DevOps-Danan Infrastructure Architecture & Terraform Modules

Production-grade AWS infrastructure managed with Terraform, featuring high availability across 2 Availability Zones, isolated network tiers, and modular architecture.

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Architecture Diagram

graph TD
    Internet((Internet / End Users))

    subgraph AWS_Cloud ["AWS Region: us-west-1"]
        subgraph VPC ["Dedicated VPC (10.0.0.0/16)"]
            IGW["Internet Gateway"]
            Internet --- IGW

            subgraph Public_Tier ["Public Subnets (DMZ)"]
                subgraph AZ_A_Pub ["AZ: us-west-1a"]
                    PubSub1["Public Subnet 1 (10.0.1.0/24)"]
                    PubEC2["Public EC2 (Nginx Web Server)"]
                    NAT["NAT Gateway + Elastic IP"]
                end

                subgraph AZ_B_Pub ["AZ: us-west-1b"]
                    PubSub2["Public Subnet 2 (10.0.2.0/24)"]
                end
            end

            subgraph Private_Tier ["Private Subnets (Isolated)"]
                subgraph AZ_A_Priv ["AZ: us-west-1a"]
                    PrivSub1["Private Subnet 1 (10.0.11.0/24)"]
                    PrivEC2["Private EC2 (Nginx Web Server)"]
                end

                subgraph AZ_B_Priv ["AZ: us-west-1b"]
                    PrivSub2["Private Subnet 2 (10.0.12.0/24)"]
                end
            end
        end
    end

    IGW --> PubSub1
    IGW --> PubSub2
    PubEC2 --- PubSub1
    NAT --- PubSub1

    PubEC2 -.->|SSH & HTTP (SG Restricted)| PrivEC2
    PrivEC2 -->|Outbound Updates via 0.0.0.0/0| NAT
    NAT --> IGW

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Repository Structure

Devops-Danan/
├── README.md                   # Main repository documentation & guide
├── danan_test.txt              # Test deployment outputs log
├── Note.txt                    # Architecture specification notes
└── terraform/                  # Root Terraform deployment configuration
    ├── README.md               # Terraform deployment instructions
    ├── main.tf                 # Root module invoking child modules
    ├── variables.tf            # Configurable inputs & defaults
    ├── outputs.tf              # Exported endpoints and IPs
    ├── provider.tf             # AWS provider settings
    ├── versions.tf             # Terraform & provider version constraints
    └── modules/                # Reusable Terraform child modules
        ├── README.md           # Module specifications and interfaces
        ├── vpc/                # VPC, subnets, IGW, NAT GW, route tables
        ├── security/           # Public & private security groups
        └── compute/            # EC2 instances & web servers

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Modular Architecture Overview

Module	Location	Description
VPC	modules/vpc	Dedicated VPC with 2 public & 2 private subnets across 2 AZs, IGW, NAT GW, and EIP.
Security	modules/security	Public SG (HTTP/SSH from 0.0.0.0/0) and Private SG (traffic allowed only from Public SG).
Compute	modules/compute	Provisions Public EC2 (with public IP & Nginx) and Private EC2 (behind NAT GW & Nginx).

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Deployment Quickstart

Prerequisites

• Terraform >= 1.5.0
• AWS CLI configured with valid credentials (aws sts get-caller-identity)

Step 1: Initialize

cd terraform
terraform init

Step 2: Validate & Review Plan

terraform validate
terraform plan -out=tfplan

Step 3: Deploy

terraform apply "tfplan"

Step 4: Verify Web Server & Connectivity

# Get public IP
PUBLIC_IP=$(terraform output -raw public_ec2_public_ip)

# Test HTTP response
curl http://${PUBLIC_IP}

Expected response:

<h1>Hello Danan from Public EC2 (...)</h1>

Step 5: Clean Up (Destroy)

To prevent unexpected AWS charges when done testing:

terraform destroy

Caution

The NAT Gateway and Elastic IP incur hourly AWS charges while running. Remember to run terraform destroy when your lab or testing is complete.