Conventional DNS involves the resolution of a name, easily understood and remembered by people, to numeric addresses, used by computers. Reverse DNS was designed to allow the opposite process, the pointing of the numbers back to the appropriate names.

Setting up reverse DNS isn't required for the majority of domains. However, some servers block connections from IP addresses that do not have reverse DNS set up and some mail servers will not accept email from mail servers that do not have reverse DNS set up. If you are encountering this kind of issue with your domain name then Reverse DNS can be very useful.

There are 2 sides to having reverse DNS set up, both of which need to be completed for it to function.

1. The IP block must be delegated to our nameservers by your ISP
2. The appropriate DNS records, called PTR records, must be set up in our servers