How does “sendmail” send mails to any domain name?

umanga asked:

I noticed that one of our servers (running Ubuntu) can send mails to any domain (yahoo.com ,gmail.com) using simple “sendmail” command.

But I cannot figure out how to configure similar setup in a new server. I cannot see any files such as “/etc/mail/sendmail.cf” in the first server.

How does this work ? Does it use some other SMTP server to do actual mail delivery? Where can I find these settings?

My answer:


It’s probably running postfix, not sendmail. The sendmail command is provided mainly for cross-compatibility.

You’ll find the configuration files for postfix in /etc/postfix and documentation at the Postfix homepage.


View the full question and answer on Server Fault.

Creative Commons License
This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.