This low-level area of the hardware allows you to reset a hung system, boot from a specific device (like a CD or a network boot), or get into single-user mode.

硬件的这个低级区域允许您从特定的设备（如CD或网络）启动重新设置挂起的系统，或允许您进入单用户模式。

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With GRUB in particular, being able to boot into single-user mode could pose a serious security hole.

特别是使用GRUB 时，因为能够引导到单用户模式，所以是一个严重的安全漏洞。

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In Figure 4, our message file contains the text "Booting pinguino >>>", and we again boot into single-user mode using the S parameter.

在图4 中，我们的消息文件包含文本 "Booting pinguino >>>"，我们再次使用S 参数引导到单用户模式。

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Then press Enter, B, and the kernel will boot up to single-user mode. Once here you can run the passwd command, changing password for user root

然后按Enter 和B，内核会启动到单用户模式。

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Then press Enter, B, and the kernel will boot up to single-user mode. Once here you can run the passwd command, changing password for user root

然后按Enter 和B，内核会启动到单用户模式。

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