Virtual LANs (VLAN) | 1061
Native VLANs
Traditionally, ports can be either untagged for membership to one VLAN or tagged for membership to
multiple VLANs. An untagged port must be connected to a VLAN-unaware station (one that does not
understand VLAN tags), and a tagged port must be connected to a VLAN-aware station (one that generates
and understands VLAN tags).
Native VLAN support breaks this barrier so that a port can be connected to both VLAN-aware and
VLAN-unaware stations. Such ports are referred to as hybrid ports. Physical and port-channel interfaces
may be hybrid ports.
Native VLAN is useful in deployments where a Layer 2 port can receive both tagged and untagged traffic
on the same physical port. The classic example is connecting a VOIP phone and a PC to the same port of
the switch. The VOIP phone is configured to generate tagged packets (with VLAN = VOICE VLAN), and
the attached PC generates untagged packets.
To configure a port so that it can be a member of an untagged and tagged VLANs:
Step Task Command Command Mode
1 Remove any Layer 2 or Layer 3 configurations from the interface. INTERFACE
2 Configure the interface for hybrid mode. portmode hybrid INTERFACE
3 Configure the interface for switchport mode.
switchport
INTERFACE
4 Add the interface to a tagged or untagged VLAN. [tagged | untagged] VLAN INTERFACE
Note: An existing switchport or port channel interface cannot be configured for Native VLAN. Interfaces
must have no other Layer 2 or Layer 3 configurations when entering the command portmode hybrid or a
message like Message 1 is displayed.
Message 1 Native VLAN Error
% Error: Port is in Layer-2 mode Gi 5/6.
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