Apache and Nginx are two most popular web servers in the Linux domain. Apache can be used on Windows server but IIS is the most popular choice there. It is needless to say that Linux servers are always preferred by the developers unless of course the web application is based on ASP.Net. When it comes to Linux web servers that are open-source in nature, the question boils down to whether one should go for Apache or Nginx. The web developer community has been shifting from Apache to Nginx apparently and there are various stats available that reveal Apache is losing market share considerably and Nginx is gaining it significantly. There is also a belief that Nginx is faster in performance than Apache. But the truth is that in the commercial project deployment, developers are using Nginx along with Apache to get the optimal performance that none of them can provide individually.

Reasons Why Developers Like To Use Both –

Unique Features – When there are two web servers competing against one another, it is logical to assume for anyone that they must have some differences and unique features that set one apart from the other. Indeed, there are differences like both of them are best for different types of workloads. To be specific, Nginx is a perfect choice when it comes to handling static content on your website. Apache is an ideal option when you have dynamic content on your website to handle swiftly when the web traffics are coming in massive numbers. If developers use both of them, they can handle static and dynamic contents in the best possible way.

Unexpected Traffic – It is not possible for a developer to predict the peaks and lows of web traffics for the particular web application he is developing. There could be a few occasions when the web traffic are extremely high in number and for the rest of the time, there could be very low web traffic. A developer has to make a robust application that can support high traffic scenarios effortlessly. It is safe to assume that all the developers start with Apache for their development as it is the most user-friendly technology of them all and its learning curve is thin and short.

Apache has multithread blocking model which is great for lightweight traffic. But as the traffic number goes up, the usage of memory goes up linearly and at some point, the website will crash due to a bottleneck scenario. On the other hand, Nginx has single thread non-blocking model which ensures that memory usage does not go up significantly to cause bottleneck scenario even when there is an unexpectedly high web traffic number.

Efficient Memory Management – From the above-mentioned point of handling the unexpectedly high traffic, it might seem appropriate to use only Nginx rather than using it with Apache. But in real life, Nginx fails to handle heavy web traffic alone if it has to deal with dynamic content. Dynamic contents are always changing and this is where PHP has to do most of the works rather than the web server doing everything. But in static contents, there is literally no work for PHP from calculation and execution point of view and hence, everything is dependent on the web servers.

By using Nginx, you can allocate a certain space of the memory for static content so that even when the traffic is high, the provided space is enough to serve everyone instantly. Then you can allocate the rest of the available space which is at least higher than the previous allocation to Apache for handling the dynamic content. If your website is having more static content, you can allocate more space to Nginx but enough space to Apache to handle the dynamic content smoothly even when the traffic is high. If the website has more dynamic content, you can allocate the least space to Nginx for static content and as much space as possible for the peak time. This concept is called reverse proxy.

Compatibility –Some developers are choosing Nginx over Apache especially when they are developing new web applications from scratch. They are using PHP-FPM along with Nginx for dynamic content. But if there are web applications that are built in Apache from the very beginning, not many developers will dare to shift completely to Nginx because of the compatibility issue. It is very easy for an existing application to shift the load of its static content to Nginx web server without affecting the overall design as static contents are files that the developers possess on their hard drive or local server. Dynamic parts are not in the hand of the developers as they are programming logic. Making a shift from the existing system to a completely different web server can give rise to several glitches and compatibility issues especially when the application was developed in Apache from the very beginning. This is another vital reason for developers to use both of them in combination.

Rather than using Apache or Nginx as the standalone web server for a web application that has an equal amount of static and dynamic content, it is always recommended to harness the best qualities of both the servers and deliver an optimal performance to the users.