I just installed (one more time) my laptop and this time, I switch from GRUB to systemd-boot. I prevent you that all commands that I gonna show you are used for an Arch Linux installation. They may work for you, but refers you to the documentation of your distribution before begin.
So, we can start now.
Set up
The configuration of my laptop is pretty simple, there are 2 OS, one is Microsoft Windows and the other one is Arch Linux. I first installed Windows, it is easier because it creates what it need on an empty disk. After that I set up my Linux to the installation step of the bootloader. Futhermore, all are in only one solid state drive that is cut like this :
$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 931,5G 0 disk
├─sda1 8:1 0 450M 0 part
├─sda2 8:2 0 100M 0 part /boot/efi
├─sda3 8:3 0 16M 0 part
├─sda4 8:4 0 128G 0 part
├─sda5 8:5 0 600G 0 part /home
├─sda6 8:6 0 3G 0 part /boot
└─sda7 8:7 0 200G 0 part /
Tips: I used the lsblk command to display information about my SSD’s partitions.
From here, we can see that Windows has 4 partitions that are /dev/sda1, /dev/sda2, /dev/sda3 and /dev/sda4 and Arch Linux got 3 partitions /dev/sda5, /dev/sda6, /dev/sd7 and share one with Windows which is /dev/sda2.
Now, take a look of the file-system of each that is pretty important for next movements.
$ lsblk -fs
sda1 ntfs Récupération <uuid>
└─sda
sda2 vfat <uuid> /boot/efi
└─sda
sda3
└─sda
sda4 ntfs OS 10 <uuid>
└─sda
sda5 btrfs <uuid> /home
└─sda
sda6 btrfs <uuid> /boot
└─sda
sda7 btrfs <uuid> /
Tips: I used lsblk as well to show me file-system encoding with the -fs option.
As we can observe, all my Linux system partitions are based on the btrfs except the /dev/sda2 partition that is the partition known as ESP, I will explain this later and my Windows system use vfat (aka fat32) and ntfs. I do not wanna that my ESP partition will be /boot, I prefer to see it on /boot/efi I thinks that is more revelant and reliable.
ESP? What is it?
ESP is an acronym which mean EFI System Partition and that is on this partition we need to install the Linux bootloader to take care about others operating systems and our Linux. Furthermore, this partition must be in fat32 because your bios need to read it, in order to boot on the selected entrie which is .efi file.
Take a look about this partition:
$ tree /boot/efi -d
/boot/efi
├── EFI
│ ├── Boot
│ ├── Microsoft
│ │ ├── Boot
│ │ │ ├── fr-FR
│ │ │ ├── ... others languages directories that I omitted ...
│ │ │ └── Resources
│ │ │ └── fr-FR
│ │ └── Recovery
│ └── systemd
└── loader
└── entries
Tips: I used the tree command to show you a tree of my file-system from /boot/efi with -d which mean only directories.
This is, what you got when you finished to install the bootloader, here we only saw directories.
As we can see, there is one pretty important folder which is EFI, on this folder there are all generated folders and files from Windows and our Linux. Furthermore, there is another folder which is loader that was generated when you install the systemd bootloader, we will see it later.
Requirements
Now, we are good to start, before install the systemd bootloader on Arch Linux, we have to check if the Linux has access to the efi variables and we gonna copy all required files to boot.
Check access to efi variables
So, we need to check if the folder /sys/firmware/efi exists, according to the Arch Wiki. Normaly, if you had boot on your live linux on uefi mode all are good.
You may have something like this:
$ ls -lisrt /sys/firmware/efi
total 0
12 0 drwxr-xr-x 2 root root 0 20 mai 15:33 efivars
6497 0 drwxr-xr-x 7 root root 0 20 mai 17:23 runtime-map
6494 0 -r--r--r-- 1 root root 4096 20 mai 17:23 runtime
6492 0 -r-------- 1 root root 4096 20 mai 17:23 systab
6495 0 -r--r--r-- 1 root root 4096 20 mai 17:23 config_table
6493 0 -r--r--r-- 1 root root 4096 20 mai 17:23 fw_vendor
6496 0 -r--r--r-- 1 root root 4096 20 mai 17:23 fw_platform_size
Tips: the ls command show you files on a directories
All are good? go to the next requirements.
Oh no! You cannot acces to this directory, you have to reboot in uefi mode.
Copy required files
We have to copy each initramfs and vmlinuz from each kernel in order to boot. I will only copy files for the linux kernel here.
Commands to do:
$ cp /boot/vmlinuz-linux /boot/efi/vmlinuz-linux
$ cp /boot/initramfs-linux.img /boot/efi/initramfs-linux.img
$ cp /boot/initramfs-linux-fallback.img /boot/efi/initramfs-linux-fallback.img
Installation
Finaly, we gotcha. Now, we had check that all requirements are satisfied, we can installed the bootloader.
$ bootctl --path=/boot/efi install
Copied "/usr/lib/systemd/boot/efi/systemd-bootx64.efi" to "/boot/efi/EFI/systemd/systemd-bootx64.efi".
Copied "/usr/lib/systemd/boot/efi/systemd-bootx64.efi" to "/boot/efi/EFI/BOOT/BOOTX64.EFI".
...
Tips: I used the --path=/boot/efi option because my ESP is located as /boot/efi, by default it wanna install on /boot.
We see output from the command that said to us which files were copied and a message to report to us that all are good. However, we see a message which mean that you were installed your bootloader on a no-EFI partition. You have to recheck on what partition we have to install the partiton, is it an ESP ? Recheck as well, all requirements.
Create Linux entries
Now, we have to create entries for our Linux to boot in. Do you remenber the previous schema about the ESP partition?
$ tree /boot/efi -d
/boot/efi
├── EFI
│ ├── Boot
│ ├── Microsoft
│ │ ├── Boot
│ │ │ ├── fr-FR
│ │ │ ├── ... others languages directories that I omitted ...
│ │ │ └── Resources
│ │ │ └── fr-FR
│ │ └── Recovery
│ └── systemd
└── loader
└── entries
Tips: I used the tree command to show you a tree of my file-system from /boot/efi with -d which mean only directories.
We need to create files with extension .conf, two per kernel. There are one for the casual use and the other one for the fallback use. We have to put them in the directory /boot/efi/loader/entries.
The casual use that I named arch-linux.conf:
title Arch Linux
linux /vmlinuz-linux
initrd /initramfs-linux.img
options root=UUID=<uuid> rw
Tips: To get the uuid of the root partition you can use the command lsblk -fs
The fallback use that I named arch-linux-fallback.conf:
title Arch Linux (fallback)
linux /vmlinuz-linux
initrd /initramfs-linux-fallback.img
options root=UUID=<uuid> rw
Tips: To get the uuid of the root partition you can use the command lsblk -fs
Files are pretty simple, we can take notice of the path of the vmlinuz and the initramfs are absolute and begin at the top of the ESP partition.
Update bootloader configuration
If you wanna update the timeout or change the default selected entrie that I did, you have to modify the file located at /boot/efi/loader/loader.conf, here there is an example:
default arch-linux
timeout 10
I set a timeout of 10 seconds and my default entrie is arch-linux.
Now, you can reboot without worried systemd-boot will automatically find Windows and Arch Linux.
If you wanna more information, refers you to the great Arch Wiki, it has so many secrets inside that they just ask to be discover.
Bonus: Update on Linux kernel or systemd update
On Arch Linux, the package manager knows as pacman may be hooked to do a command when a package is upgraded. To upgrade our vmlinuz, initiramfs files and systemd-boot configuration we need to create 4 files on the directory /etc/pacman.d/hooks (you may have to create it). Each file has the following structure :
[Trigger]
Type = Package
Operation = Upgrade
Target = <package>
[Action]
Description = <description>
When = PostTransaction
Exec = <command>
So, we have to write hooks when the package manager update the following packages which are linux and systemd. Followings there are hooks for the systemd upgrade:
Hook that I named systemd-boot.hook:
[Trigger]
Type = Package
Operation = Upgrade
Target = systemd
[Action]
Description = Updating systemd-boot ...
When = PostTransaction
Exec = /usr/bin/bootctl --path=/boot/efi update
Tips: Do you remember that I have to say where is my ESP partition with --path=/boot/efi option?
So, we can take notice from this hook that all binaries must have absolute path, it is needed. Furthermore, it looks like a systemd configuration file, isn’t it?
Now, hooks for the linux package upgrade, do not forget to do the same for each Linux kernel that you had installed.
Hook that I named vmlinuz-linux.hook:
[Trigger]
Type = Package
Operation = Upgrade
Target = linux
[Action]
Description = Updating vmlinuz-linux ...
When = PostTransaction
Exec = /usr/bin/cp -f /boot/vmlinuz-linux /boot/efi/vmlinuz-linux
Hook that I named initramfs-linux.hook:
[Trigger]
Type = Package
Operation = Upgrade
Target = linux
[Action]
Description = Updating initramfs-linux ...
When = PostTransaction
Exec = /usr/bin/cp -f /boot/initramfs-linux.img /boot/efi/initramfs-linux.img
Hook that I named initramfs-linux-fallback.hook:
[Trigger]
Type = Package
Operation = Upgrade
Target = linux
[Action]
Description = Updating initramfs-linux-fallback ...
When = PostTransaction
Exec = /usr/bin/cp -f /boot/initramfs-linux-fallback.img /boot/efi/initramfs-linux-fallback.img
Now, we can enjoy our beautiful systemd bootloader that update automaticaly.