Azure App Service

Learning objectives#

• Explain App Service plans and apps
• Create and deploy an app with the Azure CLI
• Configure app settings and connection strings
• Use deployment slots and scaling

Explanation#

An App Service plan defines the compute — region, instance size and count. One or more apps run inside a plan and share its resources and cost.

App settings in Azure override appsettings.json at runtime and are exposed as environment variables. Store secrets in Key Vault and reference them from app settings.

Deployment slots (Standard tier and above) let you deploy to a staging slot, warm it up, then swap it into production with no downtime — and swap back if something goes wrong.

Code example: Deploy an ASP.NET Core API with the Azure CLI#

1# Sign in and create a resource group
2az login
3az group create --name rg-techie-demo --location centralindia
4

5# Create a Linux App Service plan (B1 = Basic tier)
6az appservice plan create --name plan-techie-demo --resource-group rg-techie-demo \
7  --sku B1 --is-linux
8

9# Create the web app on .NET 9
10az webapp create --name techie-demo-api --resource-group rg-techie-demo \
11  --plan plan-techie-demo --runtime "DOTNETCORE:9.0"
12

13# Configure settings (become environment variables)
14az webapp config appsettings set --name techie-demo-api --resource-group rg-techie-demo \
15  --settings ASPNETCORE_ENVIRONMENT=Production
16

17# Publish and deploy
18dotnet publish -c Release -o ./publish
19cd publish && zip -r ../app.zip . && cd ..
20az webapp deploy --name techie-demo-api --resource-group rg-techie-demo --src-path app.zip --type zip

The API is available at https://techie-demo-api.azurewebsites.net

This example is illustrative. Copy or download it and run it in your own environment; the expected output is shown above.

Step-by-step explanation#

1. A resource group holds everything for the project, so you can delete it all at once.
2. The plan sets the size (B1) and OS (Linux).
3. webapp create creates the app inside the plan with the .NET 9 runtime.
4. App settings configure the environment without changing code.
5. dotnet publish builds a release package; az webapp deploy uploads it.

Real-world use case#

Common mistakes#

Best practices#

• Use managed identity to access other Azure resources
• Enable Application Insights
• Use deployment slots for zero-downtime releases
• Set a budget alert on the subscription
• Automate deployments with GitHub Actions or Azure Pipelines

Remember this#

Practice exercise#

1az webapp config connection-string set --name techie-demo-api --resource-group rg-techie-demo \
2  --connection-string-type SQLAzure --settings Default="<your-connection-string>"

Mini quiz#

Want more? Practise all Microsoft Azure MCQs · Microsoft Azure interview questions

Related topics#

My notes#

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