Postfix allows you to specify lists of access restrictions for each stage of the SMTP conversation. smtpd_client_restrictions smtpd_helo_restrictions smtpd_sender_restrictions smtpd_relay_restrictions smtpd_recipient_restrictions smtpd_data_restrictions smtpd_end_of_data_restrictions UCS only use "smtpd_recipient_restrictions". But in some environments there will be a problem that you can't adjust specific restrictions. In this case (Ticket#2017042721000845) an external mail server does "recipient address verification". In combination with restricted mailing lists, the address probes will fail because of our mis-configured sites that reject "MAIL FROM: <>" to this restricted mailing lists. If we could configure the check for the listfilter (check_policy_service unix:private/listfilter) to "smtpd_data_restrictions" there will be no problem for the "recipient address verification" and the "real" mail will successful delivered to the restricted mailing list (if the sender is allowed to).
Is bug 44473 sufficient to fix this issue?
Created attachment 9069 [details] patch für bug
Individual configuration can be done in the main.cf.local, as introduced by bug 44473. Examples may be provided by an SDB article from bug 40377