On Tue, Sep 26, 2023 at 02:01:24PM -0400, Wietse Venema via Postfix-users <postfix-users@postfix.org> wrote:
> Wietse Venema via Postfix-users: > > Wietse Venema via Postfix-users: > > > It's a rather long explanation for "why not do X". like several > > > times longer than the text that explains what protocol preferences > > > do. And this is the only place where adding that text would help. > > > > I updated the text a little: > > I'm adding a section to smtp_address_preferences, about when not > to use this setting. > > Wietse > > Notes for mail delivery between sites that have both IPv4 and IPv6 > connectivity: > > * Some remote SMTP servers will flag messages received over IPv6 > as more 'spammy' than messages received over IPv4. This may be > because the Postfix SMTP client's IPv6 address lacks a proper > PTR record, or because the client shares an IPv6 address block > with bad users. > > To achieve consistent delivery performance, don't tweak the > smtp_address_preference setting; instead, receive mail over > both IPv4 and IPv6, and deliver mail only over IPv4. > > /etc/postfix/main.cf: > inet_protocols = all > > /etc/postfix/master.cf > smtp ...other fields... smtp -o inet_protocols=ipv4 > > * The setting "smtp_address_preference = ipv6" is unsafe. [Existing > text omitted for brevity] Should -o inet_protocols=ipv4 also be added to the relay directive? cheers, raf _______________________________________________ Postfix-users mailing list -- postfix-users@postfix.org To unsubscribe send an email to postfix-users-le...@postfix.org
