Failed to connect to Hivemq and arduino state=2-CodePudding

everybody. I am trying to connect my ESP8266 board on my server in HiveMQ. Knowing that the in update would be a TLS-based connection, I had to adapt my code. However, so far I have not been able to stabilize the connection. Although I can upload the code to esp, it sends me the message: Attempting MQTT connection...failed, rc=-2 try again in 5 seconds. (Note: The hivemq Guide is wrong, many problems) I have installed OPENssl to get the certificates, but none of the three appeared to work. I'm waiting for help, please.

#include <ESP8266WiFi.h>
#include <PubSubClient.h>
#include <WiFiClientSecure.h>

//---- WiFi settings
const char* ssid ="myssid";
const char* password = "mypass";
//---- MQTT Broker settings
const char* mqtt_server =  "06f141f33c074deab7c362e9cf1f3eee.s1.eu.hivemq.cloud";
// This is my broker
const char* mqtt_username = "myuser";
const char* mqtt_password = "mypass";
const int mqtt_port =8883;

WiFiClientSecure espClient;
PubSubClient client(espClient);
unsigned long lastMsg = 0;

#define MSG_BUFFER_SIZE (50)
char msg[MSG_BUFFER_SIZE];

const char* sensor1_topic= "temperatura";
const char* sensor2_topic="umidade";

const char *x509CA PROGMEM = R"EOF("
-----BEGIN CERTIFICATE-----
MIIFFjCCAv6gAwIBAgIRAJErCErPDBinU/bWLiWnX1owDQYJKoZIhvcNAQELBQAw
TzELMAkGA1UEBhMCVVMxKTAnBgNVBAoTIEludGVybmV0IFNlY3VyaXR5IFJlc2Vh
cmNoIEdyb3VwMRUwEwYDVQQDEwxJU1JHIFJvb3QgWDEwHhcNMjAwOTA0MDAwMDAw
WhcNMjUwOTE1MTYwMDAwWjAyMQswCQYDVQQGEwJVUzEWMBQGA1UEChMNTGV0J3Mg
RW5jcnlwdDELMAkGA1UEAxMCUjMwggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEK
AoIBAQC7AhUozPaglNMPEuyNVZLD ILxmaZ6QoinXSaqtSu5xUyxr45r XXIo9cP
R5QUVTVXjJ6oojkZ9YI8QqlObvU7wy7bjcCwXPNZOOftz2nwWgsbvsCUJCWH jdx
sxPnHKzhm /b5DtFUkWWqcFTzjTIUu61ru2P3mBw4qVUq7ZtDpelQDRrK9O8Zutm
NHz6a4uPVymZ DAXXbpyb/uBxa3Shlg9F8fnCbvxK/eG3MHacV3URuPMrSXBiLxg
Z3Vms/EY96Jc5lP/Ooi2R6X/ExjqmAl3P51T c8B5fWmcBcUr2Ok/5mzk53cU6cG
/kiFHaFpriV1uxPMUgP17VGhi9sVAgMBAAGjggEIMIIBBDAOBgNVHQ8BAf8EBAMC
AYYwHQYDVR0lBBYwFAYIKwYBBQUHAwIGCCsGAQUFBwMBMBIGA1UdEwEB/wQIMAYB
Af8CAQAwHQYDVR0OBBYEFBQusxe3WFbLrlAJQOYfr52LFMLGMB8GA1UdIwQYMBaA
FHm0WeZ7tuXkAXOACIjIGlj26ZtuMDIGCCsGAQUFBwEBBCYwJDAiBggrBgEFBQcw
AoYWaHR0cDovL3gxLmkubGVuY3Iub3JnLzAnBgNVHR8EIDAeMBygGqAYhhZodHRw
Oi8veDEuYy5sZW5jci5vcmcvMCIGA1UdIAQbMBkwCAYGZ4EMAQIBMA0GCysGAQQB
gt8TAQEBMA0GCSqGSIb3DQEBCwUAA4ICAQCFyk5HPqP3hUSFvNVneLKYY611TR6W
PTNlclQtgaDqw 34IL9fzLdwALduO/ZelN7kIJ m74uyA eitRY8kc607TkC53wl
ikfmZW4/RvTZ8M6UK 5UzhK8jCdLuMGYL6KvzXGRSgi3yLgjewQtCPkIVz6D2QQz
CkcheAmCJ8MqyJu5zlzyZMjAvnnAT45tRAxekrsu94sQ4egdRCnbWSDtY7kh BIm
lJNXoB1lBMEKIq4QDUOXoRgffuDghje1WrG9ML Hbisq/yFOGwXD9RiX8F6sw6W4
avAuvDszue5L3sz85K EC4Y/wFVDNvZo4TYXao6Z0f lQKc0t8DQYzk1OXVu8rp2
yJMC6alLbBfODALZvYH7n7do1AZls4I9d1P4jnkDrQoxB3UqQ9hVl3LEKQ73xF1O
yK5GhDDX8oVfGKF5u decIsH4YaTw7mP3GFxJSqv3 0lUFJoi5Lc5da149p90Ids
hCExroL1 7mryIkXPeFM5TgO9r0rvZaBFOvV2z0gp35Z0 L4WPlbuEjN/lxPFin 
HlUjr8gRsI3qfJOQFy/9rKIJR0Y/8Omwt/8oTWgy1mdeHmmjk7j1nYsvC9JSQ6Zv
MldlTTKB3zhThV1 XWYp6rjd5JW1zbVWEkLNxE7GJThEUG3szgBVGP7pSWTUTsqX
nLRbwHOoq7hHwg==
-----END CERTIFICATE-----
")EOF";

void setup() {

Serial.begin(9600);
Serial.print("\nConnecting to ");
Serial.println(ssid);

WiFi.mode(WIFI_STA);
WiFi.begin(ssid, password);

while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
randomSeed(micros());
Serial.println("\nWiFi connected\nIP address: ");
Serial.println(WiFi.localIP());

while (!Serial) delay(1);


espClient.setCACert((const uint8_t*)x509CA, sizeof(x509CA) - 1);
client.setServer(mqtt_server, mqtt_port);
client.setCallback(callback);
}

void loop() {

  if (!client.connected()) reconnect();
  client.loop();

publishMessage(sensor1_topic,String("XXXX"),true);    
publishMessage(sensor2_topic,String("XXXX"),true);
}

//=======================================================================Function=================================================================================

void reconnect() {
// Loop until we’re reconnected
while (!client.connected()) {
Serial.print("Attempting MQTT connection…");
String clientId = "ESP8266Client"; // Create a random client ID
clientId  = String(random(0xffff), HEX);
// Attempt to connect
if (client.connect(clientId.c_str(), mqtt_username, mqtt_password)) {
Serial.println("connected");

  client.subscribe(sensor1_topic);   // subscribe the topics here
  //client.subscribe(command2_topic);   // subscribe the topics here
} else {
  Serial.print("failed, rc=");
  Serial.print(client.state());
  Serial.println(" try again in 5 seconds");   // Wait 5 seconds before retrying
  delay(5000);
}
}
}

//=======================================
// This void is called every time we have a message from the broker

void callback(char* topic, byte* payload, unsigned int length) {
String incommingMessage = "HELLO";
for (int i = 0; i < length; i  ) incommingMessage =(char)payload[i];
Serial.println("Message arrived");
// check for other commands
/* else if( strcmp(topic,command2_topic) == 0){
if (incommingMessage.equals(“1”)) { } // do something else
}
*/
}

//======================================= publising as string
void publishMessage(const char* topic, String payload , boolean retained){
if (client.publish(topic, payload.c_str(), true))
Serial.println("Published");
}

CodePudding user response：

After talking with another colleague, he came to a conclusion that perhaps an ESP8266 does not support TLS connections due to its low memory capacity, and that a better resolution is to bypass an encryption by adding the following code: replace: espClient.setCACert((const uint8_t*)x509CA, sizeof(x509CA) - 1); for: espClient.setInsecure();