AZ-305 Question 93
Single answerFabrikam is storing 500 TB of business-critical data in Azure Storage. They must ensure high durability and have immediate read access if their primary Azure region becomes unavailable. Which redundancy option best meets these requirements?
- A
Locally redundant storage (LRS)
- B
Zone-redundant storage (ZRS)
- C
Geo-redundant storage (GRS)
- D
Read-access geo-zone-redundant storage (RA-GZRS)
Show answer and explanation
Correct answer: D
Explanation
For mission-critical data, combining zone redundancy and geo-redundancy is crucial. RA-GZRS (Read-Access Geo-Zone-Redundant Storage) stores data across availability zones in the primary region and replicates it to a geographically distant secondary region. It also enables read access to the replicated data in the event of a primary region outage, meeting the strictest requirements for durability and high availability. For more details, see Azure Storage replication options documentation on Microsoft Learn (https://learn.microsoft.com/azure/storage/common/storage-redundancy).
- A. Incorrect.
LRS only keeps multiple copies of your data within one Azure data center, providing no regional failover. This doesn't meet the requirement for immediate read access in a regional outage.
- B. Incorrect.
ZRS replicates data across different availability zones within the same Azure region. Although more resilient than LRS, it still doesn't provide a cross-region failover for disaster recovery.
- C. Incorrect.
GRS replicates data to a secondary region but doesn't offer immediate read access to the secondary copy. Data can only be accessed from the secondary if Microsoft initiates a failover.
- D. Correct.
RA-GZRS combines zone redundancy in the primary region with a secondary region replication and allows read access to the secondary copy. This meets both the durability and immediate read access requirements.