Custom Domain and SSL for Azure App Service

This document guides you through the process of configuring a custom domain name and securing it with an SSL certificate for your Azure App Service.

Overview

Azure App Service allows you to host your web applications on a custom domain name (e.g., www.yourcompany.com) instead of the default .azurewebsites.net domain. Furthermore, you can secure this custom domain with an SSL/TLS certificate to enable HTTPS, which is crucial for security and user trust.

Prerequisites

Steps to Configure a Custom Domain

1. Add Your Custom Domain to App Service

Navigate to your App Service in the Azure portal.

In the left-hand menu, under Settings, select Custom domains.

Click Add custom domain.

Enter your custom domain name (e.g., www.yourcompany.com) and click Validate.

Azure will provide you with DNS records (TXT or CNAME) that you need to add to your domain registrar's DNS settings to prove ownership of the domain.

2. Configure DNS Records with Your Registrar

Log in to your domain registrar's website and navigate to the DNS management section.

Add the DNS records provided by Azure. Typically, this involves creating:

Example DNS Configuration (for `www.yourcompany.com`):

Type Host/Name Value/Target TTL
TXT asuid.www {verification_id_from_azure} 3600
CNAME www your-app-service-name.azurewebsites.net 3600

Note: DNS propagation can take some time (minutes to hours). You may need to wait before Azure can validate the records.

3. Validate and Bind the Custom Domain

Once DNS records have propagated, return to the Custom domains section in the Azure portal and click Validate again.

If validation is successful, you will see a Add custom domain button. Click it to bind the domain to your App Service.

Steps to Configure SSL for Your Custom Domain

Securing your custom domain with SSL is essential. Azure App Service supports two primary methods:

Method 1: App Service Managed Certificates

This is the recommended and easiest method for most scenarios.

In the Azure portal, navigate to your App Service, and go to Custom domains.

Find your custom domain in the list. If it's already validated, you will see an option to Add binding or Create certificate.

Click on your custom domain name to open its details.

Click Add binding.

In the SSL certificate section, select Create App Service Managed Certificate.

Click Create.

Once the certificate is created, a new binding will be automatically added. You can then configure your app to redirect HTTP traffic to HTTPS.

Method 2: Importing Your Own SSL Certificate

You will need a PFX file containing your SSL certificate and its private key.

In the Azure portal, navigate to your App Service, and go to TLS/SSL settings.

Under Private Key Certificates (.pfx), click Upload Certificate.

Browse for your .pfx file, enter its password, and click Upload.

Once uploaded, navigate back to Custom domains.

Click on your custom domain name to open its details.

Click Add binding.

In the SSL certificate section, select the certificate you just uploaded from the dropdown list.

Choose the SSL Type (e.g., SNI SSL is common and often sufficient).

Click Add binding.

Enforcing HTTPS

After successfully configuring your custom domain and SSL certificate, it's recommended to enforce HTTPS for all traffic.

Navigate to your App Service in the Azure portal.

Under Settings, select TLS/SSL settings.

Under Protocol Settings, set HTTPS Only to On.

Troubleshooting

For more advanced scenarios, such as using wildcard certificates or Key Vault integration, please refer to the official Azure documentation.

View Official Azure Documentation