Configuring and modifying the bootloader

- [Instructor] Booting the system, or starting it up…from a state where the operating system isn't running,…may seem like a trivial exercise.…You push the button, some stuff goes by on the screen…and then, after a while, you can actually use the computer;…but the process is a lot more complex than that.…When a Linux system starts up, there are a few layers…of activity that happen to get from a powered off state…to a condition where you can use the computer.…At the very beginning, the system starts up…and loads its firmware; and that software either knows…where to find, or goes and looks for,…a specially-designated area of storage…where the bootloader for the system is stored.…

Often, the software is GRUB,…or the grand unified bootloader;…though there are others, such as LILO.…The bootloader has information about where operating systems…on the disk are located and with what…settings they can be started up.…The bootloader starts up the kernel and initial file system,…which has the tools needed to mount the root file system;…