It has been verified that when using the "index_page" setting, the home page is not delivered with Vary on X-User-Hash but with Vary on cookie. This means for each user a different home page will be generated and cached, which is highly inefficient. Vary on X-User-Hash would be correct (which means: cache the page for each user having the same roles).
1. Prepare a new eZ Publish 5.4 installation, fully updated to the latest version, 5.4.5;
2. Use the following configuration on ezpublish.yml:
3. Edit vhost file, and make sure http_cahing is enabled i.e. is using the default "SetEnv USE_HTTP_CACHE 1";
4. Call the page (http://54ezdemo.com/eng) and check http-headers (for the first time loading):
Notice the "Vary" header is "Vary:Cookie,Accept-Encoding,Authorization,X-User-Hash". When "index_page" is not used, the vary header is "Vary:X-User-Hash,Accept-Encoding", which is correct.