I currently have Exchange 2000, but am in the process of moving to Exchange 2k3. My current setup is as followed:
In DMZ I have a Linux box accepting my mail and forwarding into my internal network to Exchange. Then Exchange sends out of a different IP address (than the Linux box). I am not really sure why it is setup this way but when I got here that is what was working.
I want to add a FE Exchange 2003 server and upgrade my current Exchange 2000 box to 2003. I have read the MS technotes, but I wanted to see if anyone had any tips, tricks or ideas to get this done. As of right now I am thinking about leaving the incoming mail so that it comes from the Linux box (not broke don't fix it) and then add a FE to my DMZ so users can use, OWA and OMA. I have gone back and forth with the idea of using MS ISA 2004 but have never used it and really don't understand what it is going to do different from my current firewall. Any help would be greatly appreciated.