Step 1: Update Your System
Update the package list and upgrade installed packages:
sudo apt update && sudo apt upgrade -y
sudo reboot
Step 2: Install Dependencies
Install required tools and packages:
sudo apt install -y apt-transport-https ca-certificates curl gnupg lsb-release
Step 3: Disable Swap
Kubernetes requires swap to be disabled:
sudo swapoff -a
sudo sed -i '/ swap / s/^/#/' /etc/fstab
Step 4: Install Docker or containerd
Kubernetes needs a container runtime. We'll use containerd (recommended).
4.1: Install containerd
sudo apt install -y containerd
4.2: Configure containerd
Generate the default configuration file:
sudo mkdir -p /etc/containerd
sudo containerd config default | sudo tee /etc/containerd/config.toml
Restart containerd:
sudo systemctl restart containerd
sudo systemctl enable containerd
Step 5: Install Kubernetes Components
Install kubeadm, kubelet, and kubectl.
5.1: Add the Kubernetes APT repository
curl -fsSL https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -
echo "deb https://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee /etc/apt/sources.list.d/kubernetes.list
sudo apt update
5.2: Install kubeadm, kubelet, and kubectl
sudo apt install -y kubelet kubeadm kubectl
sudo apt-mark hold kubelet kubeadm kubectl
Step 6: Initialize the Kubernetes Cluster
Run the following command on the master node:
sudo kubeadm init --pod-network-cidr=192.168.0.0/16
6.1: Configure kubectl 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
6.2: Save the Join Command
The output of kubeadm init will include a kubeadm join command for worker nodes. Save this for later.
Step 7: Install a Pod Network Add-On
Choose a CNI (Container Network Interface). We'll use Calico.
7.1: Apply the Calico manifest
kubectl apply -f https://docs.projectcalico.org/manifests/calico.yaml
Step 8: Add Worker Nodes
Run the kubeadm join command from Step 6.2 on each worker node:
sudo kubeadm join <master-ip>:6443 --token <token> \
--discovery-token-ca-cert-hash sha256:<hash>
Step 9: Verify the Cluster
9.1: Check Nodes
On the master node, check the status of nodes:
kubectl get nodes
9.2: Check Pods
Verify that the cluster is working by checking pods in the kube-system namespace:
kubectl get pods -n kube-system
Optional: Enable Autocompletion for kubectl
sudo apt install -y bash-completion
echo 'source <(kubectl completion bash)' >>~/.bashrc
source ~/.bashrc
Troubleshooting Tips
-
Reset the Cluster
If the installation fails, reset kubeadm and try again:sudo kubeadm reset -f sudo rm -rf $HOME/.kube -
Check Logs
Use the following commands to troubleshoot issues:journalctl -xeu kubelet kubectl describe pod <pod-name> -n kube-system
This guide provides a basic Kubernetes cluster installation. For production, consider high-availability setups, security configurations, and monitoring tools. Let me know if you'd like additional details!