There are three OptiX OSN 3500 NEs: NE A, NE B, and NE C. The NEs are connected through the SSN2SL64 boards in slots 8 and 11 into a ring. The NEs run OptiX OSN 3500 V100R006C01B01d. The T2000 version is V200R004C01B01c. The NEs perform ECC communication by using IP. The PC of T2000 is connected through a router to the two gateway NEs: NE A and NE B. For how to configure IP over ECC, see the Guide to Deploy the IP over DCC Feature on the OptiX SDH Products. On the network, the PC of T2000 can ping all the NEs through NE A but cannot ping the NEs through NE B. For the test configurations, see the IP over DCC Test Configurations.
1. Check the connection between the router and NE B in this manner. Substitute a PC for NE B. Then, ping that PC from the PC of T2000. The ping succeeds. Therefore, the connection between the router and NE B works properly.
2. Check the router configurations. It is found that the router has two routes but that only one of the routes is valid. In other words, the router supports only one route. For details on the router configurations, see the IP over DCC Test Configurations.
ip route 0.0.0.0 0.0.0.0 126.96.36.199
ip route 0.0.0.0 0.0.0.0 188.8.131.52
Only the route ip route 0.0.0.0 0.0.0.0 184.108.40.206 is valid. The route ip route 0.0.0.0 0.0.0.0 220.127.116.11 is invalid. Therefore, the routes are switched frequently. The engineers suspect that this is the cause of the problem. The R&D team, however, suggests that both routes be deleted. Therefore, the engineers delete the two routes from the router. The problem, however, persists.
3. Check the IP over ECC configurations. It is found that the IP over ECC configurations are correct.
4. Replace the GSCC on NE B with the GSCC on NE A and then perform the relevant configurations. The problem, however, persists. The T2000 can ping all the NEs through NE A but cannot ping the NEs through NE B.
5. Check whether OSPF is enabled on the LAN interface. It is found that OSPF is disabled on the LAN interface on each NE. Enable the OSPF protocol on the LAN interface. The problem is solved. To query and enable the OSPF protocol on the LAN interface, run the following commands:
1. The router or the cable between the router and NE B fails, and therefore the connection between the router and NE B has a problem.
2. There is a router configuration error.
3. There is an IP over ECC configuration error.
4. The GSCC on NE B fails, and therefore the relevant configurations do not take effect.
5. The OSPF is disabled on the LAN interface.
To communicate by using IP over DCC, NEs need to enable OSPF on the LAN interface. If the OSPF protocol is disabled on the LAN interface, routes cannot be set up properly between the NEs and the router. As a result, the router cannot ping the gateway NEs or the other NEs on the network.