A serial line (null-modem cable) connects the machines through their serial ports.

一条串行线(空调制解调器电缆)将通过机器的串口连接它们。

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One common problem is that the null-modem cable could be connected to the wrong serial port.

一个常见的问题是，空调制解调器电缆可能会被连接到错误的串口。

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It is very important that you have the correct null modem cable with you to set up the debugging environment.

为了设置调试环境，拥有正确的零调制解调器电缆是非常重要的。

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Ideally, that machine would have no network connection (as it would be a prime break-in target), and be reported to via null-modem serial cable only.

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