On a network, the 18-SCC board on an OptiX OSN 6800 NE reports the TEMP_OVER alarm. The alarm cannot be cleared. Run the cfg-get-scc-temperature:bid command to query the actual temperature of the 18-SCC board. The query result indicates a temperature of 22.3°C, which is in the normal range.
The 18-SCC board reports the TEMP_OVER alarm as follows: 210440 TEMP_OVER MJ start 2010-10-28 05:25:21 None SA NEW_BOARD board=18;para=0x2;
1. Run the cfg-get-scc-temperature:bid command to query the actual temperature of the 18-SCC board. The query result indicates a temperature of 22.3°C, which is in the normal range.
2. Run the alm-del-curdata:num command to clear this alarm. The alarm, however, is generated again.
3. Perform cold resets on the active and standby SCCs. The alarm, however, still cannot be cleared.
4. After analysis, R&D personnel believe the SCC is faulty and suggest replacing the 18-SCC board. After the 18-SCC board is replaced, the alarm still cannot be cleared, even the time when the alarm is generated does not change.
5. Remove both the active and standby SCCs and insert them according to R&D personnel's suggestion. The alarm persists.
6. Run the alm-get-bdalm-new command to query which board reports the TEMP_OVER alarm. The query result indicates that the 118-SCC board reports the alarm.
7. Perform a cold reset on the 118-SCC board. The TEMP_OVER alarm is cleared.
At last, the causes of this problem are determined as follows:
If the TN11SCC board reads the chip temperature during temperature register update, it obtains an invalid value. As a result, the SCC board will report the TEMP_OVER alarm transiently. LOS alarms are not generated on a board. The SCC on the slave subrack, however reports that LOS alarms are generated on this board.
Each of the following reasons may make the SCC report the TEMP_OVER alarm:
1. Ambient temperature is higher than the upper limit.
2. The fan board is faulty.
3. The alarm is incorrectly reported due to SCC failure.
1. Run the alm-get-bdalm-new command to query which board reports the alarm if encountering similar problems. 2. Enhance the anti-jitter alarm function.