The OSN3500 tributary board V5_VCAIS alarm indicates that bits 5 through 7 of the V5 byte in the low-order channel VC-12 are all "1". This alarm causes abnormal transmission of single-board TU channel services. The possible reasons for alarm V5_VCAIS are as follows: Hardware failure alarms such as PLL_FAIL and CHIP_FAIL exist in the single board upstream of the service. Hardware failure of the single board of this branch circuit.

Problem Description

When a customer cleans the fiber operation of the STM-64 MSP ring composed of 10 OSN3500s in the network on a certain day, MSP inversion occurs, and at this time, some of the tributary boards in a site report V5_VCAIS and TU-AIS alarms. The customer detected no impact on user-side services, and the alarms gradually disappeared within 3 minutes. The next night, we did the MSP reversal test together with the customer, and the alarms were still there and the service was normal.

Alarm information

V5_VCAIS, TU-AIS

Processing

Upgrade the device's master control and single board to V1R7 version matching according to the conclusion. There is no abnormal alarm after the inversion test.

V5_VCAISroot cause

Check the host version of this OSN3500 device is: 5.21.13.47p01. This device comes with expansion subracks totaling 72 various veneers .

1. Check the information V5_VCAIS alarm indicates that bits 5 to 7 of the V5 byte in the low-order channel VC-12 are all "1". This alarm will affect the service.

2. Analyze the single-board black armor bb4.log and bb9.log.

3. When the number of alarms reported to the host by the single board through the single board method at the same time is too large (more than 1024), there will be alarm queue overflow, and there will be alarm queue ID overflow printing on the host, which will cause some of the alarms of the END message to be discarded (due to the reversal of multiplexed segments at that time, there will be instantaneous interruption of the service of the single board and a large number of alarms reported, but the actual service is only instantaneous interruption, and it does not affect the The actual service is just a momentary interruption, which does not affect the service and the reversal test. In addition, this network element is a very large number of single boards, alarm queue overflow possibility is very large). 4. This alarm must rely on the host of the 1-minute calibration event calibration, through the 3-minute alarm after the end of the end off (so see the reported alarms are within 3 minutes of the end of the host in the 3-minute calibration test, to filter out the filter).

5. Positioning analysis, the proposed single board with multiple packets to report alarms to the host, the single board will be packaged into 64 alarms for a packet reported to the host, and the host's message queue is the length of 1024, you can greatly improve the host's processing power, the phenomenon disappeared through the test, can be generated normally can be the end of the normal.

6. Conclusion: Because R1 ~ R6 did not modify the single-board software with multiple packets to report the version of the alarm, while the V1R7 software version has been resolved single-board multiple packets to report. Therefore, it is necessary to upgrade the single board to the V1R7 version and host matching.

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