Red Hat Fence Agents is a collection of scripts to handle remote power management for several devices. They allow failed or unreachable nodes to be forcibly restarted and removed from the cluster.

fence_apc is an I/O Fencing agent which can be used with the APC network power switch. It logs into device via telnet/ssh and reboots a specified outlet. Lengthy telnet/ssh connections should be avoided while a GFS cluster is running because the connection will block any necessary fencing actions.