Azure Load Balancer and Application Gateway

1. Azure Load Balancer Azure Load Balancer is a Layer 4 (TCP/UDP) load balancer that distributes incoming traffic across multiple virtual machines to ensure high availability. Architecture Diagram Example Scenario Two virtual machines (VM1 and VM2) host a web application. Incoming HTTP traffic is distributed evenly. If one VM fails health checks, traffic is routed automatically to the healthy VM. Configuration Steps 1. Create VMs and install web server. 2. Create Public Load Balancer. 3. Configure Frontend IP. 4. Add Backend Pool. 5. Configure Health Probe. 6. Create Load Balancing Rule. 7. Configure NSG rules. 2. Azure Application Gateway Azure Application Gateway is a Layer 7 load balancer that supports SSL termination, path-based routing, and Web Application Firewall (WAF). Architecture Diagram Example Scenario Application Gateway routes traffic based on URL path: /web → Web Server /api → API Server It can terminate HTTPS at the gateway level. Configuration Steps 1. Create backend servers. 2. Create Application Gateway (Standard v2 or WAF v2). 3. Configure Frontend IP. 4. Add Backend Pool. 5. Configure HTTP Settings. 6. Create Listener. 7. Create Routing Rule. 8. Enable WAF if required.