Kubernetes vs. Docker

A battle for supremacy in the container business? Kubernetes vs. Docker? Well, yes and no. Docker created a little revolution with the development of container technology. Virtualization with self-contained packages (or containers) opens up all kinds of new possibilities for work in software development. On the other hand, Kubernetes has found a niche that emerged with this new way of working: Anyone who works with lots of containers has to be able to manage them efficiently. Kubernetes enables precisely that – but is always based on Docker or other container services.

At the same time, however, Docker offers its own orchestration tool: Docker Swarm. It provides users with similar features to Kubernetes. Strictly, it’s a matter of Docker Swarm vs. Kubernetes.

Kubernetes is an application for orchestrating (i.e. managing) containers. But the program doesn’t create the containers itself. Here, Kubernetes depends on a container platform. Docker is by far the most popular solution in this area – but there are also alternatives to Docker. Kubernetes uses existing container tools and involves them in its own workflow. This allows you to easily integrate containers created with Docker or another tool into Kubernetes. You can then use orchestration to manage, scale, and move the containers.

Kubernetes ensures that everything runs as it should and also provides a replacement if a node fails. So, combining Kubernetes and Docker enables you to benefit from a highly robust container environment.

Although Kubernetes also works with other container platforms, Docker is the most popular option for good reason – not only since Docker popularized container visualization, but also because Kubernetes and Docker serve similar purposes. Both are also backed by a strong open-source community. In fact, using them both together works so well that Docker can even be obtained in a package with Kubernetes, even though Docker offers its own orchestration tool.

Even though Kubernetes and Docker harmonize really well, competition does exist when it comes to Swarm. Although Docker is compatible with both solutions and can even switch between the two, Docker Swarm and Kubernetes can’t be combined. Users therefore face the question of whether they wish to use the highly popular Kubernetes system or Swarm, which belongs to Docker.

Generally, the setup of both tools is very similar; only the names of the individual aspects differ. The application purpose is also identical: effectively managing containers and ensuring the most efficient use of resources via intelligent scaling.

Swarm reveals some of its advantages during the installation: Since the tool is an integral component of Docker, the transition is really easy. While it’s necessary to first set up orchestration with Kubernetes (which admittedly is not particularly difficult), everything is already in place with Swarm. However, as many users already likely work with Docker, they don’t need to familiarize themselves with how a new program works.

By contrast, Kubernetes offers its own intuitive GUI: The application’s dashboard not only provides an excellent overview of all aspects of the project, it can also perform a number of different tasks. On the other hand, Swarm only offers this convenience with the use of additional programs.

Kubernetes also excels in terms of functionality: While Swarm needs extra tools for monitoring and maintaining a log, these tasks are already included as standard in the Kubernetes toolset.

However, the main benefits of both programs can be found in scaling and ensuring availability. In this case, Docker Swarm is generally better with respect to scalability. The reason for this is the complexity of Kubernetes, which makes it sluggish to some degree. Nonetheless, the complex system ensures that automatic scaling is better with Kubernetes. What’s more, a major advantage of Kubernetes is that it monitors the condition of containers at all times and immediately compensates for failures.

Swarm performs better with its load balancing: even distribution of load is a matter of course with Swarm. In the case of Kubernetes, a little workaround is necessary for load balancing. Here, deployments first need to be changed into services in order to benefit from load balancing.

To help you decide which solution is best for you, we’ve contrasted Docker Swarm and Kubernetes in terms of various user-relevant aspects: