Simple Log Service provides two data redundancy types: locally redundant storage (LRS) and zone-redundant storage (ZRS). These types ensure data durability and availability by providing data redundancy across one or more zones. Simple Log Service is upgrading its storage redundancy features. As a result, feature availability varies by region.
Region details
China (Hong Kong) region
The China (Hong Kong) region now fully supports ZRS. LRS is no longer supported in this region.
(1) You can create new projects only with ZRS. Creating projects with LRS is not supported.
(2) For existing projects, the underlying storage has been migrated to ZRS. On April 7, 2025, the dataRedundancyType property (data redundancy type) for these projects will be updated to ZRS.
Other regions
Upgrades are also in progress for other regions that have zone-redundant environments. In these regions, historical data is migrated to ZRS in the background.
If you urgently need ZRS resources, you can submit a ticket to request the option to select ZRS for new projects.
Currently, ZRS is supported in the China (Hangzhou), China (Shanghai), China (Beijing), China (Zhangjiakou), China (Ulanqab), China (Shenzhen), and Singapore regions. It is not yet supported in other regions.
Locally redundant storage (LRS)
LRS uses a data redundancy mechanism within a single availability zone (AZ). With LRS, your data is stored on multiple devices in different facilities within the same AZ. This design ensures data durability and availability in the event of hardware failure.
Data in LRS is redundant only within a single availability zone. If that availability zone becomes unavailable, the data will be inaccessible.
Zone-redundant storage (ZRS)
ZRS uses a data redundancy mechanism across multiple availability zones (AZs). With ZRS, your data is stored redundantly across multiple AZs in the same region. If an AZ becomes unavailable, ZRS ensures that your data remains accessible.
If a data center becomes unavailable due to a network outage, power failure, or disaster, Simple Log Service continues to provide strongly consistent service. The failover process is transparent to users and results in no data loss. This design provides minute-level recovery and a recovery point objective (RPO) of 0, which meets the requirements of critical business systems.
Comparison of storage redundancy types
The following table compares the service availability and price of LRS and ZRS.
Storage redundancy type | Service availability | Price |
Locally redundant storage | 99.9% |
|
Zone-redundant storage | 99.95% |
|