This post is going to attempt to demystify the several layers of networking operating in a kubernetes cluster. Kubernetes is a powerful platform embodying many intelligent design choices, but discussing the way things interact can get confusing: pod networks, service networks, cluster IPs, container ports, host ports, node ports… I’ve seen a few eyes glaze over. We mostly talk about these things at work, cutting across all layers at once because something is broken and someone wants it fixed. If you take it a piece at a time and get clear on how each layer works it all makes sense in a rather elegant way.