Summary:
A 10G OTU board reports an OTU2_LOF alarm at a low probability on the Huawei WDM side during the running. When this alarm is reported, services are interrupted and the alarm persists.
[Problem Description]
Trigger conditions:
This problem has no external trigger conditions, and occurs at a 1% probability during normal running.
Symptom:
An OTU2_LOF alarm is reported and persists during the normal running of a 10G OTU board.
Identification method:
1. An OTU2_LOF alarm is reported on the board and persists. In addition, services are interrupted.
2. After a self-loop is performed on the IN port and OUT port of the peer board, an OTU2_LOF alarm is reported or the pre-FEC BER of the board is in the range of 1E-3 to 1E-11; however, no exception occurs after a WDM-side software loopback is performed.
3. According to the board manufacturer information, boardtype contains SSX2T2TM and the time specified by Manufactured is earlier than April 2010.
The following describes the procedure for querying Huawei board manufacturer information:
Step 1 From the main menu of the NMS, choose Report > Board Manufacturer Information Report.
Step 2 On the Board Manufacturer Information Report tab in the window that is displayed, view the board manufacturer information, especially the fields that are highlighted in the following figure.
[Root Cause]
Air and moisture enter the SiN passivation layer and erode the electrode on the FET grid of the SSX2T2TM module, causing a decrease of output amplitude of the drive on the SSX2T2TM module. As a result, the drive on the SSX2T2TM module fails.
[Impact and Risk]
If the drive on the local board fails, an OTU2_LOF alarm will be reported on the peer board and persist. In addition, services will be interrupted.
[Measures and Solutions]
Recovery measures:
Replace the local board.(click here for more Huawei transmission equipment)
Workarounds:
No workaround is available.
Comments are closed