AWS Certified Advanced Networking Specialty Practice Exam

Which factor affects high availability for AWS applications most significantly?

1. Using single instance deployments

2. Implementing redundancy across Availability Zones

3. Utilizing long-distance connectivity options

4. Relying on manual scaling processes

The correct answer is: Implementing redundancy across Availability Zones

Implementing redundancy across Availability Zones is crucial for ensuring high availability in AWS applications. When you deploy your application across multiple Availability Zones, you benefit from physical separation of resources, which means that even if one zone experiences issues such as power outages or other failures, the other zones can continue to operate normally. This design enhances fault tolerance and reliability, allowing the application to maintain performance and availability even in the face of localized disruptions. Additionally, leveraging multiple Availability Zones allows for load balancing and distribution of traffic, further optimizing performance and reducing the risk of service outages. AWS recommends this strategy as a best practice for building resilient applications, making it a foundational aspect of architecting for high availability in the cloud environment. In contrast, options such as single instance deployments, long-distance connectivity, and manual scaling processes lack the inherent resilience that redundancy across Availability Zones provides, thereby significantly increasing the risk of application downtime in the event of failures or traffic surges.