The following key points are important for a better understanding of Azure Private DNS zones:

• Azure DNS supports split-horizon views for private DNS zones, so you can create an internal one for the virtual network, which will be queried by the virtual network only, and another one for the internet-facing queries.
• If you want to enable automatic registration for DNS records for any host within the virtual network, you have to replace the ResolutionVirtualNetworkId parameter with RegistrationVirtualNetworkId.