sudo aptitude install postfix libsasl2 ca-certificates libsasl2-modules
relayhost = [smtp.gmail.com]:587 # The google smtp server and the port
smtp_sasl_auth_enable = yes # Enable Authentication,
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd # Where is the authentication information located
smtp_sasl_security_options = noanonymous # According to http://www.postfix.org/SASL_README.html
smtp_tls_CAfile = /etc/postfix/cacert.pem # The certificate file
smtp_use_tls = yes # Use tls
Then create the authentication file at /etc/postfix/sasl_passwd with the following content.
[smtp.gmail.com]:587 username@gmail.com:password
Then,
sudo chmod 400 /etc/postfix/sasl_passwd # The right permission for the file
sudo postmap /etc/postfix/sasl_passwd # let postfix know about the file
cat /etc/ssl/certs/Thawte_Premium_Server_CA.pem | sudo tee -a /etc/postfix/cacert.pem # Installing the certificate created earlier.
This should get you going. reload postfix configuration.
If you get an error like postfix reload failed, make sure no sendmail( sendmail will be uninstalled while installing postfix but older processes won't die and block port 25 which is your local smtp port) or any other running processes which is blocking port 25, kill them and then reload. Should just work, now any mail client like mail() for php or pony for ruby on rails should be able to send email using the gmail address specified in the /etc/postfix/sasl_passwd #resources
