On Sat, Jan 02, 2021 at 09:51:48PM -0700, Bob Proulx wrote: > Brett Lymn wrote: > > Bob Proulx wrote: > > > SPF identifies authorized IP addresses for domains in the message > > > envelope. Therefore the reverse DNS pointer record does not matter in > > > > I used to be postmaster for a large organisation and know for a fact that > > even if > > you have SPF and DKIM set up properly there are still places on the > > internet that > > will insist on the forward/reverse check and reject the mail if the > > addresses don't > > match. I can't give specific examples, I cannot remember, but they exist > > so keep an > > eye out for rejected mails. > > I wish you had not quoted the SPF bit when talking about forward > reverse DNS checks but had instead quoted the bit where I talked about > forward reverse DNS. Because it leads me to believe that you think it > is somehow related to SPF checks instead. And as far as I know the > forward reverse DNS issue is not in any way related to SPF. >
No I am not confused about what SPF does. I was picking up on what you said: "Therefore the reverse DNS pointer record does not matter in" that is true in the context of SPF but as I said not everyone does that, there are sites out there that will do the forward/reverse validation. > > Right. There are sites that will require this. They will tend to be > the smaller sites that set something up in 2003 and are still running > the same configuration now. Mostly running MS Windows Server 2000 or > some such platform. It is generally not going to be a default action > for new sites. I don't think any of the large mailbox providers > require it. > It really doesnt matter why they are doing it, just that they do. If you are trying to communicate with these people then it becomes a real issue if they are rejecting your emails. It is common enough that we were getting complaints at $WORK about rejected emails when our reverse lookups were broken. -- Brett Lymn -- Sent from my NetBSD device. "We are were wolves", "You mean werewolves?", "No we were wolves, now we are something else entirely", "Oh"
