smtpd_relay_restrictions = permit_mynetworks defer_unauth_destination
# What domains to receive mail for: names of local server.
-mydestination = plomlompom.com, localhost
+mydestination = HOSTNAME, localhost
# What clients to relay mail from: only local server.
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128