H3C S7500 Series Operation Manual page 181

Operation Manual – QinQ
H3C S7500 Series Ethernet Switches
[SwitchA-vlan10] quit
[SwitchA] interface Ethernet2/0/2
[SwitchA-Ethernet2/0/2] port link-type trunk
[SwitchA-Ethernet2/0/2] port trunk permit vlan 10
# Enable QinQ for Ethernet 2/0/1 of Switch A. Add the port to VLAN 10.
[SwitchA-Ethernet2/0/2] quit
[SwitchA] interface Ethernet2/0/1
[SwitchA-Ethernet2/0/1] port access vlan 10
[SwitchA-Ethernet2/0/1] vlan-vpn enable
[SwitchA-Ethernet2/0/1] quit
2) Configure Switch B.
# Configure Ethernet 2/0/3 and Ethernet 2/0/4 of Switch B as trunk ports. Add the two
ports to VLAN 10.
<SwitchB> system-view
[SwitchB] vlan 10
[SwitchB-vlan10] quit
[SwitchB] interface Ethernet 2/0/3
[SwitchB-Ethernet2/0/3] port link-type trunk
[SwitchB-Ethernet2/0/3] port trunk permit vlan 10
[SwitchB-Ethernet2/0/3] quit
[SwitchB] interface Ethernet 2/0/4
[SwitchB-Ethernet2/0/4] port link-type trunk
[SwitchB-Ethernet2/0/4] port trunk permit vlan 10
Note:
The following describes how a packet is forwarded from Switch A to Switch C.
As QinQ is enabled on Ethernet 2/0/1 of Switch A, when a packet from the user's
private network reaches Ethernet 2/0/1 of Switch A, it is tagged with the default
VLAN tag of the port (VLAN 10 tag) and is then forwarded to Ethernet 2/0/2.
When the packet from Ethernet 2/0/2 of Switch A reaches Ethernet 2/0/4 of Switch B
in the public network, it is forwarded to Ethernet 2/0/3 in VLAN 10.
The packet is forwarded from Ethernet 2/0/3 of Switch B to the user network on the
other side and reaches Ethernet 2/0/2 of Switch C. Switch C forwards the packet in
VLAN 10 to its Ethernet 2/0/1. As Ethernet 2/0/1 is an access port, the outer VLAN
tag of the packet is stripped off and the packet is restored the original one.
It is the same case when a packet travels from Switch C to Switch A.
After the configuration, the networks connecting Switch A and Switch C can receive
packets from each other.
1-4
Chapter 1 QinQ Configuration