On 17 Jun 2015, at 3:00, Michael Peter wrote:
Hi,
I understand that postfix send bounces or failed delivered
notifications
using empty sender.
As does every MTA which in compliance with the SMTP standards of the
past >25 years.
See https://tools.ietf.org/html/rfc5321 and its linked ancestors for
details.
But does postfix accept empty sender emails during the MAIL FROM
command
during the SMTP conversation?
Yes, unless it is misconfigured to reject the null (empty) sender.
because i think that postfix needs a valid
email address ?
No, it needs a valid SMTP return path value, which can either be an
email address OR null.
if postfix reject empty sender emails during receiving of emails, so
how
come bounces and failed delivered notices are received from other
email
servers ?
The condition of your 'if' clause is not normally met.
The reason i am asking for that in order to block some spam attacks on
our
email mail server that using empty email senders
Do not block mail simply because of a null sender, as that will
eliminate all valid email failure notices generated elsewhere. Find
another way.
