IBM System Storage DS3000, Programming Manual

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The command in this example creates a remote mirror in which the primary logical drive is named
Jan_04_Account on the local storage subsystem. The secondary logical drive is named Jan_04_Account_B
on the remote storage subsystem that is named Tabor. The names used in this example are similar, but
that is not a requirement for the logical drive names in a remote-mirror pair. In this example, the remote
storage subsystem has a password that you must enter when making any change to the storage
subsystem configuration. Creating a remote-mirror pair is a significant change to a storage subsystem
configuration. Setting the write mode to
synchronous
and the synchronization priority to
highest
means
that host write requests are written to the primary logical drive and then immediately copied to the
secondary logical drive. These actions help to make sure that the data on the secondary logical drive is as
accurate a copy of the data on the primary logical drive as possible. The highest synchronization priority
does, however, use more system resources, which can reduce system performance.
This example shows how to use the command in a script file:
create remoteMirror primary=”Jan_04_Account”
secondary=”Jan_04_Account_B” remoteStorageSubsystemName=”Tabor”
remotePassword=”jdw2ga05” syncPriority=highest
writeMode=synchronous;
After you have created a remote mirror, you can see the progress of data synchronization between the
primary logical drive and the secondary logical drive by running the
show remoteMirror
synchronizationProgress
command. This command shows the progress as a percentage of data
synchronization that has completed.
Changing Enhanced Remote Mirroring Settings
The
set remoteMirror
command lets you change the property settings for a remote mirror pair. Use this
command to change these property settings:
v
The logical drive role (either primary or secondary)
v
The synchronization priority
v
The write order
v
The write mode
You can apply the changes to one or several remote mirror pairs by using this command. Use the
primary logical drive name to identify the remote mirror pairs for which you are changing the properties.
This example shows how to use the
set remoteMirror
command:
c:\...\...\client>smcli 123.45.67.89 -c “set remoteMirror
localLogicalDrive [Jan_04_Account] syncPriority=medium writeOrder=notpreserved
writeMode=asynchronous;”
This example shows how to use the command in a script file:
set remoteMirror localLogicalDrive [Jan_04_Account]
syncPriority=medium writeOrder=notpreserved
writeMode=asynchronous;
Suspending and Resuming a Mirror Relationship
Use the
suspend remoteMirror
command to stop data transfer between a primary logical drive and a
secondary logical drive in a mirror relationship without disabling the mirror relationship. Suspending a
mirror relationship lets you control when the data on the primary logical drive and data on the
secondary logical drive are synchronized. Suspending a mirror relationship helps to reduce any
performance impact to the host application that might occur while any changed data on the primary
logical drive is copied to the secondary logical drive. Suspending a mirror relationship is particularly
useful when you want to run a backup of the data on the secondary logical drive.
Chapter 8. About Enhanced Remote Mirroring premium feature
8-9