broken_sasl_auth_clients = yes
inet_protocols = ipv4
local_recipient_maps = $virtual_mailbox_maps
mail_owner = postfix
mailbox_command = /usr/local/libexec/dovecot/deliver
mydestination = localhost
mynetworks = 192.0.0.0/8 127.0.0.0/8
mynetworks_style = subnet
relay_domains = pgsql:/usr/local/etc/postfix/pgsql/pgsql_relay_domains.cf
relay_recipient_maps = pgsql:/usr/local/etc/postfix/pgsql/pgsql_virtual_mailbox_maps.cf
setgid_group = maildrop
smtp_tls_note_starttls_offer = yes
smtp_use_tls = yes
smtpd_delay_reject = yes
smtpd_helo_required = yes
smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination
smtpd_sasl_auth_enable = yes
smtpd_sasl_path = /var/run/dovecot/auth-client
smtpd_sasl_security_options = noanonymous
smtpd_sasl_type = dovecot
smtpd_sender_restrictions = permit_sasl_authenticated, permit_mynetworks
smtpd_tls_CAfile = /usr/local/etc/postfix/ssl/smtpd.pem
smtpd_tls_cert_file = /usr/local/etc/postfix/ssl/smtpd.pem
smtpd_tls_key_file = /usr/local/etc/postfix/ssl/smtpd.pem
smtpd_tls_loglevel = 3
smtpd_tls_received_header = yes
smtpd_tls_session_cache_timeout = 3600s
smtpd_use_tls = no
tls_random_source = dev:/dev/urandom
unknown_local_recipient_reject_code = 550
virtual_alias_domains = pgsql:/usr/local/etc/postfix/pgsql/pgsql_virtual_mailbox_domains.cf
virtual_alias_maps = pgsql:/usr/local/etc/postfix/pgsql/pgsql_virtual_alias_maps.cf
virtual_gid_maps = static:1001
virtual_mailbox_base = /home/vmail
virtual_mailbox_domains = example.com
virtual_mailbox_maps = pgsql:/usr/local/etc/postfix/pgsql/pgsql_virtual_mailbox_maps.cf
virtual_minimum_uid = 1001
virtual_transport = dovecot
virtual_uid_maps = static:1001

Dec 25 01:56:51 postfix/smtpd[11184]: NOQUEUE: reject: RCPT from mail-lb0-f174.google.com[209.85.217.174]: 454 4.7.1 <example@example.com>: Relay access denied; from=<someEmail@gmail.com> to=<example@example.com> proto=ESMTP helo=<mail-lb0-f174.google.com>