# reject_unknown_sender_domain: Reject return paths with invalid domains.
# * reject_unknown_sender_domain: Reject return paths with invalid domains.
# reject_rhsbl_sender: Reject return paths that use blacklisted domains.
# * reject_rhsbl_sender: Reject return paths that use blacklisted domains.
#
# * permit_sasl_authenticated: Authenticated users (i.e. on port 587) can skip further checks.
# permit_sasl_authenticated: Authenticated users (i.e. on port 587) can skip further checks.
# * permit_mynetworks: Mail that originates locally can skip further checks.
# permit_mynetworks: Mail that originates locally can skip further checks.
# * reject_rbl_client: Reject connections from IP addresses blacklisted in zen.spamhaus.org
# reject_rbl_client: Reject connections from IP addresses blacklisted in zen.spamhaus.org
# * reject_unlisted_recipient: Although Postfix will reject mail to unknown recipients, it's nicer to reject such mail ahead of greylisting rather than after.
# reject_unlisted_recipient: Although Postfix will reject mail to unknown recipients, it's nicer to reject such mail ahead of greylisting rather than after.
# * check_policy_service: Apply greylisting using postgrey.
# check_policy_service: Apply greylisting using postgrey.
#
#
# Notes:
# Notes:
# permit_dnswl_client can pass through mail from whitelisted IP addresses, which would be good to put before greylisting
# permit_dnswl_client can pass through mail from whitelisted IP addresses, which would be good to put before greylisting