Issue with two namespaces

[smtest]

I have two different installs one for internal namespace and the other for external namespace. Install looks like this:
Application server 1: 8.1 internal (with content manager) and 8.1 external (using 8.1 content manager)
Application server 2: 8.1 internal (with content manager) and 8.1 external (using 8.1 content manager)
i am noticing different urls in the report search path. If i am logged in as internal user, i see the report url points sometimes internally and sometimes externally. If i bring down the external piece then only it points to internal url. I have checked the gateway url of both internal and external install. They look fine. Please advice