Hub & Spoke Network Architecture

🚀 Overview

This project demonstrates deploying a Hub & Spoke network topology in Azure with Firewall, NAT Gateway, and VNet peering. Uses Terraform (IaC) + Portal + CLI.

✅ What I Built

• 1 Hub VNet with Azure Firewall and NAT Gateway
• 2 Spoke VNets (connected via peering)
• 2 Linux VMs (one in each spoke)
• Network Security Groups (NSGs)
• VNet Peering (Hub ↔ Spoke)
• Firewall rules for traffic control

📍Architecture

Spoke VNet 1          Hub VNet          Spoke VNet 2
┌─────────────┐   ┌──────────────┐   ┌─────────────┐
│  VM Linux   │   │  Firewall    │   │  VM Linux   │
│  10.1.1.x   │───│  NAT Gateway │───│  10.2.1.x   │
│   NSG       │   │  10.0.0.0/16 │   │   NSG       │add
└─────────────┘   └──────────────┘   └─────────────┘
   (peering)         (central hub)       (peering)

📍Technologies Used

• Infrastructure: Terraform (IaC)
• Networking: Azure VNet, Peering, Firewall, NAT
• Compute: 2 Linux VMs (Ubuntu 20.04)
• Security: NSGs, Firewall rules
• Tools: Azure Portal, Azure CLI, Cloud Shell

🎯 How to Deploy

📍Phase 1: Infrastructure with Terraform

cd terraform
terraform init

terraform validate

terraform plan

terraform apply

Terraform creates:

• Hub VNet (10.0.0.0/16)
• 2 Spoke VNets (10.1.0.0/16, 10.2.0.0/16)
• Subnets in each VNet
• 2 Linux VMs
• Firewall Subnet
• NAT Gateway Subnet
• Network Interfaces
• Public IPs

📍Phase 2: Portal configuration

• Configure Firewall Rules
• Create Application Rules
• Create NSG

🎯 My Contributions to This Project

Using Terraform (IaC)

✓ Deployed all infrastructure with terraform apply ✓ Created 2 VNets, 3 Subnets per spoke ✓ Deployed Azure Firewall & NAT Gateway ✓ Configured network interfaces ✓ Created Linux VMs with cloud-init

Using Azure Portal

✓ Created firewall application rules ✓ Created firewall network rules ✓ Configured NSG rules manually ✓ Verified peering connections ✓ Monitored traffic in diagnostic logs

Using Azure CLI / Cloud Shell

✓ Connected to VMs via SSH ✓ Tested ping between VMs ✓ Checked effective NSG rules ✓ Monitored firewall logs