Connect to AWS MQTT

Question

Trying to connect to AWS IOT device from C# by using M2MQTT library :

public void connect()
        {

            const string IotEndpoint =  "a3cnel9bxxxxx-ats.iot.eu-central-1.amazonaws.com";
            const int BrokerPort = 8883;

            const string Topic = "topic_1";
            

            X509Certificate clientCert = X509Certificate2.CreateFromCertFile("C:\\cpp_test\\certs\\pi4\\certificate.pem.crt");
            X509Certificate caCert = X509Certificate.CreateFromCertFile("C:\\cpp_test\\certs\\Amazon-root-CA-1.pem");

            
            MqttClient client = new MqttClient(IotEndpoint, BrokerPort, true, caCert, clientCert, MqttSslProtocols.TLSv1_2);
            
            String message = "Test message";
            string clientId = Guid.NewGuid().ToString();

            
            
        try
        {
            client.Connect(clientId);
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
            if (ex.InnerException != null)

                MessageBox.Show("Inner exception: {0}", ex.InnerException.Message);

        }
            
            client.Publish(Topic, Encoding.UTF8.GetBytes(message));

        }

Got exception:

 Received an unexpected EOF or 0 bytes from the transport stream.

What might be wrong? Where is starting point of problem solving?

Answer 1

Getting no data is often a result of the SSL handshake failing or protocols not being supported, verify the certificates and protocols are correct.