HP StorageWorks XP Remote Web Console Software - Manual (Page 133)

Hitachi TrueCopy for z/OS user guide 133
NOTE: If the RCU is not able to complete these actions within the copy pending timeout setting,
the RCU will discontinue the original suspend request and forcibly suspend the affected volume
pairs. Thus, you can use the copy pending timeout parameter to limit the amount of time it takes to
complete the suspend/drain operation.
Purge. The MCU will change the TC390A pair status from suspending to suspended as soon as the
RCU accepts the suspend operation. The MCU and RCU discard any pending recordsets and mark
the cylinders that contain discarded recordsets as modified in the M-VOL and R-VOL bitmap,
respectively. When the pair is resumed, the M-VOL and R-VOL bitmaps will be merged at the MCU,
and all cylinders marked as modified will be copied to the R-VOL.
NOTE: If the MCU does not receive acknowledgement of the suspend operation from the RCU
within the copy pending timeout setting, the MCU will forcibly suspend all affected pairs and report
an IEA491E host console message.
To suspend one or more TC390 volume pairs:
1. Connect to the MCU (or RCU) of the volume pair(s) to be suspended. You do not need to vary the
M-VOL(s) offline. To use the R-VOL write enable option, you must connect to the MCU and select the
M-VOL of the pair.
2. From the CU Number tree on the TrueCopy main window, select the number of the correct CU image.
3. From the Volume list on the TrueCopy main window, select the TC390 volume pair(s) that you want to
suspend. Select either TC390 Synchronous or TC390A pairs, but not both. The pair status must be
Duplex.
4. Right-click to display the pop-up menu and click Suspend Pair. The Suspend Pair window is displayed.
5. From the Suspend Pair window, select the options for the pair(s), and then click Set to close the Suspend
Pair window and set the parameters. The list changes to the Pair Settings Parameter list (Suspend Pair).
You can modify the options as needed (see ” Modifying parameters and omitting selected volumes ” on
page 122). Verify that the Suspend Pair options for each pair are correct. The suspend kind option
(R-VOL or M-VOL failure) and fence level pair option determine whether the M-VOL will accept write
I/O operations after the pair is split.
CAUTION: If you need to split a pair and the M-VOL is required for system operation, do not use
the M-VOL Failure suspend kind option. Make sure to use the R-VOL suspend kind option so that the
M-VOL continues accepting I/Os.
6. To execute the Suspend Pair requests quickly, select the Use Time-Saving Mode check box above the
Pair Settings Parameter list (Suspend Pair).
7. Click Apply on the TrueCopy main window to split the specified pair(s). For the TC390 Synchronous
pairs, the MCU will complete all M-VOL write operations in progress and the associated update copy
operations at the R-VOL before splitting the pair so that the pair is synchronized at the time of Suspend
Pair.
8. From the TrueCopy main window, verify that the TC390 pair(s) is/are displayed correctly (Suspended
status) in the Volume list. The Resume Pair command (see ” Resuming TrueCopy volume pairs (Resume
Pair) ” on page 134) resumes suspended TC390 volume pair(s).
CAUTION: If a timeout error occurs after clicking the Use Time-Saving Mode option, confirm on the
TrueCopy main window for which volumes the Suspend Pair operation could not be performed.
Deselect the Use Time-Saving Mode option for the failed volume and retry the Suspend Pair
operation.