Category Archives: CISCO

Configuring the Native VLAN for 802.1Q Trunking Ports

If you do not configure this parameter, the trunk port uses the default VLAN as the native VLAN ID.

To configure native VLAN for a 802.1Q trunk port, perform this task:

Command
Purpose

Step 1

switch# configure terminal

Enters configuration mode.

Step 2

switch(config)# interface { type slot / port | port-channel number }

Specifies an interface to configure, and enters interface configuration mode.

Step 3

switch(config-if)# switchport trunk native vlan vlan-id

Sets the native VLAN for the 802.1Q trunk. Valid values are from 1 to 4094, except those VLANs reserved for internal use. The default value is VLAN1.

This example shows how to set the native VLAN for Ethernet 3/1 Ethernet trunk port to VLAN 5:

switch# configure terminal
switch(config)# interface ethernet 3/1
switch(config-if)# switchport trunk native vlan 5

Cisco Configuring Trunk Ports

onfigure a trunk port, perform this task:

Command
Purpose

Step 1

switch# configure terminal

Enters configuration mode.

Step 2

switch(config)# interface { type slot / port | port-channel number }

Specifies an interface to configure, and enters interface configuration mode.

Step 3

switch(config-if)# switchport mode { access | trunk }

Sets the interface as an Ethernet trunk port. A trunk port can carry traffic in one or more VLANs on the same physical link (VLANs are based on the trunk-allowed VLANs list). By default, a trunk interface can carry traffic for all VLANs. To specify that only certain VLANs are allowed on the specified trunk, use the switchport trunk allowed vlan command.

This example shows how to set Ethernet 3/1 as an Ethernet trunk port:

switch# configure terminal
switch(config)# interface ethernet 3/1
switch(config-if)# switchport mode trunk