This guide is part of the Multi-boot Clear Linux* OS with other operating systems tutorial. If you install a new OS or upgrade an existing OS, the default boot loader may change from Clear Linux OS Systemd-Boot. This guide describes how to restore Systemd-Boot.
Boot the Clear Linux OS installer from a USB thumb drive. See Create a bootable Clear Linux* OS USB drive.
At the introduction screen, press Control+Alt+F2 to bring up the Clear Linux OS console. See Figure 1.
Log in as root.
When you log in for the first time as root through the console, you must set a new password.
Find the location of the Clear Linux OS EFI partition. In this example, it is /dev/sda3. See Figure 2.
Mount the EFI partition.
mount /dev/sda3 /mnt
Re-install Systemd-Boot to make it the default boot loader.
bootctl install --path /mnt
Unmount the EFI partition.
If you want to install other OSes, refer to Multi-boot Clear Linux* OS with other operating systems for details.