Azure Storage Queue vs Azure Service Bus for poison messages & DLQs

Question

What is the difference between Azure Queue Storage and Azure Service with regards to dead letter queues & poison messages?

How do I read the messages from those queues?

Answer 1

A poison message is a message that is sent to the queue or topic that the consuming application cannot process correctly.

Once the DeliveryCount of these messages reaches the MaxDeliveryCount of the queue/topic, they will then be classed as poison messages.

These messages will be sent to a queue called <originalqueuename>-poison.

Both support poison messages but Azure Queue Storage does not support automatic dead-lettering.

This means that while in Azure Service Bus you can set expired messages to be moved into a DLQ for later processing, messages with a TTL value that expire in Azure Storage Queue will be deleted permanently.

Otherwise, handling of messages that will "poison" the system & can never be consumed, is pretty much the same in both offerings.

Both offer a poison queue however only one offers a DLQ.