Having workloads and vCenter Servers always available to avoid service disruption is the main responsibility of every vSphere Administrator. This chapter will explain the vSphere Availability feature (formerly known as vSphere HA) and the configuration settings used in a cluster to ensure virtual machine availability in the case of an expected host failure event.

The vCenter Server is the core component of the infrastructure because it provides all the main services and features that are available in vSphere, such as vSphere Availability, DRS, vDS, and so on, and its availability must be ensured to keep the infrastructure healthy. This chapter will also cover the configuration of vCenter Server Appliance (vCSA) HA, a new feature that became available in vSphere 6.5 (vCSA only) to ensure vCenter Server HA.