OT: Sendmail REJECT or DISCARD preference

[Scott Silva]

on 3-28-2008 2:58 PM Peter Farrow spake the following:
> Richard Siddall wrote:
>> Steve Freegard wrote:
>>> Peter Farrow wrote:
>>>> If you reject,  and its spoofed you'll get it back anyway, so you 
>>>> end up receiving and then storing it in the postmaster address, it 
>>>> is always best to discard in this scenario...or even worse bouncing 
>>>> it again
>>>
>>> Huh? - explain this a bit better as it doesn't make sense to me.
>>>
>>
>> I believe you can get in this situation if you get a lot of e-mail 
>> forwarded to your servers on behalf of your clients by an intermediate 
>> ISP.  If you then reject the e-mail at SMTP time the intermediate ISP 
>> tries to relay the reject as a bounce and you then get backscatter.
>>
>> Quietly discarding the spam gets rid of the backscatter, along with 
>> any false positives.
>>
>> Unfortunately, there's no easy way of pushing your rejection criteria 
>> out to the intermediate ISPs so they can avoid accepting e-mail you 
>> won't accept from them.
>>
>> Regards,
>>
>>     Richard Siddall
> Precisely,
> If you're running a mail server that is an intermediate scanner for 
> hundreds of domains prior to final delivery at the clients servers, a 
> REJECT notice that you send back which is to a false address will quite 
> correctly come back to the postmaster box of the REJECT machine.  In 
> this way a discard is MUCH better as you don't bother to report the 
> failure to the intermediate MTA because it was junk anyway.  With a 
> discard you silently bin it saving everyones time, diskspace and bandwidth.
> 
> This has to be considered in the context of a machine that scans mail 
> for lots of domains for delivery to lots of clients disparate servers.  
> In this context you'll find that a DISCARD is far better...
> 
> 
> 
> 
That I agree with. But that is a special case.
But wouldn't dumping the double bounces stop this?


-- 
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You hope everybody uses it, and
you notice quickly if they don't!!!!

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