Managing online system definition changes

A request to add an application or to modify the current set of programs, transactions, and database usage need not force a complete system definition and an IMS restart, with possible interruption for the online users. You can examine the request to see if an online change or dynamic resource definition (DRD) process can satisfy the request.

If the request does not involve changes to the IMS network or the use of static terminals as defined in the current IMS system definition, you can use the online change process to make the changes while the IMS system is executing online. Manage the preparation of the IMS system data sets as described under IMS System Data Sets for Online Change in IMS Version 15.3 System Definition. It is also important to assess the impact to the terminal users and the online system operation.