>> One minor comment: I would not even offer AUTH on port 25. > >I don’t. I offer opportunistic TLS on port 25 for SMTPd. All mail >submission have to be on port 587.
You do. valo@uschi:~ $ telnet mail.covisp.net 25 Trying 65.121.55.42... Connected to mail.covisp.net. Escape character is '^]'. 220-mail.covisp.net ESTMP -- Please wait 220 mail.covisp.net ESMTP Postfix 3.0.3 ehlo test.local.host 250-mail.covisp.net 250-PIPELINING 250-SIZE 26214400 250-ETRN 250-STARTTLS 250-AUTH PLAIN LOGIN 250-AUTH=PLAIN LOGIN 250-ENHANCEDSTATUSCODES 250-8BITMIME 250 DSN quit 221 2.0.0 Bye Connection closed by foreign host. See the two lines offering auth on port 25. You should disable auth on port 25. -- Christian
