I have setup Modoboa server in Ubuntu system (static IP) using this link.
Internal emails are working (username@example.com to username2@example.com), but an email from an external provider like Google or Yahoo is not working.
Already set up with A, MX (Google, MailServer), TXT (spf and _dmarc) records, but still emails from external providers are not delivered.
I'm getting this error in /var/log/mail.log
:
(connect to alt4.gmail-smtp-in.l.google.com[209.85.146.27]:25: Connection timed out)
Also, port 25 is open.
I got the updates from the Internet Service Provider. Port 25 is blocked by them.
What is the alternative way to start. (Google, Yahoo mail)