High availability has become a key requirement of every layer in today’s technology stack. And, message queuing or message brokering software is no exception. In the past we’ve relied, like many of you, on RabbitMQ to create highly available message queues when FIFO (First-In, First-Out) was required. (Indeed, our RabbitMQ tutorial is one of our most-oft read blogs.) Often this is for ecommerce, financial services and other applications where it is important to strictly process messages only once and in the order they are published.