My site sits on a server that uses Varnish as a (powerful) caching engine.
Unfortunately, it seems wordpress is busting the Varnish cache by sending a cache-control http header. If I
curl -I domain.com I get:
HTTP/1.1 200 OK Server: Apache/2.4.10 X-Powered-By: PHP/5.4.4-14+deb7u14 Expires: Thu, 19 Nov 1981 08:52:00 GMT Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0 Pragma: no-cache Set-Cookie: PHPSESSID=e00738aoughg407ljm270kj0l6; path=/ Content-Type: text/html; charset=UTF-8 Accept-Ranges: bytes Date: Fri, 31 Oct 2014 21:44:16 GMT Connection: keep-alive Via: 1.1 varnish Age: 0
I have other wordpress sites hosted on this server, which work correctly with the Varnish server, so I'm pretty sure the problem is caused by this specific installation. Here is what I tried:
- disable all plugins. Empty Varnish cache, then
curl -I: same result.
- looked through all my theme files. Nothing suspicious.
Do you have any other idea as to what may cause the problem?