CLI Reference Guide-R04

Chapter 2 | Using the Command Line Interface
Entering Commands
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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?
sflow snmp snmp-server sntp spanning-tree
ssh startup-config subnet-vlan system
Console#show 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: