17-13
Catalyst 3750 SwitchSoftware Configuration Guide
OL-8550-09
Chapter17 Configuring IEEE 802.1Q and Layer 2 Protocol Tunneling
Configuring Layer 2 Protocol Tunneling
Configuring Layer 2 Protocol Tunneling
Beginning in privileged EXEC mode, follow these steps to configure a port for Layer 2 protocol
tunneling:
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 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 service-provider
network that connects to the customer switch. Valid interfaces can be
physical interfaces and port-channel logical interfaces (port channels 1 to
48).
Step3 switchport mode access
or
switchport mode dot1q-tunnel
Configure the interface as an access port or an IEEE 802.1Q tunnel port.
Step4 l2protocol-tunnel [cdp | stp | vtp] Enable protocol tunneling for the desired protocol. If no keyword is entered,
tunneling is enabled for all three Layer 2 protocols.
Step5 l2protocol-tunnel
shutdown-threshold [cdp | stp | vtp]
value
(Optional) Configure the threshold for packets-per-second accepted for
encapsulation. The interface is disabled if the configured threshold is
exceeded. If no protocol option is specified, the threshold applies to each of
the tunneled Layer 2 protocol types. The range is 1 to 4096. The default is
to have no threshold configured.
Note If you also set a drop threshold on this interface, the
shutdown-threshold value must be greater than or equal to the
drop-threshold value.
Step6 l2protocol-tunnel drop-threshold
[cdp | stp | vtp] value
(Optional) Configure the threshold for packets-per-second accepted for
encapsulation. The interface drops packets if the configured threshold is
exceeded. If no protocol option is specified, the threshold applies to each of
the tunneled Layer 2 protocol types. The range is 1 to 4096. The default is
to have no threshold configured.
If you also set a shutdown threshold on this interface, the drop-threshold
value must be less than or equal to the shutdown-threshold value.
Step7 exit Return to global configuration mode.
Step8 errdisable recovery cause l2ptguard (Optional) Configure the recovery mechanism from a Layer 2
maximum-rate error so that the interface is re-enabled and can try again.
Errdisable recovery is disabled by default; when enabled, the default time
interval is 300 seconds.
Step9 l2protocol-tunnel cos value (Optional) Configure the CoS value for all tunneled Layer 2 PDUs. The
range is 0 to 7; the default is the default CoS value for the interface. If none
is configured, the default is 5.
Step10 end Return to privileged EXEC mode.
Step11 show l2protocol Display the Layer 2 tunnel ports on the switch, including the protocols
configured, the thresholds, and the counters.
Step12 copy running-config startup-config (Optional) Save your entries in the configuration file.