A vROps cluster in a Continuous Availability configuration consists of two fault domains, which are separate physical locations that can tolerate failures of an entire rack or site. The fault domains contain the primary node, the primary replica node, and the data nodes that store and replicate the data and configuration of the cluster. The witness node is deployed in a third location to monitor the network connectivity between the two fault domains and prevent split-brain scenarios, which occur when both fault domains assume the role of the master node due to network isolation1.
When a network outage occurs between the two fault domains, the witness node detects the situation and makes one of the fault domains offline to avoid data inconsistency. The fault domain that can still contact the witness node remains online and continues to function as the master node. The fault domain that cannot contact the witness node goes offline and stops serving requests. The VMs on the offline fault domain are restarted on the online fault domain by the vSphere HA feature1.
When the network outage is resolved and the connectivity between the two fault domains is restored, the vROps cluster will bring the offline fault domain back automatically. The offline fault domain will resync the data and configuration from the online fault domain and resume its normal operations. The administrator does not need to bring the offline fault domain online manually or restart and resync the vROps cluster1.
Therefore, the two events that will occur as a result of the outage are A.
The vROps cluster will bring the fault domain back automatically once the network has been restored and D.
One fault domain will go offline.
References: 1: About vRealize Operations Continuous Availability