Entering Commands 4

Partial Keyword Lookup

If you terminate a partial keyword with a question mark, alternatives that match the initial letters are provided. (Remember not to leave a space between the command and question mark.) For example “s?” shows all the keywords starting with “s.”

Console#show s?

snmp

sntp

spanning-tree ssh

startup-config

system

 

 

 

Console#sh s

 

 

 

Negating the Effect of Commands

For many configuration commands you can enter the prefix keyword “no” to cancel the effect of a command or reset the configuration to the default value. For example, the logging command will log system messages to a host server. To disable logging, specify the no logging command. This guide describes the negation effect for all applicable commands.

Using Command History

The CLI maintains a history of commands that have been entered. You can scroll back through the history of commands by pressing the up arrow key. Any command displayed in the history list can be executed again, or first modified and then executed.

Using the show history command displays a longer list of recently executed commands.

Understanding Command Modes

The command set is divided into Exec and Configuration classes. Exec commands generally display information on system status or clear statistical counters. Configuration commands, on the other hand, modify interface parameters or enable certain switching functions. These classes are further divided into different modes. Available commands depend on the selected mode. You can always enter a question mark “?” at the prompt to display a list of the commands available for the current mode. The command classes and associated modes are displayed in the following table:

Table 4-1 General Command Modes
Class

Mode

 

ExecNormal

 

 

Privileged

 

 

 

 

Configuration

Global*Access Control List

 

 

Interface

 

 

Line

 

 

Multiple Spanning Tree

 

 

VLAN Database

 

 

 

*You must be in Privileged Exec mode to access the Global configuration mode.

You must be in Global Configuration mode to access any of the other configuration modes.

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