title: Varnish cache - how long the pages are cached?
body: <p>I have a doubt regarding the working of vanish cache.
  I installed the varnish cache with my apache web sever and configured the same correctly, so that I can access web pages through varnish cache. </p>
  
  <p>The question is here, that I have created a 'test.php' page and this can be accessed through browser. I have changed the content of the page and immediately after again accessed the same page through browser. The second time it was showing the changed content. Why it is so? Up to my knowledge, the second time also it should show the old content (?); because varnish cache will retain contents of web pages for a shot interval.
  Is there any settings that I need to change? Please advice.</p>
  
  <p>Thank You.</p>