You can manually enable protection domain monitoring using the NetApp Element Configuration extension point. You can select a protection domain threshold based on node or chassis domains.
A chassis domain emphasizes the resiliency of the cluster to withstand a chassis-level failure. A node domain emphasizes a select group of nodes, potentially across chassis. A chassis domain requires more potential capacity resources than a node domain to be resilient to failure. When a protection domain threshold is exceeded, a cluster no longer has sufficient capacity to heal from failure while also maintaining undisrupted data availability.