Kafka Consumer Lag Troubleshooting and Offset Recovery: A Practical Guide

When Consumer Lag accumulates in a Kafka cluster, first export the original offsets, then use dry runs and `–from-file` to control resets and rollbacks; the Consumer Group must be `Empty` or `Dead`. Recovery succeeds only when offsets match across all Partitions, the Lag trend meets the objective, no abnormal errors appear in logs, and business metrics are normal.