What is a PTR record?
The PTR record is one of the essential types of DNS record that is also known as a pointer record. Its main purpose is to associate an IP address to the corresponding domain name. With its help, it is possible to check and prove that the exact IP address is associated with the accurate domain name. Additionally, it confirms that it is not some kind of scam. Thanks to this record, verifying separate elements or services, such as a mail server, is an easy task.
How to start managing PTR records?
Structure
The structure of this type of DNS record is actually very simple. When you decide to create one, you will see the following fields:
- TYPE: In this case, it is PTR.
- Host: Here is the IP address. It could be either an IPV4 address or IPv6 address.
- Points to: Here is the domain name.
- TTL: Here, you determine the TTL (time-to-live) value of a PTR record. Usually, it is not necessary to be low.
Why do you need a PTR record?
PTR record as part of the Reverse DNS provides trust and verifies the IP addresses. If you want to have working, outgoing mail servers, it is required to add a PTR record because of the confirmation methods.
In case when a searcher does not find a pointer record, or it is not configured correctly to associate with an A/AAAA record, during a verification procedure, your emails will end up in SPAM.
Thus, to send an email successfully and it gets to your recipient, you should add a PTR record in a Reverse DNS zone.
Creating your PTR record
It is easy and simple to Create your pointer record. Let’s see how you can do it in several steps.
First step: You have to create Master Reverse Zone
In this zone of your domain, PTR records exist. It is important to remember that it could not be created in a regular Master zone.
After creating the Master Reverse Zone, you should type the IP address in backward order. For illustration, if the IP address is 1.2.3.4, you have to type it as 4.3.2.1. The same rule applies both for IPv4 or IPv6.
Second step: You have to create the pointer record.
An important thing to note is that you will have to make the PTR record in reverse also. Additionally, determine if there is a matching A or AAAA record for each of your PTR records.
Third step: You should add NS records at the IP provider directing to the nameservers. This is an important last step needed to accomplish your Reverse DNS zone.
How to check it?
To check your PTR records, you should do a reverse DNS lookup.
Windows
In the Command Prompt, check with the NSlookup command.
Type:
nslookup 1.2.3.4
Linux or macOS
In the Terminal, check with the dig command.
Type:
dig –x 1.2.3.4
*Just write the IP address you need to see instead of 1.2.3.4.
The result should be the domain name if your query identifies a PTR record.