Q75 — AWS ANS-C01 Ch.1

Question 75 of 100 | ← Chapter 1

A network engineer needs to design the architecture for a high performance computing (HPC) workload. Amazon EC2 instances will require 10 Gbps flows and an aggregate throughput of up to 100 Gbps across many instances with low-latency communication. Which architecture solution will optimize this workload?

• A. Place nodes in a single subnet of a VPC. Configure a cluster placement group. Ensure that the latest Elastic Fabric Adapter (EFA) drivers Are installed on the EC2 instances with a supported operating system. ✓
• B. Place nodes in multiple subnets in a single VPC. Configure a spread placement group. Ensure that the EC2 instances support Elastic Network Adapters (ENAs) and that the drivers are updated on each instance operating system.
• C. Place nodes in multiple VPCs Use AWS Transit Gateway to route traffic between the VPCs. Ensure that the latest Elastic Fabric Adapter (EFA) drivers are installed on the EC2 instances with a supported operating system.
• D. Place nodes in multiple subnets in multiple Availability Zones. Configure a cluster placement group. Ensure that the EC2 instances support Elastic Network Adapters (ENAs) and that the drivers are updated on each instance operating system.

Correct Answer: A. Place nodes in a single subnet of a VPC. Configure a cluster placement group. Ensure that the latest Elastic Fabric Adapter (EFA) drivers Are installed on the EC2 instances with a supported operating system.

Explanation

Amazon EC2实例的高性能计算（HPC）场景需满足低延迟、高吞吐需求。集群置放组（Cluster Placement Group）将实例紧密部署于同一可用区，减少网络延迟，提升节点间通信性能。弹性结构适配器（EFA）支持OS-bypass功能，适合HPC及机器学习场景的直接内存访问需求，而ENA侧重常规高性能网络。单子网设计避免了跨子网或跨可用区的延迟及带宽损耗。AWS文档指出，EFA配合集群置放组适用于需要节点间紧密耦合的应用，如HPC（来源：AWS EFA和置放组官方文档）。选项B的分散置放组无法满足低延迟，选项C/D的跨VPC或多可用区架构增加网络复杂度。