On Mon, Oct 25, 2021 at 09:35:35AM +0000, Vincent Pelletier wrote: > I would rather postfix just stop sending emails altogether in such > case, than send them from an unexpected ip: a delay is preferable to > me to uncertainty as to how the emails were processed by recipient > SMTPs. > > Is there something else I should set so postfix stops falling back to > no binding ?
No such setting is presently available in Postfix: https://github.com/vdukhovni/postfix/blob/master/postfix/src/smtp/smtp_connect.c#L231-L234 Instead, monitor your system configuration for absence of IP addresses expected by the Postfix configuration, and add any transports whose IP address is not configured to "defer_transports" (if not already present) and execute "postfix reload". You can collect the list of configured addresses via: ( postconf -xh smtp_bind_address postconf -Ph '*/unix/smtp_bind_address' ) | sort -u The warnings in the logs should also be noticed. -- Viktor.