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I got a static IP from my ISP and a domain from GoDaddy. I configured DNS in GoDaddy to point to my static IP. So the website works. However, when I tried to lookup reputation of the IP address, I figured out that the reverse DNS points to my ISP's domain and hostname. I've contacted the ISP for configuring reverse DNS on their end, but they said that they don't provide such a service (though I'm not sure whether the person I talked to has the correct info).

So could you clarify where and how can I configure the reverse DNS? Is it something I can do in Apache/Windows on my computer, or is it something only the ISP can do, or do I need to do this in some 3rd-party websites, or any other situation with reverse DNS?

  • This could be by design. Are you trying to host an email server at home? Many ISPs block SMTP, so I wouldn't be surprised if they refuse to provide rDNS as well. – Maximillian Laumeister Jan 26 at 18:41
  • @MaximillianLaumeister, for now I don't need an SMTP server, I just need a website with decent reputation. Does it harm much if reverse DNS is not set up correctly? But in the future I plan to create an email address at this domain, so if it matters for emailing, then I'm interested too. – Serge Rogatch Jan 26 at 19:07
  • To the best of my knowledge there is no concept of IP address reputation for websites, only for outgoing email servers - that's why I jumped to "email" when you mentioned reputation. And neither IP reputation nor rDNS matter for hosting email at your domain, unless you are a DIY enthusiast and actually running an SMTP daemon on your own hardware. – Maximillian Laumeister Jan 26 at 19:14
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It is indeed something only the ISP can do. Reverse DNS authority is delegated per octet. For example for IPv4 address 185.54.92.1 the reverse DNS record name is 1.92.54.185.in-addr.arpa. That is part of the 92.54.185.in-addr.arpa zone. The holder of 185.54.92.0/24 is the one who maintains that zone. That will be your ISP. If your ISP doesn't let you provide the hostname for that reverse DNS record then there is nothing you can do.

To include Patrick's comment: it is possible for the ISP to delegate parts of the reverse zone to you using the method described in RFC2317. That way you can manage the hostnames yourself. It still does require the ISP to provide this service to you though.

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    Technically, if the current owner of the reverse blocked wanted, it could also delegate parts of it to end clients to let them manage it, see RFC2317 . This is however often clearly not a service offered by typical residential ISP. – Patrick Mevzek Jan 27 at 17:56
  • It unfortunately still depends on the ISPs cooperation... – Sander Steffann Jan 28 at 21:19

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