When migrating to CICS® VR
V5R1 from an earlier CICS VR version, you must take
precautions to avoid losing data if you encounter a problem during
migration.
You are strongly recommended to perform migration during a time when no VSAM spheres are being updated. Also, remember that different levels of CICS VR can run concurrently and independently of each other, if they are using different recovery control data sets (RCDSs). Therefore, you can install and test CICS VR V5R1 while you continue to use the previous CICS VR release until you verify that migration has completed successfully. You can activate only one CICS VR address space for each MVS™ image.
The steps required to migrate to CICS VR
V5R1 differ if you are migrating from an earlier release or from another
forward recovery product. The next two topics list the steps required
to migrate to CICS VR V5R1.
If you are using automated recovery you are recommended to update your PLT to add program DWWSFCBF; see Automated Recovery and Reorganization for more information.