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Install and Set Up kubectl

The Kubernetes command-line tool, kubectl, allows you to run commands against Kubernetes clusters. You can use kubectl to deploy applications, inspect and manage cluster resources, and view logs. For a complete list of kubectl operations, see Overview of kubectl.

Before you begin

You must use a kubectl version that is within one minor version difference of your cluster. For example, a v1.2 client should work with v1.1, v1.2, and v1.3 master. Using the latest version of kubectl helps avoid unforeseen issues.

Install kubectl on Linux

Install kubectl binary with curl on Linux

  1. Download the latest release with the command:

    curl -LO https://storage.googleapis.com/kubernetes-release/release/`curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt`/bin/linux/amd64/kubectl

    To download a specific version, replace the $(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt) portion of the command with the specific version.

    For example, to download version v1.18.0 on Linux, type:

    curl -LO https://storage.googleapis.com/kubernetes-release/release/v1.18.0/bin/linux/amd64/kubectl

  2. Make the kubectl binary executable.

    chmod +x ./kubectl

  3. Move the binary in to your PATH.

    sudo mv ./kubectl /usr/local/bin/kubectl

  4. Test to ensure the version you installed is up-to-date:

    kubectl version --client

Install using native package management


sudo apt-get update && sudo apt-get install -y apt-transport-https
curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -
echo "deb https://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee -a /etc/apt/sources.list.d/kubernetes.list
sudo apt-get update
sudo apt-get install -y kubectl


cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg
EOF
yum install -y kubectl

Install using other package management

If you are on Ubuntu or another Linux distribution that support snap package manager, kubectl is available as a snap application.

snap install kubectl --classic

kubectl version

If you are on Linux and using Homebrew package manager, kubectl is available for installation.

brew install kubectl

kubectl version

Install kubectl on macOS

Install kubectl binary with curl on macOS

  1. Download the latest release:

    curl -LO "https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/darwin/amd64/kubectl"

    To download a specific version, replace the $(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt) portion of the command with the specific version.

    For example, to download version v1.18.0 on macOS, type:

    curl -LO https://storage.googleapis.com/kubernetes-release/release/v1.18.0/bin/darwin/amd64/kubectl

  2. Make the kubectl binary executable.

    chmod +x ./kubectl

  3. Move the binary in to your PATH.

    sudo mv ./kubectl /usr/local/bin/kubectl

  4. Test to ensure the version you installed is up-to-date:

    kubectl version --client

Install with Homebrew on macOS

If you are on macOS and using Homebrew package manager, you can install kubectl with Homebrew.

  1. Run the installation command:

    brew install kubectl

    or

    brew install kubernetes-cli

  2. Test to ensure the version you installed is up-to-date:

    kubectl version --client

Install with Macports on macOS

If you are on macOS and using Macports package manager, you can install kubectl with Macports.

  1. Run the installation command:

    sudo port selfupdate
sudo port install kubectl

  2. Test to ensure the version you installed is up-to-date:

    kubectl version --client

Install kubectl on Windows

Install kubectl binary with curl on Windows

  1. Download the latest release v1.18.0 from this link.

    Or if you have curl installed, use this command:

    curl -LO https://storage.googleapis.com/kubernetes-release/release/v1.18.0/bin/windows/amd64/kubectl.exe

    To find out the latest stable version (for example, for scripting), take a look at https://storage.googleapis.com/kubernetes-release/release/stable.txt.

  2. Add the binary in to your PATH.

  3. Test to ensure the version of kubectl is the same as downloaded:

    kubectl version --client
Note: Docker Desktop for Windows adds its own version of kubectl to PATH. If you have installed Docker Desktop before, you may need to place your PATH entry before the one added by the Docker Desktop installer or remove the Docker Desktop’s kubectl.

Install with Powershell from PSGallery

If you are on Windows and using Powershell Gallery package manager, you can install and update kubectl with Powershell.

  1. Run the installation commands (making sure to specify a DownloadLocation):

    Install-Script -Name install-kubectl -Scope CurrentUser -Force
install-kubectl.ps1 [-DownloadLocation <path>]
    Note: If you do not specify a DownloadLocation, kubectl will be installed in the user’s temp Directory.

    The installer creates $HOME/.kube and instructs it to create a config file

  2. Test to ensure the version you installed is up-to-date:

    kubectl version --client
    Note: Updating the installation is performed by rerunning the two commands listed in step 1.

Install on Windows using Chocolatey or Scoop

To install kubectl on Windows you can use either Chocolatey package manager or Scoop command-line installer.

choco install kubernetes-cli

scoop install kubectl

  1. Test to ensure the version you installed is up-to-date:

    kubectl version --client

  2. Navigate to your home directory:

    cd %USERPROFILE%

  3. Create the .kube directory:

    mkdir .kube

  4. Change to the .kube directory you just created:

    cd .kube

  5. Configure kubectl to use a remote Kubernetes cluster:

    New-Item config -type file
    Note: Edit the config file with a text editor of your choice, such as Notepad.

Download as part of the Google Cloud SDK

You can install kubectl as part of the Google Cloud SDK.

  1. Install the Google Cloud SDK.

  2. Run the kubectl installation command:

    gcloud components install kubectl

  3. Test to ensure the version you installed is up-to-date:

    kubectl version --client

Verifying kubectl configuration

In order for kubectl to find and access a Kubernetes cluster, it needs a kubeconfig file, which is created automatically when you create a cluster using kube-up.sh or successfully deploy a Minikube cluster. By default, kubectl configuration is located at ~/.kube/config.

Check that kubectl is properly configured by getting the cluster state:

kubectl cluster-info

If you see a URL response, kubectl is correctly configured to access your cluster.

If you see a message similar to the following, kubectl is not configured correctly or is not able to connect to a Kubernetes cluster.

The connection to the server <server-name:port> was refused - did you specify the right host or port?

For example, if you are intending to run a Kubernetes cluster on your laptop (locally), you will need a tool like Minikube to be installed first and then re-run the commands stated above.

If kubectl cluster-info returns the url response but you can’t access your cluster, to check whether it is configured properly, use:

kubectl cluster-info dump

Optional kubectl configurations

Enabling shell autocompletion

kubectl provides autocompletion support for Bash and Zsh, which can save you a lot of typing.

Below are the procedures to set up autocompletion for Bash (including the difference between Linux and macOS) and Zsh.

Introduction

The kubectl completion script for Bash can be generated with the command kubectl completion bash. Sourcing the completion script in your shell enables kubectl autocompletion.

However, the completion script depends on bash-completion, which means that you have to install this software first (you can test if you have bash-completion already installed by running type _init_completion).

Install bash-completion

bash-completion is provided by many package managers (see here). You can install it with apt-get install bash-completion or yum install bash-completion, etc.

The above commands create /usr/share/bash-completion/bash_completion, which is the main script of bash-completion. Depending on your package manager, you have to manually source this file in your ~/.bashrc file.

To find out, reload your shell and run type _init_completion. If the command succeeds, you’re already set, otherwise add the following to your ~/.bashrc file:

source /usr/share/bash-completion/bash_completion

Reload your shell and verify that bash-completion is correctly installed by typing type _init_completion.

Enable kubectl autocompletion

You now need to ensure that the kubectl completion script gets sourced in all your shell sessions. There are two ways in which you can do this:

  • Source the completion script in your ~/.bashrc file:

    echo 'source <(kubectl completion bash)' >>~/.bashrc

  • Add the completion script to the /etc/bash_completion.d directory:

    kubectl completion bash >/etc/bash_completion.d/kubectl

  • If you have an alias for kubectl, you can extend shell completion to work with that alias:

    echo 'alias k=kubectl' >>~/.bashrc
echo 'complete -F __start_kubectl k' >>~/.bashrc
Note: bash-completion sources all completion scripts in /etc/bash_completion.d.

Both approaches are equivalent. After reloading your shell, kubectl autocompletion should be working.

Introduction

The kubectl completion script for Bash can be generated with kubectl completion bash. Sourcing this script in your shell enables kubectl completion.

However, the kubectl completion script depends on bash-completion which you thus have to previously install.

Warning: there are two versions of bash-completion, v1 and v2. V1 is for Bash 3.2 (which is the default on macOS), and v2 is for Bash 4.1+. The kubectl completion script doesn’t work correctly with bash-completion v1 and Bash 3.2. It requires bash-completion v2 and Bash 4.1+. Thus, to be able to correctly use kubectl completion on macOS, you have to install and use Bash 4.1+ (instructions). The following instructions assume that you use Bash 4.1+ (that is, any Bash version of 4.1 or newer).

Upgrade Bash

The instructions here assume you use Bash 4.1+. You can check your Bash’s version by running:

echo $BASH_VERSION

If it is too old, you can install/upgrade it using Homebrew:

brew install bash

Reload your shell and verify that the desired version is being used:

echo $BASH_VERSION $SHELL

Homebrew usually installs it at /usr/local/bin/bash.

Install bash-completion

Note: As mentioned, these instructions assume you use Bash 4.1+, which means you will install bash-completion v2 (in contrast to Bash 3.2 and bash-completion v1, in which case kubectl completion won’t work).

You can test if you have bash-completion v2 already installed with type _init_completion. If not, you can install it with Homebrew:

brew install bash-completion@2

As stated in the output of this command, add the following to your ~/.bashrc file:

export BASH_COMPLETION_COMPAT_DIR="/usr/local/etc/bash_completion.d"
[[ -r "/usr/local/etc/profile.d/bash_completion.sh" ]] && . "/usr/local/etc/profile.d/bash_completion.sh"

Reload your shell and verify that bash-completion v2 is correctly installed with type _init_completion.

Enable kubectl autocompletion

You now have to ensure that the kubectl completion script gets sourced in all your shell sessions. There are multiple ways to achieve this:

  • Source the completion script in your ~/.bashrc file:

    echo 'source <(kubectl completion bash)' >>~/.bashrc

  • Add the completion script to the /usr/local/etc/bash_completion.d directory:

    kubectl completion bash >/usr/local/etc/bash_completion.d/kubectl

  • If you have an alias for kubectl, you can extend shell completion to work with that alias:

    echo 'alias k=kubectl' >>~/.bashrc
echo 'complete -F __start_kubectl k' >>~/.bashrc

  • If you installed kubectl with Homebrew (as explained above), then the kubectl completion script should already be in /usr/local/etc/bash_completion.d/kubectl. In that case, you don’t need to do anything.

Note: the Homebrew installation of bash-completion v2 sources all the files in the BASH_COMPLETION_COMPAT_DIR directory, that’s why the latter two methods work.

In any case, after reloading your shell, kubectl completion should be working.

The kubectl completion script for Zsh can be generated with the command kubectl completion zsh. Sourcing the completion script in your shell enables kubectl autocompletion.

To do so in all your shell sessions, add the following to your ~/.zshrc file:

source <(kubectl completion zsh)

If you have an alias for kubectl, you can extend shell completion to work with that alias:

echo 'alias k=kubectl' >>~/.zshrc
echo 'complete -F __start_kubectl k' >>~/.zshrc

After reloading your shell, kubectl autocompletion should be working.

If you get an error like complete:13: command not found: compdef, then add the following to the beginning of your ~/.zshrc file:

autoload -Uz compinit
compinit

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