AZ-305 Question 88
Single answerYour organization collects large volumes of time-series data generated by IoT devices. The data is accessed frequently for the first 90 days to generate operational insights. After 90 days, the data is needed only occasionally for historical analysis and regulatory compliance, but it must remain available for up to seven years. The team wants to minimize storage costs while still being able to retrieve the data within a reasonable time frame. Which Azure storage approach best meets these requirements?
- A
Store all IoT device data in the Azure Blob Hot tier indefinitely.
- B
Use Azure Blob Lifecycle Management to move data from the Hot tier to Cool tier after 90 days.
- C
Place all new data immediately into the Archive tier to minimize costs from day one.
- D
Store data in Azure Files with a Premium performance tier to ensure quick retrieval.
Show answer and explanation
Correct answer: B
Explanation
Azure Blob Storage offers multiple access tiers (Hot, Cool, and Archive), and Lifecycle Management policies allow you to automatically transition data between tiers over time. Storing time-series data in the Hot tier initially ensures high performance for frequent access, then moving it to the Cool tier provides cost savings when the data becomes infrequently accessed. This approach aligns with Azure best practices for balancing performance and cost. For more details, refer to Microsoft Docs on managing access tiers (https://docs.microsoft.com/azure/storage/blobs/storage-blob-storage-tiers).
- A. Incorrect.
Option 1 is incorrect because keeping all data in the Hot tier indefinitely would result in higher costs for data that is only occasionally accessed after 90 days.
- B. Correct.
Option 2 is correct. Using Azure Blob Storage with Lifecycle Management policies to move data from the Hot tier to the Cool tier after 90 days balances cost and retrieval needs. The Hot tier covers frequent access for the first 90 days, and then the data transitions to the Cool tier for lower cost when infrequently accessed.
- C. Incorrect.
Option 3 is incorrect because putting data directly into the Archive tier would make frequent access and analysis for the first 90 days difficult. Archive tier also requires rehydration before retrieval, which is not suitable for data that is actively analyzed early on.
- D. Incorrect.
Option 4 is incorrect because using Azure Files with a Premium tier is more expensive and not necessary unless you need file-sharing features with very high performance. Archiving and lifecycle management are not as seamless in Azure Files for long-term retention as in Blob Storage.