Using the Command-Line Interface

The Catalyst 3750 switch is supported by Cisco IOS software. This chapter describes how to use the switch command-line interface (CLI) to configure software features.

For a complete description of the commands that support these features, see "Cisco IOS Commands." For information on the boot loader commands, see "Boot Loader Commands." For information on the debug commands, see "Debug Commands." For information on the show platform commands, see "Show Platform Commands." For more information on Cisco IOS Release 12.1, refer to the Cisco IOS Release 12.1 Command Summary.

For task-oriented configuration steps, refer to the software configuration guide for this release.

Accessing the Switch

You manage the switch stack and the stack member interfaces through the stack master. You cannot manage stack members on an individual switch basis. You can connect to the stack master through the console port of one or more stack members. Be careful with using multiple CLI sessions to the stack master. Commands you enter in one session are not displayed in the other sessions. Therefore, it is possible to lose track of the session from which you entered commands.

Note We recommend using one CLI session when managing the switch stack.

If you want to configure a specific stack member port, you must include the stack member number in the CLI command interface notation. For more information about interface notations, refer to the "Configuring Interfaces" chapter in the software configuration guide for this release.

To debug a specific stack member, you can access it from the stack master by using the session stack-member-number privileged EXEC command. The stack member number is appended to the system prompt. For example, Switch-2# is the prompt in privileged EXEC mode for stack member 2, and the system prompt for the stack master is Switch. Only the show and debug commands are available in a CLI session to a specific stack member.

CLI Command Modes

This section describes the CLI command mode structure. Command modes support specific Cisco IOS commands. For example, the interface interface-id command only works when entered in global configuration mode.

These are the main command modes for the switch:

•User EXEC

•Privileged EXEC

•Global configuration

•Interface configuration

•Config-vlan

•VLAN configuration

•Line configuration

Table 1-1 lists the main command modes, how to access each mode, the prompt you see in that mode, and how to exit that mode. The prompts listed use the default name Switch.

Table 1-1 Command Modes Summary 

Command Mode
Access Method
Prompt
Exit or Access Next Mode

User EXEC

This is the first level of access.

(For the switch) Change terminal settings, perform basic tasks, and list system information. 

Switch>

Enter the logout command.

To enter privileged EXEC mode, enter the enable command.

Privileged EXEC

From user EXEC mode, enter the enable command. 

Switch#

To exit to user EXEC mode, enter the disable command.

To enter global configuration mode, enter the configure command.

Global configuration

From privileged EXEC mode, enter the configure command. 

Switch(config)#

To exit to privileged EXEC mode, enter the exit or end command, or press Ctrl-Z.

To enter interface configuration mode, enter the interface configuration command.

Interface configuration

From global configuration mode, specify an interface by entering the interface command followed by an interface identification. 

Switch(config-if)#

To exit to privileged EXEC mode, enter the end command, or press Ctrl-Z.

To exit to global configuration mode, enter the exit command.

Config-vlan

In global configuration mode, enter the vlan vlan-id command. 

Switch(config-vlan)#

To exit to global configuration mode, enter the exit command.

To return to privileged EXEC mode, enter the end command, or press Ctrl-Z.

VLAN configuration

From privileged EXEC mode, enter the vlan database command. 

Switch(vlan)#

To exit to privileged EXEC mode, enter the exit command.

Line configuration

From global configuration mode, specify a line by entering the line command. 

Switch(config-line)#

To exit to global configuration mode, enter the exit command.

To return to privileged EXEC mode, enter the end command, or press Ctrl-Z.


User EXEC Mode

After you access the device, you are automatically in user EXEC command mode. The EXEC commands available at the user level are a subset of those available at the privileged level. In general, use the user EXEC commands to temporarily change terminal settings, perform basic tests, and list system information.

The supported commands can vary depending on the version of software in use. To view a comprehensive list of commands, enter a question mark (?) at the prompt. 

Switch> ?

Privileged EXEC Mode

Because many of the privileged commands configure operating parameters, privileged access should be password-protected to prevent unauthorized use. The privileged command set includes those commands contained in user EXEC mode, as well as the configure privileged EXEC command through which you access the remaining command modes.

If your system administrator has set a password, you are prompted to enter it before being granted access to privileged EXEC mode. The password does not appear on the screen and is case sensitive.

The privileged EXEC mode prompt is the device name followed by the pound sign (#). 

Switch#

Enter the enable command to access privileged EXEC mode: 

Switch> enable 

Switch#

The supported commands can vary depending on the version of software in use. To view a comprehensive list of commands, enter a question mark (?) at the prompt. 

Switch# ?

To return to user EXEC mode, enter the disable privileged EXEC command.

Global Configuration Mode

Global configuration commands apply to features that affect the device as a whole. Use the configure privileged EXEC command to enter global configuration mode. The default is to enter commands from the management console.

When you enter the configure command, a message prompts you for the source of the configuration commands: 

Switch# configure 

Configuring from terminal, memory, or network [terminal]?

You can specify either the terminal or nonvolatile RAM (NVRAM) as the source of configuration commands.

This example shows you how to access global configuration mode: 

Switch# configure terminal 

Enter configuration commands, one per line.  End with CNTL/Z.

The supported commands can vary depending on the version of software in use. To view a comprehensive list of commands, enter a question mark (?) at the prompt. 

Switch(config)# ?

To exit global configuration command mode and to return to privileged EXEC mode, enter the end or exit command, or press Ctrl-Z.

Interface Configuration Mode

Interface configuration commands modify the operation of the interface. Interface configuration commands always follow a global configuration command, which defines the interface type.

Use the interface interface-id command to access interface configuration mode. The new prompt means interface configuration mode. 

Switch(config-if)#

The supported commands can vary depending on the version of software in use. To view a comprehensive list of commands, enter a question mark (?) at the prompt. 

Switch(config-if)# ?

To exit interface configuration mode and to return to global configuration mode, enter the exit command. To exit interface configuration mode and to return to privileged EXEC mode, enter the end command, or press Ctrl-Z.

config-vlan Mode

Use this mode to configure normal-range VLANs (VLAN IDs 1 to 1005) or, when VTP mode is transparent, to configure extended-range VLANs (VLAN IDs 1006 to 4094). When VTP mode is transparent, the VLAN and VTP configuration is saved in the running configuration file, and you can save it to the switch startup configuration file by using the copy running-config startup-config privileged EXEC command. The configurations of VLAN IDs 1 to 1005 are saved in the VLAN database if VTP is in transparent or server mode. The extended-range VLAN configurations are not saved in the VLAN database.

Enter the vlan vlan-id global configuration command to access config-vlan mode: 

Switch(config)# vlan 2000

Switch(config-vlan)#

The supported keywords can vary but are similar to the commands available in VLAN configuration mode. To view a comprehensive list of commands, enter a question mark (?) at the prompt. 

Switch(config-vlan)# ?

For extended-range VLANs, all characteristics except the MTU size must remain at the default setting.

To return to global configuration mode, enter exit; to return to privileged EXEC mode, enter end. All the commands except shutdown take effect when you exit config-vlan mode.

VLAN Configuration Mode

You can use the VLAN configuration commands to create or modify VLAN parameters for VLAN IDs 1 to 1005.

Enter the vlan database privileged EXEC command to access VLAN configuration mode: 

Switch# vlan database

Switch(vlan)#

The supported commands can vary depending on the version of software in use. To view a comprehensive list of commands, enter a question mark (?) at the prompt. 

Switch(vlan)# ?

To return to privileged EXEC mode, enter the abort VLAN configuration command to abandon the proposed database. Otherwise, enter exit to implement the proposed new VLAN database and to return to privileged EXEC mode. When you enter exit or apply, the configuration is saved in the VLAN database; configuration from VLAN configuration mode cannot be saved in the switch configuration file.

Line Configuration Mode

Line configuration commands modify the operation of a terminal line. Line configuration commands always follow a line command, which defines a line number. Use these commands to change terminal parameter settings line-by-line or for a range of lines.

Use the line vty line_number [ending_line_number] command to enter line configuration mode. The new prompt means line configuration mode. The following example shows how to enter line configuration mode for virtual terminal line 7: 

Switch(config)# line vty 0 7

The supported commands can vary depending on the version of software in use. To view a comprehensive list of commands, enter a question mark (?) at the prompt. 

Switch(config-line)# ?

To exit line configuration mode and to return to global configuration mode, use the exit command. To exit line configuration mode and to return to privileged EXEC mode, enter the end command, or press Ctrl-Z.