What is Reverse DNS?
Reverse DNS is the information provided when looking up an IP address. It works in reverse of looking up a domain name, and provides a domain name instead of an IP address. They are also known as PTR records.
Reverse DNS has multiple uses, and is most commonly used by Spam Blacklists. Some blacklists will even block email and blacklist servers purely due to how the reverse DNS is configured.
By default Crucial's reverse DNS is in the following format.
How does this affect my email?
Primarily reverse DNS can result in your server being blacklisted by some third party spam blacklists.
You may find that your server is blacklisted on some of these lists, which will impact your ability to send email from the server.
The main benefit to updating the Reverse DNS is that it will improve the reputation of the server for sending out email, and once a de-listing request is sent, will remove you from blacklists that are blacklisting your server due to this.
How can I fix this?
Some blacklists recommend updating the Reverse DNS to match the primary domain name that is sending out email.
We also highly recommend to have this updated to be the primary domain name that you are using for that IP address.
If you would like to set or update the reverse DNS for your VPS service with Crucial, you will need to submit a request to have this done.