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LOADER.CONF(5)		  FreeBSD 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
		   instances 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
		   incorrectly when /etc/fstab is not available	during
		   loader(8) startup (as during	diskless booting from NFS), or
		   if a	different device is desired by the user.  The pre-
		   ferred 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 loaded.

		   Blacklist of	modules.  Modules specified in the blacklist
		   may not be loaded automatically with	a *_load directive,
		   but they may	be loaded directly at the loader(8) prompt.
		   Blacklisted modules may still be loaded indirectly as
		   dependencies	of other modules.

     *_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''
		     selects a mute console (useful for	systems	with neither a
		     video console nor a serial	port), and ``spinconsole''
		     selects the video console which prevents any input	and
		     hides all output replacing	it with	``spinning'' character
		     (useful for embedded products and such).

		     Specify the maximum desired resolution for	the EFI	con-
		     sole.  The	following values are accepted:

		     Value	     Resolution
		     480p	     640x480
		     720p	     1280x720
		     1080p	     1920x1080
		     2160p	     3840x2160
		     4k		     3840x2160
		     5k		     5120x2880
		     WidthxHeight    WidthxHeight

	   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
		     module, making it possible	to display a bmp image on the
		     screen while booting.

		     (``NO'') If set to	``YES'', will load the splash screen
		     module, 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 dis-

		     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	rc.conf(5).

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

		     (``NO'') If set to	``YES'', the microcode update file
		     specified by cpu_microcode_name will be loaded and
		     applied very early	during boot.  This provides function-
		     ality similar to cpucontrol(8) but	ensures	that CPU fea-
		     tures enabled by microcode	updates	can be used by the
		     kernel.  The update will be re-applied automatically when
		     resuming from an ACPI sleep state.	 If the	update file
		     contains updates for multiple processor models, the ker-
		     nel will search for and extract a matching	update.	 Cur-
		     rently this setting is supported only on Intel i386 and
		     amd64 processors.	It has no effect on other processor

		     A path to a microcode update file.

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

		     Specifies a comma-delimited list of FDT overlays to
		     apply.  /boot/dtb/overlays	is created by default for
		     overlays 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 loader.

     /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), cpucontrol(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
     error, so any options which are vital for booting a particular system
     (i.e. ``hw.ata.ata_dma=0'') should	precede	any experimental additions to

FreeBSD	Ports 11.2		October	6, 2018		    FreeBSD Ports 11.2


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