DEA-C01 Practice Test 6 — 10 Questions

Question 1

Refer to the exhibit. A data engineer has attached this bucket policy to an S3 bucket named data-lake-bucket. The engineer wants to allow only GET requests from the corporate network (10.0.0.0/16) over HTTPS. However, users report that they cannot access objects even when connected to the corporate network. What is the issue?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

The Deny statement blocks all requests that are not using HTTPS, including those from the corporate network.. The Deny statement with `aws:SecureTransport` set to `false` blocks all HTTP requests. Since the Allow statement only permits GET requests from the corporate network (10.0.0.0/16) but does not require HTTPS, any request from that network that uses HTTP is denied by the explicit Deny. The Deny statement overrides the Allow, so even legitimate corporate users are blocked if they use HTTP.

Answer

The Deny statement should include a condition on the source IP.

Answer

The Allow statement should include a condition for SecureTransport.

Answer

The Allow statement should specify s3:GetObject instead of s3:GetObject.

Question 2

A data engineer needs to transfer 10 TB of data from an on-premises Hadoop cluster to Amazon S3. The network bandwidth is limited to 100 Mbps, and the transfer must be completed within 48 hours. Which solution meets the requirements?

Accepted Answer

Use AWS Snowball Edge device to transfer data offline. The on-premises Hadoop cluster has 10 TB of data to transfer, but the network bandwidth is only 100 Mbps. At 100 Mbps, the theoretical maximum transfer rate is about 12.5 MB/s, which would take approximately 10 TB / 12.5 MB/s ≈ 800,000 seconds ≈ 222 hours — far exceeding the 48-hour window. AWS Snowball Edge is an offline, physical device that bypasses network constraints entirely, allowing you to transfer the data by shipping the device, which completes within days regardless of bandwidth.

Answer

Use AWS DataSync to transfer data online

Answer

Use S3 Transfer Acceleration over the internet

Answer

Set up AWS Direct Connect to increase bandwidth

Question 3

A data engineer needs to monitor Amazon DynamoDB table metrics to detect throttled requests. Which CloudWatch metric should the engineer set an alarm on?

Accepted Answer

ThrottledRequests. `ThrottledRequests` is the specific Amazon CloudWatch metric that tracks the number of requests to a DynamoDB table that are throttled due to exceeding the provisioned throughput capacity. This metric directly reflects throttling events, making it the appropriate choice for setting an alarm to detect throttled requests.

Answer

ReadThrottleEvents

Answer

SuccessfulRequestLatency

Answer

ConsumedWriteCapacityUnits

Question 4

A data engineer is monitoring a Redshift cluster that is experiencing slow query performance. The cluster has 4 dc2.large nodes. The engineer notices that disk space usage is at 85% across all nodes. Which action would MOST likely improve query performance?

Accepted Answer

Increase the number of nodes to 8.. At 85% disk usage on dc2.large nodes, the cluster is approaching the threshold where Redshift begins to automatically offload data to Amazon S3, causing significant performance degradation due to increased I/O and network latency. Adding more nodes (option C) increases both compute capacity and total disk space, reducing per-node disk pressure and allowing the cluster to keep more data local for faster query execution.

Answer

Change the table design to use DISTKEY and SORTKEY.

Answer

Enable compression on all columns.

Answer

Run the VACUUM command to reclaim space.

Question 5

A company wants to audit all data access events in their S3 buckets, including who accessed objects and from which IP address. Which AWS service should be used to capture these events?

Accepted Answer

AWS CloudTrail with data events enabled. AWS CloudTrail can log S3 API calls such as GetObject, PutObject, and ListObjects when data events are enabled, capturing details like who accessed an object and from which IP address. Option D is incorrect because S3 Server Access Logs provide object-level logs but do not include IAM user or role details. Option B is incorrect because Amazon CloudWatch Logs can store and monitor logs but does not capture S3 data events directly. Option C is incorrect because AWS Config records resource configuration changes, not data access events.

Answer

Amazon CloudWatch Logs

Answer

AWS Config

Answer

Amazon S3 Server Access Logs

Question 6

A company needs to ingest data from a relational database into Amazon S3 for analytics. The database is an Amazon RDS MySQL instance. Which AWS service should be used for a one-time historical data load?

Accepted Answer

AWS Database Migration Service (DMS). AWS Database Migration Service (DMS) is the correct choice for a one-time historical data load from Amazon RDS MySQL to Amazon S3. DMS supports full-load migrations from relational databases to S3, making it ideal for this use case. AWS Glue ETL can also perform similar tasks but is more suited for complex transformations and scheduled jobs, and DMS is the dedicated service for database migrations. Amazon Athena is a query service, not an ingestion tool. Amazon Kinesis Data Firehose is designed for streaming data, not one-time loads.

Answer

AWS Glue ETL

Answer

Amazon Athena

Answer

Amazon Kinesis Data Firehose

Question 7

A company uses AWS Lake Formation to manage data lake permissions. A data analyst cannot query a table in Athena, although the table appears in the catalog. The analyst has IAM permissions to run Athena. What is the MOST likely cause?

Accepted Answer

The analyst lacks Lake Formation permissions on the table.. Lake Formation permissions are separate from IAM; even if the analyst has IAM permissions to run Athena, they also need specific Lake Formation permissions (e.g., SELECT) on the table to query it. The table appears in the catalog because the analyst has DESCRIBE permission on the database or table, but querying requires additional data access permissions. Option A is incorrect because the table appears in the catalog, so it is registered. Option B is incorrect because the S3 bucket policy might allow access, but Lake Formation can override it. Option D is incorrect because the workgroup output location affects where query results are stored, not the ability to query a specific table.

Answer

The Glue Data Catalog does not have the table registered.

Answer

The S3 bucket policy denies access to the analyst's IAM role.

Answer

The Athena workgroup is not configured with the correct output location.

Question 8

A data engineer needs to transform CSV files in S3 to Parquet format using a serverless solution. The files are large (up to 5 GB each) and arrive irregularly. Which TWO services can accomplish this with minimal operational overhead? (Choose TWO.)

Accepted Answer

AWS Glue ETL job. AWS Glue ETL job is correct because it is a fully managed, serverless service that can automatically convert CSV to Parquet without provisioning infrastructure. It handles large files (up to 5 GB) by scaling Spark executors dynamically, and can be triggered by S3 events for irregular arrivals, minimizing operational overhead.

Answer

Amazon EC2 with a script

Answer

Amazon EMR cluster

Answer

Amazon Redshift Spectrum

Question 9

A data engineering team is ingesting data from multiple sources into Amazon S3 using AWS Glue ETL jobs. The jobs are failing intermittently with the error: 'Task ran out of memory'. The input data size varies widely from 100 MB to 10 GB per job. Which configuration change would best mitigate this issue?

Accepted Answer

Enable job bookmarking to process only incremental data. Enabling job bookmarking allows the Glue ETL job to process only incremental (new or changed) data, which directly addresses the intermittent out-of-memory errors caused by widely varying input sizes (100 MB to 10 GB). By skipping previously processed data, the job consistently handles smaller data volumes per run, reducing memory pressure on the Spark executors.

Answer

Increase the number of workers in the Glue job

Answer

Reduce the batch size in the S3 source node

Answer

Change the job type from Spark to Python shell

Question 10

A company is streaming data from an application to Amazon Kinesis Data Streams. The data must be transformed in real time and then stored in Amazon S3 in Parquet format. Which AWS service should be used for the transformation step?

Accepted Answer

Amazon Kinesis Data Analytics for Apache Flink.. Amazon Kinesis Data Analytics for Apache Flink is a serverless service that can run Apache Flink applications to perform real-time transformations on streaming data. Option A (Amazon Kinesis Data Firehose with a Lambda transformation) is primarily for loading data and has limitations for complex transformations. Option B (Amazon EMR running Apache Spark Streaming) can work but adds management overhead and is not the simplest managed service. Option D (AWS Lambda with a Kinesis trigger) is suitable for lightweight transformations but may hit execution time limits for complex or long-running transformations.

Answer

Amazon Kinesis Data Firehose with a Lambda transformation.

Answer

Amazon EMR running Apache Spark Streaming.

Answer

AWS Lambda with a Kinesis trigger.