1.\" 2.\" Copyright (c) 2017-2018 Netflix, Inc. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.Dd October 26, 2023 26.Dt EFIBOOTMGR 8 27.Os 28.Sh NAME 29.Nm efibootmgr 30.Nd manipulate the EFI Boot Manager 31.Sh SYNOPSIS 32.Nm 33.Op Fl v 34.Nm 35.Fl a 36.Fl b Ar bootnum 37.Nm 38.Fl A 39.Fl b Ar bootnum 40.Nm 41.Fl B 42.Fl b Ar bootnum 43.Nm 44.Fl c 45.Fl l Ar loader 46.Op Fl aD 47.Op Fl b Ar bootnum 48.Op Fl k Ar kernel 49.Op Fl L Ar label 50.Op Fl e Ar env 51.Nm 52.Fl E 53.Op Fl d 54.Op Fl p 55.Nm 56.Fl F 57.Nm 58.Fl f 59.Nm 60.Fl n 61.Fl b Ar bootnum 62.Nm 63.Fl N 64.Nm 65.Fl o Ar bootorder 66.Nm 67.Fl t Ar timeout 68.Nm 69.Fl T 70.Nm Fl u Ar unix-path 71.Sh "DESCRIPTION" 72The 73.Nm 74program manipulates how UEFI Boot Managers boot the system. 75It can create and destroy methods for booting along with activating or 76deactivating them. 77It can also change the defined order of boot methods. 78It can create a temporary boot (BootNext) variable that references a 79boot method to be tried once upon the next boot. 80.Pp 81The UEFI standard defines how hosts may control what is used to 82bootstrap the system. 83Each method is encapsulated within a persistent UEFI variable, stored 84by the UEFI BIOS of the form 85.Cm Boot Ns Em XXXX 86(where XXXX are uppercase hexadecimal digits). 87These variables are numbered, each describing where to load the bootstrap 88program from, and whether or not the method is active (used for booting, 89otherwise the method will be skipped). 90The order of these methods is controlled by another variable, 91.Cm BootOrder . 92The currently booted method is communicated using 93.Cm BootCurrent . 94A global timeout can also be set. 95.Pp 96.Nm 97requires that the kernel module 98.Xr efirt 9 99module be present or loaded to get and set these 100non-volatile variables. 101.Pp 102The following options are available: 103.Bl -tag -width Ds 104.It Fl a -activate 105Activate the given 106.Ar bootnum 107boot entry, or the new entry when used with 108.Fl c . 109.It Fl A -deactivate 110Deactivate the given 111.Ar bootnum 112boot entry. 113.It Fl b -bootnum Ar bootnum 114When creating or modifying an entry, use 115.Ar bootnum 116as the index. 117When creating a new entry, fail if it already exists. 118For convenience, if 119.Ar bootnum 120is prefixed with 121.Dq boot , 122that prefix is ignored. 123.It Fl B -delete 124Delete the given 125.Ar bootnum 126boot entry. 127.It Fl c -create 128Create a new 129.Cm Boot 130variable (aka method or entry). 131.It Fl D -dry-run 132Process but do not change any variables. 133.It Fl E -esp 134Print the 135.Fx 136path to the ESP device, derived from the EFI variables 137.Va BootCurrent 138and 139.Va BootXXXX . 140This is the ESP partition used by UEFI to boot the current 141instance of the system. 142If 143.Fl d -device-path 144is specified, the UEFI device path to the ESP is reported instead. 145If 146.Fl p -unix-path 147is specified, the mount point of the ESP is reported instead. 148.It Fl f -fw-ui , Fl F -no-fw-ui 149Set or clear the request to the system firmware to stop in its user 150interface on the next boot. 151.It Fl k -kernel Ar kernel 152The path to and name of the kernel. 153.It Fl l -loader Ar loader 154The path to and name of the loader. 155.It Fl L -label Ar label 156An optional description for the method. 157.It Fl n -bootnext 158Set 159.Ar bootnum 160boot entry as the 161.Cm BootNext 162variable. 163.It Fl N -delete-bootnext 164Delete the 165.Cm BootNext 166optional variable. 167.It Fl o -bootorder Ar bootorder 168Set 169.Cm BootOrder 170variable to the given comma delimited set of 171.Ar bootnum Ns s . 172The numbers are in hex to match 173.Cm Boot Ns Em XXXX , 174but may omit leading zeros. 175.It Fl t -set-timeout Ar timeout 176Set the bootmenu timeout value. 177.It Fl T -del-timeout 178Delete the 179.Cm BootTimeout 180variable. 181.It Fl u -efidev Ar unix-path 182Displays the UEFI device path of 183.Ar unix-path . 184.It Fl v -verbose 185Display the device path of boot entries in the output. 186.El 187.Sh Examples 188To display the current 189.Cm Boot 190related variables in the system: 191.Pp 192.Dl efibootmgr -v 193.Pp 194This will display the optional 195.Cm BootNext 196(if present), 197.Cm BootCurrent 198(currently booted method), followed by the optional 199.Cm Timeout 200value, any 201.Cm BootOrder 202that may be set, followed finally by all currently defined 203.Cm Boot 204variables, active or not. 205The verbose flag, 206.Pq Fl v , 207augments this output with the disk partition uuids, 208size/offset and device-path of the variable. 209The flag will also include any unreferenced (by BootOrder) variables. 210.Pp 211The 212.Nm 213program can be used to create new EFI boot variables. 214The following command may be used to create a new boot method, using 215the EFI partition mounted under 216.Pa /boot/efi , 217mark the method active, using 218the given loader and label the method 219.Qq FreeBSD-11 : 220.Pp 221.Dl efibootmgr -a -c -l /boot/efi/EFI/freebsd/loader.efi -L FreeBSD-11 222.Pp 223This will result in the next available bootnum being assigned to a 224new UEFI boot variable, and given the label 225.Qq FreeBSD-11 226such as: 227.Pp 228.Dl Boot0009 FreeBSD-11 229.Pp 230Note newly created boot entries are, by default, created inactive, hence 231the reason 232.Fl a 233flag is specified above so that it will be considered for booting. 234The active state is denoted by a '*' following the 235.Cm Boot Ns Em XXXX 236name in the output. 237They are also inserted into the first position of current 238.Cm BootOrder 239variable if it exists. 240They must first be set to active before being considered available to attempt 241booting from, else they are ignored. 242.Pp 243.Dl efibootmgr -B -b 0009 244.Pp 245Will delete the given boot entry Boot0009. 246.Pp 247To set the given boot entry active: 248.Pp 249.Dl efibootmgr -a -b 0009 250.Pp 251To set a given boot entry to be used as the 252.Cm BootNext 253variable, irrespective of its active state, use: 254.Pp 255.Dl efibootmgr -n -b 0009 256.Pp 257To set the 258.Cm BootOrder 259for the next reboot use: 260.Pp 261.Dl efibootmgr -o 0009,0003,... 262.Sh SEE ALSO 263.Xr efirt 9 , 264.Xr efivar 8 , 265.Xr gpart 8 , 266.Xr uefi 8 267.Sh STANDARDS 268The Unified Extensible Firmware Interface Specification is available 269from 270.Pa www.uefi.org . 271