Day 9 – Infrastructure as Code (IaC) with Terraform & Ansible

Introduction

In today’s DevOps world, Infrastructure as Code (IaC) has changed the way engineers manage and set up IT infrastructure.

Instead of manually configuring servers and networks, IaC lets teams define everything using code—making deployments consistent, repeatable, and easy to scale.

At CuriosityTech.in, we focus on teaching IaC not just for automation, but to help build strong, cloud-native environments.

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What is Infrastructure as Code (IaC)?

IaC means using code (instead of manual steps) to manage and create infrastructure.

It helps DevOps teams to:

1. Automate setup and configuration
2. Keep environments consistent (dev, test, prod)
3. Reduce mistakes and downtime
4. Track changes using version control (like Git)

Think of IaC as a blueprint written in code—every server, database, and network is described clearly, either declaratively or imperatively.

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Types of IaC

IaC Type	Description	Example Tools
Declarative	You define the end result you want. The system figures out how.	Terraform, Kubernetes Manifests
Imperative	You give step-by-step instructions.	Ansible, Chef, Puppet

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Terraform vs Ansible

Two popular IaC tools are Terraform and Ansible. They have different purposes but can work together.

Feature	Terraform	Ansible
Type	Declarative	Imperative
Primary Use	Provisioning infrastructure (VMs, networks, etc.)	Configuring systems and deploying apps
State Management	Tracks state using files	Stateless (depends on idempotent playbooks)
Supported Platforms	AWS, Azure, GCP, Kubernetes, VMware	Linux, Windows, network devices
Learning Curve	Medium	Easy to Medium
Best For	Infrastructure provisioning	Configuration and orchestration

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IaC Workflow (Terraform & Ansible)

Terraform: Declarative Infrastructure Provisioning

Terraform uses HCL (HashiCorp Configuration Language) to define cloud infrastructure.

Workflow:

1. Write Config Files – Define VMs, networks, storage
2. Initialize – terraform init to download plugins
3. Plan – terraform plan to preview changes
4. Apply – terraform apply to deploy resources
5. Manage State – Use terraform.tfstate to track changes

Example – AWS EC2 instance:

provider "aws" {
  region = "us-east-1"
}

resource "aws_instance" "web_server" {
  ami           = "ami-0c94855ba95c71c99"
  instance_type = "t2.micro"

  tags = {
    Name = "WebServer"
  }
}

At CuriosityTech.in, learners start by provisioning VMs and networks in AWS or GCP using Terraform.

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Ansible: Imperative Configuration Management

Ansible is a simple, agentless tool for configuring systems and deploying apps. It uses YAML playbooks that are easy to read and write.

Workflow:

1. Install Ansible – pip install ansible
2. Define Inventory – List of servers
3. Write Playbooks – Define tasks in YAML
4. Run – ansible-playbook site.yml

Example – Install Nginx:

- hosts: webservers
  become: yes
  tasks:
    - name: Install Nginx
      apt:
        name: nginx
        state: present

    - name: Start Nginx
      service:
        name: nginx
        state: started

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Best Practices for IaC

1. Use Version Control (Git) – Track changes
2. Start Small – One VM or container
3. Combine Terraform + Ansible – Provision with Terraform, configure with Ansible
4. Test Changes – Use staging before production
5. Ensure Idempotency – Scripts should run multiple times without breaking anything

At CuriosityTech.in, students do hands-on labs to simulate real-world DevOps work.

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Challenges & Solutions

Challenge	Solution
Large Environment Complexity	Use modules in Terraform and roles in Ansible
Managing State	Store state remotely (e.g., AWS S3 for Terraform)
Learning Curve	Start small, grow complexity step-by-step
Configuration Drift	Reapply playbooks regularly to keep systems aligned

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End-to-End IaC Pipeline (Infographic Summary)

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Conclusion

Infrastructure as Code (IaC) helps DevOps teams manage cloud infrastructure efficiently. Tools like Terraform and Ansible make it easier to automate and scale deployments.

To master IaC, engineers need:

• Knowledge of both declarative and imperative approaches
• Hands-on experience in cloud environments
• Integration into CI/CD pipelines

At CuriosityTech.in, we train learners to provision, configure, and manage real cloud infrastructure using these tools—so they’re ready for enterprise DevOps roles.

By practicing real-world scenarios, engineers gain the skills to build scalable, secure, and reliable systems from the ground up.