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32 .Nd manipulate the EFI Boot Manager
71 program manipulates how UEFI Boot Managers boot the system.
72 It can create and destroy methods for booting along with activating or
74 It can also change the defined order of boot methods.
75 It can create a temporary boot (BootNext) variable that references a
76 boot method to be tried once upon the next boot.
78 The UEFI standard defines how hosts may control what is used to
80 Each method is encapsulated within a persistent UEFI variable, stored
81 by the UEFI BIOS of the form
83 (where XXXX are uppercase hexadecimal digits).
84 These variables are numbered, each describing where to load the bootstrap
85 program from, and whether or not the method is active (used for booting,
86 otherwise the method will be skipped).
87 The order of these methods is controlled by another variable,
89 The currently booted method is communicated using
91 A global timeout can also be set.
94 requires that the kernel module
96 module be present or loaded to get and set these
97 non-volatile variables.
99 The following options are available:
104 boot entry, or the new entry when used with
110 .It Fl b -bootnum Ar bootnum
111 When creating or modifying an entry, use
114 When creating a new entry, fail if it already exists.
122 variable (aka method or entry).
124 Process but do not change any variables.
128 path to the ESP device, derived from the EFI variables
132 This is the ESP partition used by UEFI to boot the current
133 instance of the system.
136 is specified, the UEFI device path to the ESP is reported instead.
139 is specified, the mount point of the ESP is reported instead.
140 .It Fl k -kernel Ar kernel
141 The path to and name of the kernel.
142 .It Fl l -loader Ar loader
143 The path to and name of the loader.
144 .It Fl L -label Ar label
145 An optional description for the method.
152 .It Fl N -delete-bootnext
156 .It Fl o -bootorder Ar bootorder
159 variable to the given comma delimited set of
161 The numbers are in hex to match
162 .Cm Boot Ns Em XXXX ,
163 but may omit leading zeros.
164 .It Fl t -set-timeout Ar timeout
165 Set the bootmenu timeout value.
166 .It Fl T -del-timeout
171 Display the device path of boot entries in the output.
174 To display the current
176 related variables in the system:
180 This will display the optional
184 (currently booted method), followed by the optional
188 that may be set, followed finally by all currently defined
190 variables, active or not.
193 augments this output with the disk partition uuids,
194 size/offset and device-path of the variable.
195 The flag will also include any unreferenced (by BootOrder) variables.
199 program can be used to create new EFI boot variables.
200 The following command may be used to create a new boot method, using
201 the EFI partition mounted under
203 mark the method active, using
204 the given loader and label the method
207 .Dl efibootmgr -a -c -l /mnt/EFI/freebsd/loader.efi -L FreeBSD-11
209 This will result in the next available bootnum being assigned to a
210 new UEFI boot variable, and given the label
214 .Dl Boot0009 FreeBSD-11
216 Note newly created boot entries are, by default, created inactive, hence
219 flag is specified above so that it will be considered for booting.
220 The active state is denoted by a '*' following the
223 They are also inserted into the first position of current
225 variable if it exists.
226 They must first be set to active before being considered available to attempt
227 booting from, else they are ignored.
229 .Dl efibootmgr -B -b 0009
231 Will delete the given boot entry Boot0009.
233 To set the given boot entry active:
235 .Dl efibootmgr -a -b 0009
237 To set a given boot entry to be used as the
239 variable, irrespective of its active state, use:
241 .Dl efibootmgr -n -b 0009
245 for the next reboot use:
247 .Dl efibootmgr -o 0009,0003,...
254 The Unified Extensible Firmware Interface Specification is available