SMTP over IPv6 : gmail classifying nearly all IPv6 mail as spam since 20140818
matija at serverflow.com
Sun Nov 2 21:38:19 CET 2014
On 11/02/2014 06:55 PM, Darren Pilgrim wrote:
> On 8/22/2014 2:46 AM, Matija Grabnar wrote:
>> So, much as I would LIKE to have reverse IPv6 DNS on my mail servers, in
>> some cases it is just not possible.
> Can you describe those cases? I can't think of any scenarios where
> you'd run a correctly-configured public MX and not have reverse DNS.
Bah - I have a correctly configured public MX on my home network (static
IPv4, static IPv6). It's correctly configured, but I have been as of now
unable to convince my provider to delegate reverse DNS (for IPv6) to my
DNS. They are simply not set up for that. Otherwise, the MX is
completely correctly configured. Under IPv4 it even has a PTR (for the
lone static IPv4 address).
And I've had similar problems ("we are not set up to delegate reverse
DNS for IPV6") with a hosting provider. I had a suggestion on the list
that I should simply rehost my machines, but alas it is not practical,
since the provider was chosen for a bunch of other parameters (bandwidth
cost, hosting cost, etc), with IPv6 connectivity an afterthought.
It is completely possible to have a "correctly configured public MX" and
not have a reverse DNS - unless your definition of "correctly configured
public MX" demands a reverse DNS, but I assume you wouldn't insult both
our intelligences with a "no true scotsman" fallacy of that sort.
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