Cisco Systems 15327 Configuring IEEE 802.1Q Tunneling

9-4
Ethernet Card Software Feature and Configuration Guide, R7.2
January 2009
Chapter 9 Configuring IEEE 802.1Q Tunneling and Layer 2 Protocol Tunneling
Configuring IEEE 802.1Q Tunneling
Configuring IEEE 802.1Q Tunneling
This section includes the following information about configuring IEEE 802.1Q tunneling:
• IEEE 802.1Q Tunneling and Compatibility with Other Features, page 9-4
• Configuring an IEEE 802.1Q Tunneling Port, page 9-4
• IEEE 802.1Q Example, page 9-5
Note By default, IEEE 802.1Q tunneling is not configured on the ML-Series.
IEEE 802.1Q Tunneling and Compatibility with Other Features
Although IEEE 802.1Q tunneling works well for Layer 2 packet switching, there are incompatibilities
with some Layer 2 features and with Layer 3 switching:
• A tunnel port cannot be a routed port.
• Tunnel ports do not support IP access control lists (ACLs).
• Layer 3 quality of service (QoS) ACLs and other QoS features related to Layer 3 information are
not supported on tunnel ports. MAC-based QoS is supported on tunnel ports.
• EtherChannel port groups are compatible with tunnel port s as long as the IEEE 802.1Q
configuration is consistent within an EtherChannel port group.
• Port Aggregation Protocol (PAgP) and Unidirectional Link Detection (UDLD) Protocol are not
supported on IEEE 802.1Q tunnel ports.
• Dynamic Trunking Protocol (DTP) is not compatible with IEEE 802.1Q tunneling because you must
manually configure asymmetric links with tunnel ports and tr unk ports.
• Loopback detection is supported on IEEE 802.1Q tunnel ports.
• When a port is configured as an IEEE 802.1Q tunnel po rt, spanning tree bridge protocol data unit
(BPDU) filtering is automatically disabled on the interface.
Configuring an IEEE 802.1Q Tunneling Port
Beginning in privileged EXEC mode, follow these steps to configure a port as a n IEEE 802.1Q tunnel
port:
Command Purpose
Step 1 Router# configure terminal Enters global configuration mode.
Step 2 Router(config)# bridge
bridge-number
protocol bridge-protocol
Creates a bridge number and specifies a protocol.
Step 3 Router(config)# interface fastethernet
number
Enters the interface configuration mode and the interface to be
configured as a tunnel port. This should be the edge port in the
service-provider network that connects to the customer switch. Valid
interfaces include physical interfaces and port-channel logical
interfaces (port channels 1 to 64).