Re: postfix for 2 domains on 1 vps 1 ip

[Brett Lymn <blymn%internode.on.net@localhost>]

On Fri, Jan 01, 2021 at 04:50:16PM -0700, Bob Proulx wrote:
> 
> SPF identifies authorized IP addresses for domains in the message
> envelope.  Therefore the reverse DNS pointer record does not matter in
> this.  The hostname does not matter.  Only the IP address as indicated
> through a DNS response.  This is an anti-forgery protection.  This has
> been a defacto standard requirement for all SMTP host sites for some
> years now.  Must have valid SPF records.  However I do know of small
> low activity sites that still do not implement this and squeeze by
> depending upon the nebulous value of the sending host's "IP reputation
> score".
> 

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.

-- 
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"