The Linux boot-up sequence basically follows six steps to complete the boot-up sequence. Each step is responsible for (depends on) the next.
Basic Input Output System (BIOS)
- Searches and executes the boot loader program from the MBR.
- It is like an abstraction layer between the hardware and the software.
Master Boot Record (MBR)
- It is located in the first sector of the boot disk. It takes around.
- Some boot loaders are GRUB, LILO or Linux Loader.
KERNEL
- Located on a disk partition.
- It mounts the root file system.
- It contains drivers for hardware support.
- It executes the Init program.
INIT PROCESS
The INIT process is responsible for the run-levels:
- Halt
- Single user mode
- Multiuser mode without NFS
- Unused, For research purpose
- Full multiuser with Graphical mod
- Reboot
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