Talk and workshop presented at JConf Dominicana — July 2024

What is IaC?

Infrastructure as Code (IaC) is a fundamental practice in DevOps and modern system administration. It involves managing and provisioning infrastructure through human-readable configuration files, rather than through manual processes or graphical interfaces.

Key Benefits:

  • Code Versioning: Store your infrastructure in Git.
  • Replicability: Create identical environments (Dev, QA, Prod) consistently.
  • Speed: Deploy servers and networks in seconds.
  • Cost Reduction: Avoid human errors and forgotten/zombie resources.

Why “for everyone”?

IaC is often thought to be exclusively for large cloud architectures. However, automation principles are useful at any scale: from setting up a personal server to deploying complex clusters. If you have to install, configure, or back up something more than once, you should be using IaC.

The Workshop: From Manual to Automated

In this workshop, we went through the evolution of infrastructure across 7 practical modules, using DigitalOcean as our cloud provider.

Base Requirements:

  • DigitalOcean Account.
  • Java 21.
  • Maven.
  • Docker.

Module 1: The Manual Way (Control Panel)

We started by exploring how to create a Droplet (server) the traditional way, manually choosing the region, image (Debian 12), and size to understand what we would automate later.

Module 2: CLI Automation with doctl

The first step towards automation is using the command line. doctl is the official DigitalOcean client that allows interaction with their API.

doctl compute droplet create \
  --image debian-12-x64 \
  --size s-1vcpu-512mb-10gb \
  --region nyc1 \
  --enable-monitoring \
  iac-everyone-server-1

Module 3: Declarative Infrastructure with OpenTofu

OpenTofu (the open-source fork of Terraform) allows us to define resources declaratively in .tf files.

resource "digitalocean_droplet" "iac-everyone-server-1" {
  image  = "debian-12-x64"
  name   = "iac-everyone-server-1"
  region = "nyc1"
  size   = "s-1vcpu-512mb-10gb"
  ssh_keys = [
    data.digitalocean_ssh_key.my_key.id
  ]
}

Module 4: IaC with Programming Languages (Pulumi)

Pulumi allows managing infrastructure using conventional languages like Java, JavaScript, or Python, making it easier to integrate with business logic and unit testing.

Pulumi.run(ctx -> {
    var web = new Droplet("web", DropletArgs.builder()
        .image("debian-12-x64")
        .name("iac-everyone-server-1")
        .region("nyc1")
        .size("s-1vcpu-512mb-10gb")
        .build());
});

Module 5: Configuration with Ansible

While OpenTofu/Pulumi create the virtual “hardware”, Ansible takes care of what runs inside (Configuration). It is an agentless tool that uses YAML to define tasks.

- name: Configuring the web cluster
  hosts: web-server
  tasks:
    - name: Installing nginx
      apt:
        update_cache: yes
        pkg:
          - nginx
          - postgres
          - redis

Final Project: Real Case

The workshop culminated with a complete deployment of a balanced architecture:

  1. OpenTofu to create 3 web servers and a Load Balancer.
  2. Ansible to install Nginx on the servers and configure HAProxy on the load balancer.
flowchart LR
    subgraph Internet
        Clients["Clients"]
    end

    subgraph DO ["DigitalOcean"]
        LB["HA Proxy (Load Balancer)"]
        Web1["web-server-01"]
        Web2["web-server-02"]
        Web3["web-server-03"]
        
        LB --> Web1
        LB --> Web2
        LB --> Web3
    end

    subgraph Local
        Controller["Controller Node (Ansible/OpenTofu)"]
    end

    Clients --> LB
    Controller --> DO

Conclusion

Infrastructure as code is not just a tool; it’s an automation-first mindset. Whether you use CLI, DSLs, or programming languages, the goal remains the same: reliable, repeatable, and documented infrastructure.

Resources