Hi, looks like a simple DNS error to me.
In order for mails from @server.cointalk.com to be valid, that domain must exist as A records in DNS. You could whitelist *.cointalk.com in postfix config, but I suggest fixing the DNS. Greets, Ludi -----Ursprüngliche Nachricht----- Von: owner-postfix-us...@postfix.org <owner-postfix-us...@postfix.org> Im Auftrag von Ruben Safir Gesendet: Dienstag, 5. Januar 2021 09:19 An: postfix-users@postfix.org Betreff: Sender address rejected: Domain not found I'm sorry to bother everyone Any clue why this is happening from the cointalk.com domain I am locked out of the forum :) 2021-01-05T03:11:38.999012-05:00 www2 postfix/smtpd[26176]: NOQUEUE: reject: RCPT from 23-111-188-110.static.hvvc.us[23.111.188.110]: 450 4.1.8 <ng...@server.cointalk.com>: Sender address rejected: Domain not found; from=<ng...@server.cointalk.com> to=<faceb...@mrbrklyn.com> proto=ESMTP helo=<server.cointalk.com> www2:~ # grep cointalk /var/log/mail|less www2:~ # dig mx ng...@server.cointalk.com ; <<>> DiG 9.9.2 <<>> mx ng...@server.cointalk.com ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 58851 ;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 4096 ;; QUESTION SECTION: ;nginx\@server.cointalk.com. IN MX ;; AUTHORITY SECTION: cointalk.com. 180 IN SOA ns0.dnsmadeeasy.com. dns.dnsmadeeasy.com. 2008010139 43200 3600 1209600 180 ;; Query time: 321 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) ;; WHEN: Tue Jan 5 03:18:18 2021 ;; MSG SIZE rcvd: 110 -- So many immigrant groups have swept through our town that Brooklyn, like Atlantis, reaches mythological proportions in the mind of the world - RI Safir 1998 http://www.mrbrklyn.com DRM is THEFT - We are the STAKEHOLDERS - RI Safir 2002 http://www.nylxs.com - Leadership Development in Free Software http://www2.mrbrklyn.com/resources - Unpublished Archive http://www.coinhangout.com - coins! http://www.brooklyn-living.com Being so tracked is for FARM ANIMALS and extermination camps, but incompatible with living as a free human being. -RI Safir 2013
