Creating a Connection Between Embedded Search and TREX/BWA 
To allow SAP NetWeaver Search and Classification (TREX) or SAP NetWeaver Business Warehouse Accelerator (BWA) and the ABAP system to communicate with one another, you must create a connection between them.
You have installed the current SAP NetWeaver enhancement package.
You have installed the current version of SAP NetWeaver Search and Classification (TREX) 7.1 or SAP NetWeaver Business Warehouse Accelerator (BWA) 7.20 on a separate system. After the installation, you have created an RFC connection between the ABAP system for SAP NetWeaver and TREX/BWA.
More information: Connecting TREX with an ABAP Application (RFC Connection)
Log on to the SAP NetWeaver system and launch the Implementation Guide (IMG). Navigate to the node .
When you launching the Customizing activity, transaction SE38 starts.
In the Program field, enter the ESH_ADM_SET_TREX_DESTINATION ABAP report and choose Execute.
Specify the RFC connection to the TREX/BWA server to be used in the RFC destination of TREX parameter and choose Execute.
Assign the SAP_ESH_LOCAL_ADMIN role to the planned administrators for Embedded Search.
More information: Authorizations
Note
If you want to index documents that contain hidden text, note the additional information in SAP Note 604635.