Kubernetes has limited built-in network support called kubenet. It provides some basic network connectivity, but it’s much more common to use third-party Network implementations, which plug into Kubernetes using the CNI(Container Network Interface) API. Project Calico
Free and open source, Project Calico is designed to simplify, scale, and secure container and Kubernetes networks…www.tigera.io CNI config files are used to determine which CNI plugins to run. There’s different kinds of…