Christian R??ner:
> Would it technically possible to have a smtpd_to_lmtp_proxy option
> (or however it could be called), that would receive on smtpd and
> open a connection to its LMTP server, doing cleanup and Co. in
> memory and wait for the result of the LMTP server? If the LMTP
This does not scale. The problem is that you find out if a recipient
is over quota AFTER Postfix has already allocated the maximum amount
of mail server resources.
The scalable way is to make the quota check BEFORE allocating more
mail server resources. As has been suggested many times over the
past 13 years, this means using an SMTPD access map or policy daemon
to block mail for over-quota recipients.
Wietse
