AZ-104 Exam EP 25: Azure Load Balancer

Introduction

This tutorial provides a comprehensive overview of Azure Load Balancer, a critical component for distributing network traffic and ensuring high availability of applications in Microsoft Azure. Whether you're preparing for the AZ-104 exam or looking to enhance your cloud infrastructure knowledge, this guide will walk you through the core concepts and functionalities of Azure Load Balancer.

Step 1: Understand Azure Load Balancer

• Azure Load Balancer is a Layer 4 (TCP, UDP) load balancer that distributes incoming traffic among healthy instances of services in a cloud environment.
• It ensures that no single instance is overwhelmed with traffic, improving responsiveness and availability.

Step 2: Explore Public Load Balancer

• Public Load Balancer directs traffic from the internet to your virtual machines (VMs) or service endpoints.
• Key features:
  • Assigns a public IP address to the load balancer.
  • Routes external traffic based on configured rules.

Step 3: Explore Internal Load Balancer

• Internal Load Balancer is used to manage traffic between internal resources.
• It supports communication within a virtual network (VNet) without exposing it to the internet.
• Key features:
  • Assigns a private IP address.
  • Ideal for applications that do not need public access.

Step 4: Review Load Balancer SKUs

• Azure offers different SKUs for Load Balancers:
  • Basic SKU: Cost-effective and includes limited features.
  • Standard SKU: More advanced features, higher performance, and better security.
• Choose the SKU that aligns with your application needs and budget.

Step 5: Configure Backend Pools

• Backend pools define which resources the Load Balancer will distribute traffic to.
• Steps to configure:
  • Navigate to the Azure portal.
  • Select your Load Balancer.
  • Go to the "Backend pools" section.
  • Add VMs or VM scale sets to the pool.

Step 6: Set Up Load Balancer Rules

• Load Balancer rules define how traffic is distributed among backend pool instances.
• To create a rule:
  • Open the Load Balancer in the Azure portal.
  • Go to the "Load balancing rules" section.
  • Click on “Add” and configure the necessary settings (frontend IP, backend pool, protocols, and ports).

Step 7: Implement Session Persistence

• Session persistence (also known as sticky sessions) ensures that traffic from the same client is directed to the same backend instance.
• Configure session persistence by:
  • Selecting the "Session persistence" option in your Load Balancer rule.
  • Choosing the required persistence method (None, Client IP, or Client IP and protocol).

Step 8: Configure Health Probes

• Health probes monitor the health of backend instances to ensure they are capable of handling traffic.
• Steps to set up health probes:
  • Go to the Load Balancer in the Azure portal.
  • Click on "Health probes."
  • Add a probe by specifying the protocol, port, and interval settings.

Conclusion

In this tutorial, you learned about the Azure Load Balancer, including its types, configuration, and key features. Understanding how to effectively implement Azure Load Balancer is crucial for ensuring your applications are resilient and perform optimally. For your next steps, consider exploring the Azure documentation further or practice configuring a Load Balancer in your Azure environment.