Avatar of Coriron Haz
Coriron Haz
Flag for United Kingdom of Great Britain and Northern Ireland asked on

DNS lookup to public address

Hi all, I was wondering how to achieve the following:

Customers internal domain is company.local
I'm setting up a managed WiFi service for them. For this to work they need to be able to resolve the following:
http://unifi:8080 to my public cloud server which is located in an Azure instance.

I have created a CNAM dns record in my godaddy account for the following: ubnt.provider.tech

This resolves to the public IP address of the server, and i'm able to browse etc without any issues.

How do I configure the customers DNS server to resolve "unifi" to "ubnt.provider.tech" ?
DNSMicrosoft Legacy OSAzure

Avatar of undefined
Last Comment
Brian Murphy

8/22/2022 - Mon
Brian Murphy

Coriron-
Is there a typo in there?

Public DNS consists of minimum two-dot.  So, ubnt.provider.tech the assumption is you own "provider.tech" domain name.

Based on the first example it would be unifi.provider.tech?

You cannot use a short-name unless your plan is to add hosts entries on all the Internet clients?

If the server is already public then it sounds like you want to host a web instance on that server that has the "host header" of "unifi.provider.tech"?

Just want to make sure I understand your question.
Coriron Haz

ASKER
Hi Brian,

I was hoping to add a DNS entry into their DNS server that would translate the short name from unifi to ubnt.provider.tech (i own the provider.tech domain name)

Basically i'm setting up a ubiquiti solution, and by default it does makes an "inform" enquiry to http://unifi:8080/inform

You can use DHCP option 43 to point it to the IP address of your ubiquiti server, or apparently DNS to point "unify" to the IP address / FQDN of your server. This is what i'm trying to achieve. Does that help? (I can cange ubnt.provider.tech to unifi.provider.tech if it helps)
ASKER CERTIFIED SOLUTION
Mal Osborne

THIS SOLUTION ONLY AVAILABLE TO MEMBERS.
View this solution by signing up for a free trial.
Members can start a 7-Day free trial and enjoy unlimited access to the platform.
See Pricing Options
Start Free Trial
GET A PERSONALIZED SOLUTION
Ask your own question & get feedback from real experts
Find out why thousands trust the EE community with their toughest problems.
Coriron Haz

ASKER
Malmensa,

I had actually done this previously, but it wasn't working. I have since added the unifi.provider.tech cname into godaddy, and everything started working properly... i must have missed something somewhere. Nevermind! Thanks!
I started with Experts Exchange in 2004 and it's been a mainstay of my professional computing life since. It helped me launch a career as a programmer / Oracle data analyst
William Peck
Brian Murphy

Thanks for the additional information.

It does raise more questions.

Is ubnt.provider.tech a valid server and have an IP address assigned?

DHCP can only do so much.  Your DNS servers must host this zone:

.provider.tech.

OR

They must have a forwarder or conditional forwarder for provider.tech.

Now, typical DNS query if you don't host that zone would forward to Internet.

The problem typically occurs with "split-DNS"

You could have an internal zone defined in DNS (not AD) that matches provider.tech.

That server might resolve to an internal IP of 10.10.10.5 (example only).

But if I am on the Internet it would resolve to a routable IP address that might be a NAT or VIP on a load balancer.

I think you said the server was accessible from the internet which did throw me off somewhat.

If it does have a routable IP address and your zone is external the answer is somewhat easier.

If you have an Internet accessible IP and you are doing some type of NAT to an internal IP and you have split-dns or split-brain-dns scenario where the zone exists internal and external the answer is somewhat more complicated.

If you only have external DNS and only an internet accessible IP address/server then somewhat easier.

Make sense?