Milestone 2: Full Environment

You will extend milestone 1 into a complete multi-tier environment: web, app, and data subnets behind a load balancer, secured with NSGs and observed with Azure Monitor. By the end you will have a production-shaped topology.

Learning Objectives

Add app and data subnets with scoped NSGs.
Front the web tier with a load balancer.
Connect monitoring and alerts.
Time: ~10 hours · Difficulty: Advanced · Prereqs: Milestone 1 completed.

Architecture Overview

graph TD LB[Load Balancer] --> Web[Web subnet] Web --> App[App subnet] App --> Data[Data subnet] All[All tiers] --> Mon[Azure Monitor]

Environment Setup

The VNet/VM from Milestone 1.
The Azure CLI and a Log Analytics workspace.

Step-by-Step Execution

Add app and data subnets

az network vnet subnet create --vnet-name vnet -n data --address-prefixes 10.0.3.0/24

Front the web tier with a load balancer

az network lb create -n web-lb --sku Standard --frontend-ip-name fe --backend-pool-name web-pool

Connect monitoring

$ az monitor diagnostic-settings create --name diag --resource $LBID --workspace $WID

"provisioningState": "Succeeded"

Progress So Far

graph LR A[01 Subnets] -->|done| B[02 Load balancer] B -->|done| C[03 Monitoring] style A fill:#1a4a1a,stroke:#00ff00,color:#fff style B fill:#1a4a1a,stroke:#00ff00,color:#fff style C fill:#1a4a1a,stroke:#00ff00,color:#fff

Testing & Validation

curl -s -o /dev/null -w "%{http_code}\n" http://$(az network public-ip show -n web-lb-ip --query ipAddress -o tsv)

The load balancer front end should return 200 from a backend VM, and tiers should only talk to adjacent tiers. Milestone 2 is complete.

Troubleshooting

LB returns no response: add a health probe and ensure backend pool membership.
Tier reachable it should not be: tighten the subnet NSG rules.
No diagnostic data: confirm the diagnostic setting targets the workspace.

Extension Ideas

Promote the whole build to the Cloud Capstone.
Replace VMs with AKS.
Codify the environment with IaC.

Key Results

Extended to a 3-tier topology with scoped NSGs.
Load-balanced the web tier behind a public front end.
Connected diagnostics and monitoring.
Achieved a production-shaped environment.

Azure Milestone 2: Full Multi-Tier Environment