I have currently setup the latest version of postfix in a development environment as a relay server to Exchange on the internal network... all seems to be working like a charm (postfix will only reside on the internal network)



I now have the requirement to setup three different senarios


1) Setup internal clients by ip range ie 10.10.10.0/8 to be able to relay to Postfix for which it will only deliver internally to the exchange server (no outbound messages)

2) Setup internal clients by ip Hostname to be able to relay to Postfix for which it will then deliver via a MCafee Appliance in the DMZ before it passes the message onto clearswift appliance that resides on the DMZ

3) Setup internal clients by ip Hostname to be able to relay to Postfix for which it will only deliver directly to the clearswift appliance in the DMZ


We have multiple zones in our environment simply need some guidance on where to get start and where to look


Any help would be greatly appreciated

Here would be a good start for you: http://www.postfix.org/SMTPD_ACCESS_README.html

Another example:

At this point have decided to remove multiple hops and send the mail to one location