OSS uses the multi-zone mechanism to distribute user data across three zones within the same region. Even if one zone becomes unavailable, the data can still remain accessible. The zone-redundant storage (ZRS) feature can provide data durability (designed for) of 99.9999999999% (twelve 9's) and service availability of 99.995%.

ZRS offers data center-level disaster recovery capabilities. When a data center is unavailable due to network disconnections, power outages, or other disaster events, OSS can continue to provide highly consistent services. This way, services are not interrupted and data is not lost during failovers. This meets the strict requirements of key business systems that the recovery time objective (RTO) and the recovery point objective (RPO) must be zero.

Implementation methods

You can configure ZRS for a bucket only when you create the bucket. For an existing bucket, you can use migration tools such as ossimport and Data Transport to migrate data from the existing bucket to another bucket that has ZRS enabled.

You can use the methods described in the following table to enable ZRS when you create a bucket.
Implementation method Description
Console A user-friendly and intuitive web application
ossbrowser An easy-to-operate graphical tool
ossutil A high-performance command-line tool
Java SDK SDK demos in a variety of languages
Python SDK
Node.js SDK

Usage notes

  • Supported regions

    ZRS is supported in the following regions: China (Shenzhen), China (Beijing), China (Hangzhou), China (Shanghai), China (Hong Kong), and Singapore (Singapore).

  • Billing information

    ZRS incurs more costs than locally redundant storage (LRS). For more information, see OSS pricing page.

Supported storage classes

ZRS supports the Standard and Infrequent Access (IA) storage classes. The following table compares the two storage classes from different dimensions.

Index Standard IA
Data durability (designed for) 99.9999999999% (twelve 9's) 99.9999999999% (twelve 9's)
Service availability 99.995% 99.50%
Minimum billable size of objects None 64 KB
Minimum storage period None 30 days
Data retrieval fees None Billed based on the size of retrieved data. Unit: GB.
Data access Real-time access with low latency (within milliseconds) Real-time access with low latency (within milliseconds)
IMG Supported Supported