title: Getting `Cannot mix POST with other methods` error when using `ab -p`
body: <p>I'm using ApacheBench (<code>ab</code>) to stress test my site. When I specify a method <code>-m POST</code> and some postdata <code>-p {datafile}</code>, I get the message</p>
  
  <blockquote>
    <p>Cannot mix POST with other methods.</p>
  </blockquote>
  
  <p>The trouble is that I'm not actually mixing POST with other methods. Here's my full command:</p>
  
  <pre><code>ab -m POST -p postdata.txt -n 1000 -c 100 http://example.com/
  </code></pre>