Which of the following are characteristics of a reserved instance?

Which of the following are characteristics of a reserved instance? Choose 3 answers

Which of the following are characteristics of a reserved instance? Choose 3 answers

A.
It can be migrated across Availability Zones

B.
It is specific to an Amazon Machine Image (AMI)

C.
It can be applied to instances launched by Auto Scaling

D.
It is specific to an instance Type

E.
It can be used to lower Total Cost of Ownership (TCO) of a system



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T

T

Nonuser, I think C is wrong, http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/concepts-on-demand-reserved-instances.html. But I am not 100% sure about it

niraj

niraj

What makes you think that it cannot be applied to AutoScaling.

Reserved instance is a way to purchase a dedicated pricing for a type/class and region/az . You can use it anyway you want. Whether by spinning up new instances via the classic way or use autoscaling. Keeping in mind that if you have 5 reserved instances and your autoscaling scales beyond that then you will be charged for it.

T

T

My last comment is wrong.
Nonuser is right:
A,C,E – is the right answer

Sam

Sam

Why D is not correct? – Even though you have to choose which instance type you want your reserved instance to be you have an option to modify it. So C is more appropriate

taka

taka

C is wrong.

http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/concepts-on-demand-reserved-instances.html
You can use Auto Scaling or other AWS services to launch the On-Demand instances that use your Reserved Instance benefits.

Not Reserved Instance but On-Demand instances can be applied to instances launched by Auto Scaling.

Pooj

Pooj

When you purchase a Reserved Instance, the reservation is automatically applied to running instances that match your specified parameters. Alternatively, you can launch an On-Demand EC2 instance with the same configuration as the reservation, and the billing benefit is applied automatically.

So, if you purchased two c4.xlarge, default tenancy, Linux Reserved Instances for the US East (N. Virginia) region, up to two c4.xlarge, default tenancy, Linux instances running in the US East (N. Virginia) region can benefit from the Reserved Instance discount

Correct Ans: A, C, E.

EuroAnchor

EuroAnchor

Its a trick question, they don’t ask what are “characteristics of a reserved instance that do not apply to on demand” , its just what are characteristics of a reserved instance

justmy2centx

justmy2centx

A.It can be migrated across Availability Zones
D.It is specific to an instance Type
E.It can be used to lower Total Cost of Ownership (TCO) of a system

————
B.
It is specific to an Amazon Machine Image (AMI) — Not True

C.
It can be applied to instances launched by Auto Scaling — http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/concepts-on-demand-reserved-instances.html
You can use Auto Scaling or other AWS services to launch the On-Demand instances that use your Reserved Instance benefits.

Not Reserved Instance but On-Demand instances can be applied to instances launched by Auto Scaling.

KwagongMakisig

KwagongMakisig

it looks like ACD and E are all correct!
Which leaves a wrong question

Kelvin Wong

Kelvin Wong

ACD

B – incorrect, any EC2 launched from any AMI can be reserved
D – incorrect, you can purchase reserved instance for any type

C –> “You can use Auto Scaling or other AWS services to launch the On-Demand instances that use your Reserved Instance benefits.”

The confusion by most folks is C and how reserved instance work. You purchase reserved instance capacity based on AZ, instance type, platform and tenancy. Say you buy 4 reserved t1.micro instance, you then launch 5 on-demand t1.micro instance in that AZ. You cost will be 4 x reserved instance and 1 x on-demand instance. If you purchase for say 1 year and stop and you kept all 5 instance running, then you will be charge 5 x on-demand instance price.

So if you have auto-scaling and you bought 10 reserved instance, when you fire up to 10 on-demand instances in the auto-scaling group, they will be charge at reserved instance pricing

manishkhairnar

manishkhairnar

The answer should be B D E

Refer to the link below.
https://aws.amazon.com/ec2/faqs/#reserved-instances.html

And read question,
Q: How do I reserve capacity for an existing, running instance?
A: The reservation must match the following attributes of the running instance you want to cover:

Availability Zone (e.g., us-east-1a) — hence A is wrong
Instance type (e.g., m3.large) — hence D is correct
Platform (e.g., Linux/UNIX (Amazon VPC)) — hence B is correct
Tenancy (e.g., default)

seenagape

seenagape

I choose ADE

Sachin

Sachin

Has anyone taken this exam to confirm if these questions are on there?

Senator

Senator

ADE seems the most appropriate answers

Senator

Senator

ADE are correct.

B&C are wrong, reason is

B >> It is not peculiar to an AMI, it is a contract you go into to have a machine for 1 or 3 yrs with the aim of getting huge discounts

C >>> This is also wrong, you do not put reserved instances on auto grouping as it does not make any economic sense since you are already paying for the reserved machine, so even if it is not in use, you are still charged for it as it is a contract.

kamleshj

kamleshj

ADE

A: Switch Availability Zones within the same region
D:Change the instance size within the same instance type
E:Amazon Elastic Compute Cloud (Amazon EC2) and Amazon Relational Database Service (Amazon RDS) provide different
ways to purchase an instance (virtual server) in the cloud. The On-Demand Instance pricing option lets you purchase an
instance by the hour with no long-term commitments—you turn capacity on and off instantly. The Reserved Instance
(RI) pricing option lets you make a low, one-time payment for each instance you want to reserve, and in turn, you
receive a significant discount on the hourly usage charge for that instance, and are guaranteed capacity. The Spot
Instance pricing option (available only for Amazon EC2) allows you to bid for unused compute capacity. Instances are
charged at the Spot Price, which fluctuates periodically depending on the supply and demand for Spot Instance capacity.
Functionally, Reserved Instances, On-Demand Instances, and Spot Instances are the same.
When you are comparing TCO, we highly recommend that you use the Reserved Instance (RI) pricing option in your
calculations.
They will provide the best apples-to-apples TCO comparison between on-premises and cloud infrastructure.
Reserved Instances are similar to on-premises servers because in both cases, there is a one-time upfront cost. However,
unlike on-premises servers, Reserved Instances can be “purchased” and provisioned within minutes—and you have the
flexibility to turn them off when you don’t need them and stop paying the hourly rate.

CM

CM

question is about characteristics of a reserved instance? Choose 3 answers

A.
It can be migrated across Availability Zones

B.
It is specific to an Amazon Machine Image (AMI)

C.
It can be applied to instances launched by Auto Scaling

D.
It is specific to an instance Type

E.
It can be used to lower Total Cost of Ownership (TCO) of a system

Just looking at the instance you can say
What is the AMI
What is the instance type
Since it is reserved, it cost less.
All these are characteristic of a resvered instance
So Answer is BDE

Mayur

Mayur

ACDE are correct. Instead of 3 correct answer there are 4 correct options

vladam

vladam

The confusion about option D regarding ability to change the instance type is because there are different reserved instance types as described here:
https://aws.amazon.com/ec2/faqs/#reserved-instances.html

Q: Can I reassign my Standard Reserved Instance from one instance type (e.g., c1.xlarge) to another (e.g., m1.large)?

No. A Standard Reserved Instance is associated with a specific instance type for the duration of its term; however, you can change from one instance size (e.g., c3.large) to another (e.g., c3.xlarge) in the same type, if it is a Linux/UNIX Reserved Instance. If you’d like to have flexibility among instance types, we recommend purchasing a Convertible Reserved Instance. Please refer to the Convertible Reserved Instances section of the FAQ for additional information.

Since you can not change instance type for all reserved instances but only for Convertible ones option D is not correct.

Right answer is A, C, E.

nebz

nebz

@Vladam : you can modify the instance type with api ModifyReservedInstances for standard reserved instance

nebz

nebz

you have right it’s just size not type 🙂 sorry

ninh nguyen

ninh nguyen

i choose CDE because:
– Reserved Instances provide you with a significant discount compared to On-Demand instance pricing.>>> E is correct
-when Reserved Instances are assigned to a specific Availability Zone, they provide a capacity reservation. >>> A is not correct
-You can use Auto Scaling or other AWS services to launch the On-Demand instances that use your Reserved Instance benefits. >>> D is correct
-A Standard Reserved Instance is associated with a specific instance type for the duration of its term >>> C is correct
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/concepts-on-demand-reserved-instances.html

HotTea

HotTea

A is correct, listen to this @1:55 into the video
ADE, deaclaring Ami type is not reqd. for RIs

ranbira

ranbira

A is wrong, I know what you are thinking but listen me out for once.

A reserved instance’s reservation can be APPLIED ACROSS Availability zones within a region. It cannot be MIGRATED. You cannot take 3 RIs from AZ-A and put them in AZ B. if you launch 3 in AZ A and 3 in AZ B, the reservation will be applied in a manner such that cost is minimised.

On top of that no matter how much you argue, you cannot “migrate” an RI from AZ A of Region 1 to AZ X of Region 3. Hence option A is invalidated.

mfaz

mfaz

A,D,E –

A reserved instance is not an instance per se, but a reserved set of resources pre-purchased that is applied to instance deployments. In other words, capacity reservation in the form of an instance type.

So A works because all EC2 instances can traverse AZs via migration.
B doesnt work because you can deploy any AMI to an instance that you could with any other instance type.
C doesn’t work. You CAN auto scale from a reserved instance, BUT the instances scaled to are On-Demand not more reserved instances. See the link –
http://stackoverflow.com/questions/30873849/use-reserved-instance-and-autoscaling-group
D works because you are reserving the instance type specifically
E works because you can pay for all or part of an entire year or 3 years usage up front

shaam

shaam

C, D & E –

D is correct – “if you purchased two c4.xlarge, default tenancy, Linux Reserved Instances for the US East (N. Virginia) region, up to two c4.xlarge, default tenancy, Linux instances running in the US East (N. Virginia) region can benefit from the Reserved Instance discount.” – so Reserved Instances are specific to an instance type.

C is also correct since they can be launched by Auto Scaling

E is correct since they lower the Total Cost of ownership – which everyone agrees

Humberto

Humberto

ACE

Sorry Lads, D is wrong:

http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/reserved-instances-types.html

There are two types of Reserved Instances:
– Standard Reserved Instances
– Convertible Reserved Instances (That’s the point)

Convertible Reserved Instances can be purchased for a three-year term and exchanged for Convertible Reserved Instances with different instance families, platform, tenancy, or scope during the term.

Nowhere is it specified that it should be a Standard Reserved Instance

Even in the UJ’s video “https://aws.amazon.com/es/ec2/pricing/reserved-instances/#5”, they say (2 min 05 sec) “For a linux reserved instances, you can modify your instance type to another size in the same family at no extra cost”

Amit

Amit

Regarding option C – read the sentence “It can be applied to instances launched by Auto Scaling”.. it says “it can be applied to auto scaling instances”, you cannot specifically apply to auto scaling instances which are automatically launched.

Option D is accurate as it says “it is specific to Instance Type” , it is true regardless of whether you can change the instance type or not.

so i will go with A D E as Answers

Charles

Charles

CDE maybe right, before 2years. BUT now, ACDE are all correct.

Nagaraj

Nagaraj

A D E is more appropriate…

CW

CW

A is correct based on this:

Change Availability Zone,
instance size (for Linux OS),
networking type

Yes (Using ModifyReservedInstances API and console) Yes (Using ExchangeReservedInstances API and console)

https://amazonaws-china.com/ec2/pricing/reserved-instances/

how ever, D is also right.. since one time , only one instance type associated to RI

Midhun

Midhun

A,D,E are right answers as the question asks for the “”characteristics”” of reserved instances.
This makes C a wrong answer. C applies when the question asks what are the correct statements for the reserved instances?
Explanation:
Although reserved instances can be used for Auto-scaling but is not recommended as the basic property of auto scaling is “to save money by launching instances when they are actually needed and terminating them when they aren’t needed”
http://docs.aws.amazon.com/autoscaling/latest/userguide/auto-scaling-benefits.html

some.guy

some.guy

The semantics are important.

Instance Type != Instance Family

Instance Type == (Instance Family) + (Instance Size)

Standard RIs offer a significant discount on EC2 instance usage when you commit to a particular Instance Family.

Option D is wrong.

Panth Shah

Panth Shah

Answer – Option A, C and E.

Option A is correct, because you can migrate instances between AZ’s. Please refer to the link for the confirmation on this case –

http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ri-modifying.html

Option D is incorrect because it is specific to instance family however instance type can be changed.

Also when you create a reserved instance, you can see the Instance Type as an option.

Option E is correct, because reserved instances can be used to lower costs. Reserved Instances provide you with a discount on usage of EC2 instances, and a capacity reservation when they are applied to a specific Availability Zone, giving you additional confidence that you will be able to launch the instances you have reserved when you need them.

For more information on reserved instances, please visit the link –

https://aws.amazon.com/ec2/pricing/reserved-instances/

The correct answers are: It can be migrated across Availability Zones, It can be applied to instances launched by Auto Scaling, It can be used to lower Total Cost of Ownership (TCO) of a system