Setting up a reverse DNS (PTR) record

A reverse DNS (PTR) record tells which hostname an IP address belongs to; it is the opposite of a normal DNS record. If you send email from your server, receiving servers usually check whether the sending IP has a valid reverse DNS record. If it is missing or doesn’t match your domain, your email may end up in spam.

Before you start: the A record

The hostname you want to use (for example mail.example.com) must first have an A record pointing to your server’s IP address. Reverse DNS and the A record should confirm each other, otherwise the record won’t help. To add an A record see DNS records.

Setting the reverse DNS record

1. In the customer panel open your server from My services and go to the Manage tab.
2. In the IP addresses box click the Reverse DNS link next to the IP address.
3. Enter the full name in the Hostname field (for example mail.example.com).
4. Save. A “Reverse DNS saved” message appears; the record propagates after a short while.

Checking it

dig -x 203.0.113.21 +short
host 203.0.113.21

You should see the hostname you set. If you still see an old result, wait a few minutes and try again.

Tip: if you are running a mail server, make the hostname match the server’s HELO/EHLO name too and set SPF, DKIM and DMARC records for your domain. See Business email for details.