> 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-3-zhang-freebsd-ji-chu/3.11.-she-bei-he-she-bei-jie-dian.md).

# 3.11.设备和设备节点

设备是主要用于说明系统中硬件相关活动的术语，包括磁盘、打印机、显卡和键盘。当 FreeBSD 引导时，大多数引导消息都与设备检测有关。这些引导消息的副本会保存到 `/var/run/dmesg.boot` 文件中。

每个设备都有一个设备名称和编号。例如，`ada0` 是第一个 SATA 硬盘，而 `kbd0` 表示键盘。

FreeBSD 中大多数设备都需要通过位于 `/dev` 目录下的特殊文件（称为设备节点）来访问。


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