NodeMcu connection to MQTT

[istratesorin]

Hello! So i have a problem with my NodeMcu board. I have setup a mosquitto mqtt broker on my PC (it is connected through a ethernet cable if that matters), that has the local ip 192.168.1.4. I use a conf file that has listener 1883 and allow_anonymous true so i allow all connections. I also have a OneWire DS18B20 sensor, but that is not an issue, it works fine. I have setup my NodeMcu to connect to Wi-Fi (on the same network), and using the PubSubClient library i try to connect to my broker to send the data from the one-wire sensor to it. Here is my code

#include <ESP8266WiFi.h>
#include <PubSubClient.h>
#include <OneWire.h>
#include <DallasTemperature.h>

// Wi-Fi credentials
const char* ssid = "my_ssid";
const char* password = "my_password";

// MQTT broker details
const char* mqtt_server = "192.168.1.4";
const int mqtt_port = 1883;

// OneWire bus
const int oneWireBus = 4;

OneWire oneWire(oneWireBus);
DallasTemperature sensors(&oneWire);

WiFiClient espClient;
PubSubClient client(espClient);

void setup_wifi() {
  delay(10);
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);

  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }

  Serial.println("");
  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
}

void reconnect() {
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    if (client.connect("ESP8266Client")) {
      Serial.println("connected");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

void setup() {
  Serial.begin(115200);
  setup_wifi();
  client.setServer(mqtt_server, mqtt_port);
  sensors.begin();
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }
  client.loop();

  sensors.requestTemperatures();
  float temperatureC = sensors.getTempCByIndex(0);

  Serial.print("Temperature: ");
  Serial.println(temperatureC);

  char tempStr[8];
  dtostrf(temperatureC, 1, 2, tempStr);
  client.publish("home/temperature", tempStr);

  delay(5000); // Delay between readings
}

But when i run it it always gives me "Attempting MQTT connection...failed, rc=-2 try again in 5 seconds". It connects to Wi-Fi, gives me the ip (192.168.1.3) but still it fails to connect to the broker. I have setup a port forward in my router config to send it all from 1883 to my PC. I am really stuck here, any help would be very much appreciated!

Thanks in advance!

[UKHeliBob]

Welcome to the forum

const char* mqtt_server = "192.168.1.4";

This is the wrong syntax when connecting to an IP address by IP address

Try

IPAddress mqtt_server(192, 168, 1,4);