[Linux] Configure Sendmail to accept external mail.

[QT_]

By default, sendmail on Red Hat Linux only listens on the local interface. If you want to use your server for mail, you will need to change this.

1. Log in to your server via SSH with your primary user ID and password, then su - to root.

2. Change directory to: /etc/mail.

3. Edit sendmail.mc with your editor of choice (vim, pico, joe, emacs, etc).

Find the following line:

DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')

And add "dnl" to the beginning so it looks like this:

dnl DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')

Now you save the file.

4. Rebuild the sendmail.cf file:

# m4 sendmail.mc > sendmail.cf

5. Restart sendmail:

# service sendmail restart