Technology · Ebook

Container Network Interface: Networking for Containers

by Shriira Press

The Container Network Interface (CNI) is the standard that decouples container platforms from container networking — defining how a runtime invokes a plugin to give each container its network. This free book teaches it from the ground up: what CNI is and the problem it solves, container networking fundamentals (namespaces, veth pairs, bridges, overlays, routing), the CNI specification (the ADD/DEL contract, the exec model, JSON config, plugin chaining), CNI plugins (reference plugins and full networking solutions), IP address management (IPAM), how Kubernetes uses CNI for pod networking (the flat-network model), the major plugins (Flannel, Calico, Cilium, Weave, cloud CNIs) and how they compare, network policy (securing pod traffic, enforced by capable CNIs), performance and dataplanes (overlay vs routing, iptables vs eBPF), and choosing and operating a CNI plugin in practice. Ten focused chapters with clear diagrams that demystify how every container — and every Kubernetes pod — gets its place on the network.

Contents

1. 1Preface
2. 2Chapter 1 — What CNI Is
3. 3Chapter 2 — Container Networking Fundamentals
4. 4Chapter 3 — The CNI Specification
5. 5Chapter 4 — CNI Plugins
6. 6Chapter 5 — IP Address Management (IPAM)
7. 7Chapter 6 — CNI in Kubernetes
8. 8Chapter 7 — The Major CNI Plugins
9. 9Chapter 8 — Network Policy
10. 10Chapter 9 — Performance and Dataplanes
11. 11Chapter 10 — Choosing and Operating CNI in Practice