Configuring The Customer Switch - Cisco Catalyst 3750-X Software Configuration Manual

Configuring Layer 2 Protocol Tunneling

Configuring the Customer Switch

After configuring the SP edge switch, begin in privileged EXEC mode and follow these steps to
configure a customer switch for Layer 2 protocol tunneling for EtherChannels:
Command
Step 1
configure terminal
Step 2 interface interface-id
Step 3 switchport trunk encapsulation
dot1q
Step 4 switchport mode trunk
Step 5
udld enable
Step 6
channel-group channel-group-number
mode desirable
Step 7
exit
Step 8
interface port-channel port-channel
number
Step 9
shutdown
Step 10 no shutdown
Step 11
end
Step 12
show l2protocol
Step 13
copy running-config startup-config
Use the no switchport mode trunk, the no udld enable, and the no channel group
channel-group-number mode desirable interface configuration commands to return the interface to the
default settings.
For EtherChannels, you need to configure both the SP edge switches and the customer switches for
Layer 2 protocol tunneling. (See
This example shows how to configure the SP edge switch 1 and edge switch 2. VLANs 17, 18, 19, and 20
are the access VLANs, Fast Ethernet interfaces 1 and 2 are point-to-point tunnel ports with PAgP and
UDLD enabled, the drop threshold is 1000, and Fast Ethernet interface 3 is a trunk port.
SP edge switch 1 configuration:
Switch(config)# interface gigabitethernet1/0/1
Switch(config-if)# switchport access vlan 17
Switch(config-if)# switchport mode dot1q-tunnel
Switch(config-if)# l2protocol-tunnel point-to-point pagp
Switch(config-if)# l2protocol-tunnel point-to-point udld
Switch(config-if)# l2protocol-tunnel drop-threshold point-to-point pagp 1000
Switch(config-if)# exit
Switch(config)# interface gigabitethernet1/0/2
Switch(config-if)# switchport access vlan 18
Switch(config-if)# switchport mode dot1q-tunnel
Switch(config-if)# l2protocol-tunnel point-to-point pagp
Switch(config-if)# l2protocol-tunnel point-to-point udld
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
19-16
Chapter 19
Purpose
Enter global configuration mode.
Enter the interface configuration mode. This should be the customer switch
port.
Set the trunking encapsulation format to IEEE 802.1Q.
Enable trunking on the interface.
Enable UDLD in normal mode on the interface.
Assign the interface to a channel group, and specify desirable for the PAgP
mode. For more information about configuring EtherChannels, see
Chapter 40, "Configuring EtherChannels and Link-State Tracking."
Return to global configuration mode.
Enter port-channel interface mode.
Shut down the interface.
Enable the interface.
Return to privileged EXEC mode.
Display the Layer 2 tunnel ports on the switch, including the protocols
configured, the thresholds, and the counters.
(Optional) Save your entries in the configuration file.
Figure 19-6 on page
Configuring IEEE 802.1Q and Layer 2 Protocol Tunneling
19-10.)
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