Amazon SQS supports dead-letter queues (DLQ)

▪ Messages can't be processed because of a variety of possible issues.

▪ Example; User places a web order with a particular product ID, but the product ID is deleted.

Code fails and displays an error, and the message with the order request is sent to a dead-letter

queue.

▪ The main task of a dead-letter queue is to handle the lifecycle of unconsumed messages.

▪ A dead-letter queue lets you set aside and isolate messages that can't be processed correctly

to determine why their processing didn't succeed.

▪ Setting up a dead-letter queue

▪ Configure an alarm for any messages moved to a dead-letter queue.

▪ Examine logs for exceptions that might have caused messages to be moved to a dead-letter queue.

▪ Analyze the contents of messages moved to a dead-letter queue.

▪ Determine whether you have given your consumer sufficient time to process messages.

https://docs.aws.amazon.com/AWSSimpleQueueService/latest/SQSDeveloperGuide/sqs-dead-letter-queues.html