VCP-DCV vSphere Performance and Scaling Practice Test 7 — 15 Questions

Question 1

Arrange the steps to add an existing virtual machine to a vCenter Server inventory.

Accepted Answer

Right-click a datacenter or folder, click 'Add Existing Virtual Machine', browse to and select the VM's .vmx file, then click Finish.. The correct sequence to add an existing VM to vCenter inventory is: right-click a datacenter or folder, select 'Add Existing Virtual Machine', browse to the VM's .vmx file, and click Finish. This order ensures the wizard is properly initiated and the VM is registered in the desired inventory location.

Answer

Browse to and select the VM's .vmx file, right-click a datacenter or folder, click 'Add Existing Virtual Machine', then click Finish.

Answer

Click 'Add Existing Virtual Machine', right-click a datacenter or folder, browse to the VM's .vmx file, then click Finish.

Answer

Right-click a datacenter or folder, click Finish, browse to and select the VM's .vmx file, then click 'Add Existing Virtual Machine'.

Question 2

A company has a cluster of 4 ESXi hosts. They want to ensure that virtual machines are automatically distributed evenly across hosts based on CPU and memory load. Which feature should be enabled on the cluster?

Accepted Answer

vSphere DRS. DRS (Distributed Resource Scheduler) automatically balances VM loads based on resource usage. HA provides high availability, FT provides fault tolerance, and DPM manages host power.

Answer

vSphere HA

Answer

Fault Tolerance

Answer

Distributed Power Management

Question 3

An administrator has a vSphere 7 cluster with vMotion enabled. They need to perform a vMotion of a VM from host1 to host2 while preserving the VM's memory state. The VM has a PCIe passthrough device assigned (NVMe controller). What should the administrator do before initiating the vMotion?

Accepted Answer

Remove the PCIe passthrough device from the VM. vMotion does not support VMs with PCIe passthrough devices because the device is tied to the physical host. The device must be removed or the VM must be powered off.

Answer

Use shared storage for the VM

Answer

Enable Enhanced vMotion Compatibility (EVC) on the cluster

Answer

Upgrade to vSphere 8

Question 4

A vSphere environment experiences periodic performance degradation during peak business hours. Analysis shows that one ESXi host's CPU ready time for a specific mission-critical VM is consistently above 20%. Which corrective action should be taken first?

Accepted Answer

Migrate the VM to a different host with lower CPU utilization. CPU ready time above 20% indicates the VM is waiting for physical CPU resources because the host is overcommitted or contended. The first corrective action should be to migrate the VM to a less-utilized host (vMotion), which immediately relieves contention without changing the VM's configuration. This addresses the root cause — host-level CPU contention — rather than masking it.

Answer

Increase the VM's memory reservation

Answer

Set a higher CPU limit on the VM

Answer

Add more vCPUs to the VM

Question 5

Which tool provides real-time performance monitoring at the ESXi host level, including CPU, memory, network, and storage metrics?

Accepted Answer

esxtop. esxtop is a command-line tool that provides real-time host performance data. vCenter performance charts are historical. resxtop is for remote usage, and dcli is a different tool.

Answer

dcli

Answer

resxtop

Answer

vCenter performance charts

Question 6

A VM configured with 4 vCPUs shows high co-stop time in performance metrics. What does co-stop time indicate and which action should be taken to improve performance?

Accepted Answer

Reduce the number of vCPUs to match workload requirements. Co-stop time is time when the VM is ready to run but waiting for all vCPUs to be scheduled simultaneously. Reducing the number of vCPUs can alleviate this.

Answer

Add more vCPUs to the VM

Answer

Enable hyperthreading on the host

Answer

Increase the VM's memory reservation

Question 7

Which THREE vSphere features directly contribute to performance and scaling of virtualized workloads? (Select THREE.)

Accepted Answer

vSphere vMotion. vSphere vMotion (A) is correct because it enables live migration of running VMs between hosts with no downtime, which supports performance and scaling by allowing workload redistribution and maintenance without service interruption. Storage I/O Control (B) is correct because it enforces per-VM or per-datastore I/O shares and limits during congestion, directly managing storage performance and preventing noisy-neighbor effects in scaled environments. vSphere DRS (C) is correct because it continuously balances CPU and memory load across hosts in a cluster using vMotion, directly improving performance and enabling horizontal scaling. Fault Tolerance (D) and vSphere HA (E) are not correct here because they primarily provide availability and rapid recovery from host failures, not direct performance or scaling optimization of virtualized workloads.

Answer

vSphere Fault Tolerance

Answer

vSphere HA

Question 8

Refer to the exhibit. The vSphere administrator observes that vm1 has a %RDY value of 20.5. What is the most likely cause of this high ready time?

Accepted Answer

The host's physical CPUs are overcommitted. %RDY (ready time) measures the percentage of time a VM's virtual CPUs are ready to run but cannot be scheduled onto a physical CPU because the host's pCPUs are busy. A sustained value of 20.5% indicates significant CPU contention, meaning the host's physical cores are overcommitted relative to the total vCPU demand of all powered-on VMs. This is a classic symptom of CPU over-subscription on the ESXi host.

Answer

The VM is experiencing network packet loss

Answer

The VM's virtual disk is causing I/O latency

Answer

Insufficient memory is allocated to vm1

Question 9

An administrator wants to limit the amount of CPU resources a single VM can consume in a vSphere cluster. Which feature should be used?

Accepted Answer

CPU limit. A CPU limit sets an upper bound on the amount of physical CPU resources a VM can consume, expressed in MHz. When the VM reaches the limit, it is throttled even if the host has idle capacity. This directly addresses the requirement to cap a single VM's CPU consumption.

Answer

CPU affinity

Answer

CPU reservation

Answer

Resource pools

Question 10

A VM with a large memory footprint is experiencing high swap rates. The host has free memory but the swap rate is still high. What is the most likely cause?

Accepted Answer

The VM's memory limit is set too low.. A VM memory limit in vSphere caps the amount of host physical memory the VM can consume. When the limit is lower than the guest's working set, the VM balloons and then swaps to its .vswp file even though the host has free memory, because the limit — not host pressure — is driving reclamation. Raising or removing the limit resolves the swap.

Answer

The VM's virtual machine swap file is on a slow datastore.

Answer

The host is using software iSCSI causing high latency.

Answer

The VM's memory reservation is set too high.

Question 11

A vSphere cluster with DRS enabled is experiencing an imbalance in resource utilization across hosts. DRS is set to 'Manual' mode. What action should the administrator take to resolve the imbalance?

Accepted Answer

Manually migrate VMs using vMotion.. In DRS Manual mode, vSphere generates migration recommendations but does not execute them automatically. The administrator must manually apply the recommended vMotion migrations to rebalance the cluster. Changing to Fully Automated would automate future balancing but does not immediately resolve the current imbalance without manual intervention.

Answer

Change DRS to 'Fully Automated' mode.

Answer

Enable HA admission control.

Answer

Increase the DRS migration threshold.

Question 12

Which THREE techniques are recommended to improve virtual machine network performance in a vSphere environment? (Select three.)

Accepted Answer

Enable Jumbo Frames on the virtual switch.. Option A is correct because enabling Jumbo Frames (MTU 9000) on the virtual switch, physical uplinks, and guest OS reduces per-packet overhead and CPU utilization, improving throughput for large data transfers. Option B is correct because the VMXNET3 adapter is a paravirtualized NIC designed for vSphere that delivers higher throughput and lower CPU utilization than emulated adapters like e1000e. Option E is correct because SR-IOV on supported NICs allows a virtual function to be passed directly to the VM, bypassing the hypervisor's virtual switch datapath for near-native network performance and reduced latency. Option C is not recommended because dedicating a separate virtual switch per VM adds management overhead and does not inherently improve performance; standard vSwitch design uses shared switches with proper uplink and teaming configuration. Option D is incorrect because e1000e is an emulated Intel adapter that offers lower performance and higher CPU overhead than VMXNET3.

Answer

Use a dedicated virtual switch for each VM.

Answer

Use the e1000e network adapter type.

Question 13

Which TWO are correct statements about vSphere resource pools? (Select two.)

Accepted Answer

Resource pools can be nested.. Correct: A (resource pools can be nested) and E (resource pools can have shares, limits, and reservations). Option B is false because resource pools aggregate resources for multiple VMs, not isolate individual VMs. Option C is false because child resource pools do not inherit settings from their parent by default; they have their own allocations unless explicitly configured. Option D is false because resource pools are available on standalone hosts as well as clusters.

Answer

Resource pools can be used to isolate performance for individual VMs.

Answer

Resource pools inherit settings from parent pools by default.

Answer

Resource pools are only available in clusters.

Question 14

A vSphere administrator notices that one ESXi host in a DRS-enabled cluster is consistently running at 95% CPU utilization while other hosts average 40%. Which action should the administrator take to determine the cause?

Accepted Answer

Review the host's performance charts in vCenter for CPU contention metrics.. The correct first step in diagnosing a performance imbalance is to gather data before changing configuration. Reviewing the host's performance charts in vCenter provides CPU contention metrics such as CPU usage, ready time, and co-stop, which reveal whether the host is genuinely overloaded or if VMs are contending for resources. This evidence-based approach identifies the root cause before any DRS tuning is attempted.

Answer

Increase the DRS migration threshold from 3 to 5.

Answer

Place the host into maintenance mode to isolate the problem.

Answer

Set the DRS automation level to Fully Automated.

Question 15

An ESXi host experiences high memory ballooning in virtual machines. The administrator checks the host's memory metrics and sees a high swap rate. The host has 512 GB of memory, and the VMs are configured with memory reservations. Which configuration is most likely contributing to the excessive swapping?

Accepted Answer

Memory overcommitment is high, and some VMs have large memory reservations.. High memory overcommitment combined with large VM memory reservations forces ESXi to reclaim memory from unreserved VMs via ballooning and, when that is insufficient, host-level swapping. Reservations lock physical memory for some VMs, leaving less for others, which amplifies ballooning and swap activity on the overcommitted host. The correct fix is to reduce overcommitment or right-size reservations.

Answer

Memory shares are set too low for the VMs experiencing ballooning.

Answer

The host is configured for NUMA interleaving, causing memory access delays.

Answer

Transparent Page Sharing (TPS) is enabled and is aggressively sharing memory pages.