Launching your First Kubernetes Cluster with Nginx running

TABLE OF CONTENTS

What is minikube?
Features of minikube
Define Pod
Types of Installation of K8s
Task 1: Install minikube on your local
Task 2: Create your first pod on Kubernetes through minikube.
Task 3: Create NGINX pod on K8s through Kubeadm
Create the Nginx Pod

What is minikube?

• Minikube is a tool that quickly sets up a local Kubernetes cluster on macOS, Linux, and Windows. It can deploy as a VM, a container, or on bare metal.
• Minikube is a pared-down version of Kubernetes that gives you all the benefits of Kubernetes with a lot less effort.
• This makes it an interesting option for users who are new to containers, and also for projects in the world of edge computing and the Internet of Things.

Features of minikube

1. Supports the latest Kubernetes release (+6 previous minor versions)
2. Cross-platform (Linux, macOS, Windows)
3. Deploy as a VM, a container, or on bare-metal
4. Multiple container runtimes (CRI-O, containerd, docker)
5. Direct API endpoint for blazing-fast image load and build
6. Advanced features such as LoadBalancer, filesystem mounts, FeatureGates, and network policy
7. Addons for easily installed Kubernetes applications
8. Supports common CI environments.

Define Pod

• Pods are the smallest deployable units of computing that you can create and manage in Kubernetes.
• A Pod (as in a pod of whales or pea pod) is a group of one or more containers, with shared storage and network resources, and a specification for how to run the containers.
• A Pod’s contents are always co-located and co-scheduled, and run in a shared context. A Pod models an application-specific “logical host”: it contains one or more application containers that are relatively tightly coupled.

Types of Installation of K8s

1. Mini Kube (Docker Inside Docker DIND) → least use in Prod → Easiest
2. Kubeadm :→ Baremetal (open-source tool) → Used in Prod → Intermediate
3. Managed K8s Cluster

AWS → EKS (Elastic Cloud Kubernetes)

Azure → AKS (Azure Kubernetes Service)

GCP → GKE (Google Kubernetes Engine)

4. KIND (Kubernetes in Docker)

Task 1: Install minikube on your local

1. Create a new VM instance having 2 CPUs, 4GB of free memory, 20 GB of free disk space.

When creating a new EC2 instance select t2.medium.

2. Install Docker in your system.

  sudo apt update -y
  sudo apt install docker.io -y

  sudo systemctl start docker
  sudo systemctl enable docker
  sudo systemctl status docker

Add the user to the docker group

  sudo usermod -aG docker $USER && newgrp docker

3. Install Minikube in system.

  curl -LO https://storage.googleapis.com/minikube/releases/latest/minikube-linux-amd64

  sudo install minikube-linux-amd64 /usr/local/bin/minikube

4. And then install Kubelet.

  sudo snap install kubectl --classic

5. Start Minikube as per the image and check Minikube status

  minikube start --driver=docker

6. Check if minikube cluster has been set up successfully or not by checking pods or namespace status.

  kubectl get pods

  kubectl get namespace

Task 2: Create your first pod on Kubernetes through minikube.

1. To create a pod, we have to write a YAML file which is a.k.a Manifest file. So to create a pod for NGINX we have to pass the values & attributes in key-value format.

In the manifest file, we are passing values:

apiVersion → Kubernetes Version

Kind → Type of deployment

metadata → More Details about pod

container → Details of containers in object

containerPort → The port where the pod will deploy

  apiVersion: v1
  kind: Pod
  metadata:
    name: nginx
  spec:
    containers:
    - name: nginx
      image: nginx:1.14.2
      ports:
      - containerPort: 80

2. Run the kubectl command to create a pod.

  kubectl apply -f pod.yml

3. Check the pod’s status by kubectl get pods, you can see a NGINX pod is created successfully by it’s status

  kubectl get pods

4. Run the kubectl get pods -o wide command to get more detailed information about the pod-like IP, node, age of node, and status.

5. To check if nginx is running locally or not, do we have to ssh the minikube go inside the minikube cluster. Then curl the IP address of the pod.

  #Get the IP
  kubectl get pods -o wide

  # SSH into minikube
  minikube ssh

  # Curl the IP address to access the NGINX
  curl http://<IP-Addr>

Task 3: Create NGINX pod on K8s through Kubeadm

1. Create 2 VM instances for Master and Node.

2. Install Docker on both Master & Node

  sudo apt update -y
  sudo apt install docker.io -y

  sudo systemctl start docker
  sudo systemctl enable docker
  sudo systemctl status docker

3. Install Kebeadm on both master and node.

  sudo curl -fsSLo /usr/share/keyrings/kubernetes-archive-keyring.gpg https://packages.cloud.google.com/apt/doc/apt-key.gpg

  echo "deb [signed-by=/usr/share/keyrings/kubernetes-archive-keyring.gpg] https://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee /etc/apt/sources.list.d/kubernetes.list

4. Again update the system.

  sudo apt update -y

5. Install Kubeadm,Kubectl and Kebelet in both Master and Node.

  sudo apt install kubeadm=1.20.0-00 kubectl=1.20.0-00 kubelet=1.20.0-00 -y

6. Connect Master with Node:

Initialized Kubeadm:

Run the following command only on Master:

  sudo su
  kubeadm init

7. Setup the kubeconfig for the current user

  mkdir -p $HOME/.kube
  sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
  sudo chown $(id -u):$(id -g) $HOME/.kube/config

8. Finish the Master Setup using the following Command:

  kubectl apply -f https://github.com/weaveworks/weave/releases/download/v2.8.1/weave-daemonset-k8s.yaml

9. Now create a token to join the Master & Node connection

  kubeadm token create --print-join-command

10. We will get nodes for master

11. After that open port 6443 in master

12. Then on the Worker Node reset the checks so it can’t assign as Master.

sudo su
kubeadm reset pre-flight checks

13. Paste the Join command on the worker node and append — v=5 at the end

14. Verify by running the command in Master:

kubectl gets nodes

Kubeadm Installation Step

Create the Nginx Pod

1. By default, the kubectl run command creates a deployment and a replica set along with the pod. If you only want to create a pod without creating a deployment or replica set, you can use the — restart=Never flag.
2. But if you pass — restart=Always, if your pod is deleted or having an issue, then a new pod will be replaced immediately.

  kubectl run nginx --image=nginx --restart=Never

3. Now we can see the docker container in the worker node

  docker ps

4. To check if the pods are running or not

  kubectl get pods

5. Get the details of the pod

  kubectl get pods -o wide

6. To delete a pod in

  # kubectl delete pod  <pod-name>
  kubectl delete pod nginx

In this blog, we explored setting up a Kubernetes cluster using Minikube and creating a pod within it. If you have questions or want to share your experiences, please leave a comment below. Stay tuned for more blogs and connect with me on LinkedIn for further discussions.

I’m always open to feedback and suggestions for improving my content. You can find me on LinkedIn as Mudit Mathur. Feel free to reach out with your thoughts.

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