I have a DMS source endpoint (SQL Server) linked to a Secrets Manager secret with my DB credentials in it. I've previously created serverless tasks using this endpoint, which successfully performed initial load and CDC (and some are still actively pulling CDC). This indicates that The task, endpoint, secret and network are configured correctly, as well as any necessary IAM permissions.
However, as of yesterday, any attempt to create a new serverless migration task using the already existing endpoint/secret ends up failing with the following error:
Failed to fetch the secret from the AWS Secrets Manager. Please check if the permissions are set up correctly: https://docs.aws.amazon.com/dms/latest/userguide/security_iam_secretsmanager.html
In addition, when reviewing the "problematic" endpoint via the console and testing the connection manually - the test end up being successful.
UPDATE:
Just to be sure, I've created a replication instance and a non-serverless replication task using the same source endpoint and it works fine. This issue seems to be limited to serverless tasks.
I'm wondering if I'm doing something wrong, or is it a faulty behaviour of DMS - does anyone else experience similar issues?
Thanks Didier, just to be sure I created a replication instance and tried running the task on it - that works fine, which indicated the issue is not around networking, IAM permissions or access to SM. It seems to be limited to serverless tasks.