'\" t .TH "LOADER\&.CONF" "5" "" "systemd 251" "loader.conf" .\" ----------------------------------------------------------------- .\" * Define some portability stuff .\" ----------------------------------------------------------------- .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .\" http://bugs.debian.org/507673 .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" ----------------------------------------------------------------- .\" * set default formatting .\" ----------------------------------------------------------------- .\" disable hyphenation .nh .\" disable justification (adjust text to left margin only) .ad l .\" ----------------------------------------------------------------- .\" * MAIN CONTENT STARTS HERE * .\" ----------------------------------------------------------------- .SH "NAME" loader.conf \- Configuration file for systemd\-boot .SH "SYNOPSIS" .PP \fIESP\fR/loader/loader\&.conf, \fIESP\fR/loader/entries/*\&.conf \fIXBOOTLDR\fR/loader/entries/*\&.conf .SH "DESCRIPTION" .PP \fBsystemd-boot\fR(7) will read \fIESP\fR/loader/loader\&.conf, and any files with the "\&.conf" extension under \fIESP\fR/loader/entries/ on the EFI system partition (ESP), and \fIXBOOTLDR\fR/loader/entries/ on the extended boot loader partition (XBOOTLDR) as defined by \m[blue]\fBBoot Loader Specification\fR\m[]\&\s-2\u[1]\d\s+2\&. .PP Each of these configuration files must consist of series of newline (i\&.e\&. ASCII code 10) separated lines, each consisting of an option name, followed by whitespace, and the option value\&. "#" may be used to start a comment line\&. Empty and comment lines are ignored\&. The files use UTF\-8 encoding\&. .PP Boolean arguments may be written as "yes"/"y"/"true"/"t"/"on"/"1" or "no"/"n"/"false"/"f"/"off"/"0"\&. .SH "OPTIONS" .PP The configuration options supported by \fIESP\fR/loader/entries/*\&.conf and \fIXBOOTLDR\fR/loader/entries/*\&.conf files are defined as part of the \m[blue]\fBBoot Loader Specification\fR\m[]\&\s-2\u[1]\d\s+2\&. .PP The following configuration are supported by the loader\&.conf configuration file: .PP default .RS 4 A glob pattern to select the default entry\&. The default entry may be changed in the boot menu itself, in which case the name of the selected entry will be stored as an EFI variable, overriding this option\&. .sp If set to "@saved" the chosen entry will be saved as an EFI variable on every boot and automatically selected the next time the boot loader starts\&. .sp .it 1 an-trap .nr an-no-space-flag 1 .nr an-break-flag 1 .br .B Table\ \&1.\ \&Automatically detected entries will use the following names: .TS allbox tab(:); lB lB. T{ Name T}:T{ Description T} .T& l l l l l l l l l l. T{ auto\-efi\-default T}:T{ EFI Default Loader T} T{ auto\-efi\-shell T}:T{ EFI Shell T} T{ auto\-osx T}:T{ macOS T} T{ auto\-reboot\-to\-firmware\-setup T}:T{ Reboot Into Firmware Interface T} T{ auto\-windows T}:T{ Windows Boot Manager T} .TE .sp 1 .RE .PP timeout .RS 4 How long the boot menu should be shown before the default entry is booted, in seconds\&. This may be changed in the boot menu itself and will be stored as an EFI variable in that case, overriding this option\&. .sp If set to "menu\-hidden" or "0" no menu is shown and the default entry will be booted immediately\&. The menu can be shown by pressing and holding a key before systemd\-boot is launched\&. Setting this to "menu\-force" disables the timeout while always showing the menu\&. .RE .PP console\-mode .RS 4 This option configures the resolution of the console\&. Takes a number or one of the special values listed below\&. The following values may be used: .PP 0 .RS 4 Standard UEFI 80x25 mode .RE .PP 1 .RS 4 80x50 mode, not supported by all devices .RE .PP 2 .RS 4 the first non\-standard mode provided by the device firmware, if any .RE .PP auto .RS 4 Pick a suitable mode automatically using heuristics .RE .PP max .RS 4 Pick the highest\-numbered available mode .RE .PP keep .RS 4 Keep the mode selected by firmware (the default) .RE .RE .PP editor .RS 4 Takes a boolean argument\&. Enable (the default) or disable the editor\&. The editor should be disabled if the machine can be accessed by unauthorized persons\&. .RE .PP auto\-entries .RS 4 Takes a boolean argument\&. Enable (the default) or disable entries for other boot entries found on the boot partition\&. In particular, this may be useful when loader entries are created to show replacement descriptions for those entries\&. .RE .PP auto\-firmware .RS 4 A boolean controlling the presence of the "Reboot into firmware" entry (enabled by default)\&. If this is disabled, the firmware interface may still be reached by using the f key\&. .RE .PP beep .RS 4 Beep n times when the n\-th entry in the boot menu is shown (default disabled)\&. Currently, only x86 is supported, where it uses the PC speaker\&. .RE .PP reboot\-for\-bitlocker .RS 4 Caveat: This feature is experimental, and is likely to be changed (or removed in its current form) in a future version of systemd\&. .sp Work around BitLocker requiring a recovery key when the boot loader was updated (disabled by default)\&. .sp Try to detect BitLocker encrypted drives along with an active TPM\&. If both are found and Windows Boot Manager is selected in the boot menu, set the "BootNext" EFI variable and restart the system\&. The firmware will then start Windows Boot Manager directly, leaving the TPM PCRs in expected states so that Windows can unseal the encryption key\&. This allows systemd\-boot to be updated without having to provide the recovery key for BitLocker drive unlocking\&. .sp Note that the PCRs that Windows uses can be configured with the "Configure TPM platform validation profile for native UEFI firmware configurations" group policy under "Computer Configuration\eAdministrative Templates\eWindows Components\eBitLocker Drive Encryption"\&. When secure boot is enabled, changing this to PCRs "0,2,7,11" should be safe\&. The TPM key protector needs to be removed and then added back for the PCRs on an already encrypted drive to change\&. If PCR 4 is not measured, this setting can be disabled to speed up booting into Windows\&. .RE .PP random\-seed\-mode .RS 4 Takes one of "off", "with\-system\-token" and "always"\&. If "off" no random seed data is read off the ESP, nor passed to the OS\&. If "with\-system\-token" (the default) \fBsystemd\-boot\fR will read a random seed from the ESP (from the file /loader/random\-seed) only if the \fILoaderSystemToken\fR EFI variable is set, and then derive the random seed to pass to the OS from the combination\&. If "always" the boot loader will do so even if \fILoaderSystemToken\fR is not set\&. This mode is useful in environments where protection against OS image reuse is not a concern, and the random seed shall be used even with no further setup in place\&. Use \fBbootctl random\-seed\fR to initialize both the random seed file in the ESP and the system token EFI variable\&. .sp See \m[blue]\fBRandom Seeds\fR\m[]\&\s-2\u[2]\d\s+2 for further information\&. .RE .SH "EXAMPLE" .sp .if n \{\ .RS 4 .\} .nf # /boot/efi/loader/loader\&.conf timeout 0 default 01234567890abcdef1234567890abdf0\-* editor no .fi .if n \{\ .RE .\} .PP The menu will not be shown by default (the menu can still be shown by pressing and holding a key during boot)\&. One of the entries with files with a name starting with "01234567890abcdef1234567890abdf0\-" will be selected by default\&. If more than one entry matches, the one with the highest priority will be selected (generally the one with the highest version number)\&. The editor will be disabled, so it is not possible to alter the kernel command line\&. .SH "SEE ALSO" .PP \fBsystemd-boot\fR(7), \fBbootctl\fR(1) .SH "NOTES" .IP " 1." 4 Boot Loader Specification .RS 4 \%https://systemd.io/BOOT_LOADER_SPECIFICATION .RE .IP " 2." 4 Random Seeds .RS 4 \%https://systemd.io/RANDOM_SEEDS .RE