Setting up CICS® VR VSAM batch logging

CICS® VR VSAM batch logging, referred to as batch logging, provides logging of updates made to VSAM data sets by batch jobs. Two types of batch logging are available, forward recovery logging and undo logging.

Forward recovery logging writes an after-image log record to a forward recovery log stream for every update made to the VSAM data set by a batch job. Therefore, if the data set becomes corrupted, CICS® VR forward recovery can be used to recreate the updates made by the batch job.

Undo logging writes a before-image log record to an undo log stream for every update made to the VSAM data set by a batch job. Therefore, if the batch job encounters an abend, CICS® VR batch backout can be used to remove the updates made by the failed batch job or batch job step.

Forward recovery logging, undo logging, or both can be enabled for a VSAM data set. This section explains the tasks required to enable batch logging for your VSAM data sets.

CICS® VR VSAM batch logging requires the following:
  • z/OS 1.12 or later, with all necessary PTFs applied. Refer to Operating environment for details.
  • Activation of the CICS® VR server address space. For more information, see Activating the CICS VR server address space.
  • All VSAM data sets that request batch logging must be SMS-managed.
  • The LOGR Couple Data Set (LOGR policy) must be defined. The LOGR policy includes the following definitions:
    • Log stream definitions
    • Coupling facility list structure definitions, if applicable
    • Data containing the current state of a log stream, for example; whether a log stream is currently connected to the coupling facility structure.
    For more information on the formatting a LOGR couple data set and defining the LOGR policy, see z/OS® MVS™ Setting Up a Sysplex, section "Preparing to Use System Logger Applications".
CICS® VR VSAM batch logging calls the MVS™ system logger to write the log records to the MVS™ log stream. The MVS™ system logger is a component of z/OS®, which provides a programming interface to access records on a log stream. For more information about the MVS™ system logger, see the following publications:
  • z/OS® MVS™ Programming: Assembler Services Guide
  • z/OS® MVS™ Programming: Assembler Services Reference ABE-HSP
  • z/OS® MVS™ Setting Up a Sysplex
The following topics are described in this section:
  • Using CICS® VR VSAM batch logging
  • Enabling CICS® VR VSAM batch logging
  • Setting up the logging environment for CICS® VR VSAM batch logging
  • Detecting batch logging error conditions