Hi, On 9/10/2018 11:37 PM, endre.szabo@nanog-list-kitfvhs.redir.email wrote:
I wonder how they generate these rDNS PTR records? I was always curious, hope someone knows.
I do it for our various IPv6 (and IPv4) allocations by using PowerDNS with a remote backend. If there is no existing PTR record defined the query gets sent to the remote backend which generates the PTR based on the IP address. The same thing happens for A/AAAA record requests, if the A/AAAA record for the PTR does not exist it will also be generated based off the hostname provided as long as the hostname matches a record that would have an automatic PTR generated. Originally I was using the pipe backend with a modified copy of "PowerDNS-Dynamic-Reverse-Backend" (https://github.com/endreszabo/PowerDNS-Dynamic-Reverse-Backend) but ended up writing my own in Perl as the backend was a bit fragile and didn't do everything I wanted.