0

I installed Plesk Obsidian in Ubuntu 18.04.3. Trying to send messages through the port 587 I'm getting the following error:

postfix/smtp[116387]: connect to alt1.gmail-smtp-in.l.google.com[209.85.233.27]:25: Connection timed out

It seems that postfix is still trying to send emails through the port 25, but I already changed my configuration to force postfix to send emails through the port 587 using sumbission.

in /etc/postfix/main.cf I have:

smtpd_tls_security_level=may
inet_protocols = ipv4

and in /etc/postfix/master.cf

submission inet n       -       n       -       -       smtpd
  -o smtpd_tls_security_level=encrypt

in Postfix

Enable SMTP service on port 587 on all IP addresses: checked
  • SPF, DMARC & DKIM records are enabled

What could be causing that postfix still uses the port 25 for outgoing emails?

denoise
  • 53
  • 6

1 Answers1

2

Port 587 is one of the regular submission ports: Clients may choose to speak to your mail server over that port when they want your server to relay their mail to its intended recipient.

SMTP traffic between mail servers should go over the standard SMTP port; 25.

Mikael H
  • 5,031
  • 2
  • 9
  • 18