Microsoft Certified: Azure Developer Associate (AZ-204)Develop for Azure storageMedium
An application uses Azure Blob Storage to store millions of small log files (average size 10 KB). These files are rarely accessed after the first 30 days but must be retained for compliance purposes for 5 years. The company wants to minimize storage costs while ensuring the files remain accessible if needed. Which blob access tier should be used for these log files after 30 days?
- AHot
- BArchive
- CCool
- DPremium
Show answer & explanationAnswer & explanation
Correct answer: B. Archive
The Archive tier is the most cost-effective for rarely accessed data with flexible latency requirements (hours). Given the files are rarely accessed after 30 days but need to be retained for 5 years, moving them to Archive tier significantly reduces storage costs. Hot and Cool tiers are more expensive for long-term, infrequent access. Premium is for high-performance, frequently accessed data.
Why the other options are wrong
- A. Hot tier is for frequently accessed data and would be too expensive for rarely accessed log files.
- C. Cool tier is for infrequently accessed data (30 days minimum retention for cost optimization) but still has higher storage costs than Archive and faster access than Archive.
- D. Premium tier is for high-performance, highly transactional workloads and is the most expensive, completely unsuitable for rarely accessed log files.
Azure Blob Storage Archive Tier
The Azure Blob Storage Archive tier is designed for rarely accessed data with flexible latency requirements (on the order of hours). It offers the lowest storage costs but the highest data retrieval costs and latency compared to the Hot and Cool tiers.
- Lowest storage cost.
- Highest data retrieval cost and latency (hours).
- Ideal for long-term backup, archival, and compliance data.
- Data must be rehydrated to Hot or Cool tier before access.
Memory trick: Hot for Hitting, Cool for Casual, Archive for Ancients.