Chapter 7. Recording Error Or Statistical Information; Using Erep Reports; Using Error Recovery Procedures (Erp); Using Ims/Vs Logging - IBM 3480 User Reference

Chapter 7. Recording Error or Statistical Information
Using EREP Reports
Some of the maintenance of the 3480 subsystem relies on the records of
errors and statistical information recorded by the processor. Editing,
printing, and system exception reports are included in EREP.
The error records (OBR records) and statistics records (MDR records) in
SYSl.LOGREC contain the 32 sense bytes that the 3480 control unit sends
to the processor. An error code is included in the sense byte information to
aid the service representative in locating the cause of the unit check. MDR
and OBR records have the same format for full function and 3420
compatibility modes. Error records from different systems can be combined
in the EREP system exception reports.
Using Error Recovery Procedures (ERP)
Error recovery procedures (ERPs) support the new sense byte structure of
the 3480. The format of the error messages has been changed slightly.
With the 3480, most of the tape error recovery sequences are initiated by
the control unit. For this reason, and because the control unit provides an
error symptom code, ERP programs are simplified.
Using IMS/VS Logging
IMS/VS has not changed any code for the 3480 but you might want to use
tape-write-immediate mode (DCB
=
OPTCD
=
W) for the log tape. (You
should carefully evaluate the effect of this on performance.) You can
continue to place log data on unbuffered tape drives.
IMS/VS Release 1.3 replaces the log tape with a disk log data set. The 3480
is an ideal device for archiving the 1MS disk log.
Chapter 7. Recording Error or Statistical Information
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