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 December 17, 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 -env 134When creating a 135.Cm Boot 136variable, include a set of environment variables for the loader to set after 137parsing the command line. 138Variables are of the form 139.Dq a=b 140and separated by spaces. 141The argument should be quoted. 142.Nm appends these to the end of the 143.Cm Boot 144environment variable. 145Before processing anything else, 146.Xr loader.efi 8 147will parse this area and set all variables found there. 148.It Fl E -esp 149Print the 150.Fx 151path to the ESP device, derived from the EFI variables 152.Va BootCurrent 153and 154.Va BootXXXX . 155This is the ESP partition used by UEFI to boot the current 156instance of the system. 157If 158.Fl d -device-path 159is specified, the UEFI device path to the ESP is reported instead. 160If 161.Fl p -unix-path 162is specified, the mount point of the ESP is reported instead. 163.It Fl f -fw-ui , Fl F -no-fw-ui 164Set or clear the request to the system firmware to stop in its user 165interface on the next boot. 166.It Fl k -kernel Ar kernel 167The path to and name of the kernel. 168.It Fl l -loader Ar loader 169The path to and name of the loader. 170.It Fl L -label Ar label 171An optional description for the method. 172.It Fl n -bootnext 173Set 174.Ar bootnum 175boot entry as the 176.Cm BootNext 177variable. 178.It Fl N -delete-bootnext 179Delete the 180.Cm BootNext 181optional variable. 182.It Fl o -bootorder Ar bootorder 183Set 184.Cm BootOrder 185variable to the given comma delimited set of 186.Ar bootnum Ns s . 187The numbers are in hex to match 188.Cm Boot Ns Em XXXX , 189but may omit leading zeros. 190.It Fl t -set-timeout Ar timeout 191Set the bootmenu timeout value. 192.It Fl T -del-timeout 193Delete the 194.Cm BootTimeout 195variable. 196.It Fl u -efidev Ar unix-path 197Displays the UEFI device path of 198.Ar unix-path . 199.It Fl v -verbose 200Display the device path of boot entries in the output. 201.El 202.Sh Examples 203To display the current 204.Cm Boot 205related variables in the system: 206.Pp 207.Dl efibootmgr -v 208.Pp 209This will display the optional 210.Cm BootNext 211(if present), 212.Cm BootCurrent 213(currently booted method), followed by the optional 214.Cm Timeout 215value, any 216.Cm BootOrder 217that may be set, followed finally by all currently defined 218.Cm Boot 219variables, active or not. 220The verbose flag, 221.Pq Fl v , 222augments this output with the disk partition uuids, 223size/offset and device-path of the variable. 224The flag will also include any unreferenced (by BootOrder) variables. 225.Pp 226The 227.Nm 228program can be used to create new EFI boot variables. 229The following command may be used to create a new boot method, using 230the EFI partition mounted under 231.Pa /boot/efi , 232mark the method active, using 233the given loader and label the method 234.Qq FreeBSD-15 : 235.Pp 236.Dl efibootmgr -a -c -l /boot/efi/EFI/freebsd/loader.efi -L FreeBSD-15 237.Pp 238This will result in the next available bootnum being assigned to a 239new UEFI boot variable, and given the label 240.Qq FreeBSD-15 241such as: 242.Pp 243.Dl Boot0009 FreeBSD-15 244.Pp 245Note newly created boot entries are, by default, created inactive, hence 246the reason 247.Fl a 248flag is specified above so that it will be considered for booting. 249The active state is denoted by a '*' following the 250.Cm Boot Ns Em XXXX 251name in the output. 252They are also inserted into the first position of current 253.Cm BootOrder 254variable if it exists. 255They must first be set to active before being considered available to attempt 256booting from, else they are ignored. 257.Pp 258.Dl efibootmgr -B -b 0009 259.Pp 260Will delete the given boot entry Boot0009. 261.Pp 262To set the given boot entry active: 263.Pp 264.Dl efibootmgr -a -b 0009 265.Pp 266To set a given boot entry to be used as the 267.Cm BootNext 268variable, irrespective of its active state, use: 269.Pp 270.Dl efibootmgr -n -b 0009 271.Pp 272To set the 273.Cm BootOrder 274for the next reboot use: 275.Pp 276.Dl efibootmgr -o 0009,0003,... 277.Sh SEE ALSO 278.Xr efirt 9 , 279.Xr efivar 8 , 280.Xr gpart 8 , 281.Xr uefi 8 282.Sh STANDARDS 283The Unified Extensible Firmware Interface Specification is available 284from 285.Pa www.uefi.org . 286