Object Storage Service (OSS) provides two storage redundancy types: zone-redundant storage (ZRS) and locally redundant storage (LRS). These types use data redundancy mechanisms across single, dual, or multiple zones to ensure data durability and availability.
Zone-redundant storage (ZRS)
ZRS uses a multi-zone data redundancy mechanism to store data copies across multiple zones. In regions with three or more zones, data copies are stored across at least three zones. In regions with two zones, a dual-zone mechanism is used to store data copies across both zones. This ensures that data remains accessible even if one zone becomes unavailable.
Data in zone-redundant storage is stored within a single region. If that region becomes unavailable, the data is inaccessible. If your business requires very high availability, use cross-region replication to back up your data.
Locally redundant storage (LRS)
LRS uses a data redundancy mechanism within a single availability zone (AZ), storing redundant copies of your data on multiple devices across multiple facilities in the same AZ. This ensures data durability and availability in the event of hardware failures.
Data in locally redundant storage is stored within a single zone. If that zone becomes unavailable, the data is inaccessible. If your business requires higher availability, use zone-redundant storage (ZRS).
Comparison of storage redundancy types
The following table compares the data durability and service availability of LRS and ZRS.
Storage redundancy type | Storage class | Region | Data durability | Service availability |
Zone-redundant storage | Standard | China (Hangzhou), China (Shanghai), China (Beijing), China (Zhangjiakou), China (Ulanqab), China (Shenzhen), China (Hong Kong), Japan (Tokyo), Singapore, Indonesia (Jakarta), Malaysia (Kuala Lumpur), Germany (Frankfurt) | 99.9999999999% (12 nines) | 99.995% |
US (Silicon Valley), US (Virginia), Philippines (Manila), Thailand (Bangkok), South Korea (Seoul), UAE (Dubai), UK (London) Note To enable this feature in the US (Virginia) region, contact Technical Support. | 99.99% | |||
Infrequent Access | China (Hangzhou), China (Shanghai), China (Beijing), China (Zhangjiakou), China (Ulanqab), China (Shenzhen), China (Hong Kong), Japan (Tokyo), Singapore, Indonesia (Jakarta), Malaysia (Kuala Lumpur), Germany (Frankfurt) | 99.50% | ||
Archive Storage | ||||
Locally redundant storage | Standard | All public cloud regions | 99.999999999% (11 nines) | 99.99% |
Infrequent Access | 99% | |||
Archive Storage | ||||
Cold Archive | China (Hangzhou), China (Shanghai), China (Qingdao), China (Beijing), China (Zhangjiakou), China (Hohhot), China (Ulanqab), China (Shenzhen), China (Heyuan), China (Guangzhou), China (Chengdu), China (Hong Kong), US (Silicon Valley), US (Virginia), Mexico, Japan (Tokyo), Singapore, Malaysia (Kuala Lumpur), Indonesia (Jakarta), Philippines (Manila), Germany (Frankfurt), UK (London), UAE (Dubai) | |||
Deep Cold Archive | China (Hangzhou), China (Shanghai), China (Beijing), China (Zhangjiakou), China (Ulanqab), China (Shenzhen), Singapore |
Related operations
To create a bucket with the zone-redundant storage type, see Create a zone-redundant storage bucket.
To convert the storage redundancy type of a bucket from LRS to ZRS, see Convert the storage redundancy type of a bucket.