LevelOne FGL-2870 - Manual (Page 676)

Command Line Interface
4-310
4
• When a tunnel uplink port receives a packet from a customer, the customer
tag (regardless of whether there are one or more tag layers) is retained in the
inner tag, and the service provider’s tag added to the outer tag.
• When a tunnel uplink port receives a packet from the service provider, the
outer service provider’s tag is stripped off, and the packet passed on to the
VLAN indicated by the inner tag. If no inner tag is found, the packet is passed
onto the native VLAN defined for the uplink port.
Example
Related Commands
show dot1q-tunnel (4-311)
show interfaces switchport (4-231)
switchport dot1q-tunnel tpid
This command sets the Tag Protocol Identifier (TPID) value of a tunnel port. Use the
no form to restore the default setting.
Syntax
switchport dot1q-tunnel tpid tpid
no switchport dot1q-tunnel tpid
tpid – Sets the ethertype value for 802.1Q encapsulation. This identifier is
used to select a nonstandard 2-byte ethertype to identify 802.1Q tagged
frames. The standard ethertype value is 0x8100. (Range: 0800-FFFF
hexadecimal)
Default Setting
0x8100
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
• Use the switchport dot1q-tunnel tpid command to set a custom 802.1Q
ethertype value on the selected interface. This feature allows the switch to
interoperate with third-party switches that do not use the standard 0x8100
ethertype to identify 802.1Q-tagged frames. For example, 0x1234 is set as the
custom 802.1Q ethertype on a trunk port, incoming frames containing that
ethertype are assigned to the VLAN contained in the tag following the
ethertype field, as they would be with a standard 802.1Q trunk. Frames
arriving on the port containing any other ethertype are looked upon as
untagged frames, and assigned to the native VLAN of that port.
• All ports on the switch will be set to the same ethertype.
Console(config)#interface ethernet 1/1
Console(config-if)#switchport dot1q-tunnel mode access
Console(config-if)#