Bug when reconnecting to MQTT

[ababere]

Library/API/IoT binding

nanoFramework.M2Mqtt

Visual Studio version

VS2026

.NET nanoFramework extension version

No response

Target name(s)

Freenove ESP32-S3

Firmware version

No response

Device capabilities

No response

Description

If, after connecting to the MQT broker, the network is interrupted or the MQTT broker stops working, the socket hangs and the program stops responding to requests.

In the nanoFramework.M2Mqtt MqttClient.cs library (line 1653), the connection is closed and an attempt is made to access the socket.

                    if ((_eventQueue.Count == 0) && _isConnectionClosing)
                    {
                        // client must close connection
                        Close();

                        // client raw disconnection
                        OnConnectionClosed();
                    }

However, at this point, in the MqttNetworkChannel.cs, line 152, the creation and connection are called.

            _socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

            // try connection to the broker
            _socket.Connect(new IPEndPoint(_remoteIpAddress, _remotePort));

and the program hangs. No exceptions are raised.

The goal is to endlessly attempt to connect to the MQTT broker.

How to reproduce

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Expected behaviour

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Screenshots

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Sample project or code

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Aditional information

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