Amazon EMR
Management Guide

EMRFS Endpoint Resolution

EMRFS now resolves to the regional endpoints in which a cluster is running when it makes calls to Amazon S3. Cross-region calls between clusters and buckets not co-located in the same region may fail. This may affect scripts and other artifacts that use older non-regionalized URIs. For more information about region-specific Amazon S3 endpoints, see AWS Regions and Endpoints in the Amazon Web Services General Reference.