Chapter 1
Understanding Interface Numbering and Cisco IOS Software Basics
Command Modes
The Cisco IOS user interface involves different modes. Each command mode permits you to configure
different components on your router. The commands available at any given time depend on which mode
you are currently in. Entering a question mark (?) at the prompt displays a list of commands available
for each command mode.
Table 1-1
Command Mode
User EXEC
Privileged EXEC
Global configuration
Interface configuration
Each command mode restricts you to a subset of commands. If you are having trouble entering a
Timesaver
command, check the prompt, and enter the question mark (?) for a list of available commands. You might
be in the wrong command mode or using the wrong syntax.
In the following example, notice how the prompt changes after each command to indicate a new
command mode:
Router> enable
Password: <enable password>
Router# configure terminal
Router(config)# interface serial 0/0
Router(config-if)# line 0
Router(config-line)# controller T1/E1 slot/port <---See second Note below
Router(config-controller)# exit
Router(config)# exit
Router#
%SYS-5-CONFIG_I: Configured from console by console
The last message is normal and does not indicate an error. Press Enter to get the
OL-4306-03
Table 1-1
lists the most common command modes.
Common Command Modes
Access Method
Log in.
From user EXEC mode,
enter the enable
command.
From the privileged
EXEC mode, enter the
configure terminal
command.
From the global
configuration mode,
enter the interface type
number command, such
as interface serial 0/0.
Cisco IAD2430 Series Integrated Access Devices Software Configuration Guide
Understanding Cisco IOS Software Basics
Router Prompt
Displayed
Exit Method
Use the logout
Router>
command.
To exit to user EXEC
Router#
mode, use the disable,
exit, or logout
command.
To exit to privileged
Router (config)#
EXEC mode, use the
exit or end command,
or press Ctrl-Z.
To exit to global
Router (config-if)#
configuration mode, use
the exit command.
To exit directly to
privileged EXEC mode,
press Ctrl-Z.
prompt.
Router#
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