Linux

Better Windows dual-boot with systemd-boot

25 May 2023 • 1 min read

If you are dual-booting Linux and Windows, but rebooting into Grub and selecting Windows manually is too much effort, then this article is for you.

Setting up quick dual-boot

Let’s check if you are using systemd-boot. If you see “Yay” you can proceed, otherwise you need to install systemd-boot.
```
ls /boot/efi/loader/ | grep -q loader.conf && echo "Yay" || echo "Nay"
```

Check if the OS you want to boot already has a loader configuration. If so, you can proceed to 3.

ls /boot/efi/loader/entries

If you don’t have a loader configuration for Windows yet, try
```
 ls /boot/efi/EFI/
```
check if there is a folder called “Windows” or similar and write down the *.efi file

If there is no entry, you need to copy it over from the Windows drive or partition

 lsblk -o NAME,FSTYPE,SIZE,MOUNTPOINT

 NAME            FSTYPE        SIZE MOUNTPOINT
 nvme0n1                     476,9G 
 ├─nvme0n1p1     ntfs          450M 
 ├─nvme0n1p2     vfat          100M 
 ├─nvme0n1p3                    16M 
 ├─nvme0n1p4     ntfs        475,6G 
 └─nvme0n1p5     ntfs          850M 

In the output above, the partition nvme0n1p2 is the Windows MBR. Usually, the partition is 100 MB. Let’s mount the partition and copy over the EFI file.

 sudo mount /dev/nvme0n1p2 /mnt/win-efi
 sudo cp -r /mnt/win-efi/EFI/Microsoft /boot/efi/EFI
 umount /mnt/win-efi/

Now that you have the correct efi file, create the correct loader configuration. You need to adjust the path to the efi file path from step 2.
```
echo "title Windows
efi /EFI/Microsoft/Boot/bootmgfw.efi" > /boot/efi/loader/entries/windows-boot.conf
```

At this point you are already done and you can use systemctl to reboot into Windows.

systemctl reboot --boot-loader-entry=windows-boot

Bonus

Create a desktop entry so you can reboot via your launcher

sudo echo "#!/bin/sh
systemctl reboot --boot-loader-entry=windows-boot" > /opt/boot-into-windows

sudo chmod  +x /opt/reboot-into-windows

echo "[Desktop Entry]
Version=1.0
Type=Application
Terminal=false
# Add your own icon
Icon=~/.local/share/applications/windows.png
Name=Boot Windows
Comment=Reboot into Windows
Exec=/opt/boot-into-windows
Categories=Utility;
" > ~/.local/share/applications/windows.desktop

chmod +x ~/.local/share/applications/windows.desktop

Now you can type Windows in your launcher, press enter and directly boot into Windows.