Ajouter les lignes :
smtpd_sasl_path = /etc/postfix/sasl:/usr/lib/sasl2
smtp_use_tls = yes
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
relayhost = smtp.my.network
smtp_sasl_security_options =
Créer le fichier /etc/postfix/sasl_passwd et ajouter les lignes
smtp.my.network monuser:monpassword
Redémarrer postfix
