Install Kubernetes with Docker on AWS

Overview

This lab walks through using kubeadm to install Kubernetes with Docker as the container runtime.

Following commands must be run as the root user. To become root run:

sudo su -

Install packages required for Kubernetes on all servers as the root user

curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | apt-key add -

Create Kubernetes repository by running the following as one command.

echo "deb https://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee -a /etc/apt/sources.list.d/kubernetes.list

Now that you’ve added the repository install the packages

apt-get update
apt-get install -y kubelet=1.21.0-00 kubeadm=1.21.0-00 kubectl

The kubelet is now restarting every few seconds, as it waits in a crashloop for kubeadm to tell it what to do.

Run the following commands only on the master node. Initialize the master node

kubeadm init --kubernetes-version=1.21.0 --ignore-preflight-errors=all

If everything was successful output will contain

Your Kubernetes master has initialized successfully!

Note the kubeadm join... command, it will be needed later on.

Exit to ubuntu user

exit

Now configure server so you can interact with Kubernetes as the unprivileged user.

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

Run following on the master to enable IP forwarding to IPTables.

sudo sysctl net.bridge.bridge-nf-call-iptables=1

Install a Pod network on the master node

kubectl apply -f "https://cloud.weave.works/k8s/net?k8s-version=$(kubectl version | base64 | tr -d '\n')"

Wait until coredns pod is in a running state

kubectl get pods -n kube-system

Log into each of the worker nodes and run the join command from kubeadm init master output.

kubeadm join <command from kubeadm init output>

To confirm nodes have joined successfully log back into master and run

kubectl get nodes -w

When they are in a Ready state the cluster is online and nodes have been joined.

To stop watching type ctrl+c