How a combination of Apache and nginx in proxy mode works in Plesk for Linux?
When website URL is opened in browser what happens is as follows:
- Nginx checks if it has the resource already in its cache.
- If the resource is cached, Nginx returns the cached content.
- If the resource is not cached or if dynamic page (e.g. index.php) is requested , Nginx proxies (forwards) the request to back end server - Apache. Apache in Plesk works on TCP ports: 7080 - http, 7081 - https. Then Nginx caches static content - html, images, js, css.