Dead-Letter Queue Explosion

A schema/content change is causing a large share of incoming events to fail parsing and land in the dead-letter queue, and a reprocessor has begun replaying DLQ contents back into the consumer at the same time. Events in the DLQ represent real customer activity (orders, updates, notifications) that must eventually be processed exactly once — side effects must never be applied twice, and any event that is dropped is gone for good. Diagnose why events are failing, stop the bleeding, and bring the backlog back to a safe, durable state.

Difficulty

Senior

Expected Time

~18 min

Category

Messaging & Streaming