title: How to ping the address for postgres?
body: <p>I am trying to set up postgres with docker. I want to verify the address for my database, thus I tried <code>ping 0.0.0.0:5432</code> and <code>ping 127.0.0.1:5432</code> and <code>ping localhost:5432</code>, but all returned <code> Unknown host</code> and cannot be resolved.</p>
  <p>Why is that? what is the correct address for postgres? My psql is running correctly.</p>