Linux · GRUB & Boot Process

You dual-boot Windows and Linux, but after a Linux update the GRUB menu no longer lists Windows. On Ubuntu 22.04+ / Debian 12+, why — and how do you get it back?

Answer locked. Get the free KnowCard app to reveal it — plus spaced-repetition review so it actually sticks.

This is one card from the KnowCard library — thousands more across SAP, Linux, Python and more. In the app you get the answer, AI explanations, and cards that come back right before you would forget them. Free to start on iOS, Android or the web.

More in GRUB & Boot Process

On a BIOS-based machine, you swap out a failed software-RAID disk, add its partitions back with mdadm, and the array resyncs cleanly. Why can that disk still fail to boot the machine?

You want to encrypt an entire Linux system including the root partition. Why can't you simply encrypt every partition and be done?

What role does GRUB play the instant a PC is switched on, and what three jobs does it handle?

On an EFI computer with three operating systems installed side by side, which component actually decides which OS boots — and where does that leave GRUB's menu?

On an EFI machine, where does GRUB's code physically live, and what must be true of that partition?

The kernel file is named /boot/vmlinuz. What does the trailing z signify, and what single parameter must the bootloader always pass to it?

Start learning today

Free to start — download the app or use it in your browser.