You can use the Resize Volume wizard to modify the size of your flexible volume and dynamically see the results of your changes. The Resize Volume wizard does not support traditional volumes.
Steps
1.
From the Home tab, double-click the appropriate storage system to display a subtree of management features.
2.
Click Storage > Volumes.
3.
Select the volume that you want to resize.
4.
Click Resize to start the Resize Volume wizard.
5.
Type or select information as requested by the wizard.