SMTP on port 26


How can I enable port 26 for SMTP (postfix)?


It should suffice to replace “smtp” with “26” in /etc/postfix/

Be aware though that you won’t be able to generally receive email from the internet if you change port 25 to 26. All regular email servers will always try to deliver mail for you on port 25.

Perhaps I didn’t make my self clear.

I want SMTP on both 25 and 26. Some ISPs block 25 and I need users to have the opportunity to use the alternate/secondary 26 port (not 465 and 587).


You could always just make a copy of the “smtp” line in the file Locutus mentioned, and in that copy, change “smtp” to “26”. Then restart Postfix.


Yup, like Eric said! Though, why not use the Submission port? That’s specifically for that purpose, ie receive mails by local users.


Sorry for the late response.

I have a:
smtp inet n - n - - smtpd -o smtpd_sasl_auth_enable=yes

and a:
smtp unix - - n - - smtp

line in the file. Which one I edit?

You’d duplicate the first one with inet as type.

It works great, thank you guys :slight_smile:

Great to hear, and you’re welcome! :slight_smile: