Hi, Working on a project that I need some advice on. I need to build out a Postfix server that will act as a smart host of sorts for several internal mail domains (each domain on a different server). The server will need to:
- Relay mail directly between all of the internal mail domains (there are 5) without routing traffic to the Internet. - Relay mail destined for remote domains that originated from any of the 5 internal domains to edge Postfix systems. - When relaying to the edge Postfix systems, route to the appropriate edge system based on the sending domain. For example, take internal domains a.com - e.com. When a.com sends an email to anyone in domains b.com - e.com, the smart host should simply route that traffic back to the internal mail server for that domain. However, if a.comis sending email to yahoo.com, google.com, etc, then the smart host should forward that message to a.com's edge Postfix system so the traffic will exit to the Internet on a.com's WAN connection. This system will not be affected by inbound email traffic from remote domains (edge systems handle this). I've done some reading on multiple Postfix instances as a possible way of doing this but looking for someone to tell me if I'm looking in the right direction before I jump into this. Thanks as always...
