saslauthd needs to be configured first.
Then, to configure postfix to use that for SMTP AUTH add:
/etc/postfix/sasl/smtpd.confcontaining:
pwcheck_method: saslauthd mech_list: PLAIN LOGINIn /etc/postfix/main.cf make sure you have "permit_sasl_authenticated" somewhere in the restrictions before the hard reject. Also make sure the last four lines listed here are somewhere in main.cf.
smtpd_recipient_restrictions = reject_invalid_hostname, reject_unknown_sender_domain, reject_unknown_recipient_domain, permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination, (...) smtpd_sasl_auth_enable = yes smtpd_sasl_security_options = noanonymous smtpd_sasl_local_domain = broken_sasl_auth_clients = yes