IBM System Storage DS3000, Programming Manual

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Parameter Description
autoResync
The settings for automatic resynchronization between
the primary logical drives and the secondary logical
drives of a remote-mirror pair. This parameter has these
values:
v enabled
– Automatic resynchronization is turned on.
You do not need to do anything further to
resynchronize the primary logical drive and the
secondary logical drive.
v disabled – Automatic resynchronization is turned
off. To resynchronize the primary logical drives and
the secondary logical drive, you must run the
resume
remoteMirror
command.
writeOrder
This parameter defines write order for data
transmission between the primary logical drive and the
secondary logical drive. Valid values are
preserved
or
notPreserved
.
writeMode
This parameter defines how the primary logical drive
writes to the secondary logical drive. Valid values are
synchronous
or
asynchronous
.
Notes
When you use this command, you can specify one or more of the optional parameters.
Synchronization priority defines the amount of system resources that are used to synchronize the data
between the primary logical drives and the secondary logical drives of a mirror relationship. If you select
the highest priority level, the data synchronization uses the most system resources to perform the full
synchronization, which decreases the performance for host data transfers.
The writeOrder parameter applies only to Enhanced Global Mirrors and makes them become part of a
consistency group. Setting the writeOrder parameter to preserved causes the remote-mirror pair to
transmit data from the primary logical drive to the secondary logical drive in the same order as the host
writes to the primary logical drive. In the event of a transmission link failure, the data is buffered until a
full synchronization can occur. This action can require additional system overhead to maintain the
buffered data, which slows operations. Setting the
writeOrder
parameter to
notPreserved
frees the system
from having to maintain data in a buffer, but it requires forcing a full synchronization to make sure that
the secondary logical drive has the same data as the primary logical drive.
Set Session
This command defines how you want the current script engine session to run. For the purpose of this
command a session is the duration for the running of the commands. This command does not
permanently set the parameters for the storage subsystem.
Syntax
set session errorAction=(stop | continue)
password=”
storageSubsystemPassword ”
performanceMonitorInterval= intervalValue
performanceMonitorIterations= iterationValue
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IBM System Storage DS3000, DS4000, and DS5000: Command Line Interface and Script Commands Programming Guide