The Cisco IOS user interface is divided into many different modes. The commands available to you depend on which mode you are currently in. Enter a question mark (?) at the system prompt to obtain a list of commands available for each command mode.
You can start a CLI session through a console connection, through Telnet, a SSH, or by using the browser.
When you start a session, you begin in user mode, often called user EXEC
mode. Only a limited subset of the commands are available in user EXEC mode. For example,
most of the user EXEC commands are one-time commands, such as
show commands, which show the current configuration status,
and clear commands, which clear counters or interfaces. The user
EXEC commands are not saved when the switch reboots.
To have access to all commands, you must enter privileged EXEC mode. Normally, you must enter a password to enter privileged EXEC mode. From this mode, you can enter any privileged EXEC command or enter global configuration mode.
Using the configuration modes (global, interface, and line), you can make changes to the running configuration. If you save the configuration, these commands are stored and used when the switch reboots. To access the various configuration modes, you must start at global configuration mode. From global configuration mode, you can enter interface configuration mode and line configuration mode.
This table describes the main command modes, how
to access each one, the prompt you see in that mode, and how to exit the mode.
Table 1 Command Mode Summary
Mode
|
Access Method
|
Prompt
|
Exit Method
|
About This Mode
|
User EXEC
|
Begin a session using Telnet, SSH, or console.
|
SwitchControllerDevice>
|
Enter logout or
quit.
|
Use this mode to
|
Privileged EXEC
|
While in user EXEC mode, enter the enable
command.
|
SwitchControllerDevice#
|
Enter disable to exit.
|
Use this mode to verify commands that you have entered. Use a password to protect access to this mode.
|
Global configuration
|
While in privileged EXEC mode, enter the configure
command.
|
SwitchControllerDevice(config)#
|
To exit to privileged EXEC mode, enter exit or
end, or press Ctrl-Z.
|
Use this mode to configure parameters that apply to the entire switch.
|
VLAN configuration
|
While in global configuration mode, enter the vlan
vlan-id command.
|
SwitchControllerDevice(config-vlan)#
|
To exit to global configuration mode, enter the
exit command.
To return to privileged EXEC mode, press Ctrl-Z or enter
end.
|
Use this mode to configure VLAN parameters. When VTP mode is transparent, you can create extended-range VLANs (VLAN IDs greater than 1005) and save configurations in the switch startup configuration file.
|
Interface configuration
|
While in global configuration mode, enter the
interface command (with a specific
interface).
|
SwitchControllerDevice(config-if)#
|
To exit to global configuration mode, enter
exit.
To return to privileged EXEC mode, press Ctrl-Z or enter
end.
|
Use this mode to configure parameters for the Ethernet ports.
|
Line configuration
|
While in global configuration mode, specify a line with the
line vty or line
console command.
|
SwitchControllerDevice(config-line)#
|
To exit to global configuration mode, enter
exit.
To return to privileged EXEC mode, press Ctrl-Z or enter
end.
|
Use this mode to configure parameters for the terminal line.
|