What is a PTR Record?

PTR records are used for the Reverse DNS (Domain Name System) lookup. Using the IP address you can get the associated domain/hostname. An A record should exist for every PTR record. The usage of a reverse DNS setup for a mail server is a good solution.

While in the domain DNS zone the hostname is pointed to an IP address, using the reverse zone allows to point an IP address to a hostname. In the Reverse DNS zone, you need to use a PTR Record. The PTR Record resolves the IP address to a domain/hostname.

Why you need a PTR records?

PTR records provides trust that the given hostname or a domain are connected to the IP address. The PTR records are must have for outgoing mail servers, because most of the mail providers reject or mark as spam messages received by mail servers without valid reverse dns configuration (missing PTR or mismatch A record for the hostname).

How to create PTR record?

In order to create a PTR record, please contact support.  You will need to provide your IP address and a  fully qualified domain you would like it to resolve into. 

The PTR records has the following look:

After creating the PTR record, make sure that the hosts have corresponding A records. In our example, hostname1.example.com must be with A record pointed to 192.168.0.1 and hostname2.example.com with 192.168.0.2