Clear Linux* OS uses the Systemd-Boot boot loader, which does not support multi- booting without manual manipulation. This tutorial shows how to configure the Clear Linux OS boot loader to work with other OSes.

Process overview

The process to install other operating systems for a multi-booting computer is described below. Install Clear Linux OS first, then install other operating systems in any order.

  1. Install Clear Linux OS first with a EFI partition large enough to store the kernels of other operating systems and their initrds, in the case of Linux distributions.
  2. Install the next operating system without creating its own EFI partition.
  3. Boot into the newly installed operating system.
  4. For Linux distributions, copy its kernel and initrd to the Clear Linux OS EFI partition. This step is not needed for Windows*.
  5. Add an entry for the newly installed operating system in the Systemd-Boot menu.
  6. Make Systemd-Boot the default boot loader.
  7. Repeat the previous steps to install each additional operating system.

If you update any installed operating systems, be aware that:

  • The default boot loader may change from Clear Linux OS Systemd-Boot. Perform the steps in Restore the Clear Linux* OS boot loader.
  • Linux kernels or initrd images may change. Keep their corresponding Systemd-Boot /boot/efi/loader/entries/*.conf files up-to-date.

This process is not guaranteed to work with all Linux distributions and all their versions. The next section lists the OSes that we tested.

Tested operating systems

The following operating systems were tested on an Intel® NUC6i7KYK with 32GB RAM and a 360GB SSD. Table 1 lists the information specific to the installation of the tested operating systems.

Table 1: OS specific installation information
# OS Version Partition Size [1] Swap Size [2] EFI Partition Size [3] Download Link
1 Clear Linux 16140 50 GB 8 GB 1 GB
2 Windows Server 2016 50 GB N/A Shared with #1
3 Red Hat* Server 7.4 Beta 45 GB Shared with #1 Shared with #1
4 SUSE* Server 12 SP2 45 GB Shared with #1 Shared with #1
5 Ubuntu* 16.04.02 LTS Desktop 40 GB Shared with #1 Shared with #1
6 Linux Mint* 18.1 Serena MATE 40 GB Shared with #1 Shared with #1

Table notes:

[1] Configure the partition size as desired.
[2] To save disk space, share a single swap partition between multiple Linux installations. Swap size was determined using these recommended swap partition sizes.
[3] The EFI partition holds the kernel and boot information for Clear Linux OS and other operating systems. The partition size is dependent on the number of operating systems to be installed. In general, allocate about 100 MB per operating system. For this tutorial, we used 1 GB.

Install Clear Linux OS

Navigation tips for text-based installation interfaces:

  • Use the Up Arrow and Down Arrow keys to move between the options on the screen.
  • Use the Space to select or highlight an option.
  • Press Enter to activate the selected option and to move ahead.

Installation details

  1. Create a bootable USB drive of the Clear Linux OS installer using one of the methods below.

  2. Start the Clear Linux OS installer and follow the prompts.

  3. On the Choose Installation Type screen, choose Manual (Advanced), as shown in Figure 1.


    Figure 1: Clear Linux OS installer: Choose installation type screen.

  4. On the Choose partitioning method screen, choose Manually configure mounts and partitions, as shown in Figure 2.


    Figure 2: Clear Linux OS: Choose partitioning method.

  5. Select the drive, in this case /dev/sda, and press Enter to go into the cgdisk partitioning tool. See Figure 3.


    Figure 3: Clear Linux OS: Choose drive to partition.

  6. Create a new root partition.

    1. Select New, as shown in Figure 4.


      Figure 4: Clear Linux OS: Create new partition.

    2. Accept the default first sector.

    3. Specify the desired size of the partition. For this example, we specified 50 GB. See Figure 5.


      Figure 5: Clear Linux OS: New partition size.

    4. Set the partition type to 8300 (Linux filesystem), as shown in Figure 6.


      Figure 6: Clear Linux OS: Set partition type.

    5. Name the partition CL-root. This name makes it easier to identify later. See Figure 7.


      Figure 7: Clear Linux OS: Name partition.

  7. Create a new swap partition as shown in Figure 8.


    Figure 8: Clear Linux OS: Create swap partition.

    1. Select the free space partition located at the bottom of the column.
    2. Select New. See Figure 4.
    3. Accept the default first sector.
    4. Specify the desired size of the swap partition. For this example, we used 8 GB. See the recommended swap partition sizes for guidance.
    5. Set the partition type to 8200 (Linux swap).
    6. Name the partition CL-swap.
  8. Create a new EFI partition as shown in Figure 9.


    Figure 9: Clear Linux OS: Create EFI partition.

    1. In the Partition Type column, select free space located at the bottom of the column.
    2. Select New. See Figure 4.
    3. Accept the default first sector.
    4. Specify the desired size of the partition. For this example, we used 1024 MB. This partition will hold Clear Linux OS, the kernels of the other operating systems, and their boot information. Its size depends on the number of installed operating systems. In general, allocate about 100 MB per operating system. For this example, we used 1024 MB.
    5. Set the partition type to ef00 (EFI partition).
    6. Name the partition CL-EFI.
  9. Select Write to apply the new partition table.

  10. Select Quit to exit the cgdisk tool.

  11. On the Set mount points screen, specify the mount points and format settings as shown in Figure 10.


    Figure 10: Clear Linux OS: Set mount points.

  12. On the User configuration screen, select Create an administrative user, as shown in Figure 11.


    Figure 11: Clear Linux OS: User configuration.

  13. Select Add user to sudoers?, as shown in Figure 12.


    Figure 12: Clear Linux OS: Add user as sudoer.

  14. Follow the remaining prompts to complete the installation and finish the out-of-box-experience for Clear Linux OS.

  15. Log in.

  16. Add a Systemd-Boot timeout period or Systemd-Boot will not present the boot menu of available OSes to choose from and will always boot Clear Linux OS.

    sudo clr-boot-manager set-timeout 20
    sudo clr-boot-manager update
  17. Reboot.

If you want to install other OSes, refer to Detailed procedures.