1. sudo yum install postfix spamassassin (spamassassin is optional and not covered here)
2. sudo vi /etc/postfix/main.conf
uncomment the following line:

default_privs = nobody

change the following lines

myhostname = sf-lug.com

mydomain = sf-lug.com

myorigin = $mydomain

(make sure smtp listens on all interfaces (eth0, lo0…)

inet_interfaces = all

mydestination = $myhostname, localhost.$mydomain, localhost

(deny mail from other hosts -check me!)

mynetworks_style = host

 mail_spool_directory = /var/spool/mail

3. Change the following in /etc/hosts so mail will come from the right domain (sf-lug.com)

127.0.0.1               sf-lug.com localhost