azure-architecture-patterns

name	Azure Architecture Patterns
description	Well-Architected Framework principles, reference architectures, and best practices for cloud-native solutions
user-invokable	false

Skill: Azure Architecture Patterns

Well-Architected Framework principles, reference architectures, and best practices for cloud-native solutions.

Metadata

Field	Value
Skill ID	azure-architecture-patterns
Version	1.0.0
Category	Cloud/Infrastructure
Difficulty	Advanced
Prerequisites	Basic Azure knowledge
Related Skills	azure-devops-automation, cognitive-load (for architecture reviews)

---

Overview

Azure architecture is about trade-offs, not perfection. This skill provides structured guidance for designing, evaluating, and optimizing Azure solutions using the Well-Architected Framework (WAF) pillars.

The Five Pillars

Pillar	Focus	Key Question
Reliability	Resiliency, availability	"Will it stay up?"
Security	Protection, compliance	"Is it safe?"
Cost Optimization	Efficiency, value	"Is it worth it?"
Operational Excellence	Manageability, observability	"Can we run it?"
Performance Efficiency	Scalability, responsiveness	"Is it fast enough?"

---

Module 1: Reliability Patterns

Design Principles

1. Design for failure - Assume components will fail
2. Observe health - Know when something is wrong
3. Drive automation - Reduce human error
4. Design for self-healing - Automatic recovery
5. Design for scale-out - Horizontal over vertical

Key Patterns

Circuit Breaker

Prevent cascading failures by failing fast when a downstream service is unhealthy.

// Polly implementation
var circuitBreakerPolicy = Policy
    .Handle<HttpRequestException>()
    .CircuitBreakerAsync(
        exceptionsAllowedBeforeBreaking: 3,
        durationOfBreak: TimeSpan.FromSeconds(30)
    );

Retry with Exponential Backoff

Handle transient failures with increasing delays.

var retryPolicy = Policy
    .Handle<HttpRequestException>()
    .WaitAndRetryAsync(3, retryAttempt => 
        TimeSpan.FromSeconds(Math.Pow(2, retryAttempt)));

Availability Zones

Distribute resources across physically separate datacenters.

Resource	Zone Support
VMs	Zone-redundant or zonal
Azure SQL	Zone-redundant HA
Storage	ZRS, GZRS
App Service	Zone-redundant (Premium)

Reliability Checklist

• Single points of failure identified and mitigated
• Health endpoints implemented (/health, /ready)
• Retry policies with backoff configured
• Circuit breakers for external dependencies
• Availability zones utilized (where supported)
• Disaster recovery plan documented
• RTO/RPO defined and tested

---

Module 2: Security Patterns

Zero Trust Principles

Principle	Implementation
Verify explicitly	Always authenticate/authorize
Least privilege	Minimal necessary permissions
Assume breach	Segment, encrypt, detect

Identity Patterns

Managed Identity

Eliminate credential management with Azure AD-backed identity.

{
  "type": "Microsoft.Web/sites",
  "identity": {
    "type": "SystemAssigned"
  }
}

Use cases:

• App Service → Key Vault secrets
• Azure Functions → Storage access
• VMs → Database connections

RBAC Best Practices

Practice	Rationale
Use built-in roles first	Custom roles add complexity
Scope to resource group	Not subscription (too broad)
Use groups, not users	Easier lifecycle management
Regular access reviews	Remove stale permissions

Network Security

Private Endpoints

Keep traffic on Azure backbone, off public internet.

resource privateEndpoint 'Microsoft.Network/privateEndpoints@2023-05-01' = {
  name: 'pe-storage'
  properties: {
    subnet: { id: subnetId }
    privateLinkServiceConnections: [{
      name: 'plsc-storage'
      properties: {
        privateLinkServiceId: storageAccountId
        groupIds: ['blob']
      }
    }]
  }
}

Network Security Groups (NSG)

Default deny, explicit allow.

Priority	Description
100-200	Allow known good traffic
300-400	Deny known bad traffic
4096	Default deny all

Security Checklist

• Managed identities used (no stored credentials)
• Key Vault for secrets/certificates
• Private endpoints for PaaS services
• NSG/firewall rules explicit deny-by-default
• TLS 1.2+ enforced
• Microsoft Defender for Cloud enabled
• Diagnostic settings → Log Analytics

---

Module 3: Cost Optimization Patterns

Design for Cost

Strategy	Impact
Right-size	Match SKU to actual workload
Reserved Instances	1-3 year commitment = 40-72% savings
Spot VMs	90% discount for interruptible workloads
Auto-shutdown	Dev/test VMs off at night
Serverless	Pay per execution, not idle time

Cost-Aware Architecture

Compute Selection Matrix

Workload Type	Recommended	Why
Steady-state web	App Service Premium	Predictable, manageable
Event-driven	Azure Functions	Pay per execution
Batch processing	Container Apps + KEDA	Scale to zero
Big compute	Spot VMs + Batch	Massive savings
Dev/test	B-series VMs	Burstable, cheap

Storage Tiers

Tier	Use Case	Cost/GB/month
Hot	Frequently accessed	~$0.02
Cool	Infrequent (30+ days)	~$0.01
Archive	Rarely accessed	~$0.002

Lifecycle management: Auto-tier blobs based on last access.

Cost Monitoring

// Azure Resource Graph - find expensive resources
resources
| where type =~ 'Microsoft.Compute/virtualMachines'
| extend vmSize = properties.hardwareProfile.vmSize
| project name, resourceGroup, vmSize, location
| order by vmSize desc

Cost Checklist

• Azure Advisor recommendations reviewed
• Reserved Instances for predictable workloads
• Auto-shutdown for non-prod
• Right-sized based on actual utilization
• Storage lifecycle policies configured
• Cost alerts and budgets set
• Orphaned resources cleaned up

---

Module 4: Operational Excellence Patterns

Infrastructure as Code

Tool	Best For
Bicep	Azure-native, declarative
Terraform	Multi-cloud, state management
ARM	Legacy, avoid for new work
Pulumi	Developers who prefer code

Bicep Best Practices

// Use parameters with descriptions and constraints
@description('The environment name')
@allowed(['dev', 'staging', 'prod'])
param environment string

// Use variables for derived values
var resourcePrefix = 'app-${environment}'

// Use modules for reusability
module storage 'modules/storage.bicep' = {
  name: 'storage-${environment}'
  params: {
    prefix: resourcePrefix
    location: location
  }
}

Observability Stack

Layer	Service	Purpose
Logs	Log Analytics	Centralized logging
Metrics	Azure Monitor	Performance data
Traces	Application Insights	Distributed tracing
Alerts	Azure Alerts	Proactive notification
Dashboards	Azure Workbooks	Visualization

Essential Diagnostic Settings

resource diagnostics 'Microsoft.Insights/diagnosticSettings@2021-05-01-preview' = {
  scope: appService
  name: 'diag-appservice'
  properties: {
    workspaceId: logAnalyticsId
    logs: [
      { category: 'AppServiceHTTPLogs', enabled: true }
      { category: 'AppServiceConsoleLogs', enabled: true }
    ]
    metrics: [
      { category: 'AllMetrics', enabled: true }
    ]
  }
}

Operational Checklist

• IaC for all resources (Bicep/Terraform)
• CI/CD pipelines for deployment
• Diagnostic settings to Log Analytics
• Application Insights integrated
• Alerts for critical metrics
• Runbooks for common operations
• Chaos engineering tests scheduled

---

Module 5: Performance Efficiency Patterns

Scalability Patterns

Horizontal Scaling (Scale Out)

Add more instances, not bigger instances.

Service	Scaling Mechanism
App Service	Autoscale rules
Azure Functions	Event-driven automatic
AKS	Horizontal Pod Autoscaler + Cluster Autoscaler
VMSS	Autoscale rules

Caching Strategy

Cache Type	Use Case	Service
CDN	Static content	Azure Front Door
Distributed	Session, computed data	Azure Cache for Redis
Local	Hot data	In-memory

Performance Patterns

CQRS (Command Query Responsibility Segregation)

Separate read and write models for optimization.

Write Path: Web App → Cosmos DB (write-optimized)
                 ↓ Change Feed
Read Path: Azure Search ← Cosmos DB (indexed, query-optimized)

Event Sourcing

Store events, not state. Rebuild state from event stream.

Benefits:

• Complete audit trail
• Temporal queries
• Easy scaling

Database Performance

Pattern	When to Use
Read replicas	Read-heavy workloads
Sharding	Data exceeds single node
Connection pooling	Many short-lived connections
Indexing strategy	Query performance issues

Performance Checklist

• Autoscaling configured and tested
• CDN for static content
• Redis cache for hot data
• Database indexes reviewed
• Connection pooling enabled
• Load testing completed
• Performance baselines established

---

Reference Architectures

Web Application (Standard)

Internet → Front Door (CDN, WAF) → App Service
                                    ↓
                              Azure SQL + Redis Cache
                                    ↓
                              Key Vault, Storage

Microservices (Azure Kubernetes Service)

Internet → API Management → AKS Ingress
                              ↓
                        Service Mesh (pods)
                              ↓
                        Cosmos DB, Service Bus
                              ↓
                        Azure Monitor, Key Vault

Serverless (Event-Driven)

Event Sources → Event Grid → Azure Functions
                                   ↓
                              Cosmos DB, Storage
                                   ↓
                              Logic Apps (orchestration)

---

Quick Reference

SKU Selection Guide

Tier	CPU	Memory	Use Case
B-series	Burstable	Variable	Dev/test
D-series	General	Balanced	Most production
E-series	Memory-optimized	High	In-memory databases
F-series	Compute-optimized	Low	CPU-intensive

Common Anti-Patterns

Anti-Pattern	Problem	Fix
Monolithic deployment	All or nothing	Microservices or modular
Hardcoded config	Environment-specific	App Configuration, Key Vault
Single region	No DR	Multi-region with Traffic Manager
Over-provisioned "just in case"	Wasted cost	Right-size + autoscale
No IaC	Drift, manual errors	Bicep/Terraform everything

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Module 6: MCP Tool Integration

Required Extensions & MCP Servers

Component	ID / Name	Purpose
VS Code Extension	ms-azuretools.vscode-azure-github-copilot	Azure GitHub Copilot integration
VS Code Extension	ms-azuretools.vscode-azureresourcegroups	Azure resource management
VS Code Extension	ms-vscode.azure-account	Azure authentication
MCP Server	azure-mcp	40+ Azure tools (cloudarchitect, docs, services)

Installation:

# VS Code Extensions
code --install-extension ms-azuretools.vscode-azure-github-copilot
code --install-extension ms-azuretools.vscode-azureresourcegroups
code --install-extension ms-vscode.azure-account

# MCP Server (via VS Code settings.json or mcp.json)
# Enabled via chat.mcp.gallery.enabled = true

Fallback Patterns (When MCP Unavailable)

If Azure MCP tools are not available, use these alternatives:

MCP Tool	Fallback Approach
cloudarchitect	Use WAF Assessment: https://aka.ms/waf-assessment
documentation	Search https://learn.microsoft.com/azure/architecture
get_bestpractices	Reference Azure Architecture Center patterns
Service-specific tools	Use Azure Portal or az CLI directly

Manual Architecture Design Process:

1. Review WAF pillars checklist in Module 1-5
2. Use Azure Architecture Center reference architectures
3. Validate with Azure Advisor in portal
4. Apply patterns from this skill's modules

Available Azure MCP Tools

Alex has access to 40+ Azure MCP tools for real-time architecture assistance:

Category	Tools	Use Cases
Architecture Design	mcp_azure_mcp_cloudarchitect	Interactive architecture design, WAF guidance
Documentation	mcp_azure_mcp_documentation	Search Azure docs, best practices
Best Practices	mcp_azure_mcp_get_bestpractices	Code gen, deployment, Functions patterns
Compute	mcp_azure_mcp_aks, mcp_azure_mcp_appservice, mcp_azure_mcp_functionapp	Container orchestration, web apps, serverless
Data	mcp_azure_mcp_cosmos, mcp_azure_mcp_sql, mcp_azure_mcp_postgres	Database recommendations
Security	mcp_azure_mcp_keyvault, mcp_azure_mcp_role	Secrets management, RBAC
Monitoring	mcp_azure_mcp_monitor, mcp_azure_mcp_applicationinsights	Observability setup
DevOps	mcp_azure_mcp_deploy, mcp_azure_mcp_azd	Deployment automation

Cloud Architect Tool

The mcp_azure_mcp_cloudarchitect tool provides interactive guided architecture design:

Invocation → Ask about user/company → 
  Gather requirements → 
    Build architecture by tier → 
      Present with ASCII diagrams

Architecture Tiers:
├── Infrastructure (VNets, VMs, Load Balancers)
├── Platform (App Service, AKS, Functions)
├── Application (Logic Apps, API Management)
├── Data (SQL, Cosmos, Storage)
├── Security (Key Vault, WAF, DDoS)
└── Operations (Monitor, Log Analytics)

The tool tracks:

• Explicit requirements — Directly stated by user
• Implicit requirements — Inferred from context
• Assumed requirements — Industry/domain defaults

Best Practices Tool

Use mcp_azure_mcp_get_bestpractices with these resource/action combinations:

Resource	Actions
codegen	all — Code generation patterns
deployment	all — Deployment best practices
functions	all — Azure Functions patterns
swa	all — Static Web App guidance
coding-agent	all — MCP setup for repos

When to Use MCP Tools

Scenario	Tool	Why
"Design new Azure solution"	cloudarchitect	Interactive, pillar-aligned
"What's the best way to..."	documentation	Search official docs
"Generate Azure code"	get_bestpractices + specific tools	Current patterns
"Cost optimization review"	cloudarchitect + monitor	Full picture
"Security assessment"	keyvault + role + documentation	Multi-tool analysis

Example: Interactive Architecture Session

User: "Design a solution for a retail e-commerce platform"

Alex invokes: mcp_azure_mcp_cloudarchitect with:
  - intent: "Design e-commerce architecture"
  - nextQuestionNeeded: true
  - state: {initial}

Tool asks: "What's your role and company size?"
User: "CTO of a mid-size retailer"

Tool continues gathering:
  - Expected traffic patterns
  - Data residency requirements  
  - Budget constraints
  - Compliance needs (PCI-DSS for payments)

Tool outputs:
  - Component table with SKU recommendations
  - ASCII architecture diagram
  - WAF pillar alignment
  - Cost estimation

---

Activation Patterns

Trigger	Response
"Azure architecture", "cloud design"	Full skill activation
"reliability", "high availability", "resilience"	Module 1
"security", "zero trust", "identity"	Module 2
"cost", "optimize", "savings"	Module 3
"IaC", "Bicep", "observability"	Module 4
"performance", "scaling", "caching"	Module 5
"MCP", "cloud architect tool", "Azure tools"	Module 6
"design architecture interactively"	Invoke cloudarchitect tool

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Skill updated: 2026-02-14 | Category: Cloud/Infrastructure | Status: Active | MCP-Enhanced: Yes

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Synapses

• [.github/skills/observability/SKILL.md] (High, Enables, Bidirectional) - "Monitoring and observability patterns"
• [.github/skills/project-scaffolding/SKILL.md] (Medium, Uses, Forward) - "Infrastructure-as-code project setup"
• [.github/instructions/empirical-validation.instructions.md] (Medium, Validates, Forward) - "Architecture decisions require evidence"