PGNet Dev:
> cat ./local/smtp_dns_reply_filter.pcre
> # <- Wietse Venema:
> # force IPv4 for all domains that have Google as an MX host.
> # This drops all AAAA records from Google MX hosts,
> # effectively forcing Postfix to deliver over IPv4.
> # /domain ttl IN AAAA address/ action, all case-insensitive.
> # Note: the domain name ends in ".".
> /^\S+\.google.com\.\s+\S+\s+\S+\s+AAAA\s+/ IGNORE
>
> where
>
> grep smtp_dns_reply_filter main.cf
> smtp_dns_reply_filter =
> pcre:/usr/local/etc/postfix/local/smtp_dns_reply_filter.pcre
>
> per the comment, i must've added that 'on advice' here at ML.
>
> unfortunately, my notes are missing any ML date/reference (looking
> for it ...) :-/ afaik, could've been 'my' problem, or google's.
>
> i _suspect_ it's due to (for now) my public postfix IP binds service
> only on IPv4 -- i.e.,
>
> -o smtp_bind_address=$var_MX1_IPv4
That setting has no effect on Postfix IPv6 behavior. What documentation
suggests otherwise?
> offhand, is that generally needed/beneficial for google.com MXs?
I don't know, does anyone want to be the guinea pig and discover
if they still randomly bounce email over IPv6?
Wietse
