What was the biggest change of 2017 in the world of containers? Without a doubt, it was Kubernetes’s rise to dominance.
At the start of 2017, Kubernetes was just an orchestrator. It was one of several open source tools available for managing clusters of Docker containers.
Fast forward to the present, however, and Kubernetes has taken the container ecosystem by storm. It has basically become the new Docker, in the sense that it is the name that now dominates most conversations about container technology.
How Kubernetes Took Over the Container World
To understand how the role of Kubernetes has evolved over the past year, you have to step back a bit and think about what Kubernetes has come to stand for.
In a technical sense, Kubernetes is still just an orchestrator. Apart from gaining a few new features, Kubernetes hasn’t actually changed in a substantive way over the course of 2017. Kubernetes remains just one of several tools that you need to build a functional container environment.
Yet in a broader sense, Kubernetes has become a shorthand for an entire software environment based on Kubernetes. Just as people use Linux as a shorthand for complex operating systems of which Linux is merely one component, they are now saying Kubernetes to refer to container environments that are built using a number of different tools.
What makes this trend notable is not simply that the word Kubernetes is being used to mean more than just Kubernetes the orchestrator.
What’s really interesting is that, for many people, Kubernetes has now become the go-to term for talking about any kind of container-based environment.
This is because Kubernetes has gradually edged out Docker Swarm, Mesos and other orchestrators. Now, when people think of containers, they automatically think of Kubernetes, because Kubernetes has gained so much adoption.
Explaining the Rise of Kubernetes
The reasons why this has happened are up for debate. I’m not convinced that Kubernetes is hands-down better in a technical sense than Swarm or Mesos.
I tend to think the shift has more to do with ecosystem-level changes. Perceptions of Docker as a somewhat selfish company that is invested more in its own business model than in promoting open source container technology have limited the adoption of Docker Swarm. (Whether those perceptions are fair is a separate issue.)
These moves have shifted the winds within the container ecosystem in Kubernetes’ favor. Kubernetes’ technical features have become more or less immaterial; what matters now is that when people think of containers, they think of Kubernetes.
That’s a huge change from early 2017. Will Docker recover its mindshare in 2018? I’m skeptical.