The I/O fencing driver uses coordination points to prevent split-brain in a VCS cluster. By default, the fencing driver favors the subcluster with maximum number of nodes during the race for coordination points. With the preferred fencing feature, you can specify how the fencing driver must determine the surviving subcluster.
You can configure the preferred fencing policy using the cluster-level attribute PreferredFencingPolicy as follows:
Enable system-based preferred fencing policy to give preference to high capacity systems.
Enable group-based preferred fencing policy to give preference to service groups for high priority applications.
Disable preferred fencing policy to use the default node count-based race policy.