HP StorageWorks XP Remote Web Console Software - Manual (Page 103)

•
CTG: Consistency group used for pair created (Asynchronous pairs only).
•
ErrLvl: Error level, Group or LU. When a failure occurs, pairs in the same group or in an LU
are suspended (Asynchronous pairs only).
XP Continuous Access initial copy and pair options of the Paircreate pane
XP Continuous Access initial copy and pair options specify the fence level, initial copy parameters,
and asynchronous parameters. Initial copy and pair options are selected on the Paircreate pane.
While the initial copy operation is in progress, the initial copy options cannot be changed unless
you delete (pairsplit-S) and then restart (paircreate) the pair. After the initial copy operation is
complete, you can only change XP Continuous Access pair options (Fence Level and Error Level).
Fence Level (XP Continuous Access Synchronous only)
Fence Level: Conditions under which the MCU rejects write operations to the P-VOL, which is known
as “fencing.” This option is very important for disaster recovery planning.
•
Never: The P-VOL is never fenced. If the XP Continuous Access volume pair is split or suspended,
write operations to the P-VOL are accepted.
•
Data: The P-VOL is fenced when the MCU cannot successfully execute an update copy operation
for any reason.
•
Status: The P-VOL is fenced only if the MCU cannot change the S-VOL status to suspended
when an update copy operation fails. If the MCU changes the S-VOL status to suspended,
subsequent write operations to the P-VOL are accepted, and the MCU tracks all P-VOL updates
while the pair is suspended.
Initial Copy parameters
Initial Copy: Initial copy mode for new pairs. The default is Entire Volume.
•
Entire Volume: The initial copy operation copies all cylinders on the P-VOL (except diagnostic
and unassigned alternate tracks) to the S-VOL.
•
No Copy: The initial copy operation is not performed. The MCU performs update copy
operations as needed.
CAUTION: Ensure that the P-VOL and S-VOL are already identical when using this setting.
Initial Copy Pace: Maximum number of tracks (1-15) that can be copied at one time by the XP
Continuous Access initial copy operation before the MCU accepts another host request for that
P-VOL. A high setting (for example, 15 tracks) speeds up the initial copy operation, but may affect
the disk array's I/O performance if the P-VOL experiences high write I/O activity. A lower setting
(for example, 3 tracks) slows down the initial copy operation to minimize impact on the disk array's
I/O performance.
Priority: Order in which initial copy operations are performed if the number of requested initial
copy operations is greater than the maximum initial copy activity setting on the RCU Option pane
(see
Registering RCUs (Add RCU) ). The highest priority is 1, and the lowest priority is 256 (current
default = 32). Use the XP Continuous Access initial copy priority option to spread initial copy
operations across disk array groups and disk array domains (ACP pairs) to reduce initial copy
time and host I/O contention.
Creating XP Continuous Access volume pairs (Paircreate) 103