Amazon EMR
Management Guide

EMR File System (EMRFS) (Optional)

The EMR File System (EMRFS) and the Hadoop Distributed File System (HDFS) are both installed as components in the release. EMRFS is an implementation of HDFS which allows clusters to store data on Amazon S3. You can enable Amazon S3 server-side and client-side encryption as well as consistent view for EMRFS using the AWS Management Console, AWS CLI, or you can use a bootstrap action (with CLI or SDK) to configure additional settings for EMRFS.

Enabling Amazon S3 server-side encryption allows you to encrypt objects written to Amazon S3 by EMRFS. EMRFS support for Amazon S3 client-side encryption allows your cluster to work with S3 objects that were previously encrypted using an Amazon S3 encryption client. Consistent view provides consistency checking for list and read-after-write (for new put requests) for objects in Amazon S3. Enabling consistent view requires you to store EMRFS metadata in Amazon DynamoDB. If the metadata is not present, it is created for you.