Information Technology Reference
In-Depth Information
Solution
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 utiliza-
tion 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.
Ensure vMotion compatibility across processor families.
vMotion requires compatible
CPU families on the source and destination ESXi hosts in order to be successful. To help alle-
viate any potential problems resulting from changes in processor families over time, vSphere
offers Enhanced vMotion Compatibility (EVC), which can mask differences between CPU
families to maintain vMotion compatibility.
Master It
Can you change the EVC level for a cluster while there are VMs running on
hosts in the cluster?
Solution
No, you cannot. Changing the EVC level means that you must calculate and
apply new CPU masks. CPU masks can be applied only when VMs are powered off,
so you can't change the EVC level on a cluster when there are powered-on VMs in that
cluster.
Use Storage vMotion.
Just as vMotion is used to migrate running VMs from one ESXi host
to another, Storage vMotion is used to migrate the virtual disks of a running VM from one
datastore to another. You can also use Storage vMotion to convert between thick and thin
virtual disk types.
Master It
Name two features of Storage vMotion that would help administrators cope
with storage-related changes in their vSphere environment.
Solution
You can use Storage vMotion to facilitate no-downtime storage migrations
from one storage array to a new storage array, greatly simplifying the migration pro-
cess. Storage vMotion can also migrate between different types of storage (FC to NFS,
iSCSI to FC or FCoE), which helps vSphere administrators cope with changes in how the
ESXi hosts access the storage. Finally, Storage vMotion allows administrators to convert
VMDKs between thick and thin, to give them the l exibility to use whichever VMDK for-
mat is most effective for them.
Perform combined vMotion and Storage vMotion.
Using vMotion and Storage at the same
time gives you greater l exibility when migrating VMs between hosts. Utilizing this feature
can also save time when you must evacuate a host for maintenance.
Master It
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 sim-
ply as possible. Which migration option should she choose?
Solution
Storage vMotion, like vMotion, can operate while a VM is running. However,
choosing to perform both migration together will not only allow the VM to stay powered
on, it turns what is regularly a two-step process into a single step.
Coni gure and manage vSphere Distributed Resource Scheduler.
vSphere Distributed
Resource Scheduler enables vCenter Server to automate the process of conducting vMotion
migrations to help balance the load across ESXi hosts within a cluster. You can automate DRS
as you wish, and vCenter Server has l exible controls for affecting the behavior of DRS and
specii c VMs within a DRS-enabled cluster.
Master It
You want to take advantage of vSphere DRS to provide some load balancing
of virtual workloads within your environment. However, because of business constraints,
