AWS Compute and Storage Services 5 — Questions and Answers
Question 1: Which AWS compute service enables running HPC workloads with tightly coupled, low-latency networking using Elastic Fabric Adapter (EFA)?
- AWS Fargate
- Amazon EC2 with EFA-supported instance types (Correct answer)
- AWS Batch on Lambda
- Amazon Lightsail
Correct answer: Amazon EC2 with EFA-supported instance types
Elastic Fabric Adapter (EFA) is a network interface for EC2 instances that provides low-latency, high-bandwidth communication required by HPC and ML training workloads.
Question 2: What is the difference between an EC2 instance store and an EBS volume?
- Instance store persists after instance termination; EBS does not
- EBS provides persistent storage; instance store is ephemeral and lost when the instance stops or terminates (Correct answer)
- Instance store is network-attached; EBS is physically on the host
- EBS cannot be detached; instance store can be moved between instances
Correct answer: EBS provides persistent storage; instance store is ephemeral and lost when the instance stops or terminates
EBS volumes are durable network-attached storage that persists independently, while instance store volumes are physically attached to the host and lost when the instance stops or terminates.
Question 3: A team needs to copy S3 objects from a bucket in us-east-1 to a bucket in eu-west-1 automatically whenever new objects are added. Which feature handles this?
- S3 Lifecycle policies
- S3 Cross-Region Replication (CRR) (Correct answer)
- S3 Transfer Acceleration
- AWS DataSync
Correct answer: S3 Cross-Region Replication (CRR)
S3 Cross-Region Replication (CRR) automatically replicates new objects from a source bucket to a destination bucket in a different AWS Region.
Question 4: Which EC2 Auto Scaling policy type adds or removes a fixed number of instances based on a CloudWatch alarm threshold?
- Target Tracking Scaling
- Step Scaling (Correct answer)
- Predictive Scaling
- Scheduled Scaling
Correct answer: Step Scaling
Step Scaling adjusts capacity by a defined number of instances in steps based on the magnitude of a CloudWatch alarm breach.
Question 5: An application requires block storage with 64,000 IOPS and sub-millisecond latency for a critical Oracle database. Which EBS volume type should be used?
- gp3
- st1
- io2 Block Express (Correct answer)
- sc1
Correct answer: io2 Block Express
io2 Block Express supports up to 256,000 IOPS and sub-millisecond latency, making it ideal for latency-sensitive, high-performance databases.
Question 6: What AWS feature enables an EC2 instance to assume an IAM role and access other AWS services without embedding credentials in the application code?
- AWS Secrets Manager
- IAM Instance Profile (Correct answer)
- AWS STS AssumeRole via static keys
- EC2 Key Pairs
Correct answer: IAM Instance Profile
An IAM Instance Profile attaches an IAM role to an EC2 instance, allowing the instance to automatically obtain temporary credentials via the metadata service.
Question 7: Which S3 feature protects against accidental deletion by keeping multiple versions of an object, including all writes and deletes?
- S3 Object Lock
- S3 Versioning (Correct answer)
- S3 MFA Delete only
- S3 Replication
Correct answer: S3 Versioning
S3 Versioning retains all versions of every object, allowing recovery from accidental deletions or overwrites by restoring a previous version.
AWS Compute and Storage Services 5
Which AWS compute service enables running HPC workloads with tightly coupled, low-latency networking using Elastic Fabric Adapter (EFA)?