Click to See Complete Forum and Search --> : Need inbound smtp preprocessor


dccj
09-12-2004, 02:47 PM
Hi!

I need to build a box to preprocess incoming email for an Exchange Server. All I need to it to do is to check if the recipient is on a list, forward it if it is, return an NDR if it isn't. The problem is that the gets thousands of spam emails everyday for recipients that aren't valid. But due to the nature of the business, an NDR needs to be sent in case it is from a legitimate customer who typed in the name wrong. The load on the Exchange server is large enough that if I could remove this part of it, it would be able to do it's job.

The OS flavor isn't important. Something small would be ideal, since it will probably end up on an older machine. It needs to read the valid recipient list from a file. And it needs to either forward the email to a local server if the recipient is valid, or generate an NDR if it isn't. It won't store any emails (no local mailboxes).

What I'm looking for is some pointers on what to use (OS and mail server) and perhaps some pointers on configuring the indicated mail server. If this was already answered somewhere, then a link to that would be great, too!

TIA!

Darryl

fatTrav
09-12-2004, 05:24 PM
a G4L search on "preprocess incoming email for an Exchange Server" returned some stuff about procmail.

The procmail and formail mail processing package can be used to create mail-servers, mailing lists, sort your incoming mail into separate folders/files (real convenient when subscribing to one or more mailing lists or for prioritising your mail), preprocess your mail, start any programs upon mail arrival (e.g. to generate different chimes on your workstation for different types of mail) or selectively forward certain incoming mail automatically to someone.

http://freshmeat.net/projects/procmail/

some other information from G4L

Setup sendmail on your firewall to accept connections from any outside host for those domains that are on internal network's servers.. This would also allow you to preprocess your messages for viruses, spam, content, etc etc on the firewall, without letting it get to your Exchange server where it could cause harm.

so sendmail might be an option too http://freshmeat.net/projects/sendmail/

There should be plenty of stuff out there (books, articles, tutorials) to help get you started. Post back with any questions/comments/etc

dccj
09-13-2004, 05:01 PM
Perfect! This should get me well into it.

Thanks!