An administrator is configuring vSphere Lifecycle Manager to install patches to a vSphere cluster. The cluster runs workload virtual machines (VMs)…

To minimize downtime during a patching operation where virtual machines (VMs) cannot be migrated, a combination of two features is most effective. First, Quick Boot significantly reduces the ESXi host's reboot time by bypassing the lengthy hardware initialization (POST). This directly shortens the host's maintenance window. Second, since the VMs must be taken offline on the host, setting the VM power state to suspend to memory is the fastest method. This action saves the VM's running state to RAM and allows for a near-instantaneous resumption after the host is back online, minimizing the VM's specific downtime. vSphere Lifecycle Manager allows for configuring both of these settings for remediation tasks.

A. Distributed Power Management (DPM) is for power conservation, not for reducing patching downtime. Suspending to disk is significantly slower than suspending to memory, which increases downtime.
B. While Quick Boot correctly reduces host reboot time, suspending VMs to disk is a slower process than suspending to memory, thus not providing the maximum possible downtime reduction.
C. vSphere High Availability (HA) admission control ensures failover capacity and is unrelated to the speed of a planned patching operation. It does not reduce remediation downtime.

1. VMware vSphere 8.0 Documentation

Managing Host and Cluster Lifecycle

"Remediation Settings for vSphere Lifecycle Manager Baselines"

Section: "VM Power State". This section explicitly states: "You can configure vSphere Lifecycle Manager to change the power state of the virtual machines that run on the hosts that are remediated... Suspend to memory. The virtual machine is suspended and its memory is preserved." This confirms the VM handling part of the answer.

2. VMware vSphere 8.0 Documentation

vSphere Upgrade

"Using vSphere Lifecycle Manager and vSphere Quick Boot". This document states

"When you remediate a cluster

you can use the Quick Boot feature to reduce the time required for the ESXi host remediation. When an ESXi host reboots

it can skip the hardware initialization." This confirms the host handling part of the answer.

3. VMware vSphere 8.0 Documentation

vSphere Virtual Machine Administration

"Suspend and Resume Virtual Machines". This guide explains the suspend operation: "When you suspend a virtual machine

you store its current state... Resuming a suspended virtual machine is faster than powering on a powered off virtual machine." It also differentiates between suspend to memory (standby) and suspend to disk (hibernate)

with the former being faster for resumption on the same host.