5.1.3. Public DNS Zone

A Public DNS Zone in Azure is also a prerequisite. Use the following steps, originally from the OpenShift tutorial, to create one.

• Identify your domain, or subdomain, and registrar. You can transfer an existing domain and registrar or obtain a new one through Azure or another source.
  For more information about purchasing domains through Azure, see Buy a custom domain name for Azure App Service in the Azure documentation.

• If you are using an existing domain and registrar, migrate its DNS to Azure. See Migrate an active DNS name to Azure App Service in the Azure documentation.

• Configure DNS for your domain. Follow the steps in the Tutorial: Host your domain in Azure DNS in the Azure documentation to create a public hosted zone for your domain or subdomain, extract the new authoritative name servers, and update the registrar records for the name servers that your domain uses.
  Use an appropriate root domain, such as openshiftcorp.com, or subdomain, such as clusters.openshiftcorp.com.

• If you use a subdomain, follow your company’s procedures to add its delegation records to the parent domain.