How to implement the redis master-slave database status detection function using PHP?

<?php
/**
 * 检测多个主从redis数据库是否挂掉
 * 建立从数据库$redis_db的二维数组，内容包含每个从服务器的配置数据
 */
header("Content-Type: text/html; charset=utf-8");
set_time_limit(0);
$redis_db = array(
  &#39;db1&#39;=>array(
    &#39;hostname&#39; => &#39;127.0.0.1&#39;,
    &#39;port&#39; => 6379,
    &#39;password&#39; => &#39;&#39;,
  ),
  &#39;db2&#39;=>array(
    &#39;hostname&#39; => &#39;192.168.2.179&#39;,
    &#39;port&#39; => 6379,
    &#39;password&#39; => &#39;111111&#39;,
  ),
);
$content = &#39;&#39;;
foreach ($redis_db as $db_key) {
  $host = $db_key[&#39;hostname&#39;];
  $port = $db_key[&#39;port&#39;];
  $redis = new Redis();
  //连接本地的 Redis 服务
  $status= $redis->connect($host, $port);
  if(!$status) {
    $content .= "redis从数据库( $host )无法连接 ！ <br/>";
    continue;
  }
  if(!empty($db_key[&#39;password&#39;])) {
    $pass = $redis->auth($db_key[&#39;password&#39;]);
    if(!$pass) {
      $content .= "redis从数据库( $host )密码错误 ！ <br/>";
      continue;
    }
  }
  try {
    $config = $redis->info();
    if(&#39;up&#39; == $config[&#39;master_link_status&#39;]) {
    } else {
      $content .= "redis从数据库( $host )挂掉了！ <br/>";
    }
  }
  catch(RedisException $e)
  {
    $content .= "redis从数据库( $host )报错：" . $e->getMessage()."<br/>";
  }
}
//若报错信息不为空，发送报错邮件
if(!empty($content)) {
  $title = &#39;主从redis数据库状态检测报错 &#39;;
  $content = date("Y-m-d H:i:s",time()) . "<br/>" . $content;
  $sendurl = "http://localhost/api.com/test.php?title=".$title."&content=".$content;
  $result = file_get_contents($sendurl);
  if(&#39;ok&#39; != $result) {
    $message = date("Y-m-d H:i:s",time()).&#39; redisSlave.php 主从redis数据库状态检测报错 邮件发送失败!&#39;."\n";
    $content = str_replace("<br/>", "\n", $content);
    $message .= $content;
    error_log($message,3,"error.log");
  }
}