Containerized Stateless Applications using Kubernetes

Overview

Assignment: Hosting Containerized Application on KIND Cluster in AWS EC2

Overview

In this assignment, the goal is to host a containerized application on a KIND (Kubernetes IN Docker) cluster running on an Amazon Linux-based EC2 instance in the AWS environment. The assignment flow includes the following steps:

1. Deploy Amazon Linux EC2 Instance: Provision an Amazon Linux-based EC2 instance with sufficient capacity to run the KIND cluster and host the containerized application.

2. Install Pre-requisites: Install all the necessary pre-requisites on the Amazon EC2 instance required to host the containerized application on the Kubernetes cluster created by KIND (kind, kubectl).

3. Create KIND Cluster: Use the KIND tool to create a Kubernetes cluster.

4. Deploy Containerized Application: Deploy the containerized application using pod, replicaset, deployment, and service manifests.

5. Expose Web Application: Expose the web application using a Service of type NodePort.

6. Expose MySQL: Expose MySQL using a Service of type ClusterIP.

7. Update Applications: Update the applications and deploy the new version of the application.

Tools and Services Used

• Amazon ECR: Securely store your container images.
• Cloud9 IDE (or your local environment): Develop your application and build container images.
• Amazon EC2: Host your KIND cluster.
• KIND: Deploy a local Kubernetes cluster.
• Kubectl: Communicate with the Kubernetes API Server.
• AWS IAM (Identity and Access Management): Grant EC2 instance access to Amazon ECR repository.
• Terraform: Optionally deploy the infrastructure.

Step 1: Docker Installation

sudo yum update -y
sudo yum install docker -y
sudo systemctl start docker
sudo systemctl status docker

Step 2: Creating Access

sudo chmod 666 /var/run/docker.sock
sudo usermod -a -G docker ec2-user
aws configure
sudo vi ~/.aws/credentials
aws docker image push command
chmod 777 ./init_kind.sh 
./init_kind.sh

Step 3: Testing Local cluster

kubectl get nodes
kubectl cluster-info

Step 4: Creating Namespace

kubectl create ns app-ns
kubectl create ns mysql-ns

Step 5: Creating Pod

kubectl apply -f app-pod.yaml 
kubectl apply -f mysql-pod.yaml 
kubectl apply -f app-service.yaml 
kubectl apply -f mysql-service.yaml

Step 6: Retriving pods & Service

kubectl get pods -n app-ns
kubectl get pods -n mysql-ns
kubectl get services -n app-ns
kubectl get services -n mysql-ns

Step 7: Connecting services

kubectl exec -it application-pod -n app-ns  -- /bin/sh 
kubectl port-forward -n app-ns pod/application-pod 8080:8080
curl localhost:8080
kubectl logs application-pod -n app-ns
kubectl logs mysql-pod -n mysql-ns

Step 8: Creating Replica Set

kubectl apply -f app-replica.yaml
kubectl apply -f mysql-replica.yaml
kubectl get rs -n app-ns
kubectl get rs -n mysql-ns
kubectl get pods -n app-ns
kubectl get pods -n mysql-ns

Step 9: Deployment

kubectl apply -f app-deployment.yaml
kubectl apply -f mysql-deployment.yaml 
kubectl get deployments -n app-ns
kubectl get deployments  -n mysql-ns
kubectl get pods -n app-ns
publicip:30000

Step 10: Deployment Version Change

kubectl rollout history deployment application -n app-ns
kubectl get pods -n app-ns
kubectl get pods -n mysql-ns

DELETE

kubectl delete services --all 
kubectl delete pods --all