By default any message picked up from a queue by a consumer is removed (acknowledged), but you can configure the exchange so that it waits for an ACK from the c

By default any message picked up from a queue by a consumer is removed (acknowledged), but you can configure the exchange so that it waits for an ACK from the consumer before removing the message. This gives the consumer the ability to return the message to the queue, but is dangerous because Rabbit will never stop waiting on the consumer to respond.