I'm having problem setting up my ISA Server and is hoping that someone here can help me out.
Here's my scenario. My ISA Server has 3 NIC.
NIC #1 (192.168.1.2) is connected to my local network (192.168.1.1-192.168.1.254). This is the main network used
NIC #2 (auto) is connected to the ASDL modem (auto dial-up)
NIC #3 (10.35.116.1) is connected to local network #2 (10.35.116.1-10.35.116.254). The router (10.35.116.254) connects to another sites in the organisation (10.0.0.0-10.255.255.255.254). They are not using any ISA Server.
There is no problem accessing the internet from the configuration I set up. To access the sites from 10.0.0.0 to 10.255.255.254, I created a static route using the "Routing and Remote Access".
Recently, because of the internet usage behaviour of the employees, I decided to block certain application from accessing the internet by using the Firewall Client and remove the Gateway setting for all the clients in the local network (Previously, it is set to 192.168.1.2 which is the ISA Server). Because of this, all the clients are unable to access the sites from 10.0.0.0 to 10.255.255.254 anymore.
This is a recognized issue. The problem is that the Firewall client gets its autoconfiguration settings from the ISA firewall and the Firewall clients on the 10. network are trying to connect to the 192. interface, which won't work.
What you can do is enter two wpad entries in DNS and configure the DNS server to use netmask ordering. In that way, the 10. network clients will get the address of the ISA firewall on the 10. network, and the 192. clients will get the address of the ISA firewall on the 192. network.