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What Does Happen During Boot Process? - BIOS and MBR

 
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Old 12-11-2009
What Does Happen During Boot Process? - BIOS and MBR
I'm talking about boot process in multi-boot Linux perceptive.

Please tell me whether my explanation is right or wrong? If wrong, please explain.

"The BIOS checks the system and loads this initial bootstrapping code into
memory. This initial bootstrap code searches for an active partition and looks for a first sector of that active partition.

After that, bootstrap code gets whatever boot code (usually GRUB Stage 1) in the VBR and loads it in memory, so GRUB Stage 1 in this case overrides the MBR initial bootstrap that's in memory.

Once GRUB Stage 1 is in memory, it takes GRUB Stage 2 from /boot/ and loads it memory. Thus, GRUB Stage 2 overrides the GRUB Stage 1.

Now once GRUB Stage 2 is in memory, it presents an interface where the user
can select which OS to boot.

Once OS is selected, the GRUB stage 2 loads the selected Kernel into Memory, so the chosen OS Kernel overrides GRUB Stage 2.

Now this Kernel has the control and finishes the process. "

Thanks!
 
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LEARN ABOUT DEBIAN

cbios

C-BIOS(7)						 Miscellaneous Information Manual						 C-BIOS(7)

NAME

       C-BIOS - provides open source BIOS ROM files for MSX computers

DESCRIPTION

       This manual page documents briefly the C-BIOS rom files.

       This manual page was written for the Debian distribution because the original program does not have a manual page.

       C-BIOS is an open source BIOS for MSX computers. C-BIOS can be shipped with MSX emulators so they are usable out-of-the-box.

       Details	about the BIOS calls available in the ROM files can be found at http://map.tni.nl/ but keep in mind the C-BIOS is work in progress
       and does not support all BIOS calls yet.

       C-BIOS comes in three versions currently. C-BIOS_MSX1 is compatible with MSX1 machines, C-BIOS_MSX2 is compatible with MSX2 machines and C-
       BIOS_MSX2+ is compatible with MSX2+ machines.

       Each version comes in three localisation variants, an international, Japanse (JP) and Brazilian (BR) one.

SEE ALSO

       openmsx (1), openmsx-catapult (1), pasmo (1).

AUTHOR

       This  manual  page  was	written by Joost Yervante Damad for the Debian system (but may be used by others).  Permission is granted to copy,
       distribute and/or modify this document under the terms of the GNU General Public License, Version 2 or any later version published  by  the
       Free Software Foundation.

       On Debian systems, the complete text of the GNU General Public License can be found in /usr/share/common-licenses/GPL.

Joost Yervante Damad															 C-BIOS(7)