title: Running different versions of postgresql side by side
body: <p>I have postgresql 9.3 installed.
  I would like to have also postgres 9.6.1 installed.</p>
  
  <p>Each application is using a different DB. Most of the times I don't run both applications, so I don't need them to run concurrently.</p>
  
  <p>I downloaded the installer recommended by <a href="http://www.enterprisedb.com/products/pgdownload.do#linux" rel="nofollow noreferrer">postgres</a>, and installed 9.6.1, but then it seems that 9.3 is not able to start anymore. I'm getting an error trying to run <code>sudo service postgres start</code>:</p>
  
  <blockquote>
    <ul>
    <li>Starting PostgreSQL 9.3 database server </li>
    <li>The PostgreSQL server failed to start. Please check the log output.</li>
    </ul>
  </blockquote>
  
  <p>The log file is empty (not sure that's the interesting one) - /var/log/postgresql/postgresql-9.3-main.log</p>
  
  <p>Any idea how to be able to run both instances?</p>