Design 50: The Ultimate Architecture (Masterpiece)

Summary

This is the Final Capstone Design. It combines Hub & Spoke, Global DR, Zero Trust, Hybrid Identity, and Mission Critical principles into one massive, enterprise-grade architecture.

Topology: A Global Mesh of Hubs and Spokes, protected by Firewalls, managed by Arc, and powered by Data Mesh.

1. Key Design Decisions (ADR)

ADR-01: Everything

Decision: Apply all previous 49 designs.
Rationale: This represents a real-world Fortune 500 environment.

2. High-Level Design (HLD)

                                  GLOBAL TRAFFIC MANAGER
                                           |
                  /------------------------+------------------------\
                  |                                                 |
                  v                                                 v
        +------------------+                              +------------------+
        | REGION A (East)  |                              | REGION B (West)  |
        |                  |                              |                  |
        |   [HUB VNet]     |                              |   [HUB VNet]     |
        |   - Firewall     |<--(Global VNet Peering)----->|   - Firewall     |
        |   - VPN Gateway  |                              |   - VPN Gateway  |
        |   - Bastion      |                              |   - Bastion      |
        |                  |                              |                  |
        +--------+---------+                              +--------+---------+
                 |                                                 |
      /----------+----------\                           /----------+----------\
      |          |          |                           |          |          |
      v          v          v                           v          v          v
  [Spoke A]  [Spoke B]  [Spoke C]                   [Spoke A]  [Spoke B]  [Spoke C]
  (Web App)  (AKS)      (Data)                      (Web DR)   (AKS DR)   (Data DR)

3. Low-Level Design (LLD)

+-----------------------------------------------------------------------+
| MANAGEMENT GROUP: Corp                                                |
|   Policy: Require-Tags, Allowed-Locations, Deny-Public-IP             |
+-----------------------------------------------------------------------+
                                    |
+-----------------------------------------------------------------------+
| SUBSCRIPTION: Connectivity                                            |
|   [vWAN Hub] or [Hub VNet]                                            |
|     |-- Azure Firewall Premium (IDPS)                                 |
|     |-- ExpressRoute Gateway (to On-Prem)                             |
|     |-- Private DNS Resolver                                          |
+-----------------------------------------------------------------------+
                                    |
+-----------------------------------------------------------------------+
| SUBSCRIPTION: Landing Zones (Spokes)                                  |
|   [Spoke 1: Online Store]                                             |
|     |-- App Gateway (WAF) -> AKS Cluster                              |
|     |-- Redis Cache (Private Link)                                    |
|     |-- SQL Database (Private Link)                                   |
|                                                                       |
|   [Spoke 2: Analytics]                                                |
|     |-- Synapse Workspace                                             |
|     |-- Data Lake Gen2                                                |
+-----------------------------------------------------------------------+

4. Component Rationale

Landing Zones: Pre-provisioned subscriptions with networking/policy ready for app teams.

5. Strategy: High Availability (HA)

Layers:

* Global: Front Door.

* Region: Availability Zones.

* App: Load Balancers.

6. Strategy: Disaster Recovery (DR)

RPO/RTO: Defined per service tier (Tier 1 = 15 mins, Tier 3 = 24 hours).

7. Strategy: Backup

Vault: Central "Backup Vault" in a separate subscription (Cyber Recovery) protected by Resource Guard.

8. Strategy: Security

SIEM: Microsoft Sentinel ingesting logs from all Firewalls, Identity, and Endpoints.

9. Well-Architected Framework Analysis

Reliability: 5/5.
Security: 5/5.
Cost Optimization: 3/5. Expensive, but optimized via Reservations/Savings Plans.
Operational Excellence: 5/5. Fully automated via Bicep/Terraform.
Performance Efficiency: 5/5.

10. Detailed Traffic Flow

1. User: Hits contoso.com.

2. Global: Front Door routes to East US.

3. Hub: Traffic enters Hub Firewall (Inspection).

4. Spoke: Routed to Spoke AKS Ingress.

5. App: Microservice processes request.

6. Auth: App calls Entra ID for token.

7. Data: App reads from SQL (Private Link).

8. Log: All telemetry sent to App Insights & Sentinel.

11. Runbook: Deployment Guide (Azure Portal)

Phase 1: The Foundation (Hub)

1. Deploy Design 05 (Hub VNet):

* Create vnet-hub-east and vnet-hub-west.

* Peer them (Global VNet Peering).

2. Deploy Design 20 (Firewall):

* Deploy Azure Firewall Premium in both Hubs.

* Configure Network Rules to allow Spoke-to-Spoke traffic.

3. Deploy Design 11 (VPN):

* Deploy VPN Gateway in vnet-hub-east.

* Connect to On-Premises.

Phase 2: The Governance

1. Deploy Design 27 (Policy):

* Assign "NIST 800-53" Initiative to the Management Group.

* Assign "Allowed Locations" (East US, West US).

2. Deploy Design 28 (Budgets):

* Set a monthly budget of $5000.

* Configure alerts at 50% and 80%.

Phase 3: The Workloads (Spokes)

1. Deploy Design 17 (Web App Spoke):

* Create vnet-spoke-web. Peer to Hub.

* Deploy App Service Environment or App Service VNet Integration.

2. Deploy Design 33 (AKS Spoke):

* Create vnet-spoke-aks. Peer to Hub.

* Deploy Private AKS Cluster.

3. Deploy Design 45 (Data Spoke):

* Create vnet-spoke-data. Peer to Hub.

* Deploy Synapse and Data Lake.

Phase 4: The Connection (Mesh)

1. Peering: Ensure all Spokes are peered to their regional Hub.

2. Routing: Create Route Tables (UDR) in all Spoke Subnets.

* Route 0.0.0.0/0 -> Firewall Private IP.

3. DNS: Link all Private DNS Zones (privatelink...) to the Hub VNets.

Phase 5: The Final Test (Chaos Engineering)

1. Simulate Ransomware:

* Try to download a test virus (EICAR) on a VM.

* Verify Defender for Endpoint blocks it.

2. Simulate Region Failure:

* "Break" the East US Hub (e.g., Deny All rule in Firewall).

* Verify Front Door routes traffic to West US.

3. Simulate User Spike:

* Run a load test (Azure Load Testing).

* Verify AKS scales up nodes.