Difference between revisions of "Systemd-boot"
(→Adding boot entries: too many backslashes)
m (→Adding boot entries: just use forward slashes)
|Line 73:||Line 73:|
title Arch Linux (Encrypted)
title Arch Linux (Encrypted)
options initrd=pathtoinitramfs-linux.img cryptdevice=UUID=<UUID>:luks-<UUID> root=UUID=<luks-UUID> rw
Revision as of 22:20, 7 January 2014
$espdenotes the mountpoint of the EFI System Partition aka ESP.
Installand install gummiboot in ESP:
# mount -t efivarfs efivarfs /sys/firmware/efi/efivars # required even inside chroot if any, ignore if already mounted # pacman -S gummiboot # gummiboot --path=$esp install
This will automatically copy the gummiboot binary to your EFI System Partition and create a boot entry in the EFI Boot Manager. If you are not booted via EFI, creating the boot entry will fail. You should however still be able to boot gummiboot as it copies the binary to the default EFI binary location on your ESP (
$esp/EFI/boot/bootx64.efi on x64 systems) (unless a non-gummiboot
$esp/EFI/boot/bootx64.efi is already present).
- The gummiboot command by default assumes that your EFI System Partition is mounted on
/boot. This means gummiboot in the ESP will not be updated automatically during pkg updates and you will have to call
gummiboot --path=$esp updateafter every package update. Additionally you will have to make sure that the kernel and initramfs are copied onto the ESP as gummiboot cannot load EFI binaries from other partitions. It is therefore strongly recommended to mount your ESP to
/bootif you use gummiboot, in which case updating will happen automatically by the post_install script of during package updates.
gummibootfails to create a boot entry, check whether all the conditions mentioned here are met.
The basic configuration is kept in
$esp/loader/loader.conf, with just two possible configuration options:
default– default entry to select (without the
.confsuffix); can be a wildcard like
timeout– menu timeout in seconds. If this is not set, the menu will only be shown when you hold the space key while booting.
default arch timeout 4
Note that both options can be changed in the boot menu itself, which will store them as EFI variables.
Adding boot entries
Gummiboot searches for boot menu items in
$esp/loader/entries/*.conf – each file found must contain exactly one boot entry. The possible options are:
title– operating system name. Required.
version– kernel version, shown only when multiple entries with same title exist. Optional.
machine-id– machine identifier from
/etc/machine-id, shown only when multiple entries with same title and version exist. Optional.
efi– EFI program to start, relative to your ESP (
/vmlinuz-linux. Either this or
linux(see below) is required.
options– Command-line options to pass to the EFI program. Optional, but you will need at least
root=devif booting Linux.
For Linux, you can specify
linux path-to-vmlinuz and
initrd path-to-initramfs; this will be automatically translated to
efi path and
options initrd=path – this syntax is only supported for convenience and has no differences in function.
An example entry for Arch Linux:
title Arch Linux linux /vmlinuz-linux initrd /initramfs-linux.img options root=PARTUUID=14420948-2cea-4de7-b042-40f67c618660 rw
Please note in the example above that PARTUUID/PARTLABEL identifies a GPT partition, and differs from UUID/LABEL, which identifies a filesystem. Using the PARTUUID/PARTLABEL is advantageous because it is invariant if you reformat the partition with another filesystem. It is also useful if you do not have a filesystem on the partition (or use LUKS, which does not support LABELs).
An example entry for encrypted root (dm-crypt with LUKS)
title Arch Linux (Encrypted) linux /path/to/vmlinuz-linux options initrd=/path/to/initramfs-linux.img cryptdevice=UUID=<UUID>:luks-<UUID> root=UUID=<luks-UUID> rw
In the encrypted example, not that the initrd is in options -- this does not appear to be discretionary at this time. Note that UUID is used for in this example. PARTUUID should be able to replace the UUID, if so desired.
You can also add other EFI programs such as
\EFI\Microsoft\Boot\Bootmgfw.efi), "EFI Shell" (
\shellx64.efi) and "EFI Default Loader" (
\EFI\Boot\bootx64.efi), and display entries for them if they are present, so you do not have to manually create entries for them. However it does not autodetect other EFI applications (unlike rEFInd), so for booting the kernel, manual config entries must be created as mentioned above.
The following keys are used inside the menu:
Up/Down- select entry
Enter- boot the selected entry
d- select the default entry to boot (stored in a non-volatile EFI variable)
-/T- decrease the timeout (stored in a non-volatile EFI variable)
+/t- increase the timeout (stored in a non-volatile EFI variable)
e- edit the kernel command line
v- show the gummiboot and UEFI version
P- print the current configuration
These hotkeys will, when pressed inside the menu or during bootup, directly boot a specific entry:
a- OS X
s- EFI Shell
1-9- number of entry
Manual entry using efibootmgr
gummiboot install command failed, you can create a EFI boot entry manually using
# efibootmgr -c -d /dev/sdX -p Y -l /EFI/gummiboot/gummibootx64.efi -L "Gummiboot"
/dev/sdXY is the EFISYS partition.