This guide explains how to install Mosquitto Broker for MQTT communication on a Linux Ubuntu VM (Virtual Machine) using Digital Ocean. Running an MQTT Mosquitto Broker in the cloud allows you to connect several ESP32/ESP8266 boards and other IoT devices from anywhere using different networks as long as they have an Internet connection. You’ll also learn how to connect your ESP boards to the cloud MQTT broker using Arduino IDE.
We have a guide that introduces you to the MQTT protocol. MQTT stands for Message Queuing Telemetry Transport. It is a lightweight publish and subscribe system where you can publish and receive messages as a client. Read What is MQTT and how it works.
An MQTT broker is primarily responsible for receiving all MQTT messages, filtering the messages, decide who is interested in each message and then, publishing the messages to all subscribed clients.
There are several brokers you can use. In our Home Automation projects and tutorials we use the popular Mosquitto MQTT Broker. It is easy to install, configure and use.