HP XP Racks User Manual
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When P-VOL data is not updated from a host or when the consistency group is in a suspended state, the consistency
time or EXCTG consistency time is not updated, which causes a continual increase in the differential value consistency
delta or EXCTG consistency delta.
C/T TIME MODE
For Continuous Access Journal Z, the P-VOL updates are applied to the S-VOLs some time after
being copied to the restore journal. Therefore, when in the DUPLEX status, the values for the
consistency time and consistency delta differ based upon the setting for C/T TIME MODE.
The C/T TIME MODE setting is used to select whether to use the timestamps for when data is reflected
onto S-VOLs or to use the timestamps for when data is received by the restore journals for the
values set for consistency time and consistency delta. The setting for C/T TIME MODE does not alter
the values of the EXCTG consistency time or the EXCTG consistency delta. The C/T TIME MODE
setting provides equivalent results to SOM (system option mode) 530.
describes the values that can be set for C/T TIME MODE.
Table 3 Values that can be set for C/T TIME MODE
Description
Setting value
The consistency time value and the consistency delta value
are set based on P-VOL updates that have reached the
JOURNAL
R-JNL. The consistency time is more recent when this value
is set than when VOLUME is set.
If a suspension occurs in a 4x4 configuration or because
of particular type of error, data with a value older than
this value is sometimes applied to the S-VOL.
The consistency time value and consistency delta value are
based upon the P-VOL updates that have been applied to
the S-VOLs.
VOLUME
The system option mode (SOM530) is used to determine
the consistency time value and the consistency delta value.
ASIS
For details about system option mode, see the HP XP7
Continuous Access Journal for Mainframe User Guide.
The following figure provides an overview of consistency group and EXCTG values in Continuous
Access Journal Z.
Grouping to simplify volume operations
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