After Replication Server and Adaptive Server are installed on your system, you must enable a RepAgent for each database the Replication Server manage.
In addition, if Replication Server is the source site for any route, you must enable RepAgent for the Replication Server RSSD.
In some scenarios for setting up RepAgent, you use rs_init, in other scenarios you must use command line options:
If you install a new Replication Server or add a new database, use rs_init to set up RepAgent. This process enables RepAgent, set default parameters, and start RepAgent. See the Replication Server Configuration Guide for your platform for information about rs_init.
To change an existing replicate database to a primary database, you must use command line options.
By default, the Adaptive Server RepAgent consists of a single thread that scans the primary database log, generates LTL, and sends the LTL to Replication Server. With multithreaded RepAgent, the scanning and sending activities are performed by separate threads. You can then configure multithreaded RepAgent to use additional paths from the primary database to support Multi-Path Replication™.
See Replication Server Administration Guide Volume 2 > Performance Tuning > Multi-Path Replication.