DNS records provide the connection between the server and the domain name we own. The biggest reason for the development of DNS is that a name, a domain name, is much more understandable and memorable than an ip. Without DNS, your domain name cannot find your server, where DNS can be thought of as a public address, it will guide you. RDNS, on the other hand, is used to confirm where you came from and where you are coming from.
RDNS is important for mail servers. Many major authorities verify that you are a real user by looking at the RDNS record. For this reason, it is absolutely necessary to do it on mail servers. Let's consider RDNS registration with an example.
192.168.0.1 192.168.0.1.in.addr.arpa
Above, we entered a self-assigned address with no RDNS records entered. The RDNS record will reverse this IP address and enable it to reach our server. To do this, we need to enter the address of our server as the RDNS record.
192.168.0.1 mail.parkajans.com.tr
Thus, we arranged our A record and our RDNS record to reach the same address. At the moment, we can reach this address both ways and go through asset checks.
After making your settings, you can check Reverse IP Lookup - MxToolbox to check.