Assign Technical System to a System 
You assign existing main instances to technical systems, for systems in your system landscape.
You are in the System Landscape Management work center, in the System Administration view.
You are authorized to make settings in the system landscape. For further information, see the SAP Solution Manager security guide in the SAP Service Marketplace under .
Select a system in the system overview.
Click on Technical System Assignment. A dialog box appears.
You get an overview of the main instances in the selected system. To assign a main instance to a technical system, choose a technical system from the value help.
Save your entries.
You have assigned a technical system to a main instance in the system. This assignment is relevant for projects and solutions in the Solution Manager.