On 2024-03-03 at 14:36:25 UTC-0500 (Sun, 3 Mar 2024 20:36:25 +0100) Marco Moock via mailop <m...@dorfdsl.de> is rumored to have said:
Most server require that the PTR points to a domain name like mail.example.org and that has the corresponding A/AAAA records that point to the IP address.
"Most" is probably an overstatement. Requiring that the PTR result resolves back to the client IP will lose you a small subset of mail from the Microsoft outbounds (a chronically small proportion of which are just wrong) and a whole lot of smaller sources of wanted email.
A common alternative configuration is requiring that an IP have a PTR (equivalent to Postfix's "reject_unknown_reverse_client_hostname") and sometimes people figure out ways to require more (e.g. that the name resolve to something.)
-- Bill Cole b...@scconsult.com or billc...@apache.org (AKA @grumpybozo and many *@billmail.scconsult.com addresses) Not Currently Available For Hire _______________________________________________ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop
