8-8
Catalyst 6500 Series Switch Software Configuration Guide—Release 8.7
OL-8978-04
Chapter 8 Configuring IEEE 802.1Q Tunneling and Layer 2 Protocol Tunneling
Configuring Layer 2 Protocol Tunneling on the Switch
This example shows how to specify a Layer 2 protocol on a port and verify the configuration:
Note
You can specify more than one protocol type at a time. In the CLI, separate protocol types with a space.
Console> (enable)
set port l2protocol-tunnel 3/15 cdp enable
Layer 2 protocol tunneling enabled for CDP on port 3/15.
Port 3/15 trunk mode set to off.
Console> (enable)
set port l2protocol-tunnel 3/15 cdp disable
Layer 2 protocol tunneling disabled for CDP on port 3/15.
Console> (enable)
set port l2protocol-tunnel 3/15 cdp stp vtp enable
Layer 2 protocol tunneling enabled for CDP STP VTP on port 3/15.
Port 3/15 trunk mode set to off.
Console> (enable)
show l2protocol-tunnel statistics 3/15
Tunneling CoS is set to 5.
Port CDP Frames Encap CDP Frames De-encap
------------------------ -------------------- --------------------
3/15
97465
94434
Port STP Frames Encap STP Frames De-encap
------------------------ -------------------- --------------------
3/15
67465
34434
Port VTP Frames Encap VTP Frames De-encap
------------------------ -------------------- --------------------
3/15
1212
1213
Console> (enable)
Configuring Layer 2 Protocol Tunneling on Trunk Ports
Layer 2 protocol tunneling on trunks allows third-party vendors’ equipment to interoperate with the
Catalyst 6500 series switch in service-provider networks. Layer 2 protocol tunneling makes control
protocol PDUs such as STP, CDP, and VTP, transparent to the service provider cloud when passing traffic
through trunk ports. Because of some interoperability issues with other vendors’ switches, you cannot
achieve true transparent LAN service (TLS) or enable 802.1Q tunneling when using third-party
switches. In earlier releases, Layer 2 protocol tunneling was available on access ports only.
Note
The service providers should not allow customers to connect directly to trunks on which Layer 2 protocol
tunneling is enabled.
Follow the guidelines in the
“Layer 2 Protocol Tunneling Configuration Guidelines” section on page 8-7
.
Additionally, you cannot configure 802.1Q tunneling on the trunk ports; however, 802.1Q tunneling can be
tunneled through the trunk ports.
Note
If you have a mixed network environment that is using both 802.1Q tunneling and Layer 2 protocol
tunneling, you must double-tag packets in order to interoperate with third-party equipment.