title: Varnish Via and X-Varnish headers: are they needed in production?
body: <p>We have just deployed several varnish instances in production and I'm wondering whether is it ok to unset the <code>Via:</code> and <code>X-Varnish:</code> headers.</p>
  
  <p>As far as I read Via is only an info header, while X-Varnish is for debugging, but I didn't find info about whether they're optional or necessary.</p>
  
  <p>So is it safe to removed them like this?</p>
  
  <pre><code>sub vcl_deliver {
    unset resp.http.Via;
    unset resp.http.X-Varnish;
  }
  </code></pre>