Initializing mirror relationships
When you start a mirror relationship, you must initialize that relationship. Initializing a relationship consists of a complete baseline transfer of data from the source volume to the destination. You can use System Manager to initialize a mirror relationship if you have not already initialized the relationship while creating it.
Click Protection > Volume Relationships.
Select the mirror relationship that you want to initialize.
Click Operations > Initialize.
Select the confirmation check box and click Initialize.
Verify the status of the mirror relationship in the Protection window.
A Snapshot copy is created and transferred to the destination. This Snapshot copy is used as a baseline for subsequent incremental Snapshot copies.