IBM System Storage DS3000, Programming Manual

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example
"amg:001"
. The double quotation marks also must be used if the Enhanced Global Mirror Group
name is only a number, as in this example
"001"
. Using double quotation marks when not needed does
not prevent the command from running successfully. If you have any doubts about the Enhanced Global
Mirror Group name, use the double quotation marks inside the square brackets.
This example shows how to use the command in a script file:
suspend enhancedGlobalMirrorGroup ["amg_001"];
The mirror relationship remains suspended until you use the resume enhancedGlobalMirrorGroup
command to restart synchronization activities. This command restarts data transfers between a primary
logical drive and a secondary logical drive in a mirror relationship after the mirror has been suspended
or unsynchronized.
This example shows the
resume enhancedGlobalMirrorGroup
command:
c:\...\smX\client>smcli 123.45.67.88 123.45.67.89
-c “resume enhancedGlobalMirrorGroup ["amg_001"];”
This example shows how to use the command in a script file:
resume enhancedGlobalMirrorGroup ["amg_001"];
Manually resynchronizing logical drives in an Enhanced Global Mirror
Group
Manually resynchronizing the logical drives in an Enhanced Global Mirror Group immediately
resynchronizes all of the mirror relationships within the Enhanced Global Mirror Group. You cannot
perform this operation if one of these conditions exists:
v
The Enhanced Global Mirror Group has failed because any dependent component of the mirror
configuration is in a
Failed
state.
v
The Enhanced Global Mirror Group is in a
Suspended
state.
The manual resynchronization request must be issued to the primary Enhanced Global Mirror Group.
You can run a manual resynchronization on an Enhanced Global Mirror Group that is configured with a
periodic synchronization interval. A manual resynchronization does not affect the periodic
resynchronization schedule. If you manually resynchronize the Enhanced Global Mirror Group when it is
performing an initial synchronization, the manual resynchronization command is rejected.
If you run a manual resynchronization when an Enhanced Global Mirror Group is in the midst of a
periodic synchronization operation, the current process is stopped and the point in time synchronization
points on the primary are discarded. The delta log tracking new host writes and the delta log being used
for the synchronization process are merged. New point in time synchronization points are created and a
new resynchronization is started.
To manually run a resynchronization, run this command:
start enhancedGlobalMirrorGroup synchronize
Changing Enhanced Global Mirroring roles
You can change the mirroring roles of an Enhanced Global Mirror Group, promoting the secondary
storage subsystem to the primary storage subsystem. Each storage subsystem changes roles. First the
original primary becomes the secondary, and then the original secondary becomes the primary. As soon
as the role change completes, all Enhanced Global Mirror Group member logical drives on the
new-primary storage subsystem become fully accessible for host I/O operations. Follow these guidelines
when changing roles:
Chapter 7. About Enhanced Global Mirroring premium feature
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