Um ein Smarthost mit Postfix zu verwenden müsst ihr lediglich diese Konfiguration in /etc/postfix/main.cf vornehmen.

# specify SMTP relay host
relayhost = [IP des Smarthots]:25
smtp_sasl_auth_enable = yes
# disallow methods that allow anonymous authentication.
smtp_sasl_security_options = noanonymous
# where to find sasl_passwd
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
# Enable STARTTLS encryption
smtp_use_tls = yes


nano /etc/postfix/sasl_passwd
[IP des Smarthosts] Benutzer:geheim


postmap /etc/postfix/sasl_passwd
chown root:root /etc/postfix/sasl_passwd /etc/postfix/sasl_passwd.db
sudo chmod 0600 /etc/postfix/sasl_passwd /etc/postfix/sasl_passwd.db