What is an MQTT to Kafka bridge?

An MQTT to Kafka bridge is a component that consumes messages from an MQTT broker and forwards them to a Kafka cluster. This allows IoT devices that communicate via MQTT to have their data processed by backend systems and big data platforms that use Kafka as a high-throughput data bus.

Why use EMQX for MQTT to Kafka integration?

EMQX combines MQTT device connectivity with SQL processing and Kafka integration. Configure a Kafka Sink for outgoing data or a Kafka Source for incoming events. Buffer settings, retry behavior, and monitoring help you manage delivery for your workload.

Can EMQX transform data before sending it to Kafka?

Yes. EMQX includes a powerful SQL-based rule engine that allows you to process data in-flight. You can filter, reformat, enrich, and transform MQTT message payloads and metadata before they are published to a Kafka topic, ensuring the data is in the correct format for downstream consumers.

How are MQTT and Kafka different?

MQTT is a lightweight publish/subscribe protocol for connecting devices, including those with limited resources or unreliable networks. Apache Kafka is a distributed event streaming platform for processing and storing high-throughput data streams. EMQX bridges the two so MQTT device events can feed Kafka-based applications.

What happens if Kafka is temporarily unavailable?

EMQX buffers outgoing messages while its Kafka integration reconnects. Buffer mode and capacity determine how messages are retained: disk buffering can survive an EMQX node restart, while memory buffering cannot. Older messages may be discarded when the buffer fills, so size the buffer for your expected outage and monitor delivery metrics.

EMQX KAFKA INTEGRATION

Stream MQTT data into Kafka

Ingest millions of MQTT messages from IoT devices and stream them directly into Apache Kafka for real-time analytics.

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Overview

MQTT and Kafka: Better together for IoT data streaming

MQTT connects your IoT devices. Kafka streams their data to downstream systems. Together, they form a backbone for large-scale IoT data architectures.

MQTT: The Standard for IoT Connectivity

MQTT is a lightweight, efficient protocol designed to connect millions of constrained and unreliable devices at the edge. It excels at collecting data from sensors and machines.

Massive device fan-in
Low network bandwidth usage
Handles unreliable networks

Kafka: The Standard for Data Streaming

Kafka is a distributed streaming platform designed for high-throughput, fault-tolerant data pipelines. It excels at processing and distributing large data streams to backend enterprise systems.

High-throughput data pipelines
Fault-tolerant data storage
Connects to big data systems

Architecture

MQTT to Kafka architecture

Connect millions of IoT devices to Kafka streams through a decoupled EMQX architecture.

Sensors

Vehicles

Devices

Factories

Gateways

EMQX Enterprise

Real-Time MQTT

Pub/Sub Messaging

Rule Engine

Kafka Bridge

Kafka Ecosystem

Apache Kafka

Confluent

Amazon MSK

Downstream

Analytics

Data Lake

Stream Processing

Capabilities

Built for reliable, high-throughput IoT data pipelines

Filter, buffer, and route MQTT data into Kafka with delivery metrics for ongoing monitoring.

High-Throughput Ingestion

Stream MQTT messages to Kafka with synchronous or asynchronous writes. Tune the pipeline for your message volume, latency needs, and Kafka capacity.

Kafka Sink guide

Buffered Data Delivery

Buffer messages during temporary Kafka interruptions. Choose a buffer mode and capacity for your workload, and monitor failed or dropped messages.

Buffer settings

Real-time Data Transformation

Use a powerful, SQL-based rule engine to filter, enrich, and transform MQTT messages into the ideal format before they are published to Kafka topics.

Rule SQL reference

Flexible Topic Mapping

Easily map MQTT topics to specific Kafka topics, with dynamic routing based on topic, client ID, or message payload content.

Topic mapping guide

Bi-directional Data Bridging

Use a Kafka Sink to send MQTT data to Kafka. Configure a separate Kafka Source to consume backend events and republish them to MQTT devices.

Kafka Source guide

Operational Monitoring

Get real-time metrics and detailed logs on data throughput, message latency, and the health of the Kafka integration.

Monitoring guide

Customer story

SAIC Volkswagen powers connected vehicles with MQTT and Kafka

In its published case study, SAIC Volkswagen reported over 100,000 connected vehicles. EMQX bridges vehicle data into Kafka for asynchronous processing.

Connected vehicles: 100k+
Data integration: Kafka

Read the customer story

How it works

From MQTT to Kafka in 3 steps

Configure your MQTT to Kafka bridge with the EMQX rule engine and flow designer.

1
Connect Devices
Connect millions of IoT devices and sensors to EMQX using the MQTT protocol.
2
Process & Transform
Use the rule engine to filter and transform MQTT data into the desired format for Kafka.
3
Stream to Kafka
Reliably stream the processed data into your designated Kafka topics.

Ecosystem

Connect to Kafka and other streaming platforms

Connect to Kafka-compatible services, plus platforms with dedicated EMQX integrations.

Use cases

Built for real-time IoT applications

Connect data-intensive applications, from connected cars to smart factories.

Connected Vehicles

Ingest telematics data from millions of vehicles via MQTT and stream it to Kafka for real-time fault diagnosis, driver behavior analysis, and predictive maintenance.

Explore connected vehicles

Smart Manufacturing

Collect data from thousands of factory-floor sensors and PLCs. Stream it to Kafka to feed MES, SCADA, and machine learning models for quality control and operational intelligence.

Explore smart manufacturing

Fleet Telemetry

Collect and stream high-frequency telematics data from commercial vehicle fleets into Kafka for real-time tracking, route optimization, and operational analytics.

Explore fleet telematics

Resources

Explore EMQX and Kafka integration

FAQ

Frequently asked questions

Build your MQTT to Kafka pipeline

Talk to our team about building a scalable, reliable, and secure MQTT to Kafka bridge with EMQX.

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