Cautions for the Upgrade Failure on OptiX OSN 550

Summary:
During the upgrade of an Optical transmission OSN 550 earlier than V100R007C10, if the NE has a TNH2EGT1 board, the SCC switching performs repeatedly in the process of activation. After the SCC switching times out, the NE rolls back to the original version, resulting in an upgrade failure.

[Problem Description]

Fault symptoms:
During the upgrade of an OptiX OSN 550 earlier than V100R007C10, if the NE has a TNH2EGT1 board, the SCC switching performs repeatedly in the process of activation. After the SCC switching times out, the NE rolls back to the original version, resulting in an upgrade failure.

Trigger conditions:

The problem may occur if the following conditions are met. An OptiX OSN 550 with the TNH2EGT1 board is upgraded.You can get more Huawei transmission board from Huawei network product distributor

• The source version and target version of the upgrade are both earlier than V100R007C10.

Identification method:
This problem can be identified if the following conditions are met.

• The source version and target version of the upgrade are both earlier than V100R007C10.
• The OptiX OSN 550 is inserted with an TNH2EGT1 board.
• The following information is recorded in the black box errlog reset record:

ExcptErr: taskname=004tSQMProcess, pc=4981b7ac, SR=40009032, FaultAddr=400, DataBuff=25ce364.

[Root Cause]

The software causes an abnormal alarm detecting task during the upgrade reset of the THN2EGT1 board. Therefore, the active SCC board resets and the package loading state rolls back to the state of activating the standby board. After the standby SCC board reset, the SCC tries to activate the THN2EGT1 board, which again triggers abnormal board tasks and active SCC board reset. In this condition, the status of package loading switches between activating the SCC and activating the THN2EGT1 board. As a result, the activation task times out and the upgrade fails.