Description of the problem

Huawei OSN3500 equipment network element C, using two sets of STM-1 optical ports with two 155M SNCP rings (ring one and ring two), ring one has M1000V3 equipment network element A, ring two has M1000V3 equipment network element B, A and B have 2M tributary services opened to the central computer room network element D, respectively, and the 2M tributary board ports 1 and 2 of the Huawei OSN3500 network element. For details, see the attached figure, "Networking Diagram 1." On a certain day, the fiber-optic cable of the Ring 1 and Ring 2 lines is cut, and after the end of the day, there are no abnormal alarms or performance events for the transmission equipment, but the switching side reflects the interruption of the base station services on Ring 1 and Ring 2.

Processing

1. Huawei OSN3500 device service configuration error;

2, there are loopbacks that should not be there;

3, fiber connection error;

Root cause

Misconnection of optical fibers

Solution

1、Check the business configuration, there is no problem, and the line cut has not changed the transmission service, so exclude the business configuration error;

2. There is no alarm on the transmission side, which means that there is no problem on the transmission side of the 2M service between A, B and D, and there should be no problem in the 2M port connection between A, B, D and the switching equipment;

3. The 2M ports of A, B and D all do external loopback, and the switching side reflects normal, so it can be ruled out that it is the problem of 2M docking between transmission and switching;

4, A network element 2M tributary board service within the loopback, in the D station corresponding 2M port hanging table test, found that there is a frame out of step alarm;

5, in the D station will correspond to the B station business to activate, the results of the A station branch board PS inversion occurred, and the A station business back to normal, suspected fiber connection error;

6, by modifying the J0 byte check A, B and network element C between the connecting fiber, found that the C network element ring one and ring two each have a pair of fibers and network management equipment on the connecting fiber relationship is inconsistent, misplaced each other, see the attached figure "Network Diagram";

7, modify the wrong way to connect the fiber, troubleshooting.

Recommendations and Summary

1. The absence of alarms and performance events on transmission does not mean that there is no problem on the transmission side;

2, involving the end of the transmission side of the fiber optic cable cut to carefully check the new equipment docking relationship, be sure to ensure that and the original docking relationship is consistent;

3, when dealing with faults diligently use the meter, the results reflected in the meter shall prevail.

The related technical information in this chapter and the SDH equipment troubleshooting process are collected and organized by Shenzhen Optical Transmission Network Technology Company Limited ( www.opticaltrans.com), please retain! Our company specializes in the sale of Huawei SDH optical transmission equipment, SDH transmission equipment.