KB.15.15

Table 33 Impacts of QinQ configurations on other switch features (continued)

Impacts of QinQ configurations and allowed operationsSwitch feature

In QinQ S-VLAN mode:

• Provider (S-VLAN) spanning tree is supported—both provider-network ports and customer-network

ports will receive/transmit provider STP BPDUs.

• Customer (VLAN) spanning tree tunneling is supported on S-VLAN interfaces—customer-network

or provider-network ports will tunnel customer STP BPDUs through the appropriate S-VLAN.

In QinQ mixed VLAN mode:

• Stacking is supported only on C-VLANs. The device does not advertise itself (using the stack

discovery protocol) in the S-VLAN space.

In QinQ S-VLAN mode:

• Stacking discovery protocol frames will not be sent out of customer-network ports; similarly,

any stacking discovery protocol frames received on customer-network ports will be dropped.

Stacking

In QinQ mixed vlan or S-VLAN modes:UDLD

• UDLD frames received on udld-disabled customer network ports will be dropped. However, if

the customer-network port is udld-enabled, it can peer with a customer device.

• UDLD frames received on udld-disabled provider network ports will be re-forwarded out of

other udld-disabled provider network ports on the same VLAN.

• UDLD re-forwarding in the C-VLAN space (QinQ disabled or mixed VLAN mode) will remain

unaltered.

In QinQ S-VLAN mode:

• udp-bcast-forward is not supported on provider core devices.

udp-bcast-forward

In QinQ mixed VLAN mode:unknown-vlans

• GVRP (learn and disabled modes) not supported on S-VLAN ports.

• A C-VLAN port that has GVRP enabled will need to disable it before it can be added to S-VLANs.

In QinQ mixed VLAN mode:

• S-VLANs cannot be configured as voice-VLANs.

Voice VLANs

In QinQ mixed VLAN or S-VLAN modes:

• VRRP is not supported on S-VLANs.

VRRP

About QinQ 341