Alamgir Shamim:
> Hi,
>
> We have an ISP. We have lots of users. They use our smtp server to
> send mail. Very often we are facing a problem. Sometimes huge unwanted
> mail comes from our users to smtp server who are basically behind nat
> IP and make our smtp server's IP listed in many black list sites like
> SORBS and others. As a result googel, yahoo, hotmail and many more
> site stop receiving mail from our server. How to stop this problem. I
> know this is happen due to kind of worm and others things. But what I
> have to do so that my smtp don't receive those mail and won't get
> black listed.
in addition to other suggestions, rate limit your customers
so that they cannot send unlimited amounts of spam (with postfwd,
policyd, and the like).
Wietse
