DRS

Question 1

The hosts in the cluster must be part of a vSphere vMotion migration network to use vSphere DRS for _______ __________,

Answer 1

load balancing

Question 2

To use shared storage, configure all hosts in the cluster: Datastores must be accessible by _____ and ______ hosts.

Answer 2

source

destination

Question 3

For DRS to work you must place the disks of all virtual machines on ____ ______ that is accessible by source and destination hosts.

Answer 3

shared storage

Question 4

To use vSphere DRS for load balancing, the hosts in your cluster must be part of a vSphere _______ _______.

Answer 4

vMotion network

Question 5

For the initial placement of virtual machines and dynamic balancing while virtual machines are running, you need to configure the _____ ______

Answer 5

automation level

Question 6

What are the three different automation levels?

Answer 6

Manual
Partially automated
Fully Automated

Question 7

Which automation level does the following: When you power on a vm, vSphere DRS displays a list of recommended hosts on which to place the vm. When the cluster becomes imbalanced, vSphere DRS displays recommendations for vm migration.

Answer 7

Manual

Question 8

Which automation level does the following: When you power on a vm, vSphere DRS places it on the best-suited host. When the cluster becomes imbalanced, vSphere DRS displays recommendations for manual vm migration.

Answer 8

Partially automated

Question 9

Which automation level does the following: When you power on a vm, vSphere DRS places it on the best-suited host. When the cluster becomes imbalanced, vSphere DRS migrates virtual machines from overutilized hosts to underutilized hosts to ensure a balanced use of cluster resources.

Answer 9

Fully automated

Question 10

What determines how aggressively vSphere DRS selects to migrate virtual machines?

Answer 10

migration threshold

Question 11

What does the migration threshold do?

Answer 11

• determines how aggressively vSphere DRS selects to migrate vms

Question 12

When Predictive DRS is enabled, The vSphere DRS data collector retrieves statistics from what 2 sources?

Answer 12

• Resource usage statistic from hosts
• Predictive statistic from VMware vRealize® Operations™ server
The predicted usage statistics always take precedence over current usage statistics.

Question 13

By utilizing statistics from vRealize Operations, vSphere DRS can analyze ______ workload on virtual machines in the near future.

Answer 13

expected

Question 14

vSphere DRS can use the _____ _______ values with the current usage values to make placement decisions in advance of the resources being requested.

Answer 14

predicted workload

Question 15

What are affinity rules?

Answer 15

• Use for multi virtual machine systems where virtual
machines communicate heavily with one another.
ex: performance reasons

Question 16

What are anti affinity rules?

Answer 16

• Use for multi virtual machine systems where load balance or high availability is desired.
ex. availability reasons

Question 17

VM or host groups are used in defining _______ _______

Answer 17

affinity rules.

Question 18

You can create one or more vm or host groups in a vSphere DRS cluster, each consisting of one or more vm’s. A vm and host can belong to _____ ______

Answer 18

multiple groups

Question 19

A Virtual Machines to Hosts affinity rule includes the following components: (3)

Answer 19

• A virtual machine DRS group
• A host DRS group
• A designation of whether the rule is a:
-- requirement (must) 
--preference (should) 
--affinity (run on) 
--or anti-affinity (not run on).

Question 20

A _________ rule is softly enforced and can be violated if necessary

Answer 20

preferential

Ex: Separate virtual machines on different blade systems.

Question 21

A _______ rule is strictly enforced and can never be violated.

Answer 21

required

Ex: Enforce host-based ISV licensing.

Question 22

The vSphere DRS tab displays information about the vSphere DRS recommendations made for the cluster, the_____ that occurred in applying such recommendations, and the _____of vSphere DRS
actions.

Answer 22

faults, history

Question 23

Reasons why vSphere HA might not be able to fail over virtual machines:

Answer 23

• vSphere HA admission control is disabled, and resources are insufficient in the remaining hosts to power on all of the failed VMs.
• Required VM-Host affinity rules prevent vSphere HA from failing over.
• Sufficient aggregated resources exist, but they are fragmented across hosts.
In such cases, vSphere HA uses vSphere DRS to try to adjust the cluster by migrating virtual machines to defragment the resources.

Question 24

When a failover occurs, vSphere HA first checks whether resources are available on that host for the failover. If resources are not available, vSphere HA asks vSphere ____ to accommodate for these where possible.

Answer 24

DRS

Question 25

vSphere DRS ______ shares and limits on virtual machines before failover. This process ensures that virtual machines get their entitled resources if they would have been failed over to the correct resource pool.

Answer 25

flattens