Wietse Venema:
> postfix:
> > Mail from our system wasn't accepted oftentimes by Google either.
> > I discovered the following solution: Our mail server has got two IPv6
> > addresses in the open Internet, one is specific, the other one
> > automatically created. The first one was in the DNS, the second one not.
> > I noticed that many times messages where sent using the automatically
> > generated IPv6 address, which were the mails Google rejected. Since I
> > introduced the automatically generated IPv6 address into the DNS, Google
> > accepts all mail from our server.
>
> Solutions other than turning off IPv6 autoconfiguration on servers:
That remains my preferred solution, but it may not be possible if
you don't control the infrastructure.
> - Specify all Postfix IP addresses in main.cf:inet_interfaces.
>
> /etc/postfix/main.cf:
> inet_interfaces = 1.2.3.4 127.0.0.1 1:2:3:4:5:6:7:8 ::1
That example is wrong. inet_interfaces does not restrict the SMTP
client IP address when there more than one.
> - Specify the Postfix IPv6 address in master.cf:
>
> /etc/postfix/master.cf:
> relay ... smtp -o smtp_bind_address6=1:2:3:4:5:6:7:8
> smtp ... smtp -o smtp_bind_address6=1:2:3:4:5:6:7:8
That example is good. It uses master.cf instead of main.cf, to avoid
conflicts with content filters.
Wietse
