replicate
Specifies that this resource is a Replicate database, and to use this value as the source database. This correlates to the identifier of another Amazon RDS Database to replicate (if replicating within a single region) or ARN of the Amazon RDS Database to replicate (if replicating cross-region). Note that if you are creating a cross-region replica of an encrypted database you will also need to specify a kms_key_id. See instance-replication and [Working with
PostgreSQL and MySQL Read Replicas](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_ReadRepl.html) for more information on using Replication.