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.\" $FreeBSD$
.\"
.Dd December 8, 2017
.Dt EFIBOOTMGR 8
.Os
.Sh NAME
.Nm efibootmgr 
.Nd manipulate the EFI Boot Manager
.Sh SYNOPSIS
.Op Fl aAnNB Ar Bootvar
.Op Fl t Ar timeout
.Op Fl T
.Op Fl o Ar bootorder
.Op Fl verbose
.Op Fl c -k Ar kernel -l Ar loader [-L Ar label] [--dry-run] 
.Sh "DESCRIPTION"
.Nm
manipulates how UEFI Boot Managers boot the system.
Methods of booting can be created and destroyed.
Boot methods can be activated or deactivated.
The order of boot methods tried can be changed.
Temporary boot methods can override the usual booting methods.
.Pp
The UEFI standard defines how hosts may control what is used to
bootstrap the system.
Each method is encapsulated within a persistent UEFI variable, stored
by the UEFI BIOS of the form
.Va BootXXXX .
These variables are numbered, describe where to load the bootstrap
program from, and whether or not the method is active.
The boot order of these methods is controlled by another variable
.Va BootOrder .
The currently booting method is communicated using 
.Va BootCurrent .
A global timeout can also be set.
.Pp
.Nm
requires that the kernel efirt module to get and set these
non-volatile variables.
.Pp
The following options are available:
.Bl -tag -width 28m
.It Fl c Fl -create
Create a new Boot Variable
.It Fl l -loader Ar loader
The path to and name of the loader.
.It Fl k -kernel Ar kernel
The path to and name of the kernel.
.It Fl L -label Ar label
An optional description for the entry.
.It Fl D -dry-run
Process but do not set the given BootVar.
.It Fl B -delete Ar BootVarNum
Delete the given BootVar Num.
.It Fl a -activate Ar BootVarNum
Activate the given BootVarNum.
.It Fl A -deactivate Ar BootVarNum
Deactivate the given BootVarNum.
.It Fl n -bootnext  Ar BootVarNum
Set BootVarNum as the BootNext variable.
.It Fl N -delete-bootnext 
Delete the BootNext optional BootVar.
.It Fl o -bootorder Ar bootorder
Set BootOrder variable to the given comma delimited set of BootVarNums.
The numbers are in hex to match BootXXXX, but may omit leading zeros.
.It Fl t -set-timeout Ar timeout
Set the bootmenu timeout value.
.It Fl T -del-timeout
Delete the BootTimeout variable.
.It Fl v -verbose
Display the device path of BootVars in the output.
.El
.Pp
.Sh Exammples
.Pp
To Display the current Boot related variables in the system:
.Pp
.Dl efibootmgr [-v]
.Pp
This will display the optional BootNext BootVar, BootCurrent,
or currently booted BootVar, followed by the optional Timeout value, any
BootOrder that maybe set, followed finally by all currently defined Boot
variables, active or not. The verbose flag will augment this output with
the hardrive partition uuids, size/offset and device-path of the
variable.
.Pp
The
.Nm
program can be used to create new EFI boot variables. To create a new
boot var pointing to an installation on partition 1 of device ada0 using
the given loader with a description FreeBSD-11: 
.Pp
.Dl efibootmgr -c -d ada0 -p 1 -l/EFI/BOOT/BOOTX64.EFI -L FreeBSD-11
.Pp
This will result in the next available BootVarNum being assigned to a
new UEFI load variable, and given the label "FreeBSD-11" such as:
.Pp
.Dl Boot0009 FreeBSD-11
.Pp
Note newly created BootVars are created inactive. The active state is denoted
by an '*' following the BootVar name in the output.  They are also inserted
into the first position of current BootOrder variable if it exists. They
must first be set to active before being considered available to attempt booting from, else they
are ignored.
.Pp
.Dl efibootmgr -B 0009
.Pp
Will delete the given BootVar Boot0009
.Pp
To set a given newly created BootVar active use:
.Pp
.Dl efibootmgr -a 0009
.Pp
To set a given BootVar to be used as the BootNext variable, irrespective
of its active state, use:
.Pp
.Dl efibootmgr -n 0009
.Pp
To set the BootOrder for the next reboot  use:
.Pp
.Dl efibootmgr -o 0009,0003,...
.Pp
.Sh SEE ALSO
.Xr efivar 8 ,
.Xr uefi 8 ,
.Xr gpart 8