x-death

AMQP 0-9-1 metadata used to detect poison messages.

Definition

When a message is dead-lettered, RabbitMQ enriches its headers with an x-death array holding, per queue/reason pair, a count, the reason (rejected, expired, maxlen), the originating queue and a timestamp. A consumer reads this counter to decide when to abandon a message after N rejections — the broker-side poison-message detection mechanism.

Origin

Defined by RabbitMQ's dead-lettering extension to the AMQP 0-9-1 protocol (official "Dead Letter Exchanges" documentation). The JMS-side equivalent is the JMSXDeliveryCount header in the Jakarta Messaging specification.

Example in context

x-death: [{count: 3, reason: 'rejected', queue: 'invoices', exchange: '', time: ...}]

Related terms

• Poison message — what x-death helps spot.
• DLQ — queue fed on dead-lettering.