You must perform this step at initial installation and at migration.
The OAM Installation Verification Program (CBRSAMIV) verifies that OAM object support is successfully installed and operational. This program activates the OSREQ macro, and allows dummy objects to be tested by having the storage administrator perform OSREQ functions against them without having to perform an explicit OSREQ ACCESS to connect the macro to OAM, or without having to perform an OSREQ UNACCESS to disconnect the macro. Run this job (see OAM installation verification program and OAMUTIL for a sample of this job), and perform some OSREQ functions as a test to insure the product is successfully installed.