From today, those of you who use dedicated IP addresses for your sites and applications will be able to also add a PTR record to them.

A PTR record, also known as a reverse DNS record, maps an IP address to a domain name, which is opposite to what an A record does.

PTR records allow you to perform a reverse DNS lookup to check if a given IP address is associated with a particular domain/hostname.

Why are PTR records needed?

With a PTR record set, your site will be able to resolve in both directions (from a domain name to an IP address through an A record and from an IP address to a domain name through a PTR record), which will help you build a trusted image for your online presence in external DNS lookups.  

Here is how a DNS lookup on a site will look like with the two records set:

Also, the reverse DNS record plays a crucial part in SPAM prevention in email delivery by helping verify the authenticity of the outbound email server.  

By setting a PTR record for an IP address, you add extra tracing to the origin of an email, and hence contribute a pinch of credibility to the email server itself.

The addition of a PTR record is further necessitated because of the fact that some incoming mail servers will not even consider accepting a message from an IP address that does not identify itself with a PTR record in a reverse DNS zone.

How to set up a PTR record?

By default, we do not assign a reverse DNS record to a newly added dedicated IP address to your web hosting account:

However, you can specify a value of your choice in the ‘Not Set’ field at any time and thus create a reverse DNS zone for your dedicated IP address.

Generally, PTR records are input in a very specific format where you need to start with a portion of your IP address written backwards, followed by .in-addr.arpa.

We have facilitated that procedure for you by doing all the special formatting in the background automatically. As a result, all you will have to do is specify the hostname that the IP address is mapped to in the PTR Record field: