Configuring Native 802.1Q Vlans - Cisco AP775A - Nexus Converged Network Switch 5010 Configuration Manual

Configuring Native 802.1Q VLANs

This example shows how to add VLANs to the list of allowed VLANs on an Ethernet trunk port:
switch# configure terminal
switch(config)# interface ethernet 1/3
switch(config-if)# switchport trunk allow vlan 15-20
Configuring Native 802.1Q VLANs
Typically, you configure 802.1Q trunks with a native VLAN ID, which strips tagging from all packets on that
VLAN. This configuration allows all untagged traffic and control traffic to transit the Cisco Nexus 5000 Series
switch. Packets that enter the switch with 802.1Q tags that match the native VLAN ID value are similarly
stripped of tagging.
To maintain the tagging on the native VLAN and drop untagged traffic, enter the vlan dot1q tag native
command. The switch will tag the traffic received on the native VLAN and admit only 802.1Q-tagged frames,
dropping any untagged traffic, including untagged traffic in the native VLAN.
Control traffic continues to be accepted untagged on the native VLAN on a trunked port, even when the vlan
dot1q tag native command is enabled.
Note The vlan dot1q tag native command is enabled on global basis.
Procedure
Step 1
Step 2
Step 3
Step 4
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
108
Command or Action
Command or Action
switch# configure terminal
switch(config)# vlan dot1q tag
native
switch(config)# no vlan dot1q tag
native
switch# show vlan dot1q tag native
Configuring Access and Trunk Interfaces
Purpose
configurable. By default, all VLANs are allowed on all trunk
interfaces.
You cannot add internally allocated VLANs as
Note
allowed VLANs on trunk ports. The system returns
a message if you attempt to list an internally
allocated VLAN as an allowed VLAN.
Purpose
Enters configuration mode.
Enables dot1q (IEEE 802.1Q) tagging for all native
VLANs on all trunked ports on the Cisco Nexus 5000
Series switch. By default, this feature is disabled.
(Optional)
Disables dot1q (IEEE 802.1Q) tagging for all native
VLANs on all trunked ports on the switch.
(Optional)
Displays the status of tagging on the native VLANs.
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