Which vSphere feature protects against host hardware failures by restarting virtual machines (VMs) on hosts?

The feature that specifically protects against host hardware failures by automatically restarting virtual machines on other available hosts within a cluster is vSphere High Availability (HA). When a host fails, vSphere HA detects the failure, and then it initiates the process of restarting the VMs that were running on that host on alternative hosts that are still operational in the cluster. This is a crucial aspect of ensuring business continuity, as it minimizes downtime and allows services to be restored quickly without requiring manual intervention.

In contrast, vMotion allows for the live migration of running VMs from one host to another without downtime, but it does not provide failure protection. vSphere Fault Tolerance provides continuous availability for VMs by creating a live shadow instance that can take over instantly, but it does not restart VMs when a host fails. vSphere DRS (Distributed Resource Scheduler) optimizes resource allocation by balancing workloads across hosts, but it also does not offer the capability to restart VMs in the event of a host failure. Thus, vSphere HA is the correct answer as it directly addresses the situation of host hardware failures by ensuring VMs are restarted on healthy hosts.