HP XP P9500 Storage - Manual (Page 33)

System option modes
HP provides system option modes to tailor customer requirements on the P9500 system. System
option modes are used with Continuous Access Journal for the following:
•
2DC configuration using Continuous Access Journal and Continuous Access Synchronous
•
Delta Resync configuration using Continuous Access Journal and Continuous Access
Synchronous
•
Configuring split options for mirrors
Table 7 System option modes
Description Mode
Mode 448 ON: If the SVP detects a blocked path, the SVP assumes that an error
occurred, and then immediately splits (suspends) the mirror. 448
Mode 448 OFF: If the SVP detects a blocked path and the path does not recover within
the specified period of time, the SVP assumes that an error occurred, and then splits
(suspends) the mirror.
Note: The mode 448 setting is available only when mode 449 is set to OFF.
Mode 449 ON: The SVP does not detect blocked paths. 449
Mode 449 OFF: The SVP detects blocked paths and monitors the time until the mirrors
get split (suspended).
Allows you to perform the initial copy operation of the Continuous Access Synchronous
pair for the suspended Continuous Access Journal pair. 474
Use the script file in which the following operations are described:
Initial copy operation of the Continuous Access Journal pair (None) -> Suspend the
Continuous Access Journal pair -> Initial copy operation of the Continuous Access
Synchronous pair -> Delete the Continuous Access Synchronous pair -> Resynchronize
the Continuous Access Journal pair. The performance of the initial copy processing of
the Continuous Access Journal pair can be improved by issuing the command from
RAID Manager.
Mode 474 ON: The performance of the initial copy processing of the Continuous Access
Journal pair can be improved by issuing the command from RAID Manager.
Mode 474 OFF: Normal operations are performed.
To create a Continuous Access Journal pair for delta resync operation in the 3DC
multitarget configuration, set this mode to ON. 506
Mode 506 ON: The delta resync operation is performed if there are no update I/Os.
Mode 506 OFF: The copy processing of all data is performed if there is no update
I/Os.
In the configuration where multiple MCUs share an RCU (Continuous Access Journal
Mx1 configuration), the mirror resynchronization or delta resync operation may fail 593
due to SSB=EB9D. SSB=EB9D is output as SSB log when the parameter of the
communication command is not saved in the shared memory. To reduce the number of
multiprocessing of the communication command issued from MCU to RCU for the status
transition of each pair, set this mode to ON. By setting this mode to ON, you can
prevent mirror resynchronization or delta resync operation from failing.
Mode 593 ON: The multiprocessing of the communication command issued from MCU
to RCU is up to 128 pairs per DKC.
Mode 593 OFF: The multiprocessing of the communication command issued from MCU
to RCU is up to 1024 pairs per DKC.
The host I/O response might decrease while the Continuous Access Journal pair is
resynchronized. To suppress increase in the MP utilization rate by the differential bitmap
retrieval processing when resynchronizing the pair, set this mode to ON. 760
Mode 760 ON: Decrease in host I/O response during the Continuous Access Journal
resync operation is reduced.
Guidelines for preparing systems for Continuous Access Journal 33