If the provider won't or is unable to provide reverse for the IPv6
static address you have, it will be sub-optimal for you to continue to
advertise and/or use the IPv6 address for SMTP.
It's all part of the 'prove it's not a dynamic ip address' and part of
the 'proper reverse DNS provides some level of authority/delegation to
use that ip address for legit SMTP usage'.
Lyle Giese
LCR Computer Services, Inc.
On 11/02/14 14:38, Matija Grabnar wrote:
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.
