
15-12
Catalyst 3550 Multilayer Switch Software Configuration Guide
78-11194-09
Chapter 15 Configuring 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 how to
verify the configuration.
Switch(config)# interface FastEthernet0/11
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
Step 5
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.
Step 6
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.
Note
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.
Step 7
exit
Return to global configuration mode.
Step 8
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.
Step 9
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.
Step 10
end
Return to privileged EXEC mode.
Step 11
show l2protocol
Display the Layer 2 tunnel ports on the switch, including the protocols
configured, the thresholds, and the counters.
Step 12
copy running-config startup-config
(Optional) Save your entries in the configuration file.
Command
Purpose