Ok i have spent about a week on this so far and only gone around in a full circle:

Im attempting to develop a Postfix box for spam filters. The thing is I dont want spam assassin or any other real filters, i need to develop post fix to accept all mail and then filter the main based on valid mail boxs house on a exchanger server. (this means postfix would relay those messages to the exchanger server.) while all the other message are put into a catch all mailbox on the local postfix server.

Does anyone one have any ideas to help me with this?

Hello Drifter,


Can you please reformulate your problem as (at least for my self) I don't really understand what you are trying to achieve.

1. What do you want to filter? Mail body, subject, From, To, the headers or doing a content filtering.

2. What is the relation with your exchange server?

As far as I know Postfix is a "pure" MTA server:

I'm lost from here:

I need to develop post fix to accept all mail and then filter the main based on valid mail boxs house on a exchanger server (by this do you mean doing a recipient check? in this case you can use the build in fonction LDAP check). (this means postfix would relay those messages to the exchanger server.) while all the other message are put into a catch all mailbox on the local postfix server.(if I understand correctly you want to keep all emails which was addressed to a no existent email address... if this is what you want to do, can you explain me why you want to do so? To see if there is an other (better) solution.)

Thanks,
Angel.

You could use procmail in conjunction with postfix.

Postfix fetches mail and procmail processes it; sorting valid mail to the addressees and other mail to a catchall folder.

Procmail includes example setup files in /usr/share/doc/packages/procmail/examples/.

You probably need some help with unknown recipients (ie unknown users). See http://www.postfix.org/rewrite.html

Other than that, you need some way of determining valid users on the exchange server for mail you want to forward. Can you use ldap for that?