A data lake holds 3 PB in S3 Standard. Access patterns: hot for 90 days, occasional for a year, then rare but must stay retrievable for compliance. What's the most cost-effective design?
A.Keep everything in S3 Standard and review quarterly
Standard forever overpays massively at PB scale.
B.Lifecycle rules: Standard → Intelligent-Tiering or Standard-IA at 90 days → Glacier Flexible at 1 year
Correct. Age-based transitions implement the optimal tiering.
C.Move everything to Glacier Deep Archive now
Deep Archive's hours-long retrieval breaks year-1 occasional access.
D.Migrate to EBS volumes
EBS is block storage — wrong fit and more expensive for object data.
Why this answer
Lifecycle transitions match storage class to access pattern over time — hot in Standard, cooling in IA/Intelligent-Tiering, archive in Glacier. It automates the optimal cost curve; Deep Archive too early breaks the 'occasional' access year.
Correct answer: B · Last reviewed 2026-10-26
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