Tablestore supports the zone-redundant storage (ZRS) redundancy type to allow you to store data in multiple data centers. This ensures high data availability and provides disaster recovery capabilities. You can create an instance in a region that supports ZRS to store data. This allows Tablestore to maintain highly consistent data even if one data center is unavailable due to a network interruption, power failure, or disaster.
Redundancy types
Tablestore provides the locally redundant storage (LRS) and ZRS redundancy types. If your application requires higher availability, we recommend that you create an instance in a region that supports ZRS to store data.
If you create an instance in a region that supports ZRS, the redundancy type of the instance is ZRS. You do not need to specify the redundancy type, and you cannot change the redundancy type.
LRS
When the LRS redundancy type is used, data is stored on multiple devices in the same zone. The LRS redundancy type ensures data durability and availability when one or more devices in the zone become invalid.
LRS data is stored in only one zone. When the zone becomes unavailable or all devices in the zone become invalid at the same time, you cannot access data in the zone.
ZRS
When the ZRS redundancy type is used, data is stored in multiple zones in the same region. The ZRS redundancy type ensures that data can be accessed when one zone becomes unavailable.
ZRS provides disaster recovery at the data center level. If a zone in the region becomes unavailable, Tablestore continues to maintain highly consistent data. The entire failover process is user-imperceptible, and can be performed without business interruption or data loss. This helps meet the requirements of key business systems for a recovery point objective (RPO) of 0 and a recovery time objective (RTO) of 0.
Differences between LRS and ZRS
LRS and ZRS differ in terms of data durability, service availability, and supported regions. The following table describes the differences between LRS and ZRS.
Item | LRS | ZRS |
Data durability | 99.999999999% (11 nines) | 99.9999999999% (12 nines) |
Service availability | 99.9% | 99.99% |
Supported regions | China (Qingdao), China (Hohhot), China (Guangzhou), China (Chengdu), Malaysia (Kuala Lumpur), Philippines (Manila), Thailand (Bangkok), UK (London), US (Silicon Valley), US (Virginia), UAE (Dubai), and SAU (Riyadh - Partner Region) | China (Hangzhou), China (Shanghai), China (Beijing), China (Zhangjiakou), China (Ulanqab), China (Shenzhen), China (Hong Kong), Japan (Tokyo), Singapore, Indonesia (Jakarta), and Germany (Frankfurt) |
Usage notes
An instance can have only one redundancy type. The redundancy type that is displayed in the Tablestore console prevails.
The redundancy type of a search index is independent of the redundancy type of the instance to which the search index belongs. The redundancy type of a search index in a region that supports ZRS is ZRS.
Billing
The ZRS redundancy type of an instance does not affect the existing billing rules of the instance.
Related operations
To prevent operations such as accidental deletion or malicious tampering from affecting the availability of important data, you can use the data backup feature to back up the table data in an instance. For more information, see Data backup.