In Part 2 of this series, we’ve seen how RabbitMQ ships with tools for monitoring different aspects of your application: how your queues handle message traffic, how your nodes consume memory, whether your consumers are operational, and so on. While RabbitMQ plugins and built-in tools give you a view of your messaging setup in isolation, RabbitMQ weaves through the very design of your applications.

While the output of certain RabbitMQ CLI commands uses the term “slave” to refer to mirrored queues, RabbitMQ has disavowed this term, as has Datadog. When collecting RabbitMQ metrics, you can take advantage of RabbitMQ’s built-in monitoring tools and ecosystem of plugins. In this post, we’ll introduce these RabbitMQ monitoring tools and show you how you can use them in your own messaging setup.

RabbitMQ is a message broker, a tool for implementing a messaging architecture. Some parts of your application publish messages, others consume them, and RabbitMQ routes them between producers and consumers. The broker is well suited for loosely coupled microservices. If no service or part of the application can handle a given message, RabbitMQ keeps the message in a queue until it can be delivered.

Modern applications running on distributed systems often complicate service ownership because of their ever-growing web of microservice dependencies. This complication challenges engineers’ ability to shepherd their software through every stage of the development life cycle, as well as teams’ ability to train new engineers on the application’s architecture. With increased complexity, clarity is key for quick, effective troubleshooting and delivering value to end users.

Modern, high-scale applications can generate hundreds of millions of logs per day. Each log provides point-in-time insights into the state of the services and systems that emitted it. But logs are not created in isolation. Each log event represents a small, sequential step in a larger story, such as a user request, database restart process, or CI/CD pipeline.