In VMware vSphere, what happens during a host failure when High Availability (HA) is configured?

When High Availability (HA) is configured in VMware vSphere, the primary function is to ensure that virtual machines (VMs) remain operational in the event of a host failure. In this process, if a host becomes unresponsive or fails, HA automatically detects this situation.

The key action taken is that an alternative host – one that is part of the same cluster and has sufficient resources available – restarts the affected virtual machines that were running on the failed host. This feature eliminates the need for manual intervention, allowing for quicker recovery of VMs and minimal downtime. The process is seamless and designed to maintain business continuity, demonstrating the effectiveness of HA in managing host failures within a virtualized environment.

While the other options mention various actions, they do not accurately represent what happens under HA during a host failure. For instance, powering off VMs on failure is not the intended function of HA, as it aims to keep them running. DRS usually works in conjunction with HA but primarily focuses on resource balancing rather than handling host failures. Lastly, deleting VMs is not an action associated with HA; rather, the goal is to restart and recover them as quickly as possible.