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Note: Native VLAN is the VLAN that you configure on the Catalyst interface before you configure the trunking on that interface. By default, all interfaces are in VLAN 1. Therefore, VLAN 1 is the native VLAN that you can change. On an 802.1Q trunk, all VLAN packets except the native VLAN are tagged. You must configure the native VLAN in the same way on each side of the trunk. Then, the router or switch can recognize to which VLAN a frame belongs when the router or switch receives a frame with no tag. In the diagram in this section, VLAN 10 has been configured as the native VLAN. For interVLAN routing, be sure to configure the default gateway on all workstations that connect to the switches. This default gateway is the IP address that you configure on the subinterface. You create a subinterface on the router for each VLAN. In this example, workstation1 has been configured with default gateway 10.10.10.1. This gateway is the IP address of subinterface port channel 1.10. Workstation2 has been configured with default gateway 10.10.11.1. This gateway is the IP address of subinterface port channel 1.20.
Configuring EtherChannel and 802.1Q Trunking Between Catalyst L2 Fixed Configuration Switches and a Router (InterVLAN Ro…