Chapter 13. The FreeBSD Booting Process

Table of Contents
13.1. Synopsis
13.2. The Booting Problem
13.3. The Boot Manager and Boot Stages
13.4. Kernel Interaction During Boot
13.5. Device Hints
13.6. Init: Process Control Initialization
13.7. Shutdown Sequence

13.1. 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 the system starts, including the ability to select from different operating systems installed on the same computer, different versions of the same operating system, or a different installed kernel.

This chapter details the configuration options that can be set. It demonstrates how to customize the FreeBSD boot process, including everything that happens until the FreeBSD kernel has started, probed for devices, and started init(8). This occurs when the text color of the boot messages changes from bright white to grey.

After reading this chapter, you will recognize:

  • The components of the FreeBSD bootstrap system and how they interact.

  • The options that can be passed to the components in the FreeBSD bootstrap in order to control the boot process.

  • The basics of device.hints(5).


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

All FreeBSD documents are available for download at

Questions that are not answered by the documentation may be sent to <>.

Send questions about this document to <>.