When network conditions prevent a RAS server from obtaining an appropriate IP address from its' preferred DHCP server, it may obtain one from another network.
To workaround this behavior, use one of the following 3 methods:
Method 11. Open the RRAS snap-in.
2. Right-click the server and press Properties.
3. Select the IP tab.
4. Select Static address pool and press Add.
5. Enter the static pool range.