Create alarms for dead-letter queues using Amazon CloudWatch - Amazon Simple Queue Service
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Create alarms for dead-letter queues using Amazon CloudWatch

You can configure an alarm for any messages moved to a dead-letter queue using Amazon CloudWatch and the metric ApproximateNumberOfMessagesVisible. For more information, see Creating CloudWatch alarms for Amazon SQS metrics. After you receive an alert that messages have been sent to the dead-letter queue, you can review the messages using polling to receive the message.