A large financial services company uses Amazon ElastiCache (Redis OSS) for its new application that has a global user base. A solutions architect must develop a caching solution that will be available across AWS Regions and include low-latency replication and failover capabilities for disaster recovery (DR). The company's security team requires the encryption of cross-Region data transfers. Which solution meets these requirements with the LEAST amount of operational effort?

Amazon ElastiCache for Redis Global Datastore is a feature specifically designed to meet these requirements. It provides a fully managed, fast, and secure solution for replicating a Redis cluster across multiple AWS Regions. This feature enables low-latency global reads and disaster recovery by allowing a secondary cluster in another Region to be promoted to primary with minimal downtime. All cross-Region traffic within a Global Datastore is encrypted, fulfilling the security requirement. This managed service approach represents the least operational effort compared to manual replication or backup-and-restore methods.

A. Using AWS Database Migration Service (AWS DMS) for cache replication is not a standard pattern and introduces significant operational complexity, contradicting the "least effort" requirement.

C. This option is incorrect for the same reason as option A; AWS DMS is not the appropriate tool for low-latency cache replication and adds unnecessary operational overhead.

D. A snapshot-and-restore strategy is a valid disaster recovery method but does not provide low-latency replication. This approach leads to a higher Recovery Point Objective (RPO).

1. AWS ElastiCache User Guide for Redis: "Replication Across AWS Regions Using Global Datastore" - This section details that Global Datastore is designed for "fully managed

fast

reliable

and secure cross-region replication." It explicitly states its use for "low latency global reads and disaster recovery."

2. AWS ElastiCache User Guide for Redis: "Disaster Recovery with Global Datastore" - This page describes the process of promoting a secondary cluster to primary in a disaster recovery scenario

highlighting the managed failover capability. It notes

"In the unlikely event of regional degradation

one of the healthy secondary clusters can be promoted to become the new primary with full read/write capabilities."

3. AWS ElastiCache User Guide for Redis: "Encryption in Transit" - This section confirms that for Global Datastore

"All inter-region traffic between the clusters is encrypted." This directly addresses the security requirement in the question.