Inception of Things

This repository gathers three little projects using Vagrant, Kubernetes and more.

Table of Contents

1. Prerequisites
2. Part 1: Automate a simple k3s cluster with Vagrant
3. Part 2: K3s and Three Simple Applications
4. Part 3: K3d and Argo CD
5. Bonus: Integrating GitLab

Prerequisites

Before proceeding with the setup, ensure you have the following prerequisites on your host machine:

• Vagrant installed, and
• VirtualBox (or any other Vagrant provider) installed for virtualization capabilities.

Part 1: Automate a simple K3s cluster with Vagrant

The first project p1 involves automating a 2-machine cluster using k3s and vagrant.

K3s is a lightweight virtual machine-based Kubernetes distribution tool made for IoT and CI/CD environments.

Setting up the Virtual Machines

In part1, we define two boxes: a server and a worker.Vagrant helps us automate the creation and provisioning of multiple virtual machines from one configuration file: the Vagrantfile. Both boxes run the latest stable Ubuntu Operating System and run on 1 CPU and 1024 MB of RAM. Their hostnames and IP addresses are defined at the top of the file.

SERVER_IP = "192.168.56.110"
WORKER_IP = "192.168.56.111"
SERVER_NAME = "corozcoS"
WORKER_NAME = "corozcoSW"
TOKEN_FILE = "/vagrant/node-token"

Vagrant.configure("2") do |config|

  config.vm.box = "ubuntu/focal64"
  config.vm.provider "virtualbox" do |vb|
    vb.memory = 1024
    vb.cpus = 1
  end

  config.vm.define "#{SERVER_NAME}" do |control|
    control.vm.hostname = "#{SERVER_NAME}"
    control.vm.network "private_network", bridge: "enp0s8", ip: "#{SERVER_IP}"
  end

  config.vm.define "#{WORKER_NAME}" do |control|
    control.vm.hostname = "#{WORKER_NAME}"
    control.vm.network "private_network", bridge: "enp0s8", ip: "#{WORKER_IP}"
  end
end

Deploying the k3s cluster

Once our machines are up and running, we can configure the k3s cluster.

Server node

# Initialize a new cluster using etcd specifying the node's advertising address 
# Copy the node-token to the host machine
$serverscript = <<-SCRIPT
apt-get update
curl -sfL https://get.k3s.io | INSTALL_K3S_EXEC="--cluster-init --node-ip #{SERVER_IP}" sh -
cp /var/lib/rancher/k3s/server/node-token /vagrant
SCRIPT

# We run this script on the server machine
control.vm.provision "shell", inline: $serverscript

# Initialize a new cluster using etcd specifying the node's advertising address 
# Copy the node-token to the host machine
$serverscript = <<-SCRIPT
apt-get update
curl -sfL https://get.k3s.io | INSTALL_K3S_EXEC="--cluster-init --node-ip #{SERVER_IP}" sh -
cp /var/lib/rancher/k3s/server/node-token /vagrant
SCRIPT

# We run this script on the node server
control.vm.provision "shell", inline: $nodescript

Part 2: K3s and Three Simple Applications

We set up a single virtual machine with K3s in server mode and deploy three web applications.

Configuration

A single virtual.

K3s is installed in server mode.

Three web applications are deployed that run in your K3s instance.

The applications should be accessible via specific hostnames configured to respond to requests sent to IP address 192.168.56.110.

Applications

• app1: Accessible when using HOST app1.com
• app2: Accessible when using HOST app2.com (with three replicas)
• app3: Selected by default for any other HOST.

Ingress Configuration

An Ingress resource is configured to manage routing based on the hostname of incoming requests.

Part 3: K3d and Argo CD

Setting up K3d and implementing a continuous integration workflow using Argo CD.

Configuration Steps

• Install K3d (which requires Docker) on a virtual machine without using Vagrant.
• Create two namespaces:
  • One dedicated to Argo CD.
  • Another named dev for containing an application.
• Configure Argo CD to automatically deploy an application from a public GitHub repository.

Application Deployment

• The application should have two different versions (v1 and v2).
• The application is deployed in the dev namespace.
• Demonstrate updating the application by changing its version in the GitHub repository.

Argo CD Integration

• Set up Argo CD to monitor your GitHub repository and apply changes automatically.
• Show how Argo CD synchronizes and updates the application when changes are made in GitHub.

Bonus: Integrating GitLab

The bonus section aims to enhance the project by adding GitLab to your setup from Part 3.

Requirements:

• Install GitLab locally within your Kubernetes cluster.

• Ensure that all functionalities implemented in Part 3 work seamlessly with your local GitLab instance.

Steps:

• Use Helm or any other tools necessary for installing GitLab.

• Configure GitLab to integrate with your Kubernetes cluster properly.

• Ensure that CI/CD pipelines can trigger deployments based on changes made in your GitLab repositories.