Access control restrictions are essential to day-to-day operation. Nginx includes a group of modules that let you allow or deny access depending on various conditions. Nginx denies access to a resource by returning a 403 (Forbidden HTTP) status or 401 (Unauthorized) if accessing the resource requires authentication. This 403 (Forbidden) status code can be intercepted and customized using the error_page directive.
Nginx allows you to permit or deny access to a virtual host or a location by IP address. For that, you can use the directives allow and deny. They have the following format:
allow <IP address> | <IP address>/<prefix size> | all; deny <IP address> | <IP address>/<prefix size> | all;
Specifying an IP address allows or denies access to a single IP address within a location, while specifying an IP address with a prefix size (for example 192.168.0.0/24 or 200.1:980::/32) allows or denies access to a range...