On Fri, Jul 04, 2025 at 07:39:45PM +0200, Dmytro Alieksieiev via Postfix-users
wrote:
> Does anybody know the original reason of why there is no way to adjust
> response code for Alias expansion error (internal loop detected) in Postfix
> settings?
Configuration errors detected by Postfix result in *soft* SMTP error
codes, giving operators who pay attention to their logs a chance to
resolve the error befor the sender gives up and bounces the message.
This is a basic design principle.
>
> Response: host outgoing-node-01.example.com[192.0.2.10] said: 451 4.6.0
> Alias expansion error (in reply to end of DATA command)
>
> From my understanding this is quite permanent configuration error
Only if you (choose to?) ignore problems. Others have an opportunity to
fix them and not lose mail.
> I checked docs as well as src code and as far as I see there is no way to
> adjust it.
By design.
> (double-bounce) works - it checks deliverability up to "RCPT TO:", but alias
> expansion done only at DATA, so there is no way to not accept such email. Is
> there is any reasons why alias expansion not done at RCPT TO? From my view
> it's should be done here.
virtual(5) alias expansion is done in the cleanup(8) server as part of
writing the queue file, this happens after RCPT TO is accepted by
smtpd(8) and handed off to cleanup(8).
> Moving alias expansion to first MTA is possible but it still doesn't solve
> issue in general, as I don't want to answer to external MTA with 451 soft
> fail error in this case.
It seems you want an MTA that is less opinionated about robustness in
the face of problems, ... perhaps Exim could be more to your taste???
Otherwise, I'm afraid you should expect Postfix to continue to softfail
on configuration SNAFUs.
--
Viktor.
_______________________________________________
Postfix-users mailing list -- postfix-users@postfix.org
To unsubscribe send an email to postfix-users-le...@postfix.org
