Kubernetes Cluster Setup on AWS EC2

Prerequisites

• AWS Account with appropriate permissions
• 3 EC2 instances running Ubuntu 18.04 or later
  • Master node: t3.medium (minimum 2 CPUs, 2GB RAM)
  • Worker nodes: t3.micro or larger (minimum 1 CPU, 1GB RAM)

Tip

For production workloads, consider using larger instance types and multiple master nodes for high availability.

Installation Steps

1. Update System Packages (All Nodes)

sudo apt-get update

2. Install Docker (All Nodes)

sudo apt-get install -y docker.io
sudo systemctl enable docker
sudo systemctl start docker

3. Install Kubernetes Tools (All Nodes)

curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add
sudo apt-add-repository "deb http://apt.kubernetes.io/ kubernetes-xenial main"
sudo apt-get update
sudo apt-get install -y kubeadm kubelet kubectl
sudo apt-mark hold kubeadm kubelet kubectl

Caution

The apt-mark hold command prevents accidental upgrades that could break your cluster.

4. Initialize Master Node

sudo kubeadm init --pod-network-cidr=10.244.0.0/16

Note

Save the kubeadm join command from the output - you’ll need it to add worker nodes.

5. Configure kubectl

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

6. Deploy Pod Network

kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

7. Join Worker Nodes

On each worker node, run the kubeadm join command from step 4:

sudo kubeadm join <master-ip>:6443 --token <token> --discovery-token-ca-cert-hash sha256:<hash>

Verification

Check cluster status:

kubectl get nodes
kubectl get pods --all-namespaces

All nodes should show Ready status and all system pods should be Running.