kubectl CLI installation and configuration in Kubernetes - Commands & Configuration

Introduction

kubectl is a command-line tool that lets you talk to Kubernetes clusters. It helps you manage and control your applications running in Kubernetes by sending commands to the cluster.

When you want to create or delete applications in a Kubernetes cluster.

When you need to check the status of your running containers and pods.

When you want to update or change the configuration of your Kubernetes resources.

When you need to troubleshoot issues by viewing logs or describing resources.

When you want to switch between different Kubernetes clusters or namespaces.

Commands

Download the latest stable kubectl binary for Linux to your current directory.

Terminal

curl -LO https://dl.k8s.io/release/v1.27.3/bin/linux/amd64/kubectl

Expected Output

No output (command runs silently)

Make the downloaded kubectl binary executable so you can run it.

Terminal

chmod +x kubectl

Expected Output

No output (command runs silently)

Move the kubectl binary to a directory in your system PATH so you can run it from anywhere.

Terminal

sudo mv kubectl /usr/local/bin/

Expected Output

No output (command runs silently)

Check that kubectl is installed correctly and see its version.

Terminal

kubectl version --client

Expected Output

Client Version: v1.27.3

→

--client - Show only the client version without connecting to a cluster

Display the current Kubernetes configuration, showing clusters, users, and contexts kubectl knows about.

Terminal

kubectl config view

Expected Output

apiVersion: v1

clusters:

- cluster:

    server: https://example-cluster-api-server

  name: example-cluster

contexts:

- context:

    cluster: example-cluster

    user: example-user

  name: example-context

current-context: example-context

kind: Config

preferences: {}

users:

- name: example-user

  user:

    token: example-token

Key Concept

If you remember nothing else, remember: kubectl is your main tool to communicate with Kubernetes clusters by sending commands and managing configurations.

Common Mistakes

Not making the kubectl binary executable after downloading.

Without execute permission, the system won't let you run kubectl commands.

Always run 'chmod +x kubectl' after downloading the binary.

Not moving kubectl to a directory in the system PATH.

If kubectl is not in the PATH, you must specify its full path every time, which is inconvenient.

Move kubectl to /usr/local/bin or another PATH directory using 'sudo mv kubectl /usr/local/bin/'.

Running 'kubectl version' without '--client' before configuring access to a cluster.

kubectl tries to connect to a cluster and fails if no cluster is configured, causing confusing errors.

Use 'kubectl version --client' to check installation without needing cluster access.

Summary

Download the kubectl binary for your operating system.

Make the binary executable and move it to a directory in your system PATH.

Verify the installation by checking the client version.

View your current Kubernetes configuration with 'kubectl config view'.