Examkin

Soru

Zorluk: OrtaCost-Optimized Storage Tiering and Lifecycle Management

A financial analytics firm generates daily transaction summaries that are stored in an Amazon S3 bucket. The summaries are accessed frequently by downstream applications for the first 30 days30 \text{ days} after creation. After 30 days30 \text{ days}, access to the summaries drops to almost zero, but they must be retained for compliance purposes for a total of 45 days45 \text{ days} from creation. During the compliance retention period, the summaries must remain queryable within milliseconds. Which of the following lifecycle configurations represents the most cost-effective storage strategy for these summaries?

  1. Keep the transaction summaries in S3 Standard for the entire 45 days45 \text{ days}, then use a lifecycle rule to expire the objects.Cevap
  2. B
    Transition the transaction summaries to S3 Standard-Infrequent Access (S3 Standard-IA) after 30 days30 \text{ days}, and expire the objects after 45 days45 \text{ days}.
  3. C
    Transition the transaction summaries to S3 Glacier Flexible Retrieval after 30 days30 \text{ days}, and expire the objects after 45 days45 \text{ days}.
  4. D
    Transition the transaction summaries to S3 Glacier Instant Retrieval after 30 days30 \text{ days}, and expire the objects after 45 days45 \text{ days}.

Cevap

Keep the transaction summaries in S3 Standard for the entire 45 days, then use a lifecycle rule to expire the objects.
Keeping the files in S3 Standard for the entire duration is the most cost-effective solution because the storage duration in the lower tier (15 days) is shorter than the minimum billing threshold of S3 Standard-IA (30 days) and S3 Glacier Instant Retrieval (90 days). The cost of paying the minimum storage duration penalty makes transitioning the objects more expensive than maintaining them in the standard tier.

Adım Adım Çözüm

1
Calculate the storage cost of keeping the summaries in S3 Standard for the entire 45 days45 \text{ days}.
The cost is approximately $0.0345\$0.0345 per GB.
S3 Standard charges $0.023\$0.023 per GB-month. For 45 days45 \text{ days}, the prorated storage cost is 45 days×($0.023/30 days)=$0.034545 \text{ days} \times (\$0.023 / 30 \text{ days}) = \$0.0345 per GB.
2
Calculate the storage cost of transitioning the summaries to S3 Standard-IA at day 30 and expiring them at day 45.
The cost is approximately $0.0355\$0.0355 per GB plus transition request fees.
S3 Standard-IA has a minimum storage duration of 30 days30 \text{ days}. Transitioning at day 30 and deleting at day 45 means the objects spend only 15 days15 \text{ days} in S3 Standard-IA but are billed for 30 days30 \text{ days}. The cost is 30 days in S3 Standard (30×$0.023/30=$0.02330 \times \$0.023 / 30 = \$0.023) plus 30 days of S3 Standard-IA (30×$0.0125/30=$0.012530 \times \$0.0125 / 30 = \$0.0125), totaling $0.0355\$0.0355 per GB.
3
Evaluate S3 Glacier options against retrieval time constraints and minimum storage duration rules.
S3 Glacier Flexible Retrieval fails the millisecond query requirement. S3 Glacier Instant Retrieval meets retrieval times but incurs a 90 day90 \text{ day} minimum storage charge, leading to a substantial early deletion penalty.
Glacier Flexible Retrieval requires minutes or hours for retrieval, which does not meet the millisecond requirement. Glacier Instant Retrieval has a minimum storage duration of 90 days90 \text{ days}, so deleting at day 45 forces a 75 day75 \text{ day} early deletion charge (90 days×$0.004/30=$0.012090 \text{ days} \times \$0.004 / 30 = \$0.0120 for storage, bringing total cost to $0.0350\$0.0350 per GB plus high transition request charges).

Anahtar Kavram

Minimizing storage costs by understanding minimum storage duration charges and retrieval latency constraints across S3 storage tiers.
Bu soruyu puanla

Konular

Cost-Optimized Storage Tiering and Lifecycle Management