Quick & simple question, but couldn't find anything in the docs:
In my emrfs-site.xml, can I set both fs.s3.enableServerSideEncryption and fs.s3.cse.enabled to true? Will that provide double encryption, or it's not possible?
No, "Amazon S3 SSE and CSE are mutually exclusive; you can choose either but not both." per http://docs.aws.amazon.com/emr/latest/ReleaseGuide/emr-cluster-configuration-object-encryption.html