Linux · GRUB & Boot Process

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?

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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 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?

The kernel needs modules to read the root file system, but those modules live on that same file system it can't yet read. How does the boot process escape this deadlock?

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