Remove X-Powered-By header in Nginx server

It is often desired to remove the 'X-Powered-By' from the HTTP headers. When using Nginx, it can be using a simple setting. The setting has to be in http section and it takes the following form.

<module_name>_hide_header X-Powered-By;

For example, if it is a FastCGI server the configuration setting will be as follows:

fastcgi_hide_header X-Powered-By;

If you are using Nginx as a load balancer, the configuration setting will be as follows:

proxy_hide_header X-Powered-By;

Unfortunately this configuration setting is not available yet in Passenger because Passenger is a thord party module and they have not implemented it yet.