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The FreeBSD Booting Process

Chapter 12 The FreeBSD Booting Process

Table of Contents
12.1 Synopsis
12.2 The Booting Problem
12.3 The Boot Manager and Boot Stages
12.4 Kernel Interaction During Boot
12.5 Device Hints
12.6 Init: Process Control Initialization
12.7 Shutdown Sequence

12.1 Synopsis

The process of starting a computer and loading the operating system is referred to as “the bootstrap process”, or simply “booting”. FreeBSD's boot process provides a great deal of flexibility in customizing what happens when you start the system, allowing you to select from different operating systems installed on the same computer, or even different versions of the same operating system or installed kernel.

This chapter details the configuration options you can set and how to customize the FreeBSD boot process. This includes everything that happens until the FreeBSD kernel has started, probed for devices, and started init(8). If you are not quite sure when this happens, it occurs when the text color changes from bright white to grey.

After reading this chapter, you will know:

x86 Only: This chapter only describes the boot process for FreeBSD running on Intel x86 systems.

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