DynamoDB Cross-Region Replication

DynamoDB cross-region replication allows you to maintain identical copies (called replicas) of a DynamoDB table (called master table) in one or more AWS regions.

After you enable cross-region replication for a table, identical copies of the table are created in other AWS regions. Writes to the table will be automatically propagated to all replicas.

DynamoDB Cross-region Replication - Use Cases

You can use cross-region replication for the following scenarios.

1. Efficient disaster recovery:

   1. Can switch over to using tables from another region in case a data center failure occurs.

2. Faster reads:

   1. Can deliver data faster by reading a DynamoDB table from the closest AWS data center.

3. Easier traffic management:

   1. Can use replicas to distribute the read workload across tables.

4. Easy regional migration:

   1. By creating a read replica in a new region and then promoting the replica to be a master.

5. Live data migration:

   1. To move a DynamoDB table from one region to another, you can create a replica of the table from the source region in the destination region. When the tables are in sync, you can switch your application to write to the destination region.

DynamoDB Cross-region - Pricing

Pricing: While there is no additional charge for the cross-region replication library, you pay the usual prices for the following resources used by the process. You will be billed for:

1. Provisioned throughput (Writes and Reads) and storage for the replica tables.

2. Data Transfer across regions.

3. Reading data from DynamoDB Streams to keep the tables in sync.

4. The EC2 instances provisioned to host the replication process. The cost of the instances will depend on the instance type you choose and the region hosting the instances.