In /etc/postfix/main.cf hinzufügen relayhost = smtp.server.com smtp_sasl_auth_enable = yes smtp_sasl_password_maps = hash:/etc/postfix/smtp_auth smtp_sasl_security_options = noanonymous Datei /etc/postfix/smtp_auth hinzufügen: smtp.server.com senduser:supersecret Erstelle lookup-table /etc/postfix/smtp_auth.db : postmap /etc/postfix/smtp_auth Postfix reloaden: sudo service postfix reload