title: SMTP : Simple Unix command
body: <p>What is the command to test a smtp host that whether reachable from my unix machine through port 25 using valid authentication details? </p>
  
  <p>Lets say: </p>
  
  <pre><code>host: smtp.gmail.com 
  port: 25
  username: someusername
  password: somepassword
  </code></pre>
  
  <p>how to test this is reachable from my machine?</p>
  
  <p>Thanks :)</p>