Why are imported data sets not appearing in AWS S3 storage, and Batch Analysis jobs stuck in Submitting state?

Why are imported data sets not appearing in AWS S3 storage, and Batch Analysis jobs stuck in Submitting state?

Problem:

Imported data not copied to S3 and Batch Analysis jobs stuck in submitting state

Errors similar to those shown below are seen in the /var/log/columbus/web/long-tasks.log file.

EndpointConnectionError: Could not connect to the endpoint URL: "https://s3.eu-west-1a.amazonaws.com/"
EndpointConnectionError: Could not connect to the endpoint URL: "https://elasticmapreduce.eu-west-1a.amazonaws.com/"

Cause:

The AWS endpoint is invalid because "eu-west-1a" is not a valid region ("eu-west-1" is correct).

Solution:

Ensure that the AWS "region_name" parameter in the cluster config file found in /etc/columbus points to a valid AWS region.