SAP-C02 · Question #735
A solutions architect must implement a multi-Region architecture for an Amazon RDS for PostgreSQL database that supports a web application. The database launches from an AWS CloudFormation template…
The correct answer is A. Create a cross-Region read replica of the database in the secondary Region. Configure an AWS D. Create a failover routing policy in Route 53 for the database DNS record. Set the primary and. To meet the RTO of 15 minutes and RPO of 2 hours for a multi-Region RDS PostgreSQL database, a cross-Region read replica should be established in the secondary Region. This read replica provides replicated data for low RPO. For fast failover and RTO, Amazon Route 53 should be…
Question
A solutions architect must implement a multi-Region architecture for an Amazon RDS for PostgreSQL database that supports a web application. The database launches from an AWS CloudFormation template that includes AWS services and features that are present in both the primary and secondary Regions. The database is configured for automated backups, and it has an RTO of 15 minutes and an RPO of 2 hours. The web application is configured to use an Amazon Route 53 record to route traffic to the database. Which combination of steps will result in a highly available architecture that meets all the requirements? (Choose two.)
Options
- ACreate a cross-Region read replica of the database in the secondary Region. Configure an AWS
- BIn the primary Region, create a health check on the database that will invoke an AWS Lambda
- CCreate an AWS Lambda function to copy the latest automated backup to the secondary Region
- DCreate a failover routing policy in Route 53 for the database DNS record. Set the primary and
- ECreate a hot standby database in the secondary Region. Use an AWS Lambda function to restore
How the community answered
(25 responses)- A80% (20)
- B4% (1)
- C12% (3)
- E4% (1)
Why each option
To meet the RTO of 15 minutes and RPO of 2 hours for a multi-Region RDS PostgreSQL database, a cross-Region read replica should be established in the secondary Region. This read replica provides replicated data for low RPO. For fast failover and RTO, Amazon Route 53 should be configured with a failover routing policy that points to the primary database and automatically switches to the promoted read replica in the secondary Region upon detection of a primary failure.
Creating a cross-Region read replica ensures that a continuously updated copy of the database exists in the secondary Region, providing a low RPO (easily meeting 2 hours) and a readily available instance for promotion to a new primary during failover, which is critical for meeting the RTO.
While health checks are important, a Lambda function to invoke a custom failover might be complex and less reliable than Route 53's native failover capabilities when integrated with a read replica promotion.
Copying automated backups to the secondary Region and restoring from them typically takes significantly longer than promoting a cross-Region read replica, making it difficult to meet the 15-minute RTO.
A Route 53 failover routing policy, coupled with health checks, automatically updates the database DNS record to point to the secondary Region's (promoted) database when the primary becomes unhealthy, enabling the web application to quickly reconnect and achieve the 15-minute RTO.
A "hot standby" likely refers to a read replica, but using a Lambda function to *restore* it rather than *promote* it is an inefficient and slower approach that may not meet the RTO.
Concept tested: Amazon RDS Multi-Region Disaster Recovery (Read Replicas & Route 53 Failover)
Source: https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Concepts.PostgreSQL.html#PostgreSQL.Replication.CrossRegion
Community Discussion
No community discussion yet for this question.