Deploying Web Apps with Azure App Services: A Complete Beginner's Guide

📘 Chapter 3: Configuration, Scaling, and Performance Optimization

🔍 Overview

Once your web application is deployed to Azure App Services, the next step is to ensure it's configured properly, scales effectively, and runs with optimal performance. This chapter provides a comprehensive walkthrough of advanced configuration options, environment setup, autoscaling rules, diagnostic tools, and real-world performance best practices.

🛠️ 1. App Settings and Configuration Management

Azure App Services allows you to define environment-specific configurations directly through the App Settings section, similar to environment variables in traditional development.

🔹 Why Use App Settings?

• Securely store app-level environment variables
• Override application configurations per environment (e.g., dev, staging, prod)
• Inject secrets (via Azure Key Vault integration)

✅ Add App Settings via CLI

bash

az webapp config appsettings set \

  --name mywebapp \

  --resource-group MyResourceGroup \

  --settings NODE_ENV=production API_URL=https://api.example.com

🧪 Best Practices

• Use separate resource groups for staging and production
• Use descriptive keys (e.g., APP_MODE, CONN_STR_DATABASE)
• Avoid hardcoding secrets—integrate with Key Vault

🔐 2. Integrating Azure Key Vault for Secrets

To protect sensitive values like API keys or DB passwords:

1. Store Secret in Key Vault

bash

az keyvault secret set --vault-name MyVault \

  --name DB-Password --value "MySecurePass123"

2. Reference in App Setting

Use the following format:

less

@Microsoft.KeyVault(SecretUri=https://MyVault.vault.azure.net/secrets/DB-Password/)

🔒 App must have permission to access the Key Vault.

⚙️ 3. Platform and Runtime Configuration

You can control aspects like:

• .NET version or Node.js runtime
• 32-bit or 64-bit architecture
• Startup commands for custom entry points
• Application stack auto-updates

✅ Example: Set .NET Core Version via CLI

bash

az webapp config set \

  --name mywebapp \

  --resource-group MyResourceGroup \

  --net-framework-version v6.0

🚀 4. Scaling App Services: Manual vs Autoscale

Azure App Services supports both vertical and horizontal scaling.

🔹 Vertical Scaling

Upgrade your App Service Plan for more CPU/RAM:

bash

az appservice plan update \

  --name MyPlan \

  --resource-group MyResourceGroup \

  --sku P1V2

🔹 Horizontal Scaling

Add more instances manually or automatically.

✅ Manual Scaling:

bash

az webapp scale \

  --name mywebapp \

  --resource-group MyResourceGroup \

  --number-of-workers 3

✅ Enable Autoscale:

Via Portal → App Service → Scale Out → Custom Autoscale

📈 Scaling Guidelines

📊 5. Performance Optimization Tips

Performance depends on proper code, configuration, and service usage.

✅ Enable Compression

bash

az webapp config set \

  --resource-group MyResourceGroup \

  --name mywebapp \

  --http20-enabled true \

  --web-sockets-enabled true

Enable Gzip from Azure Portal → Configuration → General Settings.

✅ Use Persistent Storage (if needed)

• Use Azure Blob Storage for media or file uploads
• Avoid using local filesystem unless for temporary data

✅ Keep App Warm

To avoid cold start delays:

• Use Always On (Standard Tier+)
• Send scheduled pings to the endpoint

bash

az webapp config set \

  --resource-group MyResourceGroup \

  --name mywebapp \

  --always-on true

✅ Application Gateway or Front Door

Use Azure Front Door for global routing, SSL termination, and caching.

✅ Caching

• Use in-app caching (Redis, MemoryCache, etc.)
• Integrate with Azure Cache for Redis for enterprise scenarios

🧪 6. Monitoring and Diagnostics

🔧 Enable Diagnostic Logs

bash

az webapp log config \

  --name mywebapp \

  --resource-group MyResourceGroup \

  --application-logging true \

  --level information

📂 Log Options

📈 View Performance with Application Insights

Application Insights provides:

• Request counts
• Response times
• Exception tracking
• Live metrics dashboard

Linking:

bash

az webapp config appsettings set \

  --name mywebapp \

  --resource-group MyResourceGroup \

  --settings APPINSIGHTS_INSTRUMENTATIONKEY=<your-key>

📋 Summary Table – Configuration & Scaling Overview