NetApp
SnapMirror : Managing protection : Updating a SnapMirror relationship

Updating a SnapMirror relationship
You can use the Protection window to initiate an unscheduled SnapMirror update of the destination. You may have to perform a manual update to prevent data loss due to an upcoming power outage, scheduled maintenance, or data migration.
Steps 
1.
From the Home tab, double-click the appropriate storage system.
2.
In the navigation pane, click SnapMirror.
3.
Select the SnapMirror relationship that you want to update.
4.
Click Operations > Update.
5.
Click Update.