An organization is deploying critical database backups to Azure storage. The organization needs to ensure the highest resilience against regional disasters while managing operational costs. The deployment must meet the following requirements: - Data must be replicated to a secondary physical region located hundreds of miles away from the primary region. - Data in the primary region must be protected against local hardware failures. - The secondary replica is only required during a regional failover, so continuous read access to the secondary region is not needed. Which storage redundancy option should the organization configure?

Geo-redundant storage (GRS): ### What Geo-Redundant Storage (GRS) Is **Geo-redundant storage (GRS)** is an Azure data redundancy option designed to deliver regional disaster recovery. It synchronizes data within the primary region and then asynchronously replicates it to a paired secondary region located hundreds of miles away. ### How It Meets the Requirements - **Cross-region disaster recovery**: GRS copies data asynchronously to a secondary region, protecting workloads against major regional outages, natural disasters, or catastrophic events. - **Primary region protection**: In the primary region, GRS maintains three synchronous copies using **Locally Redundant Storage (LRS)** principles, protecting against local disk and node failures. - **Cost efficiency**: Because GRS does not enable active read endpoints on the secondary region, it costs less than **Read-Access Geo-Redundant Storage (RA-GRS)** while fully meeting backup and disaster recovery needs. ### Key Advantages and Capabilities - Provides **six total replicas** (three in the primary region and three in the secondary paired region). - Delivers at least **16 nines (99.99999999999999%) of data durability** over a given year. - Supports automated or customer-managed **failover** to the secondary region if the primary region becomes permanently unavailable. ### Why This Is Optimal GRS satisfies all requirements by providing cross-region replication for disaster resilience without incurring the extra costs associated with continuous read access to the secondary region.