1. This log show CRAM of the FPGA fail, and detect by SEU monitoring, then record the information in the log.
2. As the patch solution, About the SEU detection function, In the Patch Release Notes of PTN960 SPH102.
3. From the log, confirm KNGE308a-PTN01z slot 4 receive direction there are ISIS HELLO packet drop count.
4. R&D found out the PDU header length should be 0x1B, but it actual receive 0x1A. So we consider the packet have been changed unexpected. And the fault bit is bit23, it have been fixed as “0” all the time.
5. Analyze the OAM packet，if bit23 fixed as “0”, then the DMAC will be change 0x4B to 0x4A，then it will drop when the MAC not match in MPLS forward module later.
6. SEU fault cause slot 4 EX1 change the packet, and then in the master control board can’t match the MAC it will drop the packet, so it report MPLS_TUNNEL_LOCV alarm.