Specifications

Using the Command-Line Interface in Cisco IOS Software
Using the CLI
xxxii
Changing the Default Settings for a Console or AUX Port
There are only two changes that you can make to a console port and an AUX port:
• Change the port speed with the config-register 0x command. Changing the port speed is not
recommended. The well-known default speed is 9600.
• Change the behavior of the port; for example, by adding a password or changing the timeout value.
Note The AUX port on the Route Processor (RP) installed in a Cisco ASR 1000 series router does not serve
any useful customer purpose and should be accessed only under the advisement of a customer support
representative.
Using the CLI
This section describes the following topics:
• Understanding Command Modes, page xxxii
• Using the Interactive Help Feature, page xxxv
• Understanding Command Syntax, page xxxvi
• Understanding Enable and Enable Secret Passwords, page xxxvii
• Using the Command History Feature, page xxxviii
• Abbreviating Commands, page xxxix
• Using Aliases for CLI Commands, page xxxix
• Using the no and default Forms of Commands, page xl
• Using the debug Command, page xl
• Filtering Output Using Output Modifiers, page xl
• Understanding CLI Error Messages, page xli
Understanding Command Modes
The CLI command mode structure is hierarchical, and each mode supports a set of specific commands.
This section describes the most common of the many modes that exist.
Table 3 lists common command modes with associated CLI prompts, access and exit methods, and a
brief description of how each mode is used.