Deploy Kubernetes Cluster on Workstation Using VirtualBox

Overview

This page describes how to create a minimal on-premises Kubernetes cluster on a workstation using VirtualBox.

Objectives

1. Create virtual machines with Kublr
2. Create a Kubernetes cluster

Prerequisites

• VirtualBox installed
• Vagrant installed
• 10.5 GiB free RAM
• 30 GB free disk space

Create virtual machines

You will need to to create 3 virtual machines:

• a VM for Kublr with Ubuntu Server 18.04, 1.5 GiB RAM and 10 GB disk space
• a VM for the master node with Ubuntu Server 18.04, 5 GiB RAM and 10 GB disk space
• a VM for the worker node with Ubuntu Server 18.04, 4 GiB RAM and 10 GB disk space

Additional requirements:

• The master and worker nodes should be accessible from the Kublr VM via SSH with sudo with no password
• The Kublr VM should expose port 9080 to the host to make the Kublr UI accessible to the administrator

Create a directory and go there:

mkdir my-cluster
cd my-cluster
touch Vagrantfile

Edit Vagrantfile via your favorite IDE or editor. Here is example content:

KUBLR_IP = "172.28.128.10"
MASTER_IP = "172.28.128.11"
WORKER_IP = "172.28.128.12"
 
MASTER_MEMORY_MB = "5120" #5G
WORKER_MEMORY_MB = "4096" #4G
 
Vagrant.configure("2") do |config|
  config.vm.box = "ubuntu/bionic64"
  config.vm.define "kublr" do |kublr|
    kublr.vm.network "private_network", ip: KUBLR_IP
    kublr.vm.provider "virtualbox" do |vb|
        vb.memory = 1536 #1.5G
      end
    kublr.vm.provision "docker" do |d|
      d.run "kublr", # --name kublr
            image: "kublr/kublr:1.22.2",
            daemonize: true, #-d
            restart: "unless-stopped", # --restart=unless-stopped
            args: "-p 9080:9080"
    end
    kublr.vm.provision "shell", inline: "docker exec -i kublr /bin/bash -c 'echo \"KUBLR_HOST=#{KUBLR_IP}:9080\" > /ip.external'; docker restart kublr"
  end
  config.vm.define "master" do |master|
    master.vm.network "private_network", ip: MASTER_IP
    master.vm.provider "virtualbox" do |vb|
      vb.memory = MASTER_MEMORY_MB
    end
  end
  config.vm.define "worker" do |worker|
    worker.vm.network "private_network", ip: WORKER_IP
    worker.vm.provider "virtualbox" do |vb|
      vb.memory = WORKER_MEMORY_MB
    end
  end
end

Pay attention to VM IPs:

KUBLR_IP = "172.28.128.10"
MASTER_IP = "172.28.128.11"
WORKER_IP = "172.28.128.12"

Make sure that they belong to a private address space, but not to an existing local network. Vagrant will create a corresponding private network.

Bring up the infrastructure:

vagrant up

It takes a few minutes to create the VMs and install Kublr

Kublr UI will be available at http://172.28.128.10:9080 (with login / password admin / kublrbox)

Add SSH keys

Go to the Credentials tab and add the SSH private key for the master VM The key itself is stored in .vagrant/machines/master/virtualbox/private_key

Add the key for the worker VM It is stored in .vagrant/machines/worker/virtualbox/private_key

Create Cluster

1. Click on Cluster Menu in Left Navigation Menu Bar

2. Click on Add Cluster

3. Enter Cluster Name.

4. Select Provider: Bring Your own Infrastructure

5. Click the INSTANCES step.

6. Use the Master Configuration section.

7. Enter master parameters:

   • User Name: vagrant
   • SSH Key Name: the private SSH key for the master VM added before
   • IP/DNS of Master 1: IP of the master VM specified in Vagrantfile

8. Scroll to the Instance Group section (default name group1).

9. Specify the parameters of the worker node(s) in your group as described below:

   • User Name: vagrant
   • SSH Key Name: the private SSH key for the worker VM added before
   • Add IP/DNS Addresses: IP of the worker VM specified in Vagrantfile

10. Click the SETUP FEATURES step.

11. Leave the following options disabled: Ingress Controller, Self-Hosted Logging, Self-Hosted Monitoring

12. Click the REVIEW AND CREATE step.

13. Review the summary and click CONFIRM AND INSTALL button.

    In a few minutes the cluster will be created.