Английская Википедия:Dead letter queue

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Шаблон:Short description In message queueing a dead letter queue (DLQ) is a service implementation to store messages that the messaging system cannot or should not deliver.[1] Although implementation-specific, messages can be routed to the DLQ for the following reasons:

  1. The message is sent to a queue that does not exist.[2][3]
  2. The maximum queue length is exceeded.
  3. The message exceeds the size limit.
  4. The message expires because it reached the TTL (time to live)[4]
  5. The message is rejected by another queue exchange.[5]
  6. The message has been read and rejected too many times.[6]

Routing these messages to a dead letter queue enables analysis of common fault patterns and potential software problems.[7] If a message consumer receives a message that it considers invalid, it can instead forward it an Invalid Message Channel,[8] allowing a separation between application-level faults and delivery failures.

Queueing systems that incorporate dead letter queues include Amazon EventBridge,[9] Amazon Simple Queue Service,[7] Apache ActiveMQ, Google Cloud Pub/Sub,[10] HornetQ, Microsoft Message Queuing,[2] Microsoft Azure Event Grid and Azure Service Bus,[11] WebSphere MQ,[12] Solace PubSub+,[13] Rabbit MQ,[5] Apache Kafka[14] and Apache Pulsar.[15][16]

See also

References

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