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What is a PTR record? Do I need one?
When moving emails to a new email client, you might run into a few technical terms and questions. One of the most common is – what is a PTR record, and why does it matter?
A PTR record is an important email security tool that prevents spam. It’s what your mail server uses to determine who’s actually sending email messages.
Let’s take a deep dive into what a PTR record is and why you absolutely do need one.
PTR Records Explained
A PTR record, also known as a Pointer Record, is a piece of information (a record) that is attached to an email message. The purpose of the PTR record is to verify that the sender matches the IP address it claims to be using.
This email ID check process is also known as reverse DNS lookup. It’s the reverse of the forward DNS lookup process that browsers use to convert a domain name to a numerical address: the IP address.
How DNS Lookup Works
DNS – which stands for Domain Name System – is essentially the internet’s phonebook. It stores identifying information about all the internet’s registered domains.
The DNS lookup process happens instantaneously when you enter a website into your browser’s search bar.
For example, when you enter a domain name, such as www.Intermedia.com, your web browser forwards a request for a record. It does this because it wants the IP address that corresponds to the domain name.
Here’s why: it’s that numerical address that web-connected devices (computers, phones, routers, smart appliances, etc.) use to channel the request and responses of a web user’s session. Not the domain name.
So when a web page loads on your laptop, it’s because a DNS lookup took place. In fact, web and email addresses need to have a corresponding IP address to be able to send data.
How Reverse DNS Lookup Works
This process happens with email too, but in reverse.
- Every email address is attached to a domain name – it’s what follows the @ symbol. For example, @gmail.com or @intermedia.com.
- That domain name is matched to an IP address.
- When you enter an email address, the mail server (the equivalent of a postal mail carrier) matches the receiver’s IP address to the destination. It’s the same thing as a mail carrier matching the address on the outside of an envelope with an actual street address, except this is happening digitally.
- The mail server also verifies the identity of the sender by using the IP address to obtain the domain name. This is called reverse DNS lookup, and it’s where PTR records are involved.
The PTR record is the data verifying that the IP address matches the domain name, and it’s the reverse of the “A record,” which provides the IP address associated with the domain.
- Here’s what the A record for a forward DNS record might look like:
xyzcompany.com > 4.123.998.21
- And here’s what a reverse DNS lookup PTR record might look like:
4.123.998.21 > xyzcompany.com
So, a PTR record is simply a normal DNS lookup record in reverse. You can use an external tool like MxToolbox to look up your PTR record.
Why You Need a PTR Record
Mail servers use reverse DNS to ensure the IP address matches the domain name of the sender and hasn’t been taken over by spammers. Having a PTR record ensures a smoother email process and prevents your emails from being sent to your recipients’ spam folders.
Without the PTR record, your email message won’t reach your recipient. That’s because most mail servers will reject an email that doesn’t have one.
Ultimately, without a Pointer Record, mail servers don’t know if an incoming email message is spam – and it’s their job to keep spam messages out of your inbox. So, if there’s no PTR record, email won’t work properly.
Intermedia Makes Email Easy and Secure
To set up a PTR record, you would have to add the record through your admin panel. However, Intermedia’s mail servers have PTR records for all the IP addresses. That means the IP address can be checked against the server’s name without you having to do anything.
Our system also uses an SPF – or Sender Policy Framework – record.
A Sender Policy Framework generates a white list of servers that can send mail on behalf of your domain. It’s an important email security protocol for fighting spam.
When your organization uses Intermedia’s Hosted Exchange service, our IT experts help you add the SPF code to your DNS record. With this code in place, your email recipients’ servers know that Intermedia is authorized to send emails on your behalf.
If you’re using another email server along with Intermedia’s Exchange, you would create a PTR record for that server. Usually, this involves contacting the company that owns the IP address – which is likely your Internet Service Provider (ISP).
You can also contact us for any questions you have regarding Intermedia mail servers and how to create a Pointer Record if you use Intermedia’s Exchange with external mail servers.
Call 800-379-7729 for help. Our friendly support team is available 24/7 and always ready to assist!
You can also learn more by reading our technical article – What Is a PTR Record?