xref: /freebsd/stand/man/boot1.efi.8 (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
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25.Dd April 6, 2021
26.Dt BOOT1.EFI 8
27.Os
28.Sh NAME
29.Nm boot1.efi
30.Nd UEFI chain loader
31.Sh DESCRIPTION
32.Nm
33has been deprecated and will be removed from a future release.
34.Xr loader.efi 8
35handles all its former use cases with more flexibility.
36.Pp
37On UEFI systems,
38.Nm
39loads
40.Pa /boot/loader.efi
41from the default root file system and transfers execution there.
42Some systems may need to use
43.Xr gptboot.efi 8
44when
45.Xr loader.efi 8
46cannot be used directly on the ESP (EFI System Partition).
47.Ss Initialization
48Before looking for the boot device,
49.Nm
50does the following initialization
51.Bl -bullet
52.It
53Sets up the console using the default UEFI console routines.
54.It
55Discovers all possible block devices on the system.
56.It
57Initializes all file system modules to read files from those devices
58.El
59.Ss Boot Device Selection
60.Nm
61uses the following sequence to determine the root file system for
62booting:
63.Bl -bullet
64.It
65If ZFS is configured,
66.Nm
67will search the for zpools that are bootable, preferring the zpool on
68the boot device over the others.
69.It
70If UFS is configured,
71.Nm
72will search all UFS partitions for a bootable partition.
73It will prefer the lowest numbered bootable partition on the boot
74device over all other choices.
75It will fall back to partitions on other devices if none are found.
76.El
77.Pp
78A partition is considered bootable if it can load
79.Pa /boot/loader.efi
80from it.
81Command line arguments to the next boot stage are
82read from the first existing file of
83.Pa /boot.config
84or
85.Pa /boot/config
86in that order.
87.Ss Caveats
88.Bl -bullet
89.It
90The order in which file systems are tried is undefined.
91.It
92No encryption support is available.
93.It
94There's no way to interrupt the boot process to select booting from some
95other location.
96.It
97When configuring a serial console for FreeBSD, but not for UEFI, no output
98will show up on the serial console from boot1.efi.
99.It
100There's no support for marking partitions as the preferred one.
101See
102.Xr gptboot.efi 8 .
103.It
104There's no support for boot-once functionality.
105See
106.Xr gptboot.efi 8 .
107.El
108