Exam AWS Certified Solutions Architect - Associate SAA-C03 topic 1 question 244 discussion

C. Move the database to Amazon Aurora with a read replica in another Availability Zone. Create an Amazon Machine Image (AMI) from the EC2 instance. Configure an Application Load Balancer in two Availability Zones. Attach an Auto Scaling group that uses the AMI across two Availability Zones. This approach will provide both high availability and scalability for the website platform. By moving the database to Amazon Aurora with a read replica in another availability zone, it will provide a failover option for the database. The use of an Application Load Balancer and an Auto Scaling group across two availability zones allows for automatic scaling of the website to meet increased user demand. Additionally, creating an AMI from the original EC2 instance allows for easy replication of the instance in case of failure.

C is the only option via deduction logic based on the assumption the CMS database is Aurora compatible. Other solutions don't promise scaling as much as Aurora solution in option C does.

A and B involve manual steps and do not include scaling (it's just two fixed instances) D scales the application part but leaves the database on a single EC2 instance which would be neither "highly available" nor "scaleable"

C. Move the database to Amazon Aurora with a read replica in another Availability Zone. Create an Amazon Machine Image (AMI) from the EC2 instance. Configure an Application Load Balancer in two Availability Zones. Attach an Auto Scaling group that uses the AMI across two Availability Zones.

Move the database to Amazon Aurora with a read replica in another Availability Zone. Create an Amazon Machine Image (AMI) from the EC2 instance. Configure an Application Load Balancer in two Availability Zones. Attach an Auto Scaling group that uses the AMI across two Availability Zones.

C. Move the database to Amazon Aurora with a read replica in another Availability Zone. Create an Amazon Machine Image (AMI) from the EC2 instance. Configure an Application Load Balancer in two Availability Zones. Attach an Auto Scaling group that uses the AMI across two Availability Zones.

The question does not say if the current application is using a relational database, so how we can be sure that it can moved to RDS or aurora as answers A, B & C states? In my opinion the right answer is D.

has all options needed for HA

Option A does not provide a solution for high availability or scalability. Manually launching another EC2 instance in the same AZ may not ensure high availability, as a failure in that AZ would result in downtime. Option B improves database performance and provides a level of fault tolerance, it does not address the scalability aspect of the website platform. Option C provides both high availability and fault tolerance. Creating an AMI allows for easy replication of the EC2 instance across AZs. Configuring an ALB in two AZs and attaching an ASG ensures scalability and load distribution across multiple instances. Option D does not provide the high availability and scalability required by the company. Scheduled backups to S3 address data protection but do not contribute to website availability or scalability.

Option C meets the requirements.

Why not D? Are we just assuming that there will be no write to the db?

Absolutely C.

C: This will allow the website platform to be highly available by using Aurora, which provides automatic failover and replication. Additionally, by creating an AMI from the original EC2 instance, the Auto Scaling group can automatically launch new instances in multiple availability zones and use the Application Load Balancer to distribute traffic across them. This way, the website will be able to handle the increased traffic, and will be less likely to go down due to a single point of failure.