An autonomous vehicle research company stores two telemetry datasets in a single Amazon S3… — AWS Certified Solutions Architect - Associate

An autonomous vehicle research company stores two telemetry datasets in a single Amazon S3 bucket:
- LiDAR Point Cloud Blocks: Average file size of $180\text{ MB}$ . These files are analyzed intensively for $14\text{ days}$ after upload. They must be preserved for compliance audits and can be deleted exactly $45\text{ days}$ after upload.
- CAN Bus Sensor Logs: Average file size of $3\text{ KB}$ . These files are queried sporadically for the first $10\text{ days}$ and must be retained indefinitely for long-term machine learning training.

Which combination of actions will result in the most cost-effective storage architecture that meets the retention requirements? (Select two.)

Configure an S3 Lifecycle rule for the LiDAR Point Cloud Blocks to transition objects to S3 Standard-Infrequent Access (S3 Standard-IA) after $14\text{ days}$ , and expire them after $45\text{ days}$ .Answer
B
Configure an S3 Lifecycle rule for the LiDAR Point Cloud Blocks to transition objects to S3 Glacier Instant Retrieval after $14\text{ days}$ , and expire them after $45\text{ days}$ .
Configure an S3 Lifecycle rule for the CAN Bus Sensor Logs that filters on object size (using ObjectSizeGreaterThan set to $128\text{ KB}$ ) to transition logs to S3 Standard-IA after $10\text{ days}$ , leaving smaller logs in S3 Standard.Answer
D
Configure an S3 Lifecycle rule for the CAN Bus Sensor Logs to transition all logs to S3 Standard-IA after $10\text{ days}$ to lower active storage costs.
E
Configure an S3 Lifecycle rule for the CAN Bus Sensor Logs to transition all logs to S3 Intelligent-Tiering after $10\text{ days}$ to automatically tier them to Archive Instant Access after $90\text{ days}$ .

Answer

Configure an S3 Lifecycle rule to transition the large LiDAR files to S3 Standard-IA after

14\text{ days}

and expire them at

45\text{ days}

, and configure a separate S3 Lifecycle rule for the CAN Bus logs filtering by object size (greater than

128\text{ KB}

) before transitioning them to S3 Standard-IA after

10\text{ days}

Transitioning the LiDAR files to S3 Standard-IA after

14\text{ days}

and expiring them at day

45

results in a

31\text{-day}

storage period in the IA tier. Since S3 Standard-IA has a minimum storage duration of

30\text{ days}

, no early deletion penalty is applied. The large size of the LiDAR files (

180\text{ MB}

) also makes them ideal for S3 Standard-IA. For the small CAN Bus logs (

3\text{ KB}

), S3 Standard-IA's minimum billing size of

128\text{ KB}

makes direct transitions cost-ineffective. Filtering transitions to only affect objects larger than

128\text{ KB}

avoids this storage charge penalty.

Step-by-Step Solution

Calculate the active storage duration in the transition tier for the LiDAR dataset.

The files spend

31\text{ days}

in the target Infrequent Access tier (

45\text{ days}

total retention minus

14\text{ days}

in S3 Standard).

This determines if the transition triggers early deletion charges in the target storage tier.

Verify target tier minimum duration constraints against the calculated storage duration.

S3 Standard-IA has a

30\text{ day}

minimum storage duration (

31 \geq 30

is valid with no penalty), whereas S3 Glacier Instant Retrieval has a

90\text{ day}

minimum (

31 < 90

incurs a pro-rated

59\text{ day}

penalty).

This step identifies the most cost-effective storage tier that aligns with the deletion window.

Evaluate the average file size of the CAN Bus Sensor Logs (

3\text{ KB}

) against minimum billing sizes.

S3 Standard-IA charges a minimum of

128\text{ KB}

per object, making a

3\text{ KB}

file transition highly cost-ineffective due to the

42.6\times

size overhead billing penalty.

This analysis prevents unintended cost inflation when tiering small files.

Select the S3 Lifecycle rule filters that selectively transition objects based on size criteria.

Apply an `ObjectSizeGreaterThan` filter set to

128\text{ KB}

to exclude small telemetry logs from transitioning, keeping them in S3 Standard.

This ensures only cost-effective objects are transitioned to the standard-IA tier.

Key Concept

Applying storage tiering lifecycle policies while accounting for minimum storage durations, early deletion penalties, and minimum object size billing constraints in Amazon S3.

Question

Answer

Step-by-Step Solution

Key Concept

Common Mistakes

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