I am currently running a Gentoo machine with Sendmail/MIMEDefang/Spamassassin/Clamav which acts as a front-end mail server to a couple of different mail servers. The main back-end mail server is an Exchange 2003 server and the other is currently a Mac OSX machine running Mailman. I am using a mailertable to direct the different domains (10 domains go to the Exchange server and 1 domain goes to the OSX machine). I am using MIMEDefang's md_check_against_smtp_server feature to verify recipients before they are accepted at the gateway.
I am going to switch to a Debian machine with Postfix/Amavisd/Spamassassin/Clamav as my new front-end mail server to the Exchange server and the OSX machine (I am going to use the old Gentoo machine for mailman once I wipe it and install Debian). 1. Can I use the reject_unverified_recipient feature to get the same functionality as I did with MIMEDefang's md_check_against_smtp_server? I have seen articles about exporting the Exchange users via LDAP and putting them in an access map file on the Postfix server, but I am not a big fan of that. I would prefer to just query the Exchange server directly for valid addresses. 2. Is it possible to only require the reject_unverified_recipient option on certain domains? 3. Do I just set up each domain in a Transport Map file and tell it which server to send the mail to? I also have some e-mail addresses on the Exchange server that I do not want the gateway to accept mail for. That should be pretty easy I can just put them in a recipient check hash file. But, nothing is ever easy, there are a few e-mail addresses that I would like to receive mail for to those restricted Exchange e-mail addresses. And, any mail created from that machine itself would need to be able to send to those restricted Exchange addresses. How can I do that? Thank you for any help you can offer me or guidance on where I can look for answers. Jeff
