Autor: Marc Perkel Data: Para: Jack Bailey CC: exim users Asunto: Re: [exim] UCEPROTECT Blacklists and why callouts are abusive
Jack Bailey wrote: >> 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.
>
Exim caches callouts and probably should have some other features to
limit callouts to a specific server so as not to overwhelm them. I don't
know of any Exim servers who have loaded another server because of callouts.
