VLAN-VPN Configuration Example 121
Configuration Procedure Perform the following procedure to configure switches A and C.
1Configure Switch A and Switch C.
As the configuration performed on Switch A and Switch C is the same, configuration
on Switch C is omitted.
aConfigure Ethernet1/0/2 port of Switch A to be a VLAN-VPN uplink port and add it
to VLAN 10. Set the TPID value of the port to 0x9100.
<SwitchA> system-view
System View: return to User View with Ctrl+Z.
[SwitchA] vlan 10
[SwitchA-vlan10] quit
[SwitchA] interface GigabitEthernet1/0/2
[SwitchA-Ethernet1/0/2] vlan-vpn tpid 9100
[SwitchA-Ethernet1/0/2] port link-type trunk
[SwitchA-Ethernet1/0/2] port trunk permit vlan 10
[SwitchA-Ethernet1/0/2] vlan-vpn uplink enable
bConfigure GigabitEthernet1/0/1 port of Switch A to be a VLAN-VPN port and add
it to VLAN 10.
[SwitchA] interface GigabitEthernet1/0/1
[SwitchA-Ethernet1/0/1] port access vlan 10
[SwitchA-Ethernet1/0/1] vlan-vpn enable
[SwitchA-Ethernet1/0/1] quit
2Configure Switch B
Because Switch B comes from another vendor, the commands involved may differ
from those for S5500 switches. So only the operations are listed, as shown below:
■Configure Ethernet3/1/1 and Ethernet3/1/2 ports of Switch B to be trunk ports.
■Add the two ports to VLAN 10.
The following describes how a packet is forwarded from Switch A to Switch C.
■As the Ethernet1/0/1 port of Switch A is a VLAN-VPN port, when a packet reaches
Ethernet1/0/1 port of Switch A, it is tagged with the default VLAN tag of the port
(VLAN 10, the outer tag) and is then forwarded to Ethernet1/0/2 port.
■Because Ethernet1/0/2 port is a VLAN-VPN uplink port with a TPID of 0x9100,
Switch A changes the TPID value in the outer VLAN Tag of the packet to 0x9100
and forwards the packet to the public network.
■The packet reaches Ethernet3/1/2 port of Switch B. Switch B sends the packet to
its Ethernet3/1/1 port to enable the packet being forwarded in VLAN 10.
■The packet is forwarded from Ethernet3/1/1 port of Switch B to the network on
the other side and enters Ethernet1/0/2 port of Switch C, Switch C sends the
packet to its Ethernet1/0/1 port by forwarding the packet in VLAN 10. As
Ethernet1/0/1 port is an access port, Switch C strips off the outer VLAN tag of the
packet and restores the original packet.
It is the same case when a packet travel from Switch C to Switch A.
After the configuration, the networks connecting Switch A and Switch C can receive
data packets from each other.