What are good options for a multi master replication enabled, scalable database. We are talking about 15-16 TB of data. We are thinking DynamoDB. Are there any more databases which we should look up. Any advice on DynamoDB usage as well as new ideas about the required database type is welcome.
Currently, DynamoDB supports cross-region replication with the cross-region replication library on Github. It should be somewhat straightforward to divide up the partition and sort key space by region and then run the library in each region. You would have to modify the library to ignore stream records for items that are not mastered in the region (each region should only propagate changes for items mastered in that region). In this setup, each master-replica table in each region will have a stream enabled and each region should have an EC2 instance processing that table's DynamoDB stream.