HP StorageWorks Clustered File System 3.1.1 for Linux Installation Guide (May 2006)

Chapter 4: Install HP Clustered File System 25
When you have completed the fields on the General Settings tab, go to the
Fencing tab.
Fencing
When certain problems occur on a server (for example, hardware
problems or the loss of cluster network communications), and the server
ceases to effectively coordinate and communicate with other servers in
the cluster, Clustered File System must remove the server’s access to
filesystems to preserve data integrity. This step is called fencing.
The Fencing tab allows you to select the method that Clustered File
System should use to remove access to the SAN.