CLI Reference Guide-R07

Chapter 2 | Using the Command Line Interface
Entering Commands
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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:
Exec Commands When you open a new console session on the switch with the user name and
password “guest,” the system enters the Normal Exec command mode (or guest
mode), displaying the “Console>” command prompt. Only a limited number of the
commands are available in this mode. You can access all commands only from the
Privileged Exec command mode (or administrator mode). To access Privilege Exec
mode, open a new console session with the user name and password “admin.” The
Table 3: General Command Modes
Class Mode
Exec Normal
Privileged
Configuration
Global
*
* 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.
Access Control List
Class Map
DHCP
IGMP Profile
Interface
Line
Multiple Spanning Tree
Policy Map
Time Range
VLAN Database