IoT Hub Emulator

Finding the Emulator

Once a hub has been created, you can find its HTTPS Endpoint on its resource page within the Locally Dashboard, and open the emulator from the command line using:

The IoT Hub Emulator

Within the IoT Hub Emulator you can register devices, and open a device to see its keys and connection strings, its twin and the telemetry it's sent recently:

You can also update a twin's desired properties, send telemetry as the device, and Pause a device to see how your backend copes when it goes quiet.

What's Supported

The IoT Hub emulator supports:

Authentication is supported using a device's SAS token (signed with its own keys), the hub's shared access policies or - over HTTPS - a Microsoft Entra token, checked against IoT Hub's data-plane roles.

Devices can send telemetry over AMQP, MQTT or HTTPS - but MQTT is served on port 5883 rather than 8883, so MQTT clients need their port set. The Locally CLI also has its own commands for the hub's data plane, such as locally iothub device create and locally iothub device send, so you don't need the Azure CLI's IoT extension.

IoT Hub also works with Locally's other emulators, as you'd expect - for example:

• Telemetry lands in the hub's built-in endpoint, served by the Event Hubs Emulator - so a consumer reading messages/events works unchanged.
• DeviceCreated, DeviceDeleted, DeviceConnected, DeviceDisconnected and DeviceTelemetry events are sent to the hub's system topics in the Event Grid Emulator.

Differences from Azure

As of Locally v2026.09.02, the IoT Hub emulator has the following differences from Azure:

• Cloud-to-device messages can't be sent yet. Devices can listen for them over AMQP and MQTT, but there's no service-side send.
• Over AMQP, the .NET device SDK's twin and direct method links aren't recognised - use MQTT for twins and direct methods.
• Only symmetric key authentication is supported - X.509 certificates aren't.
• Message routing isn't supported, so telemetry always goes to the built-in endpoint.
• Jobs, file upload, module identities and the Device Provisioning Service aren't available.
• MQTT is version 3.1.1 only, and there's no MQTT or AMQP over WebSockets.
• Device queries support SELECT * FROM devices with equality filters only.
• Chaos Engineering isn't available for IoT Hub yet.

Should you encounter any issues, please take a look at the troubleshooting section.