Chapter 30. Boot Process, Init, and Shutdown

Chapter 30. Boot Process, Init, and Shutdown

30.1. The Boot Process
30.2. A Detailed Look at the Boot Process
30.2.1. The BIOS
30.2.2. The Boot Loader
30.2.3. The Kernel
30.2.4. The /sbin/init Program
30.3. Running Additional Programs at Boot Time
30.4. SysV Init Runlevels
30.4.1. Runlevels
30.4.2. Runlevel Utilities
30.5. Shutting Down

An important and powerful aspect of Red Hat Enterprise Linux is the open, user-configurable method it uses for starting the operating system. Users are free to configure many aspects of the boot process, including specifying the programs launched at boot-time. Similarly, system shutdown gracefully terminates processes in an organized and configurable way, although customization of this process is rarely required.

Understanding how the boot and shutdown processes work not only allows customization, but also makes it easier to troubleshoot problems related to starting or shutting down the system.


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