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+---
+title: "Setup rDNS"
+tags: ['mail']
+date: 2022-12-02
+---
+
+While [DNS records](/basic/dns) refer a domain name to the IP address
+where the the website is hosted, there is also rDNS (reverse DNS) and
+specifically PTR (pointer) records which do the reverse: link a
+server\'s IP to a domain name.
+
+This is important for many things, but especially email. Many email
+servers require that other servers that send them mail have PTR records
+to prevent spam.
+
+## Setting your PTR Record
+
+DNS settings are set with your registrar, while rDNS settings are set
+with your server or VPS provider. **Remember to set records for both
+IPv4 and IPv6!**
+
+In [Vultr](https://www.vultr.com/?ref=8384069-6G) we want to set the
+IPv4 record, click on the server, then \"Settings,\" and make sure the
+\"IPv4\" tab is selected. We can then edit the \"Reverse DNS\" blank
+shown below.
+
+{{< img alt="IPv4 rDNS PTR record set in Vultr" src="/pix/rdns-01.png" >}}
+
+The setting for IPv6 is obviosuly under the IPv6 tab. Note here that we
+copy the full IPv6 address from above and create a new rDNS entry by
+pasting that and the domain name in the blanks below. Then just select
+\"Add.\"
+
+{{< img alt="IPv6 rDNS PTR record set in Vultr" src="/pix/rdns-02.png" >}}
+
+That\'s it!