Configure a Tagged Port to Discard Untagged Frames

Configure a tagged port to discard all untagged packets so that the frame is not classified into the default VLAN for the port.

Procedure

Enter GigabitEthernet Interface Configuration mode:

enable

configure terminal

interface GigabitEthernet {slot/port[/sub-port][-slot/port[/sub-port]][,...]}

Note

If the platform supports channelization and the port is channelized, you must also specify the sub-port in the format slot/port/sub-port.
Configure a tagged port to discard untagged frames:

untagged-frames-discard [port {slot/port[/sub-port][-slot/port[/sub-port]][,...]}]
Discard a tagged frame on an untagged port:

tagged-frames-discard [port {slot/port[/sub-port][-slot/port[/sub-port]][,...]}] enable
Untag the default VLAN on a tagged port:

untag-port-default-vlan [port {slot/port[/sub-port][-slot/port[/sub-port]][,...]}] enable

Configure a tagged port to discard untagged frames:

Switch(config-if)#untagged-frames-discard port 1/1

Discard a tagged frame on an untagged port:

Switch(config-if)#tagged-frames-discard port 1/1 enable

Untag the default VLAN on a tagged port:

Switch(config-if)#untag-port-default-vlan port 1/2 enable

Use the data in the following table to use optional parameters with the untagged-frames-discard command.


Variable	Value
{slot/port[/sub-port][-slot/port[/sub-port]][,...]}	Identifies the slot and port in one of the following formats: a single slot and port (slot/port), a range of slots and ports (slot/port-slot/port), or a series of slots and ports (slot/port,slot/port,slot/port). If the platform supports channelization and the port is channelized, you must also specify the sub-port in the format slot/port/sub-port.