You can migrate between fencing configurations without incurring application downtime in the VCS clusters.
You can migrate from disk-based fencing to server-based fencing in the following cases:
You want to leverage the benefits of server-based fencing.
You want to replace faulty coordinator disks with coordination point servers (CP servers).
Similarly, you can migrate from server-based fencing to disk-based fencing when you want to perform maintenance tasks on the CP server systems.