🌐 Azure Load Balancer & High Availability Infrastructure

Production-grade Azure High Availability Infrastructure implementing Azure Load Balancer, Health Probes, Backend Pools, Availability Sets, Traffic Distribution, Failover Validation and Enterprise Networking Design.

---

📌 Project Overview

This project demonstrates enterprise-grade Azure networking implementation focused on building highly available backend infrastructure capable of automatic traffic distribution and failover handling.

Implemented capabilities:

✅ Azure Standard Load Balancer

✅ Backend Pool Architecture

✅ Health Probe Validation

✅ Multi VM Infrastructure

✅ Automatic Failover

✅ Availability Set Deployment

✅ Azure Compute Gallery

✅ Production-grade Availability Design

---

🎯 Business Requirement

Enterprise applications require:

❌ Zero Single Point Of Failure

❌ Traffic Distribution

❌ Backend Redundancy

❌ Automatic Recovery

❌ Infrastructure Availability

❌ Production-grade Reliability

This project solves those problems using Azure networking and high availability principles.

---

🏗️ Architecture Design

graph TD

User[End User / Internet]

LB[Azure Public Load Balancer]

VM1[Backend Web Server 01]

VM2[Backend Web Server 02]

Probe[Health Probe TCP 80]

User -->|Traffic via Port 80| LB

subgraph Availability_Set_High_Availability

LB -->|Backend Pool Route 1| VM1

LB -->|Backend Pool Route 2| VM2

end

Probe --> VM1

Probe --> VM2

LB --> Probe

Loading

---

⚙️ Core Components Implemented

🌐 Frontend IP Configuration

Public IP mapped with Azure Load Balancer for incoming traffic.

---

🎯 Backend Pool

Collection of backend Virtual Machines responsible for serving application traffic.

Implemented:

✅ Availability Set

✅ Backend Redundancy

✅ Fault Domain Isolation

✅ Update Domain Protection

---

🔍 Health Probes

Configured:

TCP Port 80

Capabilities:

✅ Backend Validation

✅ Health Monitoring

✅ Automatic Traffic Rerouting

✅ Unhealthy VM Removal

---

⚖️ Load Balancing Rules

Configured:

Frontend → Backend Port Mapping

Capabilities:

✅ Traffic Distribution

✅ Availability Protection

✅ High Availability

---

⚙️ Configuration Variables

Modify deployment behavior using:

variables.tf

Variable Name	Description	Default Value
resource_group_name	Azure Resource Group Name	azure-lb-ha-rg
location	Azure Region	East US
vm_count	Backend VM Count	2
vm_size	Azure VM SKU	Standard_B1s

---

⚙️ Technology Stack

Technology	Purpose
Azure	Cloud Platform
Azure VM	Backend Infrastructure
Ubuntu Linux	Operating System
Apache2	Web Layer
PHP	Application Runtime
Azure Load Balancer	Traffic Distribution
Azure Compute Gallery	VM Image Standardization
Azure Health Probe	Backend Monitoring
NSG	Security Rules
PowerShell	Traffic Testing
Azure Monitor	Monitoring

---

🚀 Infrastructure Components

✅ Azure Standard Load Balancer

✅ Backend Pool

✅ Frontend Public IP

✅ Health Probe

✅ Availability Set

✅ Azure Monitor

✅ Compute Gallery

✅ NSG Rules

---

🚀 Deployment Process

1️⃣ Linux VM Deployment

Installed:

sudo apt update

sudo apt install apache2 php -y

Configured:

• Apache
• PHP
• Website Files

---

2️⃣ Azure Compute Gallery

Created:

• Image Definition

• Image Version

Benefits:

✅ Faster Provisioning

✅ Standardization

✅ Repeatable Infrastructure

---

3️⃣ Secondary VM Deployment

Provisioned second backend VM.

Validated:

✅ Same Runtime

✅ Same Application

✅ Same Configuration

---

4️⃣ Load Balancer Configuration

Configured:

• Frontend IP

• Backend Pool

• Health Probe

• Load Balancing Rule

---

5️⃣ Backend Pool Configuration

Added backend servers.

Capabilities:

✅ Traffic Distribution

✅ Backend Redundancy

✅ Failover Protection

---

6️⃣ Health Probe Validation

Configured:

TCP Port 80

Validated:

✅ VM Health Validation

✅ Backend Monitoring

✅ Automatic Failover

---

📈 Load Balancing Configuration

Configuration	Value
Protocol	TCP
Frontend Port	80
Backend Port	80
Probe Type	TCP
Probe Port	80
SKU	Standard

---

🚦 Traffic Simulation & Load Testing

PowerShell Validation:

1..5000 | % { Start-Job { Invoke-WebRequest http://LOADBALANCER-IP } }

Observed:

✅ CPU Increase

✅ Traffic Distribution

✅ Backend Balancing

✅ Stable Availability

---

🔥 Failover Testing

Scenario:

1. Website opened through LB Public IP

2. Backend VM manually stopped

3. Traffic behavior validated

Result:

✅ Zero Downtime

✅ Automatic Traffic Redirection

✅ Health Probe Operational

✅ Backend Redundancy Working

---

⚠️ Engineering Challenges Solved

Challenge	Solution
Website inaccessible	NSG Rule Configuration
VM deployment standardization	Compute Gallery
Public IP limitation	Dedicated Frontend IP
VM not visible in pool	Network Validation
Health Probe failed	TCP Probe Fix
Needed balancing proof	PowerShell Traffic Testing

---

📸 Project Proof Screenshots

🏗️ Architecture Diagram

---

Validated:

✅ Traffic Distribution

✅ CPU Utilization

✅ Health Probe Behavior

✅ Backend Availability

✅ Failover Validation

Using:

Azure Monitor

---

🧠 Skills Demonstrated

Azure Load Balancer

Azure Networking

High Availability Architecture

Backend Pool Management

Health Probe Configuration

Azure Virtual Machines

Traffic Distribution

Failover Testing

Linux Administration

Azure Monitoring

Cloud Operations

---

📈 Project Outcome

Successfully implemented highly available Azure backend infrastructure supporting:

✅ Traffic Distribution

✅ Automatic Failover

✅ Backend Redundancy

✅ Production-grade Availability

✅ Infrastructure Reliability

---

👨‍💻 Author

Amit Kumar

Cloud Engineer | Azure Administrator | Infrastructure Engineer

GitHub

https://github.com/Akamitt009

LinkedIn

https://www.linkedin.com/in/amit-kumar-657255232/