Question How to change port 25 to 587?

[ice]

Server operating system version

Debian11

Plesk version and microupdate number

18.0.44

Hi.
I have been using Plesk for a long time and I have port 25 open at home and everything works. I recommended my friend Plesk, he started using it, but he has port 25 blocked. So, I go to:
settings - mail server settings - Enable SMTP service on port 587 for all IP addresses - checked.

When I send an email, the logs contain:
206F35C044C: to = <[email protected], relay = none, delay = 2.2, delays = 0.18 / 0.01 / 2/0, dsn = 4.4.1, status = deferred (connect to alt2.gmail-smtp-in.l .google.com [74.125.200.26]: 25: No route to host)

How to permanently change port 25 to another?
Best regards

 

[Maarten.]

Port 587 is used to send an email via the Plesk mail server. It forces you to authenticate before you send an email. Otherwise, everyone could abuse your mail server without authenticating (also called an "open relay").

Port 25 is used by the outside world to deliver emails between mail servers. As port 25 is blocked, Gmail can't deliver the email.

Have a look at this article:

Which SMTP Port Should I Use? Understanding Ports 25, 465, & 587 | Mailgun

Which SMTP port should you use — port 25, port 465, or port 587? Click to learn more about Mailgun's guide to understanding SMTP ports.

www.mailgun.com