reverse DNS

rDNS: Do you really need it?

Reverse domain name system or rDNS is a really useful feature. But the reality is, it’s not a must to have it. It totally depends on the kind of domain you have. Answering more specifically, yes, you really need rDNS if you plan to send e-mails or provide any other service requiring DNS verification to operate.

If your domain doesn’t have such requirements, no, you don’t need to enable rDNS. Simple as that. If you want to understand properly what is rDNS and what it is for, this entire article is for you! Maybe you don’t need rDNS now, but you can need it later!

What is rDNS?

In the context of DNS requests, the most common operation is a forward DNS lookup. Meaning, a domain name is typed on a browser, therefore a DNS lookup takes place to search the IP address associated with that domain.

Reverse DNS (rDNS) is a DNS lookup of a domain name from a specific IP address. It’s exactly the opposite operation. That’s the reason it was named like this.

To enable rDNS you require a DNS PTR (DNS pointer) record to save the reverse DNS entries. Then, you have to input the reversed IP address’ components, plus “.in-addr.arpa”. For instance, for IP 12.23.34.45, its reverse DNS entry would be 45.34.23.12.in-addr.arpa.

The rDNS usually comes included as a service or feature in managed DNS plans. If yours doesn’t include it, for sure, you can buy it. What you are going to get is the possibility to generate a reverse DNS zone for your PTR records to be added.

Reverse DNS works with IPv4 (A) and IPv6 (AAAA). You don’t have to choose one or the other. Both can be used.

Why do I need rDNS?

Let’s be crystal clear, without rDNS, users will successfully reach your domain. That is a common confusion. rDNS utility points to the following. 

  • By adding PTR records to the reverse DNS zone, you are creating proof to guarantee there’s a match between the IP address and the domain name. This way, other companies’ servers can verify it and be protected from scammers.
  • In other words, using rDNS, e-mail servers (receivers) can check the IP address (sender) of every incoming message. If the match between the IP address and the domain name is validated, messages will be admitted as legit.
  • It helps to filter spam. Criminals send e-mails to potential victims using trustable and legit domain names (banks, taxation, health, insurance entities, etc.). Receiver servers can verify messages’ legitimacy and filter the risk.
  • It ensures your clients really get your messages. If your last e-mail MKT campaigns, promotions, special sales, etc., haven’t succeeded, consider that your e-mails can be going directly to the spam folder. rDNS can fix it!
  • It provides trustability to your domain for clients to know you are a legit product or service supplier.
  • Some cloud services, data storage, backup services, office applications, and more require DNS validation. Without it, they won’t work.

Conclusion

As you see, rDNS has real and useful functionality. Once you analyze it, chances for you to need it now or later are big. Considering how dangerous the Internet has become, deleting the risk of being considered as not trustable is vital. It can totally make a difference in terms of income for your business. If you need it now, enable it. If not, keep this information in mind. It could save you later!