Benny Pedersen via Postfix-users wrote in <a95aa4938b2c4e228a80b2d8eb3fb...@junc.eu>: |Jos Chrispijn via Postfix-users skrev den 2024-05-15 11:25: |> Can someone explain why bl.spamcop.net reverses the ipv6 ip, thus not |> recognizing it like postscreen?
This is the usual way to do reverse lookups. RFC 1034 from 1987: 2. Host address to host name translation This function will often follow the form of previous functions. Given a 32 bit IP address, the caller wants a character string. The octets of the IP address are reversed, used as name components, and suffixed with "IN-ADDR.ARPA". A type PTR query is used to get the RR with the primary name of the host. For example, a request for the host name corresponding to IP address 1.2.3.4 looks for PTR RRs for domain name "4.3.2.1.IN-ADDR.ARPA". This was then taken over to IPv6, and got a bit lengthy. --steffen | |Der Kragenbaer, The moon bear, |der holt sich munter he cheerfully and one by one |einen nach dem anderen runter wa.ks himself off |(By Robert Gernhardt) _______________________________________________ Postfix-users mailing list -- postfix-users@postfix.org To unsubscribe send an email to postfix-users-le...@postfix.org