Network Merging

I have a task of joining two school buildings (High School & Elementrary) via fiber optic approx. a 1.5 miles apart. Each building has two servers; one server for administration applications, and one for students. The H/S also has the proxy for internet access which runs Linux, all other servers are running NetWare 5.
The H/S admin server can not see the proxy without logging off and logging on to the student server.
How do I set it up so either admin server can access the proxy with usersswitching between servers, but keep the students from seeing the admin servers?