Exam AWS Certified Cloud Practitioner topic 1 question 291 discussion

Please note - Auto scaling does not scale up or down (vertical scaling). it is used to increase/ decrease the number of EC2 instances i.e. scaling out or in ~ Horizontal Scaling.

Capacity wise, would be up / down scaling as I see it...

The thing is that the question asks for scaling "capacity". So the "C" option suits better than "A".

Amazon EC2 Auto Scaling groups are used to automatically adjust the number of EC2 instances in your fleet based on demand or predefined conditions. Scaling in and out refers to increasing or decreasing the number of instances in response to changes in the demand for your application. EC2 Auto Scaling helps you maintain the desired number of instances to handle the load efficiently and cost-effectively.

scale the number, scale out as needed. https://docs.aws.amazon.com/autoscaling/ec2/userguide/what-is-amazon-ec2-auto-scaling.html

A. Scale the number of EC2 instances in or out automatically, based on demand.

It's C folks, the question mentions the "capacity", so scale the size up or down

Certainly A

A is the answer.

A. Scale the number of EC2 instances in or out automatically, based on demand. Amazon EC2 Auto Scaling groups allows you to automatically scale the number of Amazon Elastic Compute Cloud (EC2) instances in your application in or out, in response to changes in demand for your application. This helps ensure that you have the correct number of instances running to handle the traffic to your application. Auto Scaling can be configured to use CloudWatch alarms to determine when to scale the number of instances, and it can also be configured to scale based on a schedule. This can be done by creating policies that increase or decrease the number of instances, based on CloudWatch metrics, schedule or even by using a custom metric. It is important to mention that Auto Scaling groups can also scale the size of EC2 instances up or down, but this is not the only way to use it.

Its in and out

Other sites refer to EC2 Autoscale as In/Out ex: https://spot.io/resources/aws-autoscaling/ec2-autoscaling-the-basics-and-4-best-practices/#a6

A. scale in/out

All your explanation point to A as the answer. We increase the NUMBER of EC2 instances thus increasing the SIZE of the group

From the reference: You can use Amazon EC2 Auto Scaling to automatically increase the number of Amazon EC2 instances during demand spikes to maintain performance and decrease capacity during lulls to reduce costs.

C is the correct answer.

A is correct https://docs.aws.amazon.com/autoscaling/ec2/userguide/what-is-amazon-ec2-auto-scaling.html