SMTP over IPv6 : gmail classifying nearly all IPv6 mail as spam since 20140818

Daniel Austin daniel at
Fri Aug 22 10:09:08 CEST 2014


On 22/08/2014 08:56, Laurent GUERBY wrote:
> Hi,
> We've been running SMTP over IPv6 with postfix successfully for over a
> year and since 20140818 IPv6 MX started to classify most IPv6
> sourced emails sent from our machine to as spam. The exact
> same message sent using IPv4 within one minute of the IPv6 bounce is
> accepted.
> As there's no way to reach google mailops we had to remove IPv6 from our
> mail machines and go back to IPv4 only for mail, which is sad.
> Are we alone with this recent experience?

gmail are still accepting IPv6 mail from my server - most recent message 
was 2 hours ago.
(they do seem to put most IPv6 transacted mail into spam folders on the 
receiving side however!)

They also reject any IPv6 transacted mail without valid reverse dns.



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