RabbitMQ is one of the most popular Open Source message brokers. It is easy to install and is directly supported by most Linux distributions.
RabbitMQ supports several messaging protocols, including AMQP 0.9 and 1.0, STOMP, and MQTT. RabbitMQ can be used in distributed and federal configurations in order to satisfy strict high-availability requirements.
Erlang/OTP-based RabbitMQ runs on numerous operating systems and cloud environments, and provides a wide range of developer tools for most popular languages.
You can find our cheat sheet for RabbitMQ on our download page.