Postfix en tant que relay

aptitude install postfix

Configuez le en tant que "internet with smarthost". Dans SMTP Relay Host, entrez l'hostname:port que vous souhaitez utiliser comme smtp sortant.

echo "login@domain password" > /etc/postfix/smarthost_passwd
chown root:root /etc/postfix/smarthost_passwd
chmod 600 /etc/postfix/smarthost_passwd
postmap /etc/postfix/smarthost_passwd

configuration de postfix :

relayhost = hostname:port
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/smarthost_passwd
smtp_sasl_security_options = noanonymous

/etc/init.d/postfix restart