Final answer:
vSphere HA can protect against host failures, network isolation events, and power failures by restarting virtual machines on other hosts in the cluster, but it does not monitor or protect against specific application failures within virtual machines.
Step-by-step explanation:
vSphere HA (High Availability) is a feature within VMware's vSphere software that provides rapid recovery from outages and improves the availability of virtual machines. The question asks about the types of failures vSphere HA can protect against. Specifically, vSphere HA can protect against the following:
- Host failures: If a server or host fails, vSphere HA can restart the virtual machines that were running on that host on other hosts within the cluster.
- Application failures: While vSphere HA can restart virtual machines if the host fails, it does not directly monitor application failures inside the virtual machine.
- Network failures: vSphere HA can respond to network isolation events, where a host loses network connectivity with the rest of the cluster, by restarting affected virtual machines on other hosts.
- Power failures: In the event of a host power outage, vSphere HA can also restart the affected virtual machines on surviving hosts. However, it does not prevent power failures, and an uninterruptible power supply (UPS) or similar measure would be necessary for power failure mitigation..