xref: /freebsd/usr.sbin/efibootmgr/efibootmgr.8 (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
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25.Dd February 15, 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.
118.It Fl B -delete
119Delete the given
120.Ar bootnum
121boot entry.
122.It Fl c -create
123Create a new
124.Cm Boot
125variable (aka method or entry).
126.It Fl D -dry-run
127Process but do not change any variables.
128.It Fl E -esp
129Print the
130.Fx
131path to the ESP device, derived from the EFI variables
132.Va BootCurrent
133and
134.Va BootXXXX .
135This is the ESP partition used by UEFI to boot the current
136instance of the system.
137If
138.Fl d -device-path
139is specified, the UEFI device path to the ESP is reported instead.
140If
141.Fl p -unix-path
142is specified, the mount point of the ESP is reported instead.
143.It Fl f -fw-ui , Fl F -no-fw-ui
144Set or clear the request to the system firmware to stop in its user
145interface on the next boot.
146.It Fl k -kernel Ar kernel
147The path to and name of the kernel.
148.It Fl l -loader Ar loader
149The path to and name of the loader.
150.It Fl L -label Ar label
151An optional description for the method.
152.It Fl n -bootnext
153Set
154.Ar bootnum
155boot entry as the
156.Cm BootNext
157variable.
158.It Fl N -delete-bootnext
159Delete the
160.Cm BootNext
161optional variable.
162.It Fl o -bootorder Ar bootorder
163Set
164.Cm BootOrder
165variable to the given comma delimited set of
166.Ar bootnum Ns s .
167The numbers are in hex to match
168.Cm Boot Ns Em XXXX ,
169but may omit leading zeros.
170.It Fl t -set-timeout Ar timeout
171Set the bootmenu timeout value.
172.It Fl T -del-timeout
173Delete the
174.Cm BootTimeout
175variable.
176.It Fl u -efidev Ar unix-path
177Displays the UEFI device path of
178.Ar unix-path .
179.It Fl v -verbose
180Display the device path of boot entries in the output.
181.El
182.Sh Examples
183To display the current
184.Cm Boot
185related variables in the system:
186.Pp
187.Dl efibootmgr -v
188.Pp
189This will display the optional
190.Cm BootNext
191(if present),
192.Cm BootCurrent
193(currently booted method), followed by the optional
194.Cm Timeout
195value, any
196.Cm BootOrder
197that may be set, followed finally by all currently defined
198.Cm Boot
199variables, active or not.
200The verbose flag,
201.Pq Fl v ,
202augments this output with the disk partition uuids,
203size/offset and device-path of the variable.
204The flag will also include any unreferenced (by BootOrder) variables.
205.Pp
206The
207.Nm
208program can be used to create new EFI boot variables.
209The following command may be used to create a new boot method, using
210the EFI partition mounted under
211.Pa /boot/efi ,
212mark the method active, using
213the given loader and label the method
214.Qq FreeBSD-11 :
215.Pp
216.Dl efibootmgr -a -c -l /boot/efi/EFI/freebsd/loader.efi -L FreeBSD-11
217.Pp
218This will result in the next available bootnum being assigned to a
219new UEFI boot variable, and given the label
220.Qq FreeBSD-11
221such as:
222.Pp
223.Dl Boot0009 FreeBSD-11
224.Pp
225Note newly created boot entries are, by default, created inactive, hence
226the reason
227.Fl a
228flag is specified above so that it will be considered for booting.
229The active state is denoted by a '*' following the
230.Cm Boot Ns Em XXXX
231name in the output.
232They are also inserted into the first position of current
233.Cm BootOrder
234variable if it exists.
235They must first be set to active before being considered available to attempt
236booting from, else they are ignored.
237.Pp
238.Dl efibootmgr -B -b 0009
239.Pp
240Will delete the given boot entry Boot0009.
241.Pp
242To set the given boot entry active:
243.Pp
244.Dl efibootmgr -a -b 0009
245.Pp
246To set a given boot entry to be used as the
247.Cm BootNext
248variable, irrespective of its active state, use:
249.Pp
250.Dl efibootmgr -n -b 0009
251.Pp
252To set the
253.Cm BootOrder
254for the next reboot use:
255.Pp
256.Dl efibootmgr -o 0009,0003,...
257.Sh SEE ALSO
258.Xr efirt 9 ,
259.Xr efivar 8 ,
260.Xr gpart 8 ,
261.Xr uefi 8
262.Sh STANDARDS
263The Unified Extensible Firmware Interface Specification is available
264from
265.Pa www.uefi.org .
266