In general the deposition of a Reverse DNS entry takes place at the provider of the IP address. This can be the hosting provider, webspace provider or internet service provider. Please ask your respective provider.
Exception: If you are owner of your own IP network:
In case you are operating a IP network and the internet service provider can change your reverse zone to our DNS, you can manage your reverse DNS entries with us.
If the zone is not existing yet, you can add one by following the subsequent steps:
Log into the customer area.
Click on Nameserver on the left side menu of the customer area.
Click on the Add domain button.
Enter the zone into the field Domain. For example 123.123.123.in-addr.arpa
Choose our NS-Set and remove Webserver and Mailserver if those entries were given.
Click on Add.