May 9, 2023 at 4:07 AM, "Gellner, Oliver via mailop" <[email protected]> wrote:
> > If a receiver only accepts emails from sender addressed domains for which MX > or A records exist (such checks are performed by many receiving servers), it > means a sender has to 1. set up a DNS zone and 2. create a MX or A record > within it. No. A DNS zone is not needed at all for sending email. My ex-employer is a Nasdaq listed company, whose business email is with @staff.sina.com.cn. It has MX only, not a zone. $ dig staff.sina.com.cn soa +short $ dig staff.sina.com.cn mx +short 10 staffmx.sina.com.cn. 10 staffmx1.sina.com.cn. Also, my policy in Postfix has setted up to reject messages from unknow_sender_domain, which means if a domain has neither MX nor A, it would be rejected by me. smtpd_sender_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unknown_client_hostname, reject_unknown_sender_domain As you see, Postfix's reject_unknown_sender_domain validates only MX and A, not SOA. regards. -- https://kenpeng.pages.dev/ _______________________________________________ mailop mailing list [email protected] https://list.mailop.org/listinfo/mailop
