whatis bootloader
Bootloader (GRUB)
Also known as: GRUB, GRUB2, systemd-boot
The program firmware runs to load the Linux kernel and initramfs. GRUB is the most common; systemd-boot is a simpler UEFI-only option.
What Is a Bootloader (GRUB) in Linux?
GRUB shows the boot menu, lets you choose kernels or other operating systems, and passes kernel command-line parameters. Its config is generated from /etc/default/grub and /etc/grub.d/, not edited directly.
systemd-boot is minimal: it reads simple entry files from the ESP and has no scripting. Both let you press e at the menu to edit parameters for one boot, which is invaluable for recovery.
Example
sudo grub-mkconfig -o /boot/grub/grub.cfgLearn more about Bootloader (GRUB)
- GRUB Explained: Configuration, Kernel Parameters, and Repair GRUB is the last thing that runs before the kernel and the first thing to blame when a machine will not boot. Here is how its configuration actually works and why editing the generated file is the wrong move.
- systemd-boot vs GRUB: Choosing a Bootloader and Switching GRUB does everything and is complicated. systemd-boot does UEFI only, in about twenty lines of config, and cannot read your Btrfs root. Which trade-offs matter, and how to switch without losing the ability to boot.
- How to Dual Boot Linux and Windows Dual booting lets you run Linux and Windows on the same machine, choosing which to start at boot. This guide covers the right order to install them, how to resize Windows partitions, how GRUB handles the boot menu, and common problems to avoid.