Business continuity manager support – HP StorageWorks XP Remote Web Console Software User Manual
Page 39
Table 11 TrueCopy for Mainframe Async Suspension Conditions (continued)
TrueCopy for Mainframe Asynchronous
Pairs to be Suspended
Detected by:
Suspension Condition
All TrueCopy for Mainframe
Asynchronous R-VOLs in the consistency
group.
RCU
The RCU could not settle a pending
recordset before the copy pending
timeout group option expired.
All TrueCopy for Mainframe
Asynchronous R-VOLs in the consistency
group.
RCU
The RCU could not communicate with
the MCU before the copy pending
timeout group option expired.
Only the affected R-VOL.
RCU
The RCU could not receive the
recordset successfully due to a
hardware failure.
All TrueCopy for Mainframe
Asynchronous R-VOLs in the group, or
only the affected R-VOL, depending on
the failure type and error level
TrueCopy for Mainframe Asynchronous
pair option.
RCU
The RCU detected a logical error while
selecting the recordset to be settled.
RCU
The RCU could not settle the recordset
due to a hardware failure, a track
condition, or a logical error.
The MCU stores a differential data in the shared memory for each TrueCopy for Mainframe
Asynchronous M-VOL, and the RCU stores a differential data in the shared memory for each
TrueCopy for Mainframe Asynchronous R-VOL. When a TrueCopy for Mainframe Asynchronous
pair is suspended, the tracks which contain the following records are marked in the differential
data as modified (to be copied during the resynchronize pair operation):
•
The recordsets that were created by the MCU but not yet sent to the RCU. After marking these
tracks as modified, the MCU discards these recordsets.
•
The recordsets that were sent to the RCU but not acknowledged by the RCU. The MCU marks
these M-VOL tracks as modified and discards these recordsets. This ensures that recordsets
which are lost during transmission to the RCU are identified and marked.
•
The recordsets that reached the RCU but have not yet been settled. After marking these tracks
as modified, the RCU discards these recordsets.
•
The M-VOL records updated by host-requested write I/Os after the pair was suspended (same
function as for TrueCopy for Mainframe Synchronous pairs). When a suspended TrueCopy
for Mainframe Asynchronous pair is resynchronized, the contents of the RCU's differential
data are sent to the MCU and merged into the MCU's differential data. The MCU then performs
the resync operation according to the merged differential data. This ensures that all tracks
containing recordsets that were discarded are resynchronized at this time.
Business Continuity Manager Support
The HP disk array on which TrueCopy for Mainframe is installed supports Business Continuity
Manager commands. If the host system console issues the Business Continuity Manager commands
to the HP disk array, the TrueCopy for Mainframe pair operations can be performed. The Business
Continuity Manager commands allow you to add pairs, suspend pairs, resynchronize pairs, release
pairs, monitor the pair status, add RCU, and delete RCU.
“SAID Values for the PATH LINK Parameter
(= ports) (FRONT CL1)” (page 41)
and
“SAID Values for the PATH LINK Parameter (= ports) (REAR
give the HP disk array adaptor ID (SAID) values. For further information and
instructions on Business Continuity Manager, see the HP StorageWorks for Business Continuity
Manager User Guide.
Although the same TrueCopy for Mainframe pair operations may be performed by using Business
Continuity Manager or PPRC, Business Continuity Manager and PPRC are independent functions.
Do not use Business Continuity Manager and PPRC for the same pair operation.
Business Continuity Manager Support
39