Fast DB Recovery region in DBCTL

The Fast DB Recovery region is a separate IMS control region that monitors an IMS, detects failure, and recovers any IMS-owned database resources that are locked by the failed IMS, making them available for other IMS systems without having to wait for the next full restart.

For database resources that are not IMS owned, such as Db2 for z/OS®, the Fast DB Recovery region provides the optional ESAF Indoubt Notification exit routine (DFSFIDN0) for this purpose.

The Fast DB Recovery region is executed by the cataloged procedure supplied by IMS system definition. You must start the Fast DB Recovery region after you start the IMS that it tracks.

To enable a DBCTL subsystem for Fast DB Recovery, you specify the FDRMBR parameter in the DBC procedure. The FDRMBR parameter defines the DBCTL system as Fast DB Recovery-capable.