Launching an EKS Cluster and Deploying a High-Availability Nginx Application

Prerequisites

- An "AWS account": To provision cloud resources.

- Basic "CLI familiarity": Required for interacting with AWS and Kubernetes.

Step 1: Create an IAM User with Admin Permissions

Actions:

1. Create a new user name "eks-user" with the "AdministratorAccess" policy.

-Select ‘attach policies directly and check "AdministratorAccess" policy

2. Generate an "Access Key" under Security credentials.

Select CLI in ‘use case’

Download the Access key and secret access key or save it in a note pad

Why This Matters:

- Security: Avoid using your AWS root account for daily tasks; IAM users minimize risk.

- Least Privilege: While "AdministratorAccess" is used here for simplicity, restrict permissions further in production.

- Auditability: Dedicated users make it easier to track actions in your AWS environment.

Step 2: Launch an EC2 Instance & Configure CLI Tools

Actions:

1. Launch a "t2.micro" instance with "Amazon Linux 2" and a key pair.

-In the Key pair (login) box, select Create new key pair. Give it a Key pair name .

-Click Create new key pair. This will download the key pair for later use.

-Expand Network settings and click on Edit In the Network settings box:

- Network: Leave as default. Subnet: Leave as default. Auto-assign Public IP: Select Enable.

• Once the instance is fully created, check the checkbox next to it and click Connect at the top of the window.

• In the Connect to your instance dialog, select EC2 Instance Connect (browser-based SSH connection). Click Connect

2. Install/update "AWS CLI v2", "kubectl", and "eksctl".

Run “aws --version “ It should be an older version.

Download v2: curl "https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip" -o "awscliv2.zip"

-To unzip the file, run unzip awscliv2.zip

- See where the current AWS CLI is installed:

-Run ‘which aws’ It should be /usr/bin/aws.

Update it:

sudo ./aws/install --bin-dir /usr/bin --install-dir /usr/bin/aws-cli --update

• Check the version of AWS CLI: aws --version

It should now be updated.

• Configure the CLI:

- For AWS Access Key ID: paste in the access key ID you copied earlier.

- For AWS Secret Access Key, paste in the secret access key you copied earlier.

- For Default region name, enter your region e.g us-east-1.

- For Default output format, enter json.

-Download kubectl:- curl -o kubectl https://amazon-eks.s3.us-west-2.amazonaws.com/1.16.8/2020-04-16/ bin/linux/amd64/kubectl

- Apply execute permissions to the binary: chmod +x ./kubectl

-Copy the binary to a directory in your path: mkdir -p $HOME/bin && cp ./kubectl $HOME/bin/kubectl && export PATH=$PATH:$HOME/bin

To ensure kubectl is installed: kubectl version --short --client

-Download eksctl: curl --silent --location "https://github.com/weaveworks/eksctl/releases/latest/download/e ksctl_$(uname -s)_amd64.tar.gz" | tar xz -C /tmp

-Move the extracted binary to /usr/bin: sudo mv /tmp/eksctl /usr/bin

Get the version of eksctl: eksctl version

Why This Matters:

- Consistency: Using an EC2 instance as a "management node" ensures a clean CLI environment.

- Tooling:

• "AWS CLI": Authenticates and interacts with AWS services.

• "kubectl": Manages Kubernetes clusters.

• "eksctl": Simplifies EKS cluster creation (e.g., auto-generates VPCs and node groups).

- Cost Optimization: The "t2.micro" instance is free-tier eligible and sufficient for CLI tasks.

Step 3: Provision an EKS Cluster

Actions:

1. Run the command "eksctl create cluster" with "t3.medium" worker nodes.

Provision an EKS cluster with three worker nodes in your region e.g eu-north-1

eksctl create cluster --name dev --region eu-north-1--nodegroup-name standard-workers --node-type t3.medium --nodes 3 --nodes-min 1 --nodes-max 4 --managed

Note

If your EKS resources can't be deployed due to AWS capacity issues, delete your eksctl-dev-cluster CloudFormation stack and retry the command using the --zones parameter and suggested availability zones from the CREATE_FAILED message:

Noted

It will take 10–15 minutes since it's provisioning the control plane and worker nodes, attaching the worker nodes to the control plane, and creating the VPC, security group, and Auto Scaling group.

● In the AWS Management Console, navigate to CloudFormation and take a look at what’s going on there. Select the eksctl-dev-cluster stack (this is our control plane). Click Events, so you can see all the resources that are being created.

● We should then see another new stack being created — this one is our node group.

Once both stacks are complete, navigate to Elastic Kubernetes Service > Clusters. Click the listed cluster.

● If you see a Your current user or role does not have access to Kubernetes objects on this EKS cluster message just ignore it, as it won't impact the next steps of the activity.

● Click the Compute tab (under Configuration), and then click the listed node group. There, we'll see the Kubernetes version, instance type, status, etc. Click dev in the breadcrumb navigation link at the top of the screen.

● Click the Networking tab (under Configuration), where we'll see the VPC, subnets, etc. Click the Logging tab (under Configuration), where we'll see the control plane logging info.

Note

The control plane is abstracted — we can only interact with it using the command line utilities or the console. It’s not an EC2 instance we can log into and start running Linux commands on.

Navigate to EC2 > Instances, where you should see the instances have been launched. Close out of the existing CLI window, if you still have it open.

Select the original t2.micro instance, and click Connect at the top of the window.

-In the Connect to your instance dialog, select EC2 Instance Connect (browser-based SSH connection). Click Connect.

-In the CLI, check the cluster: eksctl get cluster

Enable it to connect to our cluster: aws eks update-kubeconfig --name dev --region eu-north-1

Why This Matters:

- Managed Control Plane: AWS handles Kubernetes control plane updates and scaling.

- High Availability:

• The flags "--nodes 3 --nodes-min 1 --nodes-max 4" enable auto-scaling for workload resilience.

• "--zones" spreads nodes across availability zones to prevent downtime during failures.

- Cost Control: "t3.medium" balances performance and cost for testing.

Step 4: Deploy an Nginx Application from A Git Repository

Actions:

1. Install Git:

sudo yum install -y git

Download the course files: git clone https://github.com/ACloudGuru-Resources/Course_EKS-Basics

Change directory: cd Course_EKS-Basics

2. Apply the "nginx-svc.yaml" (LoadBalancer) and "nginx-deployment.yaml" manifests.

Take a look at the deployment file: cat nginx-deployment.yaml

Take a look at the service file: cat nginx-svc.yaml

-Create the service: kubectl apply -f ./nginx-svc.yaml

- Check its status: kubectl get service

Copy the external DNS hostname of the load balancer, and paste it into a text file, as we'll need it in a minute.

- Create the deployment:

kubectl apply -f ./nginx-deployment.yaml

-Check its status: kubectl get deployment

-View the pods: kubectl get pod

-View the ReplicaSets: kubectl get rs

Access the application using the load balancer, replacing with the IP you copied earlier (it might take a couple of minutes to update): curl “DNS name”

The output should be the HTML for a default Nginx web page. ● In a new browser tab, navigate to the same IP, where we should then see the same Nginx web page.

Why This Matters:

- LoadBalancer Service: Exposes your app via an AWS-managed Elastic Load Balancer (ELB).

- Deployment: Replicates pods across nodes; Kubernetes self-heals if pods/nodes fail.

- Validation: Use "curl" to confirm your app is reachable.

Step 5: Test High Availability

Actions:

1. Stop a worker node via the EC2 console.

2. Monitor Kubernetes rescheduling pods to healthy nodes.

Why This Matters:

- Resilience: EKS automatically replaces failed nodes/pods, minimizing downtime.

- Real-World Proof: Simulating failures validates your cluster’s outage-handling capability.

Conclusion

In the CLI, delete everything: eksctl delete cluster dev --region eu-north-1