comcast ipv6 PTR

Tue Oct 15 16:37:32 UTC 2013

On 10/15/13 10:20 AM, Bjørn Mork wrote:
> In any case: All of you should expect legitimate, technical brilliant
> users attempting to connect to your SMTP servers from IPv6 addresses
> with no PTR records. This is not going to go away.  You are of course
> free to refuse those connections, but personally I find a that rather
> arrogant and pretty stupid decision.  The existence of a PTR record is
> one of many factors to consider for your spam filter.  There never has
> been any reason to make it an absolute requirement, and I am pretty sure
> the score needs to be lowered with IPv6.

Or, as an alternative, actually use the SPF records that multiple big 
companies keep telling people to make sure they have.

I have my SPF records set to allow my IPv6 and IPv4 senders, why are 
they ignoring that and going just for an outright reject on inbound ipv6 
mail?

At least, if its a defer, it has the chance to bounce over to one of my 
backup mail servers that doesn't have IPv6 (or in one case, has a mail 
server out of my directly assigned from ARIN /48 with working rdns).

-- 
Brielle Bruns
The Summit Open Source Development Group
http://www.sosdg.org    /     http://www.ahbl.org