> For the complete documentation index, see [llms.txt](https://handbook.bsdcn.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://handbook.bsdcn.org/di-15-zhang-freebsd-de-yin-dao-guo-cheng/15.1.-gai-shu.md).

# 15.1.概述

引导计算机并加载操作系统的过程被称为“引导过程”（bootstrap process），或简称“引导”（booting）。FreeBSD 的引导过程在系统引导时提供了极大的灵活性，包括能够从同一计算机上安装的不同操作系统中进行选择，或从同一操作系统的不同版本、不同内核中进行选择。

本章将详细介绍可配置的选项，演示如何自定义 FreeBSD 的引导过程，包括从引导开始直到 FreeBSD 内核引导、探测设备并启动 [init(8)](https://man.freebsd.org/cgi/man.cgi?query=init\&sektion=8\&format=html) 之前发生的一切。当引导信息的文本颜色从亮白变为灰色时，表示此阶段已经完成。

阅读本章后，你将理解：

* FreeBSD 引导系统的各个组成部分及其如何相互作用；
* 可以传递给 FreeBSD 引导各组成部分的选项，以控制引导过程；
* 设置设备提示（device hints）的基本方法；
* 如何引导进入单用户或多用户模式，以及如何正确关闭 FreeBSD 系统。

> **注意**
>
> 本章仅介绍运行在 x86 和 amd64 系统上的 FreeBSD 引导过程。


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