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

[Bjørn Mork]

Darren Pilgrim <list_ipv6-ops at bluerosetech.com> writes:
> On 11/2/2014 12:38 PM, Matija Grabnar wrote:
>
>> 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.
>
> I've had providers tell me that as well, then add that they can set
> the reverse DNS upon request.  If they can't do either, run away from
> them very fast--they just made it very clear they don't have a good
> design.

I am willing to agree as long as we're talking about hosting providers.

But I have been following this thread with great interest from the
retail ISP point of view.  I do hope we can all agree that "set reverse
DNS upon request" isn't a workable solution for any large scale retail
provider.  Running a mail server on a retail access is just never going
to be a supported configuration.  But some users will still do it, and
they should of course be allowed to do so.

But if this is going to require reverse DNS, then we have a problem.
Because, after a bit back and forth discussing different reverse DNS
options like scripted dummies or fully automatic self-service, we
decided to drop reverse DNS for retail IPv6 accesses.  It's just not
worth the effort. Scripted names provide absolutely zilch value over the
IPv6 address itself.  And the fully automatic self-service will have a
few failure scenarios causing it to cost a bit of customer service.  And
also some development resources, and we have some really lazy
programmers ;-)

So that's the conclusion for now at least, until there is some demand
for reverse DNS for IPv6. And I cannot imagine we're the only ISP
arriving there.

Where does this leave anyone requiring reverse DNS?  Are you
intentionally blocking mail servers runnning on retail access lines?  Do
you really believe it would help you in any way if you got a dummy
reverse name (of course with a matching forward too)?  Because
realistically, that is the only viable solution I see.  Even with a self
service reverse DNS in place, there will be enough users not knowing how
to enable it but still setting up a mail server.  So the scripted names
are necessary as a "backup solution".

It just seems so pointless.  The dummy names will be longer than the
address and will contain the exact same information.



Bjørn