Ask HN: Where to buy Reverse DNS lookup database from?

  • You can look it up yourself, but watch out for CDN's and other third-party services and be aware that not every IP address has a reverse DNS entry. On MacOS:

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    Note that the IP address bytes are reversed in the following command to lookup 18.9.25.15

    host -a 15.25.9.18.in-addr.arpa

    ;; ANSWER SECTION:

    15.25.9.18.in-addr.arpa. 1800 IN PTR dmz-mailsec-scanner-4.mit.edu.

    ---------------------------------------------

    host -a dmz-mailsec-scanner-4.mit.edu

    ;; ANSWER SECTION:

    dmz-mailsec-scanner-4.mit.edu. 1800 IN A 18.9.25.15

    dmz-mailsec-scanner-4.mit.edu. 1800 IN HINFO "VMWARE/VM" "LINUX"