Postfix is an advanced mail server, MTA (mail transport agent). Postfix attempts to be fast, easy to administer, and secure. The outside has a definite Sendmail-ish flavor, but the inside is completely different. Funtoo is providing postfix as default MTA. The main change in funtoo's default postfix configuration is that it is running using unix sockets instead listening on IP address.
Unix sockets allow for greater security and speed when running services that use postfix on the same server as postfix. If you prefer to listen to IP addresses, or your application doesn't support listening on UNIX sockets, editing master.cf should do the trick:
# /etc/postfix/master.cf: # # Postfix master process configuration file. For details on the format # of the file, see the master(5) manual page (command: "man 5 master" or # on-line: http://www.postfix.org/master.5.html). # # Do not forget to execute "postfix reload" after editing this file. # # ========================================================================== # service type private unpriv chroot wakeup maxproc command + args # (yes) (yes) (no) (never) (100) # ========================================================================== #smtp unix n - y - - smtpd smtp inet n - n - 1 smtpd #smtpd pass - - n - - smtpd #dnsblog unix - - n - 0 dnsblog #tlsproxy unix - - n - 0 tlsproxy #submission inet n - n - - smtpd
The above configuration shows that the "smtp unix" line is commented out, disabling listening on sockets. Instead, the line "smtp inet" is uncommented which tells postfix to listen on IP addresses. After editing the file reload the configuration:
root # postfix reload
After that, check that postfix is listening on a port (port 25 by default):
root # netstat -tlpn tcp 0 0 184.108.40.206:25 0.0.0.0:* LISTEN 1099/master tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 1099/master
Depending on your configuration, additional steps might be required, but this should be enough to get simple applications started.