Overview

This section summarizes best practices of RocketMQ in common scenarios. Each practice is given a description and procedure.

**Table 1** RocketMQ best practices
Best Practice	Description
Deduplicating Messages Through Message Idempotence	To avoid service exceptions caused by repeated message consumption, RocketMQ consumers receive a message and perform idempotent processing based on a unique key. This document contains the concept, scenario, and implementation of idempotent messages.
Classifying Messages with Topic and Tag	RocketMQ classifies services by topic or tag. Topics are superior to tags. This document describes how to filter messages by topic and tag.
Ensuring Subscription Consistency	Messages may be consumed repeatedly or missed due to disordered consumption logic caused by inconsistent subscriptions. This document describes the concept, principle, and implementation of subscription consistency.
Handling Message Accumulation	This document describes the causes and solutions of message stack.
Configuring Message Accumulation Monitoring	This document describes how to configure RocketMQ alarm rules on Cloud Eye. Cloud Eye can monitor the real-time instance running status and key service metrics, and notify exceptions in time. In this way, you are aware of risks in the production environment.
Suggestions on Using DMS for RocketMQ Securely	This document describes security best practices of using RocketMQ. It aims to provide a standard guide for overall security capabilities.