This article will provide you with an overview of Microsoft Azure DNS, focusing on custom and default DNS services provided by Microsoft Azure.
Microsoft Azure DNS is a hosting service that provides name resolution for DNS domains using Microsoft Azure infrastructure. It’s a service that helps you do name resolution for your resources in Azure. By default, you’ll have two types of DNS services in Azure: default DNS, which is provided by Microsoft by default, and custom DNS, which is your own DNS server.
The default DNS provided by Microsoft has a domain called internal.cloudapp.net. Whenever you create any virtual machines and do the name resolution, it uses internal.cloudapp.net along with your VM name to do the name resolution. For example, if your VM name is VM1, the result will come with VM1.internal.cloudapp.net.
Custom DNS is your own DNS server, whether it’s on-premises or built in Azure. If you have your own DNS server, you can use that DNS server on your V-net so that all the name resolution will happen using your own DNS server instead of the default one.
In an Azure environment, let’s say you have a V-net and a subnet, and under this subnet, you have created a VM which is VM1 and VM2. If there is no DNS configured, then name resolution will fail. To overcome this, Microsoft provides the default DNS, which is internal.cloudapp.net. Whenever you do a name resolution for this VM or that VM, the result will be VM1.internal.cloudapp.net, and it will give you the IP address as a result of your name resolution.
To use custom DNS, you need to use something called custom domain configuration. In your V-net, you need to mention the DNS IP address of your DNS server. Once you have configured your custom DNS, all your name resolution will use this DNS server to do the name resolution. Whenever you do any name resolution, it will do the name resolution with VM1.vdibus.site, and it will give you the IP address accordingly.