HP StorageWorks Clustered File System 3.2.1 Windows Storage Server Edition Administration Guide (February 2006)

Chapter 8: Configure PSFS Filesystems 76
Extend a Mounted Filesystem
If the Volume allocation display shows that there is space remaining on
the volume, you can use the “Extend Filesystem” option on the Properties
window to increase the size of the PSFS filesystem to the maximum size
of the volume. When you click on the Extend Filesystem button, you will
see a warning such as the following.
When you click Yes, HP Clustered File System will extend the filesystem
to use all of the available space. If the filesystem is on a dynamic volume,
you can use the Extend Volume option to increase the size of both the
dynamic volume and the filesystem.