Book Image

Certified Kubernetes Administrator (CKA) Exam Guide

By : Mélony Qin
4 (1)
Book Image

Certified Kubernetes Administrator (CKA) Exam Guide

4 (1)
By: Mélony Qin

Overview of this book

Kubernetes is the most popular container orchestration tool in the industry. The Kubernetes Administrator certification will help you establish your credibility and enable you to efficiently support the business growth of individual organizations with the help of this open source platform. The book begins by introducing you to Kubernetes architecture and the core concepts of Kubernetes. You'll then get to grips with the main Kubernetes API primitives, before diving into cluster installation, configuration, and management. Moving ahead, you’ll explore different approaches while maintaining the Kubernetes cluster, perform upgrades for the Kubernetes cluster, as well as backup and restore etcd. As you advance, you'll deploy and manage workloads on Kubernetes and work with storage for Kubernetes stateful workloads with the help of practical scenarios. You'll also delve into managing the security of Kubernetes applications and understand how different components in Kubernetes communicate with each other and with other applications. The concluding chapters will show you how to troubleshoot cluster- and application-level logging and monitoring, cluster components, and applications in Kubernetes. By the end of this Kubernetes book, you'll be fully prepared to pass the CKA exam and gain practical knowledge that can be applied in your day-to-day work.
Table of Contents (17 chapters)
1
Part 1: Cluster Architecture, Installation, and Configuration
5
Part 2: Managing Kubernetes
10
Part 3: Troubleshooting

Working with etcd

Cluster data is stored in a key-value store in a Kubernetes cluster called etcd. The cluster data includes cluster state information such as pod state data, node state data, and configurations. As this data is critical for Kubernetes to orchestrate the workloads to the desired state, it stands to reason that it should be backed up periodically.

To access the etcd cluster inside the Kubernetes cluster, we can run the following command:

  kubectl get po -n kube-system

This will list all the pods currently running in the kube-system namespace:

Figure 3.7 – Check the current etcd pod status

In the following sections, we’ll take a closer look at the etcd cluster pod and learn all the related information that will be useful in the actual CKA exam.

Exploring the ETCD cluster pod

To get a closer look at the etcd pod that we have, use the following command:

  kubectl describe po <etcd-podname...