Here is a list of the different DNS record types you could add to your Reverse DNS zone.
The PTR record, or also known as a pointer record, has a very precise and important function. Its goal is to link the IP address to the domain name. In addition, there is a piece of good news, and it is able to perform successfully both with IPv4 addresses and IPv6 addresses. Moreover, this type of DNS record is an essential piece required for you to have Reverse DNS. It is able to exist only in the Reverse DNS zone. So, it would be best if you did not place it in the Forward DNS zone.
Mail servers responsible for receiving messages are required to verify the source of an email. For that purpose, they are going to perform a Reverse DNS lookup in which they are searching exactly for the PTR records.
Thanks to the DNS PTR record, it is a simple task to ensure that the particular IP address (IPv4 or IPv6) is actually linked to that domain name. That way, it is possible to prevent your emails from ending up in the spam folder of your recipients.
The SOA (Start Of Authority) record is going to show the beginning of authority. As a result, it is going to lead to the authoritative name server. It is the one who holds the entire authentic data for the DNS zone. That means it is not a DNS recursive server, which typically holds a duplicate of the DNS information in its cache memory. Therefore, it is essential to have an SOA record for every DNS zone you make.
The NS record is one of the fundamental yet simple DNS record types. For short, it is called NS but it stands for nameserver. It acts as an illustration, such as an ID card for your nameserver. In addition, the NS record serves to define which name server is responsible for the precise DNS zone. In case there is no such record available inside, the DNS zone simply won’t be able to operate at all.
The Name Authority Pointer record, or for short NAPTR record servers for mapping the servers to the users’ addresses in the Session Initiation Protocol (SIP). The NAPTR records and an additional type of DNS record called SRV record allowed the chaining of various records to set complex rewrite rules. As an outcome, they create new domain labels or Uniform Resource Identifiers (URIs).
The short CNAME stands for two different parts. “C” is for canonical, and it is for showing the actual domain name. The part “NAME” is clear to understand, and it is for the hostname. The CNAME record aims to point one hostname to another. With it, you could link several subdomains to the domain name.
In the Reverse DNS zone, a CNAME record is usually used to delegate the IP address management of a smaller range to another DNS server.