Recently a customer of mine was having trouble accessing an App Service through an IPv6 connection. From the office accessing the App Service was working, but several colleagues was having problems accessing the App Service from their home connection. The ISP already transitioned from the IPv4 to the IPv6 protocol. It was an requirement to have the App Service IPv6 ready, because the app services where running an federal government public website (Government regulations require new applications to be accessible to IPv6-only clients).
The solution for this is using Azure Front Door (https://docs.microsoft.com/en-us/azure/frontdoor/front-door-overview](https://docs.microsoft.com/en-us/azure/frontdoor/front-door-overview). AFD works as a frontend and supports IPv6.
First I created an Azure Web App (afdtest.azurewebsites.net), an given it an custom domain name (appservice.sscfit.nl) tested the site if it’s IPv6 ready (http://ipv6-test.com/validate.php): The app service is not IPv6 ready.
Setting up Azure Front Door
- First thing to do is create an Azure Front Door service (currently in preview) in the Azure portal. In the configuration blade you can name the subdomain on the Front's door default domain. My front door host name is sscfit.azurefd.net.
- The next step is to add a backend pool. For this example I have one App Service as a backend. The settings for the Health probes and Load balancing are ok with the default settings.
- The final configuration is to create a routing rule. I’ve named it AcceptAll, and left everything else to default.
- It will take about 2 hours for the Front Door service to work. When browsing the AFD URL I see the App Service website.
Add Custom domain to Azure Front Door
The have an own domain name visible for end-user requests, it is possible to setup a custom domain name for Azure Front Door. To accomplish this, a CNAME record must be created with the domain provider to point to the AFD default front end host. A custom domain and its sub-domain can be associated with only a single Front Door at a time. However, you can use different sub-domains from the same custom domain for different Front Doors by using multiple CNAME records. You can also map a custom domain with different sub-domains to the same Front Door.
Next step is to associate the custom domain with Azure Front Door. In the Azure portal, go to the Azure Front Door service. Under settings > Front Door designer, click on the + by Frontend hosts. Here you can fill in the custom host name I’ve also added a CNAME for www and added this to the AFD frontend hosts My App Service is now accessible through the custom domain linked to the AFD. And very important, my App Service is IPv6 ready