Certified Kubernetes Administrator (CKA) Study Guide

Chapter 2. Cluster Architecture, Installation, and Configuration

According to the name of the chapter, the first section of the curriculum refers to typical tasks you’d expect of a Kubernetes administrator. Those tasks include understanding the architectural components of a Kubernetes cluster, setting up a cluster from scratch, and maintaining a cluster going forward.

Interestingly, this section also covers the security aspects of a cluster, more specifically role-based access control (RBAC). You are expected to understand how to map permissions for operations to API resources for a set of users or processes.

At the end of this chapter, you will understand the tools and procedures for installing and maintaining a Kubernetes cluster. Moreover, you’ll know how to configure RBAC for representative, real-world use cases.

At a high level, this chapter covers the following concepts:

• Understanding RBAC

• Installing of a cluster with kubeadm

• Upgrading a version of a Kubernetes cluster with kubeadm

• Backing up and restoring etcd with etcdctl

• Understanding a highly available Kubernetes cluster

Role-Based Access Control

In Kubernetes you need to be authenticated before you are allowed to make a request to an API resource. A cluster administrator usually has access to all resources and operations. The easiest way to operate a cluster is to provide everyone with an admin account. While “admin access for everyone” sounds fantastic as you grow your business, it comes with a considerable ...