HP XP P9500 Storage - Manual (Page 51)

8. From the P-VOL Fence Level list, select the fence level for the new P-VOL(s). The fence level
determines the conditions under which the primary system rejects write operations to the P-VOL.
For an explanation of the options, see
“Change fence level” (page 54) .
9. In the Initial Copy list, select one of the following:
•
Entire Volume: to create the Continuous Access Synchronous pair relationship and copy
the data from primary to secondary volumes immediately. (Default)
•
None: to create the Continuous Access Synchronous pair relationship but copy no data
from primary to secondary volumes. You must ensure that data in the P-VOL and S-VOL
are identical when selecting None.
10. Copy Pace: enter the maximum number of tracks to be copied during the initial copy. Default
is 15.
•
Between 1-5 is slow, and is used to lessen impact to host I/O.
•
Between 5-10 is a medium pace.
•
Between 11-15 is a fast pace. Host I/O performance can be lowered.
11. From the Priority list, specify the scheduling order for the initial copy operation. The default
value is 32 and 1 to 256 can be specified.
For performing more initial copy operations than the setting value of the Maximum Initial Copy
Activities set on the System Option dialog box, the scheduling order (Priority) can be set for
the initial copy operations to be performed.
The Priority is determined within the range of the number of initial copy operations performed
at the same time. Therefore, until the first initial copy operations complying with the order of
the Priority are completed, the additionally specified initial copy operations are not started.
If a time-out error occurs during the Paircreate operation, the copy operation may not be
executed correctly in the order specified in the Priority field. A time-out error may be caused
by the CU configuration or a data path error. Review the error, release the pair with the error,
and then retry the Paircreate operation.
12. From the Difference Management list, select the method for managing differential data. With
Auto, either Cylinder or Track is used by the system depending on the basic size of the logical
unit (LU). Default is Auto. For more information, see
“Managing differential data” (page 21) .
This option cannot be changed after a pair is created.
13. Click Set.
14. You can review these settings in the Preview pane on the Pair Operation window.
•
To modify a setting, right-click the list item and select Modify from the menu.
•
To delete an item, right-click and click Delete.
15. When satisfied, click Apply.
If the operation does not start normally, an error code displays in the Error Code column in the
Preview list. To display an error message, select the LU, right-click, and select Error Detail.
Split pairs
You can split a pair, which suspends data copying to the S-VOL. The following takes place when
a pair is split:
•
I/O writes from the host continue to the P-VOL, but stops to the S-VOL.
•
Any current update copy operation completes to the S-VOL, ensuring data consistency to the
point of the split operation.
•
Pair status changes to PSUS.
•
The primary system records the updated tracks to the P-VOL that occur after the split as
differential data. This data is copied to the S-VOL when the pair is resynchronized.
Split pairs 51