Docker installation

First, let's install updates, dependencies and docker:

sudo apt update
sudo apt upgrade
sudo apt install apt-transport-https # already installed
sudo apt install docker.io

Now, we can start docker and enable it to start during the system boot:

sudo systemctl start docker
sudo systemctl enable docker

Kubernetes installation

Before the installation, we need to add the key:

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

To create the apt repository for Kubernetes, we open a file:

sudo nano /etc/apt/sources.list.d/kubernetes.list

and add the following line into it and close the file:

deb http://apt.kubernetes.io/ kubernetes-xenial main

Time to update and install kebernetes:

sudo apt update
sudo apt install kubelet kubeadm kubectl kubernetes-cni

Kubernetes master

To initialise Kubernetes cluster to run as master, execute the below command:

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

If you receive this error:

[preflight] Some fatal errors occurred:
[ERROR Swap]: running with swap on is not supported. Please disable swap
[preflight] If you know what you are doing, you can make a check non-fatal with `--ignore-preflight-errors=...`

You will need to disable the swap:

sudo nano /etc/fstab # comment swap to disable permanently
sudo swapoff -a

After the initialisation, you will see something like this:

Your Kubernetes master has initialized successfully!

To start using your cluster, you need to run the following as a regular user:

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

You should now deploy a pod network to the cluster.

Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
	https://kubernetes.io/docs/concepts/cluster-administration/addons/

You can now join any number of machines by running the following on each node
as root:

kubeadm join 10.143.6.161:6443 --token de5fen.6y2w4x7shlyhnfyf8 --discovery-token-ca-cert-hash sha256:2a9dfacf654eba7d374b8dfac0028d6a094c550c67bc084f1efcc1f4301ca656

To complete the setup:

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

Execute below commands on master node to apply network settings:

sudo kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
sudo kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/k8s-manifests/kube-flannel-rbac.yml

Now, check all pods:

sudo kubectl get pods --all-namespaces

Kubernetes node

First of all, follow: Docker installation and Kubernetes installation. Then:

kubeadm join 10.143.6.161:6443 --token de5fen.6y2w4x7shlyhnfyf8 --discovery-token-ca-cert-hash sha256:2a9dfacf654eba7d374b8dfac0028d6a094c550c67bc084f1efcc1f4301ca656

Go back to Master and check:

kubectl get nodes

NAME STATUS ROLES AGE VERSION
k8-master Ready master 17h v1.11.0
k8-node1 Ready  37s v1.11.0
k8-node2 Ready  29s v1.11.0