Every so often with Pressflow and Varnish you might find that your anonymous users aren't being cached via Varnish.

A quick way to see whether your anonymous pages are being served is to add some debugging headers to Varnish by adding some code like the snippet here to vcl_deliver()

<br> sub vcl_deliver {<br>   if (obj.hits &gt; 0) {<br>    set resp.http.X-Varnish-Cache = "HIT";<br>  }<br>  else {<br>    set resp.http.X-Varnish-Cache = "MISS";<br>  }<br> }<br>

and hit them with<br>  curl -I <a href="http://yoururl.com/" title="http://yoururl.com">http://yoururl.com</a><br>

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