Multi-AZ storage
Updated at:2025-11-03
Overview
With multi-AZ storage enabled, BOS distributes user data across multiple availability zones within the same region.
Multi-AZ storage offers robust disaster recovery capabilities. Even if a specific availability zone becomes unavailable due to physical issues, BOS ensures uninterrupted data access, maintaining business continuity.
Metric comparison
The following is a comparison of various metrics for standard storage objects when multi-AZ storage is enabled versus disabled:
| Comparison indicators | Standard storage-multi-AZ | Standard storage | Infrequent access storage-multi-AZ | Infrequent access storage |
|---|---|---|---|---|
| Availability | 99.995% | 99.99% | 99.995% | 99.95% |
| Minimum storage duration | None | None | 30 days | 30 days |
| Data restoration fees | None | None | Pay-as-you-go (GB) | Pay-as-you-go (GB) |
| Data access feature | Provides real-time access with millisecond-level latency. | Provides real-time access with millisecond-level latency. | Provides real-time access with millisecond-level latency. | Provides real-time access with millisecond-level latency. |
| Applicable scenarios | Ideal for mobile apps, video streaming on websites, data analysis, and other scenarios that demand extremely high reliability. | Suitable for mobile apps, video websites, data analysis, etc. | Fits scenarios like network disk storage, monitoring data, media asset backups, and other use cases requiring extremely high reliability. | Useful for network disk storage, monitoring data, media asset backups, and similar scenarios. |
| Scenario characteristics | Best suited for use cases with frequent data reads. | Best suited for use cases with frequent data reads. | Designed for scenarios where the average monthly access frequency is less than once. | Designed for scenarios where the average monthly access frequency is less than once. |
Description:
- The data reliability of standard storage, standard storage - multi-AZ, infrequent access storage, and infrequent access storage - multi-AZ all achieves 99.9999999999% (12 nines).
Operation types
Users can enable multi-AZ storage when creating a bucket via the console. For detailed steps, please refer to:
- [Configuring Multi-AZ Storage via the Console](BOS/Console Operation Guide/Managing Bucket/Create bucket.md).
Instructions for use
- BOS only allows the multi-AZ storage class to be selected at the time of bucket creation. Once a bucket is created, its multi-AZ storage status cannot be modified. Plan accordingly based on your business requirements.
- At present, BOS Multi-AZ storage supports two types: standard storage - multi-AZ and infrequent access storage - multi-AZ.
- BOS multi-AZ storage is currently available in the North China - Beijing, East China - Suzhou, and South China - Guangzhou regions. You can obtain access permissions by submitting a ticket.
- Currently, it is not possible to convert existing (legacy) buckets to the multi-AZ storage class.
