Please describe the Linux boot-up sequence.

There are seven steps to the boot-up sequence.

1) BIOS (basic input/output system) – executes the MBR where Boot Loader sits,

2) MBR- Master boot reads Kernel into memory,

3) GRUB (Grand Unified Bootloader) Kernel starts Init process,

4) Kernel – Kernel executes the /sbin/init program.  Init reads inittab, executes rc.sysinit,

5) Init – the rc script than starts services to reach the default run level and

6) Run level programs – these programs are executed from /etc/rc.d/rc*.dl/