Recoverable resources

In CICS®, a recoverable resource is any resource with recorded recovery information that can be recovered by backout.

The following resources can be made recoverable:
  • CICS files that relate to:
    • VSAM data sets
    • BDAM data sets
  • Data tables (but user-maintained data tables are not recovered after a CICS failure, only after a transaction failure)
  • Coupling facility data tables
  • The CICS system definition (CSD) file
  • Intrapartition transient data destinations
  • Auxiliary temporary storage queues
  • Resource definitions dynamically installed using resource definition online (RDO)

In some environments, a VSAM file managed by CICS file control might need to remain online and open for update for extended periods. You can use a backup manager, such as DFSMSdss, in a separate job under MVS™, to back up a VSAM file at regular intervals while it is open for update by CICS applications. This operation is known as backup-while-open (BWO). Even changes made to the VSAM file while the backup is in progress are recorded.

DFSMSdss is a functional component of DFSMS/MVS, and is the primary data mover. When used with supporting hardware, DFSMSdss also provides a concurrent copy capability. This capability enables you to copy or back up data while that data is being used.

If a data set failure occurs, you can use a backup of the data set and a forward recovery utility, such as CICS VSAM Recovery (CICS VR), to recover the VSAM file.