<[hidden email]>: delivery via mx-ha02.web.de[184.108.40.206]:25: 250 Requested
mail action okay, completed: id=1N0YD0-1hUYlq3qCq-00wNxk
But when mail is send to some other foreign postfix servers, the foreign mailserver sends DSN.
How can we specifiy, that only "our" postfix server sends DSN. Reason is, we have custom bounce messages and would
like to only present our users our custom DSN text.
> i would like that postfix always sends DSN, when requested by client and
> mail got forwarded to next-hop / final destination.
Postfix implements a published RFC, and according to that RFC,
Postfix will send a 'relayed' DSN if:
1 - The sender requested DSN notification.
2 - The next-hop MTA does not announce DSN support, or you turn off
DSN support (smtp_discard_ehlo_keywords = dsn, silent-discard).
Additionally, you can tweak the SMTP conversation with
smtpd_command_filter, smtp_reply_filter, and smtp_delivery_status_filter.
There are examples in the documentation of those parameters.