General migration considerations

Start of changeRCDS migration to CICS® VR V4R3 from CICS VR V4R2 is not required. However, when migrating to CICS VR V4R3 from CICS VR V4R1 or an earlier CICS VR version, you must take precautions to avoid losing data if you encounter a problem during migration. End of change

Therefore, you might want to consider performing the following steps before migrating:

Start of changeYou 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 V4R3 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.End of change

Start of changeThe steps required to migrate to CICS VR V4R3 differ if you are migrating from a release earlier than CICS VR V4R2 or from another forward recovery product. The next two topics list the steps required to migrate to CICS VR V4R3.End of change

Start of changeIf you are using automated recovery you are recommended to update your PLT to add program DWWSFCBF; see Automated Recovery and Reorganization for more information. End of change