OT: Sendmail REJECT or DISCARD preference

[Greg Matthews]

Peter Farrow wrote:
> Matt Kettler wrote:
>> Peter Farrow wrote:
>>> Matt Kettler wrote:
>>>> Peter Farrow wrote:
>>>>
>>>>>> Steve.
>>>>> 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
>>>>>
>>>>
>>>> Stop confusing REJECT with post delivery bouncing :) See my other 
>>>> post in this thread.
>>> I am talking about sendmail access file entries at the MTA level.... 
>>> nothing else...my point is the general notice supplied in the REJECT 
>>> directive often ends up coming back round...I've seen it many times..
>>
>> That's exactly what I'm talking about. I've got several such entries, 
>> and I've never seen any of them come back. ever.
>>
>> There's something seriously wrong with your mailserver if this is 
>> happening.
> This is how it works:
> 
> Someone sends a spoofed spam email to one of my clients the other side 
> of my mailscanner, but they get the address wrong.
> 
> The mailer daemon on the client server rejects the email, (I am the 
> postmaster for my clients Linux server) with user unknown,
> 
> -- But the address is spoofed so it goes back to the wrong person (back 
> scatter), The mail system rejects the back scatter for various reasons 
> (user known mailbox full etc etc etc) so this bounce comes back to the 
> postmaster of the client machine which goes to my postmaster mailbox.

is this a troll? The mail is /rejected/ so it doesnt "go back" to 
anyone. You are talking about /bouncing/ a message and therefore 
composing a DSN with the wrong recipient address. A /REJECT/ stops the 
SMTP transaction dead. Any DSN, if required, is generated by the third 
party MTA.

G

> 
> If I simply DISCARD the email at the mailscanner the process is stopped 
> completely.
> 
> If the mailer daemon REJECTS the message on the mailscanner or the 
> client server,  I get it in the postmaster mailbox as per the reason 
> above because I am also the postmaster there as well...
> 
> So DISCARD is the best way forward.
> 


-- 
Greg Matthews           01491 692445
Head of UNIX/Linux, iTSS Wallingford

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