Troubleshoot Mail Server Using DigitalOcean Tutorial?

I followed the tutorial to try and get a mail server running at home. I’m on Comcast, however, who blocks port 25, so I added this into the config in order to use the Comcast relay. This is the only thing I did differently.

relayhost = []:587
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_sasl_security_options =

I then made a file /etc/postfix/sasl_passwd and put:        COMCASTUSERNAME:COMCASTPASSWORD

As far as I’m aware, this should work, but when I put in the details in Gmail it says it can’t reach the server. As for Gmail, I have:

SMTP Server:
Port: 25 [Since I'm using the relay, I'm assuming my end should be configured to 587 and outside should be pointed to 25, although I did try 587 on Gmail, too, to no avail.]
Username: [I have 3 test accounts]
Password: [That account's password]
And I have "Secured connection using TLS" bubbled.

How should I go about troubleshooting this? Thanks.


Submit an answer
You can type!ref in this text area to quickly search our full set of tutorials, documentation & marketplace offerings and insert the link!

These answers are provided by our Community. If you find them useful, show some love by clicking the heart. If you run into issues leave a comment, or add your own answer to help others.


I’ve not personally tried this with Comcast, so I can’t verify that this indeed works, though I’d check:

From there, if you run in to any issues, reply back and we can try to troubleshoot from there :-).