1. My test environment does not contain an Exchange server, but my live environment does. I will be leaving the exchange server behind the backend ISA firewall. I don't believe that I will have any trouble sending mail out, but I am wondering if I will have any issues receiving mail as it will have to come through both firewalls. I am not sure if it matters, but my backend firewall will be an SBS2003 box.
2. On the internal interface of my front end firewall, I have been using my ISP's dns servers, is this correct? Do I require a DNS server listed there at all, since ISA should route to the ISP through the external interface anyway.
3. The last time I created the environment, I had to enter the backend firewalls internal range of addresses to successfully communicate with the network behind the backend firewall. For instance, I placed a web server in my DMZ, but when creating the publishing rule on the front end server, I could not resolve the machine name of the web server, because the front end could not communicate with the DNS server, which is behind the backend firewall. After writing it out, it does kinda make sense, but I don't remember doing this in prior configurations. Just wondering if that is the right way to do it or not.