HP StorageWorks XP Remote Web Console Software User Manual
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Figure 5 Splitting Processing When the Split Command is Issued and there are Volumes in the
Consistency Group in I/O Processing
If the split command (Pairsplit-r or YKSUSPND) is issued to a consistency group of XP Continuous
Access Sychronous pair and if the I/O processing on some volumes in the consistency group has
not finished, the split operation to the TrueCopy for Mainframe volume pair is executed for
maintaining the data consistency after the track processing of the volume that is in I/O processing
and the data transfer to R-VOL have finished.
shows that the data in track 2 is copied to the R-VOL and the data in track 3
becomes differential data because track 2 is used for I/O processing of the volume in the consistency
group when the split command is issued.
Figure 6 Splitting Process when Split Command Issued and Some Volumes in Consistency Group
During I/O Processing (TrueCopy for Mainframe volume)
When I/O processing on a pair in a consistency group (on which the split command is processing)
is required from the server for open system or the host for mainframe system. If splitting processing
on the corresponding pair has not completed, the splitting processing on the corresponding pair
is given priority. After the pair has been split, the I/O demand is accepted. If the suspending
operation caused by a system failure occurred to the pairs in a consistency group, the suspending
operation is performed similarly. Therefore, the data consistency of the pairs in the corresponding
group is maintained. At this time, the "IEA491E" message is displayed (logged) to the host for
mainframe system whenever the pair status changes to the pair suspended-error in the case of
TrueCopy for Mainframe Synchronous pairs.
RAID Manager and Business Continuity Manager provide some options concerning the control of
access to P-VOL/M-VOL and S-VOL/R-VOL from the host after the pair is suspended. These options
can be specified when the pair is suspended.
and
show
whether or not the host can access P-VOL/M-VOL or S-VOL/R-VOL, when each option is specified.
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About XP Continuous Access Operations