This is part of the larger task of customizing your z/OS® environment.
WebSphere® Event Broker for z/OS uses Resource Recovery Service (RRS) to coordinate changes to WebSphere MQ and DB2® resources. Ensure it is configured and active on your system, because your broker cannot connect to DB2 unless RRS is active.
Refer to the following manuals for detailed information about RRS: z/OS V1R5.0 MVS Setting Up a Sysplex and z/OS V1R5.0 MVS Programming: Resource Recovery SA22-7616.