Architecting Scalable MQTT Systems
Running a single MQTT broker on a Raspberry Pi is fine for a home automation project. But what happens when you need to support 10 million connected devices, process 100,000 messages per second, and maintain 99.99% uptime across continents? You hit the limits of a single broker. Scaling MQTT to industrial or global levels requires a shift in architecture, moving from a single point to a clustered broker system . Why Cluster? The Single Broker Bottleneck A single broker is a single point of failure (SPOF) and has finite limits on concurrent connections, CPU, and memory. Scaling vertically (a bigger server) hits a wall. The solution is horizontal scaling: linking multiple broker nodes into a unified cluster that acts as one logical broker to clients. How Clustering Works: The Magic Behind the Curtain In a cluster, brokers connect to each other and share client state and message routing information. The key challenge is state synchronization . How does a message pu...
