On Mon, Nov 28, 2011 at 20:44, Mișu Moldovan <dumol@...> wrote:
> On Mon, Nov 28, 2011 at 14:04, Pandu Poluan <pandu@...> wrote:
> [snip]
>>
>> I think it's Postfix's README:
>>
>> http://www.postfix.org/SMTPD_PROXY_README.html
>>
>> That said, the above page explicitly warns about the possibility of server
>> deadlock. Since this is meant to be the corporate mail gateway, I prefer the
>> after-queue methods.
>
> Ah, I see... I know that README and it is basically right. However,
> even with after-queue scanning you will run into the same class of
> problems and you'll have to put limits for the number of threads for
> antispam scanning etc.
>
> The main difference, speed-wise, is that with after-queue scanning the
> MTA will accept and queue new mail much faster. But the delivery will
> still be delayed until scanning finishes. In case of a massive flood
> of mails or a malfunction of the filters, both the sender and the
> receiver will be unaware of the delay.
>
> But if you put the limits right in the before-queue antispam scanning,
> there will be no delays that the sender or receiver are unaware of. In
> case of a massive flood of mails, the sender's MTA will keep retrying
> until reaching the limit (eg. 4 hours) when it will inform the sender
> that it cannot deliver and it is still retrying. So the sender will
> know that he/she must try to reach that person using other channels of
> communication.
>

Hmmm... you do have a point.

I'm going to study MIMEDefang.

Rgds,
-- 
FdS Pandu E Poluan
~ IT Optimizer ~

 • LOPSA Member #15248
 • Blog : http://pepoluan.tumblr.com
 • Linked-In : http://id.linkedin.com/in/pepoluan