IBM OS/390 User Manual

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No matter what utility is used to perform the backup and recovery of a catalog,
the process isn
t complete until the catalog is resynchronized with the data sets
as they currently exist. Between the time the catalog was backed up and
restored, data sets have been deleted and defined and the catalog has to be
updated to reflect these changes. These changes to catalogs, or catalog events,
are recorded in SMF records. The SMF record types for catalog events are:
61 - When records are added to the BCS during DEFINE
65 - When records are deleted or updated in the BCS
66 - When changes are made to the BCS during ALTER processing
With these records, the information for catalog re-synchonization is available, but
there is still a need for a facility that can use this information to update the
catalog quickly. Using these records without a tool designed to process them is
possible, but is time consuming and laborious.
There are products available such as the 
Integrated Catalog Facility Recovery
Utility or ICFRU - (5798-DXQ) that provide this capability. Combined with a
regular program of catalog diagnostics and backups, proper recording, dumping
and tracking of data from SMF, it is possible to shorten the time of a catalog
outage.
31.9.1.3 Checking a VSAM KSDS for Structural Errors
AMS provides the EXAMINE command which can be used to analyze and report
on the structural integrity of the index and data components of VSAM KSDS
clusters and the basic catalog structure (BCS) of an ICF catalog.
EXAMINE INDEXTEST examines the index component of a KSDS by
cross-checking vertical and horizontal pointers contained within the index
control intervals.
EXAMINE DATATEST evaluates the data component of a KSDS by
sequentially reading all data control intervals, including free space control
intervals.
Messages describing errors or inconsistencies are generated during EXAMINE
processing as that condition is detected. For more information concerning the
EXAMINE command, refer to 
DFSMS/MVS Access Methods Services for ICF,
SC26-4906.
31.9.2 DFSMShsm
DFSMShsm has its own set of diagnostic aids that can be used by a system
programmer when diagnosing problems. The 
DFSMS/MVS DFSMShsm Diagnosis
Reference, LY27-9608 provides information about DFSMShsm control blocks and
data areas used during diagnostic and maintenance procedures. The 
DFSMShsm
Diagnosis Guide, LY27-9607 provides instructions for diagnosing errors such as
building keyword strings.
The 
DFSMS/MVS Managing Data Availability, SC26-4928 provides information
about disaster prevention and the recovery of DFSMShsm data based on real
experiences.
Chapter 31. Diagnosing System Problems
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