Deploying a Three-Tier Application on AWS with Kubernetes - A Step-by-Step Guide

In this tutorial, we'll embark on a journey to deploy a three-tier application on AWS using Kubernetes. This comprehensive guide will walk you through each step, ensuring a smooth deployment process.

Step 1: Launch an EC2 Instance

1.1 Create an EC2 Instance

1. Navigate to the AWS Management Console by visiting AWS Console.

2. Click on "Services" and select "EC2" under the "Compute" section to access the EC2 Dashboard.

3. Click on "Launch Instance" and follow the wizard to create an instance.

   • Choose an Amazon Machine Image (AMI) (e.g., UBUNTU AMI).

   • Select an instance type (e.g., t2.micro).

   • Configure instance details, including network settings and security groups. Ensure to open inbound port 3000 to allow traffic to your application.

   • Review and launch the instance.

     

1.2 Connect to the Instance

1. Once your instance is running, select it from the EC2 dashboard.

2. Click on "Connect" to get instructions on how to connect using SSH.

3. Use the provided SSH command (e.g., ssh -i key.pem ec2-user@public-ip) to connect to your instance.

Step 2: Clone the Repository

2.1 Clone the Repository

1. Open a terminal on your EC2 instance.

2. Run the following commands:

    git clone https://github.com/VedThavkar/TWSThreeTierAppChallenge
    cd TWSThreeTierAppChallenge
   

Step 3: Dockerize the Frontend

3.1 Install Docker

1. Update package lists:

    sudo apt-get update
   

2. Install Docker:

    sudo apt install docker.io
    sudo chown $USER /var/run/docker.sock
   

3.2 Create Dockerfile for Frontend

1. Create a Dockerfile for the frontend application using your favorite text editor.

    #Dockerfile
    # Example Dockerfile
    FROM node:14
    WORKDIR /usr/src/app
    COPY package*.json ./
    RUN npm install
    COPY . .
    CMD ["npm", "start"]
   

   

3.3 Build and Run the Docker Image

1. Build the Docker image:

    docker build -t threetier-frontend:latest .
   

   

2. Run the Docker container:

    docker run -d -p 3000:3000 threetier-frontend:latest
   

   

3.4 Test the Frontend

1. Open your web browser and navigate to http://<EC2-public-ip>:3000.

   • Verify that the frontend application is running successfully.

     

we have done with the frontend testing, now for the time being we can kill the container.

Next step is to install AWS CLI, but for that we need a user. So, we will navigate to the IAM service and create a user there with Administrator access. and 16. Create Security Credentials for AWS CLI.

Step 4: Install AWS CLI and Push Frontend Image to ECR

4.1 Install AWS CLI

1. Install the AWS CLI on your EC2 instance.

    curl "https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip" -o "awscliv2.zip"
    sudo apt install unzip
    unzip awscliv2.zip
    sudo ./aws/install -i /usr/local/aws-cli -b /usr/local/bin --update
   

2. Configure the AWS CLI:

    aws configure
   

   

   Follow the prompts to enter your AWS credentials, default region, and output format.

4.2 Create ECR Repository

1. Open the AWS Management Console.

2. Navigate to Amazon ECR and click "Create repository".

3. Enter a repository name and create the repository.

   

4.3 Push Frontend Image to ECR

1. Follow the ECR instructions to log in to the registry.

   

2. Push the frontend Docker image to the ECR repository.

   

   

Step 5: Dockerize the Backend

5.1 Create Dockerfile for Backend

1. In your terminal on the EC2 instance, navigate to the backend directory of your cloned repository.

2. Create a Dockerfile for the backend application using a text editor:

    #Dockerfile
    # Example Dockerfile
    FROM node:14
    WORKDIR /usr/src/app
    COPY package*.json  ./
    RUN npm install
    COPY . .
    CMD ["node", "index.js"]
   

   

5.2 Build and Run the Docker Image

1. Build the Docker image for the backend:

    docker build -t threetier-backend:latest .
   

2. Run the Docker container for the backend:

    docker run -d -p 8080:8080 threetier-backend:latest
   

5.3 Push Backend Image to ECR

1. Follow similar steps as in Step 4.2 to create a new repository in Amazon ECR for the backend Docker image.

   

2. Push the backend Docker image to the newly created ECR repository.

   

   

Step 6: Set Up Kubernetes Cluster

6.1 Install kubectl and eksctl

1. Download and install kubectl on your EC2 instance:

    curl -o kubectl https://amazon-eks.s3.us-west-2.amazonaws.com/1.19.6/2021-01-05/bin/linux/amd64/kubectl
    chmod +x ./kubectl
    sudo mv ./kubectl /usr/local/bin
    kubectl version --short --client
   

   

2. Download and install eksctl on your EC2 instance:

    curl --silent --location "https://github.com/weaveworks/eksctl/releases/latest/download/eksctl_$(uname -s)_amd64.tar.gz" | tar xz -C /tmp
    sudo mv /tmp/eksctl /usr/local/bin
    eksctl version
   

   

6.2 Create EKS Cluster

1. Use eksctl to create an Amazon EKS cluster:

    eksctl create cluster --name three-tier-cluster --region us-east-1 --node-type t2.medium --nodes-min 2 --nodes-max 2
   

   This command will deploy a stack over AWS CloudFormation. Cluster creation may take around 15 to 20 minutes.

   

   This will create the Stack. As well as all the required resources such as two EC2 nodes, Elastic Kubernetes Service etc.

   

Step 7: Deploy Kubernetes Manifests

7.1 Create Namespace

1. Use kubectl to create a Kubernetes namespace for the application:

    kubectl create namespace workshop
   

   

7.2 Deploy Manifests

1. Apply the Kubernetes manifest files provided in the repository to deploy the application components:

    kubectl apply -f k8s_manifests/deploy.yaml
    kubectl apply -f k8s_manifests/secrets.yaml
    kubectl apply -f k8s_manifests/service.yaml
    kubectl apply -f k8s_manifests/backend-deployment.yaml
   

   

   

   

   

   

   

   

   

   Now, we have two tiers ready with us, i.e. mongodb and backend. We will run the following command to check it:

    kubectl get pods -n workshop
   

   

   Now, we will check the logs of backend pod again, as last time it wasn’t connecting to the database. And Boom!!! It is listening to port 8080.

    kubectl logs api-586c7b87fd-jslff -n workshop
   

   

   Now, we will work on frontend tier pod, and we will create deployment as well as service for the same.

   

   Now, we will check the pod count, with following command

    kubectl get pods -n workshop
   

Step 8: Install Application Load Balancer (ALB) Controller

if we need to do internal routing then we will use Ingress controller. We will install HELM package manager that will include the Kubernetes manifest files to create ingress controller.

We will now install Application Load Balancer (to access it from the internet) in EKS Cluster with the help of eksctl.

We need an account to perform the installation for that we will install the AWS IAM policy by running the command:

curl -O https://raw.githubusercontent.com/kubernetes-sigs/aws-load-balancer-controller/v2.5.4/docs/install/iam_policy.json
aws iam create-policy --policy-name AWSLoadBalancerControllerIAMPolicy --policy-document file://iam_policy.json
eksctl utils associate-iam-oidc-provider --region=us-west-2 --cluster=three-tier-cluster --approve
eksctl create iamserviceaccount --cluster=three-tier-cluster --namespace=kube-system --name=aws-load-balancer-controller --role-name AmazonEKSLoadBalancerControllerRole --attach-policy-arn=arn:aws:iam::626072240565:policy/AWSLoadBalancerControllerIAMPolicy --approve --region=us-west-2

We have successfully created the service account for Load Balancer.

8.1 Install Helm

1. Install Helm package manager on the EC2 instance:

    sudo snap install helm --classic
   

8.2 Install ALB Controller

1. Use Helm to install the AWS Load Balancer Controller for managing Application Load Balancers:

    helm repo add eks https://aws.github.io/eks-charts
    helm repo update
    helm install aws-load-balancer-controller eks/aws-load-balancer-controller -n kube-system -
   

   To see if my ALB is running or not, we will use the following command:

    kubectl get deployment -n kube-system aws-load-balancer-controller
   

   

Step 9: Deploy Ingress Controller for Internal Routing

9.1 Install Ingress Controller

1. Navigate to the /k8s_manifests/full_stack_lb.yaml file in your repository.

2. Use kubectl to create the Ingress controller:

    kubectl apply -f /path/to/full_stack_lb.yaml
   

   

Step 10: Map Domain

10.1 Map Domain to ALB En

dpoint

1. Suppose your domain is example.com. Navigate to your domain registrar's website (e.g., GoDaddy).

2. Access the DNS management section for your domain.

3. Create a new CNAME record with the following details:

   • Type: CNAME

   • Name: challenge (or any desired subdomain)

   • Value: <ALB DNS name> (e.g., k8s-workshop-mainlb-7f430e3450-1036210311.us-east-1.elb.amazonaws.com)

   • TTL: Custom, set to 600 seconds.

   •   Type: CNAME
       Name: challenge
       Value: k8s-workshop-mainlb-7f430e3450-1036210311.us-east-1.elb.amazonaws.com
       TTL: Custom >> 600 seconds.
     

     

Step 11: Verify Deployment

11.1 Check Load Balancers

1. Navigate to the AWS Management Console.

2. Go to EC2 > Load Balancers.

3. Search for the Load Balancer associated with your deployment (e.g., search for "challenge" or "k8s-workshop-mainlb").

11.2 Access the Application

1. Open a web browser and navigate to http://challenge.example.com (replace example.com with your domain).

2. Verify that you can access the deployed application successfully.

   

Step 12: Clean Up

12.1 Delete EKS Cluster

1. Delete the Amazon EKS cluster when you're done with the project:

    eksctl delete cluster --name three-tier-cluster --region ap-south-1
   

   

Happy deploying!