Azure DNS name (servername.location.cloudapp.azure.com) VS internal FQDN (hostname.domain name eg servername.acad.ac.uk) - are they both FQDN?

Question

Hi all,

a somewhat petty question that is bugging me.
When I created a VM in our azure subscription, it has the DNS name in the format of
servername.location.cloudapp.azure.com

Which apparently is a FQDN
(where servername is the hostname and location could be northeurope etc)

However when I log onto the server and check its name via ping -a IP or full computer name it comes out as as:
servername.acad.ac.uk
(where acad is generic UK institution)

Apparently that is a FQDN as well.
Is there concept of internal and external (Azure) FQDN - or what I am misunderstanding?

many thanks

Answer 1

@Tom I understand that you have questions regarding the Azure FQDN i.e., when you create the VM and add a DNS name in the Portal as shown below:

However, you do not see the same name once you login to the Server/VM in Azure. Is this what you are concerned about? Please correct me otherwise.

The FQDN that is provided here is for the Public IP of the VM. Once you login to the server/VM and do a nslookup for the hostname, you will see the hostname of the private IP of the VM.

In this case, what you are seeing(servername.acad.ac.uk) seems like a private DNS name. Can you confirm what DNS server you are using for this VM/Vnet? Usually it shows up in the NSLOOKUP output.

Thank you!

Answer 2

Please go through it.

https://learn.microsoft.com/en-us/azure/virtual-machines/create-fqdn

Also Check

https://stackoverflow.com/questions/15289835/fqdn-on-azure-virtual-machine