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

Matija Grabnar matija at
Wed Nov 5 11:12:36 CET 2014

On 11/04/2014 06:01 PM, Doug Barton wrote:
> On 11/4/14 1:43 AM, Matija Grabnar wrote:
>> OK, now I see that we come from fundamentally opposite viewpoints.
>> I'm arguing about what measures it makes sense to use to get good
>> protection while still enabling people to use their residential internet
>> for more than just consumption, while you are determined to block all
>> email originating from residential addresses, regardless of validity or
>> how well the servers are run.
> Right-o! :)  You see, the problem is that even if a tiny percentage of 
> mail is originating from well-run servers in consumer space, the 
> overwhelming majority of it is spam, primarily from infected hosts. So 
> never mind rDNS (which is a very cheap and useful initial test to 
> perform), most ISPs publish indexes of their residential space to 
> allow the larger mail providers to blacklist that space up front.

I remember, some years ago, people making *exactly* the same argument 
for blocking all the mail from Asian countries. I found that a bad 
argument then, I find it a bad argument now.
>> Since our goals are exactly opposite, I don't think we'll ever see
>> eye-to-eye on what steps are appropriate.
> It's fine for you not to agree, as long as you understand the 
> landscape. :)  Several others have already given you the excellent 
> advice to get a cheap VPS and do your thing(s) on a network that is 
> well supported for those things. If you're interested I'm sure we can 
> find you some solid recommendations. Make sure that you find out in 
> advance what address space you'll be on. That way you can check the 
> reputation lists in advance. It would suck to get on a new system only 
> to find that still can't send mail.

I remember the time when the Internet was the place where "the little 
people" (as opposed to big corporations) could experiment and innovate. 
IPv6, with it's no-need-for-dynamic addressing should make that easier, 
not harder. (Provided their provider doesn't block incoming connections 
on a network-wide level).

A person incapable of properly configuring SMTP on their home server 
would be equally incapable of properly configuring a hired VPS server. 
And vice versa, someone capable of properly configuring a VPS server is 
equally capable of configuring a server in their home.

So I argue in favor of examining the mail itself and what can be 
determined of the mail server, and giving less weight to just what 
network it comes from.

Prejudice expends less energy, true, but it tends to false positives. So 
I argue that prejudice, in general, is a bad policy.

> Good luck,
> Doug

More information about the ipv6-ops mailing list