Understanding the recovery control data set
The CICS® VR recovery control data set (RCDS) contains essential information for recovering your VSAM spheres.
- CICS® VR ISPF dialog interface default values
- MVS™ log streams
- MVS™ log stream copies
- Registered logical backups
- Change accumulation data sets
- CICS® VR VSAM batch logging
- Shadows
This information is stored in three identical linear VSAM data sets. Three data sets are used to reduce the possibility of data loss. CICS® VR regularly checks to make sure the three data sets are consistent.
- Through the CICS® VR ISPF dialog
- By using the log of logs scan, with CICS® TS
- By using log stream copy, with CICS® TS
- Automatically by CICS® VR, with change accumulation
- Automatically by CICS® VR, with VSAM batch logging
- Automatically by doing a shadow forward recovery
- Automatically when the CICS® VR server address space is active
- Automatically when CICS® VR is notified of a logical backup created for a VSAM data set
- Automatically when CICS® VR is notified of a VSAM backout failure, and recovery or reorganization is requested.
- Log streams
- SAM copies of a log
- Log of logs
- Registered logical backups
Deregistration is triggered by running scan or automatically by the CICS® VR server address space. Once deregistered, CICS® VR automatically reuses the freed space in the RCDS; you never need to manually recover free space. For more information on automatic deregistration, see Understanding CICS VR automatic deregistration.
The RCDS must be allocated to a recover job for batch REDO after images unless the recover being run also specifies the REMOTE keyword.