title: serf failing, sending https request to port 80 instead of 443, why?
body: <p>When requesting via https it looks like serf is funnelling the request via port 80 instead of 443?</p>
  
  <pre><code>[Mon Jan 16 10:25:48.007386 2017] [error] [pid 350] [mod_pagespeed 1.11.33.4-0 @350] Serf status 120171(APR does not understand this error code) polling for 1 threaded fetches for 0.05 seconds
  [Mon Jan 16 10:25:48.007539 2017] [error] [pid 350] [mod_pagespeed 1.11.33.4-0 @350] Serf status 120171(APR does not understand this error code) polling for 1 threaded fetches for 0.05 seconds
  [Mon Jan 16 10:25:53.021234 2017] [warn] [pid 350] [mod_pagespeed 1.11.33.4-0 @350] Fetch timed out: https://www.domain.com/assets/76dc6ad2/style.min.css (connecting to:10.33.12.222:80) (1) waiting for 50 ms
  </code></pre>
  
  <p>SSL termination on the load balancer. SSL is also configured to work from behind the load balancer as well so https can be served from within the network.</p>
  
  <pre><code>ModPagespeedFetchHttps enable
  ModPagespeedRespectXForwardedProto on
  ModPagespeedEnableFilters prioritize_critical_css
  </code></pre>
  
  <p>How to have serf request https via port 443?</p>