Which file contains the default settings for the bootloader?

The file containing the default settings for the bootloader is located at /etc/default/grub. This file is specifically used by the GRUB (GRand Unified Bootloader) system, which is the most common bootloader used in Linux distributions. Within this file, you will find various configuration options that control how GRUB behaves during the boot process, including the default kernel to boot, the timeout duration, and additional parameters that can be passed to the kernel.

The other options represent different files related to GRUB, but they do not serve the same purpose as /etc/default/grub. The /boot/grub.cfg file is generated automatically by running the grub-mkconfig command and contains all the configurations and entries that GRUB uses at boot time, making it not directly editable for configuration purposes. The /usr/local/grub/config path is not a standard directory for GRUB configurations in most Linux systems; therefore, it is not relevant in this context. Similarly, /boot/grub/grub.default is typically a file that may relate to default selections but does not hold the comprehensive default settings as /etc/default/grub does.

Thus, understanding the purpose of /etc/default/grub helps establish its importance and relevance in configuring bootloader settings