title: caching a value using memcache in yii2
body: <p>I followed the documentation and configured my config/main.php as they stated. </p>
  
  <p>now i try to access the memcache object as the following </p>
  
  <pre><code>Yii::$app-&gt;cache-&gt;Memcache-&gt;add('12', '12');
  </code></pre>
  
  <p>and get the value as the following </p>
  
  <pre><code>Yii::$app-&gt;cache-&gt;Memcache-&gt;get('12')
  </code></pre>
  
  <p>i don't get anything in the network section in chrome's inspect element feature for a few seconds and then i get this error:</p>
  
  <p>"MemcachePool::add(): php_network_getaddresses: getaddrinfo failed: Name or service not known&#039;"</p>