Re: mail.local NSS awareness (fourth patch)

["Greg A. Woods; Planix, Inc." <woods%planix.ca@localhost>]

On 1-May-08, at 2:52 AM, Emmanuel Dreyfus wrote:
> So my claim that the message was to be silently discarded was wrong. A
> DSN gets generated. I wrongly understood the issue, because when I  
> have
> been confronted to the problem, the DSN went to the original sender,
> which had the same delivery failure, and it was lost.

If the DSN was not deliverable then it should still end up somewhere.   
Any mailer which loses a DSN is losing mail and that should not  
happen.  Some mailers put the failed bounces in an error queue where  
they can be examined manually and retried if necessary.

Ideally the mailer should never accept mail from a return address  
which is known to be, or can be shown to be, invalid; though of course  
it can only go so far with determining the validity of the return  
address without actually delivering a test message to it.  I've made  
sure my mailer logs all such double bounces and then marks the failed  
return addresses as invalid such that they will not be accepted again  
for future transactions without operator intervention.

--
                                        Greg A. Woods; Planix, Inc.
                                        <woods%planix.ca@localhost>