Redundancy and Durability¶
Azure Storage always stores multiple copies of your data so that it is protected from planned and unplanned events.
| Option | Copies | Scope | Durability | Availability | Failover |
|---|---|---|---|---|---|
| LRS | 3 | Single DC | 11 nines | 99.9% | No |
| ZRS | 3 | Across Zones | 12 nines | 99.9% | No |
| GRS | 6 | Across Regions | 16 nines | 99.9% | Customer-managed |
| GZRS | 6 | Zone + Region | 16 nines | 99.9% | Customer-managed |
| RA-GRS | 6 | Across Regions | 16 nines | 99.99% (read) | Read from secondary |
| RA-GZRS | 6 | Zone + Region | 16 nines | 99.99% (read) | Read from secondary |
mermaid graph TD Data[Your Data] --> LRS[LRS: Single Data Center] Data --> ZRS[ZRS: Three Availability Zones] Data --> GRS[GRS: LRS in Primary + LRS in Secondary] Data --> GZRS[GZRS: ZRS in Primary + LRS in Secondary] GRS --> RP[Region Pair] GZRS --> RP
Warning
Replication is not a backup. It protects against hardware or datacenter failure, but it does not protect against accidental deletion or data corruption.
Azure Files exception
Azure Files does not support RA-GRS or RA-GZRS. For eligible HDD file shares, geo-redundancy is limited to GRS or GZRS; a storage account configured with RA-GRS or RA-GZRS still bills Azure Files as GRS or GZRS. Read access to the secondary region for Azure Files requires a failover, not RA-* read behavior.
Key Concepts¶
- Durability: The likelihood that data remains accessible and uncorrupted over time.
- Availability: The percentage of time that a system is operational and accessible.
- Region Pair: Each Azure region is paired with another within the same geography.