sysconf-loader(8)

sysconf-loader8

Configure boot loader directives

Usage

sysconf loader [-AcDeFinNqvVx] [{-j jail | -R dir}] [-f file] name [[{+ | -}] =value] ...

sysconf loader [-ADeFnNqvV] [-f file] -a

sysconf loader [-AaDinNq] -d [name ...]

sysconf {loader [-E] -l | -L}

Overview

The loader target of sysconf(8) reads and modifies loader.conf(5) configuration. Shared assignment syntax and options are documented in sysconf(8); multi-file write policy in sysconf-targets(8).

The file list is not hardcoded: just as the boot loader itself hardcodes only /boot/defaults/loader.conf, sysconf names that defaults file and the loader_conf_files, loader_conf_dirs, and local_loader_conf_files directives so that discovery matches the loader (see bsdconf_format(3) and loader.conf(5)). On a stock system this resolves to /boot/device.hints, /boot/loader.conf, /boot/loader.conf.d/*.conf, and /boot/loader.conf.local, in that order; when the defaults file is missing, that stock list is assumed.

Values written for this target are always enclosed in quotes (quoted or unquoted input is accepted) with no whitespace around the equals sign, as demanded by the boot loader's reader.

The defaults file /boot/defaults/loader.conf (or LOADER_DEFAULTS) additionally supports -d, -D, and -A (see sysconf-targets(8)). Space-separated list directives such as kernels use name+=word and name-=word as described in sysconf(8).

Environment

LOADER_DEFAULTS

Defaults file consulted in place of /boot/defaults/loader.conf for file-list discovery and for -d, -D, and -A( in the vein of RC_DEFAULTS in sysrc(8)). The value is used verbatim (not subject to -R).

Files

/boot/defaults/loader.conf

Defaults and the authority on the file list.

/boot/device.hints

First in the stock loader_conf_files list.

/boot/loader.conf

Stock write target.

/boot/loader.conf.d/

Drop-in directory.

/boot/loader.conf.local

Site-local overrides, sourced last.

Examples

sysconf loader zfs_load
sysconf loader zfs_load="YES"
sysconf loader -l
sysconf loader -d verbose_loading
sysconf loader -Ad
sysconf loader -D verbose_loading
sysconf loader -aD
sysconf loader -A
sysconf loader kernels+=kernel_test
sysconf loader kernels-=kernel_test
sysconf -a loader
sysconf loader -f /tmp/loader.conf.new zfs_load="YES"

History

The sysconf utility first appeared in FreeBSD 16.0.

Authors

Devin Teske ⟨[email protected]⟩ Faraz Vahedi ⟨[email protected]⟩

From base 16.0-CURRENT-20261027-61c70dc16a79 in FreeBSD 16.0-CURRENT (2026-10-27). Parsed by carta from the page's mdoc source.