5 ms·
$ host 209.216.230.207 207.230.216.209.in-addr.arpa domain name pointer news.ycombinator.com.
by okasaki 2y ago
$ host 209.216.230.207
207.230.216.209.in-addr.arpa domain name pointer news.ycombinator.com.
- mr_mitm 2y agoNot sure what you are trying to tell me. This isn't guaranteed to work. If you define a reverse lookup record for your domain, then that counts as published in my book.
- drpossum 2y agoThis is correct.
- dspillett 2y agoThat is when there is an explicit PTR record, for instance one of my assigned addresses can be named that way due to: 74.231.187.81.in-addr.arpa. 3600 IN PTR ns2.nogoodnamesareleft.com. in the zone file for that IPv4, but unless they've explicitly configured, or are using a hosting service that does it without asking, this it won't be what is happening. It isn't practical to do a reverse lookup from “normal” name-to-address records like ns2.nogoodnamesareleft.com. IN A 81.187.231.74 (it is possible to build a partial reverse mapping by collecting a huge number of DNS query results, but not really practical unless you are someone like Google or Cloudflare running a popular resolution service)
- DonHopkins 2y agoI love how the ARPANET still lives on through reverse DNS PTRs. https://www.youtube.com/watch?v=V78GUSOS-EM https://www.youtube.com/watch?v=V78GUSOS-EM