Description of the problem

The fiber optic transmission trunk network, consisting of six OADMs and several OSN6800s of OLAs, with service configurations that are all centralized ODU1 SNCP services. In the optical line 1 + 1 transformation of the network, an OSN6800 network element 0 subrack (with seven OSN6800 slave racks) of the single board was pulled out and inserted into some of the new expansion of the single board, it was found that the 1/7/8 slot single board can not be on-line, and then pulled out the new expansion of the single board after the 0 subrack is only left 17/18-11SCC, 16-SC2, the network management on the Slot 2 has been displaying a 12 OBU that cannot be brought online (M40V was plugged into slot 1 before expansion, and no OBUs have been plugged into slot 2 after expansion), and the command line query cfg-get-phybd shows that there is a 2-OBU veneer, but there is no veneer in the actual physical slot.

BD_NOT_INSTALLED with parameters: para[0]=0x0,para[1]=0x2,para[2]=0xff,para[3]=0xff,para[4]=0xff

Processing

The problem can be analyzed in two parts: a. In the case of no physical single board in slot 2, the network management still has an OBU physical single board; b. The subrack cannot recognize the newly inserted single board. The possible causes of these two failures are as follows:

1, other network element information string network, caused by slot 2 can not remove the OBU;

2, the subrack AUX failure, causing slot communication abnormalities;

3, the subframe SCC hardware, database, software version and other reasons for abnormal causes of the single board can not be online;

4, 2-slot motherboard failure, may cause 7/8 slot can not recognize the single board, as well as 2-slot in place line has been pulled up, the single board can not be deleted.

Root cause

Problems with the subrack motherboard

Solution to the problem

The process of troubleshooting possible causes one by one is as follows:

1, serial network exclusion: 0 sub-frame and 1 sub-frame of the network cable disconnected, the network element is still monitoring normal, and then unplug the sub-frame 16-SC2, that is, the sub-frame is completely independent. With the command line query 2 slot is still in --- can rule out other network elements crosstalk network problems.

2, the sub-frame AUX failure: replacement of the sub-frame AUX --- query 2 slots still exist;

3, the sub-frame SCC failure: a, the original sub-frame of the 17 and 18 slots SCC one by one for network management hard reset, query 2 slots still exist.

b. Dial out the 17-slot SCC single board, unplug the 18-SCC, query the 2-slot no physical single board; after restoring the two SCCs, insert the VA4 in the 2-slot.

After restoring two SCCs, insert VA4 in slot 2 and unplug it again, the physical single board still exists in slot 2; continue to dial out the 17-slot SCC and unplug the 18-SCC, and query that there is no physical single board in slot 2.

c. After replacing the SCC and inserting the database for clearing, there is still a physical veneer in slot 2.

d. From this, SCC database and hardware problems can be ruled out

4, 2-slot motherboard failure: a, replace the new sub-frame, and use the new AUX and the old sub-frame of the SCC, power on, 14/15/16 slots and can not recognize the physical board.

board. At this point, the failure became even more strange, in order to further determine the root cause of the problem, we did further testing on the new subrack.

b. Three scenarios were tested based on the new subframe:

I. New subrack, new AUX, new SCC, this scenario slot 14/15/16 cannot recognize the single board;

II, new subrack, old AUX, new SCC, this scenario slot 14/15/16 can recognize the single board;

III, new subrack, old AUX, old SCC, this scenario slot 14/15/16 can recognize the single board;

Through the above tests, it can be determined that the new AUX is also a faulty single board, resulting in the problem is not completely solved, replaced back to the old AUX single board after the solution.

So far, the final solution to this problem is to replace the sub-frame solution, the root cause is the sub-frame motherboard problems, pulling up the 2-slot in the line, so that as long as the insertion of the slot of the veneer are shown to have always been a physical veneer. In addition, the failure of the 2-slot will also cause other slots to irregularly appear on the board can not be on the line, resulting in other slots of the board can not be recognized.

Suggestion and Summary

Subrack motherboard problems may cause multiple failure phenomena that momentarily make it difficult to quickly localize to a hardware or software problem. Therefore, when encountering communication problems, it is important to troubleshoot each possible cause one by one, and multiple combinations should be taken into account, so that new problems can be avoided to be introduced when dealing with old failures.

The related technical information in this chapter and the SDH equipment troubleshooting process are collected and organized by Shenzhen Optical Transmission Network Technology Company Limited (www.opticaltrans.com), please retain! Our company specializes in the sale of Huawei SDH optical transmission equipment,SDH transmission equipment.