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If you are using the same firewall, it could be the NAT is wrong, so you are going out on the wrong IP address.<br />
<br />
Simon.
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If you are using the same firewall, it could be the NAT is wrong, so you are going out on the wrong IP address.

Simon.

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Thanks guys, I've never had to do this before, didn't realize my old boss had setup originally and we've just been using it.<br />
<br />
I gave AT&amp;T a call and they were happy to help add a reverse PTR for our IP address, contrary to what I had read on the internet.
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Thanks guys, I've never had to do this before, didn't realize my old boss had setup originally and we've just been using it.

I gave AT&T a call and they were happy to help add a reverse PTR for our IP address, contrary to what I had read on the internet.

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We currently have two networks running on two separate IP address spaces. We had to move our exchange server from one to the other. Now we are getting failed reverse DNS lookup NDRs.<br />
<br />
Our MX records are showing the correct IP address, when I ping the mail server from outside the network the correct IP address shows up. However, when I use mxtoolbox.com's smtp tester I get the error that SMTP reverse banner check is failing and we are getting numerous NDRs due to lack of reverse DNS.<br />
<br />
What am I missing?<br />
<br />
Please let me know what information I need to provide to help you solve this issue.
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We currently have two networks running on two separate IP address spaces. We had to move our exchange server from one to the other. Now we are getting failed reverse DNS lookup NDRs.

Our MX records are showing the correct IP address, when I ping the mail server from outside the network the correct IP address shows up. However, when I use mxtoolbox.com's smtp tester I get the error that SMTP reverse banner check is failing and we are getting numerous NDRs due to lack of reverse DNS.

What am I missing?

Please let me know what information I need to provide to help you solve this issue.

Exchange 2010 reverse DNS not working

Exchange is the server side of a collaborative application product that is part of the Microsoft Server infrastructure. Exchange's major features include email, calendaring, contacts and tasks, support for mobile and web-based access to information, and support for data storage.

Exchange

Networking is the process of connecting computing devices, peripherals and terminals together through a system that uses wiring, cabling or radio waves that enable their users to communicate, share information and interact over distances. Often associated are issues regarding operating systems, hardware and equipment, cloud and virtual networking, protocols, architecture, storage and management.

Networking

The Domain Name System (DNS) is a hierarchical, globally distributed system responsible for associating the name of a computer, service or other resource into an IP address for connecting to the Internet or a private network. Most prominently, it translates domain names to the numerical IP addresses needed for the purpose of computer services and devices worldwide.