How to troubleshoot messages sent from local compter to Azure IOT Hub using WireShark?

Question

I am sending messages from my C# application to IOT Hub using below code snippet.

    public async Task<MessageToTargetStatus> ForwardMessage(byte[] message)
    {
        var messageToSend = new Microsoft.Azure.Devices.Client.Message(message);            
        await iotHubClient.GetDeviceClient().SendEventAsync(messageToSend).ConfigureAwait(false);
        return MessageToTargetStatus.Success;
    }

Messages are successfully received at the Azure IOT Hub

Now I want to test my security of these messages and trying to verify these messages in WireShark.

I see many records in WireShark , but I am not able to figure out which is my messages sent to IOT Hub.

How can I do it? I am using MQTT at port 1833, running as `Windows Service'.

I have added filter as follow, but no luck

MQTT I might need to force the packets over a networkadapter, using localhost windows will use loopback instead of the network interface card. So how can I do it in WireShark?

Updated question with Device Explorer tool screenshot

When I send single message from Device Explorer , I see many communication records in WireShark . Which protocol I should be filtering?

Connection string - I am using Mqtt_WebSocket_Only

  _hubClient = DeviceClient.CreateFromConnectionString(IotHubConnectionString, TransportType.Mqtt_WebSocket_Only);

Answer 1

Azure IoT Hub only supported security communication, for MQTT protocol it use 8883 port number. So you need change capture filter to tcp.port == 8883 .

Ref: Azure IoT Hub communication protocol and ports

Or find the Azure IoT Hub IP address using the following command:

ping [your-hub-name].azure-devices.net

Then use this filter:

ip.addr == [iothub-address]

If you use AMQP, its port is 5671. You can set filter in Wireshark like this: