Linux operating system boot process Detailed
Ten Steps need to boot
The first step: POST ( the BIOS) is to start work before their own tools to check whether it is normal, if normal then the next step may be normal if the step you have to detect where the problem is handled. BIOS is actually a self-test procedure to boot first on the motherboard comes with the necessary equipment and some of the external power-detect on the motherboard, such as CPU, video card, memory, hard drives and other devices that process of self-self-test
Step two: the MBR boot, is equipped with an on guides on the master boot record of the hard disk linux system, in the master boot record on the hard disk to the first physical partition, the hard disk is capable of reading the data by this main MBR master boot record, if this gives a 512-byte hard drive is lost then this will not work. It contains a hard disk master boot program and the hard disk partition table, partition table records four partitions each partition representing 16 bytes Total 64 bytes, and 446 bytes discharge master boot program, 2 bytes with for verification.
The third step: GRUB menu, which is the operating system boot menu
Step four: load the kernel ( Kernel) , which is the core of the operating system to start
Step Five: Run the INIT process, the init process is the main, its PID number is 1 which is the first one executed process
Step Six: read / etc / inittab configuration file, which is the default when linux boot mode. In the / etc / inittab This file can modify the configuration to the next power-on default boot option
Step Seven: Execute /etc/rc.d/rc.sysinit initialization script, which is initialized init process to perform kernel tasks
Step eight: Perform /etc/rc.d/rc script, find the default startup mode by executing the script option to start the process
Step 9: execution /etc/rc.d.rc.local individual configuration script, which is the user wants to boot from the start of the process are placed in command or script file, so set the boot from Kai way safer. This boot all the commands in the script file to execute all again
Step 10: Start mingetty process
Then the user can see the login screen, you can log in the system