Question

A user possesses a VPC that is built in a single region. At the moment, it requires two AZs. In this VPC, the user has employed a very significant two-tier web application. The web application utilizes ELB and auto scaling. Further, the application relies on synchronous replication, which needs very low latency connectivity to the database. The application is required to remain completely accessible even if any one of the application's AZs goes down, and Auto Scaling cannot launch new instances in the remaining AZs. What measures can be adopted to enhance the current architecture to ensure this? SELECT THE CORRECT ANSWER

A. Implement Multi-AZ RDS for database redundancy.
B. Deploy multiple instances of the database in each AZ for failover.
C. Use Elastic Load Balancing (ELB) to distribute traffic across multiple regions.
D. Configure a separate VPC in another region for disaster recovery.

Answer 1

To enhance the current architecture and ensure high availability for the two-tier web application when one AZ goes down and Auto Scaling cannot launch new instances, the user should implement Multi-AZ RDS for database redundancy.

Step-by-step explanation:

To ensure that the two-tier web application remains accessible even if one AZ goes down and Auto Scaling cannot launch new instances in the remaining AZs, the user can implement Multi-AZ RDS for database redundancy. By deploying the database in multiple AZs, the application can continue to function and replicate data synchronously without any downtime. This ensures that the database remains highly available and can handle failover in case of AZ failure.

Using Elastic Load Balancing (ELB) to distribute traffic across the AZs is already a part of the existing architecture, which helps achieve high availability for the web application. However, to enhance this architecture further, implementing Multi-AZ RDS for database redundancy is necessary.

Deploying a separate VPC in another region for disaster recovery is another option, but it may not be the most cost-effective solution if the primary concern is maintaining low latency connectivity to the database. It can be considered as an additional measure for high availability, but implementing Multi-AZ RDS should be the primary solution.