On 4 March 2018 at 23:11, Nick <n...@kousu.ca> wrote: > In smtpd.conf, the "limit mta" line can be qualified like this: > > limit mta for domain gmail.com inet4 > > which I did because I recently started getting bounces from google saying > > 550-5.7.1 [2001:19f0:5001:2f5:5400:ff:fe77:861d] Our system has detected that > this message does not meet IPv6 sending guidelines regarding PTR records and > authentication. Please review > https://support.google.com/mail/?p=IPv6AuthError for more information . > d63si3145626edc.222 - gsmtp
Whilst this is a valid question for OpenSMTPD, from the sysadmin side, the solution is much simpler. Your reverse name is fake, as it does not resolve forward: % host 2001:19f0:5001:2f5:5400:ff:fe77:861d d.1.6.8.7.7.e.f.f.f.0.0.0.0.4.5.5.f.2.0.1.0.0.5.0.f.9.1.1.0.0.2.ip6.arpa domain name pointer comms.kousu.ca. % host comms.kousu.ca. comms.kousu.ca has address 108.61.165.176 % I'm surprised you don't get other hosts rejecting your mail, too; I suspect it may have to do simply with gmail being the monoculture of mail nowadays. My suggestion would be to fix the forward name, else, fix the reverse name to point to something like IPv6.example.org, which you should ensure exists and points back. Sometime ago, making the reverse point back to itself (e.g., a PTR with the value of the IPv6 address itself) also made gmail happy to accept the mail as well, but I'm not too sure if that's still the case. Cheers, Constantine. http://cm.su/
