With Apache and NGINX, users have two stable, secure open source projects available to them. But after the comparison, neither of the web servers is the clear winner. Both projects are based on fundamentally different design decisions that can be either an advantage or a disadvantage, depending on how the software is used.
The Apache HTTP server offers an immense repertoire of modules which, together with the flexible configuration options, open numerous fields of application for the software. The web server can also be a standard software for shared hosting scenarios and will continue to stand its ground in its field against lightweight web servers such as NGINX. The ability to directly integrate interpreters for programming languages such as PHP, Perl, Python, or Ruby into the web server using modules allows for dynamic web content to be delivered without the use of a separate application server. This makes the Apache HTTP server a comfortable solution for small and medium-sized websites where content is dynamically created during retrieval.
NGINX, on the other hand, doesn’t offer any possibilities to natively process dynamic web content or integrate corresponding interpreters via modules. A separate application server is always required. This may seem like unnecessary extra effort for small to medium-sized websites. However, such an architecture shows its strength for large web projects and increasing traffic volumes.
In general, NGINX is used as a load balancer in front of a group of application servers. The load balancer accepts incoming requests and decides, depending on the type of request, whether it needs to be forwarded to a specialized server in the background. Static web content is delivered directly by NGINX. If a client requests dynamic content, then the load balancer gives the request to a dedicated application server. This interprets the programming language, assembles the requested content into a webpage, and gives it back to the load balancer, which delivers it to the client. In this way, high traffic volumes can effectively be managed.
NGINX caches already deliver content for a certain amount of time, so that newly requested dynamic content can be delivered directly by the load balancer without NGINX having to access an application server again.
The outsourcing of interpreters to one or multiple separate backend servers has the advantage that the server network can easily be scaled if additional backend servers need to be added, or systems that are no longer necessary can be switched off. In practice, many users rely on a combination of NGINX and Apache for such a setup, and use the strengths of both servers.