title: Original sub-domain of rails app to Heroku
body: <p>I would like to set up original domain to Heroku. But I got stuck. Could you help me?</p>
  
  <p>What I did is as follows;</p>
  
  <p>①heroku domains:add www.example.com</p>
  
  <p>②DNS setting</p>
  
  <pre><code>a www 75.101.163.44
  a www 75.101.145.87
  a www 174.129.212.2
  </code></pre>
  
  <p>③host www.example.com</p>
  
  <p>and then I got this.</p>
  
  <p>Host www.example.com not found: 3(NXDOMAIN)</p>