Exam AWS Certified Solutions Architect - Associate SAA-C03 topic 1 question 47 discussion

Reserved instances are for long term so on-demand will be the right choice - Answer D

***CORRECT*** Option D. Create an On-Demand Capacity Reservation that specifies the Region and three Availability Zones needed. An On-Demand Capacity Reservation is a type of Amazon EC2 reservation that enables you to create and manage reserved capacity on Amazon EC2. With an On-Demand Capacity Reservation, you can specify the Region and Availability Zones where you want to reserve capacity, and the number of EC2 instances you want to reserve. This allows you to guarantee capacity in specific Availability Zones in a specific Region. ***WRONG*** Option A, purchasing Reserved Instances that specify the Region needed, would not guarantee capacity in specific Availability Zones. Option B, creating an On-Demand Capacity Reservation that specifies the Region needed, would not guarantee capacity in specific Availability Zones. Option C, purchasing Reserved Instances that specify the Region and three Availability Zones needed, would not guarantee capacity in specific Availability Zones as Reserved Instances do not provide capacity reservations.

Reserved instances offer either a 1 year or 3 year term commitment. So on demand-instances would satisfy the need above. The answer is D , as the question also requires availability zones.

i always get these wrong

Picked C for this one and failed. Reserved Instances are reserved for 1-3 years so On-Demand Reservation makes more sense.

https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-capacity-reservations.html "On-Demand Capacity Reservations enable you to reserve compute capacity for your Amazon EC2 instances in a specific Availability Zone for any duration"

Guarantee capacity on 3 AZ - on demand reservation, specify region & Availability Zone

***CORRECT*** Option D. Create an On-Demand Capacity Reservation that specifies the Region and three Availability Zones needed. An On-Demand Capacity Reservation is a type of Amazon EC2 reservation that enables you to create and manage reserved capacity on Amazon EC2. With an On-Demand Capacity Reservation, you can specify the Region and Availability Zones where you want to reserve capacity, and the number of EC2 instances you want to reserve. This allows you to guarantee capacity in specific Availability Zones in a specific Region.

Reserved Instances have a commitment over a year so those are out. Option B only allows you to specify the Region and not the AZ. Therefore, D is the only solution.

its B , On-Demand Capacity Reservation allows you to reserve capacity for Amazon EC2 instances in a specific AWS Region, without specifying specific Availability Zones

D is the correct option to guarantee EC2 capacity in specific Availability Zones for a set timeframe. On-Demand Capacity Reservations allow you to reserve EC2 capacity across specific Availability Zones for any duration. This guarantees you will have access to those resources.

Option D is the right answer.

The most appropriate option to guarantee EC2 capacity in three specific Availability Zones in the desired AWS Region for the 1-week event is to create an On-Demand Capacity Reservation that specifies the Region and three Availability Zones (option D). A. Purchasing Reserved Instances that specify the Region needed does not guarantee capacity in specific Availability Zones. B. Creating an On-Demand Capacity Reservation without specifying the Availability Zones would not guarantee capacity in the desired zones. C. Purchasing Reserved Instances that specify the Region and three Availability Zones is not necessary for a short-term event and involves longer-term commitments.

Reserved instances is for long term On-demand Capacity reservation enables you to choose specific AZ for any duration

Just for 1 week so D on demand

I agree that the answer is D because its only needed for a 1 week event. C would be right if it was a re-occurring event for 1 or more years as reserved instances have to be purchased on long term commitments but would satisfy the capacity requirements. https://aws.amazon.com/ec2/pricing/reserved-instances/

D. Reservations are used for long term. A minimum of 1 - 3 years making it cheaper. Whereas, on demand reservation is where you will always get access to CAPACITY it either be 1 week in advance or 1 month in an AZ but you pay On-Demand price meaning there is no discount.