Nginx is a supplementary high-performance web server specifically designed for delivering large amounts of static content.
This means that a server running Plesk will run two web servers:
– Nginx on ports 80 and 443.
– Apache on ports 7080 and 7081.
The server is configured to work as a reverse proxy - nginx as a front end web server that processes all incoming requests from site visitors. These requests are sent to Apache which, in turn, distinguishes requests for static and dynamic content.
If the request is for a static file (like jpg, css, html) Apache passes the request through all registered handlers and returns to nginx a response which contains only a location of the requested file on the file system. If the request is for a dynamic file (like a PHP script), Apache executes the file and sends the response to nginx, which delivers it to the client.
Such combination of two servers gives the following advantages:
> The maximum number of concurrent connections to a website increases.
> The consumption of server CPU and memory resources decreases.
> Efficiency of serving visitors with slow connection speed (GPRS, EDGE, 3G, and so on) improves.
Installing nginx for Plesk 11 & plesk 12.
If Plesk is directly installed, nginx will be turned on by default.
If it is upgrade from earlier versions, we can add the nginx component at any time after the upgrade in Tools & Settings > Updates & Upgrades > Add Components.
Once the component is added, we should run the Reverse Proxy Server (nginx) service in Tools & Settings > Services Management.
We can view the version of the installed nginx server in Tools & Settings > Server Components.
To return back to the configuration with a single Apache web server, stop the Reverse Proxy Server (nginx) service in Tools & Settings > Services Management.