Troubleshooting GRUB Bootloader: OS Detection Issues and Solutions

By pajus, 9 August, 2023

Introduction: The Challenge of Missing OS Detection in GRUB

If you're a Linux user who dual-boots multiple operating systems on your machine, you might have encountered a frustrating situation where the GRUB bootloader fails to detect other installed operating systems during boot. This issue can lead to a lack of options in the boot menu, leaving you unable to access your alternate OS installations. Fortunately, there's a simple solution that can help you regain control over your boot options.

Warning: The Issue at Hand

The primary reason behind missing OS detection in GRUB is often the non-execution of the os-prober tool. This tool is responsible for identifying other bootable partitions on your system, allowing GRUB to present them as options during boot. However, due to certain settings, os-prober might not be activated by default, leading to the problem of unrecognized operating systems in the boot menu.

Solution: Enabling os-prober for Accurate OS Detection

To address this issue and restore the missing OS entries in your GRUB boot menu, follow these steps:

  1. Open a terminal on your Linux system.
  2. Locate the /etc/default/grub configuration file and open it in a text editor (e.g., sudo nano /etc/default/grub).
  3. Look for the line that reads GRUB_DISABLE_OS_PROBER=true.
  4. Uncomment or add the line GRUB_DISABLE_OS_PROBER=false to enable the os-prober tool.
  5. Save and close the configuration file.
  6. Run the command sudo update-grub in the terminal to update your GRUB configuration.

After completing these steps, your GRUB bootloader should now be able to detect all installed operating systems on your machine.