Delivery Guarantees
At-most-once, at-least-once, and exactly-once — when to use each and how they work end-to-end.
- 1At-Most-Once DeliveryMessages may be lost but are never duplicated. Achieved by: acks=0 (no confirmation), or acks=1 without retries. The pro…
- 2At-Least-Once DeliveryMessages are never lost but may be duplicated. Achieved by: acks=all, retries=MAX, enable.idempotence=false. If the netw…
- 3Exactly-Once Semantics (EOS)Messages are delivered and processed exactly once, end-to-end. Producer-side EOS: enable.idempotence=true prevents dupli…
Knowledge check
Q1.What combination achieves exactly-once producer semantics within a session?
Q2.At-least-once delivery requires what from consumers?
Q3.What does isolation.level=read_committed do?