title: Symfony 3, cache:clear error connection timeout
body: <p>On server i am trying clear cache but after run this command (<code>php bin/console cache:clear --env=prod</code>) a get error:</p>
  
  <blockquote>
    <p>[Doctrine\DBAL\Exception\ConnectionException]
      An exception occured in driver: SQLSTATE[HY000] [2002] Connection timed out</p>
    
    <p>[Doctrine\DBAL\Driver\PDOException]
      SQLSTATE[HY000] [2002] Connection timed out</p>
    
    <p>[PDOException]
      SQLSTATE[HY000] [2002] Connection timed out</p>
  </blockquote>
  
  <p>Database credentials are in <code>parameters.yaml</code> and connection to db is working... Whole web is working...</p>
  
  <p>Can anybody give me some hints/direction? Thx.</p>