Object Storage Service (OBS) supports cross-region replication

Cross-region replication provides a solution for disaster recovery across regions, allowing users to set up a remote backup solution.

Cross-region replication refers to the process of automatically and asynchronously replicating data from a bucket (source bucket) to another bucket (destination bucket) across regions by creating a cross-region replication rule. The source bucket and destination bucket must belong to the same account. Replication across accounts is not supported.

For a cross-region replication rule, users can configure it to match a pre-defined object prefix so that all objects with this prefix will be replicated. Alternatively, they can configure the rule to apply to the whole bucket so that all objects in the bucket will be replicated. Objects replicated to the destination bucket are precise copies of objects in the source bucket. They have the same object names, metadata, content, size, last modification time, creator, version ID, user-defined metadata, and ACLs. By default, the storage class of an object copy is the same as that of the source object. Users can also specify a different storage class for an object copy.

Figure 1 : Cross-region replication

Regulatory compliance: OBS stores data across AZs that are relatively far apart from each other. However, regulatory compliance may require further distances. Cross-region replication enables OBS to replicate data across regions for regulatory compliance.

Minimized latencies: the same OBS resources may need to be accessed from different locations. To minimize the access latency, you can use cross-region replication to create object copies in the region nearest to end users.

Data replication: cross-region replication allows you to easily migrate your data stored in OBS from one region to another.

Data backup and disaster recovery: to ensure data security and availability, you need to create explicit backups for all data written to OBS in the data center of another region, so that secure backup is available in case the source data is damaged irrevocably.

Easy maintenance: users have a computing cluster across regions to analyze the same collection of objects. You need to maintain object replicas in the two regions.

Contents Replicated

After the cross-region replication rule is enabled, objects that meet the following conditions are copied to the destination bucket:

  • Newly uploaded objects (excluding objects in the Archive storage class)
  • Updated objects. For example, the object content is updated or the ACL information of a copied object is updated.
  • Historical objects in a bucket if Synchronizing Existing Objects is enabled (excluding objects in the Archive storage class)