Autor: Marc Perkel Datum: To: Phil Brutsche CC: exim-users Betreff: Re: [exim] Has anyone done this?
ok - maybe it's worth adding a header - let the bayes filter chew on it?
Phil Brutsche wrote:
> There are many, many legitimate mail sources that do not run MTAs on
> their outbound mail hosts:
>
> * Hotmail
> * Nortel Networks
> * Cisco
> * Yahoo
> * Cox Communications
>
> I'm sure there are more than that, I don't feel like digging through my
> mail server logs to find them.
>
> Personally, I wouldn't rely on such a check alone to reject mail - maybe
> in conjunction with white lists and/or greylisting, but that's a
> *strong* "maybe".
>
> But I'm sure you've heard "your server, your rules" before :D
>
> Marc Perkel wrote:
>
>> I had a friend make an interesting suggestion. He said, "Why not
>> check the sending IP to see if it can receive anything on port 25?"
>> The idea being that a spammer might be sending on port 25 but can't
>> receive anying on port 25.
>>
>> Has anyone try this?
>
>