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LOADER.CONF(5)		    BSD	File Formats Manual		LOADER.CONF(5)

     loader.conf -- system bootstrap configuration information

     The file loader.conf contains descriptive information on bootstrapping
     the system.  Through it you can specify the kernel	to be booted, parame-
     ters to be	passed to it, and additional modules to	be loaded; and gener-
     ally set all variables described in loader(8).

     Though loader.conf's format was defined explicitly	to resemble
     rc.conf(5), and can be sourced by sh(1), some settings are	treated	in a
     special fashion.  Also, the behavior of some settings is defined by the
     setting's suffix; the prefix identifies which module the setting con-

     The general parsing rules are:

     o	 Spaces	and empty lines	are ignored.

     o	 A # sign will mark the	remainder of the line as a comment.

     o	 Only one setting can be present on each line.

     All settings have the following format:


     Unless it belongs to one of the classes of	settings that receive special
     treatment,	a setting will set the value of	a loader(8) environment	vari-
     able.  The	settings that receive special treatment	are listed below.
     Settings beginning	with "*" below define the modules to be	loaded and may
     have any prefix; the prefix identifies a module.  All such	settings shar-
     ing a common prefix refer to the same module.

     exec	   Immediately executes	a loader(8) command.  This type	of
		   setting cannot be processed by programs other than
		   loader(8), so its use should	be avoided.  Multiple in-
		   stances of it will be processed independently.

		   Defines additional configuration files to be	processed
		   right after the present file.

     kernel	   Name	of the kernel to be loaded.  If	no kernel name is set,
		   no additional modules will be loaded.  The name must	be a
		   subdirectory	of /boot that contains a kernel.

		   Flags to be passed to the kernel.

		   Specify the root partition to mount.	 For example:


		   loader(8) automatically calculates the value	of this	tun-
		   able	from /etc/fstab	from the partition the kernel was
		   loaded from.	 The calculated	value might be calculated in-
		   correctly when /etc/fstab is	not available during loader(8)
		   startup (as during diskless booting from NFS), or if	a dif-
		   ferent device is desired by the user.  The preferred	value
		   can be set in /loader.conf.

		   The value can also be overridden from the loader(8) command
		   line.  This is useful for system recovery when /etc/fstab
		   is damaged, lost, or	read from the wrong partition.

     password	   Protect boot	menu with a password without interrupting
		   autoboot process.  The password should be in	clear text
		   format.  If a password is set, boot menu will not appear
		   until any key is pressed during countdown period specified
		   by autoboot_delay variable or autoboot process fails.  In
		   both	cases user should provide specified password to	be
		   able	to access boot menu.

		   Provides a password to be required by check-password	before
		   execution is	allowed	to continue.  The password should be
		   in clear text format.  If a password	is set,	the user must
		   provide specified password to boot.

		   If set to "YES", module names will be displayed as they are

     *_load	   If set to "YES", that module	will be	loaded.	 If no name is
		   defined (see	below),	the module's name is taken to be the
		   same	as the prefix.

     *_name	   Defines the name of the module.

     *_type	   Defines the module's	type.  If none is given, it defaults
		   to a	kld module.

     *_flags	   Flags and parameters	to be passed to	the module.

     *_before	   Commands to be executed before the module is	loaded.	 Use
		   of this setting should be avoided.

     *_after	   Commands to be executed after the module is loaded.	Use of
		   this	setting	should be avoided.

     *_error	   Commands to be executed if the loading of a module fails.
		   Except for the special value	"abort", which aborts the
		   bootstrap process, use of this setting should be avoided.

     WARNING: developers should	never use these	suffixes for any kernel	envi-
     ronment variables (tunables) or conflicts will result.

     Most of loader.conf's default settings can	be ignored.  The few of	them
     which are important or useful are:

		     ("NO") If set to "YES", a bitmap will be loaded to	be
		     displayed on screen while booting.

		     ("/boot/splash.bmp") Name of the bitmap to	be loaded.
		     Any other name can	be used.

		     ("9600" or	the value of the BOOT_COMCONSOLE_SPEED vari-
		     able when loader(8) was compiled).	 Sets the speed	of the
		     serial console.  If the previous boot loader stage	speci-
		     fied that a serial	console	is in use then the default
		     speed is determined from the current serial port speed

	   console   ("vidconsole") "comconsole" selects serial	console,
		     "vidconsole" selects the video console, "nullconsole" se-
		     lects a mute console (useful for systems with neither a
		     video console nor a serial	port), and "spinconsole" se-
		     lects the video console which prevents any	input and
		     hides all output replacing	it with	"spinning" character
		     (useful for embedded products and such).

	   kernel    ("kernel")

	   kernels   ("kernel kernel.old") Space or comma separated list of
		     kernels to	present	in the boot menu.

		     ("/boot/loader.conf /boot/loader.conf.local")

		     ("NO") If set to "YES", will load the splash screen mod-
		     ule, making it possible to	display	a bmp image on the
		     screen while booting.

		     ("NO") If set to "YES", will load the splash screen mod-
		     ule, making it possible to	display	a pcx image on the
		     screen while booting.

		     ("NO") If set to "YES", the vesa module will be loaded,
		     enabling bitmaps above VGA	resolution to be displayed.

		     If	set to "YES", the beastie boot menu will be skipped.

	   loader_logo ("orbbw")
		     Selects a desired logo in the beastie boot	menu.  Possi-
		     ble values	are: "orbbw", "orb", "fbsdbw", "beastiebw",
		     "beastie",	and "none".

		     If	set to "NO", the beastie boot menu will	be displayed
		     without ANSI coloring.

		     ("YES") If	set to "NO", the very early boot-time entropy
		     file will not be loaded.  See the entropy entries in

		     ("/boot/entropy") The name	of the very early boot-time
		     entropy cache file.

     Other settings that may be	used in	loader.conf that have no default

		     Specifies a comma-delimited list of FDT overlays to ap-
		     ply.  /boot/dtb/overlays is created by default for	over-
		     lays to be	placed in.

		     If	set to "YES", attempt to auto-detect kernels installed
		     in	/boot.	This is	an option specific to the Lua-based
		     loader.  It is not	available in the default Forth-based

     /boot/defaults/loader.conf	 default settings -- do	not change this	file.
     /boot/loader.conf		 user defined settings.
     /boot/loader.conf.local	 machine-specific settings for sites with a
				 common	loader.conf.

     rc.conf(5), boot(8), loader(8), loader.4th(8)

     The file loader.conf first	appeared in FreeBSD 3.2.

     This manual page was written by Daniel C. Sobral <>.

     The loader(8) stops reading loader.conf when it encounters	a syntax er-
     ror, so any options which are vital for booting a particular system (i.e.
     "hw.ata.ata_dma=0") should	precede	any experimental additions to

BSD				March 19, 2018				   BSD


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