Fast Path Restart Control Facility is a standard OS job step that precedes the control region step in the IMS job stream or started-task JCL procedure. It assesses the current state of the IMS system and performs any required recovery activities.
If IMS is started with AUTO=YES, Fast Path Restart Control Facility performs the following functions:
Ensures that MSDB integrity can be maintained
If MSDB integrity will be compromised by an AUTO=YES restart, RCF will automatically take corrective action.
Ensures that the RDS is usable by IMS
Ensures that the set of MSDB checkpoint and RDS data sets used by the surveillance system are present and usable in an IMS-XRF environment
When IMS is started with AUTO=NO, Fast Path Restart Control Facility determines if the IMS system is a partner in an IMS-XRF active complex. If so, and this is a restart for the surveillance system, a standard restart of that system will be performed. If DBRC indicates the surveillance system is active, DBRC is notified it is no longer active.
If the restart is for a non-XRF system or for the active partner system in an IMS-XRF Complex, Fast Path Restart Control Facility automatically performs the following tasks:
Invokes DFSULTR0 to close the last OLDS, if required
Invokes DBRC to indicate IMS abnormally terminated, if required
This removes the necessity to specify OVERRIDE in the IMS restart command.
Deletes, reallocates and restores the MSDBCP n data set from the most optimal source (the other MSDBCP n data set, MSDBDUMP, or a back-up data set) if an MSDB checkpoint data set is flagged as unusable
Invokes DBFDBDR0 to create an up-to-date MSDBINIT data set
If IMS terminated normally, an Unload is performed.
If IMS terminated abnormally, the RECONs are interrogated to determine the log data sets needed, and DBFDBDR0 is invoked to perform a RECOVER function.
Selects the most optimal IMS restart command or validates a user-entered restart command and passes it to the IMS control region
Optionally, invokes the BMC Software Fast Path Recovery Utility (FRU) product to recover all DEDBs, and schedules any required full-function database backouts