So I have purchased this domain, say mydomain.com, and would like to use it for my lab in the cloud.

I spinned up a new service in Azure, say myservice, and built a new VM called mydc, promoted it to domain controller and configured a new forest mydomain.com, all default settings in Server 2012 R2. I am able to RDP into the new DC VM from the internet via myservice.cloudapp.net:[Azure Endpoint] and [Public IP]:[Azure Endpoint], but not via mydc.mydomain.com:3389 (or no port at all).

Should I login to the domain provider's interface and configure something to point to my Azure VM, maybe the DNS zone file ? and any extra config required on my VM ?

[this might belong on Server Fault, but figured out it must be quite a basic question on DNS, so tried here first]

  • Don't forget DNS takes time to propagate. What is TTL for the domain set at? – Tyson Mar 23 '15 at 13:51
  • TTL is 600 seconds, can't go lower than this in the interface. – Razvan Zoitanu Mar 23 '15 at 13:54
  • That's 10 minutes which is good, but allow 20 in practice, you might use whatsmydns.net but i suspect the real issue might be your local DNS cache, fastest way to check is pick up your phone or any second device using a differnt network and DNS and test. – Tyson Mar 23 '15 at 14:01
  • Pinging mydc.mydomain.com (VM firewall is off) solves to the same IP shown on whatsmydns.net, and that's different than the Public IP of my VM. So that would explain why RDP to the VM on mydc.mydomain.com also fails at this point. I'd wait some more, but it's been more than an hour and I'm quite sure I need to change some settings somewhere first. Maybe the nameservers ? As I have the DNS role installed on my VM, should I just use the Public IP of the VM as Nameserver in the provider's DNS interface ? – Razvan Zoitanu Mar 23 '15 at 14:33
  • Tyson, thank you for the link to the site, really useful in order to understand how this works. – Razvan Zoitanu Mar 23 '15 at 17:00

All that was required was a new A record. Had to go to the domain provider's DNS interface, edit the DNS Zone file, add a new A record (mydc) that points to my VM's Public IP.

Less than 2 minutes later, whatsmydns.net shows that mydc.mydomain.com resolves everywhere to this Public IP. RDP to the VM is now available on mydc.mydomain.com:[Azure RDP Endpoint].

  • since you don't seem to know where the previous A record came from you might use whatsmydns to check for an AAAA record, If one exists it an IPv6 address that likely matches the server for the previous A record. If your VM doesn't have an IPv6 address or you don't know how it's configured then just delete the bad AAAA record for now. – Tyson Mar 23 '15 at 18:49
  • There's no AAAA record. And there was no A record before I added one. There was only a @ host configured, pointing to the seller's servers, guess that's the default. – Razvan Zoitanu Mar 24 '15 at 11:38

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