Technology · Ebook

OVN-Kubernetes: Software-Defined Networking for Kubernetes

by Shriira Press

OVN-Kubernetes is a CNI network plugin that gives Kubernetes a complete, programmable network built on Open Virtual Network (OVN) and Open vSwitch (OVS). Rather than stitching pods together with host routes and iptables, it models the cluster as logical switches, routers, and load balancers, then compiles that model down to OpenFlow on every node. This book starts with the Kubernetes network problem and the OVN and OVS foundations, then walks through the architecture — cluster manager, per-node controller, the northbound and southbound databases, ovn-northd, and ovn-controller. From there it covers pod connectivity, services as a kube-proxy replacement, NetworkPolicy via ACLs, gateway modes, the EgressIP, EgressFirewall, and EgressQoS controls, multi-homing with secondary networks, and operating the plugin in production. It is the default network for OpenShift and a CNCF project.

Contents

1. 1Preface
2. 2Chapter 1 — Why Kubernetes Needs a Real Network
3. 3Chapter 2 — OVN and OVS: The Foundations
4. 4Chapter 3 — The OVN-Kubernetes Architecture
5. 5Chapter 4 — Pod Networking and the Cluster Router
6. 6Chapter 5 — Services and Load Balancing
7. 7Chapter 6 — Network Policy and ACLs
8. 8Chapter 7 — Gateways and Egress Controls
9. 9Chapter 8 — Multi-Homing and Secondary Networks
10. 10Chapter 9 — OVN-Kubernetes in Practice