Networking is a vast topic. There are many ways to set up networks and connect devices, pods, and containers. Kubernetes can't be opinionated about it. The high-level networking model of a flat address space for Pods is all that Kubernetes prescribes. Within that space, many valid solutions are possible, with various capabilities and policies for different environments. In this section, we'll examine some of the available solutions and understand how they map to the Kubernetes networking model.
The most basic environment is a raw bare metal cluster with just an L2 physical network. You can connect your containers to the physical network with a Linux bridge device. The procedure is quite involved and requires familiarity with low-level Linux network commands such as brctl, ip addr, ip route, ip link, nsenter, and so on. If you plan to implement it, this guide can serve as a good start (search for the With Linux Bridge devices section...