Overview of essential Kubernetes networking fundamentals including IP addressing, routing, DNS, network namespaces, CNI, pod networking, service networking, load balancing, and ingress with hands on examples
This lesson introduces the core networking concepts you need for Kubernetes. It focuses on practical fundamentals and cluster-specific networking patterns so you can follow later lessons and real-world examples with confidence.We cover these essential networking basics up front:
Setting and verifying IP addresses on a Linux host
Gateways, routes, and how routing affects cluster traffic
Name resolution and DNS configuration on Linux
How network namespaces are used by container runtimes
These basics make the Kubernetes networking material easier to grasp and provide immediate, practical skills you can apply while following demos and labs.
Recommended prerequisites: familiarity with network namespaces and Docker (or another container runtime). These make Kubernetes networking topics much easier to understand and follow.
If you’re new to any of these topics, the short prerequisite materials linked above will give you the background needed to proceed. They are intentionally brief and optional — review what you need.
The course is arranged to progressively build a working mental model of Kubernetes networking. Each lesson depends on the preceding concepts:
Lesson
Focus
Key takeaways
Cluster networking requirements & constraints
How nodes and pods communicate across the cluster
IP addressing model, routing considerations, policy constraints
Pod networking concepts
Pod IPs, pod-to-pod communication, network namespaces
Pod IP lifecycle, localhost vs. pod network
Container Network Interface (CNI)
How Kubernetes uses CNI to implement Pod networking
CNI plugin types, how CNI configures interfaces and routes
Cluster DNS
How Kubernetes implements DNS for services and pods
CoreDNS, DNS records for Services and Pods
Service networking, Load Balancers, Ingress, Gateway API
Service discovery, load balancing patterns, north-south traffic
ClusterIP, NodePort, External LoadBalancers, Ingress, Gateway API concepts
We conclude the section with Ingress and related topics (Service networking, Load Balancers, and Gateway API). These lessons are hands-on and include real-world configuration examples and demonstrations to reinforce the concepts and show how they apply to production clusters.Further reading and references:
