Boot Process in Debian / Ubuntu
From Free Knowledge Base- The DUCK Project: information for everyone
Boot up phases
There are 4 phases to starting up the system:
- BIOS
- Boot loader
- Kernel
- Upstart (which manages system tasks and services )
Kernel modules are loaded during the Kernel phase. The kernel uses a file system which is present in memory, called an 'initrd' for 'initial ram disk'. The kernel launches the init script inside the initrd file system, which loads hardware drivers and finds the root partition.
Upstart is the initialization scripts that run. These scripts involve different /etc/rc scripts and upstart events.