AZ-305 Question 140
Single answerYou are designing a solution for an e-commerce platform that stores product information in JSON (semi-structured data) and user-uploaded images (unstructured data). The platform requires at least 99.99% availability for both data types across multiple Azure regions with automatic failover in the event of a regional outage. Which recommended approach best meets these requirements?
- A
Use Azure Cosmos DB with multi-region writes for JSON data and Azure Storage with geo-redundant storage (GRS) for images.
- B
Use Azure SQL Database in a single region for JSON data and locally redundant storage (LRS) for images.
- C
Use an on-premises NoSQL database cluster for JSON data and mount Azure Files with zone-redundant storage (ZRS) for images.
- D
Use Azure Cache for Redis to store JSON data and replicate to another region, while storing images in Azure Disk Storage set to LRS.
Show answer and explanation
Correct answer: A
Explanation
A common best practice for ensuring high availability of semi-structured data (e.g., JSON) is to use Azure Cosmos DB with multi-region writes and automatic failover. For unstructured data (e.g., images, videos), Azure Storage with geo-redundant replication (GRS or RA-GRS) ensures data is stored in a secondary region for disaster recovery. This approach aligns with Microsoft documentation on designing highly available cloud data solutions (see https://docs.microsoft.com/azure/cosmos-db/high-availability and https://docs.microsoft.com/azure/storage/common/storage-redundancy).
- A. Correct.
Correct: Azure Cosmos DB with multi-region writes provides global distribution and high availability for JSON data, automatically failing over if needed. Azure Storage with geo-redundant storage (GRS) replicates unstructured data asynchronously to a secondary region, ensuring high availability for images.
- B. Incorrect.
Incorrect: Using Azure SQL Database in a single region doesn't meet the multi-region requirement for high availability. Locally redundant storage (LRS) only keeps data in one region, so there's no regional failover.
- C. Incorrect.
Incorrect: An on-premises NoSQL cluster complicates global availability, and Azure Files with zone-redundant storage (ZRS) only protects against availability zone failures within the same region, not a regional outage.
- D. Incorrect.
Incorrect: Azure Cache for Redis is designed for caching, not as a primary data store for large-scale semi-structured data like JSON. Azure Disk Storage with LRS is limited to a single region and does not provide cross-region failover.