Configuring Lan Interfaces For Layer 2 Switching; Configuring A Lan Port For Layer 2 Switching - Cisco 7609 Configuration Manual

Chapter 7 Configuring LAN Ports for Layer 2 Switching

Configuring LAN Interfaces for Layer 2 Switching

These sections describe how to configure Layer 2 switching on the Cisco 7600 series routers:
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Configuring a LAN Port for Layer 2 Switching

To configure a LAN port for Layer 2 switching, perform this task:
Command
Step 1
Router(config)# interface type
Step 2
Router(config-if)# shutdown
Step 3
Router(config-if)# switchport
Router(config-if)# no switchport
Step 4
Router(config-if)# no shutdown
Step 5
Router(config-if)# end
Step 6
Router# show running-config interface
1
[type slot/port]
Step 7
Router# show interfaces [type
switchport
Step 8
Router# show interfaces [type
1. type = ethernet, fastethernet, gigabitethernet, or tengigabitethernet
After you enter the switchport command, the default mode is switchport mode dynamic desirable. If
the neighboring port supports trunking and is configured to allow trunking, the link becomes a Layer 2
trunk when you enter the switchport command. By default, LAN trunk ports negotiate encapsulation. If
the neighboring port supports ISL and 802.1Q encapsulation and both ports are set to negotiate the
encapsulation type, the trunk uses ISL encapsulation (10-Gigabit Ethernet ports do not support ISL
encapsulation).
78-14064-04
Configuring a LAN Port for Layer 2 Switching, page 7-7
Configuring a Layer 2 Switching Port as a Trunk, page 7-8
Configuring a LAN Interface as a Layer 2 Access Port, page 7-14
Use the default interface {ethernet | fastethernet | gigabitethernet | tengigabitethernet}
slot/port command to revert an interface to its default configuration.
With Release 12.1(11b)E and later, when you are in configuration mode you can enter EXEC
mode-level commands by entering the do keyword before the EXEC mode-level command.
1
slot/port
1
slot/port]
1
slot/port] trunk
Purpose
Selects the LAN port to configure.
(Optional) Shuts down the interface to prevent traffic flow
until configuration is complete.
Configures the LAN port for Layer 2 switching.
Note You must enter the switchport command once
without any keywords to configure the LAN port
as a Layer 2 port before you can enter additional
switchport commands with keywords.
Clears Layer 2 LAN port configuration.
Activates the interface. (Required only if you shut down
the interface.)
Exits configuration mode.
Displays the running configuration of the interface.
Displays the switch port configuration of the interface.
Displays the trunk configuration of the interface.
Cisco 7600 Series Router Cisco IOS Software Configuration Guide—12.1E
Configuring LAN Interfaces for Layer 2 Switching
7-7