Huawei SLD64 is a 2xSTM-64 Optical Interface Board with Compatibility OSN7500, OSN3500. Huawei SLD64 is available in the following functional versions: N1SLD64 and N4SLD64.
NE A and NE B are OSN 3500. NE B is V100R008C02SPC200 version.
– SSN1SL64 board of NE A is connected to SSN4SLD64 board of NE B,
– NE B belongs to a MSP ring. NE A doestn’t belong to this ring.
When fiber cut occurs between NE C and NE D of MSP ring, the NE C reports R_LOF and MS_AIS alarms, then the clock tracing changes on all MSP ring.
NE B switched to trace the new line clock source from NE G, however NE A reports LTI and CLK_NO_TRACE_MODE alarms appeared on NE A and it lost synchronization source.
We analyze the problem of LTI and CLK_NO_TRACE_MODE alarms according to the next procedure:
1. Review clock configuration on OSN 3500 NE A. Check J0s and optical power. No R_LOS alarm was reported. The configuration was correct, fiber connections were correct, optical power mets the requirements.
2. Delete the clock configuration on NE A. Create it again. The alarms persists.
3. Check clock source switching on NE A. Forced it to the line board, the alarms were cleared. But when Clear, the NE A traced to the internal clock and alalrms appeared again.
4. Cold reset the line board on NE A. The alarms persist.
5. Replace line board in NE A. The alarms persist.
6. Cold reset cross-connection board on NE A. The alarms persist.
7. Switch cross-connection boards on NE A. The alarms persist.
The alarms were cleared only when fiber cut was fixed.
When fiber cut occurs the clock tracing changes on all MSP ring, including NE B. It switched to trace the new line clock source from NE G. But also sends a DNU (Do Not Use) message on SLD64 board (to NE A).
The NE A trace the clock signal from NE B, and receives the DNU message. The NE A also sends DNU message on SL64 board (to NE B) and lost synchronization source.
The problem is caused by SLD64 board on NE B, due to software issues in 5.21.18.50p01 (V100R008C02SPC200) version. This problem was solved in V100R008C02SPC500 and V100R010C03SPC100 later versions.
The final solution consist on upgrade OSN 3500 NE B to V100R008C02SPC500 or V100R010C03SPC100 or higher versions.If you have installed SSN4SLD64 board on OSN 3500 V100R008C02SPC200, the NEs connected to this board could lost synchronization source when the NE changes the tracing clock.
It’s recommended to upgrade NE to V100R008C02SPC500 or V100R010C03SPC100 or higher version.
Thunder-link.com now have all versions of huawei SLD64 board,including :
SSN1SLD64(I-64.1,LC)
SSN1SLD64(S-64.2b,LC)
SSN4SLD64(I-64.1,LC)
SSN4SLD64(S-64.2B,LC)
All are original new and have very competitve price. The highest discount reach 98% off list price. Do not hesitate, just come to visit www.thunder-link.com; or email for inquire: sales@thunder-link.com
Comments are closed