How to grant set the replication attribute on RDS PostgreSQL?

On the AWS RDS documentation I see that rds_superuser can:


Grant and revoke the replication attribute onto all roles that are not
the rds_superuser role. For more information, see this section in the
PostgreSQL documentation.

source: http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_PostgreSQL.html

But, if I try, while logged in as my rds_superuser:

ALTER ROLE ROLENAME WITH REPLICATION;

I get an error stating that I cannot perform that action due to not being a superuser.

Do you guys know how to set the replication attribute to a user?

We hit this head on too, and after much frustration discovered:

CREATE ROLE some-user WITH LOGIN PASSWORD 'long-password';
grant rds_replication to user;


This seems to be working for logical replication.

UPDATE: Note that the user on the publisher needs to have SELECT access too!

StackExchange Database Administrators Q#186013, answer score: 13