Cisco Systems 3560-X, 3750-X Configuring Layer 2 Tunneling for EtherChannels

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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 19 Configuring IEEE 802.1Q and Layer 2 Protocol Tunneling
Configuring Layer 2 Protocol Tunneling
Use the no l2protocol-tunnel [cdp | stp | vtp] interface configuration command to disable protocol
tunneling for one of the Layer 2 protocols or for all three. Use the no l2protocol-tunnel
shutdown-threshold [cdp | stp | vtp] and the no l2protocol-tunnel drop-threshold [cdp | stp | vtp]
commands to return the shutdown and drop thresholds to the default settings.
This example shows how to configure Layer 2 protocol tunneling for CDP, STP, and VTP and to verify
the configuration.
Switch(config)# interface gigabitethernet1/0/11
Switch(config-if)# l2protocol-tunnel cdp
Switch(config-if)# l2protocol-tunnel stp
Switch(config-if)# l2protocol-tunnel vtp
Switch(config-if)# l2protocol-tunnel shutdown-threshold 1500
Switch(config-if)# l2protocol-tunnel drop-threshold 1000
Switch(config-if)# exit
Switch(config)# l2protocol-tunnel cos 7
Switch(config)# end
Switch# show l2protocol
COS for Encapsulated Packets: 7
Port Protocol Shutdown Drop Encapsulation Decapsulation Drop
Threshold Threshold Counter Counter Counter
------- -------- --------- --------- ------------- ------------- -------------
Gi0/11 cdp 1500 1000 2288 2282 0
stp 1500 1000 116 13 0
vtp 1500 1000 3 67 0
pagp ---- ---- 0 0 0
lacp ---- ---- 0 0 0
udld ---- ---- 0 0 0
Configuring Layer 2 Tunneling for EtherChannels
To configure Layer 2 point-to-point tunneling to facilitate the automatic creation of EtherChannels, you
need to configure both the SP edge switch and the customer switch.
Configuring the SP Edge Switch
Beginning in privileged EXEC mode, follow these steps to configure a SP edge switch for Layer 2
protocol tunneling for EtherChannels:
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 interface interface-id Enter interface configuration mode, and enter the interface to be configured
as a tunnel port. This should be the edge port in the SP network that
connects to the customer switch. Valid interfaces are physical interfaces.
Step 3 switchport mode dot1q-tunnel Configure the interface as an IEEE 802.1Q tunnel port.
Step 4 l2protocol-tunnel point-to-point
[pagp | lacp | udld]
(Optional) Enable point-to-point protocol tunneling for the desired
protocol. If no keyword is entered, tunneling is enabled for all three
protocols.
Caution To avoid a network failure, make sure that the network is a
point-to-point topology before you enable tunneling for PAgP,
LACP, or UDLD packets.