OTA update with ESP failed, "connection refused" error appeared!

[nh5701]

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"How can I fix the "connection refused" error when using the OTA update feature with the esp kit?",

Platform

• Hardware: [ESP-12|ESP-01|ESP-07|ESP8285 device|ESP32]
• Development Env: [Platformio]
• Operating System: [Ubuntu]

Settings in IDE

• platform = espressif32
• board = esp32dev
• framework = arduino
• lib_extra_dirs = lib/libesp32
• monitor_speed = 115200
• board_build.f_cpu = 240000000L

Problem Description

I have an ota link loaded into String ota_get_urllink = ""; before. For example: https://getOTA update link. On my computer, I can still access that link to download the file, but when using ESP, the DNS domain name cannot be resolved. The "connection refused" phenomenon still occurs from time to time. Many times ESP still downloads files successfully and updates successfully. Please tell me how to handle this problem?
Thank!

MCVE Sketch

#include <Arduino.h>
#include <WiFiClientSecure.h>
String ota_get_urllink = "https://getOTA"; //example link
void update() {
WiFiClientSecure client;
  // WiFiClient client;
  Serial.println("UpdateOTA.....");
 // client.setCACert(rootCACertificate);
  client.setInsecure();
  client.setTimeout(240); //timeout 4 phut
  httpUpdate.setLedPin(LED_BUILTIN_IR, LOW);
  t_httpUpdate_return ret = httpUpdate.update(client, ota_get_urllink);
  switch (ret) {
  case HTTP_UPDATE_FAILED: //ret = 0
    Serial.printf("HTTP_UPDATE_FAILD Error (%d): %s\n", httpUpdate.getLastError(), httpUpdate.getLastErrorString().c_str());

    break;
  case HTTP_UPDATE_NO_UPDATES: //ret = 1
    Serial.println("HTTP_UPDATE_NO_UPDATES");
    break;

  case HTTP_UPDATE_OK: //ret = 2
    Serial.println("HTTP_UPDATE_OK");
    break;
  }
}

Debug Messages

HTTP_UPDATE_FAILD Error (-1): HTTP error: connection refused

HTTP_UPDATE_FAILD Error (-1): HTTP error: connection refused

[d-a-v]

There is an updater debug option.