Azure IoT Hub Integration
Azure IoT Hub Integration connects ThingsBoard to Azure IoT Hub over MQTT as one registered device. It receives the cloud-to-device messages addressed to that device, and an uplink data converter transforms each message into device or asset data, including telemetry and attributes. ThingsBoard can also publish downlink messages to the hub as that device.
Use Azure IoT Hub Integration when:
- A backend application sends data to ThingsBoard as cloud-to-device messages through Azure IoT Hub.
- One hub connection must deliver data for many ThingsBoard devices: the converter sets the target device for each message.
- An Azure-side consumer must receive ThingsBoard data from the hub’s built-in events endpoint.
Architecture
Section titled “Architecture”- Receive data. A backend application, the Azure portal, or the Azure CLI sends a cloud-to-device message to the integration’s device identity. The integration is subscribed to
devices/{deviceId}/messages/devicebound/#and receives it. - Decode the payload. The uplink converter identifies the target device or asset from the payload and extracts attributes and telemetry.
- Process the message. ThingsBoard processes the converted data through the Rule Engine. If Allow create devices or assets is enabled, ThingsBoard can create an entity that does not exist yet.
- Send downlink data (optional). The Rule Engine passes a message to the integration. The downlink converter encodes it, and the integration publishes it to
devices/{deviceId}/messages/events/as a device-to-cloud message.
Prerequisites
Section titled “Prerequisites”- Access to ThingsBoard Cloud with integrations enabled for your tenant.
- Permission to create integrations and data converters.
- An Azure account with an active subscription and permission to create an IoT hub and register devices.
- Outbound TCP port
8883open from the ThingsBoard server to*.azure-devices.net.
Configure Azure IoT Hub
Section titled “Configure Azure IoT Hub”Create the hub and the device identity in the Azure portal.
Create an IoT Hub
Section titled “Create an IoT Hub”- In the Azure portal, click + Create a resource, search for IoT Hub, and click Create.
- On the Basics tab, select or create a Resource group, enter a globally unique IoT hub name (for example,
tb-iot-hub), and choose a Region. - Adjust the Networking and Management tabs if your environment requires it, then click Review + create and Create.
- When the deployment finishes, click Go to resource.
- On the Overview page, copy the Hostname, for example
tb-iot-hub.azure-devices.net.
For tiers and limits, see Create an IoT hub.
Register a Device
Section titled “Register a Device”- In the hub, go to Device management ⇾ Devices and click + Add device.
- Enter a Device ID, for example
tb-bridge-01. - Keep Authentication type set to Symmetric key and Auto-generate keys selected.
- Click Save.
- Open the device and copy its Primary key.
To authenticate with X.509 certificates instead, see Create and manage device identities and Credentials.
You now have the values for the integration:
| Value | Example | Source |
|---|---|---|
| Hostname | tb-iot-hub.azure-devices.net |
Hub Overview page |
| Device ID | tb-bridge-01 |
Device you registered |
| SAS Key | Primary key | Device details page |
Set Up Azure IoT Hub Integration
Section titled “Set Up Azure IoT Hub Integration”Create the uplink converter, assign it to a new Azure IoT Hub integration, and send a test message.
Create the Uplink Data Converter
Section titled “Create the Uplink Data Converter”The uplink converter receives each message as a byte array plus its topic, resolves the target device, and returns its telemetry and attributes. Azure IoT Hub Integration uses the Generic converter: you write the decoder in TBEL or JavaScript. For converter types and the full decoder reference, see Uplink data converter.
This guide uses the sample payload that ThingsBoard provides for Azure IoT Hub converters, with a recent timestamp:
{ "deviceId": "8F4A2C6D", "deviceType": "Packing machine", "temperature": 25.5, "pressure": 1013.25, "vibration": { "x": 0.02, "y": 0.03, "z": 0.015 }, "location": { "latitude": 37.7749, "longitude": -122.4194, "altitude": 10 }, "timestamp": "2026-10-14T10:30:00Z", "status": "ALARM", "alarms": [ { "type": "temperature", "severity": "high", "message": "Temperature exceeds threshold." }, { "type": "vibration", "severity": "critical", "message": "Excessive vibration detected." } ], "metadata": { "version": 1, "batteryLevel": 100, "batteryStatus": "Charging", "manufacturer": "Example corporation" }}-
Go to Integrations ⇾ Data converters and click + Add data converter ⇾ Create new converter.
-
Converter type — keep Uplink.
-
Integration type — select Azure IoT Hub.
-
Name — enter a name, for example
Azure IoT Hub Uplink Converter. -
Main decoding configuration — the editor opens with the default Azure IoT Hub template. Replace it with the decoder below. The decoder maps measurements and state to telemetry and static device properties to attributes. It also reads
timestamp,location, andvibrationwhen the payload carries them. The editor opens in TBEL; use the TBEL / JS toggle to switch to JavaScript.var data = decodeToJson(payload);var deviceName = data.deviceId != null ? data.deviceId : "Device A";var deviceType = data.deviceType != null ? data.deviceType : "default";// ISO 8601 timestamp; fall back to server time.var ts = data.timestamp != null ? new Date(data.timestamp).getTime() : Date.now();// Static device properties become attributes.var attributes = {};if (data.location != null) {attributes.latitude = data.location.latitude;attributes.longitude = data.location.longitude;attributes.altitude = data.location.altitude;}if (data.metadata != null) {attributes.version = data.metadata.version;attributes.manufacturer = data.metadata.manufacturer;}// Measurements and state become telemetry.var telemetry = {temperature: data.temperature,pressure: data.pressure,status: data.status,receivedAlarms: data.alarms};if (data.vibration != null) {telemetry.vibrationX = data.vibration.x;telemetry.vibrationY = data.vibration.y;telemetry.vibrationZ = data.vibration.z;}if (data.metadata != null) {telemetry.batteryLevel = data.metadata.batteryLevel;telemetry.batteryStatus = data.metadata.batteryStatus;}return {deviceName: deviceName,deviceType: deviceType,attributes: attributes,telemetry: {ts: ts,values: telemetry}};var data = decodeToJson(payload);var deviceName = data.deviceId != null ? data.deviceId : "Device A";var deviceType = data.deviceType != null ? data.deviceType : "default";// ISO 8601 timestamp; fall back to server time.var ts = data.timestamp != null ? new Date(data.timestamp).getTime() : Date.now();// Static device properties become attributes.var attributes = {};if (data.location != null) {attributes.latitude = data.location.latitude;attributes.longitude = data.location.longitude;attributes.altitude = data.location.altitude;}if (data.metadata != null) {attributes.version = data.metadata.version;attributes.manufacturer = data.metadata.manufacturer;}// Measurements and state become telemetry.var telemetry = {temperature: data.temperature,pressure: data.pressure,status: data.status,receivedAlarms: data.alarms};if (data.vibration != null) {telemetry.vibrationX = data.vibration.x;telemetry.vibrationY = data.vibration.y;telemetry.vibrationZ = data.vibration.z;}if (data.metadata != null) {telemetry.batteryLevel = data.metadata.batteryLevel;telemetry.batteryStatus = data.metadata.batteryStatus;}var result = {deviceName: deviceName,deviceType: deviceType,attributes: attributes,telemetry: {ts: ts,values: telemetry}};// Convert the byte array to a string.function decodeToString(payload) {return String.fromCharCode.apply(String, payload);}// Convert the byte array to a JSON object.function decodeToJson(payload) {return JSON.parse(decodeToString(payload));}return result;To adapt:
- Device name in another field — replace
data.deviceId, for example withdata.serialNumber. - Optional fields — remove the
location,vibration,status, oralarmsmappings your devices never send. - Other telemetry — add keys to
telemetry, for examplehumidity: data.humidity. - Other device properties — add them to
attributes, for examplemodel: data.model. - Update-only keys — for Azure IoT Hub, ThingsBoard pre-fills the Update only keys list in Advanced decoding parameters with
manufacturer,receivedAlarms,status,batteryLevel,batteryStatus, andversion. These keys are stored only when their value changes. Edit the list to match your keys.
- Device name in another field — replace
-
Click Test decoder function and check the result (see Test the Decoder).
-
Click Add.
Decoder Inputs
The decoder signature is function decoder(payload, metadata): object | object[].
| Variable | Type | Content |
|---|---|---|
payload |
byte array | The message body. |
metadata |
{[key: string]: string} |
topic — the topic the message arrived on: devices/{deviceId}/messages/devicebound/ followed by the message’s property bag. Also integrationName and the key–value pairs from the integration’s Metadata field. |
Built-in helpers:
| Function | Result |
|---|---|
decodeToJson(payload) |
Parses the bytes as JSON and returns an object. |
decodeToString(payload) |
Converts the bytes to a UTF-8 string. |
toFlatMap(obj, excludeKeys, flatNested) |
TBEL only. Returns a flat key–value map of obj, skipping excludeKeys. With flatNested set to true, nested objects become dot-separated keys. |
For field renaming, nested values, and non-JSON payloads, see Common scripting patterns.
Test the Decoder
Click Test decoder function below the editor. Replace the content of Payload with the sample payload. Click Test. The Output panel shows:
{ "deviceName": "8F4A2C6D", "deviceType": "Packing machine", "attributes": { "latitude": 37.7749, "longitude": -122.4194, "altitude": 10, "version": 1, "manufacturer": "Example corporation" }, "telemetry": { "ts": 1791973800000, "values": { "temperature": 25.5, "pressure": 1013.25, "status": "ALARM", "receivedAlarms": [ { "type": "temperature", "severity": "high", "message": "Temperature exceeds threshold." }, { "type": "vibration", "severity": "critical", "message": "Excessive vibration detected." } ], "vibrationX": 0.02, "vibrationY": 0.03, "vibrationZ": 0.015, "batteryLevel": 100, "batteryStatus": "Charging" } }}ts is the payload’s timestamp, 2026-10-14T10:30:00Z, in milliseconds.
Check that deviceName is set and telemetry holds the expected keys. If the output is empty or shows an error, fix the decoder and test again.
Create the Integration
Section titled “Create the Integration”- Go to Integrations ⇾ Integrations and click + Add integration.
- Basic settings:
- Integration type — select Azure IoT Hub.
- Name — keep the default or enter your own.
- Enable integration and Allow create devices or assets — keep both on, so the device is created on its first uplink.
- Click Next.
- Uplink data converter:
- Click Select existing and choose
Azure IoT Hub Uplink Converter. - Alternatively, click Create new to write a decoder here.
- Click Next.
- Click Select existing and choose
- Downlink data converter:
- Click Skip. Add a downlink converter later if you need to send data to the hub.
- Connection:
- Hostname — enter the hub hostname, for example
tb-iot-hub.azure-devices.net. - Device ID — enter
tb-bridge-01. - Credentials — keep Shared Access Signature and paste the device’s primary key into SAS Key.
- Topic filters — replace the default
#withdevices/tb-bridge-01/messages/devicebound/#. - Leave the other parameters at their defaults. See Connection Settings for details.
- Hostname — enter the hub hostname, for example
- Click Add.
Connection Settings
Section titled “Connection Settings”| Parameter | Description |
|---|---|
| Hostname | Hub hostname, {hub-name}.azure-devices.net. Find it on the hub’s Overview page. |
| Device ID | The device identity the integration connects as. It is also the MQTT client ID. |
| Credentials | Shared Access Signature (default) or PEM. See Credentials. |
| Topic filters | Subscriptions, each with a Topic and QoS (0 or 1; IoT Hub does not support QoS 2). Default: # with QoS 0. Use devices/{deviceId}/messages/devicebound/# — IoT Hub delivers cloud-to-device messages only on this topic. The # is required because the hub appends a property bag to the topic. |
| Execute remotely | Runs the integration as a separate process outside the ThingsBoard cluster, for example in a network with access to Azure. ThingsBoard generates an Integration key and Integration secret for it. See Remote Integration. |
Advanced settings
| Parameter | Default | Description |
|---|---|---|
| Protocol version | MQTT 3.1.1 | The only version available. |
| Max bytes in message | 32368 |
Maximum size of an incoming message, in bytes (1–256,000,000). |
| Description | — | Free-text description. |
| Metadata | — | Key–value pairs added to the metadata of every message from this integration. |
The integration always connects over TLS on port 8883 with a clean session. It does not offer Check connection: check the integration status after you add it.
Credentials
Section titled “Credentials”| Type | Fields |
|---|---|
| Shared Access Signature | SAS Key — the device’s primary or secondary key. ThingsBoard builds a SAS token from it on each connection, valid for one year. CA certificate file — optional; see below. |
| PEM | X.509 authentication. Certificate file — the device certificate registered in the hub. Private key file — the key for that certificate. Private key password — only for an encrypted key. CA certificate file — optional; see below. |
Without a CA certificate file, the integration verifies the hub with the DigiCert Global Root G2 certificate, which Azure IoT Hub uses. Upload your own CA bundle only if your environment requires it. For X.509 device registration, see Authenticate identities with X.509 certificates.
Test Uplink
Section titled “Test Uplink”Send a cloud-to-device message to the integration’s device identity, then confirm that ThingsBoard decoded it and created the device.
Send a Test Uplink
Section titled “Send a Test Uplink”Send the sample payload without timestamp. The decoder then uses the current server time; with a fixed timestamp, the data would fall outside the recent time windows of your dashboards as time passes.
-
In the hub, go to Device management ⇾ Devices and open
tb-bridge-01. -
Click Message to Device.
-
Paste the payload into Message Body:
{"deviceId": "8F4A2C6D","deviceType": "Packing machine","temperature": 25.5,"pressure": 1013.25,"vibration": {"x": 0.02,"y": 0.03,"z": 0.015},"location": {"latitude": 37.7749,"longitude": -122.4194,"altitude": 10},"status": "ALARM","alarms": [{"type": "temperature","severity": "high","message": "Temperature exceeds threshold."},{"type": "vibration","severity": "critical","message": "Excessive vibration detected."}],"metadata": {"version": 1,"batteryLevel": 100,"batteryStatus": "Charging","manufacturer": "Example corporation"}} -
Click Send Message.
Install the azure-iot extension, then run:
az iot device c2d-message send \ --hub-name tb-iot-hub \ --device-id tb-bridge-01 \ --data '{"deviceId":"8F4A2C6D","deviceType":"Packing machine","temperature":25.5,"pressure":1013.25,"vibration":{"x":0.02,"y":0.03,"z":0.015},"location":{"latitude":37.7749,"longitude":-122.4194,"altitude":10},"status":"ALARM","alarms":[{"type":"temperature","severity":"high","message":"Temperature exceeds threshold."},{"type":"vibration","severity":"critical","message":"Excessive vibration detected."}],"metadata":{"version":1,"batteryLevel":100,"batteryStatus":"Charging","manufacturer":"Example corporation"}}'Verify the Result
Section titled “Verify the Result”- Integration events — go to Integrations ⇾ Integrations, open the integration, and click the Events tab. The uplink appears with status OK. Click
⋅⋅⋅in the Message column to see the payload. - Converter events — open
Azure IoT Hub Uplink Converterin Integrations ⇾ Data converters and click the Events tab. In shows the received payload, Out shows the decoded result, and Metadata shows the topic and integration name. - Device — go to Devices & assets ⇾ Devices. The integration has created 8F4A2C6D with the
Packing machineprofile. Open it and check the Latest telemetry tab fortemperature,pressure,status,receivedAlarms,vibrationX–vibrationZ,batteryLevel, andbatteryStatus, and the Attributes tab forlatitude,longitude,altitude,version, andmanufacturer.
Configure Downlink
Section titled “Configure Downlink”ThingsBoard publishes downlinks to the hub when the Rule Engine routes a message to the integration — for example, after a shared attribute update. Downlinks are published with QoS 1 as device-to-cloud messages from the integration’s Device ID. They reach the hub’s built-in events endpoint, where an Azure-side consumer reads them.
The topic comes from the topic value in the downlink converter’s output metadata. The integration has no fixed downlink topic, so the encoder must set topic to devices/{deviceId}/messages/events/, with the integration’s Device ID. IoT Hub closes the connection when a device publishes to any other topic. To identify the ThingsBoard device, put its name in the payload.
The downlink converter turns a Rule Engine message into the published payload. For the full encoder reference, see Downlink data converter.
Create and Assign the Downlink Converter
Section titled “Create and Assign the Downlink Converter”The encoder returns:
contentType—JSON,TEXT, orBINARY.data— the payload to publish.metadata—topic, the topic to publish to.
For RPC commands, msg.method and msg.params are available.
- Open the integration in Integrations ⇾ Integrations and click Toggle edit mode (pencil icon).
- In the Downlink data converter field, click Create new. The Downlink converter type and Azure IoT Hub integration type are preselected.
- Enter a name, for example
Azure IoT Hub Downlink Converter. - In Main encoding configuration, replace the default encoder with the one below. Replace
tb-bridge-01with your Device ID. - To record downlink events, click the debug icon next to the name, select All messages, and click Apply.
- Click Add, then Apply changes.
Encoder used in this guide (TBEL and JavaScript):
/** Encoder **/
// Prepare the downlink payload.var data = { deviceName: metadata.deviceName, ts: Date.now()};
// Map Rule Engine messages to commands.if (msgType == 'RPC_CALL_FROM_SERVER_TO_DEVICE') { // RPC request. data.method = msg.method; data.params = msg.params; data.requestId = metadata.requestId;} else if (msgType == 'ATTRIBUTES_UPDATED' || msgType == 'POST_ATTRIBUTES_REQUEST') { // Shared attribute update. data.method = 'setSharedAttributes'; data.params = msg;} else { // Other message types. data.method = 'data'; data.params = msg;}
// Return the encoded downlink payload.var result = { // Payload content type: JSON, TEXT, or BINARY (Base64). contentType: 'JSON', data: JSON.stringify(data), metadata: { // Azure IoT Hub device-to-cloud MQTT topic. topic: 'devices/tb-bridge-01/messages/events/' }};
return result;To check the encoder, click Test encoder function. Message type is already ATTRIBUTES_UPDATED. Set Message to {"temperatureUploadFrequency":60} and deviceName in Metadata to 8F4A2C6D, if they differ, then click Test. The Output shows:
{ "contentType": "JSON", "data": "{\"deviceName\":\"8F4A2C6D\",\"ts\":1755422164000,\"method\":\"setSharedAttributes\",\"params\":{\"temperatureUploadFrequency\":60}}", "metadata": { "topic": "devices/tb-bridge-01/messages/events/" }}To adapt:
- Another envelope — build
datain the structure your Azure-side consumer expects. - Payload as is — use
data: JSON.stringify(msg)and drop the branches. - Message properties — append a URL-encoded property bag to the topic, for example
devices/tb-bridge-01/messages/events/source=thingsboard. IoT Hub routing queries can filter on these properties. - Other message types — add branches for other Rule Engine message types.
Configure the Root Rule Chain
Section titled “Configure the Root Rule Chain”The encoder puts deviceName in the payload, so the rule chain first adds the device name to the message metadata.
- Go to Data processing ⇾ Rule chains and open the Root Rule Chain.
- From the Enrichment section, drag an originator fields node onto the canvas.
- Enter a Name (for example,
Retrieve device name) and map the source fields:- Name ⇾ deviceName
- Add mapped originator fields to ⇾ Metadata
- Click Add.
- Connect the message type switch node to the originator fields node with the Attributes Updated relation.
- From the Action section, drag an integration downlink node onto the canvas.
- Enter a Name (for example,
Downlink to Azure IoT Hub), select your Azure IoT Hub integration, and click Add. - Connect the originator fields node to the integration downlink node with the Success relation.
- Click Apply changes.
Test Downlink
Section titled “Test Downlink”IoT Hub does not keep a viewable history of device-to-cloud messages, so start monitoring before you trigger the downlink.
-
Start the event monitor:
Terminal window az iot hub monitor-events --hub-name tb-iot-hub --device-id tb-bridge-01 -
Go to Devices & assets ⇾ Devices, select 8F4A2C6D, and open the Attributes tab.
-
Select Shared attributes and click +.
-
Set Key to
temperatureUploadFrequency, Type to Integer, Value to60, and click Add. ThingsBoard publishes the downlink.
Verify the Downlink
Section titled “Verify the Downlink”-
Monitor output — within a few seconds, the terminal prints the event:
{"event": {"origin": "tb-bridge-01","module": "","interface": "","component": "","payload": "{\"deviceName\":\"8F4A2C6D\",\"ts\":1755422164000,\"method\":\"setSharedAttributes\",\"params\":{\"temperatureUploadFrequency\":60}}"}} -
Converter events — open the downlink converter’s Events tab. In shows the Rule Engine message, Out shows the encoded payload, and Metadata shows the topic.
Troubleshooting
Section titled “Troubleshooting”| Symptom | Cause | Fix |
|---|---|---|
| Integration is not connected | Wrong Hostname. | Copy it from the hub’s Overview page: {hub-name}.azure-devices.net. |
| Same, after authentication | Wrong Device ID or SAS Key. | Compare both with the device details in the Azure portal. Regenerate the key if unsure. |
| Same, from a private network | Outbound port 8883 is blocked. |
Open TCP 8883 to *.azure-devices.net, or use a Remote Integration. |
| Connection keeps dropping | Another client uses the same Device ID. | Register a dedicated device identity for the integration. |
| Connection drops after each downlink | The encoder’s topic is not devices/{deviceId}/messages/events/. |
Set metadata.topic in the encoder to that topic, with the integration’s Device ID. |
| No messages received | The topic filter does not match. | Use devices/{deviceId}/messages/devicebound/#, ending in #. |
| Device telemetry never arrives | Devices send device-to-cloud messages, which this integration does not receive. | Use the Azure Event Hub Integration. |
| Device not created | deviceName is empty, or Allow create devices or assets is off. |
Check Out in the converter events and the integration settings. |
| Large messages dropped | The message exceeds Max bytes in message. | Raise the limit in Advanced settings. IoT Hub limits cloud-to-device messages to 64 KB. |
| Downlink produces no event | The rule chain does not reach the integration downlink node. | Check the Root Rule Chain wiring and turn on debug mode for its nodes. |
| Downlink sent, nothing in the monitor | The monitor started after the downlink. | Start az iot hub monitor-events first, then trigger the downlink. |
To read debug events, open the integration or converter, click Events, and select an event: In is the received data, Out is the converter result, and Error holds the error text.
See Also
Section titled “See Also”- Integrations overview — how integrations, converters, uplinks, and downlinks fit together.
- Azure Event Hub Integration — read device-to-cloud telemetry from the hub’s built-in endpoint.
- Uplink data converter — decoder inputs, output format, and scripting patterns.
- Downlink data converter — encoder reference.
- Remote Integration — run the integration outside the ThingsBoard cluster.
- TBEL — built-in functions and syntax for converter scripts.
- Rule Engine — how messages are processed after decoding.
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