Appreciate the clarification everybody, thanks
This is really a great group.
On Fri, Nov 21, 2008 at 7:42 AM, Ian Eiloart <iane@???> wrote:
>
>
> --On 20 November 2008 17:50:03 -0500 Rick Duval <rick@???> wrote:
>
>> But my server gets thousands of messages to non-existent local_parts
>> and some spammers send them all from some poor guys address (I know
>> I've been on the victim side of that where someone is spamming and
>> using my address in the from header).
>>
>> I'm not only concerned that I'll be flooding that server with rejected
>> emails but also that my server could end up blacklisted because of the
>> potential flood of replies generated.
>
> Note that rejecting a message at SMTP time (using "deny" in an ACL, for
> example) is different from accepting it and then generating a bounce
> message. If you reject a message, then it is the responsibility of the
> sending server to generate any bounce message. Spammers don't bother.
>
> Your "deny" isn't generating the bounce. The sending MTA is generating the
> bounce. If it's a false positive, then that's a good thing because the
> original sender needs to know.
>
>> Rick
>>
>> On Thu, Nov 20, 2008 at 5:44 PM, Kjetil Torgrim Homme
>> <kjetilho@???> wrote:
>>>
>>> On Thu, 2008-11-20 at 17:24 -0500, Rick Duval wrote:
>>>>
>>>> I now have a lookup that accepts emails only for addresses that are in
>>>> the database.
>>>>
>>>> accept condition = ${lookup mysql{SELECT count(*) from addresses \
>>>> WHERE active AND domain='${quote_mysql:$domain}'
>>>> \ AND local_part='${quote_mysql:$local_part}'}}
>>>>
>>>> deny
>>>>
>>>> It works great but I don't want to contribute to backscatter by
>>>> sending denial messages back to the sender everytime an address is
>>>> rejected. Right now it sends out and email like:
>>>>
>>>> SMTP error from remote mail server after RCPT TO:<bob@???>:
>>>> host duvals.ca [74.51.38.171]: 550 5.1.1 <bob@???>:
>>>> Recipient address rejected: User unknown in virtual alias table
>>>>
>>>> Can I turn that off and just not have it reply at all?
>>>
>>> well, you can blackhole the message, but your current method is the
>>> recommended way of setting it up. if someone mistypes an address, say
>>> "bpb@???", you will typically want him to know about it so that he
>>> can resend it using the correct address.
>>>
>>> you won't be contributing to backscatter unless someone forwards e-mail
>>> to you -- and typoes in forwarding targets should definitely be
>>> reported.
>>>
>>> it's a bit different if your denial is due to a SpamAssassin score or
>>> something like that -- then the forwarding system may have more lax spam
>>> filtering than your system, but it's the forwarding's system which will
>>> be spreading backscatter. even here, it's not really your fault.
>>>
>>> --
>>> regards, | Redpill _
>>> Kjetil T. Homme | Linpro (_)
>>>
>>>
>>> --
>>> This message has been scanned for
>>> viruses and dangerous content by
>>> Accurate Anti-Spam Technologies
>>> and is believed to be clean.
>>>
>
>
>
> --
> Ian Eiloart
> IT Services, University of Sussex
> x3148
>
> --
> This message has been scanned for
> viruses and dangerous content by Accurate Anti-Spam Technologies
> and is believed to be clean.
>
>
