On Oct 7, 2013, at 19:25, Jim Reid <j...@rfc1035.com> wrote: > On 7 Oct 2013, at 18:15, Erwan David <er...@rail.eu.org> wrote: > >> Google is really rejecting emails in IPv6 because of a lack of PTR... > > If that's the case, good. Just do The Right Thing and arrange a valid PTR for > the IPv6 address that speaks SMTP. This should be simpler and less hassle > than changing the postfix config. Or adding more workaround to that when > someone finds yet more mail providers who reject connections from addresses > with no reverse DNS. > > SMTP from an address with no reverse DNS is a fairly good indicator of a spam > source. YMMV.
Make sure your ISP supports reverse DNS for IPv6, either by request or by delegating it to you. If you cannot get this sorted yet, I would recommend simply postponing IPv6 rollout for your MX for now, until your ISP finally catches up. We have had valid reverse DNS for the IPv6 address on our outgoing mail server from the start, and we've never run into the limits described in this thread. That said, when we first rolled out IPv6, Google had a problem on their side with SPF checks for IPv6 addresses, which took them a while to resolve. Perhaps these rate limits are another example of something that needs to be fixed or adjusted on their end. Mvg, Joni
