Kubernetes is an open source cluster management system that was originally designed by Google. Looking at the popularity charts, it is a clear winner among other competitors such as Docker Swarm and Apache Mesos. Its popularity has grown so fast that most cloud platforms provide Kubernetes out of the box. It's not Docker-native, but there are a lot of additional tools and integrations to make it work smoothly with the whole Docker ecosystem; for example, kompose can translate Docker Compose files into Kubernetes configurations.
In the first edition of this book, I recommended Docker Compose and Docker Swarm for application dependency resolution and server clustering. While they're both good tools, Kubernetes' popularity grew so high recently that I decided to use Kubernetes as the recommended approach and keep Docker-native tooling as an alternative...
