Mosquitto
Open-source MQTT message broker for IoT messaging.
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Self-host it
Run the open-source version on your own infrastructure.
What is Mosquitto?
Eclipse Mosquitto is an open-source message broker that implements the MQTT (Message Queuing Telemetry Transport) protocol, enabling lightweight, efficient communication between devices in IoT ecosystems. It supports MQTT versions 5.0, 3.1.1, and 3.1, making it ideal for resource-constrained environments like low-power sensors, microcontrollers, and embedded systems. Developed under the Eclipse Foundation’s iot.eclipse.org project, Mosquitto provides a publish/subscribe model where devices can send (publish) or receive (subscribe) messages through a central broker. Its lightweight design allows it to run on devices from single-board computers to servers, addressing challenges like limited bandwidth and power constraints in IoT deployments. Developers, system integrators, and IoT project teams use Mosquitto to streamline device communication, ensuring reliable data transmission in scenarios ranging from smart home systems to industrial automation. By abstracting the complexities of MQTT, it reduces the overhead for developers to implement messaging in distributed systems.
How it works
How Mosquitto works — see the article below for details on this iot tool.
How to use it
- 1Use the Mosquitto tool to complete your task.
- 2Use the Mosquitto tool to complete your task.
- 3Use the Mosquitto tool to complete your task.
- 4Use the Mosquitto tool to complete your task.
What it can do
- mqtt broker
Use cases
Assumptions and limitations
Assumptions
- source: https://github.com/eclipse-mosquitto/mosquitto
- license: EPL-2.0 — free to use
- privacy: Self-hosted — you control your data
Limitations
- Self-hosted — requires setup, maintenance, and your own infrastructure.
- Proprietary license — not open source; check Mosquitto's terms before commercial use.
- Relies on an external source (github.com); availability depends on that service.
- Focused on the iot category: Open-source MQTT message broker for IoT messaging..
Understanding the result
Open-source MQTT message broker for IoT messaging.
Tool details
- Clearly flagged when a network request is needed.
- No account, no sign-up, and no tracking of your content.
- Powered by (MIT).
- Built with
- (eclipse-mosquitto/mosquitto)
- License
- MIT
- Runs locally
- No — requires a network request
- Verification
- Not yet verified
- Input
- Query
- Output
- Text
Built with eclipse-mosquitto/mosquitto. OpenToolVault provides the discovery and browser interface while crediting the original project maintainers.
- Built with
- License
- MIT
Open-source project
OpenToolVault is an independent directory. We are not affiliated with or endorsed by this project.
References
- / — GitHub Repository
Upstream project · GitHub
- EPL-2.0 License
Upstream project
Frequently asked
What is Mosquitto and what does it do?
Mosquitto is an open-source MQTT message broker that facilitates communication between devices using the publish/subscribe model. It enables devices to exchange data efficiently by acting as an intermediary that routes messages between publishers and subscribers. Mosquitto supports MQTT versions 5.0, 3.1.1, and 3.1, making it suitable for IoT applications where lightweight, low-bandwidth communication is critical. It is used by developers to connect sensors, actuators, and other edge devices to cloud platforms or local networks, ensuring reliable message delivery even in resource-limited environments.
How does Mosquitto implement the MQTT protocol?
Mosquitto implements MQTT by acting as a broker that manages message routing between clients. When a device (client) publishes a message, Mosquitto forwards it to all subscribed clients matching the topic. It supports Quality of Service (QoS) levels to ensure message delivery reliability and includes features like last will messages for client status tracking. The broker handles network protocols, authentication, and message persistence, allowing developers to focus on application logic. Its use of TCP/IP and WebSocket protocols ensures compatibility with diverse IoT architectures.
How do I set up a Mosquitto broker on my local machine?
To set up Mosquitto, first download the binaries or source code from the official website. On Linux, use a package manager like apt (e.g., `sudo apt install mosquitto`), or build from source with cmake. After installation, configure the broker via the `mosquitto.conf` file, specifying options like listening ports, persistence, and authentication. Start the broker with `mosquitto -c /path/to/mosquitto.conf`. Test it using command-line tools: publish a message with `mosquitto_pub -h localhost -t test -m 'Hello'` and subscribe with `mosquitto_sub -h localhost -t test` to verify connectivity.
How does Mosquitto compare to alternatives like RabbitMQ or AWS IoT Core?
Mosquitto differs from RabbitMQ and AWS IoT Core by prioritizing lightweight design and minimal resource usage. RabbitMQ is a general-purpose message broker supporting AMQP, which is more feature-rich but heavier for IoT. AWS IoT Core is a cloud-based service offering managed MQTT, scalability, and integration with AWS ecosystems, but at a cost. Mosquitto excels in edge computing and local deployments, while alternatives like MQTT.js (JavaScript) or Eclipse Hono (for cloud-native IoT) cater to specific use cases. Mosquitto’s open-source license (EPL-2.0) also makes it more accessible for on-premises or custom IoT solutions.
What should I do if Mosquitto fails to start?
Common issues include port conflicts (default port 1883), incorrect configuration files, or missing dependencies. Check if port 1883 is blocked by a firewall using `netstat -tuln` or `lsof -i :1883`. Verify the configuration file (`mosquitto.conf`) for syntax errors with `mosquitto -c /path/to/config -v`. Ensure all required libraries are installed, especially on Linux. If using a custom configuration, ensure the `pid_file` and `data_dir` paths are valid. For detailed logs, run `mosquitto -c /path/to/config -v` to capture errors during startup.