Openshift MySQL Cartgridge上的连接超时

I'm deploying a PHP app which uses Doctrine as ORM in Openshift. In my post_deploy action hook I run doctrine orm schema-tool to update the DB but I'm getting a Connection Timeout error. As I'm farily new to Openshift, what is the best way to setup the database on Openshift?I'm deploying a PHP app which uses Doctrine as