AWS Certified SysOps Administrator – Associate (legacy) — Question 615

A sysops administrator set up an Amazon ElastiCache for Memcached cluster for an application. During testing, the application experiences increased latency.
Amazon CloudWatch metrics for the Memcached cluster show CPUUtilization is consistently above 95% and FreeableMemory is consistently under 1 MB.
Which action will solve the problem?

Answer options

• A. Configure ElastiCache automatic scaling for the Memcached cluster. Set the CPUUtilization metrics as a scaling trigger above 75% and FreeableMemory below 10 MB.
• B. Configure ElastiCache read replicas for each Memcached node in different Availability Zones to distribute the workload.
• C. Deploy an Application Load Balancer to distribute the workload to Memcached cluster nodes.
• D. Replace the Memcached cluster and select a node type that has a higher CPU and memory.

Correct answer: D

Explanation

The CloudWatch metrics indicate that the Memcached cluster is experiencing severe resource exhaustion in both CPU and memory. Unlike Redis, Memcached does not support read replicas, and Application Load Balancers cannot be used to distribute traffic directly to Memcached nodes. Vertically scaling the cluster by replacing it with a larger node type with more CPU and memory is the correct way to resolve both bottlenecks.