Description of the problem

The cross-board service recovery time of Huawei OSN3500 GXCSA-B2 reaches about 8 minutes, which should be about 4 minutes according to the customer's requirements and the access test results at that time.

Processing

1. Issue the :cfg-backup-bdcfg command to the cross-board to save the newly configured service information into FLASH. Then power down and test, the result is about 4 minutes.

2. After the service, wait for 1 hour for the platform to save the newly configured service information into FLASH, and then power down and test. The result is about 4 minutes.

Root cause

Validation of the data in the laboratory of the Regional Department Training Center:

Step 1 Customer validates environmental information:

SSN2PQ1A02 software version is 6.55

N3SL16A05 software 7.59

SSN3GSCC02 5.21.18.50P01

SSN1GXCSA02 9.63

Step 2 Build the environment to reproduce:

Use the customer test veneer to build the environment, configure the test service, and hang the table for testing. Observe the process of network element power-down and power-up, and find that the service is not restored when the cross single board and service single board are up normally. When the master control is up normally, the service is resumed. Check the business interruption time is 8 minutes, this interruption time is exactly N3GSCC master control board normal up time. The problem is reproduced.

Step 3 According to the phenomenon of speculation:

According to the observed phenomenon, the service is not restored after the cross-single board and the service single board get up normally, which indicates that the cross-single board does not restore the saved cross-matrix information correctly. The possible reasons are:

The cross-matrix information is not saved in FLASH;

The cross-matrix information is not saved correctly;

Cross-matrix information was not recovered correctly;

Step 4 Verify that the cross-matrix information is not saved correctly:

Issue the :cfg-backup-bdcfg command to the cross veneer to let the cross save the cross-matrix information to FLASH. then the network element is powered down and powered up and tested. when the cross veneer and the service veneer are up normally. the service is restored immediately. We can see that the reason for this problem is that the cross-board does not save the cross-matrix information to FLASH.

Step 5 Cross-board replacement test:

Replace the GXCS-B2 veneer with GXCS veneer, and perform the same test, and find the same phenomenon. It means that this problem is not an individual version problem, but a generalized problem.

Step 6 troubleshooting code:

Through the troubleshooting code, we found that by issuing the command :cfg-backup-bdcfg, the corresponding function of the platform will call the product overload function to save the cross-matrix information into FLASH. When this command is not issued, the platform has a timed task (1 hour) to save the cross-matrix information into FLASH, that is, the platform will save the cross-matrix information into FLASH once every 1 hour.

Step 7 Problem Cause:

The cause of this problem is that after configuring a new service, the platform has not saved the newly configured service information into FLASH, and after power down and up, the cross cannot recover the cross-connection information of the new service from FLASH, and the service will be interrupted all the time. Until the master control board since the cross-board application to start, the master control board to re-issue the configuration information to the cross and business board, business resumed.

Recommendations and Summary

1, after the configuration of new services, the platform has not yet saved the newly configured service information into FLASH, after power down, the cross can not recover the cross-connection information of the new service from FLASH, and the service will be interrupted all the time. Until the main control board since the cross-board application to start, the main control board to re-issue configuration information to the cross and business board, business recovery.

2, confirmed by the R & D, this problem does not belong to the hardware or software defects, there is no version plan. However, the working principle of this single board needs to be clarified so as not to cause confusion or misunderstanding.

3、After R&D confirmed that the same problem exists for all cross boards.

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