Autor: Marc Perkel Datum: To: exim users Betreff: Re: [exim] UCEPROTECT Blacklists and why callouts are abusive
David Saez Padros wrote: > Hi !!
>
>
>>> None of this is true for callouts. We are forced to expend server
>>> resources in handling callouts. Our ability to receive our own
>>> email is impaired by other people's use of callout verification.
>>> (How well would your mailserver stand up to receiving four orders
>>> of magnitude more connections per second than it should?)
>>>
>> Verizon did this to me once. A spammer was forging one of my domainnames
>> in a spam run so VZ was issuing 70-100 callouts/second to my server. I
>> had no usable mail service for hours, so I blacklisted their callout
>> farm. Then they blacklisted me for blacklisting their callouts.
>>
>
> this looks like a faulty implementation, i'm sure that this 70-100
> callouts/second to your server where also a problem for Verizon
>
> all of this drives to no place ... wouldn't it be more practical to
> recommend good callout practices ?
> Generally what you want to do is block on the good blacklists, bad HELO,
verify recipient, and other blocking tricks forst and then do sender
verification last. I try to reduce callout traffic as much as I can.
