Reverse DNS – What is it?

Reverse DNS or, for short rDNS maps an IP address to its corresponding domain name. It acts in the opposite direction of Forward DNS, where the domain name points to the corresponding IP address. Typically rDNS is offered by DNS hosting providers as an additional service. However, when you decide to use it, you should also create a Master Reverse zone and PTR records. Thanks to them, you will be capable of providing proof that the exact IP address and your domain name actually match.

The PTR record, also known as a pointer record, serves to link the IP address (IPv4 or IPv6) with the domain name. In addition, the Master Reverse zone is needed for storing your PTR record. 

This service is a perfect opportunity to avoid any attempts for fraud. Moreover, you improve the overall trustability of your services.

Why use Reverse DNS?

• By using Reverse DNS and adding your PTR records, you provide to other companies evidence that the IP address and the domain name are matching. Additionally, they are protected from any criminal attempts.
• The email servers of your correspondents can check the PTR record and confirm the message is coming from a legit source. 
• rDNS improves the trustability of your domain name. It establishes a positive image of a legit service. 
• It is a great way to filter spam. Typically, cybercriminals send emails to their victims and use the domain names of trustable organizations, such as banks. Yet, with Reverse DNS, such messages are filtered, and the recipients are protected by fraudulent attempts.
• In some cases, DNS verification is essential. Let’s say, for example, cloud services, backup services, data storage, office applications, and others. 
• Reverse DNS is helpful in cases when you want to be sure that your message for sure will get to your clients. With it, you avoid your email MKT campaigns, promotions, special sales to end up in the spam folders of your recipients. 

How to check your Reverse DNS?

You are able to perform a Reverse DNS lookup by simply checking the IP addresses and examining if they point to the correct hostname. It is actually a very simple and easy task to complete. On the majority of the popular operating systems (OS), such as Linux, Windows, and macOS, you can easily use a tool called the Nslookup command. 

• First, you should open the Command Prompt for Windows and the Terminal app for Linux and macOS. 
• Then, just type the following: nslookup 122.134.13.21

*Just make sure to change the IP address in the example (122.134.13.21) with the one you want to check. You can place both IPv4 and IPv6 addresses.

Conclusion

So now you know how beneficial it is to implement Reverse DNS. It could be extremely necessary when you want to verify your services, or you want to ensure the delivery of your email messages. In addition, it is simple and easy to check it.