disable SMTP relay for one domain

[JTRipper]

Hello,

is it possible to block SMTP just for one domain?
We got several domains continuously sending spam using autentication and causing blacklistins of the whole server.

Is there a way to block only SMTP relaying for just one domain/account ?

Thanks in advance,

 

[Amin Taheri]

First I would point you to the postfix config stuff, you will learn a lot looking through these.
http://www.postfix.org/STANDARD_CONFIGURATION_README.html

Secondly, if this user is getting you on blacklists and sending out a bunch of spam then I would just boot them now, save you the grief for the few bucks your getting off them its not worth it.
Third, do not ever let users send mail unauthenticated - its a bad bad practice and really the only people who use or need that are spammers.