Help Center/ Distributed Message Service for RabbitMQ/ User Guide/ Managing Messages/ Configuring RabbitMQ Delayed Messages
Updated on 2025-11-20 GMT+08:00
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Configuring RabbitMQ Delayed Messages

Delayed messages enter queues for consumers to consume after a specified delay, instead of being received by consumers immediately after being sent.

Notes and Constraints

The delay exchange function is available only in RabbitMQ AMQP-0-9-1.

Configuring Delayed Messages

You can implement delayed messages in any of the following ways:

  • Setting a delay exchange: Messages sent to a delay exchange carry the same delay time by default.
  • Setting the message delay time: Each message can be set with different delay time.
  • Setting the time to live and dead letter queue: Expired messages are automatically routed to the dead letter queue.

Messages sent to a delay exchange carry the same delay time by default.

The following example shows how to configure a delay exchange on a Java client:

Map<String, Object> args = new HashMap<String, Object>();
args.put("x-delayed-type", "direct");
channel.exchangeDeclare("exchange", "x-delayed-message", true, false, args);

Each message can be set with different delay time.

The following example shows how to set the message delay time on a Java client.

final HashMap<String, Object> headers = new HashMap<>();
            headers.put("x-delay", 10000);
            final AMQP.BasicProperties.Builder properties = new AMQP.BasicProperties().builder().headers(headers);
            // publish a batch of messages to the main exchange
            for (int i = 0; i < messageCount; i++) {
                channel.basicPublish(exchangeName, routingKey, properties.build(),
                    ("x-delayed-message-" + i).getBytes());
            }

Expired messages are automatically routed to the dead letter queue.

The following example shows how to set the time to live and dead letter queue on a Java client:

channel.queueDeclare("dlq", false, false, false, null);
channel.exchangeDeclare("dlx", BuiltinExchangeType.DIRECT);
channel.queueBind("dlq", "dlx", "rt");

HashMap<String, Object> arguments = new HashMap<>();
arguments.put("x-dead-letter-exchange", "dlx");
arguments.put("x-dead-letter-routing-key", "rt");
arguments.put("x-message-ttl", 5000);
channel.exchangeDeclare("normal", BuiltinExchangeType.DIRECT);       
channel.queueDeclare("normal", true, false, false, arguments);
channel.queueBind("normal", "normal", "key");
channel.basicPublish("normal", "key", null, "ttl".getBytes());
Parent Topic: Managing Messages