Cross-account and cross region read replica for Amazon Aurora PostgreSQL

Hello.

It seems that cross-region replication is not possible with Aurora PostgreSQL.
https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/AuroraPostgreSQL.Replication.html

Aurora PostgreSQL DB clusters don't support Aurora Replicas in different AWS Regions, so you can't use Aurora Replicas for cross-Region replication.

Why not consider global databases instead?
https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/aurora-global-database.html

I can't find much information about cross-account, and I'm not sure if it's possible, but it may be possible to perform cross-account replication by setting up continuous replication using something like AWS DMS.
The AWS blog below explains Aurora MySQL rather than Aurora PostgreSQL, but I thought it could be used as a configuration.
https://aws.amazon.com/jp/blogs/database/perform-cross-account-amazon-aurora-mysql-migration-with-minimal-downtime/

Hi Deepak

Let me clarify the answer above.... Aurora MySQL has a deployment option that was built prior to Global Databases to place a read replica in another region (but not another account) and uses binlog replication to keep it in sync with the primary writer instance. This approach was never implemented by Aurora PostgreSQL because Global Database models for multi-region support is far superior. This is what the initial doc reference in the answer above is describing. I think the public docs could use some clarification because this really is trying to say that Aurora PostgreSQL's create / modify APIs and its' control plane automation do not support creating and managing native PostgreSQL replication either across regions or across accounts. However, if a customer wants to implement it on their own using native PostgreSQL replication or the pglogical extension, this is certainly possible and would support cross-region and cross-account models. The caveat is obviously that you will have to build it and manage yourself. See the documentation for this at https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/Appendix.PostgreSQL.CommonDBATasks.pglogical.html.

Aurora Global Databases automate this for you and because its implemented within the Aurora Storage layer of the architecture, replication has dramatically less impact on the performance of the primary writer instance and much lower replication lag between regions. The doc link in the above answer is a good place to start.... Currently, Global Databases do not support cross-account models but that is something we are considering in the future.

Hope this helps...