Connection problem to MQTT broker

Hi
my arduino client can't connect to the public broker test.mosquitto.com.

The Serial Monitor output: Connecting to MQTT... failed state : -2

Here is the code, where is the problem?I don't find it :

#include <PubSubClient.h>
#include <Ethernet.h>
#include <SPI.h>

byte mac[] = {0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0x01};

const char* mqttServer = "test.mosquitto.com";
const int mqttPort = 1883;
//const char* mqttUser = "YourMQTTUsername";
//const char* mqttPassword = "YourMQTTPassword";
EthernetClient ethClient;
PubSubClient mqttClient(ethClient);

void setup_Ethernet(){
// start the Ethernet connection:
Serial.println("Initialize Ethernet with DHCP:");
if (Ethernet.begin(mac) == 0) {
Serial.println("Failed to configure Ethernet using DHCP");
if (Ethernet.hardwareStatus() == EthernetNoHardware) {
Serial.println("Ethernet shield was not found. Sorry, can't run without hardware. :(");
} else if (Ethernet.linkStatus() == LinkOFF) {
Serial.println("Ethernet cable is not connected.");
}
//delay to let Etnernet shield initialize
delay(1000);
}
//connection succesful
Serial.println("Connection Successful");
Serial.println("--------------------");

}

void callback(char* topic, byte* payload, unsigned int length)
{
Serial.print("Messageved in topic: ");
Serial.println(topic);
Serial.print("Message :");
for(int i = 0; i < length; i++) {
Serial.print((char)payload*);*

  • }*
  • Serial.println();*
    }
    void setup() {
  • Serial.begin(9600);*
  • setup_Ethernet();*
  • mqttClient.setServer(mqttServer,mqttPort);*
  • mqttClient.setCallback(callback);*
  • while(!mqttClient.connected()) {*
  • Serial.println("Connecting to MQTT...");*
  • if (mqttClient.connect("arduinoClient")) {*
  • Serial.println("connected");*
  • }else{*
  • Serial.print("failed state : ");*
  • Serial.println(mqttClient.state());*
  • delay(2000);*
  • }*
  • }*
  • mqttClient.publish("test/arduino","Hello Arduino world");*
  • mqttClient.subscribe("test/arduino");*
    }
    void loop()
    {
  • mqttClient.loop();*
    }

try with this broker
const char* mqtt_server ="broker.mqttdashboard.com"; and delette MQttuser and MQTTpassword
client.connect("ESP8266Client") it work