Create single node kubernetes cluster with kubeadm using vagrant and ubuntu

Vagrantfile

$script = <<-SCRIPT
#!/bin/sh
set -ex

apt-get update && apt-get install -y apt-transport-https
curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | apt-key add -
echo "deb http://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee > /etc/apt/sources.list.d/kubernetes.list
apt-get update && apt-get install -y docker.io kubeadm
swapoff -a
sudo sed -i.bak '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab
systemctl enable docker.service

sudo kubeadm config images pull
IP_ADDRESS=`ifconfig eth1 | grep 'inet ' | awk '{print $2}'`
sudo kubeadm init --apiserver-cert-extra-sans=$IP_ADDRESS --node-name=`hostname`

# configure kubectl
mkdir -p /home/vagrant/.kube
sudo cp -i /etc/kubernetes/admin.conf /home/vagrant/.kube/config
sudo chown $(id -u):$(id -g) /home/vagrant/.kube/config

# allow pods to run on this master node
kubectl taint nodes --all node-role.kubernetes.io/master-

# install network plugin
kubectl apply -f https://docs.projectcalico.org/v3.1/getting-started/kubernetes/installation/hosted/kubeadm/1.7/calico.yaml

# install dashboard
kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml

grep 'client-certificate-data' ~/.kube/config | awk '{print $2}' | base64 -d >> kubecfg.crt
grep 'client-key-data' ~/.kube/config | awk '{print $2}' | base64 -d >> kubecfg.key
#openssl pkcs12 -export -clcerts -inkey kubecfg.key -in kubecfg.crt -out kubecfg.p12 -name "kubernetes-client"

# create service account
cat <<EOF | kubectl create -f -
apiVersion: v1
kind: ServiceAccount
metadata:
  name: admin-user
  namespace: kube-system
EOF

# create ClusterRoleBinding
cat <<EOF | kubectl create -f -
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: admin-user
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: admin-user
  namespace: kube-system
EOF

echo Dashboard bearer token:
kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | grep admin-user | awk '{print $1}')
SCRIPT

Vagrant.configure("2") do |config|
    config.vm.provider "virtualbox" do |v|
        v.name = "k8s"
        v.cpus = 4
        v.memory = 6144
    end

    config.vm.box = "bento/ubuntu-18.04"
    config.vm.hostname = "k8s"
    config.vm.network :private_network, ip: "192.168.66.100"
    config.vm.provision "shell", inline: $script
end