Using CICS® TS autojournaling

CICS® TS supports the automatic journaling (autojournaling) of file control data to a specified general log stream. Parameters specified in the CICS® definitions of VSAM files determine whether or not autojournaling is to be performed, and the types of operations (add, read, or others) that are recorded.

IBM® recommends that the log records produced by CICS® TS autojournaling must only be used for audit purposes, for the following reasons:
  • When a failure occurs during forward recovery logging, CICS® performs certain actions to prevent loss of data, but these actions are not performed when a failure occurs during autojournaling. Therefore it cannot be guaranteed that a VSAM sphere is completely and correctly recovered from log records produced by CICS® TS autojournaling.
  • During forward recovery logging, CICS® writes specific log records for the VSAM spheres that are eligible for backup-while-open (BWO) processing. These log records are required by CICS® VR to perform a proper restore and forward recovery of VSAM spheres from BWO backups. CICS® does not write these BWO-specific log records during CICS® TS autojournaling.
  • CICS® TS autojournaling does not contain proper RLS support. This means that log records produced by CICS® TS autojournaling cannot be guaranteed to correctly recover a VSAM sphere that was opened and updated using RLS.
Despite the known risks, some users want to use log records produced by CICS® TS autojournaling to forward recover VSAM spheres, because this process has the following advantages over forward recovery logging:
  • It eases the transition from CICS/ESA V4R1 to CICS® TS (because you do not need to update the CICS® file definitions with forward recovery logging information).
  • It eliminates some of the overhead that occurs with forward recovery logging.
With these possible limitations, CICS® VR can forward recover a VSAM sphere from log records produced by CICS® TS autojournaling. However, note again that IBM® recommends using log records produced by CICS® forward recovery logging to recover VSAM spheres. Also, please note the following restrictions when log records produced by CICS® TS autojournaling are used for the forward recovery of VSAM spheres:
  • CICS® VR change accumulation does not support log records produced by CICS® TS autojournaling.
  • CICS® forward recovery logging must not be enabled for the VSAM spheres that you want to forward recover from log records produced by CICS® TS autojournaling. This means that the CICS® VR VSAM batch logger cannot at present be used to log updates made to the same spheres by batch jobs.

The following sections explain the steps required to enable CICS® TS autojournaling for VSAM spheres and to set up CICS® VR to forward recover the spheres from the autojournal log records.