We have an IIS server running windows 2000 with three IPs as a result of consolidating four different web servers into a single box. One of the services provided is a web front end for financial and student records. The back end server is in another county and we have no control over it. There have been several issues but we have eliminated most.
Now we have discovered our server seems to randomly pick one of the three IPs when it makes a request to the other server. Since the other server will only accept requests from a single IP, most transactions fail.
How can we tell our server to make all of its requests from a single IP?
If this is an IIS 101 question, please forgive me. I know next to nothing about IIS and need to fix this immediately.