Wrong Question

[Jonathan Barbosa]

Category: SOA-C02 – Deployment, Provisioning, and Automation

A leading telecommunications company has a hybrid cloud architecture that runs its online services. In order to optimize the use of their cloud resources and to save costs, your manager requested for you to analyze their existing architecture and perform the necessary tasks to make it cost-effective.

Which of the following options will help reduce your costs on your AWS usage? (Select TWO.)

– Reduce the use of Elastic IPs that are attached to running EC2 instances.

– Consider deleting idle EBS volumes which are not attached to any EC2 instances.

– Refrain from using Auto Scaling Groups as they incur additional cost.

– Consider purchasing Reserved EC2 instances for specific workloads which are expected to run continuously for more than a year.

– Consider moving your EC2 instances to the same AZ since data transferred between AZs is considered billable for “regional data transfer”.

Correct options are Consider deleting idle EBS volumes which are not attached to any EC2 instances. and Consider purchasing Reserved EC2 instances for specific workloads which are expected to run continuously for more than a year.

But the options Consider moving your EC2 instances to the same AZ since data transferred between AZs is considered billable for “regional data transfer”. is correct too data transferred in the same region cross-azs are billable.

https://aws.amazon.com/pt/blogs/architecture/overview-of-data-transfer-costs-for-common-architectures/
https://docs.aws.amazon.com/cur/latest/userguide/cur-data-transfers-charges.html

Workload components in same AWS Region

Data transfer within the same Availability Zone is free. One way to achieve high availability for a workload is to deploy in multiple Availability Zones.

Consider a workload with two application servers running on Amazon EC2 and a database running on Amazon Relational Database Service (Amazon RDS) for MySQL (Figure 3). For high availability, each application server is deployed into a separate Availability Zone. Here, data transfer charges apply for cross-Availability Zone communication between the EC2 instances. Data transfer charges also apply between Amazon EC2 and Amazon RDS. Consult the Amazon RDS for MySQL pricing guide for more information.

[JR-TutorialsDojo]

Hello Jonathan Barbosa,

Thank you for the feedback.

It’s true that moving data between Availability Zones (AZs) within the same AWS Region incurs costs that fall under the UsageType called Region-DataTransfer-Regional-Bytes. However, the reason this particular option wasn’t selected as a correct answer is due to the inaccurate use of AWS terminology in the phrasing. The option refers to this as “regional data transfer,” which typically refers to inter-region transfers, not cross-AZ traffic within the same Region

The Option States:

Consider moving your EC2 instances to the same AZ since data transferred between AZs is considered billable for “regional data transfer”.

This option mixes terms inaccurately:

It talks about data transfer between Availability Zones, which is real and billable. However, it then refers to it as “regional data transfer,” which in AWS terminology typically refers to data transferred between Regions, not availability zones (AZs).

I hope this helps! Please let us know if you need further assistance.

Regards,
JR @ Tutorials Dojo