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)
1
Section 1: Getting Started with kubectl
3
Section 2: Kubernetes Cluster and Node Management
6
Section 3: Application Management
10
Section 4: Extending kubectl

Chapter 1: Introducing and Installing kubectl

Kubernetes is an open source container orchestration system for managing containerized applications across multiple hosts in a cluster.

Kubernetes provides mechanisms for application deployment, scheduling, updating, maintenance, and scaling. A key feature of Kubernetes is that it actively manages containers to ensure that the state of the cluster always matches the user's expectations.

Kubernetes enables you to respond quickly to customer demand by scaling or rolling out new features. It also allows you to make full use of your hardware.

Kubernetes is the following:

  • Lean: Lightweight, simple, and accessible
  • Portable: Public, private, hybrid, and multi-cloud
  • Extensible: Modular, pluggable, hookable, composable, and toolable
  • Self-healing: Auto-placement, auto-restart, and auto-replication

Kubernetes builds on a decade and a half of experience at Google running production workloads at scale, combined with best-of-breed ideas and best practices from the community:

Figure 1.1 – A 10,000-foot view of Kubernetes' architecture

Figure 1.1 – A 10,000-foot view of Kubernetes' architecture

One of the ways to manage Kubernetes clusters is kubectl—Kubernetes' command-line tool for management, it is a tool for accessing a Kubernetes cluster that allows you to run different commands against Kubernetes clusters to deploy apps, manage nodes, troubleshoot deployments, and more.

In this chapter, we're going to cover the following main topics:

  • Introducing kubectl
  • Installing kubectl
  • kubectl commands