Exam AWS Certified Solutions Architect - Associate SAA-C03 topic 1 question 69 discussion

By configuring the Auto Scaling group to use multiple Availability Zones, the application will be able to continue running even if one Availability Zone goes down. Configuring the database as Multi-AZ will also ensure that the database remains available in the event of a failure in one Availability Zone. Using an Amazon RDS Proxy instance for the database will allow the application to automatically route traffic to healthy database instances, further increasing the availability of the application. This solution will meet the requirements for high availability with minimal operational effort.

RDS Proxy for Aurora https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/rds-proxy.html

Ans B - good explanation by SilentMilli (1yr 8mth ago). The database Proxy is key.

Keyword - Higly available Use multiple availability zones

A: Different region doesn't help C: Would have made sense if it wasn't restricting to one AZ. D: Regions + S3 + Lambda = Operational effort extreme B: Although not entirely sure how RDS Proxy helps because it is for connection pooling but it is the only workable solution using multi AZ

The company wants to minimize costs and is willing to accept slower traffic if the primary connection fails, it may be tempted to choose a VPN connection as a backup, in which case the answer is A. Cost-Effectiveness: VPN connections are generally more economical than AWS Direct Connect, especially for low to moderate bandwidth needs. Backup connection: A VPN connection can serve as a more cost-effective backup if the primary Direct Connect connection fails, even if it may be slower. Acceptance of slower traffic: The question clearly states that the company is willing to accept slower traffic if the primary connection fails, which implies a tolerance for connection speeds.

ASG and MultiAZ is the best answer

B is the right answer

Option B requires the least operational effort to meet the high availability and minimum downtime/data loss requirements. The key points are: Use an Auto Scaling group across multiple AZs for high availability of the EC2 instances. Configure the Aurora DB as Multi-AZ for high availability, automatic failover, and minimum data loss. Use RDS Proxy for connection pooling to the DB for performance

Highly available, Minimum downtime and Minimum loss of data = Auto Scaling group on Multi-AZ, Database on Multi-AZ, Amazon RDS Proxy.

Option B is the right answer.

B is correct answer

A. This approach provides geographic redundancy, it introduces additional complexity and operational effort, including managing replication, handling latency, and potentially higher data transfer costs. C. While snapshots can be used for data backup and recovery, they do not provide real-time failover capabilities and can result in significant data loss if a failure occurs between snapshots. D. While this approach offers some decoupling and scalability benefits, it adds complexity to the data flow and introduces additional overhead for data processing. In comparison, option B provides a simpler and more streamlined solution by utilizing multiple AZs, Multi-AZ configuration for the database, and RDS Proxy for improved connection management. It ensures high availability, minimal downtime, and minimum loss of data with the least operational effort.

@Wajif the reason why it's not A is because the question mentions High availability and nothing to do with region. You can achieve HA without spanning multiple regions. Also B is incorrect because ALB are region specific and span across multiple AZ with that specific region (not cross region)

RDS Proxy is fully managed by AWS for RDS/Aurora. It is auto-scaling and highly available by default.

The correct solution is B: Configure the Auto Scaling group to use multiple Availability Zones. Configure the database as Multi-AZ. Configure an Amazon RDS Proxy instance for the database. This solution will meet the requirements of high availability with minimum downtime and minimum loss of data with the least operational effort. By configuring the Auto Scaling group to use multiple Availability Zones, the web application will be able to withstand the failure of one Availability Zone without any disruption to the service. By configuring the database as Multi-AZ, the database will automatically failover to a standby instance in a different Availability Zone in the event of a failure, ensuring minimal downtime. Additionally, using an RDS Proxy instance will help to improve the performance and scalability of the database.

Aurora PostgreSQL DB clusters don't support Aurora Replicas in different AWS Regions https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/AuroraPostgreSQL.Replication.html