AWS DMS "Load complete, replication ongoing" not working MongoDB to DocDB

Question

I am trying to make a PoC for MongoDB to DocDB migration with DMS. I've set up a MongoDB instance with some dummy data and an empty DocDB. Source and Target endpoints are also set in DMS and both of them are connecting successfully to my databases.

When I create a migration task in DMS everything seems to be working fine. All existing data is successfully replicated from the MongoDB instance to DocDB and the migration task state is at " Load complete, replication ongoing ". At this point I tried creating new entries in existing collections as well as creating new empty collections in MongoDB but nothing happens in DocDB. If I understand correctly the replication should be real time and anything I create should be replicated instantly? Also there are no indication of errors or warnings whatsoever... I don't suppose its a connectivity issue to the databases since the initial data is being replicated. Also the users I am using for the migration have admin privileges in both databases.

Does anyone have any suggestions?

Answer 1

@PPetkov - could you check the following? 1. Check if right privileges were assigned to the user in the MongoDB endpoint according to https://docs.aws.amazon.com/dms/latest/userguide/CHAP_Source.MongoDB.html . 2. Check if replicate set to capture changes was appropriately configured in the MongoDB instance. 3. Once done, try to search for "]E:" or "]W:" in the CloudWatch logs to understand if there are any noticeable failures/warnings.