Book Image

kubectl: Command-Line Kubernetes in a Nutshell

By : Rimantas Mocevicius
Book Image

kubectl: Command-Line Kubernetes in a Nutshell

By: Rimantas Mocevicius

Overview of this book

The kubectl command line tool lets you control Kubernetes clusters to manage nodes in the cluster and perform all types of Kubernetes operations. This introductory guide will get you up to speed with kubectl in no time. The book is divided into four parts, touching base on the installation and providing a general overview of kubectl in the first part. The second part introduces you to managing Kubernetes clusters and working with nodes. In the third part, you’ll be taken through the different ways in which you can manage Kubernetes applications, covering how to create, update, delete, view, and debug applications. The last part of the book focuses on various Kubernetes plugins and commands. You’ll get to grips with using Kustomize and discover Helm, a Kubernetes package manager. In addition to this, you’ll explore how you can use equivalent Docker commands in kubectl. By the end of this book, you’ll have learned how to install and update an application on Kubernetes, view its logs, and inspect clusters effectively.
Table of Contents (16 chapters)
Section 1: Getting Started with kubectl
Section 2: Kubernetes Cluster and Node Management
Section 3: Application Management
Section 4: Extending kubectl

Chapter 5: Updating and Deleting Applications

In the previous chapter, we learned how to deploy an application and its service and how to scale deployment replicas up. Let's now learn about some more advanced ways to update your application.

In this chapter, we're going to learn how to update applications to new versions and, if the release was a bad one, how to roll it back. We will see how to assign an application to a particular node, running applications in high-availability mode, how to make applications available over the internet, and in cases where there is a need, how to delete an application.

We're going to cover the following main topics in this chapter:

  • Releasing a new application version
  • Rolling back an application release
  • Assigning an application to a specific node (node affinity)
  • Scheduling application replicas to different nodes (pod affinity)
  • Exposing an application to the internet
  • Deleting an application