1. Prerequisites

2. Virtual Machines

  • use this gist to create the virtual machines
  • during installation use the name k8s-master on the first machine and k8s-node0x on the nodes
  • install OpenSSH Server package
  • reboot
  • call sudo nmap -sP 192.168.1.0/24 on your host to get the ip address of the newly created VM:
Nmap scan report for 192.168.1.208
Host is up (0.00024s latency).
MAC Address: 52:54:00:A4:6B:0B (QEMU virtual NIC)

3. Post-Install

ssh into the VM

packages

  • sudo apt update && sudo apt upgrade
  • sudo apt install curl git gnupg vim # and other packages you want

swap

  • sudo swapoff -a
  • sudo sed -i '/ swap / s/^/#/' /etc/fstab

static ip configuration

edit /etc/netplan/01-netcfg.yaml:

# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
  version: 2
  renderer: networkd
  ethernets:
    enp1s0:
      dhcp4: no
      addresses: [192.168.1.201/24]
      gateway4: 192.168.1.1
      nameservers:
        addresses: [192.168.1.1,8.8.8.8]

sudo netplan apply

4. Hostnames and IPs

copy to your /etc/hosts on the host machine

192.168.1.201   k8s-master
192.168.1.211   k8s-node01
192.168.1.212   k8s-node02
192.168.1.213   k8s-node03

5. SSH

Keys

ssh-keygen -t rsa ssh-copy-id <user>@k8s-master and on other nodes

Config

Host k8s-master
        Hostname k8s-master
        IdentityFile /home/ibay/.ssh/id_rsa_k8s
Host k8s-node01
        Hostname k8s-node01
        IdentityFile /home/ibay/.ssh/id_rsa_k8s
Host k8s-node02
        Hostname k8s-node02
        IdentityFile /home/ibay/.ssh/id_rsa_k8s
Host k8s-node03
        Hostname k8s-node03
        IdentityFile /home/ibay/.ssh/id_rsa_k8s

chmod 600 ~/.ssh/config

6. Install the components

on each VM

  • sudo apt update && sudo apt upgrade
  • sudo apt install -qy apt-transport-https software-properties-common
  • curl -s https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
  • sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu bionic stable"
  • sudo apt update && sudo apt install -qy docker-ce
  • curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -
  • echo "deb http://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee -a /etc/apt/sources.list.d/kubernetes.list
  • sudo apt update && sudo apt install -y kubeadm kubelet kubectl
  • sudo systemctl enable docker
  • sudo systemctl start docker

7. Init k8s master

sudo kubeadm init

copy the output with the token. It will be needed to join the workers:

kubeadm join 192.168.1.201:6443 --token v15nn2.efdd86ctvv2py4sj -- \
discovery-token-ca-cert-hash sha256:1501b51b6052216b206a5f065b50617a3f5bbca57f3b40d60314c04a27e4f7e7

mkdir -p $HOME/.kube

sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config

sudo chown $(id -u):$(id -g) $HOME/.kube/config

install networking

on master install one of the kubernetes network solutions, e.g. Weave Net

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

8. Join the workers to the cluster

kubeadm join 192.168.1.201:6443 --token v15nn2.efdd86ctvv2py4sj \
--discovery-token-ca-cert-hash sha256:1501b51b6052216b206a5f065b50617a3f5bbca57f3b40d60314c04a27e4f7e7

9. Test your cluster

  • copy the kube config to your host: scp k8s-master:/home/ibay/.kube/config ~/.kube
  • check your cluster: kubectl get nodes

deploy hello-kubernetes with replication 3 or the amount of your nodes

curl -L https://raw.githubusercontent.com/paulbouwer/hello-kubernetes/master/yaml/hello-kubernetes.yaml \
  | sed 's/replicas: .*/replicas: 3/' \
  | kubectl apply -f -