Appendix A. Cisco Configuration Basics

To configure a Cisco router, you must first be able to talk to it. Out of the box, the router doesn’t have any IP addresses yet, so the only way to access it is over the console port. On some models, the console port is an RJ-48 connector (identical to that of an UTP Ethernet port), on others, a 25-pin RS-232c connector. Use the supplied cable and connectors to connect the console port of the router to a terminal or a computer running a terminal emulation program. The terminal emulation program doesn’t have to be anything fancy; something like the Hyperterminal program that comes with many versions of Windows is good enough. The communication settings should be 9600 bps, 8 bits, no parity, no flow control, and full duplex/no local echo.

When you turn on the router, there should pretty much immediately be a message on the screen. If the message doesn’t appear, your cable probably needs to be “null-modemed,” or your communication settings are wrong. The router needs a minute or so to boot, and then it will ask you if you want to execute the initial setup dialog. Say “no.” Doing the initial configuration manually is easier and faster. The router should now display a prompt:


This is your cue to type “enable” to enable privileged mode, so you are allowed to perform configuration changes. This is something you’ll be doing a lot from now on.


Normally, the router will ask for the enable password, but since the configuration ...

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