Operation Manual – QinQ-BPDU Tunneling
H3C S3610&S5510 Series Ethernet Switches
Chapter 1 QinQ Configuration
1-5
Caution:
z
An inner VLAN tag corresponds to only one outer VLAN tag. If you want to change
an outer VLAN tag, you must delete the old outer VLAN tag configuration and
configure a new outer VLAN tag.
z
By default, you should assign a selective QinQ-enabled port to the VLAN which the
uplink traffic belongs to, that is, the CVLAN, so that the port can receive and process
the uplink traffic normally. Alternatively, you can disable VLAN check on the port.
For detailed information about VLAN check, refer to the
VLAN
module.
1.4 Configuring MAC Address Synchronization
When a selective QinQ-enabled port receives a packet, it learns the source MAC
address of the packet, stores the MAC address in the MAC address table of the inner
VLAN of the packet, tags the packet with an outer VLAN tag, and then sends the packet
to the uplink port for transmission. When the returned packet arrives at the uplink port,
the switch searches the MAC address table of the outer VLAN for the packet’s downlink
MAC address but can find none. As a result, the switch will broadcast the packet in the
outer VLAN. This not only consumes bandwidth resources but also brings about
security risks in the network.
To address the problem, the S3610&S5510 series provide the MAC address
synchronization function to synchronize MAC address entries between inner and outer
VLANs. By performing inner-to-outer synchronization on the downlink port and
outer-to-inner synchronization on the uplink port, the switch can unicast rather than
broadcast the packet returning to the uplink port.
Follow these steps to configure MAC address synchronization:
To do...
Use the command...
Remarks
Enter system view
system-view
—
Enter Ethernet port view
interface interface-type
interface-number
—
mac-mirroring
index
src-vlan
source-vlan-list
dest-vlan
destination-vlan-id
Configure MAC address
synchronization
mac-mirroring
index
src-vlan
source-vlan-id
dest-vlan
destination-vlan-list
Required
Disabled by default