NE5000E--NE80E--S8505--NE40--user network segment
The NE80E’s interface connected to an NE40 is set to the user termination mode and is configured with sub-interfaces for both QinQ and dot1q VLAN tag termination. The QinQ sub-interface is connected to other users on a MAN and the Layer 3 dot1q sub-interface is connected to the NE40. A static route to the user network segment of the NE40 is configured on the NE80E. The NE80E uses OSPF to advertise this static route. An S8505 between the NE80E and NE40 transparently transmits Layer 2 packets. The NE40 is configured with a default static route for receiving packets from the NE80E.
When the preceding problem occurs, the NE80E’s QinQ sub-interface can ping the NE40 and the NE40’s user network segment. The NE5000E can ping the NE80E’s QinQ sub-interface directly connected to the NE40, but cannot ping the NE40E’s user network segment.
The learned routes and the outbound interfaces are correct on the NE5000E, NE80E, and NE40.
2. The NE80E uses the address of the interface connected to the NE40 as the source address and pings the NE40. The ping is successful. The NE5000E uses the address in the same network segment as the NE80E and pings the NE40’s user network segment. The ping fails. The possible cause is that the NE80E does not forward the ping packets to the user network segment.
3. Traffic statistics are collected. Based on the analysis, the NE80E does not forward the NE5000E’s packets to the sub-interface connected to the NE40.
4. If the control-vid vid dot1q-termination command is used on the NE80E, the VID value needs to be the same as the VLAN ID. This allows the sub-interface to function as a network gateway.
Possible causes are as follows:
An IP address conflict or other problems occur. As a result, the NE5000E or NE40 learn incorrect routes.
2. The NE80E does not forward data of the user network segment.
In V300R006, if the control-vid vid dot1q-termination command is used on the NE80E, the VID value must be the same as the VLAN ID to allow the sub-interface to function as a network gateway. Other types of sub-interfaces have no such a requirement.