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

NAME
       loader.conf -- system bootstrap configuration information

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

SYNTAX
       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-
       trols.

       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:

	     variable="value"

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

       autoboot_delay
		     Delay in seconds before automatically  booting.   A  user
		     with  console  access  will  be  able  to	interrupt  the
		     autoboot process and escape into the interactive mode  by
		     pressing a	key on the console during this delay.

		     If	 set  to  "NO",	no autoboot is automatically attempted
		     after   processing	  /boot/loader.rc,   though   explicit
		     autoboot's	 are processed normally, using a 10 second de-
		     lay.

		     If	set to "0", no delay is	inserted, but any keys pressed
		     while the kernel and modules are loaded will enter	inter-
		     active mode.

		     If	set to "-1", no	delay will be inserted and loader.conf
		     starts interactive	mode only if autoboot has failed.   In
		     combination  with the beastie_disable option, this	option
		     prevents users with console access	from being able	to in-
		     terrupt the autoboot process and  escape  to  the	loader
		     prompt.  To use the autoboot_delay	option in this manner,
		     beastie_disable must be set to "YES".

       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.

       loader_conf_dirs
		     Space separated list of directories to process  for  con-
		     figuration	 files.	  The  lua-based  loader  will process
		     files with	a ".conf" suffix that are placed in these  di-
		     rectories.

       loader_conf_files
		     Defines  additional  configuration	 files to be processed
		     right after the present file.   loader_conf_files	should
		     be	treated	as write-only.	One cannot depend on any value
		     remaining	in the loader environment or carried over into
		     the kernel	environment.

       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.

       kernel_options
		     Flags to be passed	to the kernel.

       vfs.root.mountfrom
		     Specify the root partition	to mount.  For example:

			   vfs.root.mountfrom="ufs:/dev/da0s1a"

		     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
		     preferred value can be set	in /loader.conf.

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

       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	speci-
		     fied  by  autoboot_delay  variable	 or  autoboot  process
		     fails.  In	both cases user	should provide specified pass-
		     word to be	able to	access boot menu.

       bootlock_password
		     Provides a	password to be required	by check-password  be-
		     fore  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.

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

       module_blacklist
		     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 de-
		     pendencies	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  en-
       vironment variables (tunables) or conflicts will	result.

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

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

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

	     comconsole_speed
		       ("115200"  or  the  value  of the BOOT_COMCONSOLE_SPEED
		       variable	when loader(8) was compiled).  Sets the	 speed
		       of  the	serial	console.   If the previous boot	loader
		       stage specified that a serial console is	 in  use  then
		       the default speed is determined from the	current	serial
		       port speed setting.

	     console   ("vidconsole")  "comconsole"  selects  serial  console,
		       "vidconsole" selects the	video console,	"efi"  selects
		       the  EFI	 console, "nullconsole"	selects	a mute console
		       (useful for systems with	neither	a video	console	nor  a
		       serial  port), and "spinconsole"	selects	the video con-
		       sole which prevents any input and hides all output  re-
		       placing it with "spinning" character (useful for	embed-
		       ded products and	such).

	     screen.font
		       Set  font size for framebuffer mode.  Default font size
		       is selected based on screen resolution, to achieve ter-
		       minal dimensions	80x24.

	     screen.textmode
		       Value "0" will trigger BIOS loader  to  switch  to  use
		       VESA  BIOS  Extension  (VBE) frame buffer mode for con-
		       sole.  The same	effect	can  be	 achieved  by  setting
		       vbe_max_resolution.

		       Value "1" will force BIOS loader	to use VGA text	mode.

		       If  vbe_max_resolution  is not set, the loader will try
		       to set screen resolution	based on EDID information.  If
		       EDID  is	 not  available,  the  default	resolution  is
		       800x600 (if available).

	     screen.height

	     screen.width

	     screen.depth
		       screen.height,  screen.width,  screen.depth  are	set by
		       loader when loader is using framebuffer	mode  to  draw
		       the screen.

	     efi_max_resolution

	     vbe_max_resolution
		       Specify	the  maximum desired resolution	for the	EFI or
		       VBE framebuffer console.	 The following values are  ac-
		       cepted:

		       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.

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

	     loader_conf_dirs
		       ("/boot/loader.conf.d")

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

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

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

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

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

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

	     entropy_cache_load
		       ("YES") If set to "NO", the very	 early	boot-time  en-
		       tropy file will not be loaded.  See the entropy entries
		       in rc.conf(5).

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

	     cpu_microcode_load
		       ("NO") If set to	"YES", the microcode update file spec-
		       ified by	cpu_microcode_name will	be loaded and  applied
		       very  early  during  boot.  This	provides functionality
		       similar to cpucontrol(8)	but ensures that CPU  features
		       enabled by microcode updates can	be used	by the kernel.
		       The update will be re-applied automatically when	resum-
		       ing  from an ACPI sleep state.  If the update file con-
		       tains updates for multiple processor models, the	kernel
		       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
		       types.

	     cpu_microcode_name
		       A path to a microcode update file.

OTHER SETTINGS
       Other settings that may be used in loader.conf  that  have  no  default
       value:

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

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

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

SEE ALSO
       loader.conf.lua(5),   rc.conf(5),  boot(8),  cpucontrol(8),  loader(8),
       loader.4th(8)

HISTORY
       The file	loader.conf first appeared in FreeBSD 3.2.

AUTHORS
       This manual page	was written by Daniel C. Sobral	<dcs@FreeBSD.org>.

BUGS
       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
       loader.conf.

FreeBSD	13.2			 July 31, 2021			LOADER.CONF(5)

NAME | DESCRIPTION | SYNTAX | DEFAULT SETTINGS | OTHER SETTINGS | FILES | SEE ALSO | HISTORY | AUTHORS | BUGS

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