Practical Guide to Troubleshooting Lost SMPP DLRs

Lost DLRs lead to inaccurate business status statistics; furthermore, some overseas carriers inherently experience delays of several hours in delivering receipts.

Key Troubleshooting Areas

1. SMPP Connection Keep-Alive

• Configure heartbeat packets to prevent disconnection due to inactivity.


• Avoid frequent SMPP connection re-establishment to prevent receipt mismatches.




2. DLR Data Retention



• Store the mapping between `submit_sm` message IDs and DLR IDs.


• Maintain comprehensive logs for reconciliation and issue diagnosis.




3. Application-Side Processing Recommendations



• Optimize callback logic to prevent DLR accumulation and subsequent loss.


• Distinguish between carrier-induced delays and actual DLR loss.


• Regularly track DLR arrival rates and promptly investigate any anomalies.

Maintain comprehensive logs to quickly identify root causes of anomalies and ensure the accuracy of business status statistics.