Summary:
Creep occurs on SD585 soldered balls of some cross-connect boards of OptiX OSN 3500 so these boards repeatedly reset, fail to work, and report BD_STATUS alarms.
[Problem Description]
Trigger conditions:
There is a possibility that this problem occurs as a result of long-term exposure of the boards involved to high temperature.

Symptom:
1. Boards are reset repeatedly and fail to work.
2. NEs may report BD_STATUS alarms or COMMUN_FAIL alarms on cross-connect boards. System control boards may report BIOS_STATUS alarms on cross-connect boards.
Identification method:
The problem can be identified if the following two conditions are met:
1. The boards are manufactured in Feb 2010, Apr 2010, May 2010, Jul 2010, Aug 2010, or Mar 2011.
2. The cross-connect boards are repeatedly reset and fail to work. The board BOMs are found in the attached Board Delivery Information.

[Root Cause]
The SD585 chip radiator uses the thick spring, which applies high levels of stress to the chip. The soldered ball of the SD585 chip may deform and short-circuit as a result of long-term exposure to high temperature. Therefore, the board repeatedly reset and fail to work.
[Impact and Risk]
1. Services are not influenced because of the 1+1 protection scheme is configured on the cross-connect boards. When a cross-connect board is faulty, services are switched over to the other cross-connect board.

2. In extra situations, both cross-connect boards configured in the 1+1 protection scheme become faulty in a short time. As a result, the NE fails to work and services are interrupted.
[Measures and Solutions]
Recovery measures:
Replace the faulty cross-connect board.
Solution:
Replace the faulty boards.
[Rectification Instructions]

Replace the faulty boards.
SSN1SXCSA02 (03030KBM) boards are out of production, so replace SSN1SXCSA02 boards with SSN1SXCSA01 (03030DKF) when filling in an electric process application for board rectification in batches. The two kinds of boards can be mixedly inserted or completely replace each other. Active and standby boards of the same type are recommended.