Chapters 10 - 12 Flashcards Preview

Mastering VMware > Chapters 10 - 12 > Flashcards

Flashcards in Chapters 10 - 12 Deck (23):

Where and when can customization specifications be created in the vSphere Web Client?

You can create customization specifications using the Customization Specification Manager, available from the vSphere Web Client home screen. You can also create customization specifications while cloning VMs or deploying from templates by supplying answers to the
Guest Customization Wizard and saving those answers as a customization specification.


A fellow administrator comes to you and wants you to help streamline the process of deploying Solaris x86 VMs in your VMware vSphere environment. What do you tell him?

You can use cloning inside vCenter Server to help clone VMs that are running Solaris x86, and that will help speed up the process of deploying new VMs. However, the Solaris administrator(s) will be
responsible for customizing the configuration of the cloned VMs because
vCenter Server is unable to customize a Solaris guest OS installation as part of the cloning process.


Of the following tasks, which are appropriate to be performed on a VM running Windows Server 2008 that will eventually be turned into
a template?
a. Align the guest OS’s file system to a 64 KB boundary.
b. Join the VM to Active Directory.
c. Perform some application-specific configurations and tweaks.
d. Install all patches from the operating system vendor.

a. Yes. This is an appropriate task but unnecessary because Windows Server 2008 installs already aligned to a 64 KB boundary. Ensuring alignment ensures that all VMs then cloned from this template will also have their file systems properly aligned.
b. No. This should be done by the vSphere Web Client Guest Customization Wizard or a customization specification.
c. No. Templates shouldn’t have any application-specific files, tweaks, or configurations unless you are planning on creating multiple application-specific templates.
d. Yes. This helps reduce the amount of patching and updating required on any VMs cloned from this template.


Another VMware vSphere administrator in your environment starts the wizard for deploying a new VM from a template. She has a customization specification she’d like to use, but there is one setting in the specification she wants to change. Does she have to create an all-new customization specification?

No. She can select the customization specification she wants to use and then select Use The Customization Wizard To Customize This Specification to supply the alternate values she wants to use for this particular VM deployment. She also has the option of cloning the existing customization specification and then changing the one setting within this new clone. This can be a useful option if these alternate parameters will be used on other clones or templates in the future.


A vendor has given you a zip file that contains a VM they are calling a virtual appliance. Upon looking inside the zip file, you see several VMDK files and a VMX file. Will you be able to use vCenter Server’s Deploy OVF Template functionality to import this VM? If not, how can you get this VM into your infrastructure?

You will not be able to use vCenter Server’s Deploy OVF Template feature; this requires that the virtual appliance be provided with
an OVF file that supplies the information that vCenter Server is expecting to find. However, you can use vCenter Converter to perform a V2V
conversion to bring this VM into the VMware vSphere environment, assuming it is coming from a compatible source environment.


You are preparing to export a VM to an OVF template. You want to ensure that the OVF template is easy to transport via a USB key or
portable hard drive. Which format is most appropriate, OVF or OVA? Why?

The OVA format is probably a better option here. OVA
distributes the entire OVF template as a single file, making it easy to copy
to a USB key or portable hard drive for transport. Using OVF would mean
keeping several files together instead of working with only a single file.


List the file types that cannot be added to Content Libraries for synchronization.

Any file type can be uploaded to a Content Library. All files will be synchronized as configured without changes. VM templates not in OVF format will be converted to OVF format as they are being uploaded, however.


Name two ways to add VMs to a vApp

There are four ways to add VMs to a vApp: create a new VM in the vApp, clone an existing VM into a new VM in the vApp, deploy a VM
into the vApp from a template, and drag and drop an existing VM into the


To guarantee certain levels of performance, your IT director believes that all VMs must be configured with at least 8 GB of RAM.
However, you know that many of your applications rarely use this much
memory. What might be an acceptable compromise to help ensure performance?

One way would be to configure the VMs with 8 GB of RAM and specify a reservation of only 2 GB. VMware ESXi will guarantee that every VM will get 2 GB of RAM, including preventing additional VMs from being
powered on if there isn’t enough RAM to guarantee 2 GB of RAM to that new VM. However, the RAM greater than 2 GB is not guaranteed and, if it is not being used, will be reclaimed by the host for use elsewhere. If plenty
of memory is available to the host, the ESXi host will grant what is requested; otherwise, it will arbitrate the allocation of that memory
according to the share values of the VMs.


You are configuring a brand-new large-scale VDI environment but you’re worried that the cluster hosts won’t have enough RAM to
handle the expected load. Which advanced memory-management technique will ensure that your virtual desktops have enough RAM
without having to use the swap file?

Transparent page sharing (TPS) ensures that if you have multiple VMs with the same blocks of memory, you allocate it only once.
This can almost be thought of as “de-duplication for RAM.” Within virtual desktop environments, many VMs are run as “clones” with their operating system and applications all identical—a perfect case for TPS to take
advantage of.


A fellow VMware administrator is a bit concerned about the use
of CPU reservations. She is worried that using CPU reservations will “strand” CPU resources, preventing those reserved but unused resources from being used by other VMs. Are this administrator’s concerns well

For CPU reservations, no. Although it is true that VMware must have enough unreserved CPU capacity to satisfy a CPU reservation when a VM is powered on, reserved CPU capacity is not “locked” to a VM. If a VM
has reserved but unused capacity, that capacity can and will be used by other VMs on the same host. The other administrator’s concerns could be valid, however, for memory reservations.


Your company runs both test/development workloads and production workloads on the same hardware. How can you help ensure that test/development workloads do not consume too many resources and impact the performance of production workloads?

Create a resource pool and place all the test/development VMs
in that resource pool. Configure the resource pool to have a CPU limit and
a lower CPU shares value. This ensures that the test/development VMs
will never consume more CPU time than specified in the limit and that, in times of CPU contention, the test/development environment will have a
lower priority on the CPU than production workloads.


Name two limitations of Network I/O Control.

Network I/O Control works only with vSphere Distributed Switches and it requires vCenter Server in order to operate. Another limitation is that system network resource pools cannot be assigned to
user-created port groups.


What are the requirements for using Storage I/O Control?

All datastores and ESXi hosts that will participate in Storage I/O Control must be managed by the same vCenter Server instance. In
addition, raw device mappings (RDMs) are not supported. Datastores must
have only a single extent; datastores with multiple extents are not supported.


You have a VM that has a large I/O requirement. Which flash feature should you configure and why?

vFRC should be used. This feature acts like a buffer to help accelerate I/O for configured disks within individual VMs. The other
feature, Swap to Host Cache, is for environments that are memory overcommitted.


A certain vendor has just released a series of patches for some of the guest OSs in your virtualized infrastructure. You request an outage window from your supervisor, but your supervisor says to just use vMotion to prevent downtime. Is your supervisor correct? Why or why not?

Your supervisor is incorrect. vMotion can be used to move running VMs from one physical host to another, but it does not address outages within a guest OS because of reboots or other malfunctions. If you had been requesting an outage window to apply updates to the host, the supervisor would have been correct—you could use vMotion to move all the VMs to other hosts within the environment and then patch the first
host. There would be no end-user downtime in that situation.


Is vMotion a solution to prevent unplanned downtime?

No. vMotion is a solution to address planned downtime of the ESXi hosts on which VMs are running, as well as to manually load-balance
CPU and memory utilization across multiple ESXi hosts. Both the source and destination ESXi hosts must be up and running and accessible across the network in order for vMotion to succeed.


Can you change the EVC level for a cluster while there are VMs running on hosts in the cluster?

No, you cannot. Changing the EVC level means that you must calculate and apply new CPU masks. CPU masks can be applied only whenVMs are powered off, so you can’t change the EVC level on a cluster when there are powered-on VMs in that cluster.


Name two features of Storage vMotion that would help you cope with storage-related changes in your vSphere environment.

You can use Storage vMotion to facilitate no-downtime storage migrations from one storage array to a new storage array, greatly simplifying the migration process. Storage vMotion can also migrate
between different types of storage (FC to NFS, iSCSI to FC or FCoE), which helps you cope with changes in how the ESXi hosts access the storage. Finally, Storage vMotion allows you to convert VMDKs between thick and thin, to give you the flexibility to use whichever VMDK format is most effective for you.


A fellow administrator is trying to migrate a VM to a different datastore and a different host while it is running and wishes to complete the task as quickly and as simply as possible. Which migration option
should she choose?

Storage vMotion, like vMotion, can operate while a VM is running. However, choosing to perform both migrations together will not
only allow the VM to stay powered on, it also turns what is regularly a two step process into a single step.


You want to take advantage of vSphere DRS to provide some load balancing of virtual workloads within your environment. However,
because of business constraints, you have a few workloads that should not
be automatically moved to other hosts using vMotion. Can you use DRS? If so, how can you prevent these specific workloads from being affected by DRS?

Yes, you can use DRS. Enable DRS on the cluster, and set the DRS automation level appropriately. For those VMs that should not be automatically migrated by DRS, configure a VM Override set to Manual. This will allow DRS to make recommendations on migrations for these workloads but it will not actually perform the migrations.


Name the two ways in which an administrator is notified that a Storage DRS recommendation has been generated.

On the Storage DRS tab of a datastore cluster, the
recommendation(s) will be listed with an option to apply the recommendations. In addition, on the Alarms tab of the datastore cluster, an alarm will be triggered to indicate that a Storage DRS recommendation exists.


What is a potential disadvantage of using drag-and-drop to add a datastore to a datastore cluster?

When you use drag-and-drop to add a datastore to a datastore cluster, the user is not notified if the datastore isn’t accessible to all the
hosts that are currently connected to the datastore cluster. This introduces
the possibility that one or more ESXi hosts could be “stranded” from a VM’s virtual disks if Storage DRS migrates them onto a datastore that is not accessible from that host.