A research institution stores two types of data in a single Amazon S3 bucket using differe… — AWS Certified Solutions Architect - Associate

A research institution stores two types of data in a single Amazon S3 bucket using different prefixes:

* Genomic Sequence Datasets (stored under the `genomics/` prefix): The average file size is $250\text{ MB}$ . These files are accessed frequently during the first 35 days after creation. After 35 days, they are rarely accessed but must be retained for $10\text{ years}$ for regulatory compliance. When access is required, the datasets must be retrievable within minutes.
* Intermediate Pipeline Run Logs (stored under the `logs/` prefix): The average file size is $10\text{ KB}$ . These files are only needed for debugging within the first 14 days of creation, after which they can be permanently deleted.

Which combination of actions will meet these requirements in the most cost-effective manner? (Select TWO.)

Create a lifecycle rule for the `genomics/` prefix to transition the objects to Amazon S3 Glacier Flexible Retrieval after 35 days.Answer
B
Create a lifecycle rule for the `logs/` prefix to transition the objects to Amazon S3 Standard-Infrequent Access (S3 Standard-IA) after 7 days.
Create a lifecycle rule for the `logs/` prefix to expire the objects after 14 days.Answer
D
Create a lifecycle rule for the `genomics/` prefix to transition the objects to Amazon S3 Glacier Deep Archive after 35 days.
E
Create a lifecycle rule for the `logs/` prefix to transition the objects to Amazon S3 One Zone-Infrequent Access (S3 One Zone-IA) after 7 days.

Answer

Transitioning the genomic datasets to Amazon S3 Glacier Flexible Retrieval after 35 days, and expiring the pipeline run logs after 14 days directly from S3 Standard.

Transitioning the genomic datasets to Amazon S3 Glacier Flexible Retrieval after 35 days is the most cost-effective option because it matches the 10-year retention requirement, and the Glacier Flexible Retrieval class supports Expedited retrievals, which can return objects within 1 to 5 minutes, satisfying the requirement to retrieve data within minutes. Expiring the pipeline run logs after 14 days directly from S3 Standard is the most cost-effective option for that prefix because the average file size is

10\text{ KB}

(well below the

128\text{ KB}

minimum billing size for Infrequent Access tiers) and the retention period is only 14 days (well below the 30-day minimum billing duration). Transitioning these logs to S3 Standard-IA or S3 One Zone-IA would incur significant cost penalties due to minimum storage size and duration constraints.

Step-by-Step Solution

Analyze the access pattern and size of the genomic sequence datasets.

The datasets are large (

250\text{ MB}

), accessed frequently for 35 days, then rarely accessed for 10 years, and must be retrievable within minutes.

To identify the correct storage class that supports minutes-level retrieval and has low storage cost for long-term retention.

Evaluate S3 Glacier tiers for the genomic sequence datasets.

Amazon S3 Glacier Flexible Retrieval supports Expedited retrieval (1-5 minutes) and has low cost for 10-year retention, whereas Glacier Deep Archive takes at least 12 hours.

To select the most cost-effective tier that meets the minutes-level retrieval constraint.

Analyze the access pattern, size, and retention requirements of the intermediate pipeline run logs.

The logs are small (

10\text{ KB}

), only needed for 14 days, and then can be deleted.

To determine if transitioning to an Infrequent Access or Archive tier is financially beneficial.

Calculate potential penalties for transitioning the logs to S3 Standard-IA or S3 One Zone-IA.

Transitioning to IA classes would charge for

128\text{ KB}

instead of

10\text{ KB}

, and deleting after 14 days would trigger early deletion fees for the 30-day minimum duration.

To verify that keeping the logs in S3 Standard and expiring them after 14 days is the most cost-effective strategy.

Key Concept

Cost-optimized storage tiering depends on understanding minimum object sizes, minimum storage durations, and retrieval times across S3 storage classes.

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Answer

Step-by-Step Solution

Key Concept

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