A PTR record or DNS pointer record provides the domain name associated with a specific IP address. It is the opposite of an ‘A’ record that provides the IP address that is associated with a specific domain name.
In other words, PTR records are used for verification and mail servers use them to verify that emails come from the locations that they appear to come from. Because of this, most email servers search PTR records when checking for spam. PTR records can be configured for both IPv4 and IPv6, although the format differs for each.
What are PTR Records used for?
PTR records are used in reverse DNS lookups. In simple terms, when an Internet user tries to reach a domain name in their browser, A DNS lookup occurs and matches the domain name to an IP address. A reverse DNS lookup is the opposite of this, and the query starts with the IP address and the process looks up the domain name associated with a specific IP address.
The main uses for reverse DNS lookups where PTR records are used are:
- Spam prevention: Some spam filters use reverse DNS lookups to determine whether an IP address associated with a specific domain name is used by legitimate email servers.
- Troubleshooting email delivery issues: Because they play a role in identifying spam email, a misconfigured or missing PTR record might result in deliverability issues in email. This is simply because if a domain doesn’t have a PTR record or if the specific domain’s PTR record contains incorrect information, email servers may block any email coming from that domain.
- System logs: Typically, system logs only record IP addresses. Therefore, to make sense of a system log, reverse DNS lookups can convert these IP addresses into domain names that make the log easier to read.
Why is PTR Record Important?
Because email is an integral part of any business, it’s crucial to take the necessary steps to prevent issues with email deliverability. In fact, Google recommends properly configured PTR records as part of its best practices. They’re easy to set up and they can save time and prevent problems when it comes to email deliverability.
Not only does this make the email process smoother, but it also provides credibility to users. In this way, emails are delivered, and they don’t get blocked or sent to spam folders.