist, Next: boot, Prev: badram, Up: Command-line and menu entry commands
2646
2647
13.3.3 blocklist
2648
----------------
2649
2650
-- Command: blocklist file
2651
Print a block list (*note Block list syntax::) for FILE.
2652
2653
2654
File: grub.info, Node: boot, Next: cat, Prev: blocklist, Up: Command-line and menu entry commands
2655
2656
13.3.4 boot
2657
-----------
2658
2659
-- Command: boot
2660
Boot the OS or chain-loader which has been loaded. Only necessary
2661
if running the fully interactive command-line (it is implicit at
2662
the end of a menu entry).
2663
2664
2665
File: grub.info, Node: cat, Next: chainloader, Prev: boot, Up: Command-line and menu entry commands
2666
2667
13.3.5 cat
2668
----------
2669
2670
-- Command: cat [`--dos'] file
2671
Display the contents of the file FILE. This command may be useful
2672
to remind you of your OS's root partition:
2673
2674
grub> cat /etc/fstab
2675
2676
If the `--dos' option is used, then carriage return / new line
2677
pairs will be displayed as a simple new line. Otherwise, the
2678
carriage return will be displayed as a control character (`<d>')
2679
to make it easier to see when boot problems are caused by a file
2680
formatted using DOS-style line endings.
2681
2682
2683
File: grub.info, Node: chainloader, Next: cmp, Prev: cat, Up: Command-line and menu entry commands
2684
2685
13.3.6 chainloader
2686
------------------
2687
2688
-- Command: chainloader [`--force'] file
2689
Load FILE as a chain-loader. Like any other file loaded by the
2690
filesystem code, it can use the blocklist notation (*note Block
2691
list syntax::) to grab the first sector of the current partition
2692
with `+1'. If you specify the option `--force', then load FILE
2693
forcibly, whether it has a correct signature or not. This is
2694
required when you want to load a defective boot loader, such as
2695
SCO UnixWare 7.1.
2696
2697
2698
File: grub.info, Node: cmp, Next: configfile, Prev: chainloader, Up: Command-line and menu entry commands
2699
2700
13.3.7 cmp
2701
----------
2702
2703
-- Command: cmp file1 file2
2704
Compare the file FILE1 with the file FILE2. If they differ in
2705
size, print the sizes like this:
2706
2707
Differ in size: 0x1234 [foo], 0x4321 [bar]
2708
2709
If the sizes are equal but the bytes at an offset differ, then
2710
print the bytes like this:
2711
2712
Differ at the offset 777: 0xbe [foo], 0xef [bar]
2713
2714
If they are completely identical, nothing will be printed.
2715
2716
2717
File: grub.info, Node: configfile, Next: cpuid, Prev: cmp, Up: Command-line and menu entry commands
2718
2719
13.3.8 configfile
2720
-----------------
2721
2722
-- Command: configfile file
2723
Load FILE as a configuration file. If FILE defines any menu
2724
entries, then show a menu containing them immediately.
2725
2726
2727
File: grub.info, Node: cpuid, Next: crc, Prev: configfile, Up: Command-line and menu entry commands
2728
2729
13.3.9 cpuid
2730
------------
2731
2732
-- Command: cpuid [-l]
2733
Check for CPU features. This command is only available on x86
2734
systems.
2735
2736
With the `-l' option, return true if the CPU supports long mode
2737
(64-bit).
2738
2739
If invoked without options, this command currently behaves as if
2740
it had been invoked with `-l'. This may change in the future.
2741
2742
2743
File: grub.info, Node: crc, Next: date, Prev: cpuid, Up: Command-line and menu entry commands
2744
2745
13.3.10 crc
2746
-----------
2747
2748
-- Command: crc file
2749
Display the CRC32 checksum of FILE.
2750
2751
2752
File: grub.info, Node: date, Next: drivemap, Prev: crc, Up: Command-line and menu entry commands
2753
2754
13.3.11 date
2755
------------
2756
2757
-- Command: date [[year-]month-day] [hour:minute[:second]]
2758
With no arguments, print the current date and time.
2759
2760
Otherwise, take the current date and time, change any elements
2761
specified as arguments, and set the result as the new date and
2762
time. For example, `date 01-01' will set the current month and
2763
day to January 1, but leave the year, hour, minute, and second
2764
unchanged.
2765
2766
2767
File: grub.info, Node: drivemap, Next: echo, Prev: date, Up: Command-line and menu entry commands
2768
2769
13.3.12 drivemap
2770
----------------
2771
2772
-- Command: drivemap `-l'|`-r'|[`-s'] from_drive to_drive
2773
Without options, map the drive FROM_DRIVE to the drive TO_DRIVE.
2774
This is necessary when you chain-load some operating systems, such
2775
as DOS, if such an OS resides at a non-first drive. For
2776
convenience, any partition suffix on the drive is ignored, so you
2777
can safely use ${root} as a drive specification.
2778
2779
With the `-s' option, perform the reverse mapping as well, swapping
2780
the two drives.
2781
2782
With the `-l' option, list the current mappings.
2783
2784
With the `-r' option, reset all mappings to the default values.
2785
2786
For example:
2787
2788
drivemap -s (hd0) (hd1)
2789
2790
2791
File: grub.info, Node: echo, Next: export, Prev: drivemap, Up: Command-line and menu entry commands
2792
2793
13.3.13 echo
2794
------------
2795
2796
-- Command: echo [`-n'] [`-e'] string ...
2797
Display the requested text and, unless the `-n' option is used, a
2798
trailing new line. If there is more than one string, they are
2799
separated by spaces in the output. As usual in GRUB commands,
2800
variables may be substituted using `${var}'.
2801
2802
The `-e' option enables interpretation of backslash escapes. The
2803
following sequences are recognised:
2804
2805
`\\'
2806
backslash
2807
2808
`\a'
2809
alert (BEL)
2810
2811
`\c'
2812
suppress trailing new line
2813
2814
`\f'
2815
form feed
2816
2817
`\n'
2818
new line
2819
2820
`\r'
2821
carriage return
2822
2823
`\t'
2824
horizontal tab
2825
2826
`\v'
2827
vertical tab
2828
2829
When interpreting backslash escapes, backslash followed by any
2830
other character will print that character.
2831
2832
2833
File: grub.info, Node: export, Next: gettext, Prev: echo, Up: Command-line and menu entry commands
2834
2835
13.3.14 export
2836
--------------
2837
2838
-- Command: export envvar
2839
Export the environment variable ENVVAR. Exported variables are
2840
visible to subsidiary configuration files loaded using
2841
`configfile'.
2842
2843
2844
File: grub.info, Node: gettext, Next: gptsync, Prev: export, Up: Command-line and menu entry commands
2845
2846
13.3.15 gettext
2847
---------------
2848
2849
-- Command: gettext string
2850
Translate STRING into the current language.
2851
2852
The current language code is stored in the `lang' variable in
2853
GRUB's environment. Translation files in MO format are read from
2854
`locale_dir', usually `/boot/grub/locale'.
2855
2856
2857
File: grub.info, Node: gptsync, Next: halt, Prev: gettext, Up: Command-line and menu entry commands
2858
2859
13.3.16 gptsync
2860
---------------
2861
2862
-- Command: gptsync device [partition[+/-[type]]] ...
2863
Disks using the GUID Partition Table (GPT) also have a legacy
2864
Master Boot Record (MBR) partition table for compatibility with
2865
the BIOS and with older operating systems. The legacy MBR can
2866
only represent a limited subset of GPT partition entries.
2867
2868
This command populates the legacy MBR with the specified PARTITION
2869
entries on DEVICE. Up to three partitions may be used.
2870
2871
TYPE is an MBR partition type code; prefix with `0x' if you want
2872
to enter this in hexadecimal. The separator between PARTITION and
2873
TYPE may be `+' to make the partition active, or `-' to make it
2874
inactive; only one partition may be active. If both the separator
2875
and type are omitted, then the partition will be inactive.
2876
2877
2878
File: grub.info, Node: halt, Next: help, Prev: gptsync, Up: Command-line and menu entry commands
2879
2880
13.3.17 halt
2881
------------
2882
2883
-- Command: halt `--no-apm'
2884
The command halts the computer. If the `--no-apm' option is
2885
specified, no APM BIOS call is performed. Otherwise, the computer
2886
is shut down using APM.
2887
2888
2889
File: grub.info, Node: help, Next: initrd, Prev: halt, Up: Command-line and menu entry commands
2890
2891
13.3.18 help
2892
------------
2893
2894
-- Command: help [pattern ...]
2895
Display helpful information about builtin commands. If you do not
2896
specify PATTERN, this command shows short descriptions of all
2897
available commands.
2898
2899
If you specify any PATTERNS, it displays longer information about
2900
each of the commands whose names begin with those PATTERNS.
2901
2902
2903
File: grub.info, Node: initrd, Next: initrd16, Prev: help, Up: Command-line and menu entry commands
2904
2905
13.3.19 initrd
2906
--------------
2907
2908
-- Command: initrd file
2909
Load an initial ramdisk for a Linux kernel image, and set the
2910
appropriate parameters in the Linux setup area in memory. This
2911
may only be used after the `linux' command (*note linux::) has
2912
been run. See also *note GNU/Linux::.
2913
2914
2915
File: grub.info, Node: initrd16, Next: insmod, Prev: initrd, Up: Command-line and menu entry commands
2916
2917
13.3.20 initrd16
2918
----------------
2919
2920
-- Command: initrd16 file
2921
Load an initial ramdisk for a Linux kernel image to be booted in
2922
16-bit mode, and set the appropriate parameters in the Linux setup
2923
area in memory. This may only be used after the `linux16' command
2924
(*note linux16::) has been run. See also *note GNU/Linux::.
2925
2926
This command is only available on x86 systems.
2927
2928
2929
File: grub.info, Node: insmod, Next: keystatus, Prev: initrd16, Up: Command-line and menu entry commands
2930
2931
13.3.21 insmod
2932
--------------
2933
2934
-- Command: insmod module
2935
Insert the dynamic GRUB module called MODULE.
2936
2937
2938
File: grub.info, Node: keystatus, Next: linux, Prev: insmod, Up: Command-line and menu entry commands
2939
2940
13.3.22 keystatus
2941
-----------------
2942
2943
-- Command: keystatus [`--shift'] [`--ctrl'] [`--alt']
2944
Return true if the Shift, Control, or Alt modifier keys are held
2945
down, as requested by options. This is useful in scripting, to
2946
allow some user control over behaviour without having to wait for
2947
a keypress.
2948
2949
Checking key modifier status is only supported on some platforms.
2950
If invoked without any options, the `keystatus' command returns
2951
true if and only if checking key modifier status is supported.
2952
2953
2954
File: grub.info, Node: linux, Next: linux16, Prev: keystatus, Up: Command-line and menu entry commands
2955
2956
13.3.23 linux
2957
-------------
2958
2959
-- Command: linux file ...
2960
Load a Linux kernel image from FILE. The rest of the line is
2961
passed verbatim as the "kernel command-line". Any initrd must be
2962
reloaded after using this command (*note initrd::).
2963
2964
On x86 systems, the kernel will be booted using the 32-bit boot
2965
protocol. Note that this means that the `vga=' boot option will
2966
not work; if you want to set a special video mode, you will need
2967
to use GRUB commands such as `set gfxpayload=1024x768' or `set
2968
gfxpayload=keep' (to keep the same mode as used in GRUB) instead.
2969
GRUB can automatically detect some uses of `vga=' and translate
2970
them to appropriate settings of `gfxpayload'. The `linux16'
2971
command (*note linux16::) avoids this restriction.
2972
2973
2974
File: grub.info, Node: linux16, Next: ls, Prev: linux, Up: Command-line and menu entry commands
2975
2976
13.3.24 linux16
2977
---------------
2978
2979
-- Command: linux16 file ...
2980
Load a Linux kernel image from FILE in 16-bit mode. The rest of
2981
the line is passed verbatim as the "kernel command-line". Any
2982
initrd must be reloaded after using this command (*note
2983
initrd16::).
2984
2985
The kernel will be booted using the traditional 16-bit boot
2986
protocol. As well as bypassing problems with `vga=' described in
2987
*note linux::, this permits booting some other programs that
2988
implement the Linux boot protocol for the sake of convenience.
2989
2990
This command is only available on x86 systems.
2991
2992
2993
File: grub.info, Node: ls, Next: parttool, Prev: linux16, Up: Command-line and menu entry commands
2994
2995
13.3.25 ls
2996
----------
2997
2998
-- Command: ls [arg ...]
2999
List devices or files.
3000
3001
With no arguments, print all devices known to GRUB.
3002
3003
If the argument is a device name enclosed in parentheses (*note
3004
Device syntax::), then list all files at the root directory of
3005
that device.
3006
3007
If the argument is a directory given as an absolute file name
3008
(*note File name syntax::), then list the contents of that
3009
directory.
3010
3011
3012
File: grub.info, Node: parttool, Next: password, Prev: ls, Up: Command-line and menu entry commands
3013
3014
13.3.26 parttool
3015
----------------
3016
3017
-- Command: parttool partition commands
3018
Make various modifications to partition table entries.
3019
3020
Each COMMAND is either a boolean option, in which case it must be
3021
followed with `+' or `-' (with no intervening space) to enable or
3022
disable that option, or else it takes a value in the form
3023
`COMMAND=VALUE'.
3024
3025
Currently, `parttool' is only useful on DOS partition tables (also
3026
known as Master Boot Record, or MBR). On these partition tables,
3027
the following commands are available:
3028
3029
`boot' (boolean)
3030
When enabled, this makes the selected partition be the active
3031
(bootable) partition on its disk, clearing the active flag on
3032
all other partitions. This command is limited to _primary_
3033
partitions.
3034
3035
`type' (value)
3036
Change the type of an existing partition. The value must be
3037
a number in the range 0-0xFF (prefix with `0x' to enter it in
3038
hexadecimal).
3039
3040
`hidden' (boolean)
3041
When enabled, this hides the selected partition by setting
3042
the "hidden" bit in its partition type code; when disabled,
3043
unhides the selected partition by clearing this bit. This is
3044
useful only when booting DOS or Wwindows and multiple primary
3045
FAT partitions exist in one disk. See also *note
3046
DOS/Windows::.
3047
3048
3049
File: grub.info, Node: password, Next: password_pbkdf2, Prev: parttool, Up: Command-line and menu entry commands
3050
3051
13.3.27 password
3052
----------------
3053
3054
-- Command: password user clear-password
3055
Define a user named USER with password CLEAR-PASSWORD. *Note
3056
Security::.
3057
3058
3059
File: grub.info, Node: password_pbkdf2, Next: play, Prev: password, Up: Command-line and menu entry commands
3060
3061
13.3.28 password_pbkdf2
3062
-----------------------
3063
3064
-- Command: password_pbkdf2 user hashed-password
3065
Define a user named USER with password hash HASHED-PASSWORD. Use
3066
`grub-mkpasswd-pbkdf2' (*note Invoking grub-mkpasswd-pbkdf2::) to
3067
generate password hashes. *Note Security::.
3068
3069
3070
File: grub.info, Node: play, Next: pxe_unload, Prev: password_pbkdf2, Up: Command-line and menu entry commands
3071
3072
13.3.29 play
3073
------------
3074
3075
-- Command: play file | tempo [pitch1 duration1] [pitch2 duration2] ...
3076
Plays a tune
3077
3078
If the argument is a file name (*note File name syntax::), play
3079
the tune recorded in it. The file format is first the tempo as an
3080
unsigned 32bit little-endian number, then pairs of unsigned 16bit
3081
little-endian numbers for pitch and duration pairs.
3082
3083
If the arguments are a series of numbers, play the inline tune.
3084
3085
The tempo is the base for all note durations. 60 gives a 1-second
3086
base, 120 gives a half-second base, etc. Pitches are Hz. Set
3087
pitch to 0 to produce a rest.
3088
3089
3090
File: grub.info, Node: pxe_unload, Next: reboot, Prev: play, Up: Command-line and menu entry commands
3091
3092
13.3.30 pxe_unload
3093
------------------
3094
3095
-- Command: pxe_unload
3096
Unload the PXE environment (*note Network::).
3097
3098
This command is only available on PC BIOS systems.
3099
3100
3101
File: grub.info, Node: reboot, Next: search, Prev: pxe_unload, Up: Command-line and menu entry commands
3102
3103
13.3.31 reboot
3104
--------------
3105
3106
-- Command: reboot
3107
Reboot the computer.
3108
3109
3110
File: grub.info, Node: search, Next: sendkey, Prev: reboot, Up: Command-line and menu entry commands
3111
3112
13.3.32 search
3113
--------------
3114
3115
-- Command: search [`--file'|`--label'|`--fs-uuid'] [`--set' [var]]
3116
[`--no-floppy'] name
3117
Search devices by file (`-f', `--file'), filesystem label (`-l',
3118
`--label'), or filesystem UUID (`-u', `--fs-uuid').
3119
3120
If the `--set' option is used, the first device found is set as the
3121
value of environment variable VAR. The default variable is `root'.
3122
3123
The `--no-floppy' option prevents searching floppy devices, which
3124
can be slow.
3125
3126
The `search.file', `search.fs_label', and `search.fs_uuid'
3127
commands are aliases for `search --file', `search --label', and
3128
`search --fs-uuid' respectively.
3129
3130
3131
File: grub.info, Node: sendkey, Next: set, Prev: search, Up: Command-line and menu entry commands
3132
3133
13.3.33 sendkey
3134
---------------
3135
3136
-- Command: sendkey [`--num'|`--caps'|`--scroll'|`--insert'|
3137
`--pause'|`--left-shift'|`--right-shift'|
3138
`--sysrq'|`--numkey'|`--capskey'|`--scrollkey'|
3139
`--insertkey'|`--left-alt'|`--right-alt'|
3140
`--left-ctrl'|`--right-ctrl' `on'|`off']... [`no-led']
3141
keystroke
3142
Insert keystrokes into the keyboard buffer when booting.
3143
Sometimes an operating system or chainloaded boot loader requires
3144
particular keys to be pressed: for example, one might need to
3145
press a particular key to enter "safe mode", or when chainloading
3146
another boot loader one might send keystrokes to it to navigate
3147
its menu.
3148
3149
You may provide up to 16 keystrokes (the length of the BIOS
3150
keyboard buffer). Keystroke names may be upper-case or lower-case
3151
letters, digits, or taken from the following table:
3152
3153
Name Key
3154
---------------------------------------------------------------
3155
escape Escape
3156
exclam !
3157
at @
3158
numbersign #
3159
dollar $
3160
percent %
3161
caret ^
3162
ampersand &
3163
asterisk *
3164
parenleft (
3165
parenright )
3166
minus -
3167
underscore _
3168
equal =
3169
plus +
3170
backspace Backspace
3171
tab Tab
3172
bracketleft [
3173
braceleft {
3174
bracketright ]
3175
braceright }
3176
enter Enter
3177
control press and release Control
3178
semicolon ;
3179
colon :
3180
quote '
3181
doublequote "
3182
backquote `
3183
tilde ~
3184
shift press and release left Shift
3185
backslash \
3186
bar |
3187
comma ,
3188
less <
3189
period .
3190
greater >
3191
slash /
3192
question ?
3193
rshift press and release right Shift
3194
alt press and release Alt
3195
space space bar
3196
capslock Caps Lock
3197
F1 F1
3198
F2 F2
3199
F3 F3
3200
F4 F4
3201
F5 F5
3202
F6 F6
3203
F7 F7
3204
F8 F8
3205
F9 F9
3206
F10 F10
3207
F11 F11
3208
F12 F12
3209
num1 1 (numeric keypad)
3210
num2 2 (numeric keypad)
3211
num3 3 (numeric keypad)
3212
num4 4 (numeric keypad)
3213
num5 5 (numeric keypad)
3214
num6 6 (numeric keypad)
3215
num7 7 (numeric keypad)
3216
num8 8 (numeric keypad)
3217
num9 9 (numeric keypad)
3218
num0 0 (numeric keypad)
3219
numperiod . (numeric keypad)
3220
numend End (numeric keypad)
3221
numdown Down (numeric keypad)
3222
numpgdown Page Down (numeric keypad)
3223
numleft Left (numeric keypad)
3224
numcenter 5 with Num Lock inactive (numeric
3225
keypad)
3226
numright Right (numeric keypad)
3227
numhome Home (numeric keypad)
3228
numup Up (numeric keypad)
3229
numpgup Page Up (numeric keypad)
3230
numinsert Insert (numeric keypad)
3231
numdelete Delete (numeric keypad)
3232
numasterisk * (numeric keypad)
3233
numminus - (numeric keypad)
3234
numplus + (numeric keypad)
3235
numslash / (numeric keypad)
3236
numenter Enter (numeric keypad)
3237
delete Delete
3238
insert Insert
3239
home Home
3240
end End
3241
pgdown Page Down
3242
pgup Page Up
3243
down Down
3244
up Up
3245
left Left
3246
right Right
3247
3248
As well as keystrokes, the `sendkey' command takes various options
3249
that affect the BIOS keyboard status flags. These options take an
3250
`on' or `off' parameter, specifying that the corresponding status
3251
flag be set or unset; omitting the option for a given status flag
3252
will leave that flag at its initial state at boot. The `--num',
3253
`--caps', `--scroll', and `--insert' options emulate setting the
3254
corresponding mode, while the `--numkey', `--capskey',
3255
`--scrollkey', and `--insertkey' options emulate pressing and
3256
holding the corresponding key. The other status flag options are
3257
self-explanatory.
3258
3259
If the `--no-led' option is given, the status flag options will
3260
have no effect on keyboard LEDs.
3261
3262
If the `sendkey' command is given multiple times, then only the
3263
last invocation has any effect.
3264
3265
Since `sendkey' manipulates the BIOS keyboard buffer, it may cause
3266
hangs, reboots, or other misbehaviour on some systems. If the
3267
operating system or boot loader that runs after GRUB uses its own
3268
keyboard driver rather than the BIOS keyboard functions, then
3269
`sendkey' will have no effect.
3270
3271
This command is only available on PC BIOS systems.
3272
3273
3274
File: grub.info, Node: set, Next: unset, Prev: sendkey, Up: Command-line and menu entry commands
3275
3276
13.3.34 set
3277
-----------
3278
3279
-- Command: set [envvar=value]
3280
Set the environment variable ENVVAR to VALUE. If invoked with no
3281
arguments, print all environment variables with their values.
3282
3283
3284
File: grub.info, Node: unset, Next: uppermem, Prev: set, Up: Command-line and menu entry commands
3285
3286
13.3.35 unset
3287
-------------
3288
3289
-- Command: unset envvar
3290
Unset the environment variable ENVVAR.
3291
3292
3293
File: grub.info, Node: uppermem, Prev: unset, Up: Command-line and menu entry commands
3294
3295
13.3.36 uppermem
3296
----------------
3297
3298
This command is not yet implemented for GRUB 2, although it is planned.
3299
3300
3301
File: grub.info, Node: Security, Next: Supported kernels, Prev: Commands, Up: Top
3302
3303
14 Authentication and authorisation
3304
***********************************
3305
3306
By default, the boot loader interface is accessible to anyone with
3307
physical access to the console: anyone can select and edit any menu
3308
entry, and anyone can get direct access to a GRUB shell prompt. For
3309
most systems, this is reasonable since anyone with direct physical
3310
access has a variety of other ways to gain full access, and requiring
3311
authentication at the boot loader level would only serve to make it
3312
difficult to recover broken systems.
3313
3314
However, in some environments, such as kiosks, it may be appropriate
3315
to lock down the boot loader to require authentication before
3316
performing certain operations.
3317
3318
The `password' (*note password::) and `password_pbkdf2' (*note
3319
password_pbkdf2::) commands can be used to define users, each of which
3320
has an associated password. `password' sets the password in plain
3321
text, requiring `grub.cfg' to be secure; `password_pbkdf2' sets the
3322
password hashed using the Password-Based Key Derivation Function (RFC
3323
2898), requiring the use of `grub-mkpasswd-pbkdf2' (*note Invoking
3324
grub-mkpasswd-pbkdf2::) to generate password hashes.
3325
3326
In order to enable authentication support, the `superusers'
3327
environment variable must be set to a list of usernames, separated by
3328
any of spaces, commas, semicolons, pipes, or ampersands. Superusers
3329
are permitted to use the GRUB command line, edit menu entries, and
3330
execute any menu entry. If `superusers' is set, then use of the
3331
command line is automatically restricted to superusers.
3332
3333
Other users may be given access to specific menu entries by giving a
3334
list of usernames (as above) using the `--users' option to the
3335
`menuentry' command (*note menuentry::). If the `--users' option is
3336
not used for a menu entry, then that entry is unrestricted.
3337
3338
Putting this together, a typical `grub.cfg' fragment might look like
3339
this:
3340
3341
set superusers="root"
3342
password_pbkdf2 root grub.pbkdf2.sha512.10000.biglongstring
3343
password user1 insecure
3344
3345
menuentry "May be run by any user" {
3346
set root=(hd0,1)
3347
linux /vmlinuz
3348
}
3349
3350
menuentry "Superusers only" --users "" {
3351
set root=(hd0,1)
3352
linux /vmlinuz single
3353
}
3354
3355
menuentry "May be run by user1 or a superuser" --users user1 {
3356
set root=(hd0,2)
3357
chainloader +1
3358
}
3359
3360
The `grub-mkconfig' program does not yet have built-in support for
3361
generating configuration files with authentication. You can use
3362
`/etc/grub.d/40_custom' to add simple superuser authentication, by
3363
adding `set superusers=' and `password' or `password_pbkdf2' commands.
3364
3365
3366
File: grub.info, Node: Supported kernels, Next: Troubleshooting, Prev: Security, Up: Top
3367
3368
15 Supported boot targets
3369
*************************
3370
3371
X86 support is summarised in the following table. "Yes" means that the
3372
kernel works on the given platform, "crashes" means an early kernel
3373
crash which we hope will be fixed by concerned kernel developers. "no"
3374
means GRUB doesn't load the given kernel on a given platform.
3375
"headless" means that the kernel works but lacks console drivers (you
3376
can still use serial or network console). In case of "no" and
3377
"crashes" the reason is given in footnote.
3378
BIOS Coreboot
3379
BIOS chainloading yes no (1)
3380
NTLDR yes no (1)
3381
FreeBSD bootloader yes crashes (1)
3382
32-bit kFreeBSD yes crashes (2,6)
3383
64-bit kFreeBSD yes crashes (2,6)
3384
32-bit kNetBSD yes crashes (1)
3385
64-bit kNetBSD yes crashes (2)
3386
32-bit kOpenBSD yes yes
3387
64-bit kOpenBSD yes yes
3388
Multiboot yes yes
3389
Multiboot2 yes yes
3390
32-bit Linux (legacy protocol) yes no (1)
3391
64-bit Linux (legacy protocol) yes no (1)
3392
32-bit Linux (modern protocol) yes yes
3393
64-bit Linux (modern protocol) yes yes
3394
32-bit XNU yes ?
3395
64-bit XNU yes ?
3396
32-bit EFI chainloader no (3) no (3)
3397
64-bit EFI chainloader no (3) no (3)
3398
Appleloader no (3) no (3)
3399
3400
Multiboot Qemu
3401
BIOS chainloading no (1) no (1)
3402
NTLDR no (1) no (1)
3403
FreeBSD bootloader crashes (1) crashes (1)
3404
32-bit kFreeBSD crashes (6) crashes (6)
3405
64-bit kFreeBSD crashes (6) crashes (6)
3406
32-bit kNetBSD crashes (1) crashes (1)
3407
64-bit kNetBSD yes yes
3408
32-bit kOpenBSD yes yes
3409
64-bit kOpenBSD yes yes
3410
Multiboot yes yes
3411
Multiboot2 yes yes
3412
32-bit Linux (legacy protocol) no (1) no (1)
3413
64-bit Linux (legacy protocol) no (1) no (1)
3414
32-bit Linux (modern protocol) yes yes
3415
64-bit Linux (modern protocol) yes yes
3416
32-bit XNU ? ?
3417
64-bit XNU ? ?
3418
32-bit EFI chainloader no (3) no (3)
3419
64-bit EFI chainloader no (3) no (3)
3420
Appleloader no (3) no (3)
3421
3422
32-bit EFI 64-bit EFI
3423
BIOS chainloading no (1) no (1)
3424
NTLDR no (1) no (1)
3425
FreeBSD bootloader crashes (1) crashes (1)
3426
32-bit kFreeBSD headless headless
3427
64-bit kFreeBSD headless headless
3428
32-bit kNetBSD crashes (1) crashes (1)
3429
64-bit kNetBSD yes yes
3430
32-bit kOpenBSD headless headless
3431
64-bit kOpenBSD headless headless
3432
Multiboot yes yes
3433
Multiboot2 yes yes
3434
32-bit Linux (legacy protocol) no (1) no (1)
3435
64-bit Linux (legacy protocol) no (1) no (1)
3436
32-bit Linux (modern protocol) yes yes
3437
64-bit Linux (modern protocol) yes yes
3438
32-bit XNU yes yes
3439
64-bit XNU yes (5) yes
3440
32-bit EFI chainloader yes no (4)
3441
64-bit EFI chainloader no (4) yes
3442
Appleloader yes yes
3443
3444
IEEE1275
3445
BIOS chainloading no (1)
3446
NTLDR no (1)
3447
FreeBSD bootloader crashes (1)
3448
32-bit kFreeBSD crashes (6)
3449
64-bit kFreeBSD crashes (6)
3450
32-bit kNetBSD crashes (1)
3451
64-bit kNetBSD ?
3452
32-bit kOpenBSD ?
3453
64-bit kOpenBSD ?
3454
Multiboot ?
3455
Multiboot2 ?
3456
32-bit Linux (legacy protocol) no (1)
3457
64-bit Linux (legacy protocol) no (1)
3458
32-bit Linux (modern protocol) ?
3459
64-bit Linux (modern protocol) ?
3460
32-bit XNU ?
3461
64-bit XNU ?
3462
32-bit EFI chainloader no (3)
3463
64-bit EFI chainloader no (3)
3464
Appleloader no (3)
3465
3466
1. Requires BIOS
3467
3468
2. Crashes because the memory at 0x0-0x1000 isn't available
3469
3470
3. EFI only
3471
3472
4. 32-bit and 64-bit EFI have different structures and work in
3473
different CPU modes so it's not possible to chainload 32-bit
3474
bootloader on 64-bit platform and vice-versa
3475
3476
5. Some modules may need to be disabled
3477
3478
6. Requires ACPI
3479
3480
PowerPC and Sparc ports support only Linux. MIPS port supports Linux
3481
and multiboot2.
3482
3483
16 Boot tests
3484
*************
3485
3486
As you have seen in previous chapter the support matrix is pretty big
3487
and some of the configurations are only rarely used. To ensure the
3488
quality bootchecks are available for all x86 targets except EFI
3489
chainloader, Appleloader and XNU. All x86 platforms have bootcheck
3490
facility except ieee1275. Multiboot, multiboot2, BIOS chainloader,
3491
ntldr and freebsd-bootloader boot targets are tested only with a fake
3492
kernel images. Only Linux is tested among the payloads using Linux
3493
protocols.
3494
3495
Following variables must be defined:
3496
3497
GRUB_PAYLOADS_DIR directory containing the required kernels
3498
GRUB_CBFSTOOL cbfstoll from Coreboot package (for coreboot
3499
platform only)
3500
GRUB_COREBOOT_ROM empty Coreboot ROM
3501
GRUB_QEMU_OPTS additional options to be supplied to QEMU
3502
3503
Required files are:
3504
3505
kfreebsd_env.i386 32-bit kFreeBSD device hints
3506
kfreebsd.i386 32-bit FreeBSD kernel image
3507
kfreebsd.x86_64, same from 64-bit kFreeBSD
3508
kfreebsd_env.x86_64
3509
knetbsd.i386 32-bit NetBSD kernel image
3510
knetbsd.miniroot.i386 32-bit kNetBSD miniroot.kmod.
3511
knetbsd.x86_64, same from 64-bit kNetBSD
3512
knetbsd.miniroot.x86_64
3513
kopenbsd.i386 32-bit OpenBSD kernel bsd.rd image
3514
kopenbsd.x86_64 same from 64-bit kOpenBSD
3515
linux.i386 32-bit Linux
3516
linux.x86_64 64-bit Linux
3517
3518
3519
File: grub.info, Node: Troubleshooting, Next: Invoking grub-install, Prev: Supported kernels, Up: Top
3520
3521
17 Error messages produced by GRUB
3522
**********************************
3523
3524
* Menu:
3525
3526
* GRUB only offers a rescue shell::
3527
3528
3529
File: grub.info, Node: GRUB only offers a rescue shell, Up: Troubleshooting
3530
3531
17.1 GRUB only offers a rescue shell
3532
====================================
3533
3534
GRUB's normal start-up procedure involves setting the `prefix'
3535
environment variable to a value set in the core image by
3536
`grub-install', setting the `root' variable to match, loading the
3537
`normal' module from the prefix, and running the `normal' command.
3538
This command is responsible for reading `/boot/grub/grub.cfg', running
3539
the menu, and doing all the useful things GRUB is supposed to do.
3540
3541
If, instead, you only get a rescue shell, this usually means that
3542
GRUB failed to load the `normal' module for some reason. It may be
3543
possible to work around this temporarily: for instance, if the reason
3544
for the failure is that `prefix' is wrong (perhaps it refers to the
3545
wrong device, or perhaps the path to `/boot/grub' was not correctly
3546
made relative to the device), then you can correct this and enter
3547
normal mode manually:
3548
3549
# Inspect the current prefix (and other preset variables):
3550
set
3551
# Set to the correct value, which might be something like this:
3552
set prefix=(hd0,1)/grub
3553
set root=(hd0,1)
3554
insmod normal
3555
normal
3556
3557
However, any problem that leaves you in the rescue shell probably
3558
means that GRUB was not correctly installed. It may be more useful to
3559
try to reinstall it properly using `grub-install DEVICE' (*note
3560
Invoking grub-install::). When doing this, there are a few things to
3561
remember:
3562
3563
* Drive ordering in your operating system may not be the same as the
3564
boot drive ordering used by your firmware. Do not assume that
3565
your first hard drive (e.g. `/dev/sda') is the one that your
3566
firmware will boot from. `device.map' (*note Device map::) can be
3567
used to override this, but it is usually better to use UUIDs or
3568
file system labels and avoid depending on drive ordering entirely.
3569
3570
* At least on BIOS systems, if you tell `grub-install' to install
3571
GRUB to a partition but GRUB has already been installed in the
3572
master boot record, then the GRUB installation in the partition
3573
will be ignored.
3574
3575
* If possible, it is generally best to avoid installing GRUB to a
3576
partition (unless it is a special partition for the use of GRUB
3577
alone, such as the BIOS Boot Partition used on GPT). Doing this
3578
means that GRUB may stop being able to read its core image due to
3579
a file system moving blocks around, such as while defragmenting,
3580
running checks, or even during normal operation. Installing to
3581
the whole disk device is normally more robust.
3582
3583
* Check that GRUB actually knows how to read from the device and
3584
file system containing `/boot/grub'. It will not be able to read
3585
from encrypted devices, nor from file systems for which support
3586
has not yet been added to GRUB.
3587
3588
3589
File: grub.info, Node: Invoking grub-install, Next: Invoking grub-mkconfig, Prev: Troubleshooting, Up: Top
3590
3591
18 Invoking grub-install
3592
************************
3593
3594
The program `grub-install' installs GRUB on your drive using
3595
`grub-mkimage' and (on some platforms) `grub-setup'. You must specify
3596
the device name on which you want to install GRUB, like this:
3597
3598
grub-install INSTALL_DEVICE
3599
3600
The device name INSTALL_DEVICE is an OS device name or a GRUB device
3601
name.
3602
3603
`grub-install' accepts the following options:
3604
3605
`--help'
3606
Print a summary of the command-line options and exit.
3607
3608
`--version'
3609
Print the version number of GRUB and exit.
3610
3611
`--root-directory=DIR'
3612
Install GRUB images under the directory DIR instead of the root
3613
directory. This option is useful when you want to install GRUB
3614
into a separate partition or a removable disk. Here is an example
3615
in which you have a separate "boot" partition which is mounted on
3616
`/boot':
3617
3618
grub-install --root-directory=/boot hd0
3619
3620
`--recheck'
3621
Recheck the device map, even if `/boot/grub/device.map' already
3622
exists. You should use this option whenever you add/remove a disk
3623
into/from your computer.
3624
3625
3626
File: grub.info, Node: Invoking grub-mkconfig, Next: Invoking grub-mkpasswd-pbkdf2, Prev: Invoking grub-install, Up: Top
3627
3628
19 Invoking grub-mkconfig
3629
*************************
3630
3631
The program `grub-mkconfig' generates a configuration file for GRUB
3632
(*note Simple configuration::).
3633
3634
grub-mkconfig -o /boot/grub/grub.cfg
3635
3636
`grub-mkconfig' accepts the following options:
3637
3638
`--help'
3639
Print a summary of the command-line options and exit.
3640
3641
`--version'
3642
Print the version number of GRUB and exit.
3643
3644
`-o FILE'
3645
`--output=FILE'
3646
Send the generated configuration file to FILE. The default is to
3647
send it to standard output.
3648
3649
3650
File: grub.info, Node: Invoking grub-mkpasswd-pbkdf2, Next: Obtaining and Building GRUB, Prev: Invoking grub-mkconfig, Up: Top
3651
3652
20 Invoking grub-mkpasswd-pbkdf2
3653
********************************
3654
3655
The program `grub-mkpasswd-pbkdf2' generates password hashes for GRUB
3656
(*note Security::).
3657
3658
grub-mkpasswd-pbkdf2
3659
3660
`grub-mkpasswd-pbkdf2' accepts the following options:
3661
3662
`-c NUMBER'
3663
`--iteration-count=NUMBER'
3664
Number of iterations of the underlying pseudo-random function.
3665
Defaults to 10000.
3666
3667
`-l NUMBER'
3668
`--buflen=NUMBER'
3669
Length of the generated hash. Defaults to 64.
3670
3671
`-s NUMBER'
3672
`--salt=NUMBER'
3673
Length of the salt. Defaults to 64.
3674
3675
3676
File: grub.info, Node: Obtaining and Building GRUB, Next: Reporting bugs, Prev: Invoking grub-mkpasswd-pbkdf2, Up: Top
3677
3678
Appendix A How to obtain and build GRUB
3679
***************************************
3680
3681
*Caution:* GRUB requires binutils-2.9.1.0.23 or later because the
3682
GNU assembler has been changed so that it can produce real 16bits
3683
machine code between 2.9.1 and 2.9.1.0.x. See
3684
`http://sources.redhat.com/binutils/', to obtain information on
3685
how to get the latest version.
3686
3687
GRUB is available from the GNU alpha archive site
3688
`ftp://alpha.gnu.org/gnu/grub' or any of its mirrors. The file will be
3689
named grub-version.tar.gz. The current version is 1.99~rc1, so the file
3690
you should grab is:
3691
3692
`ftp://alpha.gnu.org/gnu/grub/grub-1.99~rc1.tar.gz'
3693
3694
To unbundle GRUB use the instruction:
3695
3696
zcat grub-1.99~rc1.tar.gz | tar xvf -
3697
3698
which will create a directory called `grub-1.99~rc1' with all the
3699
sources. You can look at the file `INSTALL' for detailed instructions
3700
on how to build and install GRUB, but you should be able to just do:
3701
3702
cd grub-1.99~rc1
3703
./configure
3704
make install
3705
3706
Also, the latest version is available using Bazaar. See
3707
`http://www.gnu.org/software/grub/grub-download.en.html' for more
3708
information.
3709
3710
3711
File: grub.info, Node: Reporting bugs, Next: Future, Prev: Obtaining and Building GRUB, Up: Top
3712
3713
Appendix B Reporting bugs
3714
*************************
3715
3716
These are the guideline for how to report bugs. Take a look at this
3717
list below before you submit bugs:
3718
3719
1. Before getting unsettled, read this manual through and through.
3720
Also, see the GNU GRUB FAQ
3721
(http://www.gnu.org/software/grub/grub-faq.html).
3722
3723
2. Always mention the information on your GRUB. The version number
3724
and the configuration are quite important. If you build it
3725
yourself, write the options specified to the configure script and
3726
your operating system, including the versions of gcc and binutils.
3727
3728
3. If you have trouble with the installation, inform us of how you
3729
installed GRUB. Don't omit error messages, if any. Just `GRUB hangs
3730
up when it boots' is not enough.
3731
3732
The information on your hardware is also essential. These are
3733
especially important: the geometries and the partition tables of
3734
your hard disk drives and your BIOS.
3735
3736
4. If GRUB cannot boot your operating system, write down _everything_
3737
you see on the screen. Don't paraphrase them, like `The foo OS
3738
crashes with GRUB, even though it can boot with the bar boot
3739
loader just fine'. Mention the commands you executed, the messages
3740
printed by them, and information on your operating system
3741
including the version number.
3742
3743
5. Explain what you wanted to do. It is very useful to know your
3744
purpose and your wish, and how GRUB didn't satisfy you.
3745
3746
6. If you can investigate the problem yourself, please do. That will
3747
give you and us much more information on the problem. Attaching a
3748
patch is even better.
3749
3750
When you attach a patch, make the patch in unified diff format, and
3751
write ChangeLog entries. But, even when you make a patch, don't
3752
forget to explain the problem, so that we can understand what your
3753
patch is for.
3754
3755
7. Write down anything that you think might be related. Please
3756
understand that we often need to reproduce the same problem you
3757
encounterred in our environment. So your information should be
3758
sufficient for us to do the same thing--Don't forget that we
3759
cannot see your computer directly. If you are not sure whether to
3760
state a fact or leave it out, state it! Reporting too many things
3761
is much better than omitting something important.
3762
3763
If you follow the guideline above, submit a report to the Bug
3764
Tracking System (http://savannah.gnu.org/bugs/?group=grub).
3765
Alternatively, you can submit a report via electronic mail to
3766
<bug-grub@gnu.org>, but we strongly recommend that you use the Bug
3767
Tracking System, because e-mail can be passed over easily.
3768
3769
Once we get your report, we will try to fix the bugs.
3770
3771
3772
File: grub.info, Node: Future, Next: Internals, Prev: Reporting bugs, Up: Top
3773
3774
Appendix C Where GRUB will go
3775
*****************************
3776
3777
We started the next generation of GRUB, GRUB 2. GRUB 2 includes
3778
internationalization, dynamic module loading, real memory management,
3779
multiple architecture support, a scripting language, and many other
3780
nice features. If you are interested in the development of GRUB 2, take
3781
a look at the homepage (http://www.gnu.org/software/grub/grub.html).
3782
3783
3784
File: grub.info, Node: Internals, Next: Copying This Manual, Prev: Future, Up: Top
3785
3786
Appendix D Hacking GRUB
3787
***********************
3788
3789
* Menu:
3790
3791
* Getting the source code::
3792
* Finding your way around::
3793
3794
3795
File: grub.info, Node: Getting the source code, Next: Finding your way around, Up: Internals
3796
3797
D.1 Getting the source code
3798
===========================
3799
3800
GRUB is maintained using the Bazaar revision control system
3801
(http://bazaar-vcs.org/). To fetch the primary development branch:
3802
3803
bzr get http://bzr.savannah.gnu.org/r/grub/trunk/grub
3804
3805
The GRUB developers maintain several other branches with work in
3806
progress. Of these, the most interesting is the experimental branch,
3807
which is a staging area for new code which we expect to eventually
3808
merge into trunk but which is not yet ready:
3809
3810
bzr get http://bzr.savannah.gnu.org/r/grub/branches/experimental
3811
3812
Once you have used `bzr get' to fetch an initial copy of a branch,
3813
you can use `bzr pull' to keep it up to date. If you have modified your
3814
local version, you may need to resolve conflicts when pulling.
3815
3816
3817
File: grub.info, Node: Finding your way around, Prev: Getting the source code, Up: Internals
3818
3819
D.2 Finding your way around
3820
===========================
3821
3822
Here is a brief map of the GRUB code base.
3823
3824
GRUB uses Autoconf, but not (yet) Automake. The top-level build
3825
rules are in `configure.ac', `Makefile.in', and `conf/*.rmk'. Each
3826
`conf/*.rmk' file represents a particular target configuration, and is
3827
processed into GNU Make rules by `genmk.rb' (which you only need to
3828
look at if you are extending the build system). If you are adding a new
3829
module which follows an existing pattern, such as a new command or a new
3830
filesystem implementation, it is usually easiest to grep `conf/*.rmk'
3831
for an existing example of that pattern to find out where it should be
3832
added.
3833
3834
Low-level boot code, such as the MBR implementation on PC BIOS
3835
systems, is in the `boot/' directory.
3836
3837
The GRUB kernel is in `kern/'. This contains core facilities such as
3838
the device, disk, and file frameworks, environment variable handling,
3839
list processing, and so on. The kernel should contain enough to get up
3840
to a rescue prompt. Header files for kernel facilities, among others,
3841
are in `include/'.
3842
3843
Terminal implementations are in `term/'.
3844
3845
Disk access code is spread across `disk/' (for accessing the disk
3846
devices themselves), `partmap/' (for interpreting partition table
3847
data), and `fs/' (for accessing filesystems). Note that, with the odd
3848
specialised exception, GRUB only contains code to _read_ from
3849
filesystems and tries to avoid containing any code to _write_ to
3850
filesystems; this lets us confidently assure users that GRUB cannot be
3851
responsible for filesystem corruption.
3852
3853
PCI and USB bus handling is in `bus/'.
3854
3855
Video handling code is in `video/'. The graphical menu system uses
3856
this heavily, but is in a separate directory, `gfxmenu/'.
3857
3858
Most commands are implemented by files in `commands/', with the
3859
following exceptions:
3860
3861
* A few core commands live in `kern/corecmd.c'.
3862
3863
* Commands related to normal mode live under `normal/'.
3864
3865
* Commands that load and boot kernels live under `loader/'.
3866
3867
* The `loopback' command is really a disk device, and so lives in
3868
`disk/loopback.c'.
3869
3870
* The `gettext' command lives under `gettext/'.
3871
3872
* The `loadfont' and `lsfonts' commands live under `font/'.
3873
3874
* The `serial', `terminfo', and `background_image' commands live
3875
under `term/'.
3876
3877
* The `efiemu_*' commands live under `efiemu/'.
3878
3879
There are a few other special-purpose exceptions; grep for them if
3880
they matter to you.
3881
3882
3883
File: grub.info, Node: Copying This Manual, Next: Index, Prev: Internals, Up: Top
3884
3885
Appendix E Copying This Manual
3886
******************************
3887
3888
* Menu:
3889
3890
* GNU Free Documentation License:: License for copying this manual.
3891
3892
3893
File: grub.info, Node: GNU Free Documentation License, Up: Copying This Manual
3894
3895
E.1 GNU Free Documentation License
3896
==================================
3897
3898
Version 1.2, November 2002
3899
3900
Copyright (C) 2000,2001,2002 Free Software Foundation, Inc.
3901
51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
3902
3903
Everyone is permitted to copy and distribute verbatim copies
3904
of this license document, but changing it is not allowed.
3905
3906
0. PREAMBLE
3907
3908
The purpose of this License is to make a manual, textbook, or other
3909
functional and useful document "free" in the sense of freedom: to
3910
assure everyone the effective freedom to copy and redistribute it,
3911
with or without modifying it, either commercially or
3912
noncommercially. Secondarily, this License preserves for the
3913
author and publisher a way to get credit for their work, while not
3914
being considered responsible for modifications made by others.
3915
3916
This License is a kind of "copyleft", which means that derivative
3917
works of the document must themselves be free in the same sense.
3918
It complements the GNU General Public License, which is a copyleft
3919
license designed for free software.
3920
3921
We have designed this License in order to use it for manuals for
3922
free software, because free software needs free documentation: a
3923
free program should come with manuals providing the same freedoms
3924
that the software does. But this License is not limited to
3925
software manuals; it can be used for any textual work, regardless
3926
of subject matter or whether it is published as a printed book.
3927
We recommend this License principally for works whose purpose is
3928
instruction or reference.
3929
3930
1. APPLICABILITY AND DEFINITIONS
3931
3932
This License applies to any manual or other work, in any medium,
3933
that contains a notice placed by the copyright holder saying it
3934
can be distributed under the terms of this License. Such a notice
3935
grants a world-wide, royalty-free license, unlimited in duration,
3936
to use that work under the conditions stated herein. The
3937
"Document", below, refers to any such manual or work. Any member
3938
of the public is a licensee, and is addressed as "you". You
3939
accept the license if you copy, modify or distribute the work in a
3940
way requiring permission under copyright law.
3941
3942
A "Modified Version" of the Document means any work containing the
3943
Document or a portion of it, either copied verbatim, or with
3944
modifications and/or translated into another language.
3945
3946
A "Secondary Section" is a named appendix or a front-matter section
3947
of the Document that deals exclusively with the relationship of the
3948
publishers or authors of the Document to the Document's overall
3949
subject (or to related matters) and contains nothing that could
3950
fall directly within that overall subject. (Thus, if the Document
3951
is in part a textbook of mathematics, a Secondary Section may not
3952
explain any mathematics.) The relationship could be a matter of
3953
historical connection with the subject or with related matters, or
3954
of legal, commercial, philosophical, ethical or political position
3955
regarding them.
3956
3957
The "Invariant Sections" are certain Secondary Sections whose
3958
titles are designated, as being those of Invariant Sections, in
3959
the notice that says that the Document is released under this
3960
License. If a section does not fit the above definition of
3961
Secondary then it is not allowed to be designated as Invariant.
3962
The Document may contain zero Invariant Sections. If the Document
3963
does not identify any Invariant Sections then there are none.
3964
3965
The "Cover Texts" are certain short passages of text that are
3966
listed, as Front-Cover Texts or Back-Cover Texts, in the notice
3967
that says that the Document is released under this License. A
3968
Front-Cover Text may be at most 5 words, and a Back-Cover Text may
3969
be at most 25 words.
3970
3971
A "Transparent" copy of the Document means a machine-readable copy,
3972
represented in a format whose specification is available to the
3973
general public, that is suitable for revising the document
3974
straightforwardly with generic text editors or (for images
3975
composed of pixels) generic paint programs or (for drawings) some
3976
widely available drawing editor, and that is suitable for input to
3977
text formatters or for automatic translation to a variety of
3978
formats suitable for input to text formatters. A copy made in an
3979
otherwise Transparent file format whose markup, or absence of
3980
markup, has been arranged to thwart or discourage subsequent
3981
modification by readers is not Transparent. An image format is
3982
not Transparent if used for any substantial amount of text. A
3983
copy that is not "Transparent" is called "Opaque".
3984
3985
Examples of suitable formats for Transparent copies include plain
3986
ASCII without markup, Texinfo input format, LaTeX input format,
3987
SGML or XML using a publicly available DTD, and
3988
standard-conforming simple HTML, PostScript or PDF designed for
3989
human modification. Examples of transparent image formats include
3990
PNG, XCF and JPG. Opaque formats include proprietary formats that
3991
can be read and edited only by proprietary word processors, SGML or
3992
XML for which the DTD and/or processing tools are not generally
3993
available, and the machine-generated HTML, PostScript or PDF
3994
produced by some word processors for output purposes only.
3995
3996
The "Title Page" means, for a printed book, the title page itself,
3997
plus such following pages as are needed to hold, legibly, the
3998
material this License requires to appear in the title page. For
3999
works in formats which do not have any title page as such, "Title
4000
Page" means the text near the most prominent appearance of the
4001
work's title, preceding the beginning of the body of the text.
4002
4003
A section "Entitled XYZ" means a named subunit of the Document
4004
whose title either is precisely XYZ or contains XYZ in parentheses
4005
following text that translates XYZ in another language. (Here XYZ
4006
stands for a specific section name mentioned below, such as
4007
"Acknowledgements", "Dedications", "Endorsements", or "History".)
4008
To "Preserve the Title" of such a section when you modify the
4009
Document means that it remains a section "Entitled XYZ" according
4010
to this definition.
4011
4012
The Document may include Warranty Disclaimers next to the notice
4013
which states that this License applies to the Document. These
4014
Warranty Disclaimers are considered to be included by reference in
4015
this License, but only as regards disclaiming warranties: any other
4016
implication that these Warranty Disclaimers may have is void and
4017
has no effect on the meaning of this License.
4018
4019
2. VERBATIM COPYING
4020
4021
You may copy and distribute the Document in any medium, either
4022
commercially or noncommercially, provided that this License, the
4023
copyright notices, and the license notice saying this License
4024
applies to the Document are reproduced in all copies, and that you
4025
add no other conditions whatsoever to those of this License. You
4026
may not use technical measures to obstruct or control the reading
4027
or further copying of the copies you make or distribute. However,
4028
you may accept compensation in exchange for copies. If you
4029
distribute a large enough number of copies you must also follow
4030
the conditions in section 3.
4031
4032
You may also lend copies, under the same conditions stated above,
4033
and you may publicly display copies.
4034
4035
3. COPYING IN QUANTITY
4036
4037
If you publish printed copies (or copies in media that commonly
4038
have printed covers) of the Document, numbering more than 100, and
4039
the Document's license notice requires Cover Texts, you must
4040
enclose the copies in covers that carry, clearly and legibly, all
4041
these Cover Texts: Front-Cover Texts on the front cover, and
4042
Back-Cover Texts on the back cover. Both covers must also clearly
4043
and legibly identify you as the publisher of these copies. The
4044
front cover must present the full title with all words of the
4045
title equally prominent and visible. You may add other material
4046
on the covers in addition. Copying with changes limited to the
4047
covers, as long as they preserve the title of the Document and
4048
satisfy these conditions, can be treated as verbatim copying in
4049
other respects.
4050
4051
If the required texts for either cover are too voluminous to fit
4052
legibly, you should put the first ones listed (as many as fit
4053
reasonably) on the actual cover, and continue the rest onto
4054
adjacent pages.
4055
4056
If you publish or distribute Opaque copies of the Document
4057
numbering more than 100, you must either include a
4058
machine-readable Transparent copy along with each Opaque copy, or
4059
state in or with each Opaque copy a computer-network location from
4060
which the general network-using public has access to download
4061
using public-standard network protocols a complete Transparent
4062
copy of the Document, free of added material. If you use the
4063
latter option, you must take reasonably prudent steps, when you
4064
begin distribution of Opaque copies in quantity, to ensure that
4065
this Transparent copy will remain thus accessible at the stated
4066
location until at least one year after the last time you
4067
distribute an Opaque copy (directly or through your agents or
4068
retailers) of that edition to the public.
4069
4070
It is requested, but not required, that you contact the authors of
4071
the Document well before redistributing any large number of
4072
copies, to give them a chance to provide you with an updated
4073
version of the Document.
4074
4075
4. MODIFICATIONS
4076
4077
You may copy and distribute a Modified Version of the Document
4078
under the conditions of sections 2 and 3 above, provided that you
4079
release the Modified Version under precisely this License, with
4080
the Modified Version filling the role of the Document, thus
4081
licensing distribution and modification of the Modified Version to
4082
whoever possesses a copy of it. In addition, you must do these
4083
things in the Modified Version:
4084
4085
A. Use in the Title Page (and on the covers, if any) a title
4086
distinct from that of the Document, and from those of
4087
previous versions (which should, if there were any, be listed
4088
in the History section of the Document). You may use the
4089
same title as a previous version if the original publisher of
4090
that version gives permission.
4091
4092
B. List on the Title Page, as authors, one or more persons or
4093
entities responsible for authorship of the modifications in
4094
the Modified Version, together with at least five of the
4095
principal authors of the Document (all of its principal
4096
authors, if it has fewer than five), unless they release you
4097
from this requirement.
4098
4099
C. State on the Title page the name of the publisher of the
4100
Modified Version, as the publisher.
4101
4102
D. Preserve all the copyright notices of the Document.
4103
4104
E. Add an appropriate copyright notice for your modifications
4105
adjacent to the other copyright notices.
4106
4107
F. Include, immediately after the copyright notices, a license
4108
notice giving the public permission to use the Modified
4109
Version under the terms of this License, in the form shown in
4110
the Addendum below.
4111
4112
G. Preserve in that license notice the full lists of Invariant
4113
Sections and required Cover Texts given in the Document's
4114
license notice.
4115
4116
H. Include an unaltered copy of this License.
4117
4118
I. Preserve the section Entitled "History", Preserve its Title,
4119
and add to it an item stating at least the title, year, new
4120
authors, and publisher of the Modified Version as given on
4121
the Title Page. If there is no section Entitled "History" in
4122
the Document, create one stating the title, year, authors,
4123
and publisher of the Document as given on its Title Page,
4124
then add an item describing the Modified Version as stated in
4125
the previous sentence.
4126
4127
J. Preserve the network location, if any, given in the Document
4128
for public access to a Transparent copy of the Document, and
4129
likewise the network locations given in the Document for
4130
previous versions it was based on. These may be placed in
4131
the "History" section. You may omit a network location for a
4132
work that was published at least four years before the
4133
Document itself, or if the original publisher of the version
4134
it refers to gives permission.
4135
4136
K. For any section Entitled "Acknowledgements" or "Dedications",
4137
Preserve the Title of the section, and preserve in the
4138
section all the substance and tone of each of the contributor
4139
acknowledgements and/or dedications given therein.
4140
4141
L. Preserve all the Invariant Sections of the Document,
4142
unaltered in their text and in their titles. Section numbers
4143
or the equivalent are not considered part of the section
4144
titles.
4145
4146
M. Delete any section Entitled "Endorsements". Such a section
4147
may not be included in the Modified Version.
4148
4149
N. Do not retitle any existing section to be Entitled
4150
"Endorsements" or to conflict in title with any Invariant
4151
Section.
4152
4153
O. Preserve any Warranty Disclaimers.
4154
4155
If the Modified Version includes new front-matter sections or
4156
appendices that qualify as Secondary Sections and contain no
4157
material copied from the Document, you may at your option
4158
designate some or all of these sections as invariant. To do this,
4159
add their titles to the list of Invariant Sections in the Modified
4160
Version's license notice. These titles must be distinct from any
4161
other section titles.
4162
4163
You may add a section Entitled "Endorsements", provided it contains
4164
nothing but endorsements of your Modified Version by various
4165
parties--for example, statements of peer review or that the text
4166
has been approved by an organization as the authoritative
4167
definition of a standard.
4168
4169
You may add a passage of up to five words as a Front-Cover Text,
4170
and a passage of up to 25 words as a Back-Cover Text, to the end
4171
of the list of Cover Texts in the Modified Version. Only one
4172
passage of Front-Cover Text and one of Back-Cover Text may be
4173
added by (or through arrangements made by) any one entity. If the
4174
Document already includes a cover text for the same cover,
4175
previously added by you or by arrangement made by the same entity
4176
you are acting on behalf of, you may not add another; but you may
4177
replace the old one, on explicit permission from the previous
4178
publisher that added the old one.
4179
4180
The author(s) and publisher(s) of the Document do not by this
4181
License give permission to use their names for publicity for or to
4182
assert or imply endorsement of any Modified Version.
4183
4184
5. COMBINING DOCUMENTS
4185
4186
You may combine the Document with other documents released under
4187
this License, under the terms defined in section 4 above for
4188
modified versions, provided that you include in the combination
4189
all of the Invariant Sections of all of the original documents,
4190
unmodified, and list them all as Invariant Sections of your
4191
combined work in its license notice, and that you preserve all
4192
their Warranty Disclaimers.
4193
4194
The combined work need only contain one copy of this License, and
4195
multiple identical Invariant Sections may be replaced with a single
4196
copy. If there are multiple Invariant Sections with the same name
4197
but different contents, make the title of each such section unique
4198
by adding at the end of it, in parentheses, the name of the
4199
original author or publisher of that section if known, or else a
4200
unique number. Make the same adjustment to the section titles in
4201
the list of Invariant Sections in the license notice of the
4202
combined work.
4203
4204
In the combination, you must combine any sections Entitled
4205
"History" in the various original documents, forming one section
4206
Entitled "History"; likewise combine any sections Entitled
4207
"Acknowledgements", and any sections Entitled "Dedications". You
4208
must delete all sections Entitled "Endorsements."
4209
4210
6. COLLECTIONS OF DOCUMENTS
4211
4212
You may make a collection consisting of the Document and other
4213
documents released under this License, and replace the individual
4214
copies of this License in the various documents with a single copy
4215
that is included in the collection, provided that you follow the
4216
rules of this License for verbatim copying of each of the
4217
documents in all other respects.
4218
4219
You may extract a single document from such a collection, and
4220
distribute it individually under this License, provided you insert
4221
a copy of this License into the extracted document, and follow
4222
this License in all other respects regarding verbatim copying of
4223
that document.
4224
4225
7. AGGREGATION WITH INDEPENDENT WORKS
4226
4227
A compilation of the Document or its derivatives with other
4228
separate and independent documents or works, in or on a volume of
4229
a storage or distribution medium, is called an "aggregate" if the
4230
copyright resulting from the compilation is not used to limit the
4231
legal rights of the compilation's users beyond what the individual
4232
works permit. When the Document is included in an aggregate, this
4233
License does not apply to the other works in the aggregate which
4234
are not themselves derivative works of the Document.
4235
4236
If the Cover Text requirement of section 3 is applicable to these
4237
copies of the Document, then if the Document is less than one half
4238
of the entire aggregate, the Document's Cover Texts may be placed
4239
on covers that bracket the Document within the aggregate, or the
4240
electronic equivalent of covers if the Document is in electronic
4241
form. Otherwise they must appear on printed covers that bracket
4242
the whole aggregate.
4243
4244
8. TRANSLATION
4245
4246
Translation is considered a kind of modification, so you may
4247
distribute translations of the Document under the terms of section
4248
4. Replacing Invariant Sections with translations requires special
4249
permission from their copyright holders, but you may include
4250
translations of some or all Invariant Sections in addition to the
4251
original versions of these Invariant Sections. You may include a
4252
translation of this License, and all the license notices in the
4253
Document, and any Warranty Disclaimers, provided that you also
4254
include the original English version of this License and the
4255
original versions of those notices and disclaimers. In case of a
4256
disagreement between the translation and the original version of
4257
this License or a notice or disclaimer, the original version will
4258
prevail.
4259
4260
If a section in the Document is Entitled "Acknowledgements",
4261
"Dedications", or "History", the requirement (section 4) to
4262
Preserve its Title (section 1) will typically require changing the
4263
actual title.
4264
4265
9. TERMINATION
4266
4267
You may not copy, modify, sublicense, or distribute the Document
4268
except as expressly provided for under this License. Any other
4269
attempt to copy, modify, sublicense or distribute the Document is
4270
void, and will automatically terminate your rights under this
4271
License. However, parties who have received copies, or rights,
4272
from you under this License will not have their licenses
4273
terminated so long as such parties remain in full compliance.
4274
4275
10. FUTURE REVISIONS OF THIS LICENSE
4276
4277
The Free Software Foundation may publish new, revised versions of
4278
the GNU Free Documentation License from time to time. Such new
4279
versions will be similar in spirit to the present version, but may
4280
differ in detail to address new problems or concerns. See
4281
`http://www.gnu.org/copyleft/'.
4282
4283
Each version of the License is given a distinguishing version
4284
number. If the Document specifies that a particular numbered
4285
version of this License "or any later version" applies to it, you
4286
have the option of following the terms and conditions either of
4287
that specified version or of any later version that has been
4288
published (not as a draft) by the Free Software Foundation. If
4289
the Document does not specify a version number of this License,
4290
you may choose any version ever published (not as a draft) by the
4291
Free Software Foundation.
4292
4293
E.1.1 ADDENDUM: How to use this License for your documents
4294
----------------------------------------------------------
4295
4296
To use this License in a document you have written, include a copy of
4297
the License in the document and put the following copyright and license
4298
notices just after the title page:
4299
4300
Copyright (C) YEAR YOUR NAME.
4301
Permission is granted to copy, distribute and/or modify this document
4302
under the terms of the GNU Free Documentation License, Version 1.2
4303
or any later version published by the Free Software Foundation;
4304
with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
4305
Texts. A copy of the license is included in the section entitled ``GNU
4306
Free Documentation License''.
4307
4308
If you have Invariant Sections, Front-Cover Texts and Back-Cover
4309
Texts, replace the "with...Texts." line with this:
4310
4311
with the Invariant Sections being LIST THEIR TITLES, with
4312
the Front-Cover Texts being LIST, and with the Back-Cover Texts
4313
being LIST.
4314
4315
If you have Invariant Sections without Cover Texts, or some other
4316
combination of the three, merge those two alternatives to suit the
4317
situation.
4318
4319
If your document contains nontrivial examples of program code, we
4320
recommend releasing these examples in parallel under your choice of
4321
free software license, such as the GNU General Public License, to
4322
permit their use in free software.
4323
4324
4325
File: grub.info, Node: Index, Prev: Copying This Manual, Up: Top
4326
4327
Index
4328
*****
4329
4330
[index ]
4331
* Menu:
4332
4333
* acpi: acpi. (line 11)
4334
* badram: badram. (line 7)
4335
* blocklist: blocklist. (line 7)
4336
* boot: boot. (line 7)
4337
* cat: cat. (line 7)
4338
* chainloader: chainloader. (line 7)
4339
* cmp: cmp. (line 7)
4340
* configfile: configfile. (line 7)
4341
* cpuid: cpuid. (line 7)
4342
* crc: crc. (line 7)
4343
* date: date. (line 7)
4344
* drivemap: drivemap. (line 7)
4345
* echo: echo. (line 7)
4346
* export: export. (line 7)
4347
* FDL, GNU Free Documentation License: GNU Free Documentation License.
4348
(line 6)
4349
* gettext: gettext. (line 7)
4350
* gptsync: gptsync. (line 7)
4351
* halt: halt. (line 7)
4352
* help: help. (line 7)
4353
* initrd: initrd. (line 7)
4354
* initrd16: initrd16. (line 7)
4355
* insmod: insmod. (line 7)
4356
* keystatus: keystatus. (line 7)
4357
* linux: linux. (line 7)
4358
* linux16: linux16. (line 7)
4359
* ls: ls. (line 7)
4360
* menuentry: menuentry. (line 8)
4361
* parttool: parttool. (line 7)
4362
* password: password. (line 7)
4363
* password_pbkdf2: password_pbkdf2. (line 7)
4364
* play: play. (line 7)
4365
* pxe_unload: pxe_unload. (line 7)
4366
* reboot: reboot. (line 7)
4367
* search: search. (line 8)
4368
* sendkey: sendkey. (line 12)
4369
* serial: serial. (line 8)
4370
* set: set. (line 7)
4371
* terminal_input: terminal_input. (line 8)
4372
* terminal_output: terminal_output. (line 8)
4373
* terminfo: terminfo. (line 7)
4374
* unset: unset. (line 7)
4375
4376
4377
4378
Tag Table:
4379
Node: Top893
4380
Node: Introduction3154
4381
Node: Overview3598
4382
Node: Overview-Footnotes5582
4383
Ref: Overview-Footnote-15643
4384
Node: History5804
4385
Node: Changes from GRUB Legacy7892
4386
Node: Features10502
4387
Node: Features-Footnotes16493
4388
Ref: Features-Footnote-116554
4389
Ref: Features-Footnote-216700
4390
Node: Role of a boot loader16845
4391
Node: Role of a boot loader-Footnotes18183
4392
Ref: Role of a boot loader-Footnote-118270
4393
Node: Naming convention18349
4394
Node: Installation21224
4395
Node: Installing GRUB using grub-install22639
4396
Node: Making a GRUB bootable CD-ROM26285
4397
Node: Making a GRUB bootable CD-ROM-Footnotes28349
4398
Ref: Making a GRUB bootable CD-ROM-Footnote-128452
4399
Node: Device map28527
4400
Node: Booting30678
4401
Node: General boot methods31070
4402
Node: Loading an operating system directly31811
4403
Node: Chain-loading32542
4404
Node: OS-specific notes33513
4405
Node: GNU/Hurd33795
4406
Node: GNU/Linux34912
4407
Node: DOS/Windows36535
4408
Node: Configuration38308
4409
Node: Simple configuration38850
4410
Node: Shell-like scripting47178
4411
Node: Shell-like scripting-Footnotes55011
4412
Ref: Shell-like scripting-Footnote-155096
4413
Node: Embedded configuration55223
4414
Node: Theme file format58039
4415
Ref: Pixmap-styled progress bar59462
4416
Ref: Plain progress bar59474
4417
Ref: An example of the slices (in red) used for a terminal window. This drawing was created and sliced in Inkscape_62903
4418
Node: Network77125
4419
Node: Serial terminal79528
4420
Node: Vendor power-on keys81749
4421
Node: Images82710
4422
Node: Filesystem88787
4423
Node: Device syntax89474
4424
Node: File name syntax90966
4425
Node: Block list syntax91720
4426
Node: Interface92453
4427
Node: Command-line interface93272
4428
Node: Command-line interface-Footnotes95213
4429
Ref: Command-line interface-Footnote-195302
4430
Node: Menu interface95397
4431
Node: Menu entry editor96407
4432
Node: Commands97145
4433
Node: Menu-specific commands97872
4434
Node: menuentry98830
4435
Node: General commands99821
4436
Node: serial100317
4437
Node: terminal_input101362
4438
Node: terminal_output102028
4439
Node: terminfo102695
4440
Node: Command-line and menu entry commands103830
4441
Node: acpi106257
4442
Node: badram107296
4443
Node: blocklist108338
4444
Node: boot108572
4445
Node: cat108893
4446
Node: chainloader109528
4447
Node: cmp110150
4448
Node: configfile110701
4449
Node: cpuid111001
4450
Node: crc111466
4451
Node: date111656
4452
Node: drivemap112195
4453
Node: echo112998
4454
Node: export113935
4455
Node: gettext114247
4456
Node: gptsync114654
4457
Node: halt115599
4458
Node: help115925
4459
Node: initrd116388
4460
Node: initrd16116800
4461
Node: insmod117305
4462
Node: keystatus117527
4463
Node: linux118165
4464
Node: linux16119068
4465
Node: ls119776
4466
Node: parttool120322
4467
Node: password121818
4468
Node: password_pbkdf2122100
4469
Node: play122508
4470
Node: pxe_unload123260
4471
Node: reboot123541
4472
Node: search123730
4473
Node: sendkey124506
4474
Node: set130780
4475
Node: unset131079
4476
Node: uppermem131284
4477
Node: Security131485
4478
Node: Supported kernels134173
4479
Node: Troubleshooting141661
4480
Node: GRUB only offers a rescue shell141887
4481
Node: Invoking grub-install144742
4482
Node: Invoking grub-mkconfig145946
4483
Node: Invoking grub-mkpasswd-pbkdf2146583
4484
Node: Obtaining and Building GRUB147246
4485
Node: Reporting bugs148517
4486
Node: Future151321
4487
Node: Internals151811
4488
Node: Getting the source code152016
4489
Node: Finding your way around152890
4490
Node: Copying This Manual155441
4491
Node: GNU Free Documentation License155672
4492
Node: Index178080
4493
4494
End Tag Table
Loggerhead is a web-based interface for Breezy
Version: 2.0.1