> On Oct 28, 2016, at 6:04 PM, Karl Auer <ka...@biplane.com.au> wrote: > >> 1b) anti spam filters believe in the magic of checking >> forward/reverse match. > > Someone in this thread said that only malware-infested end-users are > behind IP addresses with no reverse lookup. Well - no. As long as we > keep telling anyone who isn't running a full-bore commercial network to > "consume, be silent, die", we are holding everyone back, including > ourselves.
If you send mail over IPv6 from an address with no reverse DNS you will see quite a lot of this sort of thing: 550 5.7.1 [*] Our system has detected that this message 5.7.1 does not meet IPv6 sending guidelines regarding PTR records and 5.7.1 authentication. Please review 5.7.1 https://support.google.com/mail/?p=ipv6_authentication_error for more 5.7.1 information. > > It's fine to use no-reverse-lookup as a component of a spamminess > score. It's not OK to use it as proof of spamminess. People running large mailservers made that decision some time ago. Disagreeing with them won't make them accept your email. Cheers, Steve
