I think you are trying to relay all outbound mail through an external mailserver using submission (port 587). I assume there's some additional configuration options I need to postfix? I do not have ufw enabled right now so that is probably not the problem.
I've tried editing /etc/postfix/master.cf and uncommenting this line: smtpd pass - y - smtpdīut I'm still getting timeout errors indicating that it's not using 587.
#SET UP MAIL FORWARD IN SPECTRUM MAIL UPDATE#
How can I update my Postfix installation so that it uses port 587 AND is compatible with the protocols of the server above? (encryption not needed/required unless it's already supported - don't believe TLS is on this) I have confirmed I can telnet to port 587 on my destination server: # telnet 587ĮHLO 220 ESMTP Sendmail 8.14.7/8.14.7 Mon, 18:16:08Ģ Hello hostname, pleased to meet youĢ50-AUTH GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN PLAIN (I'm basically using the sendmail command from the shell to send status reports from this server) Linux myhost 4.4.0-119-generic #143-Ubuntu SMP Mon Apr 2 16:08: x86_64 x86_64 x86_64 GNU/LinuxĪs a result, my outgoing mail transactions are timing out because (I suspect) the default Postfix configuration is using port 25. The Cable ISP is filtering all port 25 (smtp) traffic.
I'm configuring a backup server on a local network that has a cable connection.