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A financial services company needs to store transaction records that must be immutable and retained for seven years for regulatory compliance. These records are written once and rarely read, primarily for auditing purposes. The company wants to minimize storage costs while meeting compliance requirements. Which Azure storage solution and configuration should be used?
- AAzure Blob Storage with Hot tier and a seven-year retention policy
- BAzure SQL Database with transparent data encryption
- CAzure Data Lake Storage Gen2 with Geo-redundant storage
- DAzure Blob Storage with Archive tier and an immutability policy
Show answer & explanationAnswer & explanation
Correct answer: D. Azure Blob Storage with Archive tier and an immutability policy
Azure Blob Storage Archive tier is the most cost-effective solution for rarely accessed, long-term data. Combining it with an immutability policy ensures that the data cannot be altered or deleted for the required seven-year retention period, satisfying regulatory compliance.
Why the other options are wrong
- A. Hot tier is expensive for rarely accessed data. A retention policy alone doesn't guarantee immutability against deletion or modification by privileged users.
- B. Azure SQL Database is a relational database for transactional data, not a cost-effective solution for large volumes of immutable, rarely accessed audit logs. TDE encrypts data at rest but doesn't provide immutability.
- C. Azure Data Lake Storage Gen2 is for analytics workloads, not primarily for immutable, low-cost archival storage. Geo-redundancy addresses durability, not immutability or cost-effectiveness for archives.
Azure Blob Storage Archive Tier with Immutability
The Azure Blob Storage Archive tier offers the lowest storage costs for infrequently accessed data with flexible latency requirements. An immutability policy ensures that data stored in a blob container cannot be modified or deleted for a specified period, crucial for regulatory compliance.
- Archive tier: Lowest cost, highest latency for access (hours)
- Immutability policy: Prevents deletion or modification for a defined retention period
- Ideal for compliance, auditing, and long-term backups
- Data is 'write once, read many' (WORM) compliant
Memory trick: Archive blobs with immutability, records frozen in time.