title: Cannot create PoolableConnectionFactory
body: <p>What is the problem? Can't connect to database?    </p>
  
  <pre><code>   org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (
              Communications link failure 
      The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.)
  </code></pre>