What is Infrastructure as Code (IaC) and why is it important?

Infrastructure as Code (IaC) is a method of managing and provisioning infrastructure using code instead of manual processes. It allows:
✅ Automation of infrastructure deployment
✅ Consistency by reducing human errors
✅ Scalability through repeatable scripts

What is Terraform and how does it work?

Terraform is an open-source IaC tool by HashiCorp that helps define and provision infrastructure using a declarative configuration language. It follows three steps:

1. Write: Define infrastructure in .tf files
2. Plan: Preview changes before applying
3. Apply: Deploy and manage resources

Example:

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

resource "aws_instance" "my_instance" {
  ami           = "ami-12345678"
  instance_type = "t2.micro"
}

What is the difference between Terraform and Ansible?

What are Terraform Providers?

Providers are plugins that allow Terraform to manage resources on different platforms (AWS, Azure, GCP, Kubernetes, etc.).

Example:

provider "aws" {
  region = "us-west-2"
}

What is a Terraform State File?

Terraform maintains infrastructure details in a state file (terraform.tfstate), which:
✅ Tracks existing resources
✅ Enables incremental changes
✅ Supports remote storage (e.g., S3, Azure Blob)

What is Ansible and how does it work?

Ansible is an open-source configuration management tool that automates tasks like software installation, updates, and deployments. It works agentless, using SSH or WinRM.

What are Ansible Playbooks?

A playbook is a YAML-based automation script that defines tasks to be executed.

Example (playbook.yml):

- name: Install Nginx
  hosts: web
  tasks:
    - name: Install Nginx
      apt:
        name: nginx
        state: present

What is an Ansible Inventory file?

The inventory file lists managed servers and their details.

Example (inventory.ini):

[web]
server1 ansible_host=192.168.1.10
server2 ansible_host=192.168.1.11

What is AWS CloudFormation?

AWS CloudFormation is an IaC service that provisions AWS infrastructure using YAML/JSON templates.

Example:

Resources:
  MyBucket:
    Type: "AWS::S3::Bucket"

How do you create a CloudFormation stack?

Command:

aws cloudformation create-stack --stack-name my-stack --template-body file://template.yml