The kubectl is a vital tool when managing Kubernetes. This tool occupies the engineer’s life and is hence worth spending time configuring it for an efficient and productive environment. There are several commands one can use when managing the Kubernetes resources via kubectl. These include; kubectl get pod, kubectl logs pod_name e.t.c

kube-ps1 is a Kubernetes Bash/Zsh prompt that can be used to display the current cluster and namespace. In other words, it allows you to add the current Kubernetes context and namespace to your Bash/Zsh prompt strings. It aims to simplify the use of kubectl, inspired by several tools.

This guide aims to demonstrate how to configure the Kubernetes prompt for bash and zsh using kube-ps1. I assume that you already have a Kubernetes cluster set up. There are several ways to deploy the cluster as illustrated in the below guides:

• Deploy K0s Kubernetes Cluster on Linux using K0sctl
• Deploy Kubernetes Cluster on Oracle Linux 8 with Kubeadm
• Install Kubernetes on Alpine Linux with k3s
• Deploy Kubernetes Cluster on Rocky Linux 9 using k0s
• Deploy k0s Kubernetes Cluster on Ubuntu

Once the cluster is set up, you need to install kubectl.

curl -LO "https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/linux/amd64/kubectl"
chmod +x kubectl
sudo mv kubectl /usr/local/bin

For k0s, use the generated certificate to access the cluster.

export KUBECONFIG=/var/lib/k0s/pki/admin.conf

Install kube-ps1 on your System

kube-ps1 can be installed on several platforms as shown below:

• On macOS:

Install kube-ps1 using Homebrew:

brew update
brew install kube-ps1

• On Linux/macOS:

You can also install kube-ps1 using a source file. Install git tool

### Ubuntu / Debian ###
sudo apt update
sudo apt install git

###CentOS / Fedora ###
sudo yum -y install git

First, clone the repository below:

cd ~/
git clone https://github.com/jonmosco/kube-ps1.git

Source kube-ps1.sh in the directory(kube-ps1) to Bash/Zsh:

$ vim ~/.bashrc #for Bash
source "/home/$USER/kube-ps1/kube-ps1.sh"
PS1='[\u@\h \W $(kube_ps1)]\$ '

$ vim ~/.zshrc #for ZSH
source "/home/$USER/kube-ps1/kube-ps1.sh"
PS1='[\u@\h \W $(kube_ps1)]\$ '

The /home on macOS is equivalent to /Users.

kube-ps1 works best with kubens and kubectx. They can be installed with the command:

sudo git clone https://github.com/ahmetb/kubectx /opt/kubectx
sudo ln -s /opt/kubectx/kubectx /usr/local/bin/kubectx
sudo ln -s /opt/kubectx/kubens /usr/local/bin/kubens

Source your bashrc file:

source  ~/.bashrc

Using kube-ps1 to Configure Kubernetes prompt for bash and zsh

Now you can use kube-ps1 to configure Kubernetes prompt for bash and zsh. Switch the namespace:

kubens kube-public

Toggle kube-ps1 on and off:

kubeoff
kubeon

Sample Output:

You can also use the below commands to turn on/off kube-ps1 globally:

kubeon -g
kubeoff -g

Customize kube-ps1

There are several environment variables that can be used to customize kube-ps1.

The table below shows the available environment variable and their use:

Environment Variable	Default	Meaning
KUBE_PS1_NS_ENABLE	true	Display the namespace. If set to false, this will also disable KUBE_PS1_DIVIDER
KUBE_PS1_DIVIDER	:	The separator between context and namespace
KUBE_PS1_BINARY	kubectl	Default Kubernetes binary
KUBE_PS1_CLUSTER_FUNCTION	No default, must be user-supplied	Function to customize how cluster is displayed
KUBE_PS1_SYMBOL_PADDING	true	Adds a space (padding) after the symbol to prevent clobbering prompt characters
KUBE_PS1_SYMBOL_DEFAULT	⎈	Default prompt symbol. Unicode \u2388
KUBE_PS1_SYMBOL_USE_IMG	false	Unicode \u2638 as the prompt symbol
KUBE_PS1_SEPARATOR	|	The separator between symbol and context name
KUBE_PS1_PREFIX	(	Prompt opening character
KUBE_PS1_SUFFIX	)	Prompt closing character
KUBE_PS1_NAMESPACE_FUNCTION	No default, it must be user-supplied	Function to customize how the namespace is displayed
KUBE_PS1_SYMBOL_ENABLE	true	Display the prompt Symbol. If set to false, this will also disable KUBE_PS1_SEPARATOR

Proceed and make customizations to kube-ps1

For example, use the below command and see what happens:

KUBE_PS1_SYMBOL_USE_IMG=true

Sample output:

Change the prefix and suffix

KUBE_PS1_PREFIX={
KUBE_PS1_SUFFIX=}

Sample Output:

To disable a feature, provide an empty string. For example:

KUBE_PS1_SEPARATOR=''

Set kube-ps1 Colors

The table below shows the variable to set colors and the default values:

Variable	Default	Meaning
KUBE_PS1_PREFIX_COLOR	null	Set the default color of the prompt prefix
KUBE_PS1_CTX_COLOR	red	Set the default color of the context
KUBE_PS1_SYMBOL_COLOR	blue	Set the default color of the Kubernetes symbol
KUBE_PS1_BG_COLOR	cyan	Set default color of the namespace
KUBE_PS1_SUFFIX_COLOR	null	Set the default color of the prompt suffix
KUBE_PS1_NS_COLOR	cyan	Set the default color of the namespace

To set a color, execute the correct variable. For example, setting the prefix and suffix colors to yellow, the commands will be:

KUBE_PS1_PREFIX_COLOR=yellow
KUBE_PS1_SUFFIX_COLOR=yellow

Execution output:

Set the context color.

KUBE_PS1_CTX_COLOR=magenta

Sample Output:

If you want to disable the color, provide an empty string. For example;

KUBE_PS1_CTX_COLOR=''

Output:

The colors names available are black, green, blue, red, cyan, magenta, and yellow. Other 256 colors are also available by specifying the numerical value as the variable.

That marks the end of this brief guide on how to configure the Kubernetes prompt for bash and zsh using kube-ps1. I hope this was valuable.

• Install MicroK8s Kubernetes Cluster on Arch|Manjaro|Garuda
• How To Install Kubernetes Cluster on Ubuntu
• Deploy Kubernetes Cluster on Oracle Linux with Kubeadm