1The Hidden Costs of IA
A common mistake is moving active data to Standard-IA just because the storage price per GB is lower. However, Standard-IA charges a retrieval fee every time an object is read. If you put an active website logo in Standard-IA, your bill will explode due to retrieval fees. Furthermore, IA classes have a minimum storage duration of 30 days; deleting an object after 5 days still incurs a 30-day charge.
2The Magic of Intelligent-Tiering
Predicting access patterns across millions of objects is practically impossible for humans. S3 Intelligent-Tiering solves this by monitoring access. If an object isn't touched for 30 days, it moves to the Infrequent tier. If untouched for 90 days, it moves to Archive. If it's suddenly read, it instantly moves back to the Frequent tier with no retrieval fees. For unknown workloads, Intelligent-Tiering is the best practice.
3Step-by-Step Breakdown
Why Storage Classes?. Not all data is accessed equally. Storing terabytes of old backup archives at the same price as active website images is a waste of money.
S3 Standard. Standard is the default. It offers low latency and high throughput for frequently accessed data (like mobile app assets). It has the highest storage cost but zero retrieval fees.
Standard-Infrequent Access (IA). Standard-IA is for data accessed less than once a month, but needed rapidly when called upon. Storage is cheaper, but you pay a per-GB retrieval fee.
S3 One Zone-IA. Unlike other classes that store data across 3 AZs, One Zone-IA stores data in a single AZ. It is 20% cheaper than Standard-IA, but data is lost if the AZ is destroyed.
S3 Intelligent-Tiering. Intelligent-Tiering automatically moves objects between frequent, infrequent, and archive access tiers based on actual access patterns, for a small monitoring fee.
Storage Check. Which S3 storage class stores data in only one Availability Zone (AZ)?
- →S3 Standard
- →S3 One Zone-IA
- →S3 Glacier Flexible Archive
S3 Glacier Instant Archive. Glacier Instant Archive is for rarely accessed data (once a quarter) that still requires millisecond retrieval. Storage is very cheap, but retrieval fees are higher.
S3 Glacier Flexible Archive. Glacier Flexible Archive is for deep archives. Storage is extremely cheap, but retrievals take between 1 minute and 12 hours depending on the retrieval option you choose.
S3 Glacier Deep Archive. Deep Archive is the absolute cheapest storage in AWS. It is designed for regulatory archiving (like 7-year financial records). Retrievals take 12 to 48 hours.
Lifecycle Policies. You can create rules to automatically transition objects between classes over time (e.g., Standard -> IA after 30 days -> Glacier after 90 days).
