On Thu, Dec 29, 2011 at 8:49 PM, Tim Starling tstarling@wikimedia.org wrote:
A VCL routine which parses this header and uses it to make caching decisions would solve your problem and, if published, would also be useful to other sites using Varnish with MediaWiki.
In case it's useful for hacking purposes: It also looks like Wikia's Varnish config is public and there's a presentation from Artur about it.
https://svn.wikia-code.com/utils/varnishhtcpd/ http://www.scribd.com/doc/48960012/Varnish-A-State-of-the-Art-High-Performan...
The VCL file doesn't evaluate X-Vary-Options but it simply unsets cookies for logged out users.