We try to replicate from AWS RDS pg11 (pglogical 2.2.1) to pg12. AWS RDS pg12 has only pglogical 2.3.0, which is not compatible to 2.2.1, and there is no way to downgrade (tried already). The replication starts and creates schemas in target, but stops then due to some errors (no need to cover it here). As a workaround we want to replicate to EC2 instance with pg12 and pglogical 2.3.1 (compatible with 2.2.1 and should work well).
Both users are setup in both databases the same way, the nodes are OK. The replication fails with
ERROR: only rds_superusers can query or manipulate replication origins.
And no idea how to debug this issue.
As already mentioned by gsteiner: the user was not explicitly granted rds_superuser role. Even though I was using a role which was initially assigned by the AWS engine, looks like it "dropped out" of rds_superuser some time ago and I had to reassign. While checking for roles, you don't see that you belong to rds_superuser(or not). So if something like this happens one might grant rds_superuser (again) to be sure that this one is resolved. Best way to ensure that this works how intended is to create a new role right away in role rds_superuser.