A biotechnology company runs clinical trial data pipelines and stores two types of files i… — AWS Certified Solutions Architect - Associate

A biotechnology company runs clinical trial data pipelines and stores two types of files in an Amazon S3 bucket:

* Raw DNA Sequencing Outputs: Average file size is $250\text{ MB}$ . These files are accessed frequently during the first $14\text{ days}$ of analysis, accessed occasionally for the next $10\text{ days}$ (Days $15\text{--}24$ ), and then rarely accessed but must be preserved for $3\text{ years}$ to meet regulatory requirements. Retrieval within $12\text{ hours}$ is acceptable.
* Pipeline Execution Metadata Logs: Average file size is $65\text{ KB}$ . These files are accessed frequently during the first $7\text{ days}$ for execution verification and are no longer needed afterward, but must be deleted after a total of $25\text{ days}$ for security compliance.

Which S3 lifecycle configuration is the most cost-effective for these requirements?

Transition the raw DNA sequencing outputs directly from S3 Standard to S3 Glacier Deep Archive on Day 24, and configure the pipeline execution metadata logs to be deleted from S3 Standard on Day 25 without any transition.Answer
B
Transition the raw DNA sequencing outputs to S3 Standard-IA on Day 14, transition them to S3 Glacier Deep Archive on Day 24, and transition the pipeline execution metadata logs to S3 Standard-IA on Day 7 before deleting them on Day 25.
C
Transition the raw DNA sequencing outputs to S3 Standard-IA on Day 14, transition them to S3 Glacier Flexible Retrieval on Day 24, and configure the pipeline execution metadata logs to be deleted from S3 Standard on Day 25 without any transition.
D
Transition the raw DNA sequencing outputs directly from S3 Standard to S3 Glacier Deep Archive on Day 24, and transition the pipeline execution metadata logs to S3 Standard-IA on Day 7 before deleting them on Day 25.

Answer

The most cost-effective S3 lifecycle configuration transitions the raw DNA sequencing outputs directly from S3 Standard to S3 Glacier Deep Archive on Day 24, and deletes the pipeline execution metadata logs directly from S3 Standard on Day 25 without transition.

The correct answer identifies that transitioning the raw DNA sequencing outputs directly from S3 Standard to S3 Glacier Deep Archive on Day 24 avoids the

30\text{-day}

minimum duration storage penalty associated with S3 Standard-IA. It also correctly determines that keeping the

65\text{ KB}

metadata logs in S3 Standard and deleting them on Day 25 is more economical than transitioning them to S3 Standard-IA, as they are below the

128\text{ KB}

minimum billing size and would be deleted before the

30\text{-day}

minimum storage duration of S3 Standard-IA.

Step-by-Step Solution

Analyze the lifecycle requirements of the

250\text{ MB}

Raw DNA Sequencing Outputs.

Transitioning these files to S3 Standard-IA on Day 14 and then to S3 Glacier Deep Archive on Day 24 means they spend only

10\text{ days}

in S3 Standard-IA. This violates the

30\text{-day}

minimum storage duration of S3 Standard-IA, resulting in a billing penalty for the remaining

20\text{ days}

. Keeping them in S3 Standard until Day 24 and transitioning directly to S3 Glacier Deep Archive avoids this penalty and aligns with the

12\text{-hour}

retrieval window.

To identify the most cost-optimal transition path while satisfying retrieval time and retention requirements.

Analyze the lifecycle requirements of the

65\text{ KB}

Pipeline Execution Metadata Logs.

Since these logs are

65\text{ KB}

(which is less than the

128\text{ KB}

minimum storage size limit of S3 Standard-IA) and are deleted on Day 25 (which is less than the

30\text{-day}

minimum storage duration of S3 Standard-IA), transitioning them to S3 Standard-IA would result in double penalties (paying for

128\text{ KB}

size and paying for a full

30\text{ days}

of storage). Keeping them in S3 Standard until deletion is cheaper.

To prevent S3 Standard-IA size and duration billing penalties on small transient files.

Combine the evaluations to select the optimal configuration.

Configure a lifecycle rule that transitions the DNA sequencing outputs directly to S3 Glacier Deep Archive on Day 24, and a separate rule that deletes the metadata logs on Day 25 without transition.

Synthesize the individual file-type policies into a single cost-optimized strategy.

Key Concept

S3 Standard-IA has a minimum billing size of

128\text{ KB}

and a minimum storage duration of

30\text{ days}

. Moving files smaller than

128\text{ KB}

or transitioning/deleting objects before

30\text{ days}

in Standard-IA results in unnecessary costs. Direct transition from S3 Standard to S3 Glacier Deep Archive is valid and avoids intermediate IA tier penalties.

Estimated Time:3m 0s

Question

Answer

Step-by-Step Solution

Key Concept

Common Mistakes

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