4-11
Layer 3 Switching Software Feature and Configuration Guide
78-6235-04, Cisco IOS Release 12.0(10)W5(18)
Chapter4 Configuring Interfaces Configuring 802.1Q VLAN Encapsulation
Figure 4-3 Example of Bridging Between Native and Non-Native 802.1Q VLANs
To configure the bridging between native VLAN 1 and non-native VLAN 100 depicted in Figure 4-3,
perform the following steps:
encap dot1q 1 native
encap dot1q 100
Native VLAN 1
Non-native VLAN 100
1/0/0
1/0/1.2
1/0/1.1
3/0/1
Bridge-group 2
Bridge-group 1
Campus
switch
router
Campus
switch
router
28089
Command Purpose
Step1 Router(config)# interface fastethernet
slot/subslot/interface.subinterface Enters subinterface configuration mode.
Step2 Router(config-subif)# encap dot1q vlan-id native Specifies 802.1Q encapsulation for Ethernet
frames sent from the subinterface with a header
that maintains the specified native VLAN ID
between network nodes.
Step3 Router(config-subif)# bridge-group
bridge-group Assigns the subinterface a bridge group number.
Note When you are configuring VLAN
routing, skip this step.
Step4 Router(config-subif)# interface fastethernet
slot/subslot/interface Enters interface configurationmode to configure
the Fast Ethernet main interface.
Step5 Router(config-if)# bridge-group bridge-group Assigns the main interface to the bridge group.
Step6 Router(config-if)# exit Returns to global configuration mode.
Step7 Router(config)# bridge bridge-group protocol
ieee Specifiesthat the bridge group will use the IEEE
Ethernet Spanning Tree Protocol.