Book Image

Kubernetes – An Enterprise Guide - Second Edition

By : Marc Boorshtein, Scott Surovich
Book Image

Kubernetes – An Enterprise Guide - Second Edition

By: Marc Boorshtein, Scott Surovich

Overview of this book

Kubernetes has taken the world by storm, becoming the standard infrastructure for DevOps teams to develop, test, and run applications. With significant updates in each chapter, this revised edition will help you acquire the knowledge and tools required to integrate Kubernetes clusters in an enterprise environment. The book introduces you to Docker and Kubernetes fundamentals, including a review of basic Kubernetes objects. You’ll get to grips with containerization and understand its core functionalities such as creating ephemeral multinode clusters using KinD. The book has replaced PodSecurityPolicies (PSP) with OPA/Gatekeeper for PSP-like enforcement. You’ll integrate your container into a cloud platform and tools including MetalLB, externalDNS, OpenID connect (OIDC), Open Policy Agent (OPA), Falco, and Velero. After learning to deploy your core cluster, you’ll learn how to deploy Istio and how to deploy both monolithic applications and microservices into your service mesh. Finally, you will discover how to deploy an entire GitOps platform to Kubernetes using continuous integration and continuous delivery (CI/CD).
Table of Contents (17 chapters)
15
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16
Index

Exploring the control plane

As its name suggests, the control plane controls every aspect of a cluster. If your control plane goes down, you can probably imagine that your cluster will encounter issues. Without a control plane, a cluster will not have any scheduling abilities, which means that workloads that are running will remain running unless they are stopped and restarted. Since the control plane is extremely important, it is always suggested that you have at least three master nodes. Many production installations run more than three master nodes, but the number of installed nodes should always be an odd number. Let's look at why the control plane and its components are so vital to a running cluster by examining each one.

The Kubernetes API server

The first component to understand in a cluster is the kube-apiserver component. Since Kubernetes is application programming interface (API)-driven, every request that comes into a cluster goes through the API server. Let...