heise+ | Desinfec't: Repairing a Broken Grub Bootloader on Linux

What the article covers

A computer may refuse to start Linux because its bootloader is damaged. The bootloader is the small program that starts the operating system. The article shows how to use the boot menu of the Desinfec't USB stick to start the installed Linux. If that fails, you can mount the file system and fix or reinstall the bootloader from there.

First things to try

Sometimes the problem is easy to solve. In the BIOS boot menu, you can pick Linux by hand. If that does not work, GRUB in Desinfec't can help. To reach the GRUB command line, press the key C in the boot menu. The GRUB console uses a US keyboard layout, so the German layout is not available.

Key facts

• Press C in the boot menu to open the GRUB console.
• GRUB uses a US keyboard layout, not a German one.
• A USB stick is usually seen first and named (hd0) in GRUB.
• The first hard drive or SSD is then usually named (hd1), but this is not guaranteed.
• Other USB drives can change the drive order.

Why it matters

If a Linux computer will not start, the user may lose access to their files and programs. This guide shows a way to get the system running again without a full reinstall. Because drive names can change, users must check carefully which drive they are working on.

What to check next

• Read the full heise+ article for the exact GRUB commands.
• Check which drive is the installed Linux system before making changes.
• Use the US keyboard layout when typing commands in GRUB.