K8s-Create a local cluster

In this article, we will walk through how provisioning a local Kubernetes cluster (single node or multiple nodes).

kind architecture

The next part will guide you to provision a Kubernetes cluster on cloud (Azure or GCP).

1. Minikube

Minikube is local Kubernetes, focusing on making it easy to learn and develop for Kubernetes.

Download minikube for Linux:

curl -LO https://storage.googleapis.com/minikube/releases/latest/minikube-linux-amd64
sudo install minikube-linux-amd64 /usr/local/bin/minikube

Set minikube driver: minikube config set driver docker. You can use other drivers (VirtualBox, Hyper-V,…) if you want.
Start minikube: minikube start
Your cluster is up and running
Let’s try to create a pod and a service

kubectl create deployment nginx --image=nginx --port=80 --replicas=1
kubectl expose deployment nginx --port=80
kubectl get svc

Get service url by running: minikube service nginx. Your pod is accessible at this url: http://127.0.0.1:38003.

create pod on minikube

Minikube is easy to setup but it’s not supported yet for creating a multi-nodes cluster (multi master nodes and worker nodes). For this use case, you can consider Kind.

2. Kubernetes in Docker (kind)

kind is a tool for running local Kubernetes clusters using Docker container “nodes”.

kind architecture

Prerequisites:

Docker must be installed. If it is not the case, you can download this convenience script to install Docker on your machine: https://docs.docker.com/engine/install/ubuntu/
kubectl: https://kubernetes.io/docs/tasks/tools/install-kubectl-linux/

Installation:

Download kind for Linux

export kind_version=v0.11.1
curl -Lo ./kind https://kind.sigs.k8s.io/dl/$kind_version/kind-linux-amd64
chmod +x ./kind
sudo mv ./kind /usr/local/bin

Verify if kind is installed by running this command: kind version

Provision a cluster with 3 master nodes and 3 worker nodes:

create a yaml file describing your cluster named multi-node-master.yaml with the below content:

kind: Cluster
apiVersion: kind.x-k8s.io/v1alpha4
nodes:
- role: control-plane
- role: control-plane
- role: control-plane
- role: worker
- role: worker
- role: worker

run this command to create your cluster:

kind create cluster --name kind-cluster --config multi-node-master.yaml

create a kind cluster

Once this is done, you have kubeconfig ready for use located at ~/.kube/config
Get the cluster’s information:

kubectl cluster-info

Kubernetes control plane is running at https://127.0.0.1:34271
CoreDNS is running at https://127.0.0.1:34271/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy

Switch kubectl context to the new created context: kubectl cluster-info –context kind-kind-cluster
Now, verify your nodes:

kubectl get nodes

NAME                             STATUS   ROLES                  AGE     VERSION
kind-cluster-control-plane    Ready    control-plane,master   3m37s   v1.21.1
kind-cluster-control-plane2   Ready    control-plane,master   3m16s   v1.21.1
kind-cluster-control-plane3   Ready    control-plane,master   2m9s    v1.21.1
kind-cluster-worker           Ready    <none>                 113s    v1.21.1
kind-cluster-worker2          Ready    <none>                 114s    v1.21.1
kind-cluster-worker3          Ready    <none>                 113s    v1.21.1

Everything is good. Let’s try to create a pod.

kubectl run nginx --image=nginx

kubectl get pod -o wide
NAME    READY   STATUS    RESTARTS   AGE   IP           NODE                      NOMINATED NODE   READINESS GATES
nginx   1/1     Running   0          49s   10.244.3.2   kind-cluster-worker2   <none>           <none>

Well done! Your pod is scheduled on the worker node 2.

3. Lens

If you need a tool to visualize/manage your k8s cluster (local and remote) using UI, Lens is may be a good option. It is built on open source and free.

Tips for installing Lens for Windows and connect it to WSL2 (Windows Sub System for Linux):

Download Lens for Windows and install it
Go to File–>Preferences–>Application: set terminal shell path to wsl.exe
Go to File–> Add Cluster then copie and paste the kubeconfig located at ~/.kube/config
Lens will show you the new clusters found
Click on the connect button on the cluster of your choice
Now, Lens could see your cluster on WSL2:
From this screen, open a new terminal session (+ button at the bottom) and then run this command:

export KUBECONFIG=~/.kube/config

Now, you can use kubectl as usual directly from Lens integrated command line: kubectl get nodes

4. k9s

k9s is a terminal-based UI to manage Kubernetes clusters that aims to simplify navigating, observing, and managing your applications in K8s. K9s continuously monitors Kubernetes clusters for changes and provides shortcut commands to interact with the observed resources.

Installation:

Download k9s for Linux:

k9s_version=v0.24.15
sudo wget -qO- https://github.com/derailed/k9s/releases/download/$k9s_version/k9s_Linux_x86_64.tar.gz | tar zxvf -  -C /tmp/
sudo mv /tmp/k9s /usr/local/bin

Command mode is “:”
Start k9s by running: k9s
View all context: press “:” then ctx (:ctx)
View all namespaces: press “:” then ns (:ns)
View pods: press “:” then pod (:pod)
- View yaml file: press “y”
- View logs: press “l” or “p” (log previous)
- Edit yaml file: press “e”
- Open a shell session inside of pod: press “s”
View deployments: press “:” then deploy (:deploy)
- Describe deployment: press “d”
- Edit deployment: press “e”
- View logs: press “l” or “p” (log previous)
- Restart deployment: press ctrl-t
- Delete deployment: press ctrl-d
- Scale deployment: press “s” on selected deployment
Search mode: press “/”
- view resources of default namespace: /default
- filter pod with specific label: / -l app=nginx
Xray pod: press xray then pod (xray pod)