What is Boot Process in Linux

Booting is the process or set of operation that loads and hence start the operating system, starting from the point when user switches on the power button. we can say that booting is the initialization of computerized system.  In this short article i am going to explain what is boot process in linux.
A boot loader is a computer program which load operating system and other software for computer after completion of power-on-self-test. A boot sequence is the set of operation that a computer performs when it is switched on.

Boot Devices :- 

The boot device is the device through which operating system is loaded . A modern computer BIOS support many devices for booting . These include floppy , hard disk , USB , network interface card and optical devices . The BIOS allows a user to configure boot order . A user can set boot order according to their preference . Suppose a user can set boot order as
                 1. USB
                 2. Hard drive
                 3. Network
In this condition first BIOS try to boot through USB , if it is not available then BIOS try to boot through Hard drive. If Hard drive is also not available then it try to boot through Network .If network is also not available, then the system will not boot.
Boot Sequence :-
There is a standard boot sequence that all computer runs. The general booting sequence are given below
1. Turn on the power button.
2. CPU pins are reset and registers are set to specific value
3. CPU jumps to address of BIOS (0xFFFF0)
4. BIOS runs POST (power-on-self-test)
5. Primary boot loader runs from MBR (Master Boot Record) and jump to secondary bootloader
6. Secondary bootloader load operating system.

In this short article , we have explained about boot process in linux .  Please subscribe to newsletter for updated articles. We will discuss about many other topics in next articles.