LOADER.CONF(5) File Formats and Configurations 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, parameters to
be passed to it, and additional modules to be loaded; and generally set all
variables described in loader(7).

Loader implements set of builtin commands and functions and script
interpreter as standalone binary program. When starting, the loader will
read the file /boot/loader.rc as initialization and startup script, to
include other support files and to read the configuration, describing
current boot environment. All loader scripts and configuration files are
located in the /boot directory tree.

The file /boot/loader.rc must contain the following two lines for
loader.conf to be automatically processed:

include /boot/forth/loader.4th

The default /boot/loader.rc is provided by the operating system and may be
replaced on operating system update. The local updates are advised to be
added into the /boot/loader.rc.local

The configuration variables are read from the following files:

Managed by the eeprom(8) command.

Loader defaults provided by the operating system.

System specific loader configuration. May be provided by the
operating system.

User editable loader configuration.

User editable loader configuration snippets. The files are
processed in lexicographical order. The configuration
snippets mechanism is not available in case of TFTP boot as
TFTP does not provide the directory list.

Configuration file for transient boot. This file is created
by the reboot(8) command and is automatically removed when
system is reaching the multi-user run level.

The configuration is processed in the order listed above.


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(7) environment
variable. 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 sharing
a common prefix refer to the same module.

exec Immediately executes a loader(7) command. This type of
setting cannot be processed by programs other than loader(7),
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.

boot-args Flags to be passed to the kernel.

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.


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

console ("text") "ttya" - "ttyd" selects serial console, "text"
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).

kernel ("i86pc/kernel/${ISADIR}") /platform sub-directory
containing kernel

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

If set to "YES", the beastie boot menu will be skipped.
The beastie boot menu is always skipped if running non-x86

loader_logo ("illumos")
Selects a desired logo in the beastie boot menu. Possible
values depend on distribution; "none" will disable the

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


loader(7), loader.4th(7), boot(8), eeprom(8)


The loader(7) stops reading loader.conf when it encounters a syntax error,
so any options which are vital for booting a particular system should
precede any experimental additions to loader.conf.

illumos November 26, 2017 illumos