While IMS is running, it records the event information that is necessary to restart the system if a hardware or software failure occurs. The event information is recorded on an online log data set (OLDS).
When an OLDS is filled, or some other event causes IMS to switch from one OLDS to another, it is archived to the system log data set (SLDS). There is a finite number of OLDS data sets, although this number can be dynamically changed, which are pre-allocated and defined to the IMS control region. The OLDS are reused during the duration of the control region. There can be an infinite number of SLDSs, which are created and allocated as needed.
Related Reading: For more information, see Chapter 22, "IMS Logging," on page 367.
IMS Utility Programs
IMS includes many utility programs to help you run, fine tune, and monitor IMS. These utilities help you:
Some of the IMS utilities are discussed in the context of performing
Related Reading: For information about all of the IMS utilities, see:
There are a number of tools and features available with IMS to help in recovery scenarios. This section describes these tools and features.
Extended Recovery Facility (XRF)
Remote Site Recovery (RSR)
Database Recovery Control (DBRC) Facility
Related Reading: For more information, see Chapter 23, "Database Recovery Control (DBRC) Facility," on page 375.
Fast Database Recovery (FDBR)
Related Reading: For more information about FDBR, see "Fast Database Recovery" on page 471.
IMS Database Recovery Facility for z/OS, V2
Related Reading: For more information about this and other IMS tools, see Chapter 26, "IBM IMS Tools," on page 443.