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

Using Helm's linting feature

So far, we've learned how to create a Helm chart. However, we also need to know how to check the chart for possible issues and errors. For that, we can use the helm lint <CHART NAME> command, which will check the Helm chart content by running a series of tests to verify the chart integrity.

Let's lint the nginx chart we have created:

$ helm lint nginx

The output of the preceding command is shown in the following screenshot:

Figure 9.19 – Linting the nginx chart

As you can see in the preceding screenshot, our chart has no issues and can be installed safely. The [INFO] message is just the warning that the chart's icon is missing, which can be safely ignored.

It is really recommend to have it if you want to host your charts for example in where it gets shown in its UI.