Port 25 blocked, change ubuntu mailout to open port

Question

My ISP blocked my port 25 (comcast), so I can't send mailout (via postfix). Can I modify to send mail out on 587 or so? I'm having issues figuring it out correctly.

Solution 1

May be this link will help you: http://www.freebsddiary.org/postfix-transport.php

Solution 2

You can configure Postfix to send mail to port 587 of other servers. The problem is that they won't accept it. 587, the "Message submission" port, is strictly limited to users sending outgoing mail, and always requires authentication; for mail incoming from other servers, only port 25 is used.

Solution 3

You may want to use port 587 as the submission port for SMTP mail rather than 25 (many ISPs block port 25), you will need to edit /etc/postfix/master.cf to uncomment the relevant line for port 587 there.

Comments

[Timofey Stolbov]

It depends on your mail routing scheme. Please show how your postfix configured.

[Admin]

it's the default configuration

[Admin]

If I relay through comcast, does the from come from the comcast acct email? I've got a very large email qty to shoot out to my subscribers.

[Admin]

I set up 587 in the masterc.cf; but for some reason it's still pushing on 25 (i commented out the smtp line for 25)

[Timofey Stolbov]

@Michael I don't know for sure. You can easily test this.