Create 3 nodes Kubernetes cluster locally with Vagrant

README.md

3 Virtual Machines Kubernetes cluster

Dependencies

You should install VirtualBox and Vagrant before you start.

Creating the cluster

You should create a Vagrantfile in an empty directory with the following content:

Vagrant.configure("2") do |config|
  config.vm.provider :virtualbox do |v|
    v.memory = 1024
    v.cpus = 1
  end

  config.vm.provision :shell, privileged: true, inline: $install_common_tools

  config.vm.define :master do |master|
    master.vm.box = "ubuntu/xenial64"
    master.vm.hostname = "master"
    master.vm.network :private_network, ip: "10.0.0.10"
    master.vm.provision :shell, privileged: false, inline: $provision_master_node
  end

  %w{worker1 worker2}.each_with_index do |name, i|
    config.vm.define name do |worker|
      worker.vm.box = "ubuntu/xenial64"
      worker.vm.hostname = name
      worker.vm.network :private_network, ip: "10.0.0.#{i + 11}"
      worker.vm.provision :shell, privileged: false, inline: <<-SHELL
sudo /vagrant/join.sh
echo 'Environment="KUBELET_EXTRA_ARGS=--node-ip=10.0.0.#{i + 11}"' | sudo tee -a /etc/systemd/system/kubelet.service.d/10-kubeadm.conf
sudo systemctl daemon-reload
sudo systemctl restart kubelet
SHELL
    end
  end

  config.vm.provision "shell", inline: $install_multicast
end


$install_common_tools = <<-SCRIPT
# bridged traffic to iptables is enabled for kube-router.
cat >> /etc/ufw/sysctl.conf <<EOF
net/bridge/bridge-nf-call-ip6tables = 1
net/bridge/bridge-nf-call-iptables = 1
net/bridge/bridge-nf-call-arptables = 1
EOF

# disable swap
swapoff -a
sed -i '/swap/d' /etc/fstab

# Install kubeadm, kubectl and kubelet
export DEBIAN_FRONTEND=noninteractive
apt-get -qq install ebtables ethtool
apt-get -qq update
apt-get -qq install -y docker.io apt-transport-https curl
curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | apt-key add -
cat <<EOF >/etc/apt/sources.list.d/kubernetes.list
deb http://apt.kubernetes.io/ kubernetes-xenial main
EOF
apt-get -qq update
apt-get -qq install -y kubelet kubeadm kubectl
SCRIPT

$provision_master_node = <<-SHELL
OUTPUT_FILE=/vagrant/join.sh
rm -rf $OUTPUT_FILE

# Start cluster
sudo kubeadm init --apiserver-advertise-address=10.0.0.10 --pod-network-cidr=10.244.0.0/16 | grep "kubeadm join" > ${OUTPUT_FILE}
chmod +x $OUTPUT_FILE

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

# Fix kubelet IP
echo 'Environment="KUBELET_EXTRA_ARGS=--node-ip=10.0.0.10"' | sudo tee -a /etc/systemd/system/kubelet.service.d/10-kubeadm.conf

# Configure flannel
curl -o kube-flannel.yml https://raw.githubusercontent.com/coreos/flannel/v0.9.1/Documentation/kube-flannel.yml
sed -i.bak 's|"/opt/bin/flanneld",|"/opt/bin/flanneld", "--iface=enp0s8",|' kube-flannel.yml
kubectl create -f kube-flannel.yml

sudo systemctl daemon-reload
sudo systemctl restart kubelet
SHELL

$install_multicast = <<-SHELL
apt-get -qq install -y avahi-daemon libnss-mdns
SHELL

Starting the cluster

You can create the cluster with:

$ vagrant up

Clean up

You can delete the cluster with:

$ vagrant destroy -f

@nambyats

what is the username password of this vmbox

you can use vagrant ssh to enter to the virtual machine:

vagrant ssh master
vagrant ssh worker1
vagrant ssh worker2

It is not working in the current state.

Changes needed:

1. memory to 2048
2. cpu to 2
3. kube-flannel version from 0.9.0 to master inside the url
4. append flag --discovery-token-unsafe-skip-ca-verification after creating join.sh script

how to login to the cluster, pl share instructions

vagrant@master:$ kubectl get nodes
The connection to the server
localhost:8080 was refused - did you specify the right host or port?
vagrant@master:$

the api-container and other kubernetes containers didnt start automatically after dployment

Due to difference in cgroup being used in docker and kubeadm, kubeadm init fails. Since kubeadm uses systemd cgroup by default, so the same should be configured for docker. Solution is documented in kubernetes.io "https://kubernetes.io/docs/setup/production-environment/container-runtimes/#docker"

I modified "install_common_tools" like below, which worked for me:

$install_common_tools = <<-SCRIPT
# bridged traffic to iptables is enabled for kube-router.
cat >> /etc/ufw/sysctl.conf <<EOF
net/bridge/bridge-nf-call-ip6tables = 1
net/bridge/bridge-nf-call-iptables = 1
net/bridge/bridge-nf-call-arptables = 1
EOF

# disable swap
swapoff -a
sed -i '/swap/d' /etc/fstab

# Install kubeadm, kubectl and kubelet
export DEBIAN_FRONTEND=noninteractive
apt-get -qq install ebtables ethtool
apt-get -qq update
apt-get -qq install -y docker.io apt-transport-https curl
curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | apt-key add -
cat <<EOF >/etc/apt/sources.list.d/kubernetes.list
deb http://apt.kubernetes.io/ kubernetes-xenial main
EOF
apt-get -qq update
apt-get -qq install -y kubelet kubeadm kubectl
# included for mismatch in cgroup between docker and kubelet
sudo mkdir /etc/docker
cat <<EOF | sudo tee /etc/docker/daemon.json
{
  "exec-opts": ["native.cgroupdriver=systemd"],
  "log-driver": "json-file",
  "log-opts": {
    "max-size": "100m"
  },
  "storage-driver": "overlay2"
}
EOF
sudo systemctl daemon-reload
sudo systemctl restart docker
SCRIPT

Facing an error while trying to locally set up and practice kubernetes concepts.
Also tried using https://github.com/mmumshad/kubernetes-the-hard-way/blob/master/vagrant/Vagrantfile, still got the same error.
Kindly guide me in the right direction, I'm not sure what's the problem, and have tried changing vagrant and virtual box versions but still not working.
Btw, basic Vagrant files like one generated from vagrant init hashicorp/bionic64 are working fine.

Error I'm getting:

==> master: Importing base box 'ubuntu/xenial64'...
==> master: Matching MAC address for NAT networking...
==> master: Checking if box 'ubuntu/xenial64' version '20211001.0.0' is up to date...
==> master: Setting the name of the VM: testVagrant_master_1640650019434_42678
==> master: Clearing any previously set network interfaces...
The IP address configured for the host-only network is not within the
allowed ranges. Please update the address used to be within the allowed
ranges and run the command again.

  Address: 10.0.0.10
  Ranges:

Valid ranges can be modified in the /etc/vbox/networks.conf file. For
more information including valid format see:

  https://www.virtualbox.org/manual/ch06.html#network_hostonly

@danielepolencic How to use this to spin up with latest kubernetes version with ubuntu 22.04 ?