Summary: The clock chips used on some TN55N02 and TN55TOX boards of Huawei OSN product OptiX OSN 8800 NEs have design defects. As a result, the failure rate of the chips is 5% after they are in service for 2 years. In the case of a clock chip failure, services on these boards will be interrupted and cannot be restored even after you remove and reinsert or perform a cold reset on the boards.
[Problem Description]
Trigger conditions:
The chip failure rate is 5% within 2 years. The chip failure rate is proportional to the service period but is irrelevant to application scenarios.
Symptom:
On the transmission faulty board, a Hard_Bad alarm is reported and cannot be cleared and services are interrupted.
Identification method:
1. Check the barcodes of the boards against the attachment. If the barcodes are included in the attachment which provided by the official website, you can determine that the boards are at risk of a clock chip failure.
2. If the previously described symptom occurs on a TN55TOX01 or TN55NO201 board, you can determine that the board is at risk of a clock chip failure.
[Root Cause]
The clock chip has design defects. As a result, the TN55NO2 and TN55TOX boards have 5% failure rate within 2 years.
[Impact and Risk]
OptiX OSN 8800: On a board with a defective clock chip, a Hard_Bad alarm is reported and services are interrupted. The services cannot be restored even after you remove and reinsert or perform a cold reset on the board. The chip failure rate is 5% within 2 years and is proportional to the service period.
[Measures and Solutions]
Recovery measures
Replace the boards with a defective clock chip.
Solutions:
Replace the boards with a defective clock chip.