When creating a SAN/storage fence device (that is, one that uses a non-power based fencing agent), you must set the meta option
provides=unfencing when creating the
stonith device. This ensures that a fenced node is unfenced before the node is rebooted and the cluster services are started on the node.
provides=unfencing meta option is not necessary when configuring a power-based fence device, since the device itself is providing power to the node in order for it to boot (and attempt to rejoin the cluster). The act of booting in this case implies that unfencing occurred.
The following command configures a stonith device named
my-scsi-shooter that uses the
fence_scsi fence agent, enabling unfencing for the device.
pcs stonith create my-scsi-shooter fence_scsi devices=/dev/sda meta provides=unfencing