Starts a workflow when a message arrives on a subscribed MQTT topic. Ideal for IoT sensors, Zigbee2MQTT, and industrial telemetry.
When to use
- React to device state changes (availability, temperature, alarms).
- Bridge MQTT payloads into HTTP, notifications, or Modbus writes.
- On-prem brokers where cloud webhooks are not an option.
Properties
| Property | Type | Description |
|---|---|---|
| Broker Host | text | MQTT broker hostname or IP. Required. |
| Port | number | Broker port. Default: 1883. |
| Topic | text | Subscribe pattern, e.g. zigbee2mqtt/+/availability. Required. |
| Username | text | Optional broker authentication. |
| Password | password | Optional broker password. |
Outputs
Incoming message payload (JSON when parseable), topic, and broker metadata.
Notes
- On-prem only — requires network access to the MQTT broker from the Nodlyn host.
- Workflow must be Active to maintain the subscription.
- Pair with MQTT Publish for bidirectional flows.