Automatic rDNS (Auto-PTR)
Xenyth Cloud simplifies reverse DNS (rDNS) management with our Auto-PTR feature. This allows you to automatically generate Pointer (PTR) records for all IPs within a given range using a simple templating format. This is particularly useful for dynamically assigning PTR records to your VMs, dedicated servers, or other services.
What is Reverse DNS?
Reverse DNS resolves an IP address to a hostname, which is the opposite of a typical (forward) DNS lookup that resolves a hostname to an IP. PTR records are used for this. Many online services, especially email servers, perform rDNS checks as a security measure to validate the source of a connection.
How Auto-PTR Works
Our system allows you to define a wildcard record within a reverse DNS zone. This record serves as a template to dynamically generate PTR records for any IP address within that zone.
Step 1: Create an rDNS Zone
First, you need to create a reverse DNS zone for your IP range in the Xenyth Cloud dashboard.
- Navigate to the DNS section of the dashboard.
- Create a Basic or better DNS service, with the appropriate ARPA zone, check your RIR or LIR to see what your ARPA zones should be.
Step 2: Create a Wildcard PTR Record
Once the zone is created, you can add a wildcard record to it.
- In your new rDNS zone, click Add Record.
- For the record name/host, enter a wildcard
*. - In the content/value field, enter your desired template. The system will replace a placeholder with the IP address being looked up.
IPv4 Templating
For IPv4 addresses, the placeholder %5% represents the full IP address, with each dot (.) replaced by a hyphen (-).
- Template:
%5%.static.as835.net - IP Address:
192.168.1.1 - Resulting PTR Record:
192-168-1-1.static.as835.net
IPv6 Templating
For IPv6 addresses, the placeholder %33% represents the compressed IPv6 address. Colons (:) are replaced with hyphens (-).
- Template:
%33%.static6.as835.net - IP Address:
2001:a::1 - Resulting PTR Record:
2001-a--1.static6.as835.net